Sample records for hallucis longus tendon

  1. Anatomic relationship of the proximal nail matrix to the extensor hallucis longus tendon insertion.

    PubMed

    Palomo López, P; Becerro de Bengoa Vallejo, R; López López, D; Prados Frutos, J C; Alfonso Murillo González, J; Losa Iglesias, M E

    2015-10-01

    The purpose of this study was to delineate the relationship of the terminal extensor hallucis longus tendon insertion to the proximal limit of the nail matrix of the great toe. Fifty fresh-frozen human cadaver great toes with no evidence of trauma (average age, 62.5 years; 29 males and 21 females) were used for this study. Under 25X magnification, the proximal limit of the nail matrix and the terminal bony insertion of the extensor hallucis longus tendons were identified. The distance from the terminal tendon insertion to the nail matrix was ascertained using precision calipers, an optical microscope, and autocad(®) software for windows. Twenty-five great toes were placed in a neutral formalin solution and further analysed by histological longitudinal-sections. The specimens were stained with haematoxylin and eosin and examined microscopically to determine the presence of the extensor hallucis longus tendon along the dorsal aspect of the distal phalanx of each great toe. The main result we found in great toes was that the extensor tendon is between the matrix and the phalanx and extends dorsally to the distal aspect of the distal phalanx in all, 100%, specimens. The nail matrix of the great toe is not attached to the periosteum of the dorsal aspect of the base of the distal phalanx as is the case for fingers, because the extensor hallucis tendon is plantar or directly underneath the nail matrix and the tendon is dorsal to the bone. We have found that the extensor tendon is between the matrix and the phalanx and extends dorsally to the distal aspect of the distal phalanx. The nail matrix of the great toe is not attached to the periosteum of the dorsal aspect of the base of distal phalanx as is the case in fingers, because the extensor hallucis tendon is plantar or directly underneath the nail matrix and the tendon is dorsal to the bone. Our anatomic study demonstrates that the proximal limit of the matrix and nail bed of the human great toe are dorsal and

  2. Anatomical Study of the Neurovascular in Flexor Hallucis Longus Tendon Transfers.

    PubMed

    Mao, Haijiao; Dong, Wenwei; Shi, Zengyuan; Yin, Weigang; Xu, Dachuan; Wapner, Keith L

    2017-10-27

    The transfer of the flexor hallucis longus tendon or flexor digitorum longus tendon is frequently used for the treatment of posterior tibial tendon insufficiency or chronic Achilles tendinopathy. According to several anatomical studies, harvesting the flexor hallucis longus (FHL) tendon may cause nerve injury. Sixty-eight embalmed feet were dissected and anatomically classified to define the relationship between Henry's knot and the plantar nerves. Two different configurations were identified. In Pattern 1, which was observed in 64 specimens (94.1%), the distance between the medial plantar nerve and Henry's knot was 5.96 mm (range, 3.34 to 7.84, SD = 1.12). In Pattern 2, which was observed in 4 specimens (5.9%), there was no distance between the medial plantar nerve (MPN) and Henry's knot. No statistically significant difference was observed according to gender or side (p > 0.05). A retraction was performed to harvest the FHL through the posteromedial hindfoot incision using a single minimally invasive technique, and the medial and lateral plantar nerve lesions were scrupulously assessed. In conclusion, medial and lateral plantar nerve injuries did not occur more frequently, even after performing a single minimally invasive incision to harvest the FHL tendon, due to the large distance between the FHL tendon and the medial and lateral plantar nerves.

  3. [Reconstruction of chronic Achilles tendon rupture with flexor hallucis longus tendon harvested using a minimally invasive technique].

    PubMed

    Miao, Xudong; Wu, Yongping; Tao, Huimin; Yang, Disheng

    2011-07-01

    To evaluate the effectiveness of flexor hallucis longus tendon harvested using a minimally invasive technique in reconstruction of chronic Achilles tendon rupture. Between July 2006 and December 2009, 22 patients (22 feet) with chronic Achilles tendon rupture were treated, including 16 males and 6 females with a median age of 48 years (range, 28-65 years). The disease duration was 27-1,025 days (median, 51 days). Twenty-one patients had hooflike movement's history and 1 patient had no obvious inducement. The result of Thompson test was positive in 22 cases. The score was 53.04 +/- 6.75 according to American Orthopedic Foot and Ankle Society (AOFAS) ankle and hindfoot score system. MRI indicated that the gap of the chronic Achilles tendon rupture was 4.2-8.0 cm. A 3 cm-long incision was made vertically in the plantar aspect of the midfoot and a 1 cm-long transverse incision was made in a plantar flexor crease at the base of the great toe to harvest flexor hallucis longus tendon. The flexor hallucis longus tendon was 10.5-13.5 cm longer from tuber calcanei to the end of the Achilles tendon, and then the tendon was fixed to the tuber calcanei using interface screws or anchor nail after they were woven to form reflexed 3-bundle and sutured. Wound healed by first intention in all patients and no early complication occurred. Twenty-two patients were followed up 12-42 months (mean, 16.7 months). At 12 months after operation, The AOFAS ankle and hindfoot score was 92.98 +/- 5.72, showing significant difference when compared with that before operation (t= -40.903, P=0.000). The results were excellent in 18 cases, good in 2 cases, and fair in 2 cases with an excellent and good rate of 90.9%. No sural nerve injury, posterior tibial nerve injury, plantar painful scar, medial plantar nerve injury, and lateral plantar nerve injury occurred. Chronic Achilles tendon rupture reconstruction with flexor hallucis longus tendon harvested using a minimally invasive technique offers a

  4. Endoscopic-assisted Repair of Neglected Rupture or Rerupture After Primary Repair of Extensor Hallucis Longus Tendon.

    PubMed

    Lui, Tun Hing; Chang, Joseph Jeremy; Maffulli, Nicola

    2016-03-01

    Rerupture of the extensor hallucis longus tendon after primary repair and neglected rupture of the tendon poses surgical challenges to orthopedic surgeons. Open exploration and repair of the tendon ends usually requires large incision and extensive dissection. This may induce scarring and adhesion around the repaired tendon. Endoscopic-assisted repair has the advantage of minimally invasive surgery including less soft tissue trauma and scar formation and better cosmetic result. The use of Krackow locking suture and preservation of the extensor retinacula allow early mobilization of the great toe.

  5. Arthroscopic treatment of tenosynovitis of the flexor hallucis longus tendon.

    PubMed

    Corte-Real, Nuno Manuel; Moreira, Rodrigo Manuel; Guerra-Pinto, Francisco

    2012-12-01

    Tenosynovitis of the flexor hallucis longus (FHL) tendon is a condition typically found in ballet dancers and sometimes in soccer players and is related to chronic overuse. A traumatic cause for this situation, such as an ankle sprain, is considered rare. In case of failure of conservative treatment, the tendon can be surgically released, which is usually done through an open procedure. This article presents the results of an arthroscopic release of the FHL. Twenty-seven patients underwent surgery for FHL tenosynovitis over a period of 18 months. The mean age of the patients was 34 years. All patients related the onset of the condition with an ankle sprain. Eighteen patients were on worker's compensation and five had sport-related accidents. None of the patients was a professional athlete or a ballet dancer. The mean follow-up was 32 months. The outcome was measured with a satisfaction questionnaire and with the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scoring system. The mean postoperative AOFAS score was 89 with 70% excellent or good results. Mean satisfaction rate was 4 (range, 0 to 5); 89% of the patients would undergo the procedure again. Twenty-two patients (81%) returned to the same level of activity in work and sports. A complication rate of 18% (five patients) and reoperation rate of 4% (one patient) were found. Arthroscopic release of the FHL tendon was a valid procedure. It was a minimally invasive surgery that allowed good visualization of the involved structures and yielded good results. This condition can be related to trauma and is not an exclusive disease of ballet dancers or overuse.

  6. Z-plasty of the flexor hallucis longus tendon at tarsal tunnel for checkrein deformity.

    PubMed

    Lee, Jae Hoon; Kim, Young Jun; Baek, Jong Hun; Kim, Dong Hee

    2016-12-01

    To review the outcome of Z-plasty of the flexor hallucis longus (FHL) tendon at the tarsal tunnel for checkrein deformity in 8 patients. Records of 6 males and 2 females aged 14 to 67 (mean, 39.5) years who underwent Z-plasty (lengthening) of the FHL tendon at the tarsal tunnel for checkrein deformity in the first and second toes by a single surgeon were reviewed. All patients had undergone 3 months of conservative treatment. The mean time from injury to surgical treatment was 8.4 (range, 5-12) months. All patients had associated injuries including distal tibiofibular fracture (n=6), distal fibular fracture (n=1), and crush injury aroundthe ankle (n=1); they were treated with intramedullary nailing (n=6), long leg splinting (n=1), and short leg splinting (n=1). After a mean follow-up of 3.4 (range, 1-7) years, the FHL tendon was lengthened by a mean of 1.7 (range, 1.6-1.8) cm, and the mean American Orthopedic Foot and Ankle Society hallux score increased from 59 (range, 52-67) to 89 (range, 80-90). No patient had recurrence, nerve injury, or tarsal tunnel syndrome, although one patient had sensory disturbance of the posterior tibial nerve in the forefoot, which resolved spontaneously at week 2. Z-plasty of the FHL tendon at the tarsal tunnel is a viable option for correction of checkrein deformity.

  7. Arthroscopic Release of Flexor Hallucis Longus Tendon Sheath in Female Ballet Dancers: Dynamic Pathology, Surgical Technique, and Return to Dancing Performance.

    PubMed

    Funasaki, Hiroki; Hayashi, Hiroteru; Sakamoto, Kanako; Tsuruga, Rei; Marumo, Keishi

    2015-12-01

    Stenosing tenosynovitis of the flexor hallucis longus (FHL) tendon is known as a major overuse lesion in female dancers. We describe arthroscopic surgical techniques in relation to the dynamic pathology of the disease. Crepitus and pain on moving the great toe with the ankle in plantar flexion on preoperative examination confirm the diagnosis of FHL stenosing tenosynovitis even if the os trigonum is not evident. The ankle is approached through standard posterolateral and posteromedial portals. A 4.0-mm-diameter 30° arthroscope is used. Soft tissues around the talus are cleared with a motorized shaver and a radiofrequency device. The posterior aspects of the talus, os trigonum, and FHL tendon surrounded by the tendon sheath are visualized. The dynamic pathology of the FHL tendon is well observed on passive motion of the great toe. The prominent bone fragment of the talus is removed and the tendon sheath is cut with a retrograde knife and a motorized shaver from the superior border down to the entrance of the fibro-osseous tunnel. Arthroscopic release of the FHL tendon sheath is a useful and easy method to directly approach the dynamic pathology of FHL tenosynovitis in female ballet dancers.

  8. Anatomical feasibility study of flexor hallucis longus transfer in treatment of Achilles tendon and posteromedial portal of ankle arthroscopy.

    PubMed

    Mao, Haijiao; Wang, Linger; Dong, Wenwei; Liu, Zhenxin; Yin, Weigang; Xu, Dachuan; Wapner, Keith L

    2018-04-16

    The aim of this study was to evaluate the occurrence of anatomical variations of the musculotendinous junction of the flexor hallucis longus (FHL) muscle, the relationship between FHL tendon or muscle and the tibial neurovascular bundle at the level of the posterior ankle joint in human cadavers. Seventy embalmed feet from 20 male and 15 female cadavers, the cadavers' mean age was 65.4 (range from 14 to 82) years, were dissected and anatomically classified to observe FHL muscle morphology define the relationship between FHL tendon or muscle and the tibial neurovascular bundle. The distance between the musculotendinous junction and the relationship between FHL tendon or muscle and the tibial neurovascular bundle was determined. Three morphology types of FHL muscle were identified: a long lateral and shorter medial muscle belly, which was observed in 63 specimens (90%); equal length medial and lateral muscle bellies, this variant was only observed in five specimens (7.1%); one lateral and no medial muscle belly, which was observed in two specimens (2.9%). No statistically significant difference was observed according to gender or side (p > 0.05). Two patterns were identified and described between FHL tendon or muscle and the tibial neurovascular bundle. Pattern 1, the distance between the neurovascular bundle and FHL tendon was 3.46 mm (range 2.34-8.84, SD = 2.12) which was observed in 66 specimens (94.3%); Pattern 2, there was no distance which was observed in four specimens (5.7%). Knowing FHL muscle morphology, variations provide new important insights into secure planning and execution of a FHL transfer for Achilles tendon defect as well as for the interpretation of ultrasound and magnetic resonance images. With posterior arthroscopic for the treatment of various ankle pathologies, posteromedial portal may be introduced into the posterior aspect of the ankle without gross injury to the tibial neurovascular structures because of the gap between the

  9. Evidence of isometric function of the flexor hallucis longus muscle in normal gait.

    PubMed

    Kirane, Y M; Michelson, J D; Sharkey, N A

    2008-01-01

    Studying mechanics of the muscles spanning multiple joints provides insights into intersegmental dynamics and movement coordination. Multiarticular muscles are thought to function at "near-isometric" lengths to transfer mechanical energy between the adjacent body segments. Flexor hallucis longus (FHL) is a multiarticular flexor of the great toe; however, its potential isometric function has received little attention. We used a robotic loading apparatus to investigate FHL mechanics during simulated walking in cadaver feet, and hypothesized that physiological force transmission across the foot can occur with isometric FHL function. The extrinsic foot tendons, stripped of the muscle fibers, were connected to computer-controlled linear actuators. The FHL activity was controlled using force-feedback (FC) based upon electromyographic data from healthy subjects, and subsequently, isometric positional feedback (PC), maintaining the FHL myotendinous junction stationary during simulated walking. Tendon forces and excursions were recorded, as were the strains within the first metatarsal. Forces in the metatarsal and metatarsophalangeal joint were derived from these strains. The FHL tendon excursion under FC was 6.57+/-3.13mm. The forces generated in the FHL tendon, metatarsal and metatarsophalangeal joint with the FHL under isometric PC were not significantly different in pattern from FC. These observations provide evidence that physiological forces could be generated along the great toe with isometric FHL function. A length servo mechanism such as the stretch reflex could likely control the isometric FHL function during in vivo locomotion; this could have interesting implications regarding the conditions of impaired stretch reflex such as spastic paresis and peripheral neuropathies.

  10. Incidence and Association of CT Findings of Ankle Tendon Injuries in Patients Presenting With Ankle and Hindfoot Fractures.

    PubMed

    Golshani, Ashkahn; Zhu, Liang; Cai, Chunyan; Beckmann, Nicholas M

    2017-02-01

    Tendon injuries are a commonly encountered finding in ankle CT examinations performed for fractures. This study was designed to identify the incidence and associations of tendon injuries in ankle CT examinations performed for fractures. A retrospective review was performed of 410 patients who underwent ankle CT during a 6-year period. Tendon injuries were common, seen in 25% of all ankle CT examinations. Tendon subluxation-dislocation accounted for most of the tendon injuries (77 of 196 total injuries). Pilon fractures carried 2.2 times increased risk of tibialis posterior tendon injury (p = 0.0094). Calcaneus fractures carried 11.86 times increased risk of peroneus brevis tendon and 10.71 times increased risk of peroneus longus tendon injury (p < 0.0001). Calcaneus fractures also carried 5.21 times increased risk of flexor hallucis longus tendon injury (p = 0.0024). Talus fracture was associated with injury to all flexor compartment tendons. Talus fractures carried 3.43 times increased risk of tibialis posterior tendon injury (p < 0.0001), 4.51 times increased risk of flexor digitorum longus tendon injury (p = 0.0005), and 6.97 times increased risk of flexor hallucis longus tendon injury (p < 0.0001). Calcaneal fractures are prone to peroneal tendon injury, and talus fractures are prone to flexor tendon injury. In patients with pilon fractures, it is important to look for tibialis posterior tendon injury, specifically for entrapment. Overall, the most common type of injury is tendon malalignment, so it is imperative to know the normal tendon paths and associated bony landmarks to identify tendon injury.

  11. Effects of Postmortem Freezing on Passive Properties of Rabbit Extensor Digtorum Longus Muscle Tendon Complex

    DTIC Science & Technology

    1993-06-14

    AD-A266 429 INSTITUTE REPORT NO. 483 Effects of Postmortem Freezing on Passive Properties of Rabbit Extensor Digtorum Longus Muscle Tendon Complex D...Extensor Digtorum Longus Muscle Tendon Complex -- Paul H. Leitschuh, Tammy J. Doherty, Dean C. Taylor, Daniel E. Brooks, John B. Ryan This document has...ABSTRACT The tensile properties of the extensor digitorum longus muscle tendon unit (EDL MTU) were studied in 16 white male New Zealand rabbits in both

  12. Initial experience with visualizing hand and foot tendons by dual-energy computed tomography.

    PubMed

    Deng, Kai; Sun, Cong; Liu, Cheng; Ma, Rui

    2009-01-01

    To assess the feasibility of visualizing hand and foot tendons by dual-energy computed tomography (CT). Twenty patients who suffered from hand or feet pains were scanned on dual-source CT (Definition, Forchheim, Germany) with dual-energy mode at tube voltages of 140 and 80 kV and a corresponding ratio of 1:4 between tube currents. The reconstructed images were postprocessed by volume rendering techniques (VRT) and multiplanar reconstruction (MPR). All of the suspected lesions were confirmed by surgery or follow-up studies. Twelve patients (total of 24 hands and feet, respectively) were found to be normal and the other eight patients (total of nine hands and feet, respectively) were found abnormal. Dual-energy techniques are very useful in visualizing tendons of the hands and feet, such as flexor pollicis longus tendon, flexor digitorum superficialis/profundus tendon, Achilles tendon, extensor hallucis longus tendon, and extensor digitorum longus tendon, etc. It can depict the whole shape of the tendons and their fixation points clearly. Peroneus longus tendon in the sole of the foot was not displayed very well. The distal ends of metacarpophalangeal joints with extensor digitoium tendon and extensor pollicis longus tendon were poorly shown. The lesions of tendons such as the circuitry, thickening, and adherence were also shown clearly. Dual-energy CT offers a new method to visualize tendons of the hand and foot. It could clearly display both anatomical structures and pathologic changes of hand and foot tendons.

  13. Surgical treatment for partial rupture of the distal biceps tendon using palmaris longus tendon graft: A case report.

    PubMed

    Ozasa, Yasuhiro; Wada, Takuro; Iba, Kousuke; Yamashita, Toshihiko

    2018-03-08

    We report a case of a partial rupture of the distal biceps tendon that was surgically treated using a palmaris longus tendon graft. A 58-year-old man complained of increasing pain with resisted elbow flexion and supination in the antecubital fossa. Magnetic resonance imaging revealed the irregularity of a distal attachment of the biceps brachii and peripheral signal changes. We diagnosed a partial rupture of the distal biceps tendon. Because conservative treatment failed, surgical treatment was performed through a single anterior approach. The insertion of the tendon was partially ruptured at the radial tuberosity. After the involved site was debrided, the palmaris longus tendon was grafted with suture anchors to reinforce the remaining tendon. Postoperative immobilization was not performed, and all moves were freed after 3 weeks. At the 6-year postoperative follow-up, the patient no longer experienced pain and returned to his original job without any limitations. Copyright © 2018 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  14. Chronic triceps insufficiency managed with extensor carpi radialis longus and palmaris longus tendon grafts.

    PubMed

    Singh, Dhanpal; Kumar, K Arun; Dinesh, Mc; Raj, Ranju

    2012-03-01

    Chronic triceps insufficiency, causing prolonged disability, occurs due to a missed diagnosis of an acute rupture. We report a 25 year old male with history of a significant fall sustaining multiple injuries. Since then, he had inability in extending his right elbow for which he sought intervention after a year. Diagnosis of triceps rupture was made clinicoradiologically and surgery was planned. Intraoperative findings revealed a deficient triceps with a fleck of avulsed bone from olecranon. Ipsilateral double tendon graft including extensor carpi radialis longus and palmaris longus were anchored to triceps and secured with the olecranon. Six-months follow revealed a complete active extension of elbow and a full function at the donor site.

  15. Step Cut Lengthening: A Technique for Treatment of Flexor Pollicis Longus Tendon Rupture.

    PubMed

    Chong, Chew-Wei; Chen, Shih-Heng

    2018-04-01

    Reconstruction of a tendon defect is a challenging task in hand surgery. Delayed repair of a ruptured flexor pollicis longus (FPL) tendon is often associated with tendon defect. Primary repair of the tendon is often not possible, particularly after debridement of the unhealthy segment of the tendon. As such, various surgical treatments have been described in the literature, including single-stage tendon grafting, 2-stage tendon grafting, flexor digitorum superficialis tendon transfer from ring finger, and interphalangeal joint arthrodesis. We describe step cut lengthening of FPL tendon for the reconstruction of FPL rupture. This is a single-stage reconstruction without the need for tendon grafting or tendon transfer. To our knowledge, no such technique has been previously described.

  16. Small flake, big problem: an unreported cause of extensor pollicis longus tendon rupture.

    PubMed

    Durrant, C A T; Bantick, G

    2010-01-01

    Fracture of the base of the third metacarpal with associated avulsion of the extensor carpi radialis brevis tendon is a rare injury. We report such a fracture and the unusual resulting complication of division of the extensor pollicis longus tendon by the avulsed bony fragment. Careful monitoring using lateral radiographs is needed to make the diagnosis and displacement of the avulsed fragment warrants open reduction and internal fixation.

  17. Treatment of mallet finger deformity with a modified palmaris longus tendon graft through a bone tunnel.

    PubMed

    Liu, Zengbing; Ma, Kai; Huang, Dong

    2018-01-01

    To investigate the clinical effect of treating mallet finger deformity using a modified palmaris longus tendon graft through a bone tunnel. Altogether, 21 patients with mallet finger deformity (16 men, 5 women; average age 31 years, range 19-47 years) were treated with a modified palmaris longus tendon graft through a bone tunnel during 18 months (2014-2016). Four index fingers, seven middle fingers, eight ring fingers, and two little fingers were treated for four cutting injuries, eleven finger sprains, four crush injuries, and two twist injuries (7 open and 14 closed injuries). Duration from injury to surgery was 9 h to 13 weeks. Three patients underwent surgery after 6 weeks of unsuccessful conservative treatment. No tendon was attached to the extensor tendon insertion in 16 patients, and 5 had residual tendon of <0.2 cm attached. All patients had distal segment flexion deformity and dorsiflexion disorder. Surgery comprised transverse penetration and vertical drilling of the base of the distal phalanx (2.0 and 2.5 mm diameter drills). Equal shallow semitendinosus pieces of the palmaris longus tendon (4 cm) were obtained from the sagittal end and were passed through a dorsal bone hole, emerging from a transverse bone hole. The two bundles were sutured to the main tendon. Tension was adjusted, and the broken ends were sutured. The distal interphalangeal joints were fixed in hyperextension. All patients were followed for 7-16 months (average 6.0 ± 0.3 months) postoperatively. All 21 patients had grade A wound healing, with no complications (e.g., necrotic wound, recurrence, joint stiffness). The mallet finger deformity was corrected with good appearance, no obvious abnormalities, and satisfactory flexion and extension. Two patients had a superficial wound infection. Each recovered after symptomatic treatment. One patient had a mild result, with limited extension. There were no recurrences. Results were evaluated according to Patel et al.'s system, which revealed

  18. [Reconstruction of the extensor pollicis longus tendon by transposition of the extensor indicis tendon].

    PubMed

    Loos, A; Kalb, K; Van Schoonhoven, J; Landsleitner Dagger, B

    2003-12-01

    Rupture of the extensor pollicis longus-tendon (EPL) is a frequent complication after distal radius fractures. Other traumatic and non-traumatic reasons for this tendon lesion are known, including a theory about a disorder in the blood supply to the tendon itself. We examined 40 patients after reconstruction of the EPL-tendon in a mean follow-up time of 30 months. All patients were clinically examined and a DASH questionnaire was answered by all patients. The method to reconstruct the EPL-tendon was the transposition of the extensor indicis-tendon. After the operations the thumb was put in a splint for four weeks in a "hitch-hiker's-position". 31 ruptures of the tendon (77.5 %) were a result of trauma. In 20 of them (50 %) a distal radius fracture had occurred. Clinical examination included measurements of the movement of the thumb- and index-finger joints, the grip strength and the maximal span of the hand. Significant differences were not found. The isolated extension of the index finger was possible in all patients. But it was reduced in ten cases which represent 25 %. Our results were evaluated by the Geldmacher score to evaluate the reconstruction of the EPL-tendon. 20 % excellent, 65 % good, 12.5 % fair and 2.5 % poor results were reached. The Geldmacher score was used critically. We suggest its modification for the evaluation of thumb abduction. The DASH score reached a functional value of ten points which represents a very good result. In conclusion the extensor indicis-transposition is a safe method to reconstruct the EPL-tendon. Its substantial advantage is taking a healthy muscle as the motor, thereby avoiding the risk of using a degenerated muscle in late tendon reconstruction. A powerful extension of the index finger will be maintained by physical education. Generally, the loss of the extension of the index finger is negligible. It does not disturb the patients. But it has to be discussed with the patient before the operation.

  19. Muscle-tendon glucose uptake in Achilles tendon rupture and tendinopathy before and after eccentric rehabilitation: Comparative case reports.

    PubMed

    Masood, Tahir; Kalliokoski, Kari; Bojsen-Møller, Jens; Finni, Taija

    2016-09-01

    Achilles tendon rupture (ATR) is the most common tendon rupture injury. The consequences of ATR on metabolic activity of the Achilles tendon and ankle plantarflexors are unknown. Furthermore, the effects of eccentric rehabilitation on metabolic activity patterns of Achilles tendon and ankle plantarflexors in ATR patients have not been reported thus far. We present a case study demonstrating glucose uptake (GU) in the Achilles tendon, the triceps surae, and the flexor hallucis longus of a post-surgical ATR patient before and after a 5-month eccentric rehabilitation. At baseline, three months post-surgery, all muscles and Achilles tendon displayed much higher GU in the ATR patient compared to a healthy individual despite lower plantarflexion force. After the rehabilitation, plantarflexion force increased in the operated leg while muscle GU was considerably reduced. The triceps surae muscles showed similar values to the healthy control. When compared to the healthy or a matched patient with Achilles tendon pain after 12 weeks of rehabilitation, Achilles tendon GU levels of ATR patient remained greater after the rehabilitation. Past studies have shown a shift in the metabolic fuel utilization towards glycolysis due to immobilization. Further research, combined with immuno-histological investigation, is needed to fully understand the mechanism behind excessive glucose uptake in ATR cases. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Peroneal perforator-based peroneus longus tendon and sural neurofasciocutaneous composite flap transfer for a large soft-tissue defect of the forearm: A case report.

    PubMed

    Hayashida, Kenji; Saijo, Hiroto; Fujioka, Masaki

    2018-01-01

    We describe the use of a composite flap composed of a sural neurofasciocutaneous flap and a vascularized peroneus longus tendon for the reconstruction of severe composite forearm tissue defects in a patient. A 43-year-old man had his left arm caught in a conveyor belt resulting in a large soft-tissue defect of 18 × 11 cm over the dorsum forearm. The extensor carpi radialis, superficial radial nerve, and radial artery were severely damaged. A free neurofasciocutaneous composite flap measuring 16 × 11 cm was outlined on the patient's left lower leg to allow simultaneous skin, tendon, nerve, and artery reconstruction. The flap, which included the peroneus longus tendon, was elevated on the subfascial plane. After the flap was transferred to the recipient site, the peroneal artery was anastomosed to the radial artery in a flow-through manner. The vascularized tendon graft with 15 cm in length was used to reconstruct the extensor carpi radialis longus tendon defect using an interlacing suture technique. As the skin paddle of the sural neurofasciocutaneous flap and the vascularized peroneus longus tendon graft were linked by the perforator and minimal fascial tissue, the skin paddle was able to rotate and slide with comparative ease. The flap survived completely without any complications. The length of follow-up was 12 months and was uneventful. Range of motion of his left wrist joint was slightly limited to 75 degrees. This novel composite flap may be useful for reconstructing long tendon defects associated with extensive forearm soft tissue defects. © 2016 Wiley Periodicals, Inc.

  1. Half-peroneus-longus-tendon graft augmentation for unqualified hamstring tendon graft of anterior cruciate ligament reconstruction.

    PubMed

    Liu, Chung-Ting; Lu, Yung-Chang; Huang, Chang-Hung

    2015-09-01

    In some situations, harvested hamstring tendon grafts are not qualified for anterior cruciate ligament (ACL) reconstruction. This study aimed to present a reinforcing method with additional half peroneus longus tendon (half-PLT) graft augmentation. Eight cases underwent ACL reconstruction with unqualified hamstring tendon grafts (diameter <7 mm) and were salvaged by additional half-PLT graft augmentation. The pivot shift test and KT-1000 tests were performed 3 years after surgery. Functional evaluation of subjective International Knee Documentation Committee (IKDC) and Lysholm scores was also done. In addition, Foot and Ankle Disability Index (FADI) scores were used to evaluate the function of the ankle donor site. The diameter of unqualified four-strand hamstring tendon grafts was 6.2 mm on average (range, 6.0-6.5 mm). The average diameter of hamstring grafts with half-PLT augmentation was 9.6 mm (range, 9.5-10.0 mm). The pivot shift test was negative in all patients. No significant differences between normal and abnormal knees were found by KT-1000. The average IKDC score was 86.0 (range, 83 to 89), and the average Lysholm score was 84.4 (range, 80-90). The average FADI score for the donor sites of half-PLT was 135.8 (range, 134-136). Additional half-PLT can successfully and safely reinforce unqualified hamstring tendon grafts for ACL reconstruction.

  2. [Rupture of the tendon of the tibialis anterior muscle : Etiology, clinical symptoms and treatment].

    PubMed

    Waizy, H; Bouillon, B; Stukenborg-Colsman, C; Yao, D; Ettinger, S; Claassen, L; Plaass, C; Danniilidis, K; Arbab, D

    2017-12-01

    Ruptures of the tendon of the tibialis anterior muscle tend to occur in the context of degenerative impairments. This mainly affects the distal avascular portion of the tendon. Owing to the good compensation through the extensor hallucis longus and extensor digitorum muscles, diagnosis is often delayed. In addition to the clinical examination, magnetic resonance inaging (MRI) diagnostics are of particular importance, although damage or rupture of the tendon can also be demonstrated sonographically. Therapeutic measures include conservative or operative measures, depending on the clinical symptoms. Conservative stabilization of the ankle can be achieved by avoiding plantar flexion using a peroneal orthosis or an ankle-foot orthosis. Subsequent problems, such as metatarsalgia or overloading of the medial foot edge can be addressed by insoles or a corresponding shoe adjustment. An operative procedure is indicated when there is corresponding suffering due to pressure and functional impairment. The direct end-to-end reconstruction of the tendon is only rarely possible in cases of delayed diagnosis due to the degenerative situation and the retraction of the tendon stumps. Depending on the defect size and the tendon quality, various operative techniques, such as rotationplasty, free transplants or tendon transfer can be used.

  3. Intermediate term follow-up of calcaneal osteotomy and flexor digitorum longus transfer for treatment of posterior tibial tendon dysfunction.

    PubMed

    Fayazi, Amir H; Nguyen, Hoan-Vu; Juliano, Paul J

    2002-12-01

    Twenty-three patients with stage II posterior tibial tendon dysfunction who had failed non-surgical therapy were treated with flexor digitorum longus transfer and calcaneal osteotomy. At latest follow-up averaging 35 +/- 7 months (range, 24 to 51 months), 22 patients (96%) were subjectively "better" or "much better." No patient had difficulty with shoe wear; however, four patients (17%) required routine orthotic use consisting of a molded shoe insert. AOFAS scores were available on 21 patients and improved from a preoperative mean of 50 +/- 14 (range, 27 to 85) to a postoperative mean of 89 +/- 10 (range, 70 to 100). Our experience, at an intermediate date follow-up is that calcaneal osteotomy and flexor digitorum longus transfer is a safe and effective form of treatment for stage II posterior tibial tendon dysfunction.

  4. The athlete's foot: the grey zone behind the ankle.

    PubMed

    van Giffen, Nicolien; Seil, Romain; Pape, Diederich; Nührenbörger, Christian

    2009-01-01

    Posterior ankle and heel pain is common among athletes. The most common injury in this region is that of the Achilles tendon. However, besides the Achilles tendon, pain can originate from a retrocalcaneal bursitis, posterior impingement syndrome, os trigonum syndrome, or flexor hallucis longus tenosynovitis. These pathologies often caused by overuse, but can also occur after trauma. With careful examination, and the help of MRI imaging, the distinction can be made among these pathologies and the more common Achilles tendon problems. Like most overuse injuries, the majority of cases of retrocalcaneal bursitis, posterior impingement, flexor hallucis longus tenosynovitis respond to conservative treatment. However, when this fails, open or arthroscopic surgery can be proposed. Arthroscopy is less aggressive than open surgery, with the added advantage of less patient morbidity, less post-operative pain, and early functional rehabilitation. It is becoming the surgery of choice, especially among athletes.

  5. In vivo fascicle behavior of the flexor hallucis longus muscle at different walking speeds.

    PubMed

    Péter, A; Hegyi, A; Finni, T; Cronin, N J

    2017-12-01

    Ankle plantar flexor muscles support and propel the body in the stance phase of locomotion. Besides the triceps surae, flexor hallucis longus muscle (FHL) may also contribute to this role, but very few in vivo studies have examined FHL function during walking. Here, we investigated FHL fascicle behavior at different walking speeds. Ten healthy males walked overground at three different speeds while FHL fascicle length changes were recorded with ultrasound and muscle activity was recorded with surface electromyography (EMG). Fascicle length at heel strike at toe off and at peak EMG activity did not change with speed. Range of FHL fascicle length change (3.5-4.5 and 1.9-2.9 mm on average in stance and push-off phase, respectively), as well as minimum (53.5-54.9 and 53.8-55.7 mm) and maximum (58-58.4 and 56.8-57.7 mm) fascicle length did not change with speed in the stance or push-off phase. Mean fascicle velocity did not change in the stance phase, but increased significantly in the push-off phase between slow and fast walking speeds (P=.021). EMG activity increased significantly in both phases from slow to preferred and preferred to fast speed (P<.02 in all cases). FHL muscle fascicles worked near-isometrically during the whole stance phase (at least during slow walking) and operated at approximately the same length at different walking speeds. FHL and medial gastrocnemius (MG) have similar fiber length to muscle belly length ratios and, according to our results, also exhibit similar fascicle behavior at different walking speeds. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Semitendinosus Tendon Autograft for Reconstruction of Large Defects in Chronic Achilles Tendon Ruptures.

    PubMed

    Dumbre Patil, Sampat Shivajirao; Dumbre Patil, Vaishali Sampat; Basa, Vikas Rajeshwarrao; Dombale, Ajay Birappa

    2014-07-01

    Chronic Achilles tendon ruptures are associated with considerable functional morbidity. When treated operatively, debridement of degenerated tendon ends may create large defects. Various procedures to reconstruct large defects have been described. We present a simple technique in which an autologous semitendinosus tendon graft is used to reconstruct defects larger than 5 cm in chronic Achilles tendon ruptures. The purpose of this study was to describe our operative technique and its functional outcome. Achilles ruptures of more than 6 weeks duration were considered for the study. We treated 35 patients (20 males, 15 females) with symptomatic chronic Achilles tendon ruptures. The mean age was 47.4 years (range, 30 to 59). The smallest defect that we had reconstructed was 5 cm, and the largest was 9 cm in length. The average follow-up duration was 30.7 months (range, 20 to 42). Postoperatively, the strength of gastrocsoleus was measured by manual muscle testing (MMT) in non-weight-bearing and weight-bearing positions. All operated patients showed satisfactory functional outcome, good soft tissue healing, and no reruptures. The preoperative weight-bearing MMT of 2/5 improved to 4/5 or 5/5 postoperatively. In all patients, postoperative non-weight-bearing MMT was 5/5. All patients returned to their prerupture daily activity. We present a technique that is simple, with low morbidity. We believe it is a valuable option especially when allografts are not available. It is inexpensive as suture anchors or tenodesis screws are not used. This can be a useful option if other tendons (flexor hallucis longus, peroneus brevis, etc) are not available for transfer. Level IV, retrospective case series. © The Author(s) 2014.

  7. Peroneus longus tears associated with pathology of the os peroneum.

    PubMed

    Stockton, Kristopher G; Brodsky, James W

    2014-04-01

    There is a range of different types of tears and pathology of the peroneal tendons. One of the least common types is the tear of the peroneus longus associated with fracture, enlargement, or entrapment at the cuboid tunnel of the os peroneum. The purpose of this study was to evaluate the pathologic patterns of these uncommon peroneal tendon tears, to review the treatment, and to report the patient outcomes following treatment with excision of the os peroneum, debridement, and tenodesis of the peroneus longus to the peroneus brevis. A 5-year retrospective review of all patients with peroneal tendon tears identified 12 patients operatively treated for peroneus longus tendon tears with associated pathology of the os peroneum, and in whom there was a viable peroneus brevis. All patients were treated with an operative procedure consisting of excision of the os peroneum, debridement, and tenodesis of the peroneus longus to the peroneus brevis. Mean age was 51.5 (range, 33 to 73) years, including 7 males and 5 females. Operative and radiographic records were reviewed to characterize the nature of the peroneus longus tears and associated pathology. Preoperative and postoperative AOFAS hindfoot, SF-36 questionnaires, and Visual Analog Scale (VAS) pain scores were compiled and patient records were reviewed for complications. Mean follow-up after surgery was 63.3 (range, 12 to 114) months. All of the patients had an os peroneum associated with a complex, irreparable tear of the peroneus longus tendon. The peroneus longus was typically enlarged, fibrotic, and adhered to the surrounding tissues. In 8 patients, the peroneus longus tendon tear was associated with a fracture of the os peroneum, and in 4 patients with an enlarged and entrapped os peroneum which prevented movement at the cuboid tunnel. Of the 12 patients, 9 had partial tears of the peroneus brevis, which were treated with debridement and suture repair. AOFAS hindfoot scores increased from a preoperative mean of 61

  8. Reconstruction for chronic Achilles tendinopathy: comparison of flexor hallucis longus (FHL) transfer versus V-Y advancement.

    PubMed

    Staggers, Jackson R; Smith, Kenneth; de C Netto, Cesar; Naranje, Sameer; Prasad, Krishna; Shah, Ashish

    2018-04-01

    Several operative techniques exist for Achilles tendinopathy. The purpose of our study was to compare the clinical and functional outcomes of flexor hallucis longus (FHL) transfer and V-Y advancement for the treatment of chronic insertional Achilles tendinopathy. Retrospective chart review from 2010 to 2016 of patients that underwent FHL transfer or V-Y advancement for chronic insertional Achilles tendinopathy. Outcome measures were compared for these two procedures. In total, 46 patients (49 ankles) with a mean age of 55.0 (range 33-73) years. Mean follow-up time 44.7 +/- 25.5 months. FHL group had 21 patients (21 ankles) with 89% satisfaction, 14% complication rate, final VAS of 0.4, final VISA-A of 89.1, subjective strength improvement following surgery of 78%, and 94% would recommend the procedure. V-Y group had 25 patients (28 ankles) with 74% subjective satisfaction, 21% complication rate, final VAS of 1.4, final VISA-A of 78.4, subjective strength improvement following surgery of 67%, and 84% would recommend the procedure. There was no significant difference in any of the results rates between the two groups (p > .05). V-Y advancement is comparable to FHL transfer for the operative management of insertional Achilles tendinopathy. Though our results trend towards less satisfactory results following V-Y advancement, we found high satisfaction rates with similar functional outcomes and complication rates in both operative groups. We suggest considering V-Y advancement as a viable option for the primary treatment of chronic insertional Achilles tendinopathy in patients who may not be an ideal candidate for FHL transfer.

  9. Reconstruction of closed rupture of thumb flexor tendon pulleys with a single free palmaris longus tendon graft: a case report and review of literature.

    PubMed

    Fazilleau, F; Cheval, D; Richou, J; Le Nen, D

    2014-02-01

    Closed rupture of thumb flexor tendon pulleys is extremely rare. Several techniques have already been described for finger pulley reconstruction. Various techniques based on prior anatomic and biomedical studies have been proposed for thumb pulley reconstruction, in which one or two of the three pulleys are replaced. In the present study, we describe an original technique using a single, free palmaris longus (PL) autograft for thumb pulley reconstruction. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  10. Outcome of Lateral Transfer of the FHL or FDL for Concomitant Peroneal Tendon Tears.

    PubMed

    Seybold, Jeffrey D; Campbell, John T; Jeng, Clifford L; Short, Kelly W; Myerson, Mark S

    2016-06-01

    Concomitant tears of the peroneus longus and brevis tendons are rare injuries, with literature limited to case reports and small patient series. Only 1 recent study directly compared the results of single-stage lateral deep flexor transfer, and no previous series objectively evaluated power and balance following transfer. The purpose of this study was to evaluate clinical outcomes, patient satisfaction, and objective power and balance data following single-stage flexor hallucis longus (FHL) and flexor digitorum longus (FDL) tendon transfers for treatment of concomitant peroneus longus and brevis tears. Over an 8-year period (2005-2012), 9 patients underwent lateral transfer of the FHL or FDL tendon for treatment of concomitant peroneus longus and brevis tears. All but 1 patient underwent additional procedures to address hindfoot malalignment or other contributing deformity at the time of surgery. Mean age was 56.9 years, and average body mass index was 27.9. Lateral transfer of the FHL was performed in 5 patients, and FDL transfer performed in 4 with mean follow-up 35.7 months (range: 11-94). Eight of 9 patients completed SF-12 and Foot Function Index (FFI) scores, and 7 returned for range of motion (ROM) and manual strength testing of the involved and normal extremities. These 7 patients also completed force plate balance tests, in addition to peak force and power testing on a PrimusRS machine with a certified physical therapist. All patients were satisfied with the results of the procedure. Mean SF-12 physical and mental scores were 32 and 55, respectively; mean FFI total score was 56.7. No postoperative infections were noted. Two patients continued to utilize orthotics or braces, and 2 patients reported occasional pain with weightbearing activity. Three patients noted mild paresthesias in the distribution of the sural nerve and 2 demonstrated tibial neuritis. All patients demonstrated 4/5 eversion strength in the involved extremity. Average loss of inversion and

  11. Tendon rupture associated with excessive smartphone gaming.

    PubMed

    Gilman, Luke; Cage, Dori N; Horn, Adam; Bishop, Frank; Klam, Warren P; Doan, Andrew P

    2015-06-01

    Excessive use of smartphones has been associated with injuries. A 29-year-old, right hand-dominant man presented with chronic left thumb pain and loss of active motion from playing a Match-3 puzzle video game on his smartphone all day for 6 to 8 weeks. On physical examination, the left extensor pollicis longus tendon was not palpable, and no tendon motion was noted with wrist tenodesis. The thumb metacarpophalangeal range of motion was 10° to 80°, and thumb interphalangeal range of motion was 30° to 70°. The clinical diagnosis was rupture of the left extensor pollicis longus tendon. The patient subsequently underwent an extensor indicis proprius (1 of 2 tendons that extend the index finger) to extensor pollicis longus tendon transfer. During surgery, rupture of the extensor pollicis longus tendon was seen between the metacarpophalangeal and wrist joints. The potential for video games to reduce pain perception raises clinical and social considerations about excessive use, abuse, and addiction. Future research should consider whether pain reduction is a reason some individuals play video games excessively, manifest addiction, or sustain injuries associated with video gaming.

  12. Modified tendon stripper for obtaining palmaris longus tendon graft.

    PubMed

    Aköz, T; Altintaş, H; Civelek, B

    1999-04-01

    Tendon graft harvesting is a challenging part of hand surgery. It is not only a time-consuming procedure but also carries the potential complications associated with it. Various alternatives for this procedure are presented in the literature to overcome these difficulties. In this paper, we are presenting a series of cases in which a newly modified tendon stripper was used for tendon graft harvesting.

  13. [Secondary tendon reconstruction on the thumb].

    PubMed

    Bickert, B; Kremer, T; Kneser, U

    2016-12-01

    Closed tendon ruptures of the thumb that require secondary reconstruction can affect the extensor pollicis longus (EPL), extensor pollicis brevis (EPB) and flexor pollicis longus (FPL) tendons. Treatment of rupture of the EPB tendon consists of refixation to the bone and temporary transfixation of the joint. In the case of preexisting or posttraumatic arthrosis, definitive arthrodesis of the thumb is the best procedure. Closed ruptures of the EPL and FPL tendons at the wrist joint cannot be treated by direct tendon suture. Rupture of the EPL tendon occurs after distal radius fractures either due to protruding screws or following conservative treatment especially in undisplaced fractures. Transfer of the extensor indicis tendon to the distal EPL stump is a good option and free interposition of the palmaris longus tendon is a possible alternative. The tension should be adjusted to slight overcorrection, which can be checked intraoperatively by performing the tenodesis test. Closed FPL ruptures at the wrist typically occur 3-6 months after osteosynthesis of distal radius fractures with palmar plates and are mostly characterized by crepitation and pain lasting for several weeks. They can be prevented by premature plate removal, synovectomy and carpal tunnel release. For treatment of a ruptured FPL tendon in adult patients the options for tendon reconstruction should be weighed up against the less complicated tenodesis or arthrodesis of the thumb interphalangeal joint.

  14. EMG and force production of the flexor hallucis longus muscle in isometric plantarflexion and the push-off phase of walking.

    PubMed

    Péter, Annamária; Hegyi, András; Stenroth, Lauri; Finni, Taija; Cronin, Neil J

    2015-09-18

    Large forces are generated under the big toe in the push-off phase of walking. The largest flexor muscle of the big toe is the flexor hallucis longus (FHL), which likely contributes substantially to these forces. This study examined FHL function at different levels of isometric plantarflexion torque and in the push-off phase at different speeds of walking. FHL and calf muscle activity were measured with surface EMG and plantar pressure was recorded with pressure insoles. FHL activity was compared to the activity of the calf muscles. Force and impulse values were calculated under the big toe, and were compared to the entire pressed area of the insole to determine the relative contribution of big toe flexion forces to the ground reaction force. FHL activity increased with increasing plantarflexion torque level (F=2.8, P=0.024) and with increasing walking speed (F=11.608, P<0.001). No differences were observed in the relative contribution of the force under the big toe to the entire sole between different plantarflexion torque levels (F=0.836, P=0.529). On the contrary, in the push-off phase of walking, peak force under the big toe increased at a higher rate than force under the other areas of the plantar surface (F=3.801, P=0.018), implying a greater relative contribution to total force at faster speeds. Moreover, substantial differences were found between isometric plantarflexion and walking concerning FHL activity relative to that of the calf muscles, highlighting the task-dependant behaviour of FHL. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Success of nonoperative management of adductor longus tendon ruptures in National Football League athletes.

    PubMed

    Schlegel, Theodore F; Bushnell, Brandon D; Godfrey, Jenna; Boublik, Martin

    2009-07-01

    Acute complete ruptures of the proximal adductor longus tendon are rare but challenging injuries to treat. The limited literature supports operative treatment, but data from management of chronic groin pain in athletes indicate that anatomical attachment of the tendon to the pubis may not be required for high-level function. Nonoperative management of complete adductor rupture can provide equal results to surgical repair in terms of return to play in the National Football League. Case series; Level of evidence, 4. Using the National Football League Injury Surveillance System, adductor tendon ruptures documented by magnetic resonance imaging were identified in 19 National Football League players from 1992 to 2004. The team physician for each respective player completed a survey with information about history, physical examination, magnetic resonance imaging findings, treatment, and outcomes. Statistics were analyzed with a Student unpaired t test. Fourteen players were treated nonoperatively, and 5 players were treated with surgical repair using suture anchors. In both groups, all players eventually returned to play in the National Football League. Mean time for return to play was 6.1 +/- 3.1 weeks (range, 3-12 weeks) for the nonoperative group and 12.0 +/- 2.5 weeks (range, 10-16 weeks) for the operative group (P = .001). One player in the operative group suffered the complication of a draining wound and heterotopic ossification. Players represented a variety of positions, and 12 of 19 (63%) had experienced prior symptoms or events. Nonoperative treatment of proximal adductor tendon rupture results in a statistically significantly faster return to play than does operative treatment in athletes competing in the National Football League and avoids the risks associated with surgery while providing an equal likelihood of return to play at the professional level.

  16. Effects of 12-wk eccentric calf muscle training on muscle-tendon glucose uptake and SEMG in patients with chronic Achilles tendon pain.

    PubMed

    Masood, Tahir; Kalliokoski, Kari; Magnusson, S Peter; Bojsen-Møller, Jens; Finni, Taija

    2014-07-15

    High-load eccentric exercises have been a key component in the conservative management of chronic Achilles tendinopathy. This study investigated the effects of a 12-wk progressive, home-based eccentric rehabilitation program on ankle plantar flexors' glucose uptake (GU) and myoelectric activity and Achilles tendon GU. A longitudinal study design with control (n = 10) and patient (n = 10) groups was used. Surface electromyography (SEMG) from four ankle plantar flexors and GU from the same muscles and the Achilles tendon were measured during submaximal intermittent isometric plantar flexion task. The results indicated that the symptomatic leg was weaker (P < 0.05) than the asymptomatic leg at baseline, but improved (P < 0.001) with eccentric rehabilitation. Additionally, the rehabilitation resulted in greater GU in both soleus (P < 0.01) and lateral gastrocnemius (P < 0.001) in the symptomatic leg, while the asymptomatic leg displayed higher uptake for medial gastrocnemius and flexor hallucis longus (P < 0.05). While both patient legs had higher tendon GU than the controls (P < 0.05), there was no rehabilitation effect on the tendon GU. Concerning SEMG, at baseline, soleus showed more relative activity in the symptomatic leg compared with both the asymptomatic and control legs (P < 0.05), probably reflecting an effort to compensate for the decreased force potential. The rehabilitation resulted in greater SEMG activity in the lateral gastrocnemius (P < 0.01) of the symptomatic leg with no other within- or between-group differences. Eccentric rehabilitation was effective in decreasing subjective severity of Achilles tendinopathy. It also resulted in redistribution of relative electrical activity, but not metabolic activity, within the triceps surae muscle. Copyright © 2014 the American Physiological Society.

  17. Treatment of osteoarthritis of the first carpometacarpal joint by resection-suspension-interposition arthoplasty using the split abductor pollicis longus tendon.

    PubMed

    Harenberg, P S; Jakubietz, M G; Jakubietz, R G; Schmidt, K; Meffert, R H

    2013-02-01

    Reduction of pain and gain of functionality in symptomatic osteoarthritis of the first carpometacarpal joint. Idiopathic, rheumatic, or posttraumatic osteoarthritis of the first carpometacarpal joint. RELATIVE CONTRAINDICATIONS: Poor general condition, poor condition of the hand's soft tissue/skin, chronic regional pain syndrome, current or recent infections of the hand, heavy manual labor (decision on a by-case basis). Supine position, hand pronated or slightly tilted. Upper arm tourniquet (Esmarch's method). Loupe magnification. Incision over the first extensor compartment. Exposure and incision of the thumb's basal joint. Resection of the trapezium. Exposure of the abductor pollicis longus (APL) tendon. Longitudinal split of the tendon harvesting the distally based ulnar part of the tendon. The split APL tendon is wrapped around the flexor carpi radialis (FCR) muscle tendon, suturing it to the tendon and back to itself. The rest of the split APL tendon is placed into the gap between the scaphoid and the first metacarpal bone, which is followed by wound closure. Plaster cast (thumb abduction splint) for 4 weeks. Stable commercially available wrist brace for at least 2 more weeks. There were no significant differences between the FCR arthroplasty (Epping's method) and the APL arthroplasty (Wulle's technique) regarding pain (visual analog scale), disability/usability (DASH score), or range of motion. Patients who had undergone APL arthroplasty showed significantly better grip and pinch strength. Furthermore, the operating time was significantly shorter and scars were significantly smaller in APL arthroplasty.

  18. Bilateral Posterior Tibial Tendon and Flexor Digitorum Longus Dislocations.

    PubMed

    Padegimas, Eric M; Beck, David M; Pedowitz, David I

    2017-04-01

    The authors present a case of a previously healthy and athletic 17-year-old female who presented with a 3.5-year history of medial left ankle pain after sustaining an inversion injury while playing basketball. Prior to presentation, she had failed prior immobilization and physical therapy for a presumed ankles sprain. Physical examination revealed a dislocated posterior tibial tendon (PTT) that was temporarily reducible, but would spontaneously dislocate immediately after reduction. She had pain and snapping of the PTT with resisted ankle plantar flexion and resisted inversion as well as 4/5 strength in ankle inversion. The diagnosis of dislocated PTT was confirmed on magnetic resonance imaging (MRI). The patient underwent suture anchor repair of the medial retinaculum of the left ankle. At the time of surgery both the PTT and flexor digitorum longus (FDL) were dislocated. Three months postoperatively, the patient represented with PTT dislocation of the right (nonoperative) ankle confirmed by MRI. After failure of immobilization, physical therapy, and oral anti-inflammatory medications, the patient underwent suture anchor repair of the medial retinaculum of the right ankle. At 6 months postoperatively, the patient has 5/5 strength inversion bilaterally, no subluxation of either PTT, and has returned to all activities without limitation. The authors present this unique case of bilateral PTT dislocation and concurrent PTT/FDL dislocation along with review of the literature for PTT dislocation. The authors highlight the common misdaiganosis of this injury and highlight the successful results of surgical intervention. Level V: Case report.

  19. Soft tissue stabilization for palmar midcarpal instability using a palmaris longus tendon graft.

    PubMed

    Chaudhry, Tahseen; Shahid, Mohammed; Wu, Feiran; Mishra, Anuj; Deshmukh, Subodh

    2015-01-01

    To report the results of a technique of soft tissue stabilization for palmar midcarpal instability using a palmaris longus graft. In patients' symptomatic wrists with palmar midcarpal instability that had failed conservative management, we used a dorsal approach and stabilized the hamate and triquetrum by reconstructing the dorsal triquetrohamate ligament. The palmaris longus tendon graft was fixed with bone anchors. Seven wrists in 6 patients were available for follow-up at a mean of 28 months (range, 17-37 mo). There was an overall meaningful improvement in function (mean preoperative Disabilities of the Arm, Shoulder, and Hand score, 49 preoperatively, 28 postoperatively). There was a significant increase in grip strength from 15 to 21 kg. At final follow-up, 2 patients had moderate pain. The others had mild or no pain. Four patients returned to their previous occupation or activity. Patients retained full pronation and supination. When compared with the normal side, flexion was reduced to 71%, extension to 81%, radial deviation to 90%, and ulnar deviation to 65% of the opposite side. Although the mean results show an improvement, one patient had a poor result with deterioration in Disabilities of the Arm, Shoulder, and Hand score in spite of a clinically stable wrist, and another had clinical evidence of recurrent instability during pregnancy. One patient had residual symptoms from a prominent bone anchor. Overall, this technique showed good medium-term results in most of our patients. It retained some midcarpal mobility, eliminated clunking in most patients, and provided a noteworthy improvement in grip strength and function. We continue to use this technique for patients with symptomatic midcarpal instability, but it requires further evaluation with larger patient numbers and a longer follow-up to assess its overall value. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  20. Multiple tendon ruptures of unknown etiology.

    PubMed

    Axibal, Derek P; Anderson, John G

    2013-10-01

    Tendon ruptures are common findings in foot and ankle practice. The etiology of tendon ruptures tends to be multifactorial-usually due to a combination of trauma, effects of systemic diseases, adverse effects of medications, and obesity. We present an unusual case of right Achilles tendinitis, left Achilles tendon rupture, bilateral peroneus longus tendon rupture, and left peroneus brevis tendon rupture of unknown etiology. This case report highlights the need for research for other possible, lesser known etiologies of tendon pathology. Therapeutic, Level IV, Case Study.

  1. [Neglected ipsilateral simultaneous ruptures of patellar and quadriceps tendon].

    PubMed

    Karahasanoğlu, İlker; Yoloğlu, Osman; Kerimoğlu, Servet; Turhan, Ahmet Uğur

    2015-01-01

    Neglected patellar and quadriceps tendon rupture is a rare injury, but ipsilateral simultaneous patellar and quadriceps tendon rupture was not described in the literature to our knowledge. In this article, we report a 40-year-old healthy male patient with neglected ipsilateral patellar and quadriceps tendon ruptures treated by peroneus longus tendon autograft. Patient had received some conservative and surgical treatments for patellar fracture before applying to our clinic. After our treatment using peroneus longus autograft and interference nails, patient was immobilized for six weeks in cylindrical cast. Flexion exercises and full weight bearing were started after cast removal. Patient had no complaint at postoperative second year. Patient was a neglected case. Surgical repair and early rehabilitation enabled us to achieve a satisfactory outcome.

  2. Isolated avulsion fracture of the first metatarsal base at the peroneus longus tendon attachment: a case report.

    PubMed

    Weinberg, Maxwell W; Krähenbühl, Nicola; Davidson, Nathan P; Hanrahan, Christopher J; Barg, Alexej

    2018-05-01

    Avulsion fractures of the first metatarsal (MT1) base at the peroneus longus (PL) tendon attachment are rare and may be undiagnosed during an emergency visit. If the injury is not treated properly, chronic pain or persistent impairment for inversion and plantar-flexion of the first ray may occur. This case report presents a 30-year-old woman who presented 10 weeks post trauma to a foot and ankle surgeon due to a swollen right midfoot with diffuse tenderness over the medial Lisfranc joint. Further evaluation showed an isolated avulsion fracture of the first metatarsal, which was undiagnosed during the emergent visit following the accident. In this case, the patient was successfully treated conservatively. The goal of this article is to raise awareness of this rare injury for radiologists and orthopedic surgeons.

  3. Effect of wrist and interphalangeal thumb movement on zone T2 flexor pollicis longus tendon tension in a human cadaver model.

    PubMed

    Rappaport, Patricia O; Thoreson, Andrew R; Yang, Tai-Hua; Reisdorf, Ramona L; Rappaport, Stephen M; An, Kai-Nan; Amadio, Peter C

    2015-01-01

    Therapy after flexor pollicis longus (FPL) repair typically mimics finger flexor management, but this ignores anatomic and biomechanical features unique to the FPL. We measured FPL tendon tension in zone T2 to identify biomechanically appropriate exercises for mobilizing the FPL. Eight human cadaver hands were studied to identify motions that generated enough force to achieve FPL movement without exceeding hypothetical suture strength. With the carpometacarpal and metacarpophalangeal joints blocked, appropriate forces were produced for both passive interphalangeal (IP) motion with 30° wrist extension and simulated active IP flexion from 0° to 35° with the wrist in the neutral position. This work provides a biomechanical basis for safely and effectively mobilizing the zone T2 FPL tendon. Our cadaver study suggests that it is safe and effective to perform early passive and active exercise to an isolated IP joint. NA. Copyright © 2015 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  4. [Upright posture of man and morphologic evolution of the musculi extensores digitorum pedis with reference to evolutionary myology. III].

    PubMed

    Kaneff, A

    1986-01-01

    The following anatomical objects were studied with regard to myology during evolution: M. extensor hallucis longus (MEHL), M. extensor digitorum longus (MEDL) with M. peroneus tertius (MP III), M. peroneus brevis (MPB) with M. peroneus digiti V (MPD V), M. extensor hallucis brevis (MEHB), M. extensor digitorum brevis (MEDB), and the Retinaculum musculorum extensorum imum (RMEI). The study was carried out by the preparation of 3 different groups of material. The 1st group consists of lower extremities of humans. The number of the extremities differs for the particular objects between 151 and 358 (see page 381). The 2nd group of material consists of 122 Membra pelvina from Marsupialia, Insectivora, and Primates. Table 1 shows as well the mammalian species as the number of the studied extremities. The extremities of the 1st and 2nd group were preserved in an manner suitable for a macroscopic preparation. The 3rd group of material consists of 71 lower extremities from embryos and fetus. The lower legs and feet were stained either according to the method described by Morel and Bassal with eosin added or according to Weigert. From this material, complete series of cross sections were prepared. Table 2 shows the age of the embryos (VCL [mm]) as well as the number of the studied extremities. It is important that up to the age of 46 mm VCL the difference in the age of the embryos usually amounts from 0.5 to 1.0 mm. This small difference in the age of the embryos and fetus allows a very good follow up of the changes in construction during the organogenesis. The comparison of the 3 different groups shows the following changes for the above mentioned muscles: The M. extensor hallucis longus (MEHL) is a muscle which is not split. The same result applies for its tendon which inserts at the distal phalanx of the hallux. This primitive form of the muscle amounts actually to 51.12% in human beings. In 48.88% of the cases, additional tendons and muscles are formed by the MEHL. Most

  5. Cuboid oedema due to peroneus longus tendinopathy: a report of four cases.

    PubMed

    O'Donnell, Paul; Saifuddin, Asif

    2005-07-01

    To highlight focal bone abnormality in the cuboid due to tendinopathy of the adjacent peroneus longus. A retrospective review was carried out of the relevant clinical and imaging features. Two male and two female patients were studied, mean age 51.5 years (range 32-67 years), referred with foot pain and imaging showing an abnormal cuboid thought to represent either tumour or infection. A long history of foot pain was usual with a maximum of 8 years. Radiographs were normal in two cases and showed erosion in two, one of which exhibited periosteal new bone formation affecting the cuboid. Bone scintigraphy was undertaken in two patients, both of whom showed increased uptake of isotope. MRI, performed in all patients, showed oedema in the cuboid adjacent to the peroneus longus tendon. The tendon and/or paratendinous tissues were abnormal in all cases, but no tendon discontinuity was identified. One patient possessed an os peroneum. Unequivocal evidence of bone erosion was seen using MRI in three patients, but with greater clarity in two cases using CT. Additional findings of tenosynovitis of tibialis posterior, oedema in the adjacent medial malleolus and synovitis of multiple joints in the foot were seen in one patient. Imaging diagnosis was made in all cases avoiding bone biopsy, but surgical exploration of the peroneal tendons was performed in two cases and biopsy of ankle synovium in one. Oedema with erosion of the cuboid bone, simulating a bone lesion (cuboid "pseudotumour"), may be caused by adjacent tendinopathy of peroneus longus. It is vital to be aware of this entity to avoid unnecessary biopsy of the cuboid.

  6. Results of Treatment of Posterior Ankle Impingement Syndrome and Flexor Hallucis Longus Tendinopathy in Dancers: A Systematic Review.

    PubMed

    Rietveld, A B M Boni; Hagemans, F M T; Haitjema, S; Vissers, T; Nelissen, R G H H

    2018-03-15

    Dancing on pointe and relevé requires extreme plantar flexion of the talo-crural joint. Hence, these positions may lead to posterior ankle impingement syndrome (PAIS). PAIS often coincides with flexor hallucis longus tendinopathy (FHL tendinopathy, or "dancers' tendinitis"). Both injuries can appear in isolation as well. The goal of this review is to evaluate the results and the available levels of evidence of conservative and operative treatment (both open and endoscopic) of PAIS and FHL tendinopathy in dancers. It also offers an insight into the history of dance medical publications on this subject. In October 2016, a systematic search of PubMed, Embase, Cochrane, CINAHL, Web of Science, and (in French) ScienceDirect databases was undertaken. Five hundred and seventy-six publications were found, of which a total of 27 reported the results of operative treatment in 376 ankles (344 open, 32 endoscopic) in 324 dancers. The outcome was good to excellent in most cases (89%). The mean period of return to dance for all surgeries combined (PAIS and FHL tendinopathy, open and endo) was 11 weeks (range: 4 to 36 weeks), and for isolated FHL tendinopathy 16 weeks (range: 8 to 36 weeks). Only six publications reported the results of conservative treatment in 33 ankles (13 PAIS, 20 FHL tendinopathy) of 28 dancers, which does not allow for any evidence-based recommendations. Most studies failed to include dance-specific baseline characteristics, like dance style and level of participation. We concluded that only retrospective studies with levels of evidence four and five show that operative treatment for PAIS and FHL tendinopathy is successful with few complications. Since isolated PAIS, PAIS combined with FHL tendinopathy, and isolated FHL injuries appear to be different pathological entities, more research taking into account demography, dance type, and level of participation is needed to find out in which cases early operative management should be considered or avoided. The

  7. Effects of Volar Tilt, Wrist Extension, and Plate Position on Contact Between Flexor Pollicis Longus Tendon and Volar Plate.

    PubMed

    Wurtzel, Caroline N Wolfe; Burns, Geoffrey T; Zhu, Andy F; Ozer, Kagan

    2017-12-01

    Volar plates positioned at, or distal to, the watershed line have been shown to have a higher incidence of attritional rupture of the flexor pollicis longus (FPL). In this study, we aimed to evaluate the effect of wrist extension and volar tilt on the contact between the plate and the FPL tendon in a cadaver model. We hypothesized that, following volar plate application, loss of native volar tilt increases the contact between the FPL and the plate at lower degrees of wrist extension. A volar locking plate was applied on 6 fresh-frozen cadavers. To determine the contact between the plate and the FPL tendon, both structures were wrapped with copper wire and circuit conductivity was monitored throughout wrist motion. A lateral wrist radiograph was obtained at each circuit closure, indicating tendon-plate contact. Baseline measurements were obtained with plate positioned at Soong grades 0, 1, and 2. An extra-articular osteotomy was made and contact was recorded at various volar tilt angles (+5°, 0°, -5°, -10°, -15°, and -20°) in 3 different plate positions. A blinded observer measured the degree of wrist extension on all lateral radiographs. Data were analyzed using linear mixed-effects regression model. Plates placed distal to the watershed line had the most contact throughout wrist range of motion. Significantly, less wrist extension was required for contact in wrists with neutral or dorsal tilt and in distally placed volar plates. Volar tilt, wrist extension, and plate position were 3 independent risk factors determining contact between plate and tendon. Loss of volar tilt, increased wrist extension, and higher Soong grade plate position result in greater contact between wire-wrapped FPL tendon and plate. The FPL/plate contact chart generated in this study may be used to assess the risk of rupture in the clinical setting. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  8. Abductor pollicis longus: a case of mistaken identity.

    PubMed

    Elliott, B G

    1992-08-01

    Abductor pollicis longus, long regarded as a motor for the thumb, is anatomically and functionally a radial deviator of the wrist and should be so named. The abductor carpi is proposed. If the other radial deviators of the wrist are acting this tendon can be selectively utilized as a transfer without loss of function. Reflex spasm of this muscle probably plays an important role in the radial deviation deformity seen in the rheumatoid hand.

  9. A rare cause of acute dysphagia: acute calcific tendonitis of the longus colli muscle.

    PubMed

    Abou Dargham, Hanadi; Bytyci, Faton; Shuman, Christian; Stolear, Anton

    2017-05-27

    We are presenting a case of a 78-year-old female with multiple comorbidities and history of neck surgery, who presented with acute dysphagia, odynophagia and neck pain that has been progressively getting worse over the course of 2 days, with no recent injury or infection. The patient was afebrile. There were no visible signs of infection on routine oropharyngeal examination. Initial workup was unremarkable except for elevated erythrocyte sedimentation rate, C-reactive protein and creatinine. CT of the cervical spine ruled out any fracture or cervical spine injury but showed an area of calcification, prevertebral oedema and fluid collection inferior to the anterior arch of C1. MRI of the cervical spine also showed prevertebral oedema and fluid collection in the retropharyngeal space from the skull base to the C3 level without abnormal surrounding enhancement that supported the diagnosis of acute calcific tendonitis of the longus colli muscle rather than an infectious process. There was significant improvement of symptoms 48 hours after initiating treatment with systemic steroids. The patient remains asymptomatic 6 months after treatment. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. Extensor tendon injury during cesarean delivery.

    PubMed

    Rinker, Brian

    2011-01-01

    Fetal laceration is a recognized complication of cesarean delivery; however, major injuries are rare. The case of a healthy newborn who sustained an injury to the extensor pollicis longus tendon during cesarean delivery is reported. The tendon was repaired surgically on the sixth day of life with good recovery of function. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  11. The influence of the Peroneus Longus muscle on the foot under axial loading: A CT evaluated dynamic cadaveric model study.

    PubMed

    Dullaert, K; Hagen, J; Klos, K; Gueorguiev, B; Lenz, M; Richards, R G; Simons, P

    2016-05-01

    Subtle hypermobility of the first tarsometatarsal joint can occur concomitantly with other pathologies and may be difficult to diagnose. Peroneus Longus muscle might influence stability of this joint. Collapse of the medial longitudinal arch is common in flatfoot deformity and the muscle might also play a role in correcting Meary's angle. A radiolucent frame was used to simulate weightbearing during CT examination. Eight pairs fresh-frozen lower legs were imaged in neutral position under non-weightbearing (75N), weightbearing (700N) and with 15kg weights hung from Peroneus Longus tendon. Measurements included first metatarsal rotation, intermetatarsal angle, first tarsometatarsal joint subluxation and Meary's angle. Weightbearing significantly increased Meary's angle and significantly decreased first tarsometatarsal joint subluxation (both P<0.01). Pulling Peroneus Longus tendon significantly increased first metatarsal rotation (P<0.01), significantly decreased the intermetatarsal angle (P<0.01) and increased non-significantly Meary's angle (P=0.52). A considerable effect weightbearing has on the medial longitudinal arch and first tarsometatarsal joint was observed. Pulling Peroneus Longus tendon improved first metatarsal subluxation but increased its rotation. The study calls into question the importance of this tendon in maintaining the medial longitudinal arch and raises concerns about rotational deformity of the first metatarsal following hallux valgus correction without first tarsometatarsal arthrodesis. Study outcomes will provide more insight in foot pathology. Weightbearing affects anatomy of the foot. No reliable information is available concerning the influence of the Peroneus muscle. This study investigates the influence of weightbearing and the impact the Peroneus muscle on the anatomy of the foot. Copyright © 2016. Published by Elsevier Ltd.

  12. Treatment of the neglected Achilles tendon rupture.

    PubMed

    Bevilacqua, Nicholas J

    2012-04-01

    Achilles tendon ruptures are best managed acutely. Neglected Achilles tendon ruptures are debilitating injuries and the increased complexity of the situation must be appreciated. Surgical management is recommended, and only in the poorest surgical candidate is conservative treatment entertained. Numerous treatment algorithms and surgical techniques have been described. A V-Y advancement flap and flexor halluces longus tendon transfer have been found to be reliable and achieve good clinical outcomes for defects ranging from 2 cm to 8 cm. This article focuses on the treatment options for the neglected Achilles tendon rupture. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Fibularis tertius: revisiting the anatomy.

    PubMed

    Rourke, K; Dafydd, H; Parkin, I G

    2007-11-01

    Fibularis tertius (FT) may be used during reconstructive surgery and muscle transposition with retention of function. The muscle was examined in both lower limbs of 41 cadavers. Measurements were made of muscle belly length and width, tendon length and width, and the size of the origin on the fibula. Tendon insertion, nerve and blood supplies were also examined. FT was absent in five (6.1%) lower limbs of three (7.3%) subjects. The size of its origin demonstrated inter- and intra-individual variation. FT arose from the distal fibula and on average occupied (28.4 +/- 9.1)% (mean +/- S. D.) of the total shaft length. In all cases the tendon inserted into the dorsal surface of the shafts of both the fourth and fifth metatarsals. A small nerve branch consistently arose from the deep fibular nerve near the origin of extensor digitorum longus. The nerve ran parallel to the length of this muscle, between it and extensor hallucis longus, before piercing FT. Anatomy textbooks describe FT as inserting into the fifth metatarsal only. This study, supported by data from previous reports, suggests that the "textbook" accounts of FT should be updated to record that most commonly its tendon reaches both the fourth and fifth metatarsals.

  14. Multiple variations of the tendons of the anatomical snuffbox.

    PubMed

    Thwin, San San; Fazlin, Fazlin; Than, Myo

    2014-01-01

    Multiple tendons of the abductor pollicis longus (APL) in the anatomical snuffbox of the wrist can lead to the development of de Quervain's syndrome, which is caused by stenosing tenosynovitis. A cadaveric study was performed to establish the variations present in the tendons of the anatomical snuffbox in a Malaysian population, in the hope that this knowledge would aid clinical investigation and surgical treatment of de Quervain's tenosynovitis. Routine dissection of ten upper limbs was performed to determine the variations in the tendons of the anatomical snuffbox of the wrist. In all the dissected upper limbs, the APL tendon of the first extensor compartment was found to have several (3-14) tendon slips. The insertion of the APL tendon slips in all upper limbs were at the base of the first metacarpal bone, trapezium and fascia of the opponens pollicis muscle; however, in seven specimens, they were also found to be attached to the fleshy belly of the abductor pollicis brevis muscle. In two specimens, double tendons of the extensor pollicis longus located in the third extensor compartment were inserted into the capsule of the proximal interphalangeal joints before being joined to the extensor expansion. In two other specimens, the first extensor compartment had two osseofibrous tunnels divided by a septum that separated the APL tendon from the extensor pollicis brevis tendon. Multiple variations were found in the anatomical snuffbox region of the dissected upper limbs. Knowledge of these variations would be useful in interventional radiology and orthopaedic surgery.

  15. Multiple variations of the tendons of the anatomical snuffbox

    PubMed Central

    Thwin, San San; Zaini, Fazlin; Than, Myo

    2014-01-01

    INTRODUCTION Multiple tendons of the abductor pollicis longus (APL) in the anatomical snuffbox of the wrist can lead to the development of de Quervain's syndrome, which is caused by stenosing tenosynovitis. A cadaveric study was performed to establish the variations present in the tendons of the anatomical snuffbox in a Malaysian population, in the hope that this knowledge would aid clinical investigation and surgical treatment of de Quervain's tenosynovitis. METHODS Routine dissection of ten upper limbs was performed to determine the variations in the tendons of the anatomical snuffbox of the wrist. RESULTS In all the dissected upper limbs, the APL tendon of the first extensor compartment was found to have several (3–14) tendon slips. The insertion of the APL tendon slips in all upper limbs were at the base of the first metacarpal bone, trapezium and fascia of the opponens pollicis muscle; however, in seven specimens, they were also found to be attached to the fleshy belly of the abductor pollicis brevis muscle. In two specimens, double tendons of the extensor pollicis longus located in the third extensor compartment were inserted into the capsule of the proximal interphalangeal joints before being joined to the extensor expansion. In two other specimens, the first extensor compartment had two osseofibrous tunnels divided by a septum that separated the APL tendon from the extensor pollicis brevis tendon. CONCLUSION Multiple variations were found in the anatomical snuffbox region of the dissected upper limbs. Knowledge of these variations would be useful in interventional radiology and orthopaedic surgery. PMID:24452976

  16. Late extensor pollicis longus rupture following plate fixation in Galeazzi fracture dislocation

    PubMed Central

    Sabat, Dhananjaya; Dabas, Vineet; Dhal, Anil

    2014-01-01

    Late rupture of extensor pollicis longus (EPL) tendon after Galeazzi fracture dislocation fixation is an unknown entity though it is a well-established complication following distal radius fractures. We report the case of a 55-year old male who presented with late EPL tendon rupture 4 months following internal fixation of Galeazzi fracture dislocation with a Locking Compression Plate (LCP). He was managed with extensor indicis proprius (EIP) transfer to restore thumb extension. At 4 years followup, functional result of the transfer was good. We identify possible pitfalls with this particular patient and discuss how to avoid them in future. PMID:25143650

  17. [A special soft tissue procedure for treatment of hallux valgus].

    PubMed

    Waizy, H; Stukenborg-Colsman, C; Abbara-Czardybon, M; Emmerich, J; Windhagen, H; Frank, D

    2011-02-01

    Maintaining the corrected position of the first metatasophalangeal axis. Reducing postoperative stiffness by forgoing a medial capsular shift. Hallux valgus deformities or recurrent hallux valgus deformities. Existing osteoarthritis, joint stiffness, large bone defects, osteonecrosis. General medical contraindications to surgical interventions and anesthesiological procedures. Operation under regional anesthesia (foot block) or general anesthesia. Tourniquet. Longitudinal skin incision medial over the pseudexostosis of the first metatarsal bone. Preparing the tendon of the Musculus abductor hallucis. Detaching the tendon from the capsule. Incision of the joint capsule with protection of the extensor hallucis longus tendon and the dorsal neurovascular bundle in an L-wise manner. Osteotomy of the first metatarsal bone. Lax sutures of the capsule in correct position and reattachment of the Musculus abductor hallucis tendon shifted toward distal and dorsal, regarding the rotation of the hallux. Postoperative elevation of the operated foot. Analgesia with nonsteroidal antiinflammatory drugs. Postoperative weight-bearing according to the osteotomy. Passive mobilization of the metatarsophalangeal joint. Dressing for 4 weeks postoperatively in the corrected position. Radiologic control after 6 weeks. Hallux valgus orthosis at night and a toe spreader for a further 6 weeks. A total of 30 isolated hallux valgus deformities with a mean preoperative intermetatarsal (IMA) angle of 12.9° (range 11-15°) were operated with a chevron osteotomy. The mean follow-up was 14.4 (range 8-17) months. The mean dorsiflexion at the last follow-up was 44° (range 20-60°). Only 2 patients had a dorsiflexion <40°. The mean reduction of the IM angle was 5.6° (range 3-7°). One patient required wound revision. There was no infection or avascular necrosis of the metatarsal head observed in the patients. At follow-up, 20 (67%) patients were completely satisfied, 9 (30%) satisfied, and 1 (3

  18. Hand Surgeon Reporting of Tendon Rupture Following Distal Radius Volar Plating

    PubMed Central

    Monaco, Nathan A.; Dwyer, C. Liam; Ferikes, Alex J.; Lubahn, John D.

    2016-01-01

    Background: Volar plate fixation with locked screws has become the preferred treatment of displaced distal radius fractures that cannot be managed nonoperatively. This treatment, however, is not without complication. The purpose of this study was to determine what percentage of hand surgeons, over a 12-month period, have experienced a tendon complication when using volar plates for the treatment of distal radius fractures. Methods: A total of 3022 hand surgeons were e-mailed a link to an online questionnaire regarding their observation and treatment of tendon injuries associated with volar plating of distal radius fractures. Responses were reported using descriptive statistics. Results: Of the 596 (20%) respondents, 199 (33%) surgeons reported encountering at least one flexor tendon injury after distal radius volar plating over the past year of practice. The flexor pollicis longus was the most commonly reported tendon injury (254, 75%). Palmaris longus grafting (118, 37%) and tendon transfer (114, 36%) were the most often reported treatments following this complication. A total of 216 respondents (36%) also encountered 324 cases of extensor tendon rupture after volar plating of distal radius fractures, with tendon transfer (88%) being the preferred treatment option. Conclusions: Both flexor and extensor tendon ruptures can be seen after volar plating of distal radius fractures. Surgeons should be aware of these complications. Critical assessment of hardware position at the time of index procedure is recommended to avoid complications. Long-term studies are needed to standardize approaches to managing tendon rupture following volar plating of distal radius fractures. PMID:27698628

  19. Hand Surgeon Reporting of Tendon Rupture Following Distal Radius Volar Plating.

    PubMed

    Monaco, Nathan A; Dwyer, C Liam; Ferikes, Alex J; Lubahn, John D

    2016-09-01

    Background: Volar plate fixation with locked screws has become the preferred treatment of displaced distal radius fractures that cannot be managed nonoperatively. This treatment, however, is not without complication. The purpose of this study was to determine what percentage of hand surgeons, over a 12-month period, have experienced a tendon complication when using volar plates for the treatment of distal radius fractures. Methods: A total of 3022 hand surgeons were e-mailed a link to an online questionnaire regarding their observation and treatment of tendon injuries associated with volar plating of distal radius fractures. Responses were reported using descriptive statistics. Results: Of the 596 (20%) respondents, 199 (33%) surgeons reported encountering at least one flexor tendon injury after distal radius volar plating over the past year of practice. The flexor pollicis longus was the most commonly reported tendon injury (254, 75%). Palmaris longus grafting (118, 37%) and tendon transfer (114, 36%) were the most often reported treatments following this complication. A total of 216 respondents (36%) also encountered 324 cases of extensor tendon rupture after volar plating of distal radius fractures, with tendon transfer (88%) being the preferred treatment option. Conclusions: Both flexor and extensor tendon ruptures can be seen after volar plating of distal radius fractures. Surgeons should be aware of these complications. Critical assessment of hardware position at the time of index procedure is recommended to avoid complications. Long-term studies are needed to standardize approaches to managing tendon rupture following volar plating of distal radius fractures.

  20. Positioning Techniques to Reduce the Occurrence of DeQuervain's Tendonitis in Nursing Mothers

    ERIC Educational Resources Information Center

    Virzi, Alison

    2010-01-01

    DeQuervain's tendonitis is an inflammation of two tendons: the extensor pollicis brevis and the abductor pollicis longus as they cross in the first dorsal compartment of the wrist. Symptoms include pain, swelling along the radial aspect of the wrist, and a decrease in thumb motion. A positive Finkelstein's test at examination is seen. Frequently…

  1. Reconstruction of large defects of the lips and commissure using a composite radial forearm palmaris longus free flap associated with a lengthening temporalis myoplasty.

    PubMed

    Martin, Thomas; Sury, Florent; Goga, Dominique; Parmentier, Jerome; Rozen, Adam; Laure, Boris

    2012-08-01

    We performed a single-stage operation to reconstruct a large defect of the lips and commissure using a composite radial forearm-palmaris longus free flap. To obtain cranial traction and a voluntary smile, independently from any jaw movement, traction was achieved by using a lengthening temporalis myoplasty. The tendon attached to the coronoid process was fixed to the palmaris longus tendon, recreating a new commissure and a "neo-modiolus." Physical therapy was started on the 21st postoperative day to facilitate progress from a "mandibular smile," to ideally a spontaneous and symmetric smile after 3 months of therapy. This procedure was able to obtain good oral continence and a good commissural movement during smile which has not previously been mentioned in the published literature.

  2. Investigating tendon mineralisation in the avian hindlimb: a model for tendon ageing, injury and disease

    PubMed Central

    Agabalyan, Natacha A; Evans, Darrell J R; Stanley, Rachael L

    2013-01-01

    Mineralisation of the tendon tissue has been described in various models of injury, ageing and disease. Often resulting in painful and debilitating conditions, the processes underlying this mechanism are poorly understood. To elucidate the progression from healthy tendon to mineralised tendon, an appropriate model is required. In this study, we describe the spontaneous and non-pathological ossification and calcification of tendons of the hindlimb of the domestic chicken (Gallus gallus domesticus). The appearance of the ossified avian tendon has been described previously, although there have been no studies investigating the developmental processes and underlying mechanisms leading to the ossified avian tendon. The tissue and cells from three tendons – the ossifying extensor and flexor digitorum longus tendons and the non-ossifying Achilles tendon – were analysed for markers of ageing and mineralisation using histology, immunohistochemistry, cytochemistry and molecular analysis. Histologically, the adult tissue showed a loss of healthy tendon crimp morphology as well as markers of calcium deposits and mineralisation. The tissue showed a lowered expression of collagens inherent to the tendon extracellular matrix and presented proteins expressed by bone. The cells from the ossified tendons showed a chondrogenic and osteogenic phenotype as well as tenogenic phenotype and expressed the same markers of ossification and calcification as the tissue. A molecular analysis of the gene expression of the cells confirmed these results. Tendon ossification within the ossified avian tendon seems to be the result of an endochondral process driven by its cells, although the roles of the different cell populations have yet to be elucidated. Understanding the role of the tenocyte within this tissue and the process behind tendon ossification may help us prevent or treat ossification that occurs in injured, ageing or diseased tendon. PMID:23826786

  3. Anatomical characteristics of the flexor digitorum accessorius longus muscle and their relevance to tarsal tunnel syndrome a systematic review.

    PubMed

    Deleu, Paul-André; Bevernage, Bernhard Devos; Birch, Ivan; Maldague, Pierre; Gombault, Vincent; Leemrijse, Thibaut

    2015-07-01

    Clinical and cadaver studies have reported that supernumerary muscles could be the etiology of a variety of pathologic disorders, such as posterior impingement syndrome, tarsal tunnel syndrome (TTS), and flexor hallucis longus tenosynovitis. We describe a unique variant of the flexor digitorum accessorius longus (FDAL) muscle as an apparent cause of TTS, functioning as an independent flexor of the second toe, which has not been described in the literature. In addition to this case report, a systematic review was performed of TTS caused by the FDAL muscle. A targeted search of PubMed, the Cochrane Library, the Cumulative Index to Nursing and Allied Health Literature, and Web of Science identified full-text papers that fulfilled the inclusion and exclusion criteria. Twenty-nine papers were identified for inclusion in the systematic review: 12 clinical papers of TTS caused by the FDAL muscle and 17 cadaver-based papers. Clinicians often do not include the FDAL muscle in the differential diagnosis of TTS. This literature review suggests that the FDAL is an important muscle in terms of its functional and clinical significance. Knowledge of this muscle, its anatomical location and variations, and its magnetic resonance imaging characteristics may help clinicians make an accurate differential diagnosis.

  4. All-Inside Single-Bundle Reconstruction of the Anterior Cruciate Ligament with the Anterior Half of the Peroneus Longus Tendon Compared to the Semitendinosus Tendon: A Two-Year Follow-Up Study.

    PubMed

    Bi, Mingguang; Zhao, Chen; Zhang, Shuijun; Yao, Bin; Hong, Zheping; Bi, Qing

    2018-02-08

    The anterior half of the peroneus longus tendon (AHPLT) has been reported to be acceptable for ligament reconstruction with respect to strength and safety. However, there is little information regarding the clinical outcomes after using the AHPLT compared with other autograft tendons. A prospective randomized controlled study was performed to compare the results of 62 cases of all-inside anatomical single-bundle anterior cruciate ligament (ACL) reconstruction using the AHPLT and 62 cases using semitendinosus graft with an average of 30.0 ± 3.6 months' follow-up. Tunnel placements of enrolled cases were measured on three-dimensional (3D) computed tomography (CT) and X-ray imaging. Knee stability was assessed using the anterior drawer test, pivot shift test, and KT-1000. The International Knee Documentation Committee (IKDC) 2000 subjective score was used to evaluate functional outcomes. The American Orthopedic Foot and Ankle Score (AOFAS) and the assessment of eversion muscle strength were performed to evaluate the function of the ankle donor site. Tunnel positions, which were confirmed with 3D CT, were in the anatomical positions. At the final follow-up, there were no significant differences between the semitendinosus group and the AHPLT group in the IKDC score (90.4 ± 7.1 vs. 89.3. ± 8.4), KT 1000 measurements (1.71 ± 0.57 vs. 1.85 ± 0.77), pivot shift test, and Visual Analogue Scale (VAS) (0.15 ± 0.36 vs. 0.10 ± 0.30). No obvious ankle site complications were found at 24 months. The average AOFAS score of the AHPLT group was comparable to that of the semitendinosus tendon group (99.1 ± 1.40 vs. 99.5 ± 1.21). There was no significant difference in clinical outcomes or knee stability between the semitendinosus group and the AHPLT group at the 2-year follow-up. An AHPLT autograft may be a good alternative for all-inside ACL reconstruction with respect to its strength, safety, and donor site morbidity. Thieme Medical

  5. Clinical recovery of two hip adductor longus ruptures: a case-report of a soccer player

    PubMed Central

    2013-01-01

    Background Non-operative treatment of acute hip adductor longus ruptures in athletes has been described in the literature. However, very limited information concerning the recovery of this type of injury exists. This case represented a unique possibility to study the recovery of two acute adductor longus ruptures, using novel, reliable and validated assessment methods. Case presentation A 22-year old male soccer player (Caucasian) sustained two subsequent acute adductor longus ruptures, one in each leg. The injuries occurred 10 months apart, and were treated non-surgically in both situations. He was evaluated using hip-strength assessments, self-report and ultrasonography until complete muscle-strength recovery of the hip adductors had occurred. The player was able to participate in a full soccer training session without experiencing pain 15 weeks after the first rupture, and 12 weeks after the second rupture. Full hip adductor muscle-strength recovery was obtained 52 weeks after the first rupture and 10 weeks after the second rupture. The adductor longus injuries, as verified by initial ultrasonography (10 days post-injury), showed evidence of a complete tendon rupture in both cases, with an almost identical imaging appearance. It was only at 6 and 10 weeks ultrasonographic follow-up that the first rupture was found to include a larger anatomical area than the second rupture. Conclusion From this case we can conclude that two apparently similar hip adductor longus ruptures, verified by initial ultrasonography (10 days post-injury), can have very different hip adductor strength recovery times. Assessment of adductor strength recovery may therefore in the future be a useful and important additional measure for determining when soccer players with hip adductor longus ruptures can return safely to play. PMID:23693119

  6. Aging Does Not Alter Tendon Mechanical Properties During Homeostasis, but does Impair Flexor Tendon Healing

    PubMed Central

    Ackerman, Jessica E.; Bah, Ibrahima; Jonason, Jennifer H.; Buckley, Mark R.; Loiselle, Alayna E.

    2017-01-01

    Aging is an important factor in disrupted homeostasis of many tissues. While an increased incidence of tendinopathy and tendon rupture are observed with aging, it is unclear whether this is due to progressive changes in tendon cell function and mechanics over time, or an impaired repair reaction from aged tendons in response to insult or injury. In the present study we examined changes in the mechanical properties of Flexor Digitorum Longus (FDL), Flexor Carpi Ulnaris (FCU), and tail fascicles in both male and female C57Bl/6 mice between 3-27 months of age to better understand the effects of sex and age on tendon homeostasis. No change in max load at failure was observed in any group over the course of aging, although there were significant decreases in toe and linear stiffness in female mice from 3-months to 15, and to 22-27-months. No changes in cell proliferation were observed with aging, although an observable decrease in cellularity occurred in 31-month old tendons. Given that aging did not dramatically alter tendon mechanical homeostasis we hypothesized that a disruption in tendon homeostasis, via acute injury would result in an impaired healing response. Significant decreases in max load, stiffness, and yield load were observed in repairs of 22-month old mice, relative to 4-month old mice. No changes in cell proliferation were observed between young and aged, however a dramatic loss of bridging collagen extracellular matrix was observed in aged repairs suggest that matrix production, but not cell proliferation leads to impaired tendon healing with aging. PMID:28419543

  7. Effect of Vibram FiveFingers Minimalist Shoes on the Abductor Hallucis Muscle.

    PubMed

    Campitelli, Nicholas A; Spencer, Scott A; Bernhard, Kaitlyn; Heard, Kristen; Kidon, Alan

    2016-09-02

    This study investigated the effect of Vibram FiveFingers Bikila minimalist shoes on intrinsic foot musculature. We hypothesized that a gradual transition into minimalist shoes will increase the thickness of the abductor hallucis muscle. Forty-one individuals were divided into four groups: control (traditional shod) (n = 9), restricted walking in Vibram FiveFingers (n = 11), running in Vibram FiveFingers (n = 10), and unlimited walking in Vibram FiveFingers (n = 11). At baseline, 12 weeks, and 24 weeks, the thickness of the abductor hallucis muscle was determined using ultrasound. Statistical analysis was performed to determine the significance of differences in muscle thickness at the three different time points. The mean thickness of the abductor hallucis muscle at 24 weeks was significantly greater than that at baseline for the restricted walking (P = .005) and running (P < .001) groups. In the unlimited walking group, the mean thickness of the muscle at 12 weeks was significantly greater than that at baseline (P < .05) but not at 24 weeks. There were no significant differences in muscle thickness among the three time points for the control group (P = .432). This study demonstrated that wearing Vibram FiveFinger Bikila footwear over a controlled period of time, an unlimited amount of time, as well as transitioning runners over a 6-month period of time using the 10% philosophy for increasing mileage, significantly increases intrinsic muscle thickness of the abductor hallucis. The abductor hallucis muscle aids in support of the medial longitudinal arch, and an increase in this muscle thickness may help reduce running-related injuries thought to arise from arch weakness.

  8. Biomechanical Cadaveric Evaluation of Partial Acute Peroneal Tendon Tears.

    PubMed

    Wagner, Emilio; Wagner, Pablo; Ortiz, Cristian; Radkievich, Ruben; Palma, Felipe; Guzmán-Venegas, Rodrigo

    2018-06-01

    No clear guideline or solid evidence exists for peroneal tendon tears to determine when to repair, resect, or perform a tenodesis on the damaged tendon. The objective of this study was to analyze the mechanical behavior of cadaveric peroneal tendons artificially damaged and tested in a cyclic and failure mode. The hypothesis was that no failure would be observed in the cyclic phase. Eight cadaveric long leg specimens were tested on a specially designed frame. A longitudinal full thickness tendon defect was created, 3 cm in length, behind the tip of the fibula, compromising 66% of the visible width of the peroneal tendons. Cyclic testing was initially performed between 50 and 200 N, followed by a load-to-failure test. Tendon elongation and load to rupture were measured. No tendon failed or lengthened during cyclic testing. The mean load to failure for peroneus brevis was 416 N (95% confidence interval, 351-481 N) and for the peroneus longus was 723 N (95% confidence interval, 578-868 N). All failures were at the level of the defect created. In a cadaveric model of peroneal tendon tears, 33% of remaining peroneal tendon could resist high tensile forces, above the physiologic threshold. Some peroneal tendon tears can be treated conservatively without risking spontaneous ruptures. When surgically treating a symptomatic peroneal tendon tear, increased efforts may be undertaken to repair tears previously considered irreparable.

  9. Ultrasound definition of tendon damage in patients with rheumatoid arthritis. Results of a OMERACT consensus-based ultrasound score focussing on the diagnostic reliability.

    PubMed

    Bruyn, George A W; Hanova, Petra; Iagnocco, Annamaria; d'Agostino, Maria-Antonietta; Möller, Ingrid; Terslev, Lene; Backhaus, Marina; Balint, Peter V; Filippucci, Emilio; Baudoin, Paul; van Vugt, Richard; Pineda, Carlos; Wakefield, Richard; Garrido, Jesus; Pecha, Ondrej; Naredo, Esperanza

    2014-11-01

    To develop the first ultrasound scoring system of tendon damage in rheumatoid arthritis (RA) and assess its intraobserver and interobserver reliability. We conducted a Delphi study on ultrasound-defined tendon damage and ultrasound scoring system of tendon damage in RA among 35 international rheumatologists with experience in musculoskeletal ultrasound. Twelve patients with RA were included and assessed twice by 12 rheumatologists-sonographers. Ultrasound examination for tendon damage in B mode of five wrist extensor compartments (extensor carpi radialis brevis and longus; extensor pollicis longus; extensor digitorum communis; extensor digiti minimi; extensor carpi ulnaris) and one ankle tendon (tibialis posterior) was performed blindly, independently and bilaterally in each patient. Intraobserver and interobserver reliability were calculated by κ coefficients. A three-grade semiquantitative scoring system was agreed for scoring tendon damage in B mode. The mean intraobserver reliability for tendon damage scoring was excellent (κ value 0.91). The mean interobserver reliability assessment showed good κ values (κ value 0.75). The most reliable were the extensor digiti minimi, the extensor carpi ulnaris, and the tibialis posterior tendons. An ultrasound reference image atlas of tenosynovitis and tendon damage was also developed. Ultrasound is a reproducible tool for evaluating tendon damage in RA. This study strongly supports a new reliable ultrasound scoring system for tendon damage. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  10. [Experimental study of tendon graft fixation in anterior cruciate ligament reconstruction with cortical press-fit bolt in rabbits].

    PubMed

    Qi, Wei; Li, Chun-bao; Wang, Jun-liang; Zhu, Juan-li; Liu, Yu-jie

    2013-05-21

    To explore the histological outcomes of tendon-bone healing in anterior cruciate ligament (ACL) reconstruction with cortical press-fit bolt (CPB). Twenty-four healthy female or male New Zealand White rabbits (2-3 months old) underwent bilateral ACL reconstruction with extensor digitorum longus tendon. A random method was used to decide one knee would receive the routine ACL reconstruction (control group) and another cortical press-fit bolt fixation (experimental group). After general anesthesia, extensor digitorum longus tendon was harvested and ACL reconstruction performed. All animals were sacrificed at 4, 8 and 12 weeks postoperation. Radiological and histological examinations were made at each timepoint. The specimens were stained with different methods to observe the pathological changes of tendon graft, bone tunnel and cortical press-fit bolt. More revascularization and massive new bone were found in tendon-bone junction of experimental group at 4, 8 and 12 weeks postoperation. The circum-graft new vessel proportion of the experimental and control groups were 0.48 ± 0.12 and 0.26 ± 0.05 respectively (P < 0.05). In the experimental group, more cartilage cells were present in tendon-bone junction at 12 weeks and the circum-graft new bone areas in two groups were 0.41 ± 0.11 and 0.21 ± 0.10 mm(2) respectively (P < 0.05). Cortical press-fit blot may improve tendon-bone healing after ACL reconstruction in rabbits. The application prospects of this procedure are promising.

  11. Atraumatic bilateral rupture of the peroneus brevis tendon in recreational sport: A case report

    PubMed Central

    Scheidegger, Patric; Weisskopf, Lukas; Hirschmüller, Anja

    2017-01-01

    Issue: Lower extremity tendon injuries often occur in physically active individuals. Most ruptures not involving great force are diagnosed in patients presenting underlying tendon degenerations. This also applies to patients taking medications because of a disease. We have observed several cases of bilateral Achilles tendon ruptures in patients who have been taking cortisone for a long period. We treated a healthy colleague (neurologist) in our clinic who sustained ruptures of the Achilles tendon on the left side (2012) and the peroneus brevis tendon on left side (2015) and right side (2016) after minimal traumata. Aim of this report is to provide a systematic review of this case and a literature review of similar cases, as few such cases have been published. Methods: We reviewed and analysed this patient’s records containing the sport-specific anamnesis, pre-existing condition, anamnesis of medications and therapy. The three injuries were magnetic resonance imaging–proven. Furthermore, the tendon’s condition was examined histologically in the context of the operative treatment through lace technique of the Achilles tendon and transfer of the peroneus brevis to the peroneus longus. We also researched the literature for bilateral ruptures of the peroneal tendons. Results and conclusion: The anamnesis confirmed no underlying disease. The patient took a macrolide antibiotic about half a year prior to the first peroneal injury for an otitis media. He denied having taken any other antibiotics, especially no quinolone antibiotics. However, the patient reported cortisone intake for 2 days some months before the second peroneal injury to treat an allergic reaction. That involved no local cortisone infiltration in the lower extremity. He underwent surgery within the first 2 weeks after each trauma. Each time, postoperative follow-ups revealed a good healing process. Three months after each operation, the patient was free of complaints. Axibal and Anderson described a

  12. Treatment of posterior tibial tendon dysfunction without flexor digitorum tendon transfer: a retrospective study of 34 patients.

    PubMed

    Didomenico, Lawrence; Stein, Dawn Y; Wargo-Dorsey, Mari

    2011-01-01

    A retrospective study of patients who underwent gastrocnemius recession, double calcaneal osteotomy (Evans osteotomy and percutaneous calcaneal displacement osteotomy), and medial column fusion for the treatment of posterior tibial tendon dysfunction was conducted. The senior author performed the procedures between November 2002 and January 2009 on 34 patients who displayed at least Johnson and Strom stage II deformity and had undergone 12 months of failed conservative treatment. The coauthors evaluated the patients' radiographs before and after the operation. At a mean of 14 (range 3 to 44) months after surgery, radiographic measurements demonstrated statistically significant changes in the structural alignment of the feet. Based on our experience with these patients, we believe that a double calcaneal osteotomy combined with a gastrocnemius recession and stabilization of the medial column for the treatment of posterior tibial tendon dysfunction provides satisfactory correction, stability, and realignment of the foot. Furthermore, we feel that the use of flexor digitorum longus transfer, as well as triple arthrodesis, can be avoided without compromising the outcome when surgically treating posterior tibial tendon dysfunction. Copyright © 2011 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Acute flexor tendon injury following midshaft radius and ulna fractures in a paediatric patient.

    PubMed

    Williams, James; Wharton, Rupert; Peev, Peter; Horwitz, Maxim

    2018-06-01

    Delayed rupture of the extensor and flexor tendons are recognised complications of distal radius fractures. However, acute flexor tendon rupture in the context of forearm fractures is rare. A twelve-year-old female sustained midshaft fractures of the radius and ulna. Intra-operatively the flexor pollicis longus (FPL) was found to be stripped from its musculotendinous junction at the level of the fracture fragment. The ruptured tendon was repaired using a modified Krackow technique at the time of fracture fixation. The repair was protected in plaster of Paris prior to referral to the paediatric hand clinic. The patient made a full recovery. Flexor tendon injury is a rare but potentially devastating consequence of acute forearm fractures. High energy trauma, significant volar angulation of the fracture fragment and clinical signs of flexor tendon injury should raise suspicion of this injury. A high index of suspicion in conjunction with repeat clinical examination of flexor tendon function should be performed before opting for closed management or intramedullary nailing in paediatric patients.

  14. Pitfalls during biomechanical testing - Evaluation of different fixation methods for measuring tendons endurance properties.

    PubMed

    Hangody, Gy; Pánics, G; Szebényi, G; Kiss, R; Hangody, L; Pap, K

    2016-03-01

    The goal of the study was to find a proper technique to fix tendon grafts into an INSTRON loading machine. From 8 human cadavers, 40 grafts were collected. We removed the bone-patella tendon-bone grafts, the semitendinosus and gracilis tendons, the quadriceps tendon-bone grafts, the Achilles tendons, and the peroneus longus tendons from each lower extremity. We tested the tendon grafts with five different types of fixation devices: surgical thread (Premicron 3), general mounting clamp, wire mesh, cement fixation, and a modified clamp for an INSTRON loading machine. The mean failure load in case of surgical thread fixation was (381N ± 26N). The results with the general clamp were (527N ± 45N). The wire meshes were more promising (750N ± 21N), but did not reach the outcomes we desired. Easy slippages of the ends of the tendons from the cement encasements were observed (253N ± 18N). We then began to use Shi's clamp that could produce 977N ± 416N peak force. We combined Shi's clamp with freezing of the graft and the rupture of the tendon itself demonstrated an average force of 2198 N ± 773N. We determined that our modified frozen clamp fixed the specimens against high tensile forces.

  15. High-resolution US and MR imaging of peroneal tendon injuries.

    PubMed

    Taljanovic, Mihra S; Alcala, Jennifer N; Gimber, Lana H; Rieke, Joshua D; Chilvers, Margaret M; Latt, L Daniel

    2015-01-01

    Injuries of the peroneal tendon complex are common and should be considered in every patient who presents with chronic lateral ankle pain. These injuries occur as a result of trauma (including ankle sprains), in tendons with preexisting tendonopathy, and with repetitive microtrauma due to instability. The peroneus brevis and peroneus longus tendons are rarely torn simultaneously. Several anatomic variants, including a flat or convex fibular retromalleolar groove, hypertrophy of the peroneal tubercle at the lateral aspect of the calcaneus, an accessory peroneus quartus muscle, a low-lying peroneus brevis muscle belly, and an os peroneum, may predispose to peroneal tendon injuries. High-resolution 1.5-T and 3-T magnetic resonance (MR) imaging with use of dedicated extremity coils and high-resolution ultrasonography (US) with high-frequency linear transducers and dynamic imaging are proved to adequately depict the peroneal tendons for evaluation and can aid the orthopedic surgeon in injury management. An understanding of current treatment approaches for partial- and full-thickness peroneal tendon tears, subluxation and dislocation of these tendons with superior peroneal retinaculum (SPR) injuries, intrasheath subluxations, and peroneal tendonopathy and tenosynovitis can help physicians achieve a favorable outcome. Patients with low functional demands do well with conservative treatment, while those with high functional demands may benefit from surgery if nonsurgical treatment is unsuccessful. Radiologists should recognize the normal anatomy and specific pathologic conditions of the peroneal tendons at US and MR imaging and understand the various treatment options for peroneal tendon and SPR superior peroneal retinaculum injuries. Online supplemental material is available for this article. RSNA, 2015

  16. Soleus Atrophy Is Common After the Nonsurgical Treatment of Acute Achilles Tendon Ruptures: A Randomized Clinical Trial Comparing Surgical and Nonsurgical Functional Treatments.

    PubMed

    Heikkinen, Juuso; Lantto, Iikka; Flinkkila, Tapio; Ohtonen, Pasi; Niinimaki, Jaakko; Siira, Pertti; Laine, Vesa; Leppilahti, Juhana

    2017-05-01

    It remains controversial whether nonsurgical or surgical treatment provides better calf muscle strength recovery after an acute Achilles tendon rupture (ATR). Recent evidence has suggested that surgery might surpass nonsurgical treatment in restoring strength after an ATR. To assess whether magnetic resonance imaging (MRI) findings could explain calf muscle strength deficits and the difference between nonsurgical and surgical treatments in restoring calf muscle strength. Randomized controlled trial; Level of evidence, 1. From 2009 to 2013, 60 patients with acute ATRs were randomized to surgery or nonsurgical treatment with an identical rehabilitation protocol. The primary outcome measure was the volume of calf muscles assessed using MRI at 3 and 18 months. The secondary outcome measures included fatty degeneration of the calf muscles and length of the affected Achilles tendon. Additionally, isokinetic plantarflexion strength was measured in both legs. At 3 months, the study groups showed no differences in muscle volumes or fatty degeneration. However, at 18 months, the mean differences between affected and healthy soleus muscle volumes were 83.2 cm 3 (17.7%) after surgery and 115.5 cm 3 (24.8%) after nonsurgical treatment (difference between means, 33.1 cm 3 ; 95% CI, 1.3-65.0; P = .042). The study groups were not substantially different in the volumes or fatty degeneration of other muscles. From 3 to 18 months, compensatory hypertrophy was detected in the flexor hallucis longus (FHL) and deep flexors in both groups. In the nonsurgical treatment group, the mean difference between affected and healthy FHL muscle volumes was -9.3 cm 3 (12%) and in the surgical treatment group was -8.4 cm 3 (10%) ( P ≤ .001). At 18 months, Achilles tendons were, on average, 19 mm longer in patients treated nonsurgically compared with patients treated surgically ( P < .001). At 18 months, surgically treated patients demonstrated 10% to 18% greater strength results ( P = .037). Calf

  17. Discharge properties of abductor hallucis before, during, and after an isometric fatigue task.

    PubMed

    Kelly, Luke A; Racinais, Sebastien; Cresswell, Andrew G

    2013-08-01

    Abductor hallucis is the largest muscle in the arch of the human foot and comprises few motor units relative to its physiological cross-sectional area. It has been described as a postural muscle, aiding in the stabilization of the longitudinal arch during stance and gait. The purpose of this study was to describe the discharge properties of abductor hallucis motor units during ramp and hold isometric contractions, as well as its discharge characteristics during fatigue. Intramuscular electromyographic recordings from abductor hallucis were made in 5 subjects; from those recordings, 42 single motor units were decomposed. Data were recorded during isometric ramp contractions at 60% maximum voluntary contraction (MVC), performed before and after a submaximal isometric contraction to failure (mean force 41.3 ± 15.3% MVC, mean duration 233 ± 116 s). Motor unit recruitment thresholds ranged from 10.3 to 54.2% MVC. No significant difference was observed between recruitment and derecruitment thresholds or their respective discharge rates for both the initial and postfatigue ramp contractions (all P > 0.25). Recruitment threshold was positively correlated with recruitment discharge rate (r = 0.47, P < 0.03). All motor units attained similar peak discharge rates (14.0 ± 0.25 pulses/s) and were not correlated with recruitment threshold. Thirteen motor units could be followed during the isometric fatigue task, with a decline in discharge rate and increase in discharge rate variability occurring in the final 25% of the task (both P < 0.05). We have shown that abductor hallucis motor units discharge relatively slowly and are considerably resistant to fatigue. These characteristics may be effective for generating and sustaining the substantial level of force that is required to stabilize the longitudinal arch during weight bearing.

  18. The effects of gluteus maximus and abductor hallucis strengthening exercises for four weeks on navicular drop and lower extremity muscle activity during gait with flatfoot.

    PubMed

    Goo, Young-Mi; Kim, Tae-Ho; Lim, Jin-Yong

    2016-03-01

    [Purpose] The purpose of the present study is to examine the effects of abductor hallucis and gluteus maximus strengthening exercises on pronated feet. [Subjects and Methods] The present study was conducted with 18 adults without no history of surgery on the foot or ankle. One group performed both gluteus maximus strengthening exercises and abductor hallucis strengthening exercises, while the other group performed only abductor hallucis strengthening exercises five times per week for four weeks. [Results] The group that performed both gluteus maximus and abductor hallucis strengthening exercises showed smaller values in the height of navicular drop than the group that performed only abductor hallucis strengthening exercises. The muscle activity of the gluteus maximus and the vastus medialis increased during heel-strike in the group that added gluteus maximus exercises, and the muscle activity of the abductor hallucis significantly increased in both groups. [Conclusion] Given the results of the present study, it can be suggested that strengthening the gluteus maximus while also performing exercises to correct the pronated foot is an effective method for achieving normal gait.

  19. Measuring tendon properties in mdx mice: cell viability and viscoelastic characteristics.

    PubMed

    Rizzuto, E; Musarò, A; Catizone, A; Del Prete, Z

    2009-10-16

    Muscular dystrophy is a genetic disorder of skeletal muscle characterized by progressive muscle weakness. Here we assessed whether muscle wasting affects cell viability and mechanical properties of extensor digitorum longus (EDL) and of tibialis anterior (TA) tendons from mdx dystrophic mice compared to wild type (WT) mice. mdx mice represent the classical animal model for human Duchenne muscular dystrophy, and show several signs of the pathology, including a decrease in specific force and an increase of fibrotic index. Cell viability of tendons was evaluated by histological analysis, and viscoelastic properties have been assessed by a rapid measurement protocol that allowed us to compute, at the same time, tissue complex compliance for all the frequencies of interest. Confocal microscopy and mechanical properties measurements revealed that mdx tendons, compared to WT ones, have an increase in the number of dead cells and a significant reduction in tissue elasticity for all the frequencies that were tested. These findings indicate a reduced quality of the tissue. Moreover, mdx tendons have an increase in the viscous response, indicating that during dynamic loading, they dissipate more energy compared to WT. Our results demonstrate that muscular dystrophy involves not only muscle wasting, but also alteration in the viscoelastic properties of tendons, suggesting a paracrine effect of altered skeletal muscle on tendinous tissue.

  20. Autologous tenocyte implantation into shoulder tendon pathology in an elite swimmer.

    PubMed

    Schwab, Laura M; Blanch, Peter; Young, Mark

    2018-01-01

    The use of novel bioengineer treatment techniques such as Autologous Tenocyte Implantation (ATI) have shown promising improvements in both pain ratings and functional outcomes in elbow, gluteal and shoulder tendon pathology. This case will review the injury timeline of ATI intervention in an elite male swimmer with subscapularis tendon pathology and investigate whether ATI has a concomitant healing effect associated with improved functional outcomes. A palmaris longus tendon biopsy was performed and cells were expanded by in-vitro culture. Autologous tenocytes were injected into the subscapularis site identified. Three blinded radiologists reported on pre and post shoulder MRIs using the same 3T MRI protocol. A validated rating scale for severity of tendinopathy (0-3) and degree of tear (0-3) was used and hand-held Dynamometry (HHD) strength was recorded. Independent blinded radiology review demonstrated a significant reduction in tear size and improved tendon morphology. IR strength on HHD returned to baseline strength levels post ATI (231-253N) 6 weeks post intervention. The athlete returned to full training (volume and intensity) pain free and international level competition at 4 months post ATI. An athlete who had previously undergone unsuccessful conservative management demonstrated significant improvement in function and in tendon morphology post intervention. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. A Biomechanical Comparison of Allograft Tendons for Ligament Reconstruction.

    PubMed

    Palmer, Jeremiah E; Russell, Joseph P; Grieshober, Jason; Iacangelo, Abigail; Ellison, Benjamin A; Lease, T Dylan; Kim, Hyunchul; Henn, R Frank; Hsieh, Adam H

    2017-03-01

    Allograft tendons are frequently used for ligament reconstruction about the knee, but they entail availability and cost challenges. The identification of other tissues that demonstrate equivalent performance to preferred tendons would improve limitations. Hypothesis/Purpose: We compared the biomechanical properties of 4 soft tissue allograft tendons: tibialis anterior (TA), tibialis posterior (TP), peroneus longus (PL), and semitendinosus (ST). We hypothesized that allograft properties would be similar when standardized by the looped diameter. Controlled laboratory study. This study consisted of 2 arms evaluating large and small looped-diameter grafts: experiment A consisted of TA, TP, and PL tendons (n = 47 each) with larger looped diameters of 9.0 to 9.5 mm, and experiment B consisted of TA, TP, PL, and ST tendons (n = 53 each) with smaller looped diameters of 7.0 to 7.5 mm. Each specimen underwent mechanical testing to measure the modulus of elasticity (E), ultimate tensile force (UTF), maximal elongation at failure, ultimate tensile stress (UTS), and ultimate tensile strain (UTε). Experiment A: No significant differences were noted among tendons for UTF, maximal elongation at failure, and UTϵ. UTS was significantly higher for the PL (54 MPa) compared with the TA (44 MPa) and TP (43 MPa) tendons. E was significantly higher for the PL (501 MPa) compared with the TP (416 MPa) tendons. Equivalence testing showed that the TP and PL tendon properties were equivalent or superior to those of the TA tendons for all outcomes. Experiment B: All groups exhibited a similar E. UTF was again highest in the PL tendons (2294 N) but was significantly different from only the ST tendons (1915 N). UTϵ was significantly higher for the ST (0.22) compared with the TA (0.19) and TP (0.19) tendons. Equivalence testing showed that the TA, TP, and PL tendon properties were equivalent or superior to those of the ST tendons. Compared with TA tendons, TP and PL tendons of a given looped

  2. The functional anatomy of Kager's fat pad in relation to retrocalcaneal problems and other hindfoot disorders.

    PubMed

    Theobald, P; Bydder, G; Dent, C; Nokes, L; Pugh, N; Benjamin, M

    2006-01-01

    Kager's fat pad is a mass of adipose tissue occupying Kager's triangle. By means of a combined magnetic resonance imaging, ultrasound, gross anatomical and histological study, we show that it has three regions that are closely related to the sides of the triangle. Thus, it has parts related to the Achilles and flexor hallucis longus (FHL) tendons and a wedge of fat adjacent to the calcaneus. The calcaneal wedge moves into the bursa during plantarflexion, as a consequence of both an upward displacement of the calcaneus relative to the wedge and a downward displacement of the wedge relative to the calcaneus. During dorsiflexion, the bursal wedge is retracted. The movements are promoted by the tapering shape of the bursal wedge and by its deep synovial infolds. Fibrous connections linking the fat to the Achilles tendon anchor and stabilize it proximally and thus contribute to the motility of its tip. We conclude that the three regions of Kager's fat pad have specialized functions: an FHL part which contributes to moving the bursal wedge during plantarflexion, an Achilles part which protects blood vessels entering this tendon, and a bursal wedge which we suggest minimizes pressure changes in the bursa. All three regions contribute to reducing the risk of tendon kinking and each may be implicated in heel pain syndromes.

  3. Extensor indicis proprius tendon transfer using shear wave elastography.

    PubMed

    Lamouille, J; Müller, C; Aubry, S; Bensamoun, S; Raffoul, W; Durand, S

    2017-06-01

    The means for judging optimal tension during tendon transfers are approximate and not very quantifiable. The purpose of this study was to demonstrate the feasibility of quantitatively assessing muscular mechanical properties intraoperatively using ultrasound elastography (shear wave elastography [SWE]) during extensor indicis proprius (EIP) transfer. We report two cases of EIP transfer for post-traumatic rupture of the extensor pollicis longus muscle. Ultrasound acquisitions measured the elasticity modulus of the EIP muscle at different stages: rest, active extension, active extension against resistance, EIP section, distal passive traction of the tendon, after tendon transfer at rest and then during active extension. A preliminary analysis was conducted of the distribution of values for this modulus at the various transfer steps. Different shear wave velocity and elasticity modulus values were observed at the various transfer steps. The tension applied during the transfer seemed close to the resting tension if a traditional protocol were followed. The elasticity modulus varied by a factor of 37 between the active extension against resistance step (565.1 kPa) and after the tendon section (15.3 kPa). The elasticity modulus values were distributed in the same way for each patient. The therapeutic benefit of SWE elastography was studied for the first time in tendon transfers. Quantitative data on the elasticity modulus during this test may make it an effective means of improving intraoperative adjustments. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

  4. The influence of freezing on the tensile strength of tendon grafts : a biomechanical study.

    PubMed

    Arnout, Nele; Myncke, Jan; Vanlauwe, Johan; Labey, Luc; Lismont, Daniel; Bellemans, Johan

    2013-08-01

    We investigated the influence of freezing on the tensile strength of fresh frozen tendon grafts. The biomechanical characteristics of tendons that are less commonly used in knee surgery (tibialis anterior, tibialis posterior, peroneus longus and medial and lateral half of Achilles tendons) were compared to those of a semitendinosus and gracilis graft harvested from the same 10 multi-organ donors. All right side tendons constituted the study group and were frozen at -80 degrees C and thawed at room temperature 5 times. All left side tendons were frozen at -80 degrees C and thawed at room temperature once. There were 59 tendons in the control group and 56 in the study group. The looped grafts were clamped at one side using a custom-made freeze clamp and loaded until failure on an Instron 4505 testing machine. The average ultimate failure load was not significantly different between the control and the study group (p > 0.05). The failure load of the medial tendon Achilles was the lowest in both study and control group (p < 0.001). There was no significant difference in maximum stress, maximum displacement, maximum strain and stiffness between the control and study group (p > 0.05). From our study, we conclude that freezing tendons at -80 degrees C and thawing several times does not influence the maximum load, maximum stress, maximum displacement, maximum strain and stiffness. The medial half of the Achilles tendon is clearly the weakest tendon (p < 0.001). These findings show that tendon grafts can be frozen at -80 degrees C and thawed at room temperature several times without altering their biomechanical properties.

  5. The location of the peroneus longus tendon in the cuboid groove: sonographic study in various positions of the ankle-foot in asymptomatic volunteers.

    PubMed

    Choo, Hye Jung; Lee, Sun Joo; Huang, Brady K; Resnick, Donald L

    2018-04-10

    To evaluate the normal location of the peroneus longus tendon (PL) in the cuboid groove in various ankle-foot positions by ultrasonography in asymptomatic volunteers. Ultrasonographic assessment of the PL in the cuboid groove was performed in 20 feet of ten healthy volunteers. Each PL was examined in five ankle-foot positions (i.e., neutral, dorsiflexion, plantar-flexion, supination, and pronation). The PL location was qualitatively categorized as "inside" when the PL was entirely within the cuboid groove, as "overlying" when some part of the PL was perched on the cuboid tuberosity, and as "outside" when the PL was entirely on the cuboid tuberosity. For quantitative evaluation of the PL location, the distance between the PL and the cuboid groove was measured. The width of the cuboid groove was measured in the neutral position. The PL location did not significantly change with changes in the ankle-foot position. Qualitatively, an "overlying" PL was the most common type, regardless of the ankle-foot position. "Inside" PLs were found in only 35, 20, 30, 25, and 35% of feet in neutral, dorsiflexion, plantar-flexion, supination, and pronation positions, respectively. The quantitative PL location was also not significantly different among all ankle-foot positions and it was significantly negatively correlated with the cuboid groove width. In healthy volunteers, 65% or more of the PLs were partially or completely located outside of the cuboid groove, regardless of the ankle-foot position. The PL location relative to the cuboid groove was related to the cuboid groove width.

  6. IS THERE ANY ROOM FOR TENDOSCOPY IN THE SURGICAL TREATMENT OF POSTERIOR TIBIAL TENDON INSUFFICIENCY?

    PubMed

    Bojanić, Ivan; Dimnjaković, Damjan; Mahnik, Alan; Smoljanović, Tomislav

    2016-05-01

    Posterior tibial tendon insufficiency (PTTI) is nowadays considered to be the main cause of adult-acquired flatfoot deformity (AAFD). The purpose of this study is to report the outcomes of tendoscopic treatment of tibialis poste- rior tendon (TP) in eleven patients with stage 1 or 2 PTTI and failed prior conservative treatment. Tendoscopy was carried out as a solitary procedure in 8 patients, while in 3 patients additional procedures such as ,,mini-open" tubularization of TP or anterior ankle arthroscopy were necessary. In a single patient transfer of flexor digitorum longus tendon was performed as a second stage surgery due to complete rupture of TP. Related with tendoscopic procedure, no complications were re- ported. TP tendoscopy is a useful and beneficial minimally invasive procedure to treat TP pathology at earlier stages of PTTI. It is a technically demanding procedure that requires extensive experience in arthroscopic management of small ioints and excellent knowledge of repional anatomy.

  7. Acute Tears of the Tibialis Posterior Tendon Following Ankle Sprain.

    PubMed

    Jackson, Lyle T; Dunaway, Linda J; Lundeen, Gregory A

    2017-07-01

    Traumatic tears of the tibialis posterior (TP) tendon following an ankle sprain are rare. The purpose of this study was to report our case series of TP tendon tears following an ankle sprain. Patients with persistent TP tendon pain after an ankle sprain were retrospectively identified over a 4-year period and reviewed. A comparison of magnetic resonance imaging (MRI) interpretations by a radiologist and surgeon was made. Patients failing conservative management underwent operative repair of the TP tendon tear and concomitant pathology. Failure of the index surgery was defined as TP tendinosis, which was treated with excision and flexor digitorum longus tendon transfer. Outcomes were measured with the Foot Function Index (FFI) and American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot scores. Thirteen patients were found to have a TP tendon tear following an ankle sprain. The incidence for TP tears with sprains presented to our clinic was 1.04%. MRI identified TP tendon pathology in 4 patients by a radiologist review and in 11 patients by a surgeon review. The most common concomitant pathology was a talar osteochondral defect in 13 of 13 patients and ligament instability in 12 of 13 patients (5/13 lateral, 3/13 medial, 4/13 multidirectional instability). Four of 13 patients failed the index surgery. Of the 9 remaining patients, 4 had clinical follow-up at an average of 4.6 years postoperatively. The average FFI subscale scores were the following: pain, 40.4; disability, 28.9; and activity, 23.6. The average AOFAS hindfoot score was 68.8. Despite being rare, a TP tendon tear should be included in the differential diagnosis for persistent medial-sided pain following an ankle sprain. MRI findings can be subtle. Associated pathology was very common and likely confounded the diagnosis and outcomes. Patients should be counseled on the possibility of poor outcomes and long-term pain. Level IV, case series.

  8. Cadaver study of anatomic landmark identification for placing ankle arthroscopy portals.

    PubMed

    Scheibling, B; Koch, G; Clavert, P

    2017-05-01

    Arthroscopy-assisted surgery is now widely used at the ankle for osteochondral lesions of the talus, anterior and posterior impingement syndromes, talocrural or subtalar fusion, foreign body removal, and ankle instability. Injuries to the vessels and nerves may occur during these procedures. To determine whether ultrasound topographic identification of vulnerable structures decreased the risk of iatrogenic injuries to vessels, nerves, and tendons and influenced the distance separating vulnerable structures from the arthroscope introduced through four different portals. Ultrasonography to identify vulnerable structures before or during arthroscopic surgery on the ankle may be useful. Twenty fresh cadaver ankles from body donations to the anatomy institute in Strasbourg, France, were divided into two equal groups. Preoperative ultrasonography to mark the trajectories of vessels, nerves, and tendons was performed in one group but not in the other. The portals were created using a 4-mm trocar. Each portal was then dissected. The primary evaluation criterion was the presence or absence of injuries to vessels, nerves, and tendons. The secondary evaluation criterion was the distance between these structures and the arthroscope. No tendon injuries occurred with ultrasonography. Without ultrasonography, there were two full-thickness tendon lesions, one to the extensor hallucis longus and the other to the Achilles tendon. Furthermore, with the anterolateral, anteromedial, and posteromedial portals, the distance separating the vessels and nerves from the arthroscope was greater with than without ultrasonography (P=0.041, P=0.005, and P=0.002), respectively; no significant difference was found with the anterior portal. Preoperative ultrasound topographic identification decreases the risk of iatrogenic injury to the vessels, nerves, and tendons during ankle arthroscopy and places these structures at a safer distance from the arthroscope. Our hypothesis was confirmed. IV

  9. Fixation of the Achilles tendon insertion using suture button technology.

    PubMed

    Fanter, Nathan J; Davis, Edward W; Baker, Champ L

    2012-09-01

    In the operative treatment of Achilles insertional tendinopathy, no guidelines exist concerning which form of fixation of the Achilles tendon insertion is superior. Transcalcaneal drill pin passage does not place any major plantar structures at risk, and the addition of a Krackow stitch and suture button to the fixation technique provides a significant increase in ultimate load to failure in Achilles tendon insertional repairs. Controlled laboratory study. The Achilles tendon insertions in 6 fresh-frozen cadaveric ankles were detached, and transcalcaneal drill pins were passed. Plantar dissection took place to evaluate the drill pin relationship to the plantar fascia, lateral plantar nerve and artery, flexor digitorum longus tendon, and master knot of Henry. The Achilles tendons were then repaired with a double-row suture anchor construct alone or with a suture button and Krackow stitch added to the double-row suture anchor construct. The repairs were then tested to maximum load to failure at 20 mm/min. The mode of failure was recorded, and the mean maximum load to failure was assessed using the Student t test for distributions with equal variance. Transcalcaneal drill pin passage did not place any selected anatomic structures at risk. The mean maximum load to failure for the suture bridge group was 239.2 N; it was 391.4 N for the group with the suture button (P = .014). The lateral plantar artery was the structure placed at greatest risk from drill pin placement, with a mean distance of 22.7 mm (range, 16.5-29.2 mm) between the pin and artery. In this laboratory study, transcalcaneal drill pin passage appeared to be anatomically safe, and the use of suture button technology with a Krackow stitch for Achilles tendon insertional repair significantly increased repair strength. Achilles tendon insertional repair with suture button fixation and a Krackow stitch may facilitate the earlier institution of postoperative rehabilitation and improve clinical outcomes.

  10. Extensor Pollicis Longus Injury in Addition to De Quervain’s with Text Messaging on Mobile Phones

    PubMed Central

    Kumar, Bhaskaranand; Bhat, Anil K; Venugopal, Anand

    2014-01-01

    Objective: To do a clinical and ultrasonic evaluation of subjects with thumb pain with text messaging. Background: Thumbs are commonly used for text messaging, which are not as well designed for fine manipulative or dexterous work. Repetitive use as in text messaging can lead to the injury to the tendons of the thumb. Materials and Methods: Ninety eight students with symptoms of Repetitive Strain Type of injuries of the thumb were selected from a survey and evaluated both clinically and by ultrasound analysis of the musculotendinous unit of the thumb to note changes due to excessive use of the mobile phone. Age and sex matched controls were also subjected to ultrasound evaluation. Results: Clinical examination showed positive Finkelstein test in 40% of the cases, significant reduction in the lateral and tip pinch strengths in the cases. Ultrasound detected changes in the first and the third compartments in 19% of the cases. Conclusion: Isolated cases of pain in the thumb have been reported but this study noted changes both clinically and by ultrasound in the tendons of the thumb. These changes should be taken as warning signs of possible subclinical changes taking place in the soft tissues of the thumb in these subjects due to repetitive use of mobile phones and thus, making them prone for developing painful Musculoskeletal Disorders. Application: Repetitive use of mobile phones for text messaging can lead to the damage of Extensor pollicis longus of the thumb in addition to the tendons of the first compartment of the wrist. PMID:25584249

  11. Ultrasound evaluation of foot muscles and plantar fascia in pes planus.

    PubMed

    Angin, Salih; Crofts, Gillian; Mickle, Karen J; Nester, Christopher J

    2014-01-01

    Multiple intrinsic and extrinsic soft tissue structures that apply forces and support the medial longitudinal arch have been implicated in pes planus. These structures have common functions but their interaction in pes planus is not fully understood. The aim of this study was to compare the cross-sectional area (CSA) and thickness of the intrinsic and extrinsic foot muscles and plantar fascia thickness between normal and pes planus feet. Forty-nine adults with a normal foot posture and 49 individuals with pes planus feet were recruited from a university population. Images of the flexor digitorum longus (FDL), flexor hallucis longus (FHL), peroneus longus and brevis (PER), flexor hallucis brevis (FHB), flexor digitorum brevis (FDB) and abductor hallucis (AbH) muscles and the plantar fascia were obtained using a Venue 40 ultrasound system with a 5-13 MHz transducer. The CSA and thickness of AbH, FHB and PER muscles were significantly smaller (AbH -12.8% and -6.8%, FHB -8.9% and -7.6%, PER -14.7% and -10%), whilst FDL (28.3% and 15.2%) and FHL (24% and 9.8%) were significantly larger in the pes planus group. The middle (-10.6%) and anterior (-21.7%) portions of the plantar fascia were thinner in pes planus group. Greater CSA and thickness of the extrinsic muscles might reflect compensatory activity to support the MLA if the intrinsic foot muscle function has been compromised by altered foot structure. A thinner plantar fascia suggests reduced load bearing, and regional variations in structure and function in feet with pes planus. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. The role of post-operative radiographs in predicting risk of flexor pollicis longus tendon rupture after volar plate fixation of distal radius fractures - a case control study.

    PubMed

    Selvan, D R; Perry, D; Machin, D G; Brown, D J

    2014-12-01

    Volar plating of distal radius fractures is one of the common procedures performed in trauma surgery. Flexor pollicis longus (FPL) rupture has been described as complication following volar plating of distal radius fractures. The aim of our study was to investigate the possible relation between parameters measured on post-operative radiographs and the occurrence of FPL ruptures. This was a case control study. The post-operative radiographs of 11 FPL rupture, and 22 non-FPL rupture patients were reviewed with respect to fracture reduction and plate position and the various parameters were calculated by five independent people. Logistic regression was used to examine the importance of the variables. We identified two significant factors to predict FPL rupture after volar plating of distal radial fractures. These were radial tilt and plate distance from the joint line. The odds ratio of ruptures was 0.74 (95% CI 0.57-0.95) for every degree of radial tilt <25° and 0.50 (95% CI 0.28-0.88) for every millimetre that the distal end of the plate was away from the volar lip of the distal radius at the wrist joint. Post-operative radiographs could help us predict FPL rupture after distal radius volar plating. The findings also highlight the need for good fracture reduction and thoughtful placement of the volar plate intraoperatively to minimise the risk of FPL tendon rupture. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Inferring Muscle-Tendon Unit Power from Ankle Joint Power during the Push-Off Phase of Human Walking: Insights from a Multiarticular EMG-Driven Model.

    PubMed

    Honert, Eric C; Zelik, Karl E

    2016-01-01

    Inverse dynamics joint kinetics are often used to infer contributions from underlying groups of muscle-tendon units (MTUs). However, such interpretations are confounded by multiarticular (multi-joint) musculature, which can cause inverse dynamics to over- or under-estimate net MTU power. Misestimation of MTU power could lead to incorrect scientific conclusions, or to empirical estimates that misguide musculoskeletal simulations, assistive device designs, or clinical interventions. The objective of this study was to investigate the degree to which ankle joint power overestimates net plantarflexor MTU power during the Push-off phase of walking, due to the behavior of the flexor digitorum and hallucis longus (FDHL)-multiarticular MTUs crossing the ankle and metatarsophalangeal (toe) joints. We performed a gait analysis study on six healthy participants, recording ground reaction forces, kinematics, and electromyography (EMG). Empirical data were input into an EMG-driven musculoskeletal model to estimate ankle power. This model enabled us to parse contributions from mono- and multi-articular MTUs, and required only one scaling and one time delay factor for each subject and speed, which were solved for based on empirical data. Net plantarflexing MTU power was computed by the model and quantitatively compared to inverse dynamics ankle power. The EMG-driven model was able to reproduce inverse dynamics ankle power across a range of gait speeds (R2 ≥ 0.97), while also providing MTU-specific power estimates. We found that FDHL dynamics caused ankle power to slightly overestimate net plantarflexor MTU power, but only by ~2-7%. During Push-off, FDHL MTU dynamics do not substantially confound the inference of net plantarflexor MTU power from inverse dynamics ankle power. However, other methodological limitations may cause inverse dynamics to overestimate net MTU power; for instance, due to rigid-body foot assumptions. Moving forward, the EMG-driven modeling approach presented

  14. Musculoskeletal management of a patient with a history of chronic ankle sprains: identifying rupture of peroneal brevis and peroneal longus with diagnostic ultrasonography.

    PubMed

    Bruin, Dick B; von Piekartz, Harry

    2014-09-01

    The purpose of this case report is to describe the use of mobilization and eccentric exercise training for a patient with ankle pain and a history of chronic ankle sprains and discuss the course of diagnostic decision making when the patient did not respond to care. A 48-year-old police officer who had sustained multiple ankle sprains throughout his life presented with pain and restriction in his ability to walk, run, and work. The Global Rating of Change Scale score was - 6, the Numeric Pain Rating Scale score was 7/10, and the Lower Extremity Functional Scale score was - 33. Palpation of the peroneus longus and brevis muscles and inversion with overpressure reproduced the chief concern (Numeric Pain Rating Scale 7/10). The patient was initially diagnosed with chronic peroneal tendinopathy. Treatment included lateral translation mobilization of the talocrural joint combined with eccentric exercise using an elastic band for the peroneal muscles. The patient reported improvement in pain and function during the course of intervention but not as rapidly as expected. Therefore, follow-up ultrasonographic imaging and radiography were performed. These studies revealed partial rupture of the peroneal brevis muscle and total rupture of the peroneal longus muscle. A patient with long-term concerns of the foot complex with a diagnosis of peroneal tendinopathy showed slight improvement with eccentric exercises combined with manual therapy of the talocrural joint. After a course of treatment but minimal response, a diagnosis of tendon rupture was confirmed with diagnostic ultrasonography. Clinicians should be aware that when injuries do not improve with care, tendon rupture should be considered.

  15. Ultrasound-guided steroid tendon sheath injections in juvenile idiopathic arthritis: a 10-year single-center retrospective study.

    PubMed

    Peters, Shannon E; Laxer, Ronald M; Connolly, Bairbre L; Parra, Dimitri A

    2017-04-11

    The aims of this study were to: (a) Identify tendon sheaths most commonly treated with steroid injections in a pediatric patient population with Juvenile Idiopathic Arthritis (JIA); (b) Describe technical aspects of the procedure; (c) Characterize sonographic appearance of tenosynovitis in JIA; (d) Assess agreement between clinical request and sites injected. This was a 10 year single-center retrospective study (May 2006-April 2016) of patients with JIA referred by Rheumatology for ultrasound-guided tendon sheath injections. Patient demographics, clinical referral information, sonographic appearance of the tendon sheaths and technical aspects of the procedure were analyzed. There were 308 procedures of 244 patients (75% female, mean age 9.6 years) who underwent a total of 926 tendon sheath injections. Ankle tendons were most commonly injected (84.9%), specifically the tendon sheaths of tibialis posterior (22.3%), peroneus longus (20%) and brevis (19.7%). The majority of treated sites (91.9%) showed peritendinous fluid and sheath thickening on ultrasound. There were 2 minor intra-procedure complications without sequelae. A good agreement between clinical request and sites injected was observed. Ultrasound-guided tendon sheath injections with steroids are used frequently to treat patients with JIA. It is a safe intervention with a high technical success rate. The ankle region, specifically the medial compartment, is the site most commonly injected in this group of patients. The most common sonographic finding is peritendinous fluid and sheath thickening. These findings might assist clinicians and radiologists to characterize and more effectively manage tenosynovitis in patients with JIA.

  16. Contributions of foot muscles and plantar fascia morphology to foot posture.

    PubMed

    Angin, Salih; Mickle, Karen J; Nester, Christopher J

    2018-03-01

    The plantar foot muscles and plantar fascia differ between different foot postures. However, how each individual plantar structure contribute to foot posture has not been explored. The purpose of this study was to investigate the associations between static foot posture and morphology of plantar foot muscles and plantar fascia and thus the contributions of these structures to static foot posture. A total of 111 participants were recruited, 43 were classified as having pes planus and 68 as having normal foot posture using Foot Posture Index assessment tool. Images from the flexor digitorum longus (FDL), flexor hallucis longus (FHL), peroneus longus and brevis (PER), flexor hallucis brevis (FHB), flexor digitorum brevis (FDB) and abductor hallucis (AbH) muscles, and the calcaneal (PF1), middle (PF2) and metatarsal (PF3) regions of the plantar fascia were obtained using a Venue 40 ultrasound system with a 5-13 MHz transducer. In order of decreasing contribution, PF3 > FHB > FHL > PER > FDB were all associated with FPI and able to explain 69% of the change in FPI scores. PF3 was the highest contributor explaining 52% of increases in FPI score. Decreased thickness was associated with increased FPI score. Smaller cross sectional area (CSA) in FHB and PER muscles explained 20% and 8% of increase in FPI score. Larger CSA of FDB and FHL muscles explained 4% and 14% increase in FPI score respectively. The medial plantar structures and the plantar fascia appear to be the major contributors to static foot posture. Elucidating the individual contribution of multiple muscles of the foot could provide insight about their role in the foot posture. Copyright © 2018. Published by Elsevier B.V.

  17. Lengthening osteotomy of the calcaneus and flexor digitorum longus tendon transfer in flexible flatfoot deformity improves talo-1st metatarsal-Index, clinical outcome and pedographic parameter.

    PubMed

    Richter, Martinus; Zech, Stefan

    2013-03-01

    Lengthening osteotomy of the calcaneus (LO) and flexor digitorum longus tendon (FDL) transfer to the navicular is one option for the treatment of flexible flatfoot deformity (FD). The aim of the study was to analyse the amount of correction and clinical outcome including pedographic assessment. In a prospective consecutive non-controlled clinical followup study, all patients with FD that were treated with LO and FDL from September 1st 2006 to August 31st, 2009 were included. Assessment was performed before surgery and at 2-year-followup including clinical examination (with staging of posterior tibialis insufficiency) weight bearing radiographs (Talo-1st metatarsal angles (TMT)), pedography (increased midfoot contact area and force) and Visual Analogue Scale Foot and Ankle (VAS FA). 112 feet in 102 patients were analysed (age, 57.6 (13-82), 42% male). In 12 feet (9%) wound healing delay without further surgical measures was registered. All patients achieved full weight bearing during the 7th postoperative week. Until followup, revision surgery was done in 3 patients (fusion calcaneocuboid joint (n=2), correction triple arthrodesis (n=1)). 101 feet (90%) completed 2-year-followup. TMT dorsoplantar/lateral/Index and VAS FA scores were increased, and posterior tibialis insufficiency stage, pedographic midfoot contact area and force percentage were decreased (each p<.05). All relevant parameters (stage of posterior tibialis insufficiency, TMT angles and Index, pedographic midfoot contact area and force percentage, VAS FA) were improved 2 years after LO and FDL transfer to the navicular in FD. The complication rate was low. This method allows safe and predictable correction. Copyright © 2012 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  18. Biomechanical Analysis of Suture Anchor vs Tenodesis Screw for FHL Transfer.

    PubMed

    Drakos, Mark C; Gott, Michael; Karnovsky, Sydney C; Murphy, Conor I; DeSandis, Bridget A; Chinitz, Noah; Grande, Daniel; Chahine, Nadeen

    2017-07-01

    Chronic Achilles injury is often treated with flexor hallucis longus (FHL) tendon transfer to the calcaneus using 1 or 2 incisions. A single incision avoids the risks of extended dissections yet yields smaller grafts, which may limit fixation options. We investigated the required length of FHL autograft and biomechanical profiles for suture anchor and biotenodesis screw fixation. Single-incision FHL transfer with suture anchor or biotenodesis screw fixation to the calcaneus was performed on 20 fresh cadaveric specimens. Specimens were cyclically loaded until maximal load to failure. Length of FHL tendon harvest, ultimate load, stiffness, and mode of failure were recorded. Tendon harvest length needed for suture anchor fixation was 16.8 ± 2.1 mm vs 29.6 ± 2.4 mm for biotenodesis screw ( P = .002). Ultimate load to failure was not significantly different between groups. A significant inverse correlation existed between failure load and donor age when all specimens were pooled (ρ = -0.49, P < .05). Screws in younger specimens (fewer than 70) resulted in significantly greater failure loads ( P < .03). No difference in stiffness was found between groups. Modes of failure for screw fixation were either tunnel pullout (n = 6) or tendon rupture (n = 4). Anchor failure occurred mostly by suture breakage (n = 8). Adequate FHL tendon length could be harvested through a single posterior incision for fixation to the calcaneus with either fixation option, but suture anchor required significantly less graft length. Stiffness, fixation strength, and load to failure were comparable between groups. An inverse correlation existed between failure load and donor age. Younger specimens with screw fixation demonstrated significantly greater failure loads. Adequate harvest length for FHL transfer could be achieved with a single posterior incision. There was no difference in strength of fixation between suture anchor and biotenodesis screw.

  19. Peroneus longus stretch reflex amplitude increases after ankle brace application

    PubMed Central

    Cordova, M; Ingersoll, C

    2003-01-01

    Background: The use of external ankle support is widespread throughout sports medicine. However, the application of ankle bracing to a healthy ankle over a long period has been scrutinised because of possible neuromuscular adaptations resulting in diminished dynamic support offered by the peroneus longus. Objective: To investigate the immediate and chronic effects of ankle brace application on the amplitude of peroneus longus stretch reflex. Methods: Twenty physically active college students (mean (SD) age 23.6 (1.7) years, height 168.7 (8.4) cm, and mass 69.9 (12.0) kg) who had been free from lower extremity pathology for the 12 months preceding the study served as subjects. None had been involved in a strength training or conditioning programme in the six months preceding the study. A 3 x 3 x 2 (test condition x treatment condition x time) design with repeated measures on the first and third factor was used. The peroneus longus stretch reflex (% of maximum amplitude) during sudden foot inversion was evaluated under three ankle brace conditions (control, lace up, and semi-rigid) before and after eight weeks of ankle brace use. Results: A 3 x 3 x 2 repeated measures analysis of variance showed that peroneus longus stretch reflex amplitude increased immediately after application of a lace up brace (67.1 (4.4)) compared with the semi-rigid (57.9 (4.3)) and control (59.0 (5.2)) conditions (p<0.05). Peroneus longus stretch reflex also increased after eight weeks of use of the semi-rigid brace compared with the lace up and control conditions (p<0.05). Conclusions: Initial application of a lace up style ankle brace and chronic use of a semi-rigid brace facilitates the amplitude of the peroneus longus stretch reflex. It appears that initial and long term ankle brace use does not diminish the magnitude of this stretch reflex in the healthy ankle. PMID:12782553

  20. One-stage treatment of delayed 'jersey finger' by Z-step lengthening of the flexor digitorum profundus tendon at the wrist.

    PubMed

    Sawaya, Elias T; Choughri, Hussein; Pelissier, Philippe

    2012-02-01

    The authors report the case of a 19-year-old female with delayed presentation of a type II 'jersey finger' of the fourth dominant digit. A surgical approach was performed, revealing a retracted flexor digitorum profundus tendon within a still patent sheath. The resulting loss of tendon length overruled any possibility of direct reinsertion of the tendon. A lengthening "Z-step" tendinoplasty was then performed on the tendon at the wrist, thus enabling reinsertion at the base of the distal phalanx. The patient then underwent conventional splinting and physiotherapy. Total Active Motion was measured at 220° with a 6-month follow-up. Even though there is no clear consensus concerning management of such cases, different techniques have been described, such as one- or two-stage grafting, or tenotomy at the musculotendinous junction. Lengthening tendinoplasties have been applied by certain authors but only to the flexor pollicis longus tendon. To our knowledge, this is the only reported case of lengthening Z-step applied to a long digit for the repair of type II 'jersey finger' lesions. The satisfactory functional and cosmetic outcome encourages us to consider this one-stage technique in other select cases, in order to gather more formal evidence. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  1. Inferring Muscle-Tendon Unit Power from Ankle Joint Power during the Push-Off Phase of Human Walking: Insights from a Multiarticular EMG-Driven Model

    PubMed Central

    2016-01-01

    Introduction Inverse dynamics joint kinetics are often used to infer contributions from underlying groups of muscle-tendon units (MTUs). However, such interpretations are confounded by multiarticular (multi-joint) musculature, which can cause inverse dynamics to over- or under-estimate net MTU power. Misestimation of MTU power could lead to incorrect scientific conclusions, or to empirical estimates that misguide musculoskeletal simulations, assistive device designs, or clinical interventions. The objective of this study was to investigate the degree to which ankle joint power overestimates net plantarflexor MTU power during the Push-off phase of walking, due to the behavior of the flexor digitorum and hallucis longus (FDHL)–multiarticular MTUs crossing the ankle and metatarsophalangeal (toe) joints. Methods We performed a gait analysis study on six healthy participants, recording ground reaction forces, kinematics, and electromyography (EMG). Empirical data were input into an EMG-driven musculoskeletal model to estimate ankle power. This model enabled us to parse contributions from mono- and multi-articular MTUs, and required only one scaling and one time delay factor for each subject and speed, which were solved for based on empirical data. Net plantarflexing MTU power was computed by the model and quantitatively compared to inverse dynamics ankle power. Results The EMG-driven model was able to reproduce inverse dynamics ankle power across a range of gait speeds (R2 ≥ 0.97), while also providing MTU-specific power estimates. We found that FDHL dynamics caused ankle power to slightly overestimate net plantarflexor MTU power, but only by ~2–7%. Conclusions During Push-off, FDHL MTU dynamics do not substantially confound the inference of net plantarflexor MTU power from inverse dynamics ankle power. However, other methodological limitations may cause inverse dynamics to overestimate net MTU power; for instance, due to rigid-body foot assumptions. Moving

  2. Changes in skeletal muscle and tendon structure and function following genetic inactivation of myostatin in rats

    PubMed Central

    Mendias, Christopher L; Lynch, Evan B; Gumucio, Jonathan P; Flood, Michael D; Rittman, Danielle S; Van Pelt, Douglas W; Roche, Stuart M; Davis, Carol S

    2015-01-01

    Myostatin is a negative regulator of skeletal muscle and tendon mass. Myostatin deficiency has been well studied in mice, but limited data are available on how myostatin regulates the structure and function of muscles and tendons of larger animals. We hypothesized that, in comparison to wild-type (MSTN+/+) rats, rats in which zinc finger nucleases were used to genetically inactivate myostatin (MSTNΔ/Δ) would exhibit an increase in muscle mass and total force production, a reduction in specific force, an accumulation of type II fibres and a decrease and stiffening of connective tissue. Overall, the muscle and tendon phenotype of myostatin-deficient rats was markedly different from that of myostatin-deficient mice, which have impaired contractility and pathological changes to fibres and their extracellular matrix. Extensor digitorum longus and soleus muscles of MSTNΔ/Δ rats demonstrated 20–33% increases in mass, 35–45% increases in fibre number, 20–57% increases in isometric force and no differences in specific force. The insulin-like growth factor-1 pathway was activated to a greater extent in MSTNΔ/Δ muscles, but no substantial differences in atrophy-related genes were observed. Tendons of MSTNΔ/Δ rats had a 20% reduction in peak strain, with no differences in mass, peak stress or stiffness. The general morphology and gene expression patterns were similar between tendons of both genotypes. This large rodent model of myostatin deficiency did not have the negative consequences to muscle fibres and extracellular matrix observed in mouse models, and suggests that the greatest impact of myostatin in the regulation of muscle mass may not be to induce atrophy directly, but rather to block hypertrophy signalling. PMID:25640143

  3. Surface Modification with Chemically Modified Synovial Fluid for Flexor Tendon Reconstruction in a Canine Model in Vivo

    PubMed Central

    Ji, Xiaoxi; Reisdorf, Ramona L.; Thoreson, Andrew R.; Berglund, Lawrence R.; Moran, Steven L.; Jay, Gregory D.; An, Kai-Nan; Amadio, Peter C.; Zhao, Chunfeng

    2015-01-01

    Background: Functional restoration is the major concern after flexor tendon reconstruction in the hand. The purpose of the present study was to investigate the effects of modifying the surface of extrasynovial tendon autografts with carbodiimide-derivatized synovial fluid with gelatin (cd-SF-G) on functional outcomes of flexor tendon reconstruction using a canine model. Methods: The second and fifth flexor digitorum profundus tendons from eleven dogs were transected and repaired in zone II. The dogs then had six weeks of free activity leading to tendon rupture and scar formation (the repair-failure phase). In the reconstruction phase, two autologous peroneus longus tendons from each dog were harvested; one tendon was coated with cd-SF-G and the other, with saline solution, as a control. A non-weight-bearing rehabilitation protocol was followed for six weeks after reconstruction. The digits were then harvested and evaluations of function, adhesion status, gliding resistance, attachment strength, cell viability, and histology were performed. Results: The tendons coated with cd-SF-G demonstrated significantly lower values (mean and standard deviation) compared with the saline-solution group for work of flexion (0.63 ± 0.24 versus 1.34 ± 0.42 N-mm/deg), adhesion score (3.5 ± 1.6 versus 6.1 ± 1.3), proximal adhesion breaking force (8.6 ± 3.2 versus 20.2 ± 10.2 N), and gliding resistance (0.26 ± 0.08 versus 0.46 ± 0.22 N) (p < 0.05). There was no significant difference between the cd-SF-G and saline-solution groups (p > 0.05) in distal attachment-site strength (56.9 ± 28.4 versus 77.2 ± 36.2 N), stiffness (19 ± 7.5 versus 24.5 ± 14.5 N/mm), and compressive modulus from indentation testing (4.37 ± 1.26 versus 3.98 ± 1.24 N/mm). Histological analysis showed that tendons coated with cd-SF-G had smoother surfaces and demonstrated tendon-to-bone and tendon-to-tendon incorporation. No significant difference in viable cell count between the two groups was observed

  4. Frequency of palmaris longus absence and its association with other anatomical variations in the Egyptian population.

    PubMed

    Raouf, Hoda Abdel; Kader, Ghada Abdel; Jaradat, Ahmed; Dharap, Amol; Fadel, Raouf; Salem, Abdel Halim

    2013-07-01

    The palmaris longus (PL) is one of the most variable muscles in the human body. Racial differences in its variation have been documented. Several studies have attempted to correlate PL absence with other anatomical variations. This study was conducted to determine the prevalence of absence of PL, correlate it with gender and body side and to determine its association with other anatomical variations in the Egyptian population. The presence of PL was clinically determined in 386 Egyptians using the standard technique. All subjects were examined for the presence of the flexor digitorum superficialis (FDS) to the fifth finger. Allen's test was done to assess the completeness of the superficial palmar arch (SPA). The overall prevalence of absence of the PL in Egyptian subjects was 50.8%. There was no significant difference in PL absence with regard to the body side but a significant difference was seen as regards gender and when bilateral absence of PL was compared to its unilateral absence. Absence of FDS tendon to the fifth finger was seen in 1.3% subjects. There was no association between the absence of the FDS tendon to the fifth finger and either presence or absence of PL and also between the absence of PL and the incompleteness of SPA in both genders. In conclusion, the prevalence of absence of PL in the Egyptian population represents one of the highest rates of absence to be reported for this muscle, which is significantly different from that in other ethnic groups. Copyright © 2013 Wiley Periodicals, Inc.

  5. Tendon transfer fixation: comparing a tendon to tendon technique vs. bioabsorbable interference-fit screw fixation.

    PubMed

    Sabonghy, Eric Peter; Wood, Robert Michael; Ambrose, Catherine Glauber; McGarvey, William Christopher; Clanton, Thomas Oscar

    2003-03-01

    Tendon transfer techniques in the foot and ankle are used for tendon ruptures, deformities, and instabilities. This fresh cadaver study compares the tendon fixation strength in 10 paired specimens by performing a tendon to tendon fixation technique or using 7 x 20-25 mm bioabsorbable interference-fit screw tendon fixation technique. Load at failure of the tendon to tendon fixation method averaged 279N (Standard Deviation 81N) and the bioabsorbable screw 148N (Standard Deviation 72N) [p = 0.0008]. Bioabsorbable interference-fit screws in these specimens show decreased fixation strength relative to the traditional fixation technique. However, the mean bioabsorbable screw fixation strength of 148N provides physiologic strength at the tendon-bone interface.

  6. Velopharyngeal closure and the longus capitis muscle.

    PubMed

    Yamawaki, Y; Nishimura, Y; Suzuki, Y

    1996-09-01

    The dynamic mechanism of velopharyngeal function not only in normal individuals but also in patients with velopharyngeal insufficiency, which is mainly related to cleft palate, has been the subject of considerable interest and controversy. Recently, in order to clarify velopharyngeal movement in the valvular action on phonation we examined dynamic MR images of this area taken in the transverse plane in parallel with the muscle sling of levator veli palatini. In cases in whom the closure pattern in that plane is circular, detailed observation revealed a very interesting result; that is, the longus capitis muscle, one of the group of anterior vertebral muscles, is directly involved in velopharyngeal valving function. It has not previously been reported that the longus capitis muscle acts as one of the velopharyngeal closure muscles, in addition to levator veli palatini. The present study demonstrated that contraction of the muscle contributed to velopharyngeal closure by forward movement of the pharyngeal wall.

  7. Tendon injuries

    PubMed Central

    Wu, Fan; Nerlich, Michael; Docheva, Denitsa

    2017-01-01

    Tendons connect muscles to bones, ensuring joint movement. With advanced age, tendons become more prone to degeneration followed by injuries. Tendon repair often requires lengthy periods of rehabilitation, especially in elderly patients. Existing medical and surgical treatments often fail to regain full tendon function. The development of novel treatment methods has been hampered due to limited understanding of basic tendon biology. Recently, it was discovered that tendons, similar to other mesenchymal tissues, contain tendon stem/progenitor cells (TSPCs) which possess the common stem cell properties. The current strategies for enhancing tendon repair consist mainly of applying stem cells, growth factors, natural and artificial biomaterials alone or in combination. In this review, we summarise the basic biology of tendon tissues and provide an update on the latest repair proposals for tendon tears. Cite this article: EFORT Open Rev 2017;2:332-342. DOI: 10.1302/2058-5241.2.160075 PMID:28828182

  8. Intramuscular Electrical Stimulation for Muscle Activation of the Tibialis Anterior After Surgical Repair: A Case Report.

    PubMed

    Hollis, Sharon; McClure, Philip

    2017-12-01

    Background Loss of voluntary activation of musculature can result in muscle weakness. External neuromuscular stimulation can be utilized to improve voluntary activation but is often poorly tolerated because of pain associated with required stimulus level. Intramuscular electrical stimulation requires much lower voltage and may be better tolerated, and therefore more effective at restoring voluntary muscle activation. Case Description A 71-year-old man sustained a rupture of the distal attachment of the tibialis anterior tendon. Thirty-two weeks after surgical repair, there was no palpable or visible tension development in the muscle belly or tendon. Dorsiflexion was dependent on toe extensors. Electrical stimulation applied via a dry needling placement in the muscle belly was utilized to induce an isometric contraction. Outcomes Five sessions of intramuscular electrical stimulation were delivered. By day 4 (second visit), the patient was able to dorsiflex without prominent use of the extensor hallucis longus. By day 6 (third visit), active-range-of-motion dorsiflexion with toes flexed increased 20° (-10° to 10°). Eighteen days after the initial treatment, the patient walked without his previous high-step gait pattern, and the tibialis anterior muscle test improved to withstanding moderate resistance (manual muscle test score, 4/5). Discussion The rapid change in muscle function observed suggests that intramuscular electrical stimulation may facilitate voluntary muscle activation. Level of Evidence Therapy, level 5. J Orthop Sports Phys Ther 2017;47(12):965-969. Epub 15 Oct 2017. doi:10.2519/jospt.2017.7368.

  9. Lipofibromatous Hamartoma of the Plantar Nerve An Extremely Rare Localization.

    PubMed

    Mert, Murat; Hacısalihoglu, Payam

    2018-03-01

    Lipofibromatous hamartoma (LFH) is a rare, benign, tumor-like soft-tissue lesion that affects the peripheral nerves and forms a palpable neurogenic mass. Lipofibromatous hamartoma is associated with pain and sensory and/or motor deficits in the area of innervation of the affected nerve. This report describes a rare case of LFH of the plantar nerve. A 48-year-old woman presented to our outpatient orthopedic clinic with pain and a burning sensation on her left foot. The patient had a history of Morton's neuroma and had undergone a tarsal tunnel operation 2 years earlier at another center. None of her symptoms was alleviated by two previous operations. Magnetic resonance imaging with contrast revealed tenosynovitis of the flexor hallucis longus tendon and signal changes at deep tissue planes of the foot at the levels of the second and third toes, on the dorsal site and subcutaneous soft-tissue planes, suggesting edema and Morton's neuroma. The lesion was excised under spinal anesthesia, and histopathologic examination of the specimen revealed a diagnosis of LFH. The patient was discharged without any symptoms and her foot was normal at 8-month outpatient follow-up, with no indications of postoperative complications and/or recurrence.

  10. Does the longus colli have an effect on cervical vertigo?

    PubMed Central

    Liu, Xiao-Ming; Pan, Fu-Min; Yong, Zhi-Yao; Ba, Zhao-yu; Wang, Shan-Jin; Liu, Zheng; Zhao, Wei-dong; Wu, De-Sheng

    2017-01-01

    Abstract The aim of the study was to evaluate the role of the longus colli muscles in cervical vertigo. We retrospectively analyzed 116 adult patients who underwent anterior cervical discectomy and fusion (ACDF) during 2014 in our department. Patients were assigned to the vertigo group or the nonvertigo group. Demographic data were recorded. Inner distance and cross-sectional area (CSA) of longus colli were measured using coronal magnetic resonance imaging (MRI). The vertigo group (n = 44) and the nonvertigo group (n = 72) were similar in demographic data. Mean preoperative Japanese Orthopaedic Association (JOA) score was higher in the vertigo group than in the nonvertigo group (P = 0.037), but no difference postoperatively. Mean JOA scores increased significantly postoperatively in both groups (P = 0.002 and P = 0.001). The mean vertigo score decreased significantly from pre- to postoperatively in the vertigo group (P = 0.023). The mean preoperative Cobb angle was significantly smaller in the vertigo group than in the nonvertigo group (P <0.001), but no significant difference postoperatively. After ACDF, the mean Cobb angle increased significantly in the vertigo group (P <0.001). The instability rates of C3/4 and C4/5 were significantly higher in the vertigo group (P <0.001 and P <0.001). The inner distance of longus colli was significantly shorter (P = 0.032 and P = 0.026) and CSA significantly smaller (P = 0.041 and P = 0.035), at C3/4 and C4/5 in the vertigo group than in the nonvertigo group. Mean Miyazaki scores were significantly higher in the vertigo group at C3/4 and C4/5 (P = 0.044 and P = 0.037). Moreover, a shorter inner distance and smaller CSA were related to a higher Miyazaki score. Inner distance and cross-sectional area (CSA) of longus colli are associated closely with cervical vertigo. Shorter inner distance and smaller CSA of the longus colli muscles might be risk factors for cervical vertigo. ACDF

  11. Comparison of two intramedullary nails for tibiotalocalcaneal fusion: anatomic and radiographic considerations.

    PubMed

    Mückley, Thomas; Ullm, Sebastian; Petrovitch, Alexander; Klos, Kajetan; Beimel, Claudia; Fröber, Rosemarie; Hofmann, Gunther O

    2007-05-01

    Retrograde intramedullary nailing is an established procedure for tibiotalocalcaneal arthrodesis. This study was conducted to see whether, and if so to what extent, nail design modifications would influence the risk to anatomic structures and the bony coverage of the nail base. Six pairs of thawed fresh-frozen cadaver legs received two different intramedullary nails (N1: straight nail, lateral-medial tip locking; N2: valgus-curved nail, medial-lateral tip locking) under simulated operative conditions. The specimens were dissected; distances between the at-risk structures and the hardware were measured. The hindfoot axis and the volume of the intracalcaneal nail portion were determined with CT. At the plantar entry site, N2 was significantly farther from the flexor hallucis longus tendon (p=0.047), the medial plantar artery (p=0.026), and the lateral plantar nerve (p=0.026) than N1. The lateral-medial calcaneal locking screw of N1 damaged significantly more often the peroneus brevis tendon (p=0.03) than N2. The proximal tip-locking screw, N2, was significantly farther from the anterior tibial artery (p=0.075) and the deep (p=0.047) and superficial peroneal nerves (p=0.009) than N1; N1 was significantly farther from the great saphenous vein (p=0.075) than N2. The distal tip-locking screw, N1. damaged significantly more often the extensor digitorum longus (p=0.007), the anterior tibial artery(p = 0.04), and the deep and superficial peroneal nerves (p=0.03) than N2. CT did not show any significant changes in the hindfoot axis with either device; intracalcaneal nail volumes were similar. A curved nail can increase the distance to at-risk plantar structures. Medial-lateral nail-tip locking appears to have less risk to neurovascular structures. Safer retrograde intramedullary nailing for tibiotalocalcaneal fusion requires knowledge of the structures at risk and appropriate operative technique.

  12. Effects of Achilles tendon vibration, surface and visual conditions on lower leg electromyography in young adults with and without recurrent ankle sprains.

    PubMed

    Lubetzky, Anat V; Price, Robert; McCoy, Sarah W

    2016-07-01

    Functional ankle instability is associated with decreased ankle muscle function. Compliant surfaces and eyes-closed training are commonly used for rehabilitation and prevention of ankle sprains. Brief Achilles tendon vibration is commonly used in the study of postural control. To test the level of activation of tibialis anterior (TIB) and fibularis longus (FIB), bilateral Achilles tendon vibration was applied for the middle 20 s in a series of 60-s trials, when 10 healthy young adults and 10 adults with history of repeated ankle sprains were standing bipedal: on floor, on memory foam, or on a Both Sides Up (BOSU) ball, with eyes open, and on floor and foam with eyes closed. Differences in Integrated surface electromyography (IEMG) of TIB and FIB were significant for both groups pre, during, and post vibration (Friedman Tests, p < 0.001 for all). In both groups, the highest IEMG for TIB was obtained during vibration when standing on foam with eyes closed, whereas the highest IEMG for FIB was obtained during vibration when standing on the BOSU. Bipedal stance on BOSU and brief Achilles tendon vibration may be a useful intervention when a session's goal is to facilitate lower leg muscles activation. Future research should explore training effects as well as the effect of FIB tendon vibration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Silicone infusion tubing instead of Hunter rods for two-stage zone 2 flexor tendon reconstruction in a resource-limited surgical environment.

    PubMed

    Kibadi, K; Moutet, F

    2017-10-01

    The authors describe their experience using silicone infusion tubing in place of Hunter rods for two-stage zone 2 flexor tendon reconstruction in a resource-limited surgical environment. This case report features a 47-year-old, right-handed man who had no active PIP and DIP joint flexion in four fingers of the right hand 5 months after an injury. During the first repair stage, the A2 and A4 pulleys were reconstructed using an extensor retinaculum graft. An infusion tube was inserted instead of Hunter rods. During the second stage, formation of a digital neo-canal around the infusion tubing was observed. The infusion tubing was removed and replaced with a palmaris longus tendon graft according to the conventional technique. Physiotherapy and rehabilitation followed surgery. At 6 months, very significant progress had been made with complete recovery of PIP and DIP flexion in the four fingers. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

  14. Plantar fascia anatomy and its relationship with Achilles tendon and paratenon

    PubMed Central

    Stecco, Carla; Corradin, Marco; Macchi, Veronica; Morra, Aldo; Porzionato, Andrea; Biz, Carlo; De Caro, Raffaele

    2013-01-01

    Although the plantar fascia (PF) has been studied quite well from a biomechanical viewpoint, its microscopic properties have been overlooked: nothing is known about its content of elastic fibers, the features of the extracellular matrix or the extent of innervation. From a functional and clinical standpoint, the PF is often correlated with the triceps surae muscle, but the anatomical grounds for this link are not clear. The aim of this work was to focus on the PF macroscopic and microscopic properties and study how Achilles tendon diseases might affect it. Twelve feet from unembalmed human cadavers were dissected to isolate the PF. Specimens from each PF were tested with various histological and immunohistochemical stains. In a second stage, 52 magnetic resonance images (MRI) obtained from patients complaining of aspecific ankle or foot pain were analyzed, dividing the cases into two groups based on the presence or absence of signs of degeneration and/or inflammation of the Achilles tendon. The thickness of PF and paratenon was assessed in the two groups and statistical analyses were conducted. The PF is a tissue firmly joined to plantar muscles and skin. Analyzing its possible connections to the sural structures showed that this fascia is more closely connected to the paratenon of Achilles tendon than to the Achilles tendon, through the periosteum of the heel. The PF extended medially and laterally, continuing into the deep fasciae enveloping the abductor hallucis and abductor digiti minimi muscles, respectively. The PF was rich in hyaluronan, probably produced by fibroblastic-like cells described as ‘fasciacytes’. Nerve endings and Pacini and Ruffini corpuscles were present, particularly in the medial and lateral portions, and on the surface of the muscles, suggesting a role for the PF in the proprioception of foot. In the radiological study, 27 of the 52 MRI showed signs of Achilles tendon inflammation and/or degeneration, and the PF was 3.43 ± 0.48 mm

  15. Plantar fascia anatomy and its relationship with Achilles tendon and paratenon.

    PubMed

    Stecco, Carla; Corradin, Marco; Macchi, Veronica; Morra, Aldo; Porzionato, Andrea; Biz, Carlo; De Caro, Raffaele

    2013-12-01

    Although the plantar fascia (PF) has been studied quite well from a biomechanical viewpoint, its microscopic properties have been overlooked: nothing is known about its content of elastic fibers, the features of the extracellular matrix or the extent of innervation. From a functional and clinical standpoint, the PF is often correlated with the triceps surae muscle, but the anatomical grounds for this link are not clear. The aim of this work was to focus on the PF macroscopic and microscopic properties and study how Achilles tendon diseases might affect it. Twelve feet from unembalmed human cadavers were dissected to isolate the PF. Specimens from each PF were tested with various histological and immunohistochemical stains. In a second stage, 52 magnetic resonance images (MRI) obtained from patients complaining of aspecific ankle or foot pain were analyzed, dividing the cases into two groups based on the presence or absence of signs of degeneration and/or inflammation of the Achilles tendon. The thickness of PF and paratenon was assessed in the two groups and statistical analyses were conducted. The PF is a tissue firmly joined to plantar muscles and skin. Analyzing its possible connections to the sural structures showed that this fascia is more closely connected to the paratenon of Achilles tendon than to the Achilles tendon, through the periosteum of the heel. The PF extended medially and laterally, continuing into the deep fasciae enveloping the abductor hallucis and abductor digiti minimi muscles, respectively. The PF was rich in hyaluronan, probably produced by fibroblastic-like cells described as 'fasciacytes'. Nerve endings and Pacini and Ruffini corpuscles were present, particularly in the medial and lateral portions, and on the surface of the muscles, suggesting a role for the PF in the proprioception of foot. In the radiological study, 27 of the 52 MRI showed signs of Achilles tendon inflammation and/or degeneration, and the PF was 3.43 ± 0.48 mm thick

  16. Do Australian Football players have sensitive groins? Players with current groin pain exhibit mechanical hyperalgesia of the adductor tendon.

    PubMed

    Drew, Michael K; Lovell, Gregory; Palsson, Thorvaldur S; Chiarelli, Pauline E; Osmotherly, Peter G

    2016-10-01

    This is the first study to evaluate the mechanical sensitivity, clinical classifications and prevalence of groin pain in Australian football players. Case-control. Professional (n=66) and semi-professional (n=9) Australian football players with and without current or previous groin injuries were recruited. Diagnoses were mapped to the Doha Agreement taxonomy. Point and career prevalence of groin pain was calculated. Pressure pain thresholds (PPTs) were assessed at regional and distant sites using handheld pressure algometry across four sites bilaterally (adductor longus tendon, pubic bone, rectus femoris, tibialis anterior muscle). To assess the relationship between current groin pain and fixed effects of hyperalgesia of each site and a history of groin pain, a mixed-effect logistic regression model was utilised. Receiver Operator Characteristic (ROC) curve were determined for the model. Point prevalence of groin pain in the preseason was 21.9% with a career prevalence of 44.8%. Adductor-related groin pain was the most prevalent classification in the pre-season period. Hyperalgesia was observed in the adductor longus tendon site in athletes with current groin pain (OR=16.27, 95% CI 1.86 to 142.02). The ROC area under the curve of the regression model was fair (AUC=0.76, 95% CI 0.54 to 0.83). Prevalence data indicates that groin pain is a larger issue than published incidence rates imply. Adductor-related groin pain is the most common diagnosis in pre-season in this population. This study has shown that hyperalgesia exists in Australian football players experiencing groin pain indicating the value of assessing mechanical pain sensitivity as a component of the clinical assessment. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  17. Transcription factor EGR1 directs tendon differentiation and promotes tendon repair

    PubMed Central

    Guerquin, Marie-Justine; Charvet, Benjamin; Nourissat, Geoffroy; Havis, Emmanuelle; Ronsin, Olivier; Bonnin, Marie-Ange; Ruggiu, Mathilde; Olivera-Martinez, Isabel; Robert, Nicolas; Lu, Yinhui; Kadler, Karl E.; Baumberger, Tristan; Doursounian, Levon; Berenbaum, Francis; Duprez, Delphine

    2013-01-01

    Tendon formation and repair rely on specific combinations of transcription factors, growth factors, and mechanical parameters that regulate the production and spatial organization of type I collagen. Here, we investigated the function of the zinc finger transcription factor EGR1 in tendon formation, healing, and repair using rodent animal models and mesenchymal stem cells (MSCs). Adult tendons of Egr1–/– mice displayed a deficiency in the expression of tendon genes, including Scx, Col1a1, and Col1a2, and were mechanically weaker compared with their WT littermates. EGR1 was recruited to the Col1a1 and Col2a1 promoters in postnatal mouse tendons in vivo. Egr1 was required for the normal gene response following tendon injury in a mouse model of Achilles tendon healing. Forced Egr1 expression programmed MSCs toward the tendon lineage and promoted the formation of in vitro–engineered tendons from MSCs. The application of EGR1-producing MSCs increased the formation of tendon-like tissues in a rat model of Achilles tendon injury. We provide evidence that the ability of EGR1 to promote tendon differentiation is partially mediated by TGF-β2. This study demonstrates EGR1 involvement in adult tendon formation, healing, and repair and identifies Egr1 as a putative target in tendon repair strategies. PMID:23863709

  18. Safety of achilles detachment and reattachment using a standard midline approach to insertional enthesophytes.

    PubMed

    McAlister, Jeffrey E; Hyer, Christopher F

    2015-01-01

    Detachment with reattachment of the Achilles tendon is a common surgery for debridement of retrocalcaneal exostosis, bursitis, and other insertional pathologic entities. The technique involves a midline skin incision on the posterior Achilles to the tendon. The distal Achilles attachment is removed in a U-shaped manner, leaving the medial and lateral flares, but exposing the posterior spur. This midline approach provides excellent exposure and allows for rapid and efficient surgical debridement. The tendon is reapproximated and repaired with a suture anchor to facilitate fixation to the posterior calcaneus. Some surgeons have expressed concerned that the rupture risk could be increased in the postoperative period using this technique. The present study was a retrospective medical record review of 98 patients (100 feet) who had undergone a midline approach with Achilles reattachment after insertional Achilles debridement during a 3-year period. The demographic and comorbidity data were collected and analyzed. The outcome measures were postoperative rupture and the need for revision surgery. The mean age was 51.9 years, and the patients included 59 females (60.2%) and 39 males (39.8%). The complications included 4 rupture or avulsion revisions (4.0%) and 2 recurrent pain and tendinitis revisions (2.0%). The most common repeat repair procedure included hardware removal and a flexor hallucis longus transfer or augmentation. Nine patients (9.0%) had wound complications, 7 (77.8%) of which necessitated incision and drainage. The midline approach with Achilles detachment and reattachment is a safe and effective method of surgical treatment of insertional Achilles pathologic entities. The low reoperation rate of 4.0% will allow foot and ankle surgeons to safely rely on this approach. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Complex Anatomic Abnormalities of the Lower Leg Muscles and Tendons Associated With Phocomelia: A Case Report.

    PubMed

    Hodo, Thomas; Hamrick, Mark; Melenevsky, Yulia

    Musculoskeletal anatomy is widely known to have components that stray from the norm in the form of variant muscle and tendon presence, absence, origin, insertion, and bifurcation. Although these variant muscles and tendons might be deemed incidental and insignificant findings by most, they can be important contributors to pathologic physiology or, more importantly, an option for effective treatment. In the present case report, we describe a patient with phocomelia and Müllerian abnormalities secondary to in utero thalidomide exposure. The patient had experienced recurrent bilateral foot pain accompanied by numbness, stiffness, swelling, and longstanding pes planus. These symptoms persisted despite conservative treatment with orthotics, steroids, and nonsteroidal anti-inflammatory drugs. Radiographic imaging showed dysmorphic and degenerative changes of the ankle and foot joints. Further investigation with magnetic resonance imaging revealed complex anatomic abnormalities, including the absence of the posterior tibialis and peroneus brevis, lateralization of the peroneus longus, and the presence of a variant anterior compartment muscle. The variant structure was likely a previously described anterior compartment variant, anterior fibulocalcaneus, and might have been a source of the recurrent pain. Also, the absence of the posterior tibialis might have caused the pes planus in the present patient, considering that posterior tibialis tendon dysfunction is the most common cause of acquired pes planus. Although thalidomide infrequently affects the lower extremities, its effects on growth and development were likely the cause of this rare array of anatomic abnormalities and resulting ankle and foot pathologic features. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Decellularized Tendon Extracellular Matrix—A Valuable Approach for Tendon Reconstruction?

    PubMed Central

    Schulze-Tanzil, Gundula; Al-Sadi, Onays; Ertel, Wolfgang; Lohan, Anke

    2012-01-01

    Tendon healing is generally a time-consuming process and often leads to a functionally altered reparative tissue. Using degradable scaffolds for tendon reconstruction still remains a compromise in view of the required high mechanical strength of tendons. Regenerative approaches based on natural decellularized allo- or xenogenic tendon extracellular matrix (ECM) have recently started to attract interest. This ECM combines the advantages of its intrinsic mechanical competence with that of providing tenogenic stimuli for immigrating cells mediated, for example, by the growth factors and other mediators entrapped within the natural ECM. A major restriction for their therapeutic application is the mainly cell-associated immunogenicity of xenogenic or allogenic tissues and, in the case of allogenic tissues, also the risk of disease transmission. A survey of approaches for tendon reconstruction using cell-free tendon ECM is presented here, whereby the problems associated with the decellularization procedures, the success of various recellularization strategies, and the applicable cell types will be thoroughly discussed. Encouraging in vivo results using cell-free ECM, as, for instance, in rabbit models, have already been reported. However, in comparison to native tendon, cells remain mostly inhomogeneously distributed in the reseeded ECM and do not align. Hence, future work should focus on the optimization of tendon ECM decellularization and recolonization strategies to restore tendon functionality. PMID:24710540

  1. Management of acute Achilles tendon rupture with tendon-bundle technique

    PubMed Central

    Li, Chun-Guang; Li, Bing

    2017-01-01

    Objective *These authors contributed equally to this work.To explore tendon-bundle technique for treating Achilles tendon rupture with no defects. Methods Patients with full unilateral Achilles tendon rupture with no defects were included. The Achilles tendon medial edge surgical repair approach was used, revealing horsetail-like rupture bundles. Tendon bundles were anatomically realigned and repaired end-to-end using 5-0 sutures. Patients were followed-up for 1 year, and assessed for differences between the repaired versus healthy limb. Results Out of 24 patients (18 male, 6 female; aged 19–56 years) at 1 year following surgery, mean American Orthopaedic Foot and Ankle Society score was 92.4 ± 5.9; mean differences between the surgically repaired versus contralateral side in dorsiflexion and plantarflexion angle were 3.5 ± 2.3° and 5.6 ± 3.2°, respectively; mean difference in calf circumference between the two sides was 0.9 ± 0.5 cm; and mean increase in Achilles tendon width versus the healthy side was 0.8 ± 0.2 cm. By 1 year post-surgery, there were no significant between-side differences in dorsiflexion and plantarflexion angle, or calf circumference. Conclusions Tendon-bundle surgery resulted in good ankle function restoration and low complication rates. Tendon-bundle surgery may reduce blood supply destruction and maximally preserve Achilles tendon length, and may be effective for treating Achilles tendon rupture with no defects. PMID:28222622

  2. [Ultrastructural observation of tendonization of artificial tendon 109HH in rabbit].

    PubMed

    Liu, L; Cao, Q; Xiao, H

    1995-09-01

    Ten New Zealand rabbits were divided into 5 groups at random. Calcaneal tendons were cut bilaterally, then atificial tendon 109HH was used to connect the two ends of the cut tendon. Ultrastructural changes of control group and experimental groups at 2, 6, 12, 28 weeks after section were observed. The results showed that fibroblast proliferated and a lot of ribosome and RER appeared in plasm during 2 approximately 6 weeks, indicating artificial tendon caused fibroblast proliferation. During this period, fibroblast over synthesized collagenous protein and the synthesis of collagenous fibers peaked. During 12-28 weeks, the number of fibroblasts and the synthesis of collagenous protein decreased. Finally, fibroblasts became inactive tendon cells. With the formation of new tendons, the artificial tendens were degradated and absorbed, and disappeared after 12 weeks. The new tendon fibers became thicker and had the correct direction through reconstruction. The structure and function of new tendons could be restored to be consistent with normal values.

  3. [Rheumatic tendon pathologies].

    PubMed

    Thomas, M; Jordan, M

    2014-11-01

    Rheumatoid arthritis is found in approximately 2 % of the total population in Europe and the peak incidence of the disease is during the fourth and fifth decades of life. In approximately 15 % the first symptoms of the disease occur at the level of the foot and ankle. If the early stage-dependent therapy with pharmaceuticals fails isolated surgery of the tendons (e.g. tenosynovectomy) and reconstructive surgery including the tendons (e.g. tendon transfer and tendon readaptation) are performed to keep the patient mobile. The aim of this article is to give an overview of the most commonly used interventions in the reconstruction of tendons in rheumatism patients and the corresponding indications. The conservative therapy options for rheumatic foot and ankle alterations with a special emphasis on tendon pathologies have a well-established importance and are also presented. A selective literature search was carried out for therapeutic options of rheumatic tendon pathologies. If possible attempts should be made to preserve functional qualities using tenosynovectomy, tendon sutures or tendon transfer operations. If joints are already destroyed or dislocated, tendon operations should be carried out only as combined interventions with arthrodesis, endoprostheses or resection arthroplasty. The time window in which these interventions are possible should not be missed. Orthotic devices, bandages or even orthopedic shoes provide external support and splinting but do not represent a causal therapy.

  4. Computed tomography of calcaneal fractures: anatomy, pathology, dosimetry, and clinical relevance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guyer, B.H.; Levinsohn, E.M.; Fredrickson, B.E.

    1985-11-01

    Eighteen CT examinations were performed in 10 patients for the evaluation of acute intraarticular fractures and their follow-up. Fractures comparable to those in the patients were created in cadavers. The normal anatomy and the traumatically altered anatomy of the calcaneus in the axial, coronal, and sagittal planes are demonstrated by CT and corresponding anatomic sections. Scanning was performed in the axial plane, with subsequent reconstruction in the coronal and sagittal planes. The axial scans show disruption of the inferior part of the posterior facet, calcaneocuboid joint involvement, and widening of the calcaneus. The coronal scans show disruption of the superiormore » part of the posterior facet, sustentaculum tali depression (involvement of middle and anterior facets), peroneal and flexor hallucis longus tendon impingement, and widening and height loss of the calcaneus. The sagittal scans show disruption of the posterior facet, calcaneocuboid joint involvement, and height loss of the calcaneus and allow the evaluation of Boehler's and Gissane's angles. All three planes show the position of major fracture fragments. Radiation dose to the foot was measured to be 0.1 rad (0.001 Gy) for plain film radiography (five exposures), 18 rad (0.18 Gy) for conventional tomography (20 cuts), and 2.6 rad (0.026 Gy) for axial CT examination.« less

  5. Biologics for tendon repair☆

    PubMed Central

    Docheva, Denitsa; Müller, Sebastian A.; Majewski, Martin; Evans, Christopher H.

    2015-01-01

    Tendon injuries are common and present a clinical challenge to orthopedic surgery mainly because these injuries often respond poorly to treatment and require prolonged rehabilitation. Therapeutic options used to repair ruptured tendons have consisted of suture, autografts, allografts, and synthetic prostheses. To date, none of these alternatives has provided a successful long-term solution, and often the restored tendons do not recover their complete strength and functionality. Unfortunately, our understanding of tendon biology lags far behind that of other musculoskeletal tissues, thus impeding the development of new treatment options for tendon conditions. Hence, in this review, after introducing the clinical significance of tendon diseases and the present understanding of tendon biology, we describe and critically assess the current strategies for enhancing tendon repair by biological means. These consist mainly of applying growth factors, stem cells, natural biomaterials and genes, alone or in combination, to the site of tendon damage. A deeper understanding of how tendon tissue and cells operate, combined with practical applications of modern molecular and cellular tools could provide the long awaited breakthrough in designing effective tendon-specific therapeutics and overall improvement of tendon disease management. PMID:25446135

  6. Assessment of the presence/absence of the palmaris longus muscle in different sports, and elite and non-elite sport populations.

    PubMed

    Fowlie, Craig; Fuller, Colin; Pratten, Margaret K

    2012-06-01

    To investigate whether higher presence of the palmaris longus muscle is associated with sports that require hand grip. Cross-sectional study. Six hundred and forty-two medical students, members of sports clubs and national athletes. Participants were invited to complete a questionnaire that assessed their main sport, elite or non-elite level of participation, and level of activity. The presence of the palmaris longus was assessed visually using a standardised test. Presence of the palmaris longus, type of hand grip required for the sport and the level of participation. The presence of the palmaris longus was higher in elite athletes (21/22, 96%) than non-elite athletes (66/84, 79%; P=0.066) for sports that require a dominant-handed or two-handed cylindrical grip (18/22, 82% and 19/35, 54%, respectively; P=0.034). For both elite and non-elite athletes, the presence of the palmaris longus was higher in those participating in sustained grip sports (325/387, 84%) compared with sports that do not require a sustained grip (150/197, 76%; P=0.012). The palmaris longus may provide an advantage in certain types of sport that require hand grip, and for elite athletes participating in sports that require a dominant-handed or two-handed cylindrical hand grip. Orthopaedic specialists considering the use of the palmaris longus for a grafting procedure on an athlete should consider the level of participation and the type of hand grip required in the athlete's sport. Copyright © 2011 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  7. Achilles tendon: US examination

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fornage, B.D.

    Real-time ultrasonography (US) using linear-array probes and a stand-off pad as a ''waterpath'' was performed to evaluate the Achilles tendon in 67 patients (including 24 athletes) believed to have acute or chronic traumatic or inflammatory pathologic conditions. Tendons in 23 patients appeared normal on US scans. The 44 abnormal tendons comprised five complete and four partial ruptures, seven instances of postoperative change, and 28 cases of tendonitis. US depiction of the inner structure of the tendon resulted in the diagnosis of focal abnormalities, including partial ruptures, nodules, and calcifications. Tendonitis was characterized by enlargement and decreased echogenicity of the tendon.more » The normal US appearance of the Achilles tendon is described.« less

  8. Phenytoin accelerates tendon healing in a rat model of Achilles tendon rupture.

    PubMed

    Hajipour, B; Navali, A M; Mohammad, S Ali; Mousavi, G; Akbari, M Gahvechi; Miyandoab, T Maleki; Roshangar, L; Saleh, B Mohammadi; Kermani, T Asvadi; Laleh, F Moutab; Ghabili, M

    2016-01-01

    Tendons are vulnerable to various types of acute or chronic injures. Different methods have been investigated to achieve better healing. Phenytoin is a drug which could stimulate fibroblasts to produce collagen. This experimental study was performed to assess the effect of phenytoin on tendon healing in a rat model of tendon rupture. Thirty healthy rats were divided into 3 groups, 1) Sham group; 2) Tendon rupture; 3) Tendon rupture+phenytoin (100 mg/kg intraperitoneally) for 21 days. On 21st day after tendon injury, the rats were anesthetized and tendon tissue was sampled for studying by light and electron microscopy. Qualitative and quantitative microscopic comparisons of the repair tissues of both groups were made on the 21st day. The results obtained from light and electron microscopy studies showed that tendon tissue healing was significantly better in phenytoin group compared to the control group (p < 0.05). Systemic administration of phenytoin may have a positive effect on tendon healing by increasing fibroblast quantity, fibrillar collagen synthesis, vascularity, and suppressing inflammation (Tab. 2, Ref. 25).

  9. Informing Stem Cell-Based Tendon Tissue Engineering Approaches with Embryonic Tendon Development.

    PubMed

    Okech, William; Kuo, Catherine K

    Adult tendons fail to regenerate normal tissue after injury, and instead form dysfunctional scar tissue with abnormal mechanical properties. Surgical repair with grafts is the current standard to treat injuries, but faces significant limitations including pain and high rates of re-injury. To address this, we aim to regenerate new, normal tendons to replace dysfunctional tendons. A common approach to tendon tissue engineering is to design scaffolds and bioreactors based on adult tendon properties that can direct adult stem cell tenogenesis. Despite significant progress, advances have been limited due, in part, to a need for markers and potent induction cues. Our goal is to develop novel tendon tissue engineering approaches informed by embryonic tendon development. We are characterizing structure-property relationships of embryonic tendon to identify design parameters for three-dimensional scaffolds and bioreactor mechanical loading systems to direct adult stem cell tenogenesis. We will review studies in which we quantified changes in the mechanical and biochemical properties of tendon during embryonic development and elucidated specific mechanisms of functional property elaboration. We then examined the effects of these mechanical and biochemical factors on embryonic tendon cell behavior. Using custom-designed bioreactors, we also examined the effects of dynamic mechanical loading and growth factor treatment on embryonic tendon cells. Our findings have established cues to induce tenogenesis as well as metrics to evaluate differentiation. We finish by discussing how we have evaluated the tenogenic differentiation potential of adult stem cells by comparing their responses to that of embryonic tendon cells in these culture systems.

  10. Muscular force transmission: a unified, dual or multiple system? A review and some explorative experimental results.

    PubMed

    Huijing, P

    1999-10-01

    Structures contributing to force transmission in muscle are reviewed combining some historical and relatively recently published experimental data. Also, effects of aponeurotomy and tenotomy are reviewed shortly as well as some new experimental results regarding these interventions that reinforce the concept of myofascial force transmission. The review is also illustrated by some new images of single muscle fibres from Xenopus Laevis indicative of such transmission and some data about locations of insertion of human gluteus maximus muscle. From this review and the new material, emerges a line of thought indicating that mechanical connections between muscle fibres and intramuscular connective tissue play an important role in force transmission. New experimental observations are presented for non-spanning muscle (i.c., rat biceps femoris muscle), regarding the great variety of types of intramuscular connections that exist i n addition to myo-tendinous junctions at the perimuscular ends of muscle fibres. Such connections are classified as (1) tapered end connections, (2) Myo-myonal junctions, (3) myo-epimysial junctions and (3) Myo-endomysial junctions. This line of thought is followed up by consideration of a possible role of connections of intra- and extramuscular connective tissue in force transmission out of the muscle. Experimental results of an explorative nature, regarding the interactions of extensor digitorum longus (EDL), tibialis anterior (TA) and hallucis longus (HAL) muscles within a relatively intact dorsal flexor compartment of the rat hind leg, indicate that: (1) length force properties of EDL are influenced by TA activity in a length dependent fashion. Depending on TA length, force exerted by EDL, kept at constant origin insertion distance, is variable and the effect is influenced by EDL length itself as well; (2) Force is transmitted from muscle to extramuscular connective tissue and vice versa. As a consequence force exerted at proximal and distal

  11. Fos Promotes Early Stage Teno-Lineage Differentiation of Tendon Stem/Progenitor Cells in Tendon.

    PubMed

    Chen, Jialin; Zhang, Erchen; Zhang, Wei; Liu, Zeyu; Lu, Ping; Zhu, Ting; Yin, Zi; Backman, Ludvig J; Liu, Huanhuan; Chen, Xiao; Ouyang, Hongwei

    2017-11-01

    Stem cells have been widely used in tendon tissue engineering. The lack of refined and controlled differentiation strategy hampers the tendon repair and regeneration. This study aimed to find new effective differentiation factors for stepwise tenogenic differentiation. By microarray screening, the transcript factor Fos was found to be expressed in significantly higher amounts in postnatal Achilles tendon tissue derived from 1 day as compared with 7-days-old rats. It was further confirmed that expression of Fos decreased with time in postnatal rat Achilles tendon, which was accompanied with the decreased expression of multiply tendon markers. The expression of Fos also declined during regular in vitro cell culture, which corresponded to the loss of tendon phenotype. In a cell-sheet and a three-dimensional cell culture model, the expression of Fos was upregulated as compared with in regular cell culture, together with the recovery of tendon phenotype. In addition, significant higher expression of tendon markers was found in Fos-overexpressed tendon stem/progenitor cells (TSPCs), and Fos knock-down gave opposite results. In situ rat tendon repair experiments found more normal tendon-like tissue formed and higher tendon markers expression at 4 weeks postimplantation of Fos-overexpressed TSPCs derived nonscaffold engineering tendon (cell-sheet), as compared with the control group. This study identifies Fos as a new marker and functional driver in the early stage teno-lineage differentiation of tendon, which paves the way for effective stepwise tendon differentiation and future tendon regeneration. Stem Cells Translational Medicine 2017;6:2009-2019. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  12. [Musculature of the pelvic limb of the American weasel (Mustela nigripes, Audubon and Bachman)].

    PubMed

    Bisaillon, A

    1976-01-01

    The origins and insertions of the muscles of the pelvic limb of the black-footed ferret (Mustela nigripes) are illustrated and described. The results based on the dissection of two adult specimens are compared with those of other investigations on the myology of the Mustelids. The musculature of the pelvic limb of Mustela nigripes is substantially similar to that of other Mustelids investigated except for slight differences of individual muscles. The most obvious differences involve the tendons of the mm. fibularis longus, fibularis brevis and extensor digitalis lateralis. The tendon of the m. fibularis longus contains a small sesamoid bone.

  13. Tendon-Holding Capacities of Two Newly Designed Implants for Tendon Repair: An Experimental Study on the Flexor Digitorum Profundus Tendon of Sheep

    PubMed Central

    Ağır, İsmail; Aytekin, Mahmut Nedim; Başçı, Onur; Çaypınar, Barış; Erol, Bülent

    2014-01-01

    Background: Two main factors determine the strength of tendon repair; the tensile strength of material and the gripping capacity of a suture configuration. Different repair techniques and suture materials were developed to increase the strength of repairs but none of techniques and suture materials seem to provide enough tensile strength with safety margins for early active mobilization. In order to overcome this problem tendon suturing implants are being developed. We designed two different suturing implants. The aim of this study was to measure tendon-holding capacities of these implants biomechanically and to compare them with frequently used suture techniques Materials and Methods: In this study we used 64 sheep flexor digitorum profundus tendons. Four study groups were formed and each group had 16 tendons. We applied model 1 and model 2 implant to the first 2 groups and Bunnell and locking-loop techniques to the 3rd and 4th groups respectively by using 5 Ticron sutures. Results: In 13 tendons in group 1 and 15 tendons in group 2 and in all tendons in group 3 and 4, implants and sutures pulled out of the tendon in longitudinal axis at the point of maximum load. The mean tensile strengths were the largest in group 1 and smallest in group 3. Conclusion: In conclusion, the new stainless steel tendon suturing implants applied from outside the tendons using steel wires enable a biomechanically stronger repair with less tendon trauma when compared to previously developed tendon repair implants and the traditional suturing techniques. PMID:25067965

  14. [Clinical application of peroneal muscles tendon transposition in repair of Achilles tendon rupture].

    PubMed

    Jin, Rihao; Jin, Yu; Fang, Xiulin

    2006-07-01

    To discuss applied anatomy, biomechanics and surgical procedures of long peroneal muscles tendon transposition in repair of occlusive achilles tendon rupture. The blood supply and the morphology of long peroneal muscles tendon were observed in the lower extremity of 50 sides adult specimens and the mechanical tests which stretch load on the tendon were carried out. The methods were designed on the basis of the anatomical characteristics and morphology. Ten patients suffering occlusive Achilles tendon rupture were treated by using long peroneal muscles tendon transposition from March 2001 to July 2004. Among 10 patients, there were 7 males and 3 females, aging 32 to 54 years including 6 cases of jump injury, 2 cases of bruise, 1 case of step vacancy and 1 case of spontaneity injury. The interval between injury and surgery was 6 hours to 7 days in 7 fresh rupture and 21 days to 3 months in 3 old rupture. All cases belonged to occlusive Achilles tendon rupture (8 cases of complete rupture and 2 cases of incomplete rupture). The origin of long peroneal muscles was proximal tibia and fibular head, the end of them was base of first metatarsal bones and medial cuboid. The length of tendon was 13.5 +/- 2.5 cm. The width of origin tendon was 0.9 +/- 0.2 cm and the thickness was 0.3 +/- 0.1 cm; the width on apex of lateral malleolus was 0.7 +/- 0.1 cm and the thickness was 0.4 +/- 0.1 cm, the width on head of cuboid was 0.7 +/- 0.1 cm and the thickness was 0.3 +/- 0.1 cm. The long peroneal muscles tendon had abundant blood supply. The results of mechanical test showed that the biggest load was 2,292.4 +/- 617.3 N on tendon calcaneus, 1,020.4 +/- 175.4 N on long peroneal muscles tendon, 752.0 +/- 165.4 N on peroneus brevis tendon and 938.2 +/- 216.7 N on tibialis posterior tendon. Ten cases of occlusive Achilles tendon rupture achieved healing by first intention and were followed up 18-24 months. No Achilles tendon re-rupture, necrosis of skin or other complications occurred

  15. Tibial Lengthening: Extraarticular Calcaneotibial Screw to Prevent Ankle Equinus

    PubMed Central

    Belthur, Mohan V.; Paley, Dror; Jindal, Gaurav; Burghardt, Rolf D.; Specht, Stacy C.

    2008-01-01

    Between 2003 and 2006, we used an extraarticular, cannulated, fully threaded posterior calcaneotibial screw to prevent equinus contracture in 10 patients (four male and six female patients, 14 limbs) undergoing tibial lengthening with the intramedullary skeletal kinetic distractor. Diagnoses were fibular hemimelia (two), mesomelic dwarfism (two), posteromedial bow (one), hemihypertrophy (one), poliomyelitis (one), achondroplasia (one), posttraumatic limb-length discrepancy (one), and hypochondroplasia (one). Average age was 24.5 years (range, 15–54 years). The screw (length, typically 125 mm; diameter, 7 mm) was inserted with the ankle in 10° dorsiflexion. Gastrocnemius soleus recession was performed in two patients to achieve 10° dorsiflexion. Average lengthening was 4.9 cm (range, 3–7 cm). Screws were removed after a mean 3.3 months (range, 2–6 months). Preoperative ankle range of motion was regained within 6 months of screw removal. No neurovascular complications were encountered, and no patients experienced equinus contracture. We also conducted a cadaveric study in which one surgeon inserted screws in eight cadaveric legs under image intensifier control. The flexor hallucis longus muscle belly was the closest anatomic structure noted during dissection. The screw should be inserted obliquely from upper lateral edge of the calcaneus and aimed lateral in the tibia to avoid the flexor hallucis longus muscle. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18800215

  16. Tendon injuries of the hand

    PubMed Central

    Schöffl, Volker; Heid, Andreas; Küpper, Thomas

    2012-01-01

    Tendon injuries are the second most common injuries of the hand and therefore an important topic in trauma and orthopedic patients. Most injuries are open injuries to the flexor or extensor tendons, but less frequent injuries, e.g., damage to the functional system tendon sheath and pulley or dull avulsions, also need to be considered. After clinical examination, ultrasound and magnetic resonance imaging have proved to be important diagnostic tools. Tendon injuries mostly require surgical repair, dull avulsions of the distal phalanges extensor tendon can receive conservative therapy. Injuries of the flexor tendon sheath or single pulley injuries are treated conservatively and multiple pulley injuries receive surgical repair. In the postoperative course of flexor tendon injuries, the principle of early passive movement is important to trigger an “intrinsic” tendon healing to guarantee a good outcome. Many substances were evaluated to see if they improved tendon healing; however, little evidence was found. Nevertheless, hyaluronic acid may improve intrinsic tendon healing. PMID:22720265

  17. Peroneal tendon disorders

    PubMed Central

    Davda, Kinner; Malhotra, Karan; O’Donnell, Paul; Singh, Dishan; Cullen, Nicholas

    2017-01-01

    Pathological abnormality of the peroneal tendons is an under-appreciated source of lateral hindfoot pain and dysfunction that can be difficult to distinguish from lateral ankle ligament injuries. Enclosed within the lateral compartment of the leg, the peroneal tendons are the primary evertors of the foot and function as lateral ankle stabilisers. Pathology of the tendons falls into three broad categories: tendinitis and tenosynovitis, tendon subluxation and dislocation, and tendon splits and tears. These can be associated with ankle instability, hindfoot deformity and anomalous anatomy such as a low lying peroneus brevis or peroneus quartus. A thorough clinical examination should include an assessment of foot type (cavus or planovalgus), palpation of the peronei in the retromalleolar groove on resisted ankle dorsiflexion and eversion as well as testing of lateral ankle ligaments. Imaging including radiographs, ultrasound and MRI will help determine the diagnosis. Treatment recommendations for these disorders are primarily based on case series and expert opinion. The aim of this review is to summarise the current understanding of the anatomy and diagnostic evaluation of the peroneal tendons, and to present both conservative and operative management options of peroneal tendon lesions. Cite this article: EFORT Open Rev 2017;2:281-292. DOI: 10.1302/2058-5241.2.160047 PMID:28736620

  18. Peroneal tendon disorders.

    PubMed

    Davda, Kinner; Malhotra, Karan; O'Donnell, Paul; Singh, Dishan; Cullen, Nicholas

    2017-06-01

    Pathological abnormality of the peroneal tendons is an under-appreciated source of lateral hindfoot pain and dysfunction that can be difficult to distinguish from lateral ankle ligament injuries.Enclosed within the lateral compartment of the leg, the peroneal tendons are the primary evertors of the foot and function as lateral ankle stabilisers.Pathology of the tendons falls into three broad categories: tendinitis and tenosynovitis, tendon subluxation and dislocation, and tendon splits and tears. These can be associated with ankle instability, hindfoot deformity and anomalous anatomy such as a low lying peroneus brevis or peroneus quartus.A thorough clinical examination should include an assessment of foot type (cavus or planovalgus), palpation of the peronei in the retromalleolar groove on resisted ankle dorsiflexion and eversion as well as testing of lateral ankle ligaments.Imaging including radiographs, ultrasound and MRI will help determine the diagnosis. Treatment recommendations for these disorders are primarily based on case series and expert opinion.The aim of this review is to summarise the current understanding of the anatomy and diagnostic evaluation of the peroneal tendons, and to present both conservative and operative management options of peroneal tendon lesions. Cite this article: EFORT Open Rev 2017;2:281-292. DOI: 10.1302/2058-5241.2.160047.

  19. Functional tissue engineering of tendon: Establishing biological success criteria for improving tendon repair.

    PubMed

    Breidenbach, Andrew P; Gilday, Steven D; Lalley, Andrea L; Dyment, Nathaniel A; Gooch, Cynthia; Shearn, Jason T; Butler, David L

    2014-06-27

    Improving tendon repair using Functional Tissue Engineering (FTE) principles has been the focus of our laboratory over the last decade. Although our primary goals were initially focused only on mechanical outcomes, we are now carefully assessing the biological properties of our tissue-engineered tendon repairs so as to link biological influences with mechanics. However, given the complexities of tendon development and healing, it remains challenging to determine which aspects of tendon biology are the most important to focus on in the context of tissue engineering. To address this problem, we have formalized a strategy to identify, prioritize, and evaluate potential biological success criteria for tendon repair. We have defined numerous biological properties of normal tendon relative to cellular phenotype, extracellular matrix and tissue ultra-structure that we would like to reproduce in our tissue-engineered repairs and prioritized these biological criteria by examining their relative importance during both normal development and natural tendon healing. Here, we propose three specific biological criteria which we believe are essential for normal tendon function: (1) scleraxis-expressing cells; (2) well-organized and axially-aligned collagen fibrils having bimodal diameter distribution; and (3) a specialized tendon-to-bone insertion site. Moving forward, these biological success criteria will be used in conjunction with our already established mechanical success criteria to evaluate the effectiveness of our tissue-engineered tendon repairs. © 2013 Published by Elsevier Ltd.

  20. Tendon Mineralization Is Progressive and Associated with Deterioration of Tendon Biomechanical Properties, and Requires BMP-Smad Signaling in the Mouse Achilles Tendon Injury Model

    PubMed Central

    Zhang, Kairui; Asai, Shuji; Hast, Michael W.; Liu, Min; Usami, Yu; Iwamoto, Masahiro; Soslowsky, Louis J.; Enomoto-Iwamoto, Motomi

    2016-01-01

    Ectopic tendon mineralization can develop following tendon rupture or trauma surgery. The pathogenesis of ectopic tendon mineralization and its clinical impact have not been fully elucidated yet. In this study, we utilized a mouse Achilles tendon injury model to determine whether ectopic tendon mineralization alters the biomechanical properties of the tendon and whether BMP signaling is involved in this condition. A complete transverse incision was made at the midpoint of the right Achilles tendon in 8-week-old CD1 mice and the gap was left open. Ectopic cartilaginous mass formation was found in the injured tendon by 4 weeks post-surgery and ectopic mineralization was detected at 8–10 weeks post-surgery. Ectopic mineralization grew over time and volume of the mineralized materials of 25-weeks samples was about 2.5 fold bigger than that of 10-weeks samples, indicating that injury-induced ectopic tendon mineralization is progressive. In vitro mechanical testing showed that max force, max stress and mid-substance modulus in the 25-weeks samples were significantly lower than the 10-weeks samples. We observed substantial increases in expression of bone morphogenetic protein family genes in injured tendons 1 week post-surgery. Immunohistochemical analysis showed that phosphorylation of both Smad1 and Smad3 were highly increased in injured tendons as early as 1 week post-injury and remained high in ectopic chondrogenic lesions 4 weeks post-injury. Treatment with the BMP receptor kinase inhibitor (LDN193189) significantly inhibited injury-induced tendon mineralization. These findings indicate that injury-induced ectopic tendon mineralization is progressive, involves BMP signaling and associated with deterioration of tendon biomechanical properties. PMID:26825318

  1. Reversed Palmaris Longus Muscle Causing Volar Forearm Pain and Ulnar Nerve Paresthesia.

    PubMed

    Bhashyam, Abhiram R; Harper, Carl M; Iorio, Matthew L

    2017-04-01

    A case of volar forearm pain associated with ulnar nerve paresthesia caused by a reversed palmaris longus muscle is described. The patient, an otherwise healthy 46-year-old male laborer, presented after a previous unsuccessful forearm fasciotomy for complaints of exercise exacerbated pain affecting the volar forearm associated with paresthesia in the ulnar nerve distribution. A second decompressive fasciotomy was performed revealing an anomalous "reversed" palmaris longus, with the muscle belly located distally. Resection of the anomalous muscle was performed with full relief of pain and sensory symptoms. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  2. Achilles Tendonitis

    MedlinePlus

    ... almost impossible. Achilles tendonitis is a very common running injury. But it can also affect basketball players, dancers, ... Proximal Biceps Tendonitis Safety Tips: Basketball Safety Tips: Running Repetitive Stress Injuries Sports and Exercise Safety Dealing With Sports Injuries ...

  3. The effect of seprafilm on adhesion formation and tendon healing after flexor tendon repair in chicken.

    PubMed

    Yilmaz, Erhan; Avci, Mustafa; Bulut, Mehmet; Kelestimur, Halidun; Karakurt, Lokman; Ozercan, Ibrahim

    2010-03-01

    Adhesion of the tendon, which can occur during healing of tendon repair, is negatively affected by the outcome of surgery. In this experimental study, we sought to prevent adhesion of the tendon, and determined the mechanical stiffness of repair tissue by wrapping sodium hyaluronate and carboxymethylcellulose (Seprafilm; Genzyme, Cambridge, Massachusetts) around the repaired tendon segments. The study group comprised 2 groups of 20 chickens. In group I, the right gastrocnemius tendons of the chickens were cut smoothly, and after tendon and sheath repair, the skin was sutured. In group II, the right gastrocnemius tendons of the chickens were cut, the tendons were repaired, and before skin closure, Seprafilm was wrapped around the repaired tendon segments. Plastic splints were used for holding the chickens' ankles in a neutral position, and they were allowed weight bearing for 8 weeks. In group II, anatomic space between the tendon-sheath and tendon was clear and the tendon-sheath complex was sliding easily around the repaired tendon segment, and this complex was more functional both biomechanically and histologically. Also, the Seprafilm-applied tendons (group II) were observed to be biomechanically more resistant to the tensile forces in group I. Seprafilm is an easily applied interpositional material that can be used safely to prevent adhesion during the tendon healing process. Copyright 2010, SLACK Incorporated.

  4. Distal Biceps Tendon Rupture

    DTIC Science & Technology

    2010-06-01

    Distal Biceps Tendon Rupture Military Medicine Radiology Corner, 2006 Radiology Corner Distal Biceps Tendon Rupture Contributors: CPT Michael...treatment of a 56-year-old man with complete rupture of the distal biceps tendon . The mechanism of injury, symptoms, and findings at physical...be used in pre-operative planning. Introduction Rupture of the distal biceps tendon is a relatively uncommon injury, but delayed diagnosis may

  5. Tendon Functional Extracellular Matrix

    PubMed Central

    Screen, H.R.C.; Birk, D.E.; Kadler, K.E.; Ramirez, F; Young, M.F.

    2015-01-01

    This article is one of a series, summarising views expressed at the Orthopaedic Research Society New Frontiers in Tendon Research Conference. This particular article reviews the three workshops held under the “Functional Extracellular Matrix” stream. The workshops focused on the roles of the tendon extracellular matrix, such as performing the mechanical functions of tendon, creating the local cell environment and providing cellular cues. Tendon is a complex network of matrix and cells, and its biological functions are influenced by widely-varying extrinsic and intrinsic factors such as age, nutrition, exercise levels and biomechanics. Consequently, tendon adapts dynamically during development, ageing and injury. The workshop discussions identified research directions associated with understanding cell-matrix interactions to be of prime importance for developing novel strategies to target tendon healing or repair. PMID:25640030

  6. Therapeutics for tendon regeneration: a multidisciplinary review of tendon research for improved healing.

    PubMed

    Paredes, J J; Andarawis-Puri, Nelly

    2016-11-01

    Tendon injuries, known as tendinopathies, are common musculoskeletal injuries that affect a wide range of the population. Canonical tendon healing is characterized by fibrosis, scar formation, and the loss of tissue mechanical and structural properties. Understanding the regenerative tendon environment is an area of increasing interest in the field of musculoskeletal research. Previous studies have focused on utilizing individual elements from the fields of biomechanics, developmental biology, cell and growth factor therapy, and tissue engineering in an attempt to develop regenerative tendon therapeutics. Still, the specific mechanism for regenerative healing remains unknown. In this review, we highlight some of the current approaches of tendon therapeutics and elucidate the differences along the tendon midsubstance and enthesis, exhibiting the necessity of location-specific tendon therapeutics. Furthermore, we emphasize the necessity of further interdisciplinary research in order to reach the desired goal of fully understanding the mechanisms underlying regenerative healing. © 2016 New York Academy of Sciences.

  7. Neuronal regulation of tendon homoeostasis

    PubMed Central

    Ackermann, Paul W

    2013-01-01

    The regulation of tendon homoeostasis, including adaptation to loading, is still not fully understood. Accumulating data, however, demonstrates that in addition to afferent (sensory) functions, the nervous system, via efferent pathways which are associated with through specific neuronal mediators plays an active role in regulating pain, inflammation and tendon homeostasis. This neuronal regulation of intact-, healing- and tendinopathic tendons has been shown to be mediated by three major groups of molecules including opioid, autonomic and excitatory glutamatergic neuroregulators. In intact healthy tendons the neuromediators are found in the surrounding structures: paratenon, endotenon and epitenon, whereas the proper tendon itself is practically devoid of neurovascular supply. This neuroanatomy reflects that normal tendon homoeostasis is regulated from the tendon surroundings. After injury and during tendon repair, however, there is extensive nerve ingrowth into the tendon proper, followed by a time-dependent emergence of sensory, autonomic and glutamatergic mediators, which amplify and fine-tune inflammation and regulate tendon regeneration. In tendinopathic condition, excessive and protracted presence of sensory and glutamatergic neuromediators has been identified, suggesting involvement in inflammatory, nociceptive and hypertrophic (degenerative) tissue responses. Under experimental and clinical conditions of impaired (e.g. diabetes) as well as excessive (e.g. tendinopathy) neuromediator release, dysfunctional tendon homoeostasis develops resulting in chronic pain and gradual degeneration. Thus there is a prospect that in the future pharmacotherapy and tissue engineering approaches targeting neuronal mediators and their receptors may prove to be effective therapies for painful, degenerative and traumatic tendon disorders. PMID:23718724

  8. Angiopoietin‐like 4 promotes angiogenesis in the tendon and is increased in cyclically loaded tendon fibroblasts

    PubMed Central

    Mousavizadeh, Rouhollah; Scott, Alex; Lu, Alex; Ardekani, Gholamreza S; Behzad, Hayedeh; Lundgreen, Kirsten; Ghaffari, Mazyar; McCormack, Robert G

    2016-01-01

    Key points Angiopoietin‐like 4 (ANGPTL4) modulates tendon neovascularization.Cyclic loading stimulates the activity of transforming growth factor‐β and hypoxia‐inducible factor 1α and thereby increases the expression and release of ANGPTL4 from human tendon cells.Targeting ANGPTL4 and its regulatory pathways is a potential avenue for regulating tendon vascularization to improve tendon healing or adaptation. Abstract The mechanisms that regulate angiogenic activity in injured or mechanically loaded tendons are poorly understood. The present study examined the potential role of angiopoietin‐like 4 (ANGPTL4) in the angiogenic response of tendons subjected to repetitive mechanical loading or injury. Cyclic stretching of human tendon fibroblasts stimulated the expression and release of ANGPTL4 protein via transforming growth factor‐β (TGF‐β) and hypoxia‐inducible factor 1α (HIF‐1α) signalling, and the released ANGPTL4 was pro‐angiogenic. Angiogenic activity was increased following ANGPTL4 injection into mouse patellar tendons, whereas the patellar tendons of ANGPTL4 knockout mice displayed reduced angiogenesis following injury. In human rotator cuff tendons, the expression of ANGPTL4 was correlated with the density of tendon endothelial cells. To our knowledge, this is the first study characterizing a role of ANGPTL4 in the tendon. ANGPTL4 may assist in the regulation of vascularity in the injured or mechanically loaded tendon. TGF‐β and HIF‐1α comprise two signalling pathways that modulate the expression of ANGPTL4 by mechanically stimulated tendon fibroblasts and, in the future, these could be manipulated to influence tendon healing or adaptation. PMID:26670924

  9. How Obesity Affects Tendons?

    PubMed

    Abate, Michele; Salini, Vincenzo; Andia, Isabel

    Several epidemiological and clinical observations have definitely demonstrated that obesity has harmful effects on tendons. The pathogenesis of tendon damage is multi-factorial. In addition to overload, attributable to the increased body weight, which significantly affects load-bearing tendons, systemic factors play a relevant role. Several bioactive peptides (chemerin, leptin, adiponectin and others) are released by adipocytes, and influence tendon structure by means of negative activities on mesenchymal cells. The ensuing systemic state of chronic, sub-clinic, low-grade inflammation can damage tendon structure. Metabolic disorders (diabetes, impaired glucose tolerance, and dislipidemia), frequently associated with visceral adiposity, are concurrent pathogenetic factors. Indeed, high glucose levels increase the formation of Advanced Glycation End-products, which in turn form stable covalent cross-links within collagen fibers, modifying their structure and functionality.Sport activities, so useful for preventing important cardiovascular complications, may be detrimental for tendons if they are submitted to intense acute or chronic overload. Therefore, two caution rules are mandatory: first, to engage in personalized soft training program, and secondly to follow regular check-up for tendon pathology.

  10. Lubricin Surface Modification Improves Tendon Gliding After Tendon Repair in a Canine Model in Vitro

    PubMed Central

    Taguchi, Manabu; Sun, Yu-Long; Zhao, Chunfeng; Zobitz, Mark E.; Cha, Chung-Ja; Jay, Gregory D.; An, Kai-Nan; Amadio, Peter C.

    2011-01-01

    This study investigated the effects of lubricin on the gliding of repaired flexor digitorum profundus (FDP) tendons in vitro. Canine FDP tendons were completely lacerated, repaired with a modified Pennington technique, and treated with one of the following solutions: saline, carbodiimide derivatized gelatin/hyaluronic acid (cd-HA-gelatin), carbodiimide derivatized gelatin to which lubricin was added in a second step (cd-gelatin + lubricin), or carbodiimide derivatized gelatin/HA + lubricin (cd-HA-gelatin + lubricin). After treatment, gliding resistance was measured up to 1,000 cycles of simulated flexion/extension motion. The increase in average and peak gliding resistance in cd-HA-gelatin, cd-gelatin + lubricin, and cd-HA-gelatin + lubricin tendons was less than the control tendons after 1,000 cycles (p < 0.05). The increase in average gliding resistance of cd-HA-gelatin + lubricin treated tendons was also less than that of the cd-HA-gelatin treated tendons (p < 0.05). The surfaces of the repaired tendons and associated pulleys were assessed qualitatively with scanning electron microscopy and appeared smooth after 1,000 cycles of tendon motion for the cd-HA-gelatin, cd-gelatin + lubricin, and cd-HA-gelatin + lubricin treated tendons, while that of the saline control appeared roughened. These results suggest that tendon surface modification can improve tendon gliding ability, with a trend suggesting that lubricin fixed on the repaired tendon may provide additional improvement over that provided by HA and gelatin alone. PMID:18683890

  11. Angiopoietin-like 4 promotes angiogenesis in the tendon and is increased in cyclically loaded tendon fibroblasts.

    PubMed

    Mousavizadeh, Rouhollah; Scott, Alex; Lu, Alex; Ardekani, Gholamreza S; Behzad, Hayedeh; Lundgreen, Kirsten; Ghaffari, Mazyar; McCormack, Robert G; Duronio, Vincent

    2016-06-01

    Angiopoietin-like 4 (ANGPTL4) modulates tendon neovascularization. Cyclic loading stimulates the activity of transforming growth factor-β and hypoxia-inducible factor 1α and thereby increases the expression and release of ANGPTL4 from human tendon cells. Targeting ANGPTL4 and its regulatory pathways is a potential avenue for regulating tendon vascularization to improve tendon healing or adaptation. The mechanisms that regulate angiogenic activity in injured or mechanically loaded tendons are poorly understood. The present study examined the potential role of angiopoietin-like 4 (ANGPTL4) in the angiogenic response of tendons subjected to repetitive mechanical loading or injury. Cyclic stretching of human tendon fibroblasts stimulated the expression and release of ANGPTL4 protein via transforming growth factor-β (TGF-β) and hypoxia-inducible factor 1α (HIF-1α) signalling, and the released ANGPTL4 was pro-angiogenic. Angiogenic activity was increased following ANGPTL4 injection into mouse patellar tendons, whereas the patellar tendons of ANGPTL4 knockout mice displayed reduced angiogenesis following injury. In human rotator cuff tendons, the expression of ANGPTL4 was correlated with the density of tendon endothelial cells. To our knowledge, this is the first study characterizing a role of ANGPTL4 in the tendon. ANGPTL4 may assist in the regulation of vascularity in the injured or mechanically loaded tendon. TGF-β and HIF-1α comprise two signalling pathways that modulate the expression of ANGPTL4 by mechanically stimulated tendon fibroblasts and, in the future, these could be manipulated to influence tendon healing or adaptation. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

  12. Posterior Endoscopic Excision of Os Trigonum in Professional National Ballet Dancers.

    PubMed

    Ballal, Moez S; Roche, Andy; Brodrick, Anna; Williams, R Lloyd; Calder, James D F

    2016-01-01

    Previous studies have compared the outcomes after open and endoscopic excision of an os trigonum in patients of mixed professions. No studies have compared the differences in outcomes between the 2 procedures in elite ballet dancers. From October 2005 to February 2010, 35 professional ballet dancers underwent excision of a symptomatic os trigonum of the ankle after a failed period of nonoperative treatment. Of the 35 patients, 13 (37.1%) underwent endoscopic excision and 22 (62.9%) open excision. We compared the outcomes, complications, and time to return to dancing. The open excision group experienced a significantly greater incidence of flexor hallucis longus tendon decompression compared with the endoscopic group. The endoscopic release group returned to full dance earlier at a mean of 9.8 (range 6.5 to 16.1) weeks and those undergoing open excision returned to full dance at a mean of 14.9 (range 9 to 20) weeks (p = .001). No major complications developed in either group, such as deep infection or nerve or vessel injury. We have concluded that both techniques are safe and effective in the treatment of symptomatic os trigonum in professional ballet dancers. Endoscopic excision of the os trigonum offers a more rapid return to full dance compared with open excision. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  13. [Achilles tendon rupture].

    PubMed

    Thermann, H; Hüfner, T; Tscherne, H

    2000-03-01

    The treatment of acute of Achilles tendon rupture experienced a dynamic development in the last ten years. Decisive for this development was the application of MRI and above all the ultrasonography in the diagnostics of the pathological changes and injuries of tendons. The question of rupture morphology as well as different courses of healing could be now evaluated objectively. These advances led consequently to new modalities in treatment concepts and rehabilitation protocols. The decisive input for improvements of the outcome results and particularly the shortening of the rehabilitation period came with introduction of the early functional treatment in contrast to immobilizing plaster treatment. In a prospective randomized study (1987-1989) at the Trauma Dept. of the Hannover Medical School could show no statistical differences comparing functional non-operative with functional operative therapy with a special therapy boot (Variostabil/Adidas). The crucial criteria for therapy selection results from the sonographically measured position of the tendon stumps in plantar flexion (20 degrees). With complete adaptation of the tendons' ends surgical treatment does not achieve better results than non-operative functional treatment in term of tendon healing and functional outcome. Regarding the current therapeutic standards each method has is advantages and disadvantages. Both, the operative and non-operative functional treatment enable a stable tendon healing with a low risk of re-rupture (1-2%). Meanwhile there is consensus for early functional after-treatment of the operated Achilles' tendons. There seems to be a trend towards non-operative functional treatment in cases of adequate sonographical findings, or to minimal invasive surgical techniques.

  14. Assessment of Postoperative Tendon Quality in Patients With Achilles Tendon Rupture Using Diffusion Tensor Imaging and Tendon Fiber Tracking.

    PubMed

    Sarman, Hakan; Atmaca, Halil; Cakir, Ozgur; Muezzinoglu, Umit Sefa; Anik, Yonca; Memisoglu, Kaya; Baran, Tuncay; Isik, Cengiz

    2015-01-01

    Although pre- and postoperative imaging of Achilles tendon rupture (ATR) has been well documented, radiographic evaluations of postoperative intratendinous healing and microstructure are still lacking. Diffusion tensor imaging (DTI) is an innovative technique that offers a noninvasive method for describing the microstructure characteristics and organization of tissues. DTI was used in the present study for quantitative assessment of fiber continuity postoperatively in patients with acute ATR. The data from 16 patients with ATR from 2005 to 2012 were retrospectively analyzed. The microstructure of ART was evaluated using tendon fiber tracking, tendon continuity, fractional anisotropy, and apparent diffusion coefficient values by way of DTI. The distal and proximal portions were measured separately in both the ruptured and the healthy extremities of each patient. The mean patient age was 41.56 ± 8.49 (range 26 to 56) years. The median duration of follow-up was 21 (range 6 to 80) months. The tendon fractional anisotropy values of the ruptured Achilles tendon were significantly lower statistically than those of the normal side (p = .001). However, none of the differences between the 2 groups with respect to the distal and proximal apparent diffusion coefficient were statistically significant (p = .358 and p = .899, respectively). In addition, the fractional anisotropy and apparent diffusion coefficient measurements were not significantly different in the proximal and distal regions of the ruptured tendons compared with the healthy tendons. The present study used DTI and fiber tracking to demonstrate the radiologic properties of postoperative Achilles tendons with respect to trajectory and tendinous fiber continuity. Quantifying DTI and fiber tractography offers an innovative and effective tool that might be able to detect microstructural abnormalities not appreciable using conventional radiologic techniques. Copyright © 2015 American College of Foot and Ankle

  15. [Rupture of the Achilles tendon].

    PubMed

    Ulmar, B; Simon, S; Eschler, A; Mittlmeier, T

    2014-10-01

    The rupture of the Achilles tendon is the most frequent tendon rupture in humans and it is associated with increasing incidence. The main risk factor is intrinsic degeneration of the tendon. During the rupture the person feels a whiplash or dagger thrust-like pain, followed by restricted walking ability and decreased plantar flexion of the ankle. The positive Simmond/Thompson test and a palpable dent above the tendon rupture are pathognomical. Diagnostically, ultrasound of the tendon and lateral x-ray of the calcaneus (bony pull-out of the tendon insertion) are necessary. Regarding correct indication and treatment modalities, most established conservative and surgical therapies realize optimal functional results. Surgical treatment promises better primary stability and slightly earlier better functional results, but there is the potential for surgical complications. Conservative therapy is associated with higher rates of re-rupture and healing of the tendon under elongation. Therefore, therapy planning in Achilles tendon rupture should be determined based on each patient. We recommend surgical treatment in patients with higher sporting demands and in younger patients (< 50 years).

  16. Tendon elasticity and muscle function.

    PubMed

    Alexander, R McNeill

    2002-12-01

    Vertebrate animals exploit the elastic properties of their tendons in several different ways. Firstly, metabolic energy can be saved in locomotion if tendons stretch and then recoil, storing and returning elastic strain energy, as the animal loses and regains kinetic energy. Leg tendons save energy in this way when birds and mammals run, and an aponeurosis in the back is also important in galloping mammals. Tendons may have similar energy-saving roles in other modes of locomotion, for example in cetacean swimming. Secondly, tendons can recoil elastically much faster than muscles can shorten, enabling animals to jump further than they otherwise could. Thirdly, tendon elasticity affects the control of muscles, enhancing force control at the expense of position control.

  17. Fatigue loading of tendon

    PubMed Central

    Shepherd, Jennifer H; Screen, Hazel R C

    2013-01-01

    Tendon injuries, often called tendinopathies, are debilitating and painful conditions, generally considered to develop as a result of tendon overuse. The aetiology of tendinopathy remains poorly understood, and whilst tendon biopsies have provided some information concerning tendon appearance in late-stage disease, there is still little information concerning the mechanical and cellular events associated with disease initiation and progression. Investigating this in situ is challenging, and numerous models have been developed to investigate how overuse may generate tendon fatigue damage and how this may relate to tendinopathy conditions. This article aims to review these models and our current understanding of tendon fatigue damage. We review the strengths and limitations of different methodologies for characterizing tendon fatigue, considering in vitro methods that adopt both viable and non-viable samples, as well as the range of different in vivo approaches. By comparing data across model systems, we review the current understanding of fatigue damage development. Additionally, we compare these findings with data from tendinopathic tissue biopsies to provide some insights into how these models may relate to the aetiology of tendinopathy. Fatigue-induced damage consistently highlights the same microstructural, biological and mechanical changes to the tendon across all model systems and also correlates well with the findings from tendinopathic biopsy tissue. The multiple testing routes support matrix damage as an important contributor to tendinopathic conditions, but cellular responses to fatigue appear complex and often contradictory. PMID:23837793

  18. Tendon 'turnover lengthening' technique.

    PubMed

    Cerovac, S; Miranda, B H

    2013-11-01

    Tendon defect reconstruction is amongst the most technically challenging areas in hand surgery. Tendon substance deficiency reconstruction techniques include lengthening, grafting, two-stage reconstruction and tendon transfers, however each is associated with unique challenges over and above direct repair. We describe a novel 'turnover lengthening' technique for hand tendons that has successfully been applied to the repair of several cases, including a case of attritional flexor and traumatic extensor tendon rupture in two presented patients where primary tenorrhaphy was not possible. In both cases a good post-operative outcome was achieved, as the patients were happy having returned back to normal activities of daily living such that they were discharged 12 weeks post-operatively. Our technique avoids the additional morbidity and complications associated with grafting, transfers and two stage reconstructions. It is quick, simple and reproducible for defects not exceeding 3-4 cm, provides a means of immediate one stage reconstruction, no secondary donor site morbidity and does not compromise salvage by tendon transfer and/or two-stage reconstruction in cases of failure. To our knowledge no such technique has been previously been described to reconstruct such hand tendon defects. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  19. Determining physiological cross-sectional area of extensor carpi radialis longus and brevis as a whole and by regions using 3D computer muscle models created from digitized fiber bundle data.

    PubMed

    Ravichandiran, Kajeandra; Ravichandiran, Mayoorendra; Oliver, Michele L; Singh, Karan S; McKee, Nancy H; Agur, Anne M R

    2009-09-01

    Architectural parameters and physiological cross-sectional area (PCSA) are important determinants of muscle function. Extensor carpi radialis longus (ECRL) and brevis (ECRB) are used in muscle transfers; however, their regional architectural differences have not been investigated. The aim of this study is to develop computational algorithms to quantify and compare architectural parameters (fiber bundle length, pennation angle, and volume) and PCSA of ECRL and ECRB. Fiber bundles distributed throughout the volume of ECRL (75+/-20) and ECRB (110+/-30) were digitized in eight formalin embalmed cadaveric specimens. The digitized data was reconstructed in Autodesk Maya with computational algorithms implemented in Python. The mean PCSA and fiber bundle length were significantly different between ECRL and ECRB (p < or = 0.05). Superficial ECRL had significantly longer fiber bundle length than the deep region, whereas the PCSA of superficial ECRB was significantly larger than the deep region. The regional quantification of architectural parameters and PCSA provides a framework for the exploration of partial tendon transfers of ECRL and ECRB.

  20. Scaffolds in Tendon Tissue Engineering

    PubMed Central

    Longo, Umile Giuseppe; Lamberti, Alfredo; Petrillo, Stefano; Maffulli, Nicola; Denaro, Vincenzo

    2012-01-01

    Tissue engineering techniques using novel scaffold materials offer potential alternatives for managing tendon disorders. Tissue engineering strategies to improve tendon repair healing include the use of scaffolds, growth factors, cell seeding, or a combination of these approaches. Scaffolds have been the most common strategy investigated to date. Available scaffolds for tendon repair include both biological scaffolds, obtained from mammalian tissues, and synthetic scaffolds, manufactured from chemical compounds. Preliminary studies support the idea that scaffolds can provide an alternative for tendon augmentation with an enormous therapeutic potential. However, available data are lacking to allow definitive conclusion on the use of scaffolds for tendon augmentation. We review the current basic science and clinical understanding in the field of scaffolds and tissue engineering for tendon repair. PMID:22190961

  1. Tendon and ligament imaging

    PubMed Central

    Hodgson, R J; O'Connor, P J; Grainger, A J

    2012-01-01

    MRI and ultrasound are now widely used for the assessment of tendon and ligament abnormalities. Healthy tendons and ligaments contain high levels of collagen with a structured orientation, which gives rise to their characteristic normal imaging appearances as well as causing particular imaging artefacts. Changes to ligaments and tendons as a result of disease and injury can be demonstrated using both ultrasound and MRI. These have been validated against surgical and histological findings. Novel imaging techniques are being developed that may improve the ability of MRI and ultrasound to assess tendon and ligament disease. PMID:22553301

  2. Mechanical Strength of the Side-to-Side Tendon Attachment for Mismatched Tendon Sizes and Shapes

    PubMed Central

    Fridén, Jan; Tirrell, Timothy F.; Bhola, Siddharth; Lieber, Richard L.

    2015-01-01

    Summary Certain combinations are advised against in tendon transfers due to size or shape mismatches between donor and recipient tendons. In this study, ultimate load, stiffness and Young’s modulus were measured in two tendon-to-tendon attachments with intentionally mismatched donor and recipient tendons - pronator teres (PT)-to-extensor carpi radialis brevis (ECRB) and flexor carpi ulnaris (FCU)-to-extensor digitorum communis (EDC). FCU-EDC attachments failed at higher loads than PT-to-ECRB attachments but they had similar modulus and stiffness values. Ultimate tensile strength of the tendon attachments exceeded the maximum predicted contraction force of any of the affected muscles, with safety factors of 4x and 2x for the FCU-to-EDC and PT-to-ECRB constructs, respectively. This implies that size and shape mismatch should not be a contraindication to tendon attachment in transfers. Further, these safety factors strongly suggest that no postoperative immobilization of these attachments is necessary. PMID:24413573

  3. Does the longus colli have an effect on cervical vertigo?: A retrospective study of 116 patients.

    PubMed

    Liu, Xiao-Ming; Pan, Fu-Min; Yong, Zhi-Yao; Ba, Zhao-Yu; Wang, Shan-Jin; Liu, Zheng; Zhao, Wei-Dong; Wu, De-Sheng

    2017-03-01

    The aim of the study was to evaluate the role of the longus colli muscles in cervical vertigo.We retrospectively analyzed 116 adult patients who underwent anterior cervical discectomy and fusion (ACDF) during 2014 in our department. Patients were assigned to the vertigo group or the nonvertigo group. Demographic data were recorded. Inner distance and cross-sectional area (CSA) of longus colli were measured using coronal magnetic resonance imaging (MRI).The vertigo group (n = 44) and the nonvertigo group (n = 72) were similar in demographic data. Mean preoperative Japanese Orthopaedic Association (JOA) score was higher in the vertigo group than in the nonvertigo group (P = 0.037), but no difference postoperatively. Mean JOA scores increased significantly postoperatively in both groups (P = 0.002 and P = 0.001). The mean vertigo score decreased significantly from pre- to postoperatively in the vertigo group (P = 0.023). The mean preoperative Cobb angle was significantly smaller in the vertigo group than in the nonvertigo group (P <0.001), but no significant difference postoperatively. After ACDF, the mean Cobb angle increased significantly in the vertigo group (P <0.001). The instability rates of C3/4 and C4/5 were significantly higher in the vertigo group (P <0.001 and P <0.001). The inner distance of longus colli was significantly shorter (P = 0.032 and P = 0.026) and CSA significantly smaller (P = 0.041 and P = 0.035), at C3/4 and C4/5 in the vertigo group than in the nonvertigo group. Mean Miyazaki scores were significantly higher in the vertigo group at C3/4 and C4/5 (P = 0.044 and P = 0.037). Moreover, a shorter inner distance and smaller CSA were related to a higher Miyazaki score.Inner distance and cross-sectional area (CSA) of longus colli are associated closely with cervical vertigo. Shorter inner distance and smaller CSA of the longus colli muscles might be risk factors for cervical vertigo. ACDF provided a

  4. Histochemical and morphometric characteristics of the normal human vastus medialis longus and vastus medialis obliquus muscles.

    PubMed Central

    Travnik, L; Pernus, F; Erzen, I

    1995-01-01

    The histochemical and morphometric characteristics of the vastus medialis longus and vastus medialis obliquus muscles were studied and compared with data on vastus lateralis. Cross-sections of autopsied muscles from 9 healthy men, aged 18-44 y, who had died suddenly were analysed. Data were obtained on proportions, cross-sectional diameter, and on atrophy and hypertrophy factors, of type 1, 2a, 2b, and 2c fibres. The analysis showed that the anatomical differences and the different functional demands placed on vastus medialis longus and vastus medialis obliquus are also expressed in different proportions and sizes of fibre types in the two muscles. The proportion of type 1 fibres was significantly higher (P < 0.01), and the proportion of 2b fibres was significantly lower (P < 0.01) in vastus medialis longus than in vastus medialis obliquus. The diameters of type 1 and type 2a fibres were significantly smaller (P < 0.01) in vastus medialis longus than in vastus medialis obliquus, although the differences were small. Within muscles a nonrandom arrangement of fibre types existed with the deeper portions of the muscles having more type 1 fibres than the more superficial portions. The histochemical and morphometric characteristics of vastus lateralis and vastus medialis obliquus show great similarity, reflecting the common function of both muscles which is taking part in transverse knee stability. Estimates of the limits of normality of the proportion, diameter, atrophy and hypertrophy factors of type 1, 2a, 2b, and 2c fibres might be useful in obtaining information on how different physiological and pathological conditions influence the proportion and size of different fibre types.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7592003

  5. Bilateral Patellar Tendon Rupture

    DTIC Science & Technology

    2009-07-01

    Bilateral patellar tendon rupture Military Medicine Radiology Corner, Volume 173, July, 2009...Radiology Corner Bilateral patellar tendon rupture (#37) Guarantor: 2dLt Ramon A. Riojas, USAF, MSC1 Contributors: 2dLt Ramon A. Riojas...with the abbreviated answer in the July 2009 issue. 1 The authors present a case of bilateral patellar tendon rupture in an active duty male exiting

  6. The expression of Longus type 4 pilus of enterotoxigenic Escherichia coli is regulated by LngR and LngS and by H-NS, CpxR and CRP global regulators.

    PubMed

    De la Cruz, Miguel A; Ruiz-Tagle, Alejandro; Ares, Miguel A; Pacheco, Sabino; Yáñez, Jorge A; Cedillo, Lilia; Torres, Javier; Girón, Jorge A

    2017-05-01

    Enterotoxigenic Escherichia coli produces a long type 4 pilus called Longus. The regulatory elements and the environmental signals controlling the expression of Longus-encoding genes are unknown. We identified two genes lngR and lngS in the Longus operon, whose predicted products share homology with transcriptional regulators. Isogenic lngR and lngS mutants were considerably affected in transcription of lngA pilin gene. The expression of lngA, lngR and lngS genes was optimally expressed at 37°C at pH 7.5. The presence of glucose and sodium chloride had a positive effect on Longus expression. The presence of divalent ions, particularly calcium, appears to be an important stimulus for Longus production. In addition, we studied H-NS, CpxR and CRP global regulators, on Longus expression. The response regulator CpxR appears to function as a positive regulator of lng genes as the cpxR mutant showed reduced levels of lngRSA expression. In contrast, H-NS and CRP function as negative regulators since expression of lngA was up-regulated in isogenic hns and crp mutants. H-NS and CRP were required for salt- and glucose-mediated regulation of Longus. Our data suggest the existence of a complex regulatory network controlling Longus expression, involving both local and global regulators in response to different environmental signals. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  7. Optimization of human tendon tissue engineering: peracetic acid oxidation for enhanced reseeding of acellularized intrasynovial tendon.

    PubMed

    Woon, Colin Y L; Pridgen, Brian C; Kraus, Armin; Bari, Sina; Pham, Hung; Chang, James

    2011-03-01

    Tissue engineering of human flexor tendons combines tendon scaffolds with recipient cells to create complete cell-tendon constructs. Allogenic acellularized human flexor tendon has been shown to be a useful natural scaffold. However, there is difficulty repopulating acellularized tendon with recipient cells, as cell penetration is restricted by a tightly woven tendon matrix. The authors evaluated peracetic acid treatment in optimizing intratendinous cell penetration. Cadaveric human flexor tendons were harvested, acellularized, and divided into experimental groups. These groups were treated with peracetic acid in varying concentrations (2%, 5%, and 10%) and for varying time periods (4 and 20 hours) to determine the optimal treatment protocol. Experimental tendons were analyzed for differences in tendon microarchitecture. Additional specimens were reseeded by incubation in a fibroblast cell suspension at 1 × 10(6) cells/ml. This group was then analyzed for reseeding efficacy. A final group underwent biomechanical studies for strength. The optimal treatment protocol comprising peracetic acid at 5% concentration for 4 hours produced increased scaffold porosity, improving cell penetration and migration. Treated scaffolds did not show reduced collagen or glycosaminoglycan content compared with controls (p = 0.37 and p = 0.65, respectively). Treated scaffolds were cytotoxic to neither attached cells nor the surrounding cell suspension. Treated scaffolds also did not show inferior ultimate tensile stress or elastic modulus compared with controls (p = 0.26 and p = 0.28, respectively). Peracetic acid treatment of acellularized tendon scaffolds increases matrix porosity, leading to greater reseeding. It may prove to be an important step in tissue engineering of human flexor tendon using natural scaffolds.

  8. The distal biceps tendon.

    PubMed

    Schmidt, Christopher C; Jarrett, Claudius D; Brown, Brandon T

    2013-04-01

    Distal biceps tendon ruptures continue to be an important injury seen and treated by upper extremity surgeons. Since the mid-1980s, the emphasis has been placed on techniques that limit complications or improve initial tendon-to-bone fixation strength. Recently, basic science research has expanded the knowledge base regarding the biceps tendon structure, footprint anatomy, and biomechanics. Clinical data have further delineated the results of conservative and surgical management of both partial and complete tears in acute or chronic states. The current literature on the distal biceps tendon is described in detail. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  9. Tendon Driven Finger Actuation System

    NASA Technical Reports Server (NTRS)

    Ihrke, Chris A. (Inventor); Reich, David M. (Inventor); Bridgwater, Lyndon (Inventor); Linn, Douglas Martin (Inventor); Askew, Scott R. (Inventor); Diftler, Myron A. (Inventor); Platt, Robert (Inventor); Hargrave, Brian (Inventor); Valvo, Michael C. (Inventor); Abdallah, Muhammad E. (Inventor); hide

    2013-01-01

    A humanoid robot includes a robotic hand having at least one finger. An actuation system for the robotic finger includes an actuator assembly which is supported by the robot and is spaced apart from the finger. A tendon extends from the actuator assembly to the at least one finger and ends in a tendon terminator. The actuator assembly is operable to actuate the tendon to move the tendon terminator and, thus, the finger.

  10. Changes in Achilles tendon mechanical properties following eccentric heel drop exercise are specific to the free tendon.

    PubMed

    Obst, S J; Newsham-West, R; Barrett, R S

    2016-04-01

    Mechanical loading of the Achilles tendon during isolated eccentric contractions could induce immediate and region-dependent changes in mechanical properties. Three-dimensional ultrasound was used to examine the immediate effect of isolated eccentric exercise on the mechanical properties of the distal (free tendon) and proximal (gastrocnemii) regions of the Achilles tendon. Participants (n = 14) underwent two testing sessions in which tendon measurements were made at rest and during a 30% and 70% isometric plantar flexion contractions immediately before and after either: (a) 3 × 15 eccentric heel drops or (b) 10-min rest. There was a significant time-by-session interaction for free tendon length and strain for all loading conditions (P < 0.05). Pairwise comparisons revealed a significant increase in free tendon length and strain at all contraction intensities after eccentric exercise (P < 0.05). There was no significant time-by-session interaction for the gastrocnemii (medial or lateral) aponeurosis or tendon for any of the measured parameters. Immediate changes in Achilles tendon mechanical properties were specific to the free tendon and consistent with changes due to mechanical creep. These findings suggest that the mechanical properties of the free tendon may be more vulnerable to change with exercise compared with the gastrocnemii aponeurosis or tendon. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Mechanisms of tendon injury and repair

    PubMed Central

    Thomopoulos, Stavros; Parks, William C.; Rifkin, Daniel B.; Derwin, Kathleen A.

    2015-01-01

    Tendon disorders are common and lead to significant disability, pain, healthcare cost, and lost productivity. A wide range of injury mechanisms exist leading to tendinopathy or tendon rupture. Tears can occur in healthy tendons that are acutely overloaded (e.g., during a high speed or high impact event) or lacerated (e.g., a knife injury). Tendinitis or tendinosis can occur in tendons exposed to overuse conditions (e.g., an elite swimmer’s training regimen) or intrinsic tissue degeneration (e.g., age-related degeneration). The healing potential of a torn or pathologic tendon varies depending on anatomic location (e.g., Achilles vs. rotator cuff) and local environment (e.g., intrasynovial vs. extrasynovial). Although healing occurs to varying degrees, in general healing of repaired tendons follows the typical wound healing course, including an early inflammatory phase, followed by proliferative and remodeling phases. Numerous treatment approaches have been attempted to improve tendon healing, including growth factor- and cell-based therapies and rehabilitation protocols. This review will describe the current state of knowledge of injury and repair of the three most common tendinopathies-- flexor tendon lacerations, Achilles tendon rupture, and rotator cuff disorders-- with a particular focus on the use of animal models for understanding tendon healing. PMID:25641114

  12. Magnetotherapy: The quest for tendon regeneration.

    PubMed

    Pesqueira, Tamagno; Costa-Almeida, Raquel; Gomes, Manuela E

    2018-05-09

    Tendons are mechanosensitive tissues that connect and transmit the forces generated by muscles to bones by allowing the conversion of mechanical input into biochemical signals. These physical forces perform the fundamental work of preserving tendon homeostasis assuring body movements. However, overloading causes tissue injuries, which leads us to the field of tendon regeneration. Recently published reviews have broadly shown the use of biomaterials and different strategies to attain tendon regeneration. In this review, our focus is the use of magnetic fields as an alternative therapy, which has demonstrated clinical relevance in tendon medicine because of their ability to modulate cell fate. Yet the underlying cellular and molecular mechanisms still need to be elucidated. While providing a brief outlook about specific signalling pathways and intracellular messengers as framework in play by tendon cells, application of magnetic fields as a subcategory of physical forces is explored, opening up a compelling avenue to enhance tendon regeneration. We outline here useful insights on the effects of magnetic fields both at in vitro and in vivo levels, particularly on the expression of tendon genes and inflammatory cytokines, ultimately involved in tendon regeneration. Subsequently, the potential of using magnetically responsive biomaterials in tendon tissue engineering is highlighted and future directions in magnetotherapy are discussed. © 2018 Wiley Periodicals, Inc.

  13. Experimental evaluation of multiscale tendon mechanics.

    PubMed

    Fang, Fei; Lake, Spencer P

    2017-07-01

    Tendon's primary function is a mechanical link between muscle and bone. The hierarchical structure of tendon and specific compositional constituents are believed to be critical for proper mechanical function. With increased appreciation for tendon importance and the development of various technological advances, this review paper summarizes recent experimental approaches that have been used to study multiscale tendon mechanics, includes an overview of studies that have evaluated the role of specific tissue constituents, and also proposes challenges/opportunities facing tendon study. Tendon has been demonstrated to have specific structural characteristics (e.g., multi-level hierarchy, crimp pattern, helix) and complex mechanical properties (e.g., non-linearity, anisotropy, viscoelasticity). Physical mechanisms including uncrimping, fiber sliding, and collagen reorganization have been shown to govern tendon mechanical responses under both static and dynamic loading. Several tendon constituents with relatively small quantities have been suggested to play a role in its mechanics, although some results are conflicting. Further research should be performed to understand the interplay and communication of tendon mechanical properties across levels of the hierarchical structure, and further show how each of these components contribute to tendon mechanics. The studies summarized and discussed in this review have helped elucidate important aspects of multiscale tendon mechanics, which is a prerequisite for analyzing stress/strain transfer between multiple scales and identifying key principles of mechanotransduction. This information could further facilitate interpreting the functional diversity of tendons from different species, different locations, and even different developmental stages, and then better understand and identify fundamental concepts related to tendon degeneration, disease, and healing. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc

  14. Achilles Tendon Rupture

    MedlinePlus

    ... also help the muscle and tendon absorb more force and prevent injury. Vary your exercises. Alternate high-impact sports, such as running, with low-impact sports, such as walking, biking or swimming. Avoid activities that place excessive stress on your Achilles tendons, such as hill ...

  15. Collagen fibrils in functionally distinct tendons have differing structural responses to tendon rupture and fatigue loading.

    PubMed

    Herod, Tyler W; Chambers, Neil C; Veres, Samuel P

    2016-09-15

    In this study we investigate relationships between the nanoscale structure of collagen fibrils and the macroscale functional response of collagenous tissues. To do so, we study two functionally distinct classes of tendons, positional tendons and energy storing tendons, using a bovine forelimb model. Molecular-level assessment using differential scanning calorimetry (DSC), functional crosslink assessment using hydrothermal isometric tension (HIT) analysis, and ultrastructural assessment using scanning electron microscopy (SEM) were used to study undamaged, ruptured, and cyclically loaded samples from the two tendon types. HIT indicated differences in both crosslink type and crosslink density, with flexor tendons having more thermally stable crosslinks than the extensor tendons (higher TFmax of >90 vs. 75.1±2.7°C), and greater total crosslink density than the extensor tendons (higher t1/2 of 11.5±1.9 vs. 3.5±1.0h after NaBH4 treatment). Despite having a lower crosslink density than flexor tendons, extensor tendons were significantly stronger (37.6±8.1 vs. 23.1±7.7MPa) and tougher (14.3±3.6 vs. 6.8±3.4MJ/m(3)). SEM showed that collagen fibrils in the tougher, stronger extensor tendons were able to undergo remarkable levels of plastic deformation in the form of discrete plasticity, while those in the flexor tendons were not able to plastically deform. When cyclically loaded, collagen fibrils in extensor tendons accumulated fatigue damage rapidly in the form of kink bands, while those in flexor tendons did not accumulate significant fatigue damage. The results demonstrate that collagen fibrils in functionally distinct tendons respond differently to mechanical loading, and suggests that fibrillar collagens may be subject to a strength vs. fatigue resistance tradeoff. Collagen fibrils-nanoscale biological cables-are the fundamental load-bearing elements of all structural human tissues. While all collagen fibrils share common features, such as being composed of a

  16. Bioreactor design for tendon/ligament engineering.

    PubMed

    Wang, Tao; Gardiner, Bruce S; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B; Wang, Allan; Xu, Jiake; Smith, David W; Lloyd, David G; Zheng, Ming H

    2013-04-01

    Tendon and ligament injury is a worldwide health problem, but the treatment options remain limited. Tendon and ligament engineering might provide an alternative tissue source for the surgical replacement of injured tendon. A bioreactor provides a controllable environment enabling the systematic study of specific biological, biochemical, and biomechanical requirements to design and manufacture engineered tendon/ligament tissue. Furthermore, the tendon/ligament bioreactor system can provide a suitable culture environment, which mimics the dynamics of the in vivo environment for tendon/ligament maturation. For clinical settings, bioreactors also have the advantages of less-contamination risk, high reproducibility of cell propagation by minimizing manual operation, and a consistent end product. In this review, we identify the key components, design preferences, and criteria that are required for the development of an ideal bioreactor for engineering tendons and ligaments.

  17. Effect of tendon tensioning: an in vitro study in porcine extensor tendons.

    PubMed

    Figueroa, David; Calvo, Rafael; Vaisman, Alex; Meleán, Patricio; Figueroa, Francisco

    2010-06-01

    Graft tensioning is a controversial issue in anterior cruciate ligament reconstruction (ACLR) that has not achieved consensus between peers. The purpose of this study is to determine if after tensioning tendon length and resistance to maximal load changes. We performed an in vitro study with 50 porcine extensors tendons. The first group (P=25) was tensioned with 80 N (19.97 lb) for 10 min, using an ACL graft preparation board. The second group (C=25) was used as control and was not tensioned. The average initial (groups P and C) and post tensioning tendon length (group C) were measured; the average initial and post tensioning tendon diameter were measured as well. All samples were fixated in a tube-clamp system connected to a tension sensor. The samples were stressed with continuous and progressive tension until ultimate failure at maximum load (UFML) occurs. The initial mean length was: P before tensioning=13.4 mm+/-1.4 mm (range 10.5-16.5); P after tensioning=13.8 mm+/-1.4 mm (range 11.5-16.5); C=13 mm+/-1.35 mm (p=0.005). The mean diameter was: P=5.6 mm (4.5-6); C=5.5 mm (range 4.5-6) (p>0.05). The UFML was: P=189.7 N (114-336); C=229.9 N (143-365) (p=0.029). Tendon tensioning with 80 N for 10 min produced 3% average elongation. These could be beneficial in ACLR since tendon tensioning decreases elongation of the graft after fixation. Regardless, tendon tensioning is not innocuous since it diminishes their resistance when continuously stressed until complete failure occurs.

  18. Structure-function relationships in tendons: a review

    PubMed Central

    Benjamin, M; Kaiser, E; Milz, S

    2008-01-01

    The purpose of the current review is to highlight the structure-function relationship of tendons and related structures to provide an overview for readers whose interest in tendons needs to be underpinned by anatomy. Because of the availability of several recent reviews on tendon development and entheses, the focus of the current work is primarily directed towards what can best be described as the ‘tendon proper’ or the ‘mid-substance’ of tendons. The review covers all levels of tendon structure from the molecular to the gross and deals both with the extracellular matrix and with tendon cells. The latter are often called ‘tenocytes’ and are increasingly recognized as a defined cell population that is functionally and phenotypically distinct from other fibroblast-like cells. This is illustrated by their response to different types of mechanical stress. However, it is not only tendon cells, but tendons as a whole that exhibit distinct structure-function relationships geared to the changing mechanical stresses to which they are subject. This aspect of tendon biology is considered in some detail. Attention is briefly directed to the blood and nerve supply of tendons, for this is an important issue that relates to the intrinsic healing capacity of tendons. Structures closely related to tendons (joint capsules, tendon sheaths, pulleys, retinacula, fat pads and bursae) are also covered and the concept of a ‘supertendon’ is introduced to describe a collection of tendons in which the function of the whole complex exceeds that of its individual members. Finally, attention is drawn to the important relationship between tendons and fascia, highlighted by Wood Jones in his concept of an ‘ectoskeleton’ over half a century ago – work that is often forgotten today. PMID:18304204

  19. Tendon neuroplastic training: changing the way we think about tendon rehabilitation: a narrative review

    PubMed Central

    Rio, Ebonie; Kidgell, Dawson; Moseley, G Lorimer; Docking, Sean; Purdam, Craig; Cook, Jill

    2016-01-01

    Tendinopathy can be resistant to treatment and often recurs, implying that current treatment approaches are suboptimal. Rehabilitation programmes that have been successful in terms of pain reduction and return to sport outcomes usually include strength training. Muscle activation can induce analgesia, improving self-efficacy associated with reducing one's own pain. Furthermore, strength training is beneficial for tendon matrix structure, muscle properties and limb biomechanics. However, current tendon rehabilitation may not adequately address the corticospinal control of the muscle, which may result in altered control of muscle recruitment and the consequent tendon load, and this may contribute to recalcitrance or symptom recurrence. Outcomes of interest include the effect of strength training on tendon pain, corticospinal excitability and short interval cortical inhibition. The aims of this concept paper are to: (1) review what is known about changes to the primary motor cortex and motor control in tendinopathy, (2) identify the parameters shown to induce neuroplasticity in strength training and (3) align these principles with tendon rehabilitation loading protocols to introduce a combination approach termed as tendon neuroplastic training. Strength training is a powerful modulator of the central nervous system. In particular, corticospinal inputs are essential for motor unit recruitment and activation; however, specific strength training parameters are important for neuroplasticity. Strength training that is externally paced and akin to a skilled movement task has been shown to not only reduce tendon pain, but modulate excitatory and inhibitory control of the muscle and therefore, potentially tendon load. An improved understanding of the methods that maximise the opportunity for neuroplasticity may be an important progression in how we prescribe exercise-based rehabilitation in tendinopathy for pain modulation and potentially restoration of the corticospinal

  20. Hamstring tendon versus patellar tendon anterior cruciate ligament reconstruction using biodegradable interference fit fixation: a prospective matched-group analysis.

    PubMed

    Wagner, Michael; Kääb, Max J; Schallock, Jessica; Haas, Norbert P; Weiler, Andreas

    2005-09-01

    There are still controversies about graft selection for primary anterior cruciate ligament reconstruction, especially with respect to knee stability and functional outcome. Biodegradable interference screw fixation of hamstring tendon grafts provides clinical results similar to those achieved with identical fixation of bone-patellar tendon-bone grafts. Cohort study; Level of evidence, 2. In 1996 and 1997, primary isolated anterior cruciate ligament reconstruction using a bone-patellar tendon-bone autograft was performed in 72 patients. Since 1998, hamstring tendons were used as routine grafts. Matched patients with a hamstring tendon graft were selected from a database (n = 284). All patients were followed prospectively for a minimum of 2 years with KT-1000 arthrometer testing, International Knee Documentation Committee score, and Lysholm score. In the bone-patellar tendon-bone group, 9 patients were excluded because of bilateral rupture of the anterior cruciate ligament, 3 patients (4.2%) had a graft rupture, and 4 patients were lost to follow-up (follow-up rate, 92.1%), leaving 56 patients for a matched-group analysis. In the hamstring tendon database, the graft rupture rate was 5.6% (P = .698). The Lysholm score was 89.7 in the patellar tendon group and 94 in the hamstring tendon group (P = .003). The KT-1000 arthrometer side-to-side difference was 2.6 mm for the patellar tendon group and 2.1 mm for the hamstring tendon group (P = .041). There were significantly less positive pivot-shift test results in the hamstring tendon group (P = .005), and hamstring tendon patients showed lower thigh atrophy (P = .024) and patellofemoral crepitus (P = .003). Overall International Knee Documentation Committee scores were better (P = .001) in the hamstring tendon group (hamstring tendon: 34 x A, 21 x B, 0 x C, 0 x D; bone-patellar tendon-bone: 17 x A, 32 x B, 6 x C, 0 x D). In this comparison of anterior cruciate ligament reconstruction with bone-patellar tendon-bone and

  1. Bioreactor Design for Tendon/Ligament Engineering

    PubMed Central

    Wang, Tao; Gardiner, Bruce S.; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B.; Wang, Allan; Xu, Jiake

    2013-01-01

    Tendon and ligament injury is a worldwide health problem, but the treatment options remain limited. Tendon and ligament engineering might provide an alternative tissue source for the surgical replacement of injured tendon. A bioreactor provides a controllable environment enabling the systematic study of specific biological, biochemical, and biomechanical requirements to design and manufacture engineered tendon/ligament tissue. Furthermore, the tendon/ligament bioreactor system can provide a suitable culture environment, which mimics the dynamics of the in vivo environment for tendon/ligament maturation. For clinical settings, bioreactors also have the advantages of less-contamination risk, high reproducibility of cell propagation by minimizing manual operation, and a consistent end product. In this review, we identify the key components, design preferences, and criteria that are required for the development of an ideal bioreactor for engineering tendons and ligaments. PMID:23072472

  2. Conditioning of the Achilles tendon via ankle exercise improves correlations between sonographic measures of tendon thickness and body anthropometry.

    PubMed

    Wearing, Scott C; Grigg, Nicole L; Hooper, Sue L; Smeathers, James E

    2011-05-01

    Although conditioning is routinely used in mechanical tests of tendon in vitro, previous in vivo research evaluating the influence of body anthropometry on Achilles tendon thickness has not considered its potential effects on tendon structure. This study evaluated the relationship between Achilles tendon thickness and body anthropometry in healthy adults both before and after resistive ankle plantarflexion exercise. A convenience sample of 30 healthy male adults underwent sonographic examination of the Achilles tendon in addition to standard anthropometric measures of stature and body weight. A 10-5 MHz linear array transducer was used to acquire longitudinal sonograms of the Achilles tendon, 20 mm proximal to the tendon insertion. Participants then completed a series (90-100 repetitions) of conditioning exercises against an effective resistance between 100% and 150% body weight. Longitudinal sonograms were repeated immediately on completion of the exercise intervention, and anteroposterior Achilles tendon thickness was determined. Achilles tendon thickness was significantly reduced immediately following conditioning exercise (t = 9.71, P < 0.001), resulting in an average transverse strain of -18.8%. In contrast to preexercise measures, Achilles tendon thickness was significantly correlated with body weight (r = 0.72, P < 0.001) and to a lesser extent height (r = 0.45, P = 0.01) and body mass index (r = 0.63, P < 0.001) after exercise. Conditioning of the Achilles tendon via resistive ankle exercises induces alterations in tendon structure that substantially improve correlations between Achilles tendon thickness and body anthropometry. It is recommended that conditioning exercises, which standardize the load history of tendon, are employed before measurements of sonographic tendon thickness in vivo.

  3. Time-Dependent Alterations of MMPs, TIMPs and Tendon Structure in Human Achilles Tendons after Acute Rupture

    PubMed Central

    Minkwitz, Susann; Schmock, Aysha; Kurtoglu, Alper; Tsitsilonis, Serafeim; Manegold, Sebastian; Klatte-Schulz, Franka

    2017-01-01

    A balance between matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) is required to maintain tendon homeostasis. Variation in this balance over time might impact on the success of tendon healing. This study aimed to analyze structural changes and the expression profile of MMPs and TIMPs in human Achilles tendons at different time-points after rupture. Biopsies from 37 patients with acute Achilles tendon rupture were taken at surgery and grouped according to time after rupture: early (2–4 days), middle (5–6 days), and late (≥7 days), and intact Achilles tendons served as control. The histological score increased from the early to the late time-point after rupture, indicating the progression towards a more degenerative status. In comparison to intact tendons, qRT-PCR analysis revealed a significantly increased expression of MMP-1, -2, -13, TIMP-1, COL1A1, and COL3A1 in ruptured tendons, whereas TIMP-3 decreased. Comparing the changes over time post rupture, the expression of MMP-9, -13, and COL1A1 significantly increased, whereas MMP-3 and -10 expression decreased. TIMP expression was not significantly altered over time. MMP staining by immunohistochemistry was positive in the ruptured tendons exemplarily analyzed from early and late time-points. The study demonstrates a pivotal contribution of all investigated MMPs and TIMP-1, but a minor role of TIMP-2, -3, and -4, in the early human tendon healing process. PMID:29053586

  4. Angiogenesis in healing autogenous flexor-tendon grafts.

    PubMed

    Gelberman, R H; Chu, C R; Williams, C S; Seiler, J G; Amiel, D

    1992-09-01

    On the basis of recent evidence that flexor tendon grafts may heal without the ingrowth of vascular adhesions, eighteen autogenous donor tendons of intrasynovial and extrasynovial origin were transferred to the synovial sheaths in the forepaws of nine dogs, and controlled passive mobilization was instituted early in the postoperative period. The angiogenic responses of the tendon grafts were determined with perfusion studies with India ink followed by cleaing of the tissues with the Spalteholz technique at two, four, and six weeks. A consistent pattern of neovascularization was noted in the donor tendons of extrasynovial origin. Vascular adhesions arising from the flexor digitorum superficialis and the tendon sheath enveloped the tendon grafts by two weeks. By six weeks, the vascularity of the tendon grafts of extrasynovial origin appeared completely integrated with that of the surrounding tissues. Examination of cross sections revealed that the segments of tendon had been completely vascularized by obliquely oriented intratendinous vessels. In contrast, the flexor tendon grafts of intrasynovial origin healed without ingrowth of vascular adhesions. Primary intrinsic neovascularization took place from the proximal and, to a lesser extent, distal sites of the sutures. Examination of cross sections revealed vessels extending through the surface layer of the tendon graft, with small vessels penetrating the interior of the tendons at regular intervals.

  5. Human tendon behaviour and adaptation, in vivo

    PubMed Central

    Magnusson, S Peter; Narici, Marco V; Maganaris, Constantinos N; Kjaer, Michael

    2008-01-01

    Tendon properties contribute to the complex interaction of the central nervous system, muscle–tendon unit and bony structures to produce joint movement. Until recently limited information on human tendon behaviour in vivo was available; however, novel methodological advancements have enabled new insights to be gained in this area. The present review summarizes the progress made with respect to human tendon and aponeurosis function in vivo, and how tendons adapt to ageing, loading and unloading conditions. During low tensile loading or with passive lengthening not only the muscle is elongated, but also the tendon undergoes significant length changes, which may have implications for reflex responses. During active loading, the length change of the tendon far exceeds that of the aponeurosis, indicating that the aponeurosis may more effectively transfer force onto the tendon, which lengthens and stores elastic energy subsequently released during unloading, in a spring-like manner. In fact, data recently obtained in vivo confirm that, during walking, the human Achilles tendon provides elastic strain energy that can decrease the energy cost of locomotion. Also, new experimental evidence shows that, contrary to earlier beliefs, the metabolic activity in human tendon is remarkably high and this affords the tendon the ability to adapt to changing demands. With ageing and disuse there is a reduction in tendon stiffness, which can be mitigated with resistance exercises. Such adaptations seem advantageous for maintaining movement rapidity, reducing tendon stress and risk of injury, and possibly, for enabling muscles to operate closer to the optimum region of the length–tension relationship. PMID:17855761

  6. Deficits in heel-rise height and achilles tendon elongation occur in patients recovering from an Achilles tendon rupture.

    PubMed

    Silbernagel, Karin Grävare; Steele, Robert; Manal, Kurt

    2012-07-01

    Whether an Achilles tendon rupture is treated surgically or not, complications such as muscle weakness, decrease in heel-rise height, and gait abnormalities persist after injury. The purpose of this study was to evaluate if side-to-side differences in maximal heel-rise height can be explained by differences in Achilles tendon length. Case series; level of evidence, 4. Eight patients (mean [SD] age of 46 [13] years) with acute Achilles tendon rupture and 10 healthy subjects (mean [SD] age of 28 [8] years) were included in the study. Heel-rise height, Achilles tendon length, and patient-reported outcome were measured 3, 6, and 12 months after injury. Achilles tendon length was evaluated using motion analysis and ultrasound imaging. The Achilles tendon length test-retest reliability (intraclass correlation coefficient = 0.97) was excellent. For the healthy subjects, there were no side-to-side differences in tendon length and heel-rise height. Patients with Achilles tendon ruptures had significant differences between the injured and uninjured side for both tendon length (mean [SD] difference, 2.6-3.1 [1.2-1.4] cm, P = .017-.028) and heel-rise height (mean [SD] difference, -4.1 to -6.1 [1.7-1.8] cm, P = .012-.028). There were significant negative correlations (r = -0.943, P = .002, and r = -0.738, P = .037) between the side-to-side difference in heel-rise height and Achilles tendon length at the 6- and 12-month evaluations, respectively. The side-to-side difference found in maximal heel-rise height can be explained by a difference in Achilles tendon length in patients recovering from an Achilles tendon rupture. Minimizing tendon elongation appears to be an important treatment goal when aiming for full return of function.

  7. Measuring Regional Changes in Damaged Tendon

    NASA Astrophysics Data System (ADS)

    Frisch, Catherine Kayt Vincent

    Mechanical properties of tendon predict tendon health and function, but measuring these properties in vivo is difficult. An ultrasound-based (US) analysis technique called acoustoelastography (AE) uses load-dependent changes in the reflected US signal to estimate tissue stiffness non-invasively. This thesis explores whether AE can provide information about stiffness alteration resulting from tendon tears both ex vivo and in vivo. An ex vivo ovine infraspinatus tendon model suggests that the relative load transmitted by the different tendon layers transmit different fractions of the load and that ultrasound echo intensity change during cyclic loading decreases, becoming less consistent once the tendon is torn. An in vivo human tibialis anterior tendon model using electrically stimulated twitch contractions investigated the feasibility of measuring the effect in vivo. Four of the five subjects showed the expected change and that the muscle contraction times calculated using the average grayscale echo intensity change compared favorably with the times calculated based on the force data. Finally an AE pilot study with patients who had rotator cuff tendon tears found that controlling the applied load and the US view of the system will be crucial to a successful in vivo study.

  8. Tendon sheath fibroma in the thigh.

    PubMed

    Moretti, Vincent M; Ashana, Adedayo O; de la Cruz, Michael; Lackman, Richard D

    2012-04-01

    Tendon sheath fibromas are rare, benign soft tissue tumors that are predominantly found in the fingers, hands, and wrists of young adult men. This article describes a tendon sheath fibroma that developed in the thigh of a 70-year-old man, the only known tendon sheath fibroma to form in this location. Similar to tendon sheath fibromas that develop elsewhere, our patient's lesion presented as a painless, slow-growing soft tissue nodule. Physical examination revealed a firm, nontender mass with no other associated signs or symptoms. Although the imaging appearance of tendon sheath fibromas varies, our patient's lesion appeared dark on T1- and bright on T2-weighted magnetic resonance imaging. It was well marginated and enhanced with contrast.Histologically, tendon sheath fibromas are composed of dense fibrocollagenous stromas with scattered spindle-shaped fibroblasts and narrow slit-like vascular spaces. Most tendon sheath fibromas can be successfully removed by marginal excision, although 24% of lesions recur. No lesions have metastasized. Our patient's tendon sheath fibroma was removed by marginal excision, and the patient remained disease free 35 months postoperatively. Despite its rarity, tendon sheath fibroma should be included in the differential diagnosis of a thigh mass on physical examination or imaging, especially if it is painless, nontender, benign appearing, and present in men. Copyright 2012, SLACK Incorporated.

  9. Comparison of foot muscle morphology and foot kinematics between recreational runners with normal feet and with asymptomatic over-pronated feet.

    PubMed

    Zhang, Xianyi; Aeles, Jeroen; Vanwanseele, Benedicte

    2017-05-01

    Over-pronated feet are common in adults and are associated with lower limb injuries. Studying the foot muscle morphology and foot kinematic patterns is important for understanding the mechanism of over-pronation related injuries. The aim of this study is to compare the foot muscle morphology and foot inter-segmental kinematics between recreational runners with normal feet and those with asymptomatic over-pronated feet. A total of 26 recreational runners (17 had normal feet and 9 had over-pronated feet) participated in this study and their foot type was assessed using the 6-item Foot Posture Index. Selected foot muscles were scanned using an ultrasound device and the scanned images were processed to measure the thickness and cross-sectional area of the muscles. Muscles of interest include abductor hallucis, abductor digiti minimi, flexor digitorum brevis and longus, tibialis anterior and peroneus muscles. Foot kinematic data during walking was collected using a 3D motion capture system incorporating the Oxford Foot Model. The results show that individuals with over-pronated feet have larger size of abductor hallucis, flexor digitorum brevis and longus and smaller abductor digiti minimi than controls. Higher rearfoot peak eversion and forefoot peak supination during walking were observed in individuals with over-pronated feet. However, during gait the forefoot peak abduction was comparable. These findings indicate that in active asymptomatic individuals with over-pronated feet, the foot muscle morphology is adapted to increase control of the foot motion. The morphological characteristics of the foot muscles in asymptomatic individuals with over-pronated feet may affect their foot kinematics and benefit prevention from injuries. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. The promoting effect of pentadecapeptide BPC 157 on tendon healing involves tendon outgrowth, cell survival, and cell migration.

    PubMed

    Chang, Chung-Hsun; Tsai, Wen-Chung; Lin, Miao-Sui; Hsu, Ya-Hui; Pang, Jong-Hwei Su

    2011-03-01

    Pentadecapeptide BPC 157, composed of 15 amino acids, is a partial sequence of body protection compound (BPC) that is discovered in and isolated from human gastric juice. Experimentally it has been demonstrated to accelerate the healing of many different wounds, including transected rat Achilles tendon. This study was designed to investigate the potential mechanism of BPC 157 to enhance healing of injured tendon. The outgrowth of tendon fibroblasts from tendon explants cultured with or without BPC 157 was examined. Results showed that BPC 157 significantly accelerated the outgrowth of tendon explants. Cell proliferation of cultured tendon fibroblasts derived from rat Achilles tendon was not directly affected by BPC 157 as evaluated by MTT assay. However, the survival of BPC 157-treated cells was significantly increased under the H(2)O(2) stress. BPC 157 markedly increased the in vitro migration of tendon fibroblasts in a dose-dependent manner as revealed by transwell filter migration assay. BPC 157 also dose dependently accelerated the spreading of tendon fibroblasts on culture dishes. The F-actin formation as detected by FITC-phalloidin staining was induced in BPC 157-treated fibroblasts. The protein expression and activation of FAK and paxillin were determined by Western blot analysis, and the phosphorylation levels of both FAK and paxillin were dose dependently increased by BPC 157 while the total amounts of protein was unaltered. In conclusion, BPC 157 promotes the ex vivo outgrowth of tendon fibroblasts from tendon explants, cell survival under stress, and the in vitro migration of tendon fibroblasts, which is likely mediated by the activation of the FAK-paxillin pathway.

  11. Role of tissue-engineered artificial tendon in healing of a large Achilles tendon defect model in rabbits.

    PubMed

    Moshiri, Ali; Oryan, Ahmad; Meimandi-Parizi, Abdolhamid

    2013-09-01

    Treatment of large Achilles tendon defects is technically demanding. Tissue engineering is an option. We constructed a collagen-based artificial tendon, covered it with a polydioxanon (PDS) sheath, and studied the role of this bioimplant on experimental tendon healing in vivo. A 2-cm tendon gap was created in the left Achilles tendon of rabbits (n = 120). The animals were randomly divided into 3 groups: control (no implant), treated with tridimensional-collagen, and treated with tridimensional-collagen-bidimensional-PDS implants. Each group was divided into 2 subgroups of 60 and 120 days postinjury (DPI). Another 50 pilot animals were used to study the host-implant interaction. Physical activity of the animals was scored and ultrasonographic and bioelectrical characteristics of the injured tendons were investigated weekly. After euthanasia, macro, micro, and nano morphologies and biophysical and biomechanical characteristics of the healing tendons were studied. Treatment improved function of the animals, time dependently. At 60 and 120 DPI, the treated tendons showed significantly higher maximum load, yield, stiffness, stress, and modulus of elasticity compared with controls. The collagen implant induced inflammation and absorbed the migrating fibroblasts in the defect area. By its unique architecture, it aligned the fibroblasts and guided their proliferation and collagen deposition along the stress line of the tendon and resulted in improved collagen density, micro-amp, micro-ohm, water uptake, and delivery of the regenerated tissue. The PDS-sheath covering amplified these characteristics. The implants were gradually absorbed and replaced by a new tendon. Minimum amounts of peritendinous adhesion, muscle atrophy, and fibrosis were observed in the treated groups. Some remnants of the implants were preserved and accepted as a part of the new tendon. The implants were cytocompatible, biocompatible, biodegradable, and effective in tendon healing and regeneration. This

  12. Muscle stiffness of posterior lower leg in runners with a history of medial tibial stress syndrome.

    PubMed

    Saeki, J; Nakamura, M; Nakao, S; Fujita, K; Yanase, K; Ichihashi, N

    2018-01-01

    Previous history of medial tibial stress syndrome (MTSS) is a risk factor for MTSS relapse, which suggests that there might be some physical factors that are related to MTSS development in runners with a history of MTSS. The relationship between MTSS and muscle stiffness can be assessed in a cross-sectional study that measures muscle stiffness in subjects with a history of MTSS, who do not have pain at the time of measurement, and in those without a history of MTSS. The purpose of this study was to compare the shear elastic modulus, which is an index of muscle stiffness, of all posterior lower leg muscles of subjects with a history of MTSS and those with no history and investigate which muscles could be related to MTSS. Twenty-four male collegiate runners (age, 20.0±1.7 years; height, 172.7±4.8 cm; weight, 57.3±3.7 kg) participated in this study; 14 had a history of MTSS, and 10 did not. The shear elastic moduli of the lateral gastrocnemius, medial gastrocnemius, soleus, peroneus longus, peroneus brevis, flexor hallucis longus, flexor digitorum longus, and tibialis posterior were measured using shear wave elastography. The shear elastic moduli of the flexor digitorum longus and tibialis posterior were significantly higher in subjects with a history of MTSS than in those with no history. However, there was no significant difference in the shear elastic moduli of other muscles. The results of this study suggest that flexor digitorum longus and tibialis posterior stiffness could be related to MTSS. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Calcific retropharyngeal tendinitis. [Radiological findings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karasick, D.; Karasick, S.

    1981-12-01

    Calcific retropharyngeal tendinitis is an imflammation of the longus colli muscle tendon which is located on the anterior surface of the verterbral column extending from the atlas to the third thoracic vertebra. The acute inflammatory condition is selflimiting with symptoms consisting of a gradually increasing neck pain often associated with throat pain and difficulty swallowing. The pain is aggravated by head and neck movement. Clinically the condition can be confused with retropharyngeal absecess, meningitis, infectious spondylitis, and post-traumatic muscle spasm. The radiographic features of this condition consist of pre-vertebral soft tissue swelling from C1 to C4 and amorphous calcific densitymore » in the longus colli tendon anterior to the body of C2 and inferior to the anterior arch of C1.« less

  14. Surgical repair of chronic patellar tendon rupture in total knee replacement with ipsilateral hamstring tendons.

    PubMed

    Spoliti, Marco; Giai Via, Alessio; Padulo, Johnny; Oliva, Francesco; Del Buono, Angelo; Maffulli, Nicola

    2016-10-01

    Patellar tendon rupture is a serious complication of total knee arthroplasty (TKA). Its reconstruction in patients with chronic ruptures is technically demanding. This article reports the results of surgical reconstruction of neglected patellar tendon rupture in TKA using autologous hamstring tendons. Nine TKA patients (six women and three men) (mean age at index surgery 68 years) with chronic patellar tendon tears underwent reconstruction with ipsilateral hamstrings tendon, leaving the distal insertion in situ. The clinical diagnosis was supported by imaging (anterior-posterior and 30° flexion lateral radiographs). Insall-Salvati index, range of motion, and leg extension test were recorded preoperatively and at last follow-up. The modified Cincinnati rating system and the Kujala score were administered. The patients sustained the patellar tendon tear an average of 8 weeks before the procedure. At final follow-up of 4 years (range 2-8 years), the median of extension lag was 5° (range 0°-15°; DS = 5). The median of post-operative Insall-Salvati index was 1.4 (range 1.3-1.8; SD = 0.15; p = 0.002) compared to the preoperative index of 1.7 (range 1.5-2.2; SD = 0.23). The mean modified Cincinnati and Kujala scores significantly increased compared with the preoperative ones (p < 0.01). At final follow-up, all patients were able to walk without brace or aids, and they were satisfied with the procedure. Based on our retrospective study of nine patients, reconstruction of neglected patellar tendon rupture in TKA with autologous hamstring tendons is feasible and safe, and provides good functional recovery. Case series, Level IV.

  15. Structure-mechanics relationships in mineralized tendons.

    PubMed

    Spiesz, Ewa M; Zysset, Philippe K

    2015-12-01

    In this paper, we review the hierarchical structure and the resulting elastic properties of mineralized tendons as obtained by various multiscale experimental and computational methods spanning from nano- to macroscale. The mechanical properties of mineralized collagen fibres are important to understand the mechanics of hard tissues constituted by complex arrangements of these fibres, like in human lamellar bone. The uniaxial mineralized collagen fibre array naturally occurring in avian tendons is a well studied model tissue for investigating various stages of tissue mineralization and the corresponding elastic properties. Some avian tendons mineralize with maturation, which results in a graded structure containing two zones of distinct morphology, circumferential and interstitial. These zones exhibit different amounts of mineral, collagen, pores and a different mineral distribution between collagen fibrillar and extrafibrillar space that lead to distinct elastic properties. Mineralized tendon cells have two phenotypes: elongated tenocytes placed between fibres in the circumferential zone and cuboidal cells with lower aspect ratios in the interstitial zone. Interestingly some regions of avian tendons seem to be predestined to mineralization, which is exhibited as specific collagen cross-linking patterns as well as distribution of minor tendon constituents (like proteoglycans) and loss of collagen crimp. Results of investigations in naturally mineralizing avian tendons may be useful in understanding the pathological mineralization occurring in some human tendons. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Ultrasonographic assessment of the equine palmar tendons

    PubMed Central

    Padaliya, N. R.; Ranpariya, J. J.; Kumar, Dharmendra; Javia, C. B.; Barvalia, D. R.

    2015-01-01

    Aim: The present study was conducted to evaluate the equine palmar tendon by ultrasonography (USG) in standing the position. Materials and Methods: USG of palmar tendons was performed in 40 adult horses using linear transducer having frequency of 10-18 MHz (e-soate, My Lab FIVE) and L52 linear array transducer (Titan, SonoSite) with frequencies ranging from 8 to 10 MHz. Palmar tendon was divided into 7 levels from distal to accessory carpal bone up to ergot in transverse scanning and 3 levels in longitudinal scanning. Results: The USG evaluation was very useful for diagnosis of affections of the conditions such as chronic bowed tendon, suspensory ligament desmitis, carpal sheath tenosynovitis and digital sheath effusions. The mean cross-sectional area (cm2) of affected tendons was significantly increased in affected than normal tendons. The echogenicity was also found reduced in affected tendons and ligaments along with disorganization of fiber alignment depending on the severity of lesion and injury. Conclusion: USG proved ideal diagnostic tool for diagnosis and post-treatment healing assessment of tendon injuries in horses. PMID:27047074

  17. Surgical Treatment for Failure of Repair of Patellar and Quadriceps Tendon Rupture With Ipsilateral Hamstring Tendon Graft.

    PubMed

    Maffulli, Nicola; Papalia, Rocco; Torre, Guglielmo; Denaro, Vincenzo

    2017-03-01

    Tears of the patellar and quadriceps tendon are common in the active population, especially in athletes. At present, several techniques for surgical repair and reconstruction are available. When reruptures occur, a reconstruction is mandatory. In the present paper, we describe a surgical technique for patellar and quadriceps tendon reconstruction using ipsilateral hamstring autograft. After routine hamstring tendon harvesting, the tendon ends are prepared using a whip stitch. A transverse tunnel is drilled in the midportion of the patella, the hamstring graft is passed through the patella, and firmly secured to the patellar tunnel openings with sutures. The details of the technique are fully described. Autologous ipsilateral hamstring tendon grafts provide a secure sound means to manage these challenging injuries.

  18. Markers for the identification of tendon-derived stem cells in vitro and tendon stem cells in situ - update and future development.

    PubMed

    Lui, Pauline Po Yee

    2015-06-02

    The efficacy of tendon-derived stem cells (TDSCs) for the promotion of tendon and tendon-bone junction repair has been reported in animal studies. Modulation of the tendon stem cell niche in vivo has also been reported to influence tendon structure. There is a need to have specific and reliable markers that can define TDSCs in vitro and tendon stem cells in situ for several reasons: to understand the basic biology of TDSCs and their subpopulations in vitro; to understand the identity, niches and functions of tendon/progenitor stem cells in vivo; to meet the governmental regulatory requirements for quality of TDSCs when translating the exciting preclinical findings into clinical trial/practice; and to develop new treatment strategies for mobilizing endogenous stem/progenitor cells in tendon. TDSCs were reported to express the common mesenchymal stem cell (MSC) markers and some embryonic stem cell (ESC) markers, and there were attempts to use these markers to label tendon stem cells in situ. Are these stem cell markers useful for the identification of TDSCs in vitro and tracking of tendon stem cells in situ? This review aims to discuss the values of the panel of MSC, ESC and tendon-related markers for the identification of TDSCs in vitro. Important factors influencing marker expression by TDSCs are discussed. The usefulness and limitations of the panel of MSC, ESC and tendon-related markers for tracking stem cells in tendon, especially tendon stem cells, in situ are then reviewed. Future research directions are proposed.

  19. Collagen structure of tendon relates to function.

    PubMed

    Franchi, Marco; Trirè, Alessandra; Quaranta, Marilisa; Orsini, Ester; Ottani, Victoria

    2007-03-30

    A tendon is a tough band of fibrous connective tissue that connects muscle to bone, designed to transmit forces and withstand tension during muscle contraction. Tendon may be surrounded by different structures: 1) fibrous sheaths or retinaculae; 2) reflection pulleys; 3) synovial sheaths; 4) peritendon sheaths; 5) tendon bursae. Tendons contain a) few cells, mostly represented by tenoblasts along with endothelial cells and some chondrocytes; b) proteoglycans (PGs), mainly decorin and hyaluronan, and c) collagen, mostly type I. Tendon is a good example of a high ordered extracellular matrix in which collagen molecules assemble into filamentous collagen fibrils (formed by microfibrils) which aggregate to form collagen fibers, the main structural components. It represents a multihierarchical structure as it contains collagen molecules arranged in fibrils then grouped in fibril bundles, fascicles and fiber bundles that are almost parallel to the long axis of the tendon, named as primary, secondary and tertiary bundles. Collagen fibrils in tendons show prevalently large diameter, a D-period of about 67 nm and appear built of collagen molecules lying at a slight angle (< 5 degrees). Under polarized light microscopy the collagen fiber bundles appear crimped with alternative dark and light transverse bands. In recent studies tendon crimps observed via SEM and TEM show that the single collagen fibrils suddenly changing their direction contain knots. These knots of collagen fibrils inside each tendon crimp have been termed "fibrillar crimps", and even if they show different aspects they all may fulfil the same functional role. As integral component of musculoskeletal system, the tendon acts to transmit muscle forces to the skeletal system. There is no complete understanding of the mechanisms in transmitting/absorbing tensional forces within the tendon; however it seems likely that a flattening of tendon crimps may occur at a first stage of tendon stretching. Increasing

  20. IFSSH Flexor Tendon Committee report 2014: from the IFSSH Flexor Tendon Committee (Chairman: Jin Bo Tang).

    PubMed

    Tang, Jin Bo; Chang, James; Elliot, David; Lalonde, Donald H; Sandow, Michael; Vögelin, Esther

    2014-01-01

    Hand surgeons continue to search for the best surgical flexor tendon repair and treatment of the tendon sheaths and pulleys, and they are attempting to establish postoperative regimens that fit diverse clinical needs. It is the purpose of this report to present the current views, methods, and suggestions of six senior hand surgeons from six different countries - all experienced in tendon repair and reconstruction. Although certainly there is common ground, the report presents provocative views and approaches. The report reflects an update in the views of the committee. We hope that it is helpful to surgeons and therapists in treating flexor tendon injuries.

  1. Grasp Assist Device with Shared Tendon Actuator Assembly

    NASA Technical Reports Server (NTRS)

    Ihrke, Chris A. (Inventor); Bergelin, Bryan J. (Inventor); Bridgwater, Lyndon (Inventor)

    2015-01-01

    A grasp assist device includes a glove with first and second tendon-driven fingers, a tendon, and a sleeve with a shared tendon actuator assembly. Tendon ends are connected to the respective first and second fingers. The actuator assembly includes a drive assembly having a drive axis and a tendon hook. The tendon hook, which defines an arcuate surface slot, is linearly translatable along the drive axis via the drive assembly, e.g., a servo motor thereof. The flexible tendon is routed through the surface slot such that the surface slot divides the flexible tendon into two portions each terminating in a respective one of the first and second ends. The drive assembly may include a ball screw and nut. An end cap of the actuator assembly may define two channels through which the respective tendon portions pass. The servo motor may be positioned off-axis with respect to the drive axis.

  2. Evolution of the Achilles tendon: The athlete's Achilles heel?

    PubMed

    Malvankar, S; Khan, W S

    2011-12-01

    The Achilles tendon is believed to have first developed two million years ago enabling humans to run twice as fast. However if the Achilles tendon is so important in terms of evolution, then why is this tendon so prone to injury - especially for those more active like athletes. The Achilles tendon had an integral role in evolving apes from a herbivorous diet to early humans who started hunting for food over longer distances, resulting in bipedal locomotion. Evolutionary advantages of the Achilles tendon includes it being the strongest tendon in the body, having an energy-saving mechanism for fast locomotion, allows humans to jump and run, and additionally is a spring and shock absorber during gait. Considering these benefits it is therefore not surprising that studies have shown athletes have thicker Achilles tendons than subjects who are less active. However, contradictory to these findings that show the importance of the Achilles tendon for athletes, it is well known that obtaining an Achilles tendon injury for an athlete can be career-altering. A disadvantage of the Achilles tendon is that the aetiology of its pathology is complicated. Achilles tendon ruptures are believed to be caused by overloading the tensed tendon, like during sports. However studies have also shown athlete Achilles tendon ruptures to have degenerative changes in the tendon. Other flaws of the Achilles tendon are its non-uniform vascularity and incomplete repair system which may suggest the Achilles tendon is on the edge of evolution. Research has shown that there is a genetic influence on the predisposition a person has towards Achilles tendon injuries. So if this tendon is here to stay in our anatomy, and it probably is due to the slow rate of evolution in humans, research in genetic modification could be used to decrease athletes' predisposition to Achilles tendinopathy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Peroneal tendon displacement accompanying intra-articular calcaneal fractures.

    PubMed

    Toussaint, Rull James; Lin, Darius; Ehrlichman, Lauren K; Ellington, J Kent; Strasser, Nicholas; Kwon, John Y

    2014-02-19

    Peroneal tendon displacement (subluxation or dislocation) accompanying an intra-articular calcaneal fracture is often undetected and under-treated. The goals of this study were to determine (1) the prevalence of peroneal tendon displacement accompanying intra-articular calcaneal fractures, (2) the association of tendon displacement with fracture classifications, (3) the association of tendon displacement with heel width, and (4) the rate of missed diagnosis of the tendon displacement on radiographs and computed tomography (CT) scans and the resulting treatment rate. A retrospective radiographic review of all calcaneal fractures presenting at three institutions from June 30, 2006, to June 30, 2011, was performed. CT imaging of 421 intra-articular calcaneal fractures involving the posterior facet was available for review. The prevalence of peroneal tendon displacement was noted and its associations with fracture classification and heel width were evaluated. Peroneal tendon displacement was identified in 118 (28.0%) of the 421 calcaneal fracture cases. The presence of tendon displacement was significantly associated with joint-depression fractures compared with tongue-type fractures (p < 0.001). Only twelve (10.2%) of the 118 cases of peroneal tendon displacement had been identified in the radiology reports. Although sixty-five (55.1%) of the fractures with tendon displacement had been treated with internal fixation, the tendon displacement was treated surgically in only seven (10.8%) of these cases. Analysis of CT images showed a 28% prevalence of peroneal tendon displacement accompanying intra-articular calcaneal fractures. Surgeons and radiologists are encouraged to consider this association.

  4. Subscapularis tendon tears

    PubMed Central

    Lenart, Brett A.; Ticker, Jonathan B.

    2017-01-01

    Tears of the subscapularis tendon have been under-recognised until recently. Therefore, a high index of suspicion is essential for diagnosis. A directed physical examination, including the lift-off, belly-press and increased passive external rotation can help identify tears of the subscapularis. All planes on MR imaging should be carefully evaluated to identify tears of the subscapularis, retraction, atrophy and biceps pathology. Due to the tendency of the tendon to retract medially, acute and traumatic full-thickness tears should be repaired. Chronic tears without significant degeneration should be considered for repair if no contraindication exists. Arthroscopic repair can be performed using a 30-degree arthroscope and a laterally-based single row repair; one anchor for full thickness tears ⩽ 50% of tendon length and two anchors for those ⩾ 50% of tendon length. Biceps pathology, which is invariably present, should be addressed by tenotomy or tenodesis. Timing of post-operative rehabilitation is dictated by the size of the repair and the security of the repair construct. The stages of rehabilitation typically involve a period of immobilisation followed by range of movement exercises, with a delay in active internal rotation (IR) and strengthening in IR. Cite this article: EFORT Open Rev 2017;2:484–495. DOI: 10.1302/2058-5241.2.170015 PMID:29387471

  5. Specialization of tendon mechanical properties results from interfascicular differences

    PubMed Central

    Thorpe, Chavaunne T.; Udeze, Chineye P.; Birch, Helen L.; Clegg, Peter D.; Screen, Hazel R. C.

    2012-01-01

    Tendons transfer force from muscle to bone. Specific tendons, including the equine superficial digital flexor tendon (SDFT), also store and return energy. For efficient function, energy-storing tendons need to be more extensible than positional tendons such as the common digital extensor tendon (CDET), and when tested in vitro have a lower modulus and failure stress, but a higher failure strain. It is not known how differences in matrix organization contribute to distinct mechanical properties in functionally different tendons. We investigated the properties of whole tendons, tendon fascicles and the fascicular interface in the high-strain energy-storing SDFT and low-strain positional CDET. Fascicles failed at lower stresses and strains than tendons. The SDFT was more extensible than the CDET, but SDFT fascicles failed at lower strains than CDET fascicles, resulting in large differences between tendon and fascicle failure strain in the SDFT. At physiological loads, the stiffness at the fascicular interface was lower in the SDFT samples, enabling a greater fascicle sliding that could account for differences in tendon and fascicle failure strain. Sliding between fascicles prior to fascicle extension in the SDFT may allow the large extensions required in energy-storing tendons while protecting fascicles from damage. PMID:22764132

  6. Specialization of tendon mechanical properties results from interfascicular differences.

    PubMed

    Thorpe, Chavaunne T; Udeze, Chineye P; Birch, Helen L; Clegg, Peter D; Screen, Hazel R C

    2012-11-07

    Tendons transfer force from muscle to bone. Specific tendons, including the equine superficial digital flexor tendon (SDFT), also store and return energy. For efficient function, energy-storing tendons need to be more extensible than positional tendons such as the common digital extensor tendon (CDET), and when tested in vitro have a lower modulus and failure stress, but a higher failure strain. It is not known how differences in matrix organization contribute to distinct mechanical properties in functionally different tendons. We investigated the properties of whole tendons, tendon fascicles and the fascicular interface in the high-strain energy-storing SDFT and low-strain positional CDET. Fascicles failed at lower stresses and strains than tendons. The SDFT was more extensible than the CDET, but SDFT fascicles failed at lower strains than CDET fascicles, resulting in large differences between tendon and fascicle failure strain in the SDFT. At physiological loads, the stiffness at the fascicular interface was lower in the SDFT samples, enabling a greater fascicle sliding that could account for differences in tendon and fascicle failure strain. Sliding between fascicles prior to fascicle extension in the SDFT may allow the large extensions required in energy-storing tendons while protecting fascicles from damage.

  7. The interfascicular matrix enables fascicle sliding and recovery in tendon, and behaves more elastically in energy storing tendons

    PubMed Central

    Thorpe, Chavaunne T.; Godinho, Marta S.C.; Riley, Graham P.; Birch, Helen L.; Clegg, Peter D.; Screen, Hazel R.C.

    2015-01-01

    While the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the cost of locomotion. Energy storing tendons experience extremely high strains and need to be able to recoil efficiently for maximum energy storage and return. In the equine forelimb, the energy storing superficial digital flexor tendon (SDFT) has much higher failure strains than the positional common digital extensor tendon (CDET). However, we have previously shown that this is not due to differences in the properties of the SDFT and CDET fascicles (the largest tendon subunits). Instead, there is a greater capacity for interfascicular sliding in the SDFT which facilitates the greater extensions in this particular tendon (Thorpe et al., 2012). In the current study, we exposed fascicles and interfascicular matrix (IFM) from the SDFT and CDET to cyclic loading followed by a test to failure. The results show that IFM mechanical behaviour is not a result of irreversible deformation, but the IFM is able to withstand cyclic loading, and is more elastic in the SDFT than in the CDET. We also assessed the effect of ageing on IFM properties, demonstrating that the IFM is less able to resist repetitive loading as it ages, becoming stiffer with increasing age in the SDFT. These results provide further indications that the IFM is important for efficient function in energy storing tendons, and age-related alterations to the IFM may compromise function and predispose older tendons to injury. PMID:25958330

  8. The interfascicular matrix enables fascicle sliding and recovery in tendon, and behaves more elastically in energy storing tendons.

    PubMed

    Thorpe, Chavaunne T; Godinho, Marta S C; Riley, Graham P; Birch, Helen L; Clegg, Peter D; Screen, Hazel R C

    2015-12-01

    While the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the cost of locomotion. Energy storing tendons experience extremely high strains and need to be able to recoil efficiently for maximum energy storage and return. In the equine forelimb, the energy storing superficial digital flexor tendon (SDFT) has much higher failure strains than the positional common digital extensor tendon (CDET). However, we have previously shown that this is not due to differences in the properties of the SDFT and CDET fascicles (the largest tendon subunits). Instead, there is a greater capacity for interfascicular sliding in the SDFT which facilitates the greater extensions in this particular tendon (Thorpe et al., 2012). In the current study, we exposed fascicles and interfascicular matrix (IFM) from the SDFT and CDET to cyclic loading followed by a test to failure. The results show that IFM mechanical behaviour is not a result of irreversible deformation, but the IFM is able to withstand cyclic loading, and is more elastic in the SDFT than in the CDET. We also assessed the effect of ageing on IFM properties, demonstrating that the IFM is less able to resist repetitive loading as it ages, becoming stiffer with increasing age in the SDFT. These results provide further indications that the IFM is important for efficient function in energy storing tendons, and age-related alterations to the IFM may compromise function and predispose older tendons to injury. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Partial supraspinatus tears are associated with tendon lengthening.

    PubMed

    Farshad-Amacker, Nadja A; Buck, Florian M; Farshad, Mazda; Pfirrmann, Christian W A; Gerber, Christian

    2015-02-01

    Tendon tear may result in muscular retraction with the loss of contractile amplitude and strength of the rotator cuff muscles. Currently, neither a validated method of measuring supraspinatus tendon length nor normal values are known. It was therefore the purpose of this study to measure the normal length of the supraspinatus tendon and to determine whether partial tears are associated with changes in tendon length. MR examinations of 49 asymptomatic volunteers and 37 patients with arthroscopically proven, isolated partial tears of the supraspinatus tendon were compared. The ratio of the extramuscular tendon length to the distance between the footprint and the glenoid surface was calculated (TL/FG ratio). Tendon length measurements were taken by two independent readers at the bursal and articular surfaces at the anterior, the central and the posterior parts of the tendon. TL/FG ratios at the bursal surface of tendons with partial tears were significantly higher than those in the control group [anterior: 0.78 ± 0.20 vs. 0.66 ± 0.15 (p < 0.05); central: 0.61 ± 0.13 vs. 0.52 ± 0.10 (p < 0.05); posterior: 0.57 ± 0.15 vs. 0.52 ± 0.10 (p < 0.05)]. At the articular surface, differences were significant only anteriorly [0.60 ± 0.13, vs. 0.54 ± 0.10 (p < 0.05)]. A cut-off TL/FG ratio of 0.63 for measurements at the bursal surface in the center of the tendon achieved a sensitivity of 46 % and a specificity of 92 % for the identification of partial cuff tearing. A reproducible method for measurement of extramuscular supraspinatus tendon length is described. Partial tearing of the supraspinatus tendon is associated with significant tendon lengthening, suggesting failure in continuity, and this is most reliably measured on the bursal surface. III.

  10. Rat supraspinatus muscle atrophy after tendon detachment.

    PubMed

    Barton, Elisabeth R; Gimbel, Jonathan A; Williams, Gerald R; Soslowsky, Louis J

    2005-03-01

    Rotator cuff tears are one of the most common tendon disorders found in the healthy population. Tendon tears not only affect the biomechanical properties of the tendon, but can also lead to debilitation of the muscles attached to the damaged tendons. The changes that occur in the muscle after tendon detachment are not well understood. A rat rotator cuff model was utilized to determine the time course of changes that occur in the supraspinatus muscle after tendon detachment. It was hypothesized that the lack of load on the supraspinatus muscle would cause a significant decrease in muscle mass and a conversion of muscle fiber properties toward those of fast fiber types. Tendons were detached at the insertion on the humerus without repair. Muscle mass, morphology and fiber properties were measured at one, two, four, eight, and 16 weeks after detachment. Tendon detachment resulted in a rapid loss of muscle mass, an increase in the proportion of fast muscle fibers, and an increase in the fibrotic content of the muscle bed, concomitant with the appearance of adhesions of the tendon to surrounding surfaces. At 16 weeks post-detachment, muscle mass and the fiber properties in the deep muscle layers returned to normal levels. However, the fiber shifts observed in the superficial layers persisted throughout the experiment. These results suggest that load returned to the muscle via adhesions to surrounding surfaces, which may be sufficient to reverse changes in muscle mass.

  11. The flexor digitorum profundus "demi-tendon"--a new technique for passage of the flexor profundus tendon through the A4 pulley.

    PubMed

    Elliot, D; Khandwala, A R; Ragoowansi, R

    2001-10-01

    The flexor digitorum profundus (FDP) tendon may retract after avulsion or division in Zone 1. When treatment has been delayed, the oedematous tendon can be too swollen to pass freely through the A4 pulley. We present a new technique for dealing with this situation which depends on the "double-barrelled" nature of the distal part of the FDP tendon. One half of the tendon is excised longitudinally and the remaining "demi-tendon" is passed through the intact A4 pulley to allow tendon repair or re-attachment. This technique has been used in six cases in which passage of the FDP tendon through the A4 pulley would otherwise have been impossible. Copyright 2001 The British Society for Surgery of the Hand.

  12. THE ROLE OF MECHANOBIOLOGY IN TENDON HEALING

    PubMed Central

    Killian, Megan L.; Cavinatto, Leonardo; Galatz, Leesa M.; Thomopoulos, Stavros

    2011-01-01

    Mechanical cues affect tendon healing, homeostasis, and development in a variety of settings. Alterations in the mechanical environment are known to result in changes in the expression of extracellular matrix proteins, growth factors, transcription factors, and cytokines that can alter tendon structure and cell viability. Loss of muscle force in utero or in the immediate postnatal period delays tendon and enthesis development. The response of healing tendons to mechanical load varies depending on anatomic location. Flexor tendons require motion to prevent adhesion formation, yet excessive force results in gap formation and subsequent weakening of the repair. Excessive motion in the setting of anterior cruciate ligament reconstruction causes accumulation of macrophages, which are detrimental to tendon graft healing. Complete removal of load is detrimental to rotator cuff healing, yet large forces are also harmful. Controlled loading can enhance healing in most settings; however, a fine balance must be reached between loads that are too low (leading to a catabolic state) and too high (leading to micro-damage). This review will summarize existing knowledge of the mechanobiology of tendon development, homeostasis, and healing. PMID:22244066

  13. A novel biodegradable PCL film for tendon reconstruction: Achilles tendon defect model in rats.

    PubMed

    Kazimoğlu, C; Bölükbaşi, S; Kanatli, U; Senköylü, A; Altun, N S; Babaç, C; Yavuz, H; Pişkin, E

    2003-09-01

    This study aims to investigate applicability of poly(epsilon-caprolactone) (PCL) biodegradable films for repair of gaps in Achilles tendons in a rat model, also comparing surgical repair versus no repair approaches. PCL was synthesized with tailor-made properties, then, PCL films were prepared by solvent casting. Seventy-five outbred Sprague-Dawley rats were randomly allocated into five groups: (i) sham operated (skin incision only); (ii) no repair (complete division of the Achilles tendon and plantaris tendon without repair); (iii) Achilles repair (with a modified Kessler type suture); and (iv) plasty of Achilles tendon defects with the biodegradable PCL films, and (v) animals subjected to 1 cm mid-substance defect with no repair. Functional performance was determined from the measurements of hindpaw prints utilizing the Achilles functional index. The animals were killed 8 weeks after surgery and histological and biomechanical evaluations were made. All groups subjected to Achilles tendon division had a significant functional impairment that gradually improved so that by day 28 there were no functional impairments in any group whereas animals with a defect remained impaired. The magnitude of the biomechanical and morphological changes at postoperative 8 weeks were similar for no repair group (conservative), Achilles repair group and tendonplasty group (biodegradable PCL film group). The initial rate of functional recovery was significantly different for primary suture, Achilles repair group and PCL film group (p>0.01). But, at the 28th day, functional recovery was quite similar to the other groups. In summary, our results suggest that the PCL film can be an alternative biomaterial for tendon replacement.

  14. Pathomorphism of spiral tibial fractures in computed tomography imaging.

    PubMed

    Guzik, Grzegorz

    2011-01-01

    Spiral fractures of the tibia are virtually homogeneous with regard to their pathomorphism. The differences that are seen concern the level of fracture of the fibula, and, to a lesser extent, the level of fracture of the tibia, the length of fracture cleft, and limb shortening following the trauma. While conventional radiographs provide sufficient information about the pathomorphism of fractures, computed tomography can be useful in demonstrating the spatial arrangement of bone fragments and topography of soft tissues surrounding the fracture site. Multiple cross-sectional computed tomography views of spiral fractures of the tibia show the details of the alignment of bone chips at the fracture site, axis of the tibial fracture cleft, and topography of soft tissues that are not visible on standard radiographs. A model of a spiral tibial fracture reveals periosteal stretching with increasing spiral and longitudinal displacement. The cleft in tibial fractures has a spiral shape and its line is invariable. Every spiral fracture of both crural bones results in extensive damage to the periosteum and may damage bellies of the long flexor muscle of toes, flexor hallucis longus as well as the posterior tibial muscle. Computed tomography images of spiral fractures of the tibia show details of damage that are otherwise invisible on standard radiographs. Moreover, CT images provide useful information about the spatial location of the bone chips as well as possible threats to soft tissues that surround the fracture site. Every spiral fracture of the tibia is associated with disruption of the periosteum. 1. Computed tomography images of spiral fractures of the tibia show details of damage otherwise invisible on standard radiographs, 2. The sharp end of the distal tibial chip can damage the tibialis posterior muscle, long flexor muscles of the toes and the flexor hallucis longus, 3. Every spiral fracture of the tibia is associated with disruption of the periosteum.

  15. Fibrocartilage associated with human tendons and their pulleys.

    PubMed Central

    Benjamin, M; Qin, S; Ralphs, J R

    1995-01-01

    The presence of fibrocartilage in tendons that wrap around bony or fibrous pulleys is well known. It is an adaptation to resisting compression or shear, but the extent to which the structure of most human tendons is modified where they contact pulleys is less clear, for there has been no single comprehensive survey of a large number of sites. Less is known of the structure of the corresponding pulleys. In the present study, 38 regions of tendons that wrap around bony pulleys or pass beneath fibrous retinacula have been studied in routine histology sections taken from each of 2 or 3 elderly dissecting room cadavers. Most of the corresponding pulleys have also been examined. Fibrocartilage was present in 22 of the 38 tendon sites and it was most conspicuous where the tendons pressed predominantly against bone rather than retinacula and where they showed a large change in direction. Fibrocartilage was more characteristic of tendons at the ankle than the wrist, probably because the long axis of the foot is at right angles to that of the leg. There was considerable variation in the structure of tendon fibrocartilage. The most fibrocartilaginous tendons had oval or round cells embedded in a highly metachromatic matrix with interwoven or spiralling collagen fibres. At other sites, fibrocartilage cells were arranged in rows between parallel collagen fibres. The differences probably relate to differences in development. A single tendon could be modified at successive points along its length and fibrocartilage could be present in the endotenon and epitenon as well as in the tendon itself. Pathological changes seen in 'wrap around' tendons were fragmentation and partial delamination of the compressed surface, chondrocyte clustering, fatty infiltration and bone formation. Three types of pulleys were described for tendons--bony prominences and grooves, fibrous retinacula and synovial joints. The extent of cartilaginous differentiation on the periosteum of bony pulleys

  16. Achilles Tendon Rupture: Avoiding Tendon Lengthening during Surgical Repair and Rehabilitation

    PubMed Central

    Maquirriain, Javier

    2011-01-01

    Achilles tendon rupture is a serious injury for which the best treatment is still controversial. Its primary goal should be to restore normal length and tension, thus obtaining an optimal function. Tendon elongation correlates significantly with clinical outcome; lengthening is an important cause of morbidity and may produce permanent functional impairment. In this article, we review all factors that may influence the repair, including the type of surgical technique, suture material, and rehabilitation program, among many others. PMID:21966048

  17. The revitalisation of flexor tendon allografts with bone marrow stromal cells and mechanical stimulation: An ex vivo model revitalising flexor tendon allografts.

    PubMed

    Wu, J H; Thoreson, A R; Gingery, A; An, K N; Moran, S L; Amadio, P C; Zhao, C

    2017-03-01

    The present study describes a novel technique for revitalising allogenic intrasynovial tendons by combining cell-based therapy and mechanical stimulation in an ex vivo canine model. Specifically, canine flexor digitorum profundus tendons were used for this study and were divided into the following groups: (1) untreated, unprocessed normal tendon; (2) decellularised tendon; (3) bone marrow stromal cell (BMSC)-seeded tendon; and (4) BMSC-seeded and cyclically stretched tendon. Lateral slits were introduced on the tendon to facilitate cell seeding. Tendons from all four study groups were distracted by a servohydraulic testing machine. Tensile force and displacement data were continuously recorded at a sample rate of 20 Hz until 200 Newton of force was reached. Before testing, the cross-sectional dimensions of each tendon were measured with a digital caliper. Young's modulus was calculated from the slope of the linear region of the stress-strain curve. The BMSCs were labeled for histological and cell viability evaluation on the decellularized tendon scaffold under a confocal microscope. Gene expression levels of selected extracellular matrix tendon growth factor genes were measured. Results were reported as mean ± SD and data was analyzed with one-way ANOVAs followed by Tukey's post hoc multiple-comparison test. We observed no significant difference in cross-sectional area or in Young's modulus among the four study groups. In addition, histological sections showed that the BMSCs were aligned well and viable on the tendon slices after two-week culture in groups three and four. Expression levels of several extracellular matrix tendon growth factors, including collagen type I, collagen type III, and matrix metalloproteinase were significantly higher in group four than in group three (p < 0.05). Lateral slits introduced into de-cellularised tendon is a promising method of delivery of BMSCs without compromising cell viability and tendon mechanical properties. In addition

  18. Shear load transfer in high and low stress tendons.

    PubMed

    Kondratko-Mittnacht, Jaclyn; Duenwald-Kuehl, Sarah; Lakes, Roderic; Vanderby, Ray

    2015-05-01

    Tendon is an integral part of joint movement and stability, as it functions to transmit load from muscle to bone. It has an anisotropic, fibrous hierarchical structure that is generally loaded in the direction of its fibers/fascicles. Internal load distributions are altered when joint motion rotates an insertion site or when local damage disrupts fibers/fascicles, potentially causing inter-fiber (or inter-fascicular) shear. Tendons with different microstructures (helical versus linear) may redistribute loads differently. This study explored how shear redistributes axial loads in rat tail tendon (low stress tendons with linear microstructure) and porcine flexor tendon (high stress with helical microstructure) by creating lacerations on opposite sides of the tendon, ranging from about 20% to 60% of the tendon width, to create various magnitudes of shear. Differences in fascicular orientation were quantified using polarized light microscopy. Unexpectedly, both tendon types maintained about 20% of pre-laceration stress values after overlapping cuts of 60% of tendon width (no intact fibers end to end) suggesting that shear stress transfer can contribute more to overall tendon strength and stiffness than previously reported. All structural parameters for both tendon types decreased linearly with increasing laceration depth. The tail tendon had a more rapid decline in post-laceration elastic stress and modulus parameters as well as a more linear and less tightly packed fascicular structure, suggesting that positional tendons may be less well suited to redistribute loads via a shear mechanism. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Shear Load Transfer in High and Low Stress Tendons

    PubMed Central

    Kondratko-Mittnacht, Jaclyn; Duenwald-Kuehl, Sarah; Lakes, Roderic; Vanderby, Ray

    2016-01-01

    Background Tendon is an integral part of joint movement and stability, as it functions to transmit load from muscle to bone. It has an anisotropic, fibrous hierarchical structure that is generally loaded in the direction of its fibers/fascicles. Internal load distributions are altered when joint motion rotates an insertion site or when local damage disrupts fibers/fascicles, potentially causing inter-fiber (or inter-fascicular) shear. Tendons with different microstructure (helical versus linear) may redistribute loads differently. Method of Approach This study explored how shear redistributes axial loads in rat tail tendon (low stress tendons with linear microstructure) and porcine flexor tendon (high stress with helical microstructure) by creating lacerations on opposite sides of the tendon, ranging from about 20-60% of the tendon width, to create various magnitudes of shear. Differences in fascicular orientation were quantified using polarized light microscopy. Results and Conclusions Unexpectedly, both tendon types maintained about 20% of pre-laceration stress values after overlapping cuts of 60% of tendon width (no intact fibers end to end) suggesting that shear stress transfer can contribute more to overall tendon strength and stiffness than previously reported. All structural parameters for both tendon types decreased linearly with increasing laceration depth. The tail tendon had a more rapid decline in post-laceration elastic stress and modulus parameters as well as a more linear and less tightly packed fascicular structure, suggesting that positional tendons may be less well suited to redistribute loads via a shear mechanism. PMID:25700261

  20. Matrix metabolism rate differs in functionally distinct tendons.

    PubMed

    Birch, Helen L; Worboys, Sarah; Eissa, Sabry; Jackson, Brendan; Strassburg, Sandra; Clegg, Peter D

    2008-04-01

    Tendon matrix integrity is vital to ensure adequate mechanical properties for efficient function. Although historically tendon was considered to be relatively inert, recent studies have shown that tendon matrix turnover is active. During normal physiological activities some tendons are subjected to stress and strains much closer to their failure properties than others. Tendons with low safety margins are those which function as energy stores such as the equine superficial digital flexor tendon (SDFT) and human Achilles tendon (AT). We postulate therefore that energy storing tendons suffer a higher degree of micro-damage and thus have a higher rate of matrix turnover than positional tendons. The hypothesis was tested using tissue from the equine SDFT and common digital extensor tendon (CDET). Matrix turnover was assessed indirectly by a combination of measurements for matrix age, markers of degradation, potential for degradation and protein expression. Results show that despite higher cellularity, the SDFT has lower relative levels of mRNA for collagen types I and III. Non-collagenous proteins, although expressed at different levels per cell, do not appear to differ between tendon types. Relative levels of mRNA for MMP1, MMP13 and both pro-MMP3 and MMP13 protein activity were significantly higher in the CDET. Correspondingly levels of cross-linked carboxyterminal telopeptide of type I collagen (ICTP) were higher in the CDET and tissue fluorescence lower suggesting more rapid turnover of the collagenous component. Reduced or inhibited collagen turnover in the SDFT may account for the high level of degeneration and subsequent injury compared to the CDET.

  1. Evaluating Changes in Tendon Crimp with Fatigue Loading as an ex vivo Structural Assessment of Tendon Damage

    PubMed Central

    Freedman, Benjamin R.; Zuskov, Andrey; Sarver, Joseph J.; Buckley, Mark R.; Soslowsky, Louis J.

    2015-01-01

    The complex structure of tendons relates to their mechanical properties. Previous research has associated the waviness of collagen fibers (crimp) during quasi-static tensile loading to tensile mechanics, but less is known about the role of fatigue loading on crimp properties. In this study (IACUC approved), mouse patellar tendons were fatigue loaded while an integrated plane polariscope simultaneously assessed crimp properties. We demonstrate a novel structural mechanism whereby tendon crimp amplitude and frequency are altered with fatigue loading. In particular, fatigue loading increased the crimp amplitude across the tendon width and length, and these structural alterations were shown to be both region and load dependent. The change in crimp amplitude was strongly correlated to mechanical tissue laxity (defined as the ratio of displacement and gauge length relative to the first cycle of fatigue loading assessed at constant load throughout testing), at all loads and regions evaluated. Together, this study highlights the role of fatigue loading on tendon crimp properties as a function of load applied and region evaluated, and offers an additional structural mechanism for mechanical alterations that may lead to ultimate tendon failure. PMID:25773654

  2. [Anterior dislocation of the popliteus tendon].

    PubMed

    Martinez Molina, Oscar

    2009-01-01

    Review the most relevant aspects of the posterolateral corner anatomy of the knee, based on the analysis of papers that throughout the years have made important contributions to the knowledge of these structures. Last et al rejected the idea that the popliteal tendon is an isolated structure, suggesting rather that its variants are closely linked to other anatomical structures. The studies by Tria et al contributed the features of the tendon as it attaches to the lateral condyle, just to mention a couple of examples. This is the case of a 48 year-old female patient with a knee injury caused by an external rotation mechanism. Clinical features included pain, a protruding sensation in the lateral aspect of the knee, and voluntary pseudoblocking resulting from external rotation maneuvers. Knee arthroscopy was performed and dislocation of the popliteal tendon anterior to the lateral condyle was diagnosed, besides a longitudinal tear. The tendon was repositioned, radiofrequency was applied to both the tendon and the popliteal hiatus, and the former was kept in place with a plaster cast worn for 6 weeks. Even though the isolated tear or avulsion of the tendon has already been reported, the dislocation or instability of the popliteal tendon as it relates to the lateral femoral condyle has apparently not been approached yet. As we did in this case, other authors have also confirmed the diagnosis arthroscopically, Naver in 1985, Rose in 1988, and Burstein in 1990.

  3. Minimally invasive reconstruction of chronic achilles tendon ruptures using the ipsilateral free semitendinosus tendon graft and interference screw fixation.

    PubMed

    Maffulli, Nicola; Loppini, Mattia; Longo, Umile Giuseppe; Maffulli, Gayle D; Denaro, Vincenzo

    2013-05-01

    Achilles tendon ruptures represent more than 40% of all tendon ruptures requiring surgical management. About 20% of acute Achilles tendon tears are not diagnosed at the time of injury and become chronic, necessitating more complicated management than fresh injuries. Several techniques for the reconstruction of chronic tears of the Achilles tendon have been described, but the superiority of one technique over the others has not been demonstrated. Mini-invasive reconstruction of the Achilles tendon, with a gap lesion larger than 6 cm, using the ipsilateral free semitendinosus tendon graft will result in improvement of the overall function with a low rate of complications. Case series; Level of evidence, 4. Between 2008 and 2010, the authors prospectively enrolled 28 consecutive patients (21 men and 7 women; median age, 46 years) with chronic closed ruptures of the Achilles tendon who had undergone reconstruction with a free semitendinosus tendon graft. They assessed the Achilles tendon Total Rupture Score (ATRS), maximum calf circumference, and isometric plantarflexion strength before surgery and at the last follow-up. Outcome of surgery and rate of complications were also recorded. The median follow-up after surgery was 31.4 months. The overall result of surgery was excellent/good in 26 (93%) of 28 patients. The ATRS improved from 42 (range, 29-55) to 86 (range, 78-95) (P < .0001). In the operated leg, the maximum calf circumference and isometric plantarflexion strength were significantly improved after surgery (P < .0001); however, their values remained significantly lower than those of the opposite side (P < .0001). All patients were able to walk on tiptoes and returned to their preinjury working occupation. No infections were recorded. Mini-invasive reconstruction of the Achilles tendon, with a gap lesion larger than 6 cm, using the ipsilateral free semitendinosus tendon graft provides a significant improvement of symptoms and function, although calf

  4. Reconstruction of a ruptured patellar tendon using ipsilateral semitendinosus and gracilis tendons with preserved distal insertions: two case reports

    PubMed Central

    2013-01-01

    Background Acute patellar tendon ruptures with poor tissue quality. Ruptures that have been neglected are difficult to repair. Several surgical techniques for the repair of the patellar tendon have been reported, however, these techniques remain difficult because of contractures, adhesions, and atrophy of the quadriceps muscle after surgery. Case presentation We report the cases of 2 Japanese patients (Case 1: a 16-year-old male and Case 2: a 43-year-old male) with patellar tendon ruptures who were treated by reconstruction using semitendinosus-gracilis (STG) tendons with preserved distal insertions. Retaining the original insertion of the STG appears to preserve its viability and provide the revascularization necessary to accelerate healing. Both tendons were placed in front of the patella, in a figure-of-eight fashion, providing stability to the patella. Conclusion Both patients recovered near normal strength and stability of the patellar tendon as well as restoration of function after the operation. PMID:24010848

  5. Using the zebrafish to understand tendon development and repair

    PubMed Central

    Chen, Jessica W.; Galloway, Jenna L.

    2017-01-01

    Tendons are important components of our musculoskeletal system. Injuries to these tissues are very common, resulting from occupational-related injuries, sports-related trauma, and age-related degeneration. Unfortunately, there are few treatment options, and current therapies rarely restore injured tendons to their original function. An improved understanding of the pathways regulating their development and repair would have significant impact in stimulating the formulation of regenerative-based approaches for tendon injury. The zebrafish provides an ideal system in which to perform genetic and chemical screens to identify new pathways involved in tendon biology. Until recently, there had been few descriptions of tendons and ligaments in the zebrafish and their similarity to mammalian tendon tissues. In this chapter, we describe the development of the zebrafish tendon and ligament tissues in the context of their gene expression, structure, and interactions with neighboring musculoskeletal tissues. We highlight the similarities with tendon development in higher vertebrates, showing that the craniofacial tendons and ligaments in zebrafish morphologically, molecularly, and structurally resemble mammalian tendons and ligaments from embryonic to adult stages. We detail methods for fluorescent in situ hybridization and immunohistochemistry as an assay to examine morphological changes in the zebrafish musculoskeleton. Staining assays such as these could provide the foundation for screen-based approaches to identify new regulators of tendon development, morphogenesis, and repair. These discoveries would provide new targets and pathways to study in the context of regenerative medicine-based approaches to improve tendon healing. PMID:28129848

  6. An Overview of the Management of Flexor Tendon Injuries

    PubMed Central

    Griffin, M; Hindocha, S; Jordan, D; Saleh, M; Khan, W

    2012-01-01

    Flexor tendon injuries still remain a challenging condition to manage to ensure optimal outcome for the patient. Since the first flexor tendon repair was described by Kirchmayr in 1917, several approaches to flexor tendon injury have enabled successful repairs rates of 70-90%. Primary surgical repair results in better functional outcome compared to secondary repair or tendon graft surgery. Flexor tendon injury repair has been extensively researched and the literature demonstrates successful repair requires minimal gapping at the repair site or interference with tendon vascularity, secure suture knots, smooth junction of tendon end and having sufficient strength for healing. However, the exact surgical approach to achieve success being currently used among surgeons is still controversial. Therefore, this review aims to discuss the results of studies demonstrating the current knowledge regarding the optimal approach for flexor tendon repair. Post-operative rehabilitation for flexor tendon surgery is another area, which has caused extensive debate in hand surgery. The trend to more active mobilisation protocols seems to be favoured but further study in this area is needed to find the protocol, which achieves function and gliding but avoids rupture of the tendons. Lastly despite success following surgery complications commonly still occur post surgery, including adhesion formation, tendon rupture and stiffness of the joints. Therefore, this review aims to discuss the appropriate management of these difficulties post surgery. New techniques in management of flexor tendon will also be discussed including external laser devices, addition of growth factors and cytokines. PMID:22431948

  7. Effect of elbow and forearm position on contact pressure between the extensor origin and the lateral side of the capitellum.

    PubMed

    Tanaka, Yoshitaka; Aoki, Mitsuhiro; Izumi, Tomoki; Wada, Takuro; Fujimiya, Mineko; Yamashita, Toshihiko

    2011-01-01

    Bone-to-tendon contact in the origin of the common extensor tendons is considered to be one of the causes of lateral epicondylitis. Some factors, including elbow and forearm position, varus stress to the elbow, or contraction of the wrist extensor tendons, are considered to affect this bone-to-tendon contact. However, no studies have evaluated the effect of the elbow and forearm position on bone-tendon interface. The purpose of this study is to evaluate the effect of the position of the elbow and forearm on the contact pressure of the tendinous origin of the common wrist and finger extensors. We used 8 fresh cadaveric upper extremities. Contact pressure between the origin of the common extensor tendons and the lateral side of the capitellum was measured with a pressure sensor and was compared among various conditions, including elbow flexion angle (0°, 30°, 60°, and 90°), forearm rotation position (neutral and 81.5° pronation position), and varus stress load of the elbow (none, gravity on the forearm, and gravity on the forearm +1.96 Nm). Contact pressure was also measured during tension force of the extensor carpi radialis longus, extensor carpi radialis brevis, and extensor digitorum communis by 0, 9.8, and 19.6 N. Contact pressure was significantly increased with the elbow extension position, forearm pronation position, and varus stress to the elbow under tension of the extensor carpi radialis longus or extensor carpi radialis brevis. This study provides data about the amount of contact pressure between bone and tendon at the origin of the common extensor tendons in the elbow. This information may lead to a better understanding of, and better treatment for, lateral epicondylitis. Copyright © 2011. Published by Elsevier Inc.

  8. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Passive tendon prosthesis. 888.3025 Section 888...) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3025 Passive tendon prosthesis. (a) Identification. A passive tendon prosthesis is a device intended to be implanted made of silicon elastomer or a...

  9. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Passive tendon prosthesis. 888.3025 Section 888...) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3025 Passive tendon prosthesis. (a) Identification. A passive tendon prosthesis is a device intended to be implanted made of silicon elastomer or a...

  10. [Results of flexor tendon sutures of the fingers with 2-strand (40 tendons) and 4-strand (64 tendons) core sutures].

    PubMed

    Winkel, R; Kalbhenn, O; Hoffmann, R

    2012-06-01

    This retrospective examination compares the results of finger flexor tendon sutures with 2 strands and 4 strands. It was checked, whether and how 2 more strands influenced the rupture rate, the movement of the finger and the contentment of the patients. From 1996 to 2000 for the core suture of the flexor tendon of fingers we used 2 strands. 35 patients with 40 tendon sutures of 73 patients were examined. From 2001 to 2005 we used for the core suture 2 loop threads. 53 patients with 64 tendon sutures from a total of 111 patients were examined. At least 12 months had passed between operation and the examination. The rupture rate and the range of movement of each finger joint and the total mobility of the affected fingers were evaluated. Each case was compared to the uninjured opposite hand. The functional result was judged according to the score of Buck-Gramcko. The patient's contentment was recorded by the DASH (disability of arm, shoulder and hand) score. Effects of gender, age, accompanying injuries, zone of the injury and their influence on the results were analysed. The Buck-Gramcko score showed in the 2-strand group a distribution from summarised 70% "excellent" and "good" and 30% "fair" and "poor". In the 4-strand-group the relation was 93.7% "excellent" and "good", 6.3% "fair", one "poor". In the 2-strand group 2/40 (5%) of the tendon sutures ruptured, in the 4-strand group 1/64 (1.6%) ruptured. The average DASH value in the 2-strands-group was 16.6/100, in the 4-strands-group 18.1/100 when 0 is the best possible result and 100 the worst. The patient judgement in the 2-strand group was summarised to 70% for "excellent" and "good" and 30% "fair" and "poor". In the 4-strand group the patient's judgment was summarised in 75% "excellent" and "good" and in 25% "fair". The results of flexor tendon sutures with 4-strand core sutures have been superior to the results with 2-strand core suture according to range of motion of the fingers (P <0.005). © Georg Thieme

  11. Augmented Repair of an Achilles Tendon Rupture Using the Flexor Digitorum Lateralis Tendon in a Toy Poodle.

    PubMed

    Katayama, Masaaki

    2016-11-01

    To report appositional augmentation of Achilles tendon rupture in a toy breed dog with an intact flexor digitorum lateralis (FDL) muscle tendon. Clinical case report. Two-year-old spayed female Toy Poodle with Achilles tendon rupture. The Achilles tendon was accidentally ruptured by hair clippers during grooming. The dog demonstrated a plantigrade stance without digital flexion of the right hind limb. The ruptured gastrocnemius and superficial digital flexor tendons were sutured to their respective cut ends using a simple locking loop pattern under a surgical microscope. The repair site was appositionally augmented by the caudally retracted intact FDL. An aluminum splint was applied on the plantar aspect to immobilize the tarsal joint for the first 2 weeks, after which a soft bandage was applied for another 2 weeks. At the 7 month follow-up no lameness was detected during walking and no complications associated with decreased FDL function such as digital contracture were observed. The range of motion of the tarsal joint had improved and could be flexed to ∼60° and extended fully. Use of the FDL is feasible for augmenting Achilles tendon repair in toy breed dogs. © Copyright 2016 by The American College of Veterinary Surgeons.

  12. Clinical Sign for Missed Decompression of a Separate Extensor Pollicis Brevis Compartment in de Quervain's Disease.

    PubMed

    Benatar, Niels

    2017-08-01

    Persistent pain despite previous surgery for de Quervain's disease might be due to an overlooked septum between the abductor pollicis longus tendon slips and the extensor pollicis brevis tendon, or an overlooked completely separate compartment for the extensor pollicis brevis tendon alone. In both of these instances, extension of the MP joint of the thumb against resistance elicits pain at the distal level of the first extensor compartment of the wrist. When this sign is positive, revisional surgery and decompression of the remaining septum or separate compartment is indicated. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Bilateral Patellar Tendon Rupture.

    PubMed

    Kamienski, Mary

    The knee is the most complex and largest joint in the body. Injuries to any part of this joint affect the entire body. There are multiple injuries that can occur to the knee, with the most common being ligament and meniscus tears. A not-so-common injury to the knee is a patellar tendon rupture. A bilateral patellar tendon rupture is extremely rare. A case study of a 43-year-old man who sustained a bilateral patellar tendon rupture while playing softball is used to present this devastating injury. This discussion includes the incidence and diagnosis of the tear, surgical repair, as well as a description of the comprehensive rehabilitation process necessary to allow the patient to return to normal physical activity. Risks and complications of this surgery and the expected outcomes are also presented.

  14. Robot Arm with Tendon Connector Plate and Linear Actuator

    NASA Technical Reports Server (NTRS)

    Bridgwater, Lyndon (Inventor); Millerman, Alexander (Inventor); Ihrke, Chris A. (Inventor); Diftler, Myron A. (Inventor); Nguyen, Vienny (Inventor)

    2014-01-01

    A robotic system includes a tendon-driven end effector, a linear actuator, a flexible tendon, and a plate assembly. The linear actuator assembly has a servo motor and a drive mechanism, the latter of which translates linearly with respect to a drive axis of the servo motor in response to output torque from the servo motor. The tendon connects to the end effector and drive mechanism. The plate assembly is disposed between the linear actuator assembly and the tendon-driven end effector and includes first and second plates. The first plate has a first side that defines a boss with a center opening. The second plate defines an accurate through-slot having tendon guide channels. The first plate defines a through passage for the tendon between the center opening and a second side of the first plate. A looped end of the flexible tendon is received within the tendon guide channels.

  15. [Flexor tendon repair: a short story].

    PubMed

    Moutet, F; Corcella, D; Forli, A; Mesquida, V

    2014-12-01

    This short story of flexor tendon repair aims to illustrate hesitations and wanderings of this surgery. Obviously tendon repair was very early considered, but it developed and diffused rather lately. It became a routine practice only in 20th century. This was due on the one hand, in Occident, to the Galen's dogmatic interdiction, on the other hand, to the repair difficulties of this paradoxical structure. Actually tendon is made of fibroblasts and collagen (sticky substances), and then its only goal is to move. According to this necessity, whatever the used techniques are, gliding is the final purpose. Technical evolutions are illustrated by historical contributions to flexor tendon surgery of several "giants" of hand surgery. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  16. Effect of Tendon Stem Cells in Chitosan/β-Glycerophosphate/Collagen Hydrogel on Achilles Tendon Healing in a Rat Model.

    PubMed

    Yang, Zhijin; Cao, Honghui; Gao, Shang; Yang, Mingyu; Lyu, Jingtong; Tang, Kanglai

    2017-09-27

    BACKGROUND The aim of this study was to determine whether the local application of tendon stem cells (TSCs) with chitosan/β-glycerophosphate/collagen(C/GP/Co) hydrogel promotes healing after an acute Achilles tendon injury in a rat model. MATERIAL AND METHODS Ninety-six Sprague-Dawley (SD) rats were used to make an Achilles tendon defect model, then the animals were randomly divided into 4 groups consisting of 8 rats each: control group, hydrogel group, TSCs group, and TSCs with hydrogel group. At 2, 4, and 6 weeks after treatment, tendon samples were harvested, and the quality of tendon repair was evaluated based on histology, immunohistochemistry, and biomechanical properties. RESULTS Combining TSCs with C/GP/Co hydrogel significantly enhances tendon healing compared with the control, hydrogel, and TSCs groups. The improved healing was indicated by the improvement in histological and immunohistochemistry outcomes and the increase in the biomechanical properties of the regenerated tissue at both 4 and 6 weeks post-injury. CONCLUSIONS This study demonstrates that the transplantation of TSCs combined with C/GP/Co hydrogel significantly improved the histological, immunohistochemistry, and biomechanical outcomes of the regenerated tissue at 4 and 6 weeks after implantation. TSCs with C/GP/Co hydrogel is a potentially effective treatment for tendon injury.

  17. New Developments Are Improving Flexor Tendon Repair.

    PubMed

    Tang, Jin Bo

    2018-06-01

    New developments in primary tendon repair in recent decades include stronger core tendon repair techniques, judicious and adequate venting of critical pulleys, followed by a combination of passive and active digital flexion and extension. During repair, core sutures over the tendon should have sufficient suture purchase (no shorter than 0.7 to 1 cm) in each tendon end and must be sufficiently tensioned to resist loosening and gap formation between tendon ends. Slight or even modest bulkiness in the tendon substance at the repair site is not harmful, although marked bulkiness should always be avoided. To expose the tendon ends and reduce restriction to tendon gliding, the longest annular pulley in the fingers (i.e., the A2 pulley) can be vented partially with an incision over its distal or proximal sheath no longer than 1.5 to 2 cm; the annular pulley over the middle phalanx (i.e., the A4 pulley) can be vented entirely. Surgeons have not observed adverse effects on hand function after judicious and limited venting. The digital extension-flexion test to check the quality of the repair during surgery has become increasingly routine. A wide-awake surgical setting allows patient to actively move the digits. After surgery, surgeons and therapists protect patients with a short splint and flexible wrist positioning, and are now moving toward out-of-splint freer early active motion. Improved outcomes have been reported over the past decade with minimal or no rupture during postoperative active motion, along with lower rates of tenolysis.

  18. Rotator cuff tendon connections with the rotator cable.

    PubMed

    Rahu, Madis; Kolts, Ivo; Põldoja, Elle; Kask, Kristo

    2017-07-01

    The literature currently contains no descriptions of the rotator cuff tendons, which also describes in relation to the presence and characteristics of the rotator cable (anatomically known as the ligamentum semicirculare humeri). The aim of the current study was to elucidate the detailed anatomy of the rotator cuff tendons in association with the rotator cable. Anatomic dissection was performed on 21 fresh-frozen shoulder specimens with an average age of 68 years. The rotator cuff tendons were dissected from each other and from the glenohumeral joint capsule, and the superior glenohumeral, coracohumeral, coracoglenoidal and semicircular (rotator cable) ligaments were dissected. Dissection was performed layer by layer and from the bursal side to the joint. All ligaments and tendons were dissected in fine detail. The rotator cable was found in all specimens. It was tightly connected to the supraspinatus (SSP) tendon, which was partly covered by the infraspinatus (ISP) tendon. The posterior insertion area of the rotator cable was located in the region between the middle and inferior facets of the greater tubercle of the humerus insertion areas for the teres minor (TM), and ISP tendons were also present and fibres from the SSP extended through the rotator cable to those areas. The connection between the rotator cable and rotator cuff tendons is tight and confirms the suspension bridge theory for rotator cuff tears in most areas between the SSP tendons and rotator cable. In its posterior insertion area, the rotator cable is a connecting structure between the TM, ISP and SSP tendons. These findings might explain why some patients with relatively large rotator cuff tears can maintain seamless shoulder function.

  19. Relationship between tendon stiffness and failure: a metaanalysis

    PubMed Central

    LaCroix, Andrew S.; Duenwald-Kuehl, Sarah E.; Lakes, Roderic S.

    2013-01-01

    Tendon is a highly specialized, hierarchical tissue designed to transfer forces from muscle to bone; complex viscoelastic and anisotropic behaviors have been extensively characterized for specific subsets of tendons. Reported mechanical data consistently show a pseudoelastic, stress-vs.-strain behavior with a linear slope after an initial toe region. Many studies report a linear, elastic modulus, or Young's modulus (hereafter called elastic modulus) and ultimate stress for their tendon specimens. Individually, these studies are unable to provide a broader, interstudy understanding of tendon mechanical behavior. Herein we present a metaanalysis of pooled mechanical data from a representative sample of tendons from different species. These data include healthy tendons and those altered by injury and healing, genetic modification, allograft preparation, mechanical environment, and age. Fifty studies were selected and analyzed. Despite a wide range of mechanical properties between and within species, elastic modulus and ultimate stress are highly correlated (R2 = 0.785), suggesting that tendon failure is highly strain-dependent. Furthermore, this relationship was observed to be predictable over controlled ranges of elastic moduli, as would be typical of any individual species. With the knowledge gained through this metaanalysis, noninvasive tools could measure elastic modulus in vivo and reasonably predict ultimate stress (or structural compromise) for diseased or injured tendon. PMID:23599401

  20. The use of Achilles tendon allograft for latissimus dorsi tendon reconstruction: a minimally invasive technique.

    PubMed

    Sabzevari, Soheil; Chao, Tom; Kalawadia, Jay; Lin, Albert

    2018-01-01

    Treatment of subacute, retracted latissimus dorsi and teres major tendon ruptures in young overhead athletes is challenging. This case report describes management of a subacute retracted latissimus dorsi and teres major rupture with Achilles tendon allograft reconstruction using a two-incision minimally invasive technique. Level of evidence V.

  1. [Conservative functional treatment of Achilles tendon ruptures].

    PubMed

    Hüfner, T; Gaulke, R; Imrecke, J; Krettek, C; Stübig, T

    2010-09-01

    The conservative functional treatment of Achilles tendon ruptures has developed further over the last 20 years and is basically possible for 60-80% of patients. The treatment leads to success if the indications obtained by dynamic sonography are correctly interpreted (adaptation of the tendon ends up to 20 degrees plantar flexion), if the patient presents sufficient compliance and the physiotherapy is increasingly intensified depending on tendon healing. Modern ortheses allow an increased equinus position and therefore improved protection of the healing tendon. If these factors are present a relatively low re-rupture rate of only 7% can be achieved. The decisive advantage of conservative functional therapy is the avoidance of specific operative risks, such as infection and injury to the sural nerve. After removal of the orthesis the tendon should continue to be modeled using shoe insoles and raised heels.

  2. Position Control of Tendon-Driven Fingers

    NASA Technical Reports Server (NTRS)

    Abdallah, Muhammad E.; Platt, Robert, Jr.; Hargrave, B.; Pementer, Frank

    2011-01-01

    Conventionally, tendon-driven manipulators implement some force control scheme based on tension feedback. This feedback allows the system to ensure that the tendons are maintained taut with proper levels of tensioning at all times. Occasionally, whether it is due to the lack of tension feedback or the inability to implement sufficiently high stiffnesses, a position control scheme is needed. This work compares three position controllers for tendon-driven manipulators. A new controller is introduced that achieves the best overall performance with regards to speed, accuracy, and transient behavior. To compensate for the lack of tension feedback, the controller nominally maintains the internal tension on the tendons by implementing a two-tier architecture with a range-space constraint. These control laws are validated experimentally on the Robonaut-2 humanoid hand. I

  3. Is the chronic painful tendinosis tendon a strong tendon?: a case study involving an Olympic weightlifter with chronic painful Jumper's knee.

    PubMed

    Gisslén, Karl; Ohberg, Lars; Alfredson, Håkan

    2006-09-01

    The chronic painful tendinosis tendon is generally considered a degenerated and weak tendon. However, this has not been scientifically verified, and is to be considered a hypothesis. We present here a case study involving a high-level Olympic weightlifter with chronic painful patellar tendinosis who started heavy-weight training very early after successful treatment with sclerosing injections. A 25-year-old super heavy-weight (+105 kg) Olympic weightlifter with 9 months duration of severe pain (prohibiting full training) in the proximal patellar tendon, where ultrasound and Doppler showed a widened tendon with structural changes and neovascularisation, was given one treatment with ultrasound and Doppler-guided injections of the sclerosing agent polidocanol. The injections targeted the neovessels posterior to the tendon. The patient was pain-free after the treatment, and already after 2-weeks he started with heavy-weight training (240 kg in deep squats) to try to qualify for the Olympics. Additional very heavy training on training camps, most often without having any discomfort or pain in the patellar tendon, resulted in Swedish records and ninth place at the European Championships 17 weeks after the treatment. Despite beating the national records, he did not qualify for the Olympics. Ultrasound and Doppler follow-ups have shown only a few remaining neovessels, and little structural tendon changes. This case questions previous theories about the weak tendinosis tendon, and stresses the importance of studies evaluating tendon strength.

  4. Uncovering the cellular and molecular changes in tendon stem/progenitor cells attributed to tendon aging and degeneration.

    PubMed

    Kohler, Julia; Popov, Cvetan; Klotz, Barbara; Alberton, Paolo; Prall, Wolf Christian; Haasters, Florian; Müller-Deubert, Sigrid; Ebert, Regina; Klein-Hitpass, Ludger; Jakob, Franz; Schieker, Matthias; Docheva, Denitsa

    2013-12-01

    Although the link between altered stem cell properties and tissue aging has been recognized, the molecular and cellular processes of tendon aging have not been elucidated. As tendons contain stem/progenitor cells (TSPC), we investigated whether the molecular and cellular attributes of TSPC alter during tendon aging and degeneration. Comparing TSPC derived from young/healthy (Y-TSPC) and aged/degenerated human Achilles tendon biopsies (A-TSPC), we observed that A-TSPC exhibit a profound self-renewal and clonogenic deficits, while their multipotency was still retained. Senescence analysis showed a premature entry into senescence of the A-TSPC, a finding accompanied by an upregulation of p16(INK4A). To identify age-related molecular factors, we performed microarray and gene ontology analyses. These analyses revealed an intriguing transcriptomal shift in A-TSPC, where the most differentially expressed probesets encode for genes regulating cell adhesion, migration, and actin cytoskeleton. Time-lapse analysis showed that A-TSPC exhibit decelerated motion and delayed wound closure concomitant to a higher actin stress fiber content and a slower turnover of actin filaments. Lastly, based on the expression analyses of microarray candidates, we suggest that dysregulated cell-matrix interactions and the ROCK kinase pathway might be key players in TSPC aging. Taken together, we propose that during tendon aging and degeneration, the TSPC pool is becoming exhausted in terms of size and functional fitness. Thus, our study provides the first fundamental basis for further exploration into the molecular mechanisms behind tendon aging and degeneration as well as for the selection of novel tendon-specific therapeutical targets. © 2013 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  5. [Tendinosis and ruptures of the Achilles tendon].

    PubMed

    Amlang, M H; Zwipp, H

    2012-02-01

    Tendinosis of the Achilles tendon is a degenerative-reparative structural change of the tendon with microdefects, increases in cross-section due to cicatricial tendon regeneration, neoangiogenesis and reduction of elasticity. The previously used term tendinitis is only rarely used for the chronic form since signs of inflammation such as redness and hyperthermia or elevated levels of inflammatory parameters on laboratory testing are generally absent. Duplex sonography with visualization of the neovascularization has become a valuable supplement not only for diagnostics but also for therapy planning. The classic, conservative therapy for painful tendinosis consists of oral anti-inflammatory drugs, pain-adapted load reduction, raising the heel, stretching the calf musculature, and various physiotherapeutic interventions. When conservative treatment over a period of 4 - 6 months fails to produce any or non-adequate pain relief, an indication for surgical treatment should be considered. In the therapy for fresh ruptures of the Achilles tendon further developments in minimally invasive techniques have led to a worldwide paradigm change over the past 10 years. The decisive advantage of minimally invasive surgical techniques is the lower risk of wound infection as compared to the sutures of the open technique. When compared with conservative functional therapy the minimally invasive repair has the advantage of being less dependent on the compliance of the patient since, in the early phase of tendon healing the suture prevents a separation of the tendon ends upon controlled movements. However, not every patient with a ruptured Achilles tendon should be treated with a minimally invasive repair. Open tendon reconstruction and functional conservative therapy are still justified when the correct indication is given. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Cell phenotypic variation in normal and damaged tendons

    PubMed Central

    Clegg, Peter D; Strassburg, Sandra; Smith, Roger K

    2007-01-01

    Injuries to tendons are common in both human athletes as well as in animals, such as the horse, which are used for competitive purposes. Furthermore, such injuries are also increasing in prevalence in the ageing, sedentary population. Tendon diseases often respond poorly to treatment and require lengthy periods of rehabilitation. The tendon has a unique extracellular matrix, which has developed to withstand the mechanical demands of such tensile-load bearing structures. Following injury, any repair process is inadequate and results in tissue that is distinct from original tendon tissue. There is growing evidence for the key role of the tendon cell (tenocyte) in both the normal physiological homeostasis and regulation of the tendon matrix and the pathological derangements that occur in disease. In particular, the tenocyte is considered to have a major role in effecting the subclinical matrix degeneration that is thought to occur prior to clinical disease, as well as in the severe degradative events that occur in the tendon at the onset of clinical disease. Furthermore, the tenocyte is likely to have a central role in the production of the biologically inadequate fibrocartilaginous repair tissue that develops subsequent to tendinopathy. Understanding the biology of the tenocyte is central to the development of appropriate interventions and drug therapies that will either prevent the onset of disease, or lead to more rapid and appropriate repair of injured tendon. Central to this is a full understanding of the proteolytic response in the tendon in disease by such enzymes as metalloproteinases, as well as the control of the inappropriate fibrocartilaginous differentiation. Finally, it is important that we understand the role of both intrinsic and extrinsic cellular elements in the repair process in the tendon subsequent to injury. PMID:17696903

  7. Stem Cell Applications in Tendon Disorders: A Clinical Perspective

    PubMed Central

    Young, Mark

    2012-01-01

    Tendon injuries are a common cause of morbidity and a significant health burden on society. Tendons are structural tissues connecting muscle to bone and are prone to tearing and tendinopathy, an overuse or degenerative condition that is characterized by failed healing and cellular depletion. Current treatments, for tendon tear are conservative, surgical repair or surgical scaffold reconstruction. Tendinopathy is treated by exercises, injection therapies, shock wave treatments or surgical tendon debridement. However, tendons usually heal with fibrosis and scar tissue, which has suboptimal tensile strength and is prone to reinjury, resulting in lifestyle changes with activity restriction. Preclinical studies show that cell therapies have the potential to regenerate rather than repair tendon tissue, a process termed tenogenesis. A number of different cell lines, with varying degrees of differentiation, have being evaluated including stem cells, tendon derived cells and dermal fibroblasts. Even though cellular therapies offer some potential in treating tendon disorders, there have been few published clinical trials to determine the ideal cell source, the number of cells to administer, or the optimal bioscaffold for clinical use. PMID:22448174

  8. Force Model for Control of Tendon Driven Hands

    NASA Technical Reports Server (NTRS)

    Pena, Edward; Thompson, David E.

    1997-01-01

    Knowing the tendon forces generated for a given task such as grasping via a model, an artificial hand can be controlled. A two-dimensional force model for the index finger was developed. This system is assumed to be in static equilibrium, therefore, the equations of equilibrium were applied at each joint. Constraint equations describing the tendon branch connectivity were used. Gaussian elimination was used to solve for the unknowns of the Linear system. Results from initial work on estimating tendon forces in post-operative hands during active motion therapy were discussed. The results are important for understanding the effects of hand position on tendon tension, elastic effects on tendon tension, and overall functional anatomy of the hand.

  9. The role of animal models in tendon research

    PubMed Central

    Hast, M. W.; Zuskov, A.; Soslowsky, L. J.

    2014-01-01

    Tendinopathy is a debilitating musculoskeletal condition which can cause significant pain and lead to complete rupture of the tendon, which often requires surgical repair. Due in part to the large spectrum of tendon pathologies, these disorders continue to be a clinical challenge. Animal models are often used in this field of research as they offer an attractive framework to examine the cascade of processes that occur throughout both tendon pathology and repair. This review discusses the structural, mechanical, and biological changes that occur throughout tendon pathology in animal models, as well as strategies for the improvement of tendon healing. Cite this article: Bone Joint Res 2014;3:193–202. PMID:24958818

  10. The Achilles tendon: fundamental properties and mechanisms governing healing

    PubMed Central

    Freedman, Benjamin R.; Gordon, Joshua A.; Soslowsky, Louis J.

    2014-01-01

    Summary This review highlights recent research on Achilles tendon healing, and comments on the current clinical controversy surrounding the diagnosis and treatment of injury. The processes of Achilles tendon healing, as demonstrated through changes in its structure, composition, and biomechanics, are reviewed. Finally, a review of tendon developmental biology and mechano transductive pathways is completed to recognize recent efforts to augment injured Achilles tendons, and to suggest potential future strategies for therapeutic intervention and functional tissue engineering. Despite an abundance of clinical evidence suggesting that current treatments and rehabilitation strategies for Achilles tendon ruptures are equivocal, significant questions remain to fully elucidate the basic science mechanisms governing Achilles tendon injury, healing, treatment, and rehabilitation. PMID:25332943

  11. Intravoxel incoherent motion (IVIM) imaging in human achilles tendon.

    PubMed

    Wengler, Kenneth; Fukuda, Takeshi; Tank, Dharmesh; Huang, Mingqian; Gould, Elaine S; Schweitzer, Mark E; He, Xiang

    2018-05-09

    Limited microcirculation has been implicated in Achilles tendinopathy and may affect healing and disease progression. Existing invasive and noninvasive approaches to evaluate tendon microcirculation lack sensitivity and spatial coverage. To develop a novel Achilles tendon intravoxel incoherent motion (IVIM) MRI protocol to overcome the limitations from low tendon T 2 /T 2 * value and low intratendinous blood volume and blood velocity to evaluate tendon microcirculation. Prospective. Sixteen healthy male participants (age 31.0 ± 2.1) were recruited. A stimulated echo readout-segmented echo planar imaging (ste-RS-EPI) IVIM sequence at 3.0T. The feasibility of the proposed ste-RS-EPI IVIM protocol combined with Achilles tendon magic angle effect was evaluated. The sensitivity of the protocol was assessed by an exercise-induced intratendinous hemodynamic response in healthy participants. The vascular origin of the observed IVIM signal was validated by varying the diffusion mixing time and echo time. Two-tailed t-tests were used to evaluate differences (P < 0.05 was considered significant). Consistent with known tendon hypovascularity, the midportion Achilles tendon at baseline showed significantly lower IVIM-derived perfusion fraction (f p ) (3.1 ± 0.9%) compared to the proximal and distal Achilles tendon (6.0 ± 1.8% and 6.1 ± 2.0%, respectively; P < 0.01). Similarly, the midportion Achilles tendon exhibited significantly lower baseline blood flow index (D*×f p ) (40.9 ± 19.2, 18.3 ± 5.3, and 32.0 ± 9.4 in proximal, midportion, and distal Achilles tendon, respectively; P < 0.01). Eccentric heel-raise exercise led to ∼2 times increase of Achilles tendon blood flow in healthy participants. Consistent with its vascular origin, the estimated f p demonstrated a high dependency to IVIM protocol parameters, while the T 1 /T 2 -corrected absolute intratendinous microvascular blood volume fraction (V b ) did not vary. Achilles tendon ste-RS-EPI IVIM noninvasively

  12. Tendon entheses of the human masticatory muscles.

    PubMed

    Hems, T; Tillmann, B

    2000-09-01

    Tendons attach to the limb skeleton via chondral-apophysary or periosteal-diaphysary entheses. It was the aim of the present study to investigate the tendon entheses of the temporal, the masseter, as well as the medial and lateral pterygoid muscles, considering the biomechanics and the mode of osteogenesis at the attachment sites. The origin and insertion zones of the four masticatory muscles were studied histologically and by polarization light microscopy in six halves of human heads. Contrary to the limb skeleton no causal relationship between the histological structure of the tendon entheses and the osteogenic mode of the bone areas involved was observed in the masticatory muscles that were studied. Based on the histological findings, a purely structural classification of the tendon attachments irrespective of the osteogenesis is therefore proposed that is applicable to the entire skeleton. It is possible to distinguish between tendon entheses inserting into periosteum, into bone or into fibrocartilage. Tendon attachments with periosteal insertion are found at the temporal plane, the retromolar triangle, zygomatic arch, lateral pterygoid plate, in the caudal zone of the pterygoid fovea of the neck of mandible as well as major portions of the ramus and angle of the mandible. The attachment zones in which collagen fibrils of tendons insert into the bone via the periosteum correspond in their structure to plane periosteal-diaphysary insertions into the diaphyses of long bones. Attachment zones to the bone are present at the inferior temporal line, the base of the coronoid process, the caudal surface of the zygomatic arch, the cranial zones of the pterygoid fovea of the neck of the mandible as well as at circumscribed areas of the ramus and angle of the mandible. In these zones the collagen fibers of the tendon insert immediately into the bone without any mediation of other tissues. The entheses resemble those of circumscribed periosteal-diaphysary attachments to

  13. Closing the gap on Achilles tendon rupture: A cadaveric study quantifying the tendon apposition achieved with commonly used immobilisation practices.

    PubMed

    Collins, Ruaraidh; Sudlow, Alexis; Loizou, Constantinos; Loveday, David T; Smith, George

    2018-04-01

    The relative benefits of surgical and conservative treatment of Achilles tendon rupture are widely debated. With modern conservative management protocols, the re-rupture risk appears to fall to one similar to surgical repair with negligible loss of function. Conservative management typically employs a period of time in an equinus cast with sequential ankle dorsiflexion in a functional orthosis. The optimal duration of immobilisation and rate of dorsiflexion is unknown. We aimed to quantify the change in Achilles tendon approximation achieved in common immobilisation techniques to assist the design of rehabilitation protocols. Twelve fresh-frozen cadaveric specimens had 2.5cm of Achilles tendon excised. The gap between the tendon ends were measured via windowed full equinus casts and compared with functional boots with successively removed heel wedges. The greatest tendon apposition was achieved with the equinus cast. Each wedge removed decreased the reapproximation by approximately 5mm. This paper supports the early use of maximal equinus casting in early management of acute Achilles tendon ruptures. Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  14. Tendon allograft sterilized by peracetic acid/ethanol combined with gamma irradiation.

    PubMed

    Zhou, Mo; Zhang, Naili; Liu, Xiaoming; Li, Youchen; Zhang, Yumin; Wang, Xusheng; Li, Baoming; Li, Baoxing

    2014-07-01

    Research and clinical applications have demonstrated that the effects of tendon allografts are comparable to those of autografts when reconstructing injured tendons or ligaments, but allograft safety remains problematic. Sterilisation could eliminate or decrease the possibility of disease transmission, but current methods seldom achieve satisfactory sterilisation without affecting the mechanical properties of the tendon. Peracetic acid-ethanol in combination with low-dose gamma irradiation (PE-R) would inactivate potential deleterious microorganisms without affecting mechanical and biocompatible properties of tendon allograft. Controlled laboratory design. HIV, PPV, PRV and BVDV inactivation was evaluated. After verifying viral inactivation, the treated tendon allografts were characterised by optical microscopy, scanning electron microscopy and tensile testing, and the cytocompatibility was assessed with an MTT assay and by subcutaneous implantation. Effective and efficient inactivation of HIV, PPV, PRV and BVDV was observed. Histological structure and ultrastructure were unchanged in the treated tendon allograft, which also exhibited comparable biomechanical properties and good biocompatibility. The preliminary results confirmed our hypothesis and demonstrated that the PE-R tendon allograft has significant potential as an alternative to ligament/tendon reconstruction. Tendon allografts have been extensively used in ligament reconstruction and tendon repair. However, current sterilisation methods have various shortcomings, so PE-R has been proposed. This study suggests that PE-R tendon allograft has great potential as an alternative for ligament/tendon reconstruction. Sterilisation has been a great concern for tendon allografts. However, most sterilisation methods cannot inactivate viruses and bacteria without impairing the mechanical properties of the tendon allograft. Peracetic acid/ethanol with gamma irradiation can effectively inactivate viruses and bacteria

  15. Conservative management of partial extensor tendon lacerations greater than half the width of the tendon in manual workers.

    PubMed

    Al-Qattan, Mohammad M

    2015-04-01

    Conservative management (without suturing or splints) of partial extensor tendon lacerations greater than half the width of the tendon has not been previously investigated. In this prospective study, a total of 45 injured tendons (with lacerations involving 55%-90% of the width of the tendon) in 39 patients were treated conservatively. Injury zones I, III, and V of the fingers; and zones I and III of the thumb were excluded. Immediate non-resistive active mobilization was initiated and continued for 4 weeks, followed by resistive exercises. Patients were allowed to go back to work after 6 weeks. There were no cases of ruptures, triggering, infection, or complex regional pain syndrome. At final follow-up (8-9 months after injury), all patients obtained full range of motion with no extension lags. All patients were able to go back to normal duties. We conclude that early active motion without the use of splints or sutures in major extensor tendon lacerations in zones II, IV, VI-VIII of the fingers; and zones II, IV, and V of the thumb is safe.

  16. Is there still a place for Achilles tendon lengthening?

    PubMed

    Tagoe, Mark T; Reeves, Neil D; Bowling, Frank L

    2016-01-01

    Patients with diabetes and ankle equinus are at particularly high risk for forefoot ulceration because of the development of high forefoot pressures. Stiffness in the triceps surae muscles and tendons are thought to be largely responsible for equinus in patients with diabetes and underpins the surgical rationale for Achilles tendon lengthening (ATL) procedures to alleviate this deformity and reduce ulcer risk. The established/traditional surgical approach is the triple hemisection along the length of the Achilles tendon. Although the percutaneous approach has been successful in achieving increases in ankle dorsiflexion >30°, the tendon rupture risk has led to some surgeons looking at alternative approaches. The gastrocnemius aponeurosis may be considered as an alternative because of the Achilles tendon's poor blood supply. ATL procedures are a balance between achieving adequate tendon lengthening and minimizing tendon rupture risk during or after surgery. After ATL surgery, the first 7 days should involve reduced loading and protected range of motion to avoid rupture, after which gradual reintroduction to loading should be encouraged to increase tendon strength. In summary, there is a moderate level of evidence to support surgical intervention for ankle joint equinus in patients with diabetes and forefoot ulceration that is non-responsive to other conservative treatments. Areas of caution for ATL procedures include the risk for overcorrection, tendon rupture and the tendon's poor blood supply. Further prospective randomized control trials are required to confirm the benefits of ATL procedures over conservative care and the most optimal anatomical sites for surgical intervention. Copyright © 2016 John Wiley & Sons, Ltd.

  17. Achilles tendon reflex measuring system

    NASA Astrophysics Data System (ADS)

    Szebeszczyk, Janina; Straszecka, Joanna

    1995-06-01

    The examination of Achilles tendon reflex is widely used as a simple, noninvasive clinical test in diagnosis and pharmacological therapy monitoring in such diseases as: hypothyroidism, hyperthyroidism, diabetic neuropathy, the lower limbs obstructive angiopathies and intermittent claudication. Presented Achilles tendon reflect measuring system is based on the piezoresistive sensor connected with the cylinder-piston system. To determinate the moment of Achilles tendon stimulation a detecting circuit was used. The outputs of the measuring system are connected to the PC-based data acquisition board. Experimental results showed that the measurement accuracy and repeatability is good enough for diagnostics and therapy monitoring purposes. A user friendly, easy-to-operate measurement system fulfills all the requirements related to recording, presentation and storing of the patients' reflexograms.

  18. Radial and ulnar bursae of the wrist: cadaveric investigation of regional anatomy with ultrasonographic-guided tenography and MR imaging.

    PubMed

    Aguiar, Rodrigo O C; Gasparetto, Emerson L; Escuissato, Dante L; Marchiori, Edson; Trudell, Debbie J; Haghighi, Parviz; Resnick, Donald

    2006-11-01

    To demonstrate the anatomy of the radial and ulnar bursae of the wrist using MR and US images. Ultrasonographic-guided tenography of the tendon sheath of flexor pollicis longus (FPL) and the common tendon sheath of the flexor digitorum of the fifth digit (FD5) of ten cadaveric hands was performed, followed by magnetic resonance imaging and gross anatomic correlation. Patterns of communication were observed between these tendon sheaths and the radial and ulnar bursae of the wrist. The tendon sheath of the FPL communicated with the radial bursa in 100% (10/10) of cases, and the tendon sheath of the FD5 communicated with the ulnar bursa in 80% (8/10). Communication of the radial and ulnar bursae was evident in 100% (10/10), and presented an "hourglass" configuration in the longitudinal plane. The ulnar and radial bursae often communicate. The radial bursa communicates with the FPL tendon sheath, and the ulnar bursa may communicate with the FD5 tendon sheath.

  19. Tendon basic science: Development, repair, regeneration, and healing.

    PubMed

    Andarawis-Puri, Nelly; Flatow, Evan L; Soslowsky, Louis J

    2015-06-01

    Tendinopathy and tendon rupture are common and disabling musculoskeletal conditions. Despite the prevalence of these injuries, a limited number of investigators are conducting fundamental, basic science studies focused on understanding processes governing tendinopathies and tendon healing. Development of effective therapeutics is hindered by the lack of fundamental guiding data on the biology of tendon development, signal transduction, mechanotransduction, and basic mechanisms underlying tendon pathogenesis and healing. To propel much needed progress, the New Frontiers in Tendon Research Conference, co-sponsored by NIAMS/NIH, the Orthopaedic Research Society, and the Icahn School of Medicine at Mount Sinai, was held to promote exchange of ideas between tendon researchers and basic science experts from outside the tendon field. Discussed research areas that are underdeveloped and represent major hurdles to the progress of the field will be presented in this review. To address some of these outstanding questions, conference discussions and breakout sessions focused on six topic areas (Cell Biology and Mechanics, Functional Extracellular Matrix, Development, Mechano-biology, Scarless Healing, and Mechanisms of Injury and Repair), which are reviewed in this special issue and briefly presented in this review. Review articles in this special issue summarize the progress in the field and identify essential new research directions. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  20. Regional strain variations in the human patellar tendon.

    PubMed

    Pearson, Stephen J; Ritchings, Tim; Mohamed, Azlan S A

    2014-07-01

    Characteristics of localized tendon strain in vivo are largely unknown. The present study examines local tendon strain between the deep, middle, and surface structures at the proximal and distal aspects of the patellar tendon during ramped isometric contractions. Male subjects (age 28.0 ± 6.3 yr) were examined for patellar tendon excursion (anterior, midsection, and posterior) during ramped isometric voluntary contractions using real-time B-mode ultrasonography and dynamometry. Regional tendon excursion measurements were compared using an automated pixel tracking method. Strain was determined from the tendon delta length normalized to initial/resting segment length. Strain increased from 10% to 100% of force for all regions. Significantly greater mean strain was seen for the anterior proximal region compared to the posterior and mid layer of the tendon (7.5% ± 1.1% vs 3.7% ± 0.5% vs 5.5% ± 1.0%; P < 0.05). Similarly, the distal posterior region showed greater mean strain compared to the mid and anterior regions (7.9% ± 0.6% vs 5.0% ± 0.6% vs 5.4% ± 0.6%; P < 0.05). Relative changes in strain differences from 50% to 100% of force for the proximal region were greatest for the anterior to midline regions (4.6% ± 0.6% and 5.6% ± 0.6%, respectively) and those for the distal region were also greatest for the anterior to midline regions (4.4% ± 0.2% and 5.3% ± 0.2%, respectively). The largest mean strain for the proximal region was at the anterior layer (7.5% ± 1.1%) and that for the distal tendon region was at the posterior layer (7.9% ± 0.9%). This study shows significant regional differences in strain during ramped isometric contractions for the patellar tendon. Lower proximal strains in the posterior tendon compared to the anterior region may be associated with the suggestion of "stress shielding" as an etiological factor in insertional tendinopathy.

  1. Torque Control of Underactuated Tendon-driven Robotic Fingers

    NASA Technical Reports Server (NTRS)

    Ihrke, Chris A. (Inventor); Wampler, Charles W. (Inventor); Abdallah, Muhammad E. (Inventor); Reiland, Matthew J. (Inventor); Diftler, Myron A. (Inventor); Bridgwater, Lyndon (Inventor); Platt, Robert (Inventor)

    2013-01-01

    A robotic system includes a robot having a total number of degrees of freedom (DOF) equal to at least n, an underactuated tendon-driven finger driven by n tendons and n DOF, the finger having at least two joints, being characterized by an asymmetrical joint radius in one embodiment. A controller is in communication with the robot, and controls actuation of the tendon-driven finger using force control. Operating the finger with force control on the tendons, rather than position control, eliminates the unconstrained slack-space that would have otherwise existed. The controller may utilize the asymmetrical joint radii to independently command joint torques. A method of controlling the finger includes commanding either independent or parameterized joint torques to the controller to actuate the fingers via force control on the tendons.

  2. Tendon biomechanics and mechanobiology--a minireview of basic concepts and recent advancements.

    PubMed

    Wang, James H-C; Guo, Qianping; Li, Bin

    2012-01-01

    Due to their unique hierarchical structure and composition, tendons possess characteristic biomechanical properties, including high mechanical strength and viscoelasticity, which enable them to carry and transmit mechanical loads (muscular forces) effectively. Tendons are also mechanoresponsive by adaptively changing their structure and function in response to altered mechanical loading conditions. In general, mechanical loading at physiological levels is beneficial to tendons, but excessive loading or disuse of tendons is detrimental. This mechanoadaptability is due to the cells present in tendons. Tendon fibroblasts (tenocytes) are the dominant tendon cells responsible for tendon homeostasis and repair. Tendon stem cells (TSCs), which were recently discovered, also play a vital role in tendon maintenance and repair by virtue of their ability to self-renew and differentiate into tenocytes. TSCs may also be responsible for chronic tendon injury, or tendinopathy, by undergoing aberrant differentiation into nontenocytes in response to excessive mechanical loading. Thus, it is necessary to devise optimal rehabilitation protocols to enhance tendon healing while reducing scar tissue formation and tendon adhesions. Moreover, along with scaffolds that can mimic tendon matrix environments and platelet-rich plasma, which serves as a source of growth factors, TSCs may be the optimal cell type for enhancing repair of injured tendons. Copyright © 2012 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  3. Tendon Reattachment to Bone in an Ovine Tendon Defect Model of Retraction Using Allogenic and Xenogenic Demineralised Bone Matrix Incorporated with Mesenchymal Stem Cells.

    PubMed

    Thangarajah, Tanujan; Shahbazi, Shirin; Pendegrass, Catherine J; Lambert, Simon; Alexander, Susan; Blunn, Gordon W

    2016-01-01

    Tendon-bone healing following rotator cuff repairs is mainly impaired by poor tissue quality. Demineralised bone matrix promotes healing of the tendon-bone interface but its role in the treatment of tendon tears with retraction has not been investigated. We hypothesized that cortical demineralised bone matrix used with minimally manipulated mesenchymal stem cells will result in improved function and restoration of the tendon-bone interface with no difference between xenogenic and allogenic scaffolds. In an ovine model, the patellar tendon was detached from the tibial tuberosity and a complete distal tendon transverse defect measuring 1 cm was created. Suture anchors were used to reattach the tendon and xenogenic demineralised bone matrix + minimally manipulated mesenchymal stem cells (n = 5), or allogenic demineralised bone matrix + minimally manipulated mesenchymal stem cells (n = 5) were used to bridge the defect. Graft incorporation into the tendon and its effect on regeneration of the enthesis was assessed using histomorphometry. Force plate analysis was used to assess functional recovery. Compared to the xenograft, the allograft was associated with significantly higher functional weight bearing at 6 (P = 0.047), 9 (P = 0.028), and 12 weeks (P = 0.009). In the allogenic group this was accompanied by greater remodeling of the demineralised bone matrix into tendon-like tissue in the region of the defect (p = 0.015), and a more direct type of enthesis characterized by significantly more fibrocartilage (p = 0.039). No failures of tendon-bone healing were noted in either group. Demineralised bone matrix used with minimally manipulated mesenchymal stem cells promotes healing of the tendon-bone interface in an ovine model of acute tendon retraction, with superior mechanical and histological results associated with use of an allograft.

  4. Extensor Tendon Injuries and Repairs in the Hand

    PubMed Central

    Kontor, J. A.

    1982-01-01

    Due to their superficial course, the extensor tendons are frequently lacerated over the dorsum of the hand and fingers. Excellent functional results are obtained in repairs of simple tendon lacerations. ‘Open’ mallet lacerations over the distal IP joint or involving the central extensor slip over the proximal IP joint require more precise suturing methods. More proximal extensor tendon divisions near the wrist involve dissection of the retracted finger extensors or long thumb extensor in the distal forearm and more formal tendon repairs, including a possible tendon transfer to the thumb. ‘Closed injuries’, with varying degrees of extensor tendon disruption, occur at three main sites. The mallet injury at the DIP joint and the boutonnière deformity over the PIP joint are sometimes recognized late, but respond to conservative splinting for a minimum of four weeks with guarded motion avoiding secondary stiffening of the remaining small joints of the hand. Surgery of closed injuries most frequently involves the intra-articular traction fracture type of mallet deformities in which the DIP joint has taken the brunt of the injury. PMID:21286174

  5. Tendon Reconstruction with Tissue Engineering Approach--A Review.

    PubMed

    Verdiyeva, Gunay; Koshy, Kiron; Glibbery, Natalia; Mann, Haroon; Seifalian, Alexander M

    2015-09-01

    Tendon injuries are a common and rising occurrence, associated with significant impairment to quality of life and financial burden to the healthcare system. Clinically, they represent an unresolved problem, due to poor natural tendon healing and the inability of current treatment strategies to restore the tendon to its native state. Tissue engineering offers a promising alternative, with the incorporation of scaffolds, cells and growth factors to support the complete regeneration of the tendon. The materials used in tendon engineering to date have provided significant advances in structural integrity and biological compatibility and in many cases the results obtained are superior to those observed in natural healing. However, grafts fail to reproduce the qualities of the pre-injured tendon and each has weaknesses subject to its constituent parts. Furthermore, many materials and cell types are being investigated concurrently, with seemingly little association or comparison between research results. In this review the properties of the most-investigated and effective components have been appraised in light of the surrounding literature, with research from early in-vitro experiments to clinical trials being discussed. Extensive comparisons have been made between scaffolds, cell types and growth factors used, listing strengths and weaknesses to provide a stable platform for future research. Promising future endeavours are also described in the field of nanocomposite material science, stem cell sources and growth factors, which may bypass weaknesses found in individual elements. The future of tendon engineering looks bright, with growing understanding in material technology, cell and growth factor application and encouraging recent advances bringing us ever closer to regenerating the native tendon.

  6. Modelling approaches for evaluating multiscale tendon mechanics

    PubMed Central

    Fang, Fei; Lake, Spencer P.

    2016-01-01

    Tendon exhibits anisotropic, inhomogeneous and viscoelastic mechanical properties that are determined by its complicated hierarchical structure and varying amounts/organization of different tissue constituents. Although extensive research has been conducted to use modelling approaches to interpret tendon structure–function relationships in combination with experimental data, many issues remain unclear (i.e. the role of minor components such as decorin, aggrecan and elastin), and the integration of mechanical analysis across different length scales has not been well applied to explore stress or strain transfer from macro- to microscale. This review outlines mathematical and computational models that have been used to understand tendon mechanics at different scales of the hierarchical organization. Model representations at the molecular, fibril and tissue levels are discussed, including formulations that follow phenomenological and microstructural approaches (which include evaluations of crimp, helical structure and the interaction between collagen fibrils and proteoglycans). Multiscale modelling approaches incorporating tendon features are suggested to be an advantageous methodology to understand further the physiological mechanical response of tendon and corresponding adaptation of properties owing to unique in vivo loading environments. PMID:26855747

  7. Tendon material properties vary and are interdependent among turkey hindlimb muscles.

    PubMed

    Matson, Andrew; Konow, Nicolai; Miller, Samuel; Konow, Pernille P; Roberts, Thomas J

    2012-10-15

    The material properties of a tendon affect its ability to store and return elastic energy, resist damage, provide mechanical feedback and amplify or attenuate muscle power. While the structural properties of a tendon are known to respond to a variety of stimuli, the extent to which material properties vary among individual muscles remains unclear. We studied the tendons of six different muscles in the hindlimb of Eastern wild turkeys to determine whether there was variation in elastic modulus, ultimate tensile strength and resilience. A hydraulic testing machine was used to measure tendon force during quasi-static lengthening, and a stress-strain curve was constructed. There was substantial variation in tendon material properties among different muscles. Average elastic modulus differed significantly between some tendons, and values for the six different tendons varied nearly twofold, from 829±140 to 1479±106 MPa. Tendons were stretched to failure, and the stress at failure, or ultimate tensile stress, was taken as a lower-limit estimate of tendon strength. Breaking tests for four of the tendons revealed significant variation in ultimate tensile stress, ranging from 66.83±14.34 to 112.37±9.39 MPa. Resilience, or the fraction of energy returned in cyclic length changes was generally high, and one of the four tendons tested was significantly different in resilience from the other tendons (range: 90.65±0.83 to 94.02±0.71%). An analysis of correlation between material properties revealed a positive relationship between ultimate tensile strength and elastic modulus (r(2)=0.79). Specifically, stiffer tendons were stronger, and we suggest that this correlation results from a constrained value of breaking strain, which did not vary significantly among tendons. This finding suggests an interdependence of material properties that may have a structural basis and may explain some adaptive responses observed in studies of tendon plasticity.

  8. Surface Modification Counteracts Adverse Effects Associated with Immobilization after Flexor Tendon Repair

    PubMed Central

    Zhao, Chunfeng; Sun, Yu-Long; Jay, Gregory D.; Moran, Steven L.; An, Kai-Nan; Amadio, Peter C.

    2012-01-01

    SUMMARY Although post-rehabilitation is routinely performed following flexor tendon repair, in some clinical scenarios post-rehabilitation must be delayed. We investigated modification of the tendon surface using carbodiimide derivatized hyaluronic acid and lubricin (cd-HA-Lub) to maintain gliding function following flexor tendon repair with postoperative immobilization in a in vivo canine model. Flexor digitorum profundus tendons from the 2nd and 5th digits of one forepaw of six dogs were transected and repaired. One tendon in each paw was treated with cd-HA-Lub; the other repaired tendon was not treated. Following tendon repair, a forearm cast was applied to fully immobilize the operated forelimb for 10 days, after which the animals were euthanized. Digit normalized work of flexion (nWOF) and tendon gliding resistance were assessed. The nWOF of the FDP tendons treated with cd-HA-Lub was significantly lower than the nWOF of the untreated tendons (p < 0.01). The gliding resistance of cd-HA-Lub treated tendons was also significantly lower than that of the untreated tendons (p < 0.05). Surface treatment with cd-HA-Lub following flexor tendon repair provides an opportunity to improve outcomes for patients in whom the post-operative therapy must be delayed after flexor tendon repair. PMID:22714687

  9. Light microscopic histology of supraspinatus tendon ruptures.

    PubMed

    Longo, Umile Giuseppe; Franceschi, Francesco; Ruzzini, Laura; Rabitti, Carla; Morini, Sergio; Maffulli, Nicola; Forriol, Francisco; Denaro, Vincenzo

    2007-11-01

    We analysed the morphological features of the human surgical specimens of supraspinatus tendon from patients with rotator cuff tears. Tendon samples were harvested from 31 subjects (21 men and 10 women; mean age 51 years, range 38-64) who underwent arthroscopic repair of a rotator cuff tear, and from five male patients who died of cardiovascular events (mean age, 69.6 years). Histological examination was performed using Haematoxylin and Eosin, Masson's Trichrome and Van Gieson's connective tissue stain. The specimens were examined twice by the same examiner under white light and polarized light microscopy. Particular effort was made to assess any evidence of the changes associated with tendinopathy. Within each specific category of tendon abnormalities, the chi-square test showed significant differences between the control and ruptured tendons (P < 0.05). Using the kappa statistics, the agreement between the two readings ranged from 0.57 to 0.84. We found thinning and disorientation of collagen fibres and chondroid metaplasia to be more pronounced on the articular side of the specimens from patients with rotator cuff tear (P < 0.05). The present study provides a description of the histological architecture of human surgical specimens of normal supraspinatus tendon from patients with rotator cuff tears and demonstrates more frequent tendon changes on the articular side of the rotator cuff.

  10. Flexor Tendon Repair With Looped Suture: 1 Versus 2 Knots.

    PubMed

    Gil, Joseph A; Skjong, Christian; Katarincic, Julia A; Got, Christopher

    2016-03-01

    To assess the strength of flexor tendon repair with looped suture. We hypothesized that, after passing the intact looped suture in the desired repair configuration, splitting the loop and tying 2 independent knots would increase the strength of flexor tendon repair. Thirty-two flexor tendons were harvested and were sharply transected in zone II. The tendons were repaired with a 4-strand core suture repair using 3-0 looped nonabsorbable nylon suture. The harvested tendons were randomly assigned and repaired with either a 1- or a 2-knot construct. The repaired flexor tendons were fixed in a servohydraulic material testing system and were loaded to failure either with uniaxial tension or cyclically. The average force at failure was 43 N for the 1-knot repair and 28 N for the 2-knot repair. The mode of failure of 15 of the flexor tendon repairs that were cyclically loaded to failure was suture pull-out. The average number of cycles and force in cyclic testing that caused failure of flexor tendon repairs was 134 cycles and 31 N for tendons repaired with looped 3-0 suture tied with 1 knot and 94 cycles and 33 N for tendons repaired with looped 3-0 suture tied with 2 knots. Our hypothesis was disproved by the results of this study. This study suggests that, when using looped suture, tying 2 independent knots instead of tying a single knot does not increase the strength of the flexor tendon repair. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  11. Muscle-Tendon-Enthesis Unit.

    PubMed

    Tadros, Anthony S; Huang, Brady K; Pathria, Mini N

    2018-07-01

    Injuries to the muscle-tendon-enthesis unit are common and a significant source of pain and loss of function. This article focuses on the important anatomical and biomechanical considerations for each component of the muscle-tendon-enthesis unit. We review normal and pathologic conditions affecting this unit, illustrating the imaging appearance of common disorders on magnetic resonance imaging and ultrasound. Knowledge of the anatomy and biomechanics of these structures is crucial for the radiologist to make accurate diagnoses and provide clinically relevant assessments. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  12. Platelet-rich plasma in tendon-related disorders: results and indications.

    PubMed

    Filardo, Giuseppe; Di Matteo, Berardo; Kon, Elizaveta; Merli, Giulia; Marcacci, Maurilio

    2016-09-24

    Platelet-rich plasma (PRP) is currently the most exploited strategy in the clinical practice to provide a regenerative stimulus for tendon healing. The aim of the present study was to systematically review the available evidence on the treatment of the main tendon disorders where PRP is currently applied. A systematic review of the literature was performed on the use of PRP as a treatment for tendinopathies focusing on the following sites: Achilles tendon, patellar tendon, rotator cuff tendons, and lateral elbow tendons. The following inclusion criteria for relevant articles were used: clinical trials written in English language up to 21 June 2016 on the use of PRP in the conservative or surgical treatment of the aforementioned tendinopathies. The research identified the following clinical trials dealing with the application of PRP in the selected tendons: 19 papers on patellar tendon (6 being RCTs: 4 dealing with PRP conservative application and 2 surgical), 24 papers on Achilles tendon (4 RCTs: 3 conservative and 1 surgical), 29 on lateral elbow tendons (17 RCTs, all conservative), and 32 on rotator cuff (22 RCTs: 18 surgical and 3 conservative). Patellar tendons seem to benefit from PRP injections, whereas in the Achilles tendon, PRP application is not indicated neither as a conservative approach nor as a surgical augmentation. Lateral elbow tendinopathy showed an improvement in most of the high-level studies, but the lack of proven superiority with respect to the more simple whole-blood injections still questions its use in the clinical practice. With regard to rotator cuff pathology, the vast majority of surgical RCTs documented a lack of beneficial effects, whereas there is still inconclusive evidence concerning its conservative application in rotator cuff disorders. Systematic review of level I-IV trials, Level IV.

  13. Sonographic differentiation of digital tendon rupture from adhesive scarring after primary surgical repair.

    PubMed

    Budovec, Joseph J; Sudakoff, Gary S; Dzwierzynski, William W; Matloub, Hani S; Sanger, James R

    2006-04-01

    After the surgical repair of finger tendons finger range of motion may be limited by tendon rupture or adhesive scarring. Differentiating tendon rupture from adhesive scarring may be difficult clinically. Digital tendon sonography allows the evaluation of tendon integrity in a dynamic setting. Our objective was to determine if sonography could differentiate tendon rupture from adhesive scarring in patients who have had primary tendon repair. A retrospective review was performed of the radiographic, clinical, and surgical records of patients referred for finger sonography over a 2-year period. Twenty-eight digits in 21 patients were evaluated for finger tendon disruption after primary surgical repair. The diagnosis of complete tendon rupture was made when 1 or more of the following was identified: a gap separating the proximal and distal tendon margins, visualization of only the proximal tendon margin, or visualization of only the distal tendon margin. Adhesive scarring was diagnosed if the tendon appeared intact with abnormal peritendinous soft tissue abutting or partially encasing the tendon, with synovial sheath thickening, or with restricted tendon motion during dynamic evaluation. Sonography correctly identified tendon rupture or adhesive scarring in 27 of 28 digits with 1 false-positive case (sensitivity, 100%; specificity, 93%; positive-predictive value, 93%; negative-predictive value, 100%; accuracy, 96%). Sonography is an accurate modality for differentiating tendon rupture from adhesive scarring in patients with prior surgical tendon repair. Diagnostic, Level I.

  14. The role of the non-collagenous matrix in tendon function.

    PubMed

    Thorpe, Chavaunne T; Birch, Helen L; Clegg, Peter D; Screen, Hazel R C

    2013-08-01

    Tendon consists of highly ordered type I collagen molecules that are grouped together to form subunits of increasing diameter. At each hierarchical level, the type I collagen is interspersed with a predominantly non-collagenous matrix (NCM) (Connect. Tissue Res., 6, 1978, 11). Whilst many studies have investigated the structure, organization and function of the collagenous matrix within tendon, relatively few have studied the non-collagenous components. However, there is a growing body of research suggesting the NCM plays an important role within tendon; adaptations to this matrix may confer the specific properties required by tendons with different functions. Furthermore, age-related alterations to non-collagenous proteins have been identified, which may affect tendon resistance to injury. This review focuses on the NCM within the tensional region of developing and mature tendon, discussing the current knowledge and identifying areas that require further study to fully understand structure-function relationships within tendon. This information will aid in the development of appropriate techniques for tendon injury prevention and treatment. © 2013 The Authors. International Journal of Experimental Pathology © 2013 International Journal of Experimental Pathology.

  15. Postinjury biomechanics of Achilles tendon vary by sex and hormone status

    PubMed Central

    Fryhofer, George W.; Freedman, Benjamin R.; Hillin, Cody D.; Salka, Nabeel S.; Pardes, Adam M.; Weiss, Stephanie N.; Farber, Daniel C.

    2016-01-01

    Achilles tendon ruptures are common injuries. Sex differences are present in mechanical properties of uninjured Achilles tendon, but it remains unknown if these differences extend to tendon healing. We hypothesized that ovariectomized females (OVX) and males would exhibit inferior postinjury tendon properties compared with females. Male, female, and OVX Sprague-Dawley rats (n = 32/group) underwent acclimation and treadmill training before blunt transection of the Achilles tendon midsubstance. Injured hindlimbs were immobilized for 1 wk, followed by gradual return to activity and assessment of active and passive hindlimb function. Animals were euthanized at 3 or 6 wk postinjury to assess tendon structure, mechanics, and composition. Passive ankle stiffness and range of motion were superior in females at 3 wk; however, by 6 wk, passive and active function were similar in males and females but remained inferior in OVX. At 6 wk, female tendons had greater normalized secant modulus, viscoelastic behavior, and laxity compared with males. Normalized secant modulus, cross-sectional area and tendon glycosaminoglycan composition were inferior in OVX compared with females at 6 wk. Total fatigue cycles until tendon failure were similar among groups. Postinjury muscle fiber size was better preserved in females compared with males, and females had greater collagen III at the tendon injury site compared with males at 6 wk. Despite male and female Achilles tendons withstanding similar durations of fatigue loading, early passive hindlimb function and tendon mechanical properties, including secant modulus, suggest superior healing in females. Ovarian hormone loss was associated with inferior Achilles tendon healing. PMID:27633741

  16. Supraspinatus tendon micromorphology in individuals with subacromial pain syndrome.

    PubMed

    Pozzi, Federico; Seitz, Amee L; Plummer, Hillary A; Chow, Kira; Bashford, Gregory R; Michener, Lori A

    Cross-sectional cohort. Tendon collagen organization can be estimated by peak spatial frequency radius (PSFR) on ultrasound images. Characterizing PSFR can define the contribution of collagen disruption to shoulder symptoms. The purpose of this was to characterize the (1) supraspinatus tendon PSFR in participants with subacromial pain syndrome (SPS) and healthy controls; (2) PSFR between participants grouped on a tendon visual quality score; and (3) relationship between PSFR with patient-reported pain, function, and shoulder strength. Participants with SPS (n = 20) and age, sex, and arm-dominance-matched healthy controls (n = 20) completed strength testing in scaption and external rotation, and patient-reported pain, and functional outcomes. Supraspinatus tendon ultrasound images were acquired, and PSFR was calculated for a region of interest 15 mm medial to the supraspinatus footprint. PSFR was compared between groups using an independent t-test and an analysis of variance to compare between 3 groups for visually qualitatively rated tendon abnormalities. Relationships between PSFR with pain, function, and strength were assessed using Pearson correlation coefficient. Supraspinatus tendon PSFR was not different between groups (P = .190) or tendon qualitative ratings (P = .556). No relationship was found between PSFR and pain, functional loss, and strength (P > .05). Collagen disruption (PSFR) measured via ultrasound images of the supraspinatus tendon was not different between participants with SPS or in those with visually rated tendon defects. PSFR is not related to shoulder pain, function, and strength, suggesting that supraspinatus tendon collagen disorganization may not be a contributing factor to shoulder SPS. However, collagen disruption may not be isolated to a single region of interest. 3b: case-control study. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  17. Prevalence and Role of a Low-Lying Peroneus Brevis Muscle Belly in Patients With Peroneal Tendon Pathologic Features: A Potential Source of Tendon Subluxation.

    PubMed

    Mirmiran, Roya; Squire, Chad; Wassell, Daniel

    2015-01-01

    A peroneus brevis low-lying muscle belly (LLMB) is a rare anomaly. A few published studies have supported the presence of this anomaly as an etiology for a peroneal tendon tear. However, the association between a peroneus brevis LLMB and tendon subluxation has not been well explored. In the present retrospective study, the magnetic resonance imaging (MRI) and intraoperative findings of 50 consecutive patients undergoing primary peroneal tendon surgery during a 5-year period were assessed. The sensitivity and specificity of MRI compared with the intraoperative findings for identifying peroneal tendon disease were investigated. The presence of associated peroneal tendon pathologic features in patients with and without a peroneus brevis LLMB was also compared. The sensitivity of MRI was high for identifying peroneal tenosynovitis (81.58%) and tear (85.71%). Although the sensitivity of MRI for detecting a peroneus brevis LLMB (3.23%) and tendon subluxation (10.00%) was low, MRI had high specificity at 94.74% and 100%, respectively. Intraoperatively, a peroneus brevis LLMB was seen in 62.00% of the patients with chronic lateral ankle pain and was associated with 64.52% of the patients with tenosynovitis, 29.03% of those with tendon subluxation, and 80.65% of those with a peroneus brevis tendon tear. Although the presence of a peroneus brevis LLMB did not show any statistically significant association with peroneus brevis tendon subluxation, of the 10 patients with intraoperatively observed tendon subluxation, 9 had a concomitant peroneus brevis LLMB. More studies with larger patient populations are needed to better investigate the role of a peroneus brevis LLMB as a mass-occupying lesion resulting in peroneal tendon subluxation. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  18. FROM ACUTE ACHILLES TENDON RUPTURE TO RETURN TO PLAY - A CASE REPORT EVALUATING RECOVERY OF TENDON STRUCTURE, MECHANICAL PROPERTIES, CLINICAL AND FUNCTIONAL OUTCOMES.

    PubMed

    Zellers, Jennifer A; Cortes, Daniel H; Silbernagel, Karin Grävare

    2016-12-01

    Achilles tendon rupture results in significant functional deficits regardless of treatment strategy (surgical versus non-surgical intervention). Recovery post-rupture is highly variable, making comprehensive patient assessment critical. Assessment tools may change along the course of recovery as the patient progresses - for instance, moving from a seated heel-rise to standing heel-rise to jump testing. However, tools that serve as biomarkers for early recovery may be particularly useful in informing clinical decision-making. The purpose of this case report was to describe the progress of a young, athletic individual following Achilles tendon rupture managed non-surgically, using patient reported and functional performance outcome measures and comprehensively evaluating Achilles tendon structure and function incorporating a novel imaging technique (cSWE). The subject is a 26 year-old, female basketball coach who sustained an Achilles tendon rupture and was managed non-surgically. The subject was able to steadily progress using a gradual tendon loading treatment approach well-supported by the literature. Multiple evaluative techniques including the addition of diagnostic ultrasound imaging and continuous shear wave elastography (cSWE) to standard clinical tests and measures were used to assess patient-reported symptoms, tendon structure, and tendon functional performance. Five assessments were performed over the course of 2-14 months post-rupture. By the 14-month follow-up, the subject had achieved full self-reported function. Tendon structural and mechanical properties showed similar shear modulus by 14 months, however, viscosity continued to be lower and tendon length longer on the ruptured side. Functional performance, evidenced by the heel-rise test and jump tests, also showed a positive trajectory, however, deficits of 12-28% remained between ruptured and non-ruptured sides at 14 months. This case report outlines comprehensive outcomes assessment in an athletic

  19. Cell-laden composite suture threads for repairing damaged tendons.

    PubMed

    Costa-Almeida, Raquel; Domingues, Rui M A; Fallahi, Afsoon; Avci, Huseyin; Yazdi, Iman K; Akbari, Mohsen; Reis, Rui L; Tamayol, Ali; Gomes, Manuela E; Khademhosseini, Ali

    2018-04-01

    Tendons have limited regenerative capacity due to their low cellularity and hypovascular nature, which results in poor clinical outcomes of presently used therapies. As tendon injuries are often observed in active adults, it poses an increasing socio-economic burden on healthcare systems. Currently, suture threads are used during surgical repair to anchor the tissue graft or to connect injured ends. Here, we created composite suture threads coated with a layer of cell-laden hydrogel that can be used for bridging the injured tissue aiming at tendon regeneration. In addition, the fibres can be used to engineer 3-dimensional constructs through textile processes mimicking the architecture and mechanical properties of soft tissues, including tendons and ligaments. Encapsulated human tendon-derived cells migrated within the hydrogel and aligned at the surface of the core thread. An up-regulation of tendon-related genes (scleraxis and tenascin C) and genes involved in matrix remodelling (matrix metalloproteinases 1, matrix metalloproteinases 2) was observed. Cells were able to produce a collagen-rich matrix, remodelling their micro-environment, which is structurally comparable to native tendon tissue. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Etiology and pathophysiology of tendon ruptures in sports.

    PubMed

    Kannus, P; Natri, A

    1997-04-01

    Of all spontaneous tendon ruptures, complete Achilles tendon tears are most closely associated with sports activities (1-3). Schönbauer (3) reported that 75% of all ruptures of the Achilles tendon are related to sports. In Plecko & Passl (2) the number was 60%. In our material of 430 cases, the number of sports-related Achilles ruptures was very similar (62%), while only 2% of ruptures of other tendons were sports-related (P < 0.001) (1). Also, the majority of Achilles reruptures occurred in sports. The ruptures occurred most often in soccer (34%), track and field (16%) and basketball (14%). The distribution of Achilles ruptures according to different sports varies considerably from country to country, according to the national sport traditions. For example, in northern and middle Europe, soccer, tennis, track and field, indoor ball games, downhill skiing, and gymnastics are the most common; and in North America, football, basketball, baseball, tennis and downhill skiing dominate the statistics (1, 2, 4). In sports, some Achilles ruptures are not spontaneous or degeneration-induced but may occur as a consequence of the remarkably high forces that are involved in the performance (2). Ruptures in the high jump or triple jump are good examples. In such cases, failure in the neuromuscular protective mechanisms due to fatigue or disturbed co-ordination can frequently be found. The spontaneous complete rupture of the supraspinatus tendon of the rotator cuff does not occur very frequently in sports. Those sports that include high-energy throwing movements, such as American and Finnish baseball, American football, rugby and discuss and javelin throwing, may, however, produce this injury. Partial tears and inflammations of the rotator cuff complex are much more frequent in throwing sports. The complete rupture of the proximal long head of the biceps brachii tendon is rare among competitive and recreational athletes. In our material, under 2% of these ruptures were

  1. Dental pulp stem cells express tendon markers under mechanical loading and are a potential cell source for tissue engineering of tendon-like tissue.

    PubMed

    Chen, Yu-Ying; He, Sheng-Teng; Yan, Fu-Hua; Zhou, Peng-Fei; Luo, Kai; Zhang, Yan-Ding; Xiao, Yin; Lin, Min-Kui

    2016-12-16

    Postnatal mesenchymal stem cells have the capacity to differentiate into multiple cell lineages. This study explored the possibility of dental pulp stem cells (DPSCs) for potential application in tendon tissue engineering. The expression of tendon-related markers such as scleraxis, tenascin-C, tenomodulin, eye absent homologue 2, collagens I and VI was detected in dental pulp tissue. Interestingly, under mechanical stimulation, these tendon-related markers were significantly enhanced when DPSCs were seeded in aligned polyglycolic acid (PGA) fibre scaffolds. Furthermore, mature tendon-like tissue was formed after transplantation of DPSC-PGA constructs under mechanical loading conditions in a mouse model. This study demonstrates that DPSCs could be a potential stem cell source for tissue engineering of tendon-like tissue.

  2. Tendon material properties vary and are interdependent among turkey hindlimb muscles

    PubMed Central

    Matson, Andrew; Konow, Nicolai; Miller, Samuel; Konow, Pernille P.; Roberts, Thomas J.

    2012-01-01

    SUMMARY The material properties of a tendon affect its ability to store and return elastic energy, resist damage, provide mechanical feedback and amplify or attenuate muscle power. While the structural properties of a tendon are known to respond to a variety of stimuli, the extent to which material properties vary among individual muscles remains unclear. We studied the tendons of six different muscles in the hindlimb of Eastern wild turkeys to determine whether there was variation in elastic modulus, ultimate tensile strength and resilience. A hydraulic testing machine was used to measure tendon force during quasi-static lengthening, and a stress–strain curve was constructed. There was substantial variation in tendon material properties among different muscles. Average elastic modulus differed significantly between some tendons, and values for the six different tendons varied nearly twofold, from 829±140 to 1479±106 MPa. Tendons were stretched to failure, and the stress at failure, or ultimate tensile stress, was taken as a lower-limit estimate of tendon strength. Breaking tests for four of the tendons revealed significant variation in ultimate tensile stress, ranging from 66.83±14.34 to 112.37±9.39 MPa. Resilience, or the fraction of energy returned in cyclic length changes was generally high, and one of the four tendons tested was significantly different in resilience from the other tendons (range: 90.65±0.83 to 94.02±0.71%). An analysis of correlation between material properties revealed a positive relationship between ultimate tensile strength and elastic modulus (r2=0.79). Specifically, stiffer tendons were stronger, and we suggest that this correlation results from a constrained value of breaking strain, which did not vary significantly among tendons. This finding suggests an interdependence of material properties that may have a structural basis and may explain some adaptive responses observed in studies of tendon plasticity. PMID:22771746

  3. It's positive to be negative: Achilles tendon work loops during human locomotion.

    PubMed

    Zelik, Karl E; Franz, Jason R

    2017-01-01

    Ultrasound imaging is increasingly used with motion and force data to quantify tendon dynamics during human movement. Frequently, tendon dynamics are estimated indirectly from muscle fascicle kinematics (by subtracting muscle from muscle-tendon unit length), but there is mounting evidence that this Indirect approach yields implausible tendon work loops. Since tendons are passive viscoelastic structures, when they undergo a loading-unloading cycle they must exhibit a negative work loop (i.e., perform net negative work). However, prior studies using this Indirect approach report large positive work loops, often estimating that tendons return 2-5 J of elastic energy for every 1 J of energy stored. More direct ultrasound estimates of tendon kinematics have emerged that quantify tendon elongations by tracking either the muscle-tendon junction or localized tendon tissue. However, it is unclear if these yield more plausible estimates of tendon dynamics. Our objective was to compute tendon work loops and hysteresis losses using these two Direct tendon kinematics estimates during human walking. We found that Direct estimates generally resulted in negative work loops, with average tendon hysteresis losses of 2-11% at 1.25 m/s and 33-49% at 0.75 m/s (N = 8), alluding to 0.51-0.98 J of tendon energy returned for every 1 J stored. We interpret this finding to suggest that Direct approaches provide more plausible estimates than the Indirect approach, and may be preferable for understanding tendon energy storage and return. However, the Direct approaches did exhibit speed-dependent trends that are not consistent with isolated, in vitro tendon hysteresis losses of about 5-10%. These trends suggest that Direct estimates also contain some level of error, albeit much smaller than Indirect estimates. Overall, this study serves to highlight the complexity and difficulty of estimating tendon dynamics non-invasively, and the care that must be taken to interpret biological function from

  4. [Ultrasound diagnostics of muscle and tendon injuries].

    PubMed

    Stević, Ruza; Masulović, Dragan

    2009-01-01

    Sonography is a useful technique for the investigation of a number of musculoskeletal disorders. The most common indication for ultrasonography of muscles and tendons is the diagnosis of traumatic lesions, distinguishing them from other disorders and follow- up of healing process. The purpose of this paper is to show the importance of ultrasound in the diagnosis of muscle and tendon injuries. The study included 170 patients (148 male and 22 female), mean age 29.6 years (range 14-60 years). All examinations were performed by linear transducer of 7.5-10 MHz, with longitudinal and transverse scanning. Ultrasound examination followed physical examination. Traumatic lesions of muscles were diagnosed in 113 patients (66.7%) and tendon injuries in 57 cases (33.2%). The muscle changes detected by ultrasonography were the following: 70 (61.9%) partial and two (1.76%) complete ruptures, 22 (19.46%) haematoma, 9 (7.96%) strains grade I, 4 fibroses and 4 ossifying myositis 4 (3.5%, respectively). Complications of muscle injuries were diagnosed in two cases, a muscular hernia and an arteriovenous fistula. Among tendon injuries, 21 (33.8%) ruptures and 36 (66.1%) tendinitis were diagnosed. Accompanying effusion in the bursa of patients with tendon injuries was found in 9 cases. Ultrasonography allowed visualization and objective assessment of the type and the extent of traumatic pathomorphological changes of muscles and tendons. Such diagnostic possibilities of ultrasonography are especially important in the choice of appropriate therapy.

  5. Central Tendon Injuries of Hamstring Muscles: Case Series of Operative Treatment.

    PubMed

    Lempainen, Lasse; Kosola, Jussi; Pruna, Ricard; Puigdellivol, Jordi; Sarimo, Janne; Niemi, Pekka; Orava, Sakari

    2018-02-01

    As compared with injuries involving muscle only, those involving the central hamstring tendon have a worse prognosis. Limited information is available regarding the surgical treatment of central tendon injuries of the hamstrings. To describe the operative treatment and outcomes of central tendon injuries of the hamstrings among athletes. Case series; Level of evidence, 4. Eight athletes (6 top level, 2 recreational) with central hamstring tendon injuries underwent magnetic resonance imaging and surgical treatment. The indication for surgery was recurrent (n = 6) or acute (n = 2) central hamstring tendon injury. All patients followed the same postoperative rehabilitation protocol, and return to play was monitored. Magnetic resonance imaging found a central tendon injury in all 3 hamstring muscles (long head of the biceps femoris, semimembranosus, and semitendinosus) with disrupted tendon ends. In acute and recurrent central tendon injuries, full return to play was achieved at 2.5 to 4 months. There were no adverse events during follow-up. Central tendon injuries of the hamstrings can be successfully repaired surgically after acute and recurrent ruptures.

  6. Central Tendon Injuries of Hamstring Muscles: Case Series of Operative Treatment

    PubMed Central

    Lempainen, Lasse; Kosola, Jussi; Pruna, Ricard; Puigdellivol, Jordi; Sarimo, Janne; Niemi, Pekka; Orava, Sakari

    2018-01-01

    Background: As compared with injuries involving muscle only, those involving the central hamstring tendon have a worse prognosis. Limited information is available regarding the surgical treatment of central tendon injuries of the hamstrings. Purpose: To describe the operative treatment and outcomes of central tendon injuries of the hamstrings among athletes. Study Design: Case series; Level of evidence, 4. Methods: Eight athletes (6 top level, 2 recreational) with central hamstring tendon injuries underwent magnetic resonance imaging and surgical treatment. The indication for surgery was recurrent (n = 6) or acute (n = 2) central hamstring tendon injury. All patients followed the same postoperative rehabilitation protocol, and return to play was monitored. Results: Magnetic resonance imaging found a central tendon injury in all 3 hamstring muscles (long head of the biceps femoris, semimembranosus, and semitendinosus) with disrupted tendon ends. In acute and recurrent central tendon injuries, full return to play was achieved at 2.5 to 4 months. There were no adverse events during follow-up. Conclusion: Central tendon injuries of the hamstrings can be successfully repaired surgically after acute and recurrent ruptures. PMID:29479545

  7. A rare knee extensor mechanism injury: Vastus intermedius tendon rupture.

    PubMed

    Cetinkaya, Engin; Aydin, Canan Gonen; Akman, Yunus Emre; Gul, Murat; Arikan, Yavuz; Aycan, Osman Emre; Kabukcuoglu, Yavuz Selim

    2015-01-01

    Quadriceps tendon injuries are rare. There is a limited number of studies in the literature, reporting partial quadriceps tendon ruptures. We did not find any study reporting an isolated vastus intermedius tendon injury in the literature. A 22 years old professional rugby player with the complaints of pain in the right lower limb, decreased range of motion in right knee and a mass in the mid-anterior of the right thigh applied following an overloading on his hyperflexed knee during a rugby match. T2 sequence magnetic resonance images revealed discontinuity in the vastus intermedius tendon and intramuscular hematoma. The patient has been conservatively treated. Quadriceps tendon ruptures generally occur after the 4th decade in the presence of degenerative changes. Our case is a young professional rugby player. Isolated vastus intermedius tendon rupture is unusual. Conservative treatment is performed as the intermedius tendon is in the deepest layer of the quadriceps muscle. We report the first case of isolated rupture of the vastus intermedius tendon in the literature and we claim that disorder may be succesfully treated with conservative treatment and adequate physiotheraphy. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. A rare knee extensor mechanism injury: Vastus intermedius tendon rupture

    PubMed Central

    Cetinkaya, Engin; Aydin, Canan Gonen; Akman, Yunus Emre; Gul, Murat; Arikan, Yavuz; Aycan, Osman Emre; Kabukcuoglu, Yavuz Selim

    2015-01-01

    Introduction Quadriceps tendon injuries are rare. There is a limited number of studies in the literature, reporting partial quadriceps tendon ruptures. We did not find any study reporting an isolated vastus intermedius tendon injury in the literature. Presentation of case A 22 years old professional rugby player with the complaints of pain in the right lower limb, decreased range of motion in right knee and a mass in the mid-anterior of the right thigh applied following an overloading on his hyperflexed knee during a rugby match. T2 sequence magnetic resonance images revealed discontinuity in the vastus intermedius tendon and intramuscular hematoma. The patient has been conservatively treated. Discussion Quadriceps tendon ruptures generally occur after the 4th decade in the presence of degenerative changes. Our case is a young professional rugby player. Isolated vastus intermedius tendon rupture is unusual. Conservative treatment is performed as the intermedius tendon is in the deepest layer of the quadriceps muscle. Conclusion We report the first case of isolated rupture of the vastus intermedius tendon in the literature and we claim that disorder may be succesfully treated with conservative treatment and adequate physiotheraphy. PMID:26298093

  9. The histology of tendon attachments to bone in man.

    PubMed Central

    Benjamin, M; Evans, E J; Copp, L

    1986-01-01

    Based on a parallel study of a wide range of human tendons from embalmed dissecting room subjects and from a study of dried bones, an explanation is offered for the well known similarity in gross appearance between the markings left by certain tendons (e.g. those of the rotator cuff) and by articular surfaces on dried bones. Epiphyseal tendons leave markings on bones that look like those left by articular surfaces. These tendons have a prominent zone of fibrocartilage at their attachment site and the deepest part of this is calcified, just as the deepest part of articular hyaline cartilage is calcified. After maceration of the soft tissues, the calcified (fibro) cartilage is left attached to the bone at articular surfaces and at the sites of tendon attachment. In all cases, the tissues separate at the basophilic tidemark between the calcified and uncalcified regions. This tidemark is smooth where there is much overlying uncalcified (fibro) cartilage and it is the smoothness that gives the typical appearance of the dried bone. Blood vessels do not generally traverse the tendon fibrocartilage plugs. Hence the areas are devoid of vascular foramina. The functional significance of tendon fibrocartilage is discussed with particular reference to supraspinatus. It is suggested that the uncalcified fibrocartilage ensures that the tendon fibres do not bend, splay out or become compressed at a hard tissue interface, and are thereby offered some protection from wear and tear. It is also suggested that the fibrocartilage plug of supraspinatus prevents the tendon from rubbing on the head of the humerus. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:3693113

  10. Tendon biomechanics and mechanobiology - a mini-review of basic concepts and recent advancements

    PubMed Central

    Wang, James H-C.; Guo, Qianping; Li, Bin

    2011-01-01

    Due to their unique hierarchical structure and composition, tendons possess characteristic biomechanical properties, including high mechanical strength and viscoelasticity, which enable them to carry and transmit mechanical loads (muscular forces) effectively. Tendons are also mechano-responsive by adaptively changing their structure and function in response to altered mechanical loading conditions. In general, mechanical loading at physiological levels is beneficial to tendons, but excessive loading or disuse of tendons is detrimental. This mechano-adaptability is due to the cells present in tendons. Tendon fibroblasts (tenocytes) are the dominant tendon cells responsible for tendon homeostasis and repair. Tendon stem cells (TSCs), which were recently discovered, also play a vital role in tendon maintenance and repair by virtue of their ability to self-renew and differentiate into tenocytes. TSCs may also be responsible for chronic tendon injury, or tendinopathy, by undergoing aberrant differentiation into non-tenocytes in response to excessive mechanical loading. Thus, it is necessary to devise optimal rehabilitation protocols in order to enhance tendon healing while reducing scar tissue formation and tendon adhesions. Moreover, along with scaffolds that can mimic tendon matrix environments and platelet-rich plasma (PRP), which serves as a source of growth factors, TSCs may be the optimal cell type for enhancing repair of injured tendons. PMID:21925835

  11. Contraction dynamics and function of the muscle-tendon complex depend on the muscle fibre-tendon length ratio: a simulation study.

    PubMed

    Mörl, Falk; Siebert, Tobias; Häufle, Daniel

    2016-02-01

    Experimental studies show different muscle-tendon complex (MTC) functions (e.g. motor or spring) depending on the muscle fibre-tendon length ratio. Comparing different MTC of different animals examined experimentally, the extracted MTC functions are biased by, for example, MTC-specific pennation angle and fibre-type distribution or divergent experimental protocols (e.g. influence of temperature or stimulation on MTC force). Thus, a thorough understanding of variation of these inner muscle fibre-tendon length ratios on MTC function is difficult. In this study, we used a hill-type muscle model to simulate MTC. The model consists of a contractile element (CE) simulating muscle fibres, a serial element (SE) as a model for tendon, and a parallel elastic element (PEE) modelling tissue in parallel to the muscle fibres. The simulation examines the impact of length variations of these components on contraction dynamics and MTC function. Ensuring a constant overall length of the MTC by L(MTC) = L(SE) + L(CE), the SE rest length was varied over a broad physiological range from 0.1 to 0.9 MTC length. Five different MTC functions were investigated by simulating typical physiological experiments: the stabilising function with isometric contractions, the motor function with contractions against a weight, the capability of acceleration with contractions against a small inertial mass, the braking function by decelerating a mass, and the spring function with stretch-shortening cycles. The ratio of SE and CE mainly determines the MTC function. MTC with comparably short tendon generates high force and maximal shortening velocity and is able to produce maximal work and power. MTC with long tendon is suitable to store and release a maximum amount of energy. Variation of muscle fibre-tendon ratio yielded two peaks for MTC's force response for short and long SE lengths. Further, maximum work storage capacity of the SE is at long relL(SE,0). Impact of fibre-tendon length ratio on MTC

  12. Dedicated ultrasound speckle tracking to study tendon displacement

    NASA Astrophysics Data System (ADS)

    Korstanje, Jan-Wiebe H.; Selles, Ruud W.; Stam, Henk J.; Hovius, Steven E. R.; Bosch, Johan G.

    2009-02-01

    Ultrasound can be used to study tendon and muscle movement. However, quantization is mostly based on manual tracking of anatomical landmarks such as the musculotendinous junction, limiting the applicability to a small number of muscle-tendon units. The aim of this study is to quantify tendon displacement without employing anatomical landmarks, using dedicated speckle tracking in long B-mode image sequences. We devised a dedicated two-dimensional multikernel block-matching scheme with subpixel accuracy to handle large displacements over long sequences. Images were acquired with a Philips iE33 with a 7 MHz linear array and a VisualSonics Vevo 770 using a 40 MHz mechanical probe. We displaced the flexor digitorum superficialis of two pig cadaver forelegs with three different velocities (4,10 and 16 mm/s) over 3 distances (5, 10, 15 mm). As a reference, we manually determined the total displacement of an injected hyperechogenic bullet in the tendons. We automatically tracked tendon parts with and without markers and compared results to the true displacement. Using the iE33, mean tissue displacement underestimations for the three different velocities were 2.5 +/- 1.0%, 1.7 +/- 1.1% and 0.7 +/- 0.4%. Using the Vevo770, mean tissue displacement underestimations were 0.8 +/- 1.3%, 0.6 +/- 0.3% and 0.6 +/- 0.3%. Marker tracking displacement underestimations were only slightly smaller, showing limited tracking drift for non-marker tendon tissue as well as for markers. This study showed that our dedicated speckle tracking can quantify extensive tendon displacement with physiological velocities without anatomical landmarks with good accuracy for different types of ultrasound configurations. This technique allows tracking of a much larger range of muscle-tendon units than by using anatomical landmarks.

  13. Relationship between chronic pathologies of the supraspinatus tendon and the long head of the biceps tendon: systematic review.

    PubMed

    Redondo-Alonso, Lucía; Chamorro-Moriana, Gema; Jiménez-Rejano, José Jesús; López-Tarrida, Patricio; Ridao-Fernández, Carmen

    2014-11-18

    Chronic supraspinatus tendinopathy is a common clinical problem that causes functional and labor disabilities in the population. It is the most frequent cause of shoulder pain. This pathology may be frequently associated to the affectation of the long head of biceps tendon (LHBT), the main stabilizer of the glenohumeral joint together with the supraspinatus. The main aim of this work is to study the prevalence of lesions in LHBT associated to the chronic pathology of the supraspinatus tendon. A systematic review was carried out between May to July 2013 in the electronic databases: CINAHL, WOK, Medline, Scopus, PEDro, IME (CSIC) and Dialnet. The keywords used were: 1) in English: chronic, supraspinatus "long head of the biceps tendon", biceps, rotator cuff, tendinosis, tendinopathy, evaluation, examination; 2) in Spanish: supraespinoso, biceps, tendinopatía. Inclusion criteria of the articles included subjects with a previously diagnosed chronic pathology of rotator cuff (RC) without previous surgery or any other pathologies of the shoulder complex. The total number of articles included in the study were five. The results show an epidemiological relationship between both tendons. The age of the subjects included in the review was between 35 and 80 years, and some of the studies seem to indicate that the tendinopathy is more frequent in men than in women. The sample size of the studies varies according to the design, the highest being composed of 229 subjects, and the minimum of 28. Not all the articles selected specify the diagnostic testing, though the ones most normally used are arthroscopy, ultrasound, magnetic resonance imaging and assessment tests. The percentage of associated lesions of LHBT and supraspinatus tendon is between 78.5% and 22%, with a major prevalence in the studies with a smaller sample. The review of literature corroborates an association between the chronic pathology of the supraspinatus tendon and LHBT due to the epidemiological data. In

  14. Preinjury and postinjury running analysis along with measurements of strength and tendon length in a patient with a surgically repaired Achilles tendon rupture.

    PubMed

    Silbernagel, Karin Grävare; Willy, Richard; Davis, Irene

    2012-06-01

    Case report. The Achilles tendon is the most frequently ruptured tendon, and the incidence of Achilles tendon rupture has increased in the last decade. The rupture generally occurs without any preceding warning signs, and therefore preinjury data are seldom available. This case represents a unique opportunity to compare preinjury running mechanics with postinjury evaluation in a patient with an Achilles tendon rupture. A 23-year-old female sustained a right complete Achilles tendon rupture while playing soccer. Running mechanics data were collected preinjury, as she was a healthy participant in a study on running analysis. In addition, patient-reported symptoms, physical activity level, strength, ankle range of motion, heel-rise ability, Achilles tendon length, and running kinetics were evaluated 1 year after surgical repair. During running, greater ankle dorsiflexion and eversion and rearfoot abduction were noted on the involved side postinjury when compared to preinjury data. In addition, postinjury, the magnitude of all kinetics data was lower on the involved limb when compared to the uninvolved limb. The involved side displayed differences in strength, ankle range of motion, heel rise, and tendon length when compared to the uninvolved side 1 year after injury. Despite a return to normal running routine and reports of only minor limitations with running, considerable changes were noted in running biomechanics 1 year after injury. Calf muscle weakness and Achilles tendon elongation were also found when comparing the involved and uninvolved sides.

  15. System and Method for Tensioning a Robotically Actuated Tendon

    NASA Technical Reports Server (NTRS)

    Reiland, Matthew J. (Inventor); Diftler, Myron A. (Inventor)

    2013-01-01

    A tendon tensioning system includes a tendon having a proximal end and a distal end, an actuator, and a motor controller. The actuator may include a drive screw and a motor, and may be coupled with the proximal end of the tendon and configured to apply a tension through the tendon in response to an electrical current. The motor controller may be electrically coupled with the actuator, and configured to provide an electrical current having a first amplitude to the actuator until a stall tension is achieved through the tendon; provide a pulse current to the actuator following the achievement of the stall tension, where the amplitude of the pulse current is greater than the first amplitude, and return the motor to a steady state holding current following the conclusion of the pulse current.

  16. Cellular therapy in bone-tendon interface regeneration

    PubMed Central

    Rothrauff, Benjamin B; Tuan, Rocky S

    2014-01-01

    The intrasynovial bone-tendon interface is a gradual transition from soft tissue to bone, with two intervening zones of uncalcified and calcified fibrocartilage. Following injury, the native anatomy is not restored, resulting in inferior mechanical properties and an increased risk of re-injury. Recent in vivo studies provide evidence of improved healing when surgical repair of the bone-tendon interface is augmented with cells capable of undergoing chondrogenesis. In particular, cellular therapy in bone-tendon healing can promote fibrocartilage formation and associated improvements in mechanical properties. Despite these promising results in animal models, cellular therapy in human patients remains largely unexplored. This review highlights the development and structure-function relationship of normal bone-tendon insertions. The natural healing response to injury is discussed, with subsequent review of recent research on cellular approaches for improved healing. Finally, opportunities for translating in vivo findings into clinical practice are identified. PMID:24326955

  17. In vitro structural properties of braided tendon grafts.

    PubMed

    Nicklin, S; Waller, C; Walker, P; Chung, W K; Walsh, W R

    2000-01-01

    In an effort to increase strength in hamstring tendon grafts for anterior cruciate ligament reconstruction, braiding or weaving of the tendons has been suggested. The purpose of this study was to examine the biomechanical properties of two braiding techniques compared with a four-stranded tendon graft using a sheep model. Digital extensor tendons from 5 adult sheep were harvested in 28 matched pairs and randomly allocated to French plait or four-stranded weave. The grafts were tested in a hydraulic testing machine with the tendons secured in brass grips frozen with liquid carbon dioxide. The tendons were preconditioned to a distraction of 1 mm for 10 cycles followed by testing to failure at 50 mm/sec, with a data acquisition rate of 1,000 Hz. The stiffness, ultimate load to failure, and the mode of failure were recorded. All braided samples failed at the midsubstance, while the four-stranded controls failed at the grip interface. There was a significant reduction in strength and stiffness of the braided samples compared with the controls. This study demonstrated that braiding decreases the strength and stiffness of a four-stranded tendon graft by up to 54% and 85%, respectively. This finding is supported by the work of Hearle et al. (1969), who demonstrated that the decrease in strength of fiber bundles is equal to the square of the cosine of the twist angle. The twist angle in our samples was approximately 45 degrees, which equates to a decrease in strength of 50%.

  18. Pleiotropic roles of the matricellular protein Sparc in tendon maturation and ageing

    PubMed Central

    Gehwolf, Renate; Wagner, Andrea; Lehner, Christine; Bradshaw, Amy D.; Scharler, Cornelia; Niestrawska, Justyna A.; Holzapfel, Gerhard A.; Bauer, Hans-Christian; Tempfer, Herbert; Traweger, Andreas

    2016-01-01

    Acute and chronic tendinopathies remain clinically challenging and tendons are predisposed to degeneration or injury with age. Despite the high prevalence of tendon disease in the elderly, our current understanding of the mechanisms underlying the age-dependent deterioration of tendon function remains very limited. Here, we show that Secreted protein acidic and rich in cysteine (Sparc) expression significantly decreases in healthy-aged mouse Achilles tendons. Loss of Sparc results in tendon collagen fibrillogenesis defects and Sparc−/− tendons are less able to withstand force in comparison with their respective wild type counterparts. On the cellular level, Sparc-null and healthy-aged tendon-derived cells exhibited a more contracted phenotype and an altered actin cytoskeleton. Additionally, an elevated expression of the adipogenic marker genes PPARγ and Cebpα with a concomitant increase in lipid deposits in aged and Sparc−/− tendons was observed. In summary, we propose that Sparc levels in tendons are critical for proper collagen fibril maturation and its age-related decrease, together with a change in ECM properties favors lipid accretion in tendons. PMID:27586416

  19. Peroneal Tendon Reconstruction and Coverage for Treatment of Septic Peroneal Tenosynovitis: A Devastating Complication of Lateral Ankle Ligament Reconstruction With a Tendon Allograft.

    PubMed

    Schade, Valerie L; Harsha, Wayne; Rodman, Caitlin; Roukis, Thomas S

    2016-01-01

    Septic peroneal tenosynovitis is a rare and significant challenge. A search of peer-reviewed published studies revealed only 5 case reports to guide treatment, none of which resulted in significant loss of both peroneal tendons necessitating reconstruction. No clear guidance is available regarding how to provide reliable reconstruction of both peroneal tendons after a significant loss secondary to septic tenosynovitis. In the present report, we describe the case of a young, active-duty soldier who underwent lateral ankle ligament reconstruction with a tendon allograft whose postoperative course was complicated by septic peroneal tenosynovitis resulting in significant loss of both peroneal tendons. Reconstruction was achieved in a staged fashion with the use of silicone rods and external fixation to maintain physiologic tension and preserve peroneal tendon function, followed by reconstruction of both peroneal tendons and the superior peroneal retinaculum with a tensor fascia lata autograft. Soft tissue coverage was obtained with an anterolateral thigh free tissue transfer and a split-thickness skin graft. The patient returned to full activity as an active-duty soldier with minimal pain and no instability of the right lower extremity. The muscle strength of both peroneal tendons remained at 5 of 5, and no objective findings of ankle instability were seen at 3.5 years postoperatively. Published by Elsevier Inc.

  20. Differences between the Cell Populations from the Peritenon and the Tendon Core with Regard to Their Potential Implication in Tendon Repair

    PubMed Central

    Cadby, Jennifer A.; Buehler, Evelyne; Godbout, Charles; van Weeren, P. René; Snedeker, Jess G.

    2014-01-01

    The role of intrinsic and extrinsic healing in injured tendons is still debated. In this study, we characterized cell plasticity, proliferative capacity, and migration characteristics as proxy measures of healing potential in cells derived from the peritenon (extrinsic healing) and compared these to cells from the tendon core (intrinsic healing). Both cell populations were extracted from horse superficial digital flexor tendon and characterized for tenogenic and matrix remodeling markers as well as for rates of migration and replication. Furthermore, colony-forming unit assays, multipotency assays, and real-time quantitative polymerase chain reaction analyses of markers of osteogenic and adipogenic differentiation after culture in induction media were performed. Finally, cellular capacity for differentiation towards a myofibroblastic phenotype was assessed. Our results demonstrate that both tendon- and peritenon-derived cell populations are capable of adipogenic and osteogenic differentiation, with higher expression of progenitor cell markers in peritenon cells. Cells from the peritenon also migrated faster, replicate more quickly, and show higher differentiation potential toward a myofibroblastic phenotype when compared to cells from the tendon core. Based on these data, we suggest that cells from the peritenon have substantial potential to influence tendon-healing outcome, warranting further scrutiny of their role. PMID:24651449

  1. Tendon and ligament injuries: the genetic component

    PubMed Central

    September, Alison V; Schwellnus, Martin P; Collins, Malcolm

    2007-01-01

    Tendons and ligaments within the upper and lower limbs are some of the more common sites of musculoskeletal injuries during physical activity. Several extrinsic and intrinsic factors have been shown to be associated with these injuries. More recently, studies have suggested that there is also, at least in part, a genetic component to the Achilles tendon, rotator cuff and anterior cruciate ligament injuries. However, specific genes have not been suggested to be associated with rotator cuff or anterior cruciate ligament injuries. Sequence variants of the tenascin C (TNC) gene, on the other hand, have been shown to be associated with Achilles tendinopathies and Achilles tendon ruptures, whereas a variant of the collagen V α 1 (COL5A1) gene has also been shown to be associated with Achilles tendinopathies. Both genes encode for important structural components of tendons and ligaments. The COL5A1 gene encodes for a component of type V collagen, which has an important role in regulating collagen fibre assembly and fibre diameters. The TNC gene, on the other hand, encodes for TNC, which regulates the tissue's response to mechanical load. To date, only variants in two genes have been shown to be associated with Achilles tendon injuries. In addition, although specific genes have not been identified, investigators have suggested that there is also a genetic component to both rotator cuff and anterior cruciate ligament injuries. In future, specific genotypes associated with increased risk of injury to specific tendons and ligaments can prevent these injuries by identifying individuals at higher risk. PMID:17261551

  2. Different Achilles Tendon Pathologies Show Distinct Histological and Molecular Characteristics

    PubMed Central

    Minkwitz, Susann; Schmock, Aysha; Bormann, Nicole; Kurtoglu, Alper; Tsitsilonis, Serafeim; Manegold, Sebastian

    2018-01-01

    Reasons for the development of chronic tendon pathologies are still under debate and more basic knowledge is needed about the different diseases. The aim of the present study was therefore to characterize different acute and chronic Achilles tendon disorders. Achilles tendon samples from patients with chronic tendinopathy (n = 7), chronic ruptures (n = 6), acute ruptures (n = 13), and intact tendons (n = 4) were analyzed. The histological score investigating pathological changes was significantly increased in tendinopathy and chronic ruptures compared to acute ruptures. Inflammatory infiltration was detected by immunohistochemistry in all tendon pathology groups, but was significantly lower in tendinopathy compared to chronic ruptures. Quantitative real-time PCR (qRT-PCR) analysis revealed significantly altered expression of genes related to collagens and matrix modeling/remodeling (matrix metalloproteinases, tissue inhibitors of metalloproteinases) in tendinopathy and chronic ruptures compared to intact tendons and/or acute ruptures. In all three tendon pathology groups markers of inflammation (interleukin (IL) 1β, tumor necrosis factor α, IL6, IL10, IL33, soluble ST2, transforming growth factor β1, cyclooxygenase 2), inflammatory cells (cluster of differentaition (CD) 3, CD68, CD80, CD206), fat metabolism (fatty acid binding protein 4, peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α, adiponectin), and innervation (protein gene product 9.5, growth associated protein 43, macrophage migration inhibitory factor) were detectable, but only in acute ruptures significantly regulated compared to intact tendons. The study gives an insight into structural and molecular changes of pathological processes in tendons and might be used to identify targets for future therapy of tendon pathologies. PMID:29385715

  3. Landing strategies of athletes with an asymptomatic patellar tendon abnormality.

    PubMed

    Edwards, Suzi; Steele, Julie R; McGhee, Deirdre E; Beattie, Sue; Purdam, Craig; Cook, Jill L

    2010-11-01

    Risk factors associated with a clinical presentation of patellar tendinopathy are patellar tendon ultrasonographic abnormality (PTA) and excessive loading. It remains unknown whether characteristics of an athlete's landing technique contribute to this excessive patellar tendon loading. This study investigated whether asymptomatic athletes with and without PTA had different landing strategies and hypothesized that asymptomatic athletes with a PTA would create higher patellar tendon loading and a different lower-limb landing strategy compared with athletes with normal patellar tendons. Seven athletes with no previous history or clinical signs of patellar tendon injury with a PTA were matched to athletes with normal patellar tendons (controls). Participants performed five successful trials of a stop-jump task, which involved a simultaneous two-foot horizontal and then vertical landing. During each trial, the participants' ground reaction forces and lower-limb electromyographic data were recorded, the three-dimensional kinematics measured, and the peak patellar tendon force calculated by dividing the net knee joint moment by the patellar tendon moment arm. Significant between-group differences in landing technique were mostly observed during the horizontal landing phase. Participants with a PTA created similar patellar tendon loading to the controls, but with altered sequencing, by landing with significantly greater knee flexion and extending their hips while the controls flexed their hips as they landed, reflecting a different muscle recruitment order compared with the PTA group. The crucial part in the development of PTA and, in turn, patellar tendinopathy may not be the magnitude of the patellar tendon load but rather the loading patterns. This research provides clinicians with important landing assessment criteria against which to identify athletes at risk of developing patellar tendinopathy.

  4. Myostatin dysfunction impairs force generation in extensor digitorum longus muscle and increases exercise-induced protein efflux from extensor digitorum longus and soleus muscles.

    PubMed

    Baltusnikas, Juozas; Kilikevicius, Audrius; Venckunas, Tomas; Fokin, Andrej; Bünger, Lutz; Lionikas, Arimantas; Ratkevicius, Aivaras

    2015-08-01

    Myostatin dysfunction promotes muscle hypertrophy, which can complicate assessment of muscle properties. We examined force generating capacity and creatine kinase (CK) efflux from skeletal muscles of young mice before they reach adult body and muscle size. Isolated soleus (SOL) and extensor digitorum longus (EDL) muscles of Berlin high (BEH) mice with dysfunctional myostatin, i.e., homozygous for inactivating myostatin mutation, and with a wild-type myostatin (BEH+/+) were studied. The muscles of BEH mice showed faster (P < 0.01) twitch and tetanus contraction times compared with BEH+/+ mice, but only EDL displayed lower (P < 0.05) specific force. SOL and EDL of age-matched but not younger BEH mice showed greater exercise-induced CK efflux compared with BEH+/+ mice. In summary, myostatin dysfunction leads to impairment in muscle force generating capacity in EDL and increases susceptibility of SOL and EDL to protein loss after exercise.

  5. Proximal Biceps Tendonitis

    MedlinePlus

    ... teens, biceps tendonitis is usually an overuse injury. Baseball pitchers, swimmers, tennis players, and people who have ... But if you swim or play tennis or baseball, that might not be an option! If your ...

  6. Extensor Tendon Injuries

    MedlinePlus

    ... the Hand. Find a hand surgeon near you. Videos Figures Figure 1 - Extensor tendons, located on the ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

  7. Tendon Transfer Surgery

    MedlinePlus

    ... Transfer Surgery Find a hand surgeon near you. Videos Figures Figure 2: Example of Tendon Transfer surgery ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

  8. Flexor Tendon Injuries

    MedlinePlus

    ... the Hand. Find a hand surgeon near you. Videos Figures Figure 1 -The tendons of the hand ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

  9. The effect of muscle excursion on muscle recovery after tendon repair in a neglected tendon injury: a study in rabbit soleus muscles.

    PubMed

    Jeon, Suk Ha; Chung, Moon Sang; Baek, Goo Hyun; Lee, Young Ho; Gong, Hyun Sik

    2011-01-01

    We attempted to determine whether muscle excursion observed during operation can be a prognostic indicator of muscle recovery after delayed tendon repair in a rabbit soleus model. Eighteen rabbits underwent tenotomy of the soleus muscles bilaterally and were divided into three groups according to the period from tenotomy to repair. The tendons of each group were repaired 2, 4, and 6 weeks after tenotomy. The excursion of each soleus muscle was measured at the time of tenotomy (baseline), at 2, 4, 6 weeks after tenotomy, and 8 weeks after tendon repair. The amount of muscle recovery after tendon repair in terms of muscle excursion independently depended on the timing of repair and on the muscle excursion observed during repair. The regression model predicted that the muscle excursion recovered on average by 0.6% as the muscle excursion at the time of repair increased by 1% after adjusting for the timing of repair. This study suggests that measuring the muscle excursion during tendon repair may help physicians estimate the potential of muscle recovery in cases of delayed tendon repair. Copyright © 2010 Orthopaedic Research Society.

  10. Quantitative US Elastography Can Be Used to Quantify Mechanical and Histologic Tendon Healing in a Rabbit Model of Achilles Tendon Transection.

    PubMed

    Yamamoto, Yohei; Yamaguchi, Satoshi; Sasho, Takahisa; Fukawa, Taisuke; Akatsu, Yorikazu; Akagi, Ryuichiro; Yamaguchi, Tadashi; Takahashi, Kenji; Nagashima, Kengo; Takahashi, Kazuhisa

    2017-05-01

    Purpose To determine the time-dependent change in strain ratios (SRs) at the healing site of an Achilles tendon rupture in a rabbit model of tendon transection and to assess the correlation between SRs and the mechanical and histologic properties of the healing tissue. Materials and Methods Experimental methods were approved by the institutional animal care and use committee. The Achilles tendons of 24 New Zealand white rabbits (48 limbs) were surgically transected. The SRs of Achilles tendons were calculated by using compression-based quantitative ultrasonographic elastography measurements obtained 2, 4, 8, and 12 weeks after transection. After in vivo elastography, the left Achilles tendon was harvested for mechanical testing of ultimate load, ultimate stress, elastic modulus, and linear stiffness, and the right tendons were harvested for tissue histologic analysis with the Bonar scale. Time-dependent changes in SRs, mechanical parameters, and Bonar scale scores were evaluated by using repeated-measures analysis of variance. The correlation between SRs and each measured variable was evaluated by using the Spearman rank correlation coefficient. Results Mean SRs and Bonar scale values decreased as a function of time after transection, whereas mechanical parameters increased (P < .001). SR correlated with ultimate stress (ρ = 0.68, P <.001,) elastic modulus (ρ = 0.74, P <.001), and the Bonar scale (ρ = 0.87, P <.001). Conclusion Quantitative elastography could be a useful method with which to evaluate mechanical and histologic properties of the healing tendon. © RSNA, 2017 Online supplemental material is available for this article.

  11. HGF Mediates the Anti-inflammatory Effects of PRP on Injured Tendons

    PubMed Central

    Zhang, Jianying; Middleton, Kellie K.; Fu, Freddie H.; Im, Hee-Jeong; Wang, James H-C.

    2013-01-01

    Platelet-rich plasma (PRP) containing hepatocyte growth factor (HGF) and other growth factors are widely used in orthopaedic/sports medicine to repair injured tendons. While PRP treatment is reported to decrease pain in patients with tendon injury, the mechanism of this effect is not clear. Tendon pain is often associated with tendon inflammation, and HGF is known to protect tissues from inflammatory damages. Therefore, we hypothesized that HGF in PRP causes the anti-inflammatory effects. To test this hypothesis, we performed in vitro experiments on rabbit tendon cells and in vivo experiments on a mouse Achilles tendon injury model. We found that addition of PRP or HGF decreased gene expression of COX-1, COX-2, and mPGES-1, induced by the treatment of tendon cells in vitro with IL-1β. Further, the treatment of tendon cell cultures with HGF antibodies reduced the suppressive effects of PRP or HGF on IL-1β-induced COX-1, COX-2, and mPGES-1 gene expressions. Treatment with PRP or HGF almost completely blocked the cellular production of PGE2 and the expression of COX proteins. Finally, injection of PRP or HGF into wounded mouse Achilles tendons in vivo decreased PGE2 production in the tendinous tissues. Injection of platelet-poor plasma (PPP) however, did not reduce PGE2 levels in the wounded tendons, but the injection of HGF antibody inhibited the effects of PRP and HGF. Further, injection of PRP or HGF also decreased COX-1 and COX-2 proteins. These results indicate that PRP exerts anti-inflammatory effects on injured tendons through HGF. This study provides basic scientific evidence to support the use of PRP to treat injured tendons because PRP can reduce inflammation and thereby reduce the associated pain caused by high levels of PGE2. PMID:23840657

  12. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Passive tendon prosthesis. 888.3025 Section 888.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3025 Passive tendon prosthesis. (a...

  13. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Passive tendon prosthesis. 888.3025 Section 888.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3025 Passive tendon prosthesis. (a...

  14. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Passive tendon prosthesis. 888.3025 Section 888.3025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3025 Passive tendon prosthesis. (a...

  15. The role of ultrasound in the management of flexor tendon injuries.

    PubMed

    Jeyapalan, K; Bisson, M A; Dias, J J; Griffin, Y; Bhatt, R

    2008-08-01

    The use of ultrasound scanning to establish tendon pathologies was assessed retrospectively in 17 patients in 18 digits. The ultrasound scan demonstrated four patterns: (1) normal intact tendons in four, (2) ruptured tendons in three, (3) tendons in continuity but attenuated in five and (4) tendons in continuity but thickened with fibrosis and decreased movement representing adhesions in five patients. Surgery was undertaken in only three cases, confirming the ultrasound diagnosis in two. Surgery was offered to all three patients with ruptures but was declined by two. Ultrasound imaging helped to avoid surgery in 14 cases by excluding flexor tendon re-ruptures. This allowed on-going mobilisation, leading to recovery of function.

  16. Distal Triceps Tendon Injuries.

    PubMed

    Keener, Jay D; Sethi, Paul M

    2015-11-01

    Acute triceps ruptures are an uncommon entity, occurring mainly in athletes, weight lifters (especially those taking anabolic steroids), and following elbow trauma. Accurate diagnosis is made clinically, although MRI may aid in confirmation and surgical planning. Acute ruptures are classified on an anatomic basis based on tear location and the degree of tendon involvement. Most complete tears are treated surgically in medically fit patients. Partial-thickness tears are managed according to the tear severity, functional demands, and response to conservative treatment. We favor an anatomic footprint repair of the triceps to provide optimal tendon to bone healing and, ultimately, functional outcome. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Quadriceps Tendon Autograft Medial Patellofemoral Ligament Reconstruction.

    PubMed

    Fink, Christian; Steensen, Robert; Gföller, Peter; Lawton, Robert

    2018-06-01

    Critically evaluate the published literature related to quadriceps tendon (QT) medial patellofemoral ligament (MPFL) reconstruction. Hamstring tendon (HT) MPFL reconstruction techniques have been shown to successfully restore patella stability, but complications including patella fracture are reported. Quadriceps tendon (QT) reconstruction techniques with an intact graft pedicle on the patella side have the advantage that patella bone tunnel drilling and fixation are no longer needed, reducing risk of patella fracture. Several QT MPFL reconstruction techniques, including minimally invasive surgical (MIS) approaches, have been published with promising clinical results and fewer complications than with HT techniques. Parallel laboratory studies have shown macroscopic anatomy and biomechanical properties of QT are more similar to native MPFL than hamstring (HS) HT, suggesting QT may more accurately restore native joint kinematics. Quadriceps tendon MPFL reconstruction, via both open and MIS techniques, have promising clinical results and offer valuable alternatives to HS grafts for primary and revision MPFL reconstruction in both children and adults.

  18. Effects of celecoxib on proliferation and tenocytic differentiation of tendon-derived stem cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Kairui; Zhang, Sheng; Li, Qianqian

    Highlights: • Celecoxib has no effects on TDSCs cell proliferation in various concentrations. • Celecoxib reduced mRNAs levels of tendon associated transcription factor. • Celecoxib reduced mRNAs levels of main tendon associated collagen. • Celecoxib reduced mRNAs levels of tendon associated molecules. - Abstract: NSAIDs are often ingested to reduce the pain and improve regeneration of tendon after tendon injury. Although the effects of NSAIDs in tendon healing have been reported, the data and conclusions are not consistent. Recently, tendon-derived stem cells (TDSCs) have been isolated from tendon tissues and has been suggested involved in tendon repair. Our study aimsmore » to determine the effects of COX-2 inhibitor (celecoxib) on the proliferation and tenocytic differentiation of TDSCs. TDSCs were isolated from mice Achilles tendon and exposed to celecoxib. Cell proliferation rate was investigated at various concentrations (0.1, 1, 10 and 100 μg/ml) of celecoxib by using hemocytometer. The mRNA expression of tendon associated transcription factors, tendon associated collagens and tendon associated molecules were determined by reverse transcription-polymerase chain reaction. The protein expression of Collagen I, Collagen III, Scleraxis and Tenomodulin were determined by Western blotting. The results showed that celecoxib has no effects on TDSCs cell proliferation in various concentrations (p > 0.05). The levels of most tendon associated transcription factors, tendon associated collagens and tendon associated molecules genes expression were significantly decreased in celecoxib (10 μg/ml) treated group (p < 0.05). Collagen I, Collagen III, Scleraxis and Tenomodulin protein expression were also significantly decreased in celecoxib (10 μg/ml) treated group (p < 0.05). In conclusion, celecoxib inhibits tenocytic differentiation of tendon-derived stem cells but has no effects on cell proliferation.« less

  19. Endoscopy-assisted percutaneous repair of acute Achilles tendon tears.

    PubMed

    Chiu, Chih-Hao; Yeh, Wen-Lin; Tsai, Min-Chien; Chang, Shih-Sheng; Hsu, Kuo-Yao; Chan, Yi-Sheng

    2013-08-01

    We developed a technique for endoscopy-assisted percutaneous repair of acute Achilles tendon tears. Nineteen patients with acute Achilles tendon tears were prospectively recruited into the study. All patients (18 male, 1 female) had sports-related injuries. Preoperative diagnosis was made from patient history, physical examination, and sonography. The average patient age was 38.7 years, and follow-up averaged 24 months. All patients received endoscopy-assisted percutaneous Achilles tendon repair with modified Bunnell sutures passed by bird beak and No. 5 Ethibond under direct visualization using 4.0-mm arthroscopy. Results were evaluated by physical examination, sonography, and magnetic resonance imaging (MRI). All 19 patients achieved tendon healing. All patients were evaluated by sonography, and the tendons of 16 patients were imaged using MRI to evaluate the extent of healing. Final dorsiflexion was 16 degrees and plantar flexion 26 degrees, and 95% of the patients (18/19) returned to their previous level of sporting activity. One patient developed a superficial infection, and 2 patients had postoperative sural nerve injury with numbness for 1 month. There were no other major complications. Endoscopy-assisted percutaneous repair of the Achilles tendon allowed good tendon healing and return to sports at 6 months. Sural nerve injury during surgery was a potential complication of this procedure. Level IV, retrospective case series.

  20. The Achilles Tendon in Healthy Subjects: An Anthropometric and Ultrasound Mapping Study.

    PubMed

    Patel, Nick N; Labib, Sameh A

    Ultrasonography is an inexpensive, fast, and reliable imaging technique widely used to assess the Achilles tendon. Although significant data exists regarding pathologic tendon changes, ultrasound data from healthy individuals are more limited. We aimed to better characterize ultrasound Achilles tendon measurements in healthy individuals and identify important correlating factors. The information collected included patient demographics, body habitus, activity level, foot dominance, and resting ankle angle. Ultrasound analysis was performed bilaterally on the Achilles tendons of 50 subjects using a high-frequency transducer to measure tendon width, thickness, cross-sectional area, and length. Males had a significantly larger mean tendon length, width, thickness, and cross-sectional area. No statistically significant difference was found in any tendon dimension between the white and black participants. Similarly, no difference was found in any tendon parameter when comparing right versus left leg dominance. Healthy subjects had a mean ankle resting angle of 45.1° ± 24° with no statistically significant difference between right and left ankles. Considering all individuals, each tendon parameter (tendon length, width, thickness, and cross-sectional area) correlated positively with subject height, weight, tibia length, and foot size. Only the Achilles cross-sectional area correlated significantly with the activity level. The resting angle of the ankle correlated positively with both tendon length and thickness. In conclusion, we found significant variations in Achilles tendon anatomy in the healthy adult population. We have thoroughly characterized significant correlations between healthy tendon dimensions and various body habitus, activity levels, and ankle parameters. Greater knowledge of the normal Achilles tendon anatomy and characterization of its variations in the healthy population will potentially allow for better pathologic diagnosis and surgical repair

  1. Achilles tendon shape and echogenicity on ultrasound among active badminton players.

    PubMed

    Malliaras, P; Voss, C; Garau, G; Richards, P; Maffulli, N

    2012-04-01

    The relationship between Achilles tendon ultrasound abnormalities, including a spindle shape and heterogeneous echogenicity, is unclear. This study investigated the relationship between these abnormalities, tendon thickness, Doppler flow and pain. Sixty-one badminton players (122 tendons, 36 men, and 25 women) were recruited. Achilles tendon thickness, shape (spindle, parallel), echogenicity (heterogeneous, homogeneous) and Doppler flow (present or absent) were measured bilaterally with ultrasound. Achilles tendon pain (during or after activity over the last week) and pain and function [Victorian Institute of Sport Achilles Assessment (VISA-A)] were measured. Sixty-eight (56%) tendons were parallel with homogeneous echogenicity (normal), 22 (18%) were spindle shaped with homogeneous echogenicity, 16 (13%) were parallel with heterogeneous echogenicity and 16 (13%) were spindle shaped with heterogeneous echogenicity. Spindle shape was associated with self-reported pain (P<0.05). Heterogeneous echogenicity was associated with lower VISA-A scores than normal tendon (P<0.05). There was an ordinal relationship between normal tendon, parallel and heterogeneous and spindle shaped and heterogeneous tendons with regard to increasing thickness and likelihood of Doppler flow. Heterogeneous echogenicity with a parallel shape may be a physiological phase and may develop into heterogeneous echogenicity with a spindle shape that is more likely to be pathological. © 2010 John Wiley & Sons A/S.

  2. Tensile properties of craniofacial tendons in the mature and aged zebrafish

    PubMed Central

    Shah, Rishita R.; Nerurkar, Nandan L.; Wang, Calvin; Galloway, Jenna L.

    2015-01-01

    The zebrafish Danio rerio is a powerful model for the study of development, regenerative biology, and human disease. However, the analysis of load-bearing tissues such as tendons and ligaments has been limited in this system. This is largely due to technical limitations that preclude accurate measurement of their mechanical properties. Here, we present a custom tensile testing system that applies nano-Newton scale forces to zebrafish tendons as small as 1 mm in length. Tendon properties were remarkably similar to mammalian tendons, including stress-strain nonlinearity and a linear modulus (515±152 MPa) that aligned closely with mammalian data. Additionally, a simple exponential constitutive law used to describe tendon mechanics was successfully fit to zebrafish tendons; the associated material constants agreed with literature values for mammalian tendons. Finally, mature and aged zebrafish comparisons revealed a significant decline in mechanical function with age. Based on the exponential constitutive model, age related changes were primarily caused by a reduction in nonlinearity (e.g. changes in collagen crimp or fiber recruitment). These findings demonstrate the utility of zebrafish as a model to study tendon biomechanics in health and disease. Moreover, these findings suggest that tendon mechanical behavior is highly conserved across vertebrates. PMID:25665155

  3. Tendon reflex is suppressed during whole-body vibration.

    PubMed

    Karacan, Ilhan; Cidem, Muharrem; Yilmaz, Gizem; Sebik, Oguz; Cakar, Halil Ibrahim; Türker, Kemal Sıtkı

    2016-10-01

    In this study we have investigated the effect of whole body vibration (WBV) on the tendon reflex (T-reflex) amplitude. Fifteen young adult healthy volunteer males were included in this study. Records of surface EMG of the right soleus muscle and accelerometer taped onto the right Achilles tendon were obtained while participant stood upright with the knees in extension, on the vibration platform. Tendon reflex was elicited before and during WBV. Subjects completed a set of WBV. Each WBV set consisted of six vibration sessions using different frequencies (25, 30, 35, 40, 45, 50Hz) applied randomly. In each WBV session the Achilles tendon was tapped five times with a custom-made reflex hammer. The mean peak-to-peak (PP) amplitude of T-reflex was 1139.11±498.99µV before vibration. It decreased significantly during WBV (p<0.0001). The maximum PP amplitude of T-reflex was 1333±515μV before vibration. It decreased significantly during WBV (p<0.0001). No significant differences were obtained in the mean acceleration values of Achilles tendon with tapping between before and during vibration sessions. This study showed that T-reflex is suppressed during WBV. T-reflex suppression indicates that the spindle primary afferents must have been pre-synaptically inhibited during WBV similar to the findings in high frequency tendon vibration studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. A passive exoskeleton with artificial tendons: design and experimental evaluation.

    PubMed

    van Dijk, Wietse; van der Kooij, Herman; Hekman, Edsko

    2011-01-01

    We developed a passive exoskeleton that was designed to minimize joint work during walking. The exoskeleton makes use of passive structures, called artificial tendons, acting in parallel with the leg. Artificial tendons are elastic elements that are able to store and redistribute energy over the human leg joints. The elastic characteristics of the tendons have been optimized to minimize the mechanical work of the human leg joints. In simulation the maximal reduction was 40 percent. The performance of the exoskeleton was evaluated in an experiment in which nine subjects participated. Energy expenditure and muscle activation were measured during three conditions: Normal walking, walking with the exoskeleton without artificial tendons, and walking with the exoskeleton with the artificial tendons. Normal walking was the most energy efficient. While walking with the exoskeleton, the artificial tendons only resulted in a negligibly small decrease in energy expenditure. © 2011 IEEE

  5. The role of bone sialoprotein in the tendon-bone insertion.

    PubMed

    Marinovich, Ryan; Soenjaya, Yohannes; Wallace, Gregory Q; Zuskov, Andre; Dunkman, Andrew; Foster, Brian L; Ao, Min; Bartman, Kevin; Lam, Vida; Rizkalla, Amin; Beier, Frank; Somerman, Martha J; Holdsworth, David W; Soslowsky, Louis J; Lagugné-Labarthet, François; Goldberg, Harvey A

    2016-01-01

    Tendons/ligaments insert into bone via a transitional structure, the enthesis, which is susceptible to injury and difficult to repair. Fibrocartilaginous entheses contain fibrocartilage in their transitional zone, part of which is mineralized. Mineral-associated proteins within this zone have not been adequately characterized. Members of the Small Integrin Binding Ligand N-linked Glycoprotein (SIBLING) family are acidic phosphoproteins expressed in mineralized tissues. Here we show that two SIBLING proteins, bone sialoprotein (BSP) and osteopontin (OPN), are present in the mouse enthesis. Histological analyses indicate that the calcified zone of the quadriceps tendon enthesis is longer in Bsp(-/-) mice, however no difference is apparent in the supraspinatus tendon enthesis. In an analysis of mineral content within the calcified zone, micro-CT and Raman spectroscopy reveal that the mineral content in the calcified fibrocartilage of the quadriceps tendon enthesis are similar between wild type and Bsp(-/-) mice. Mechanical testing of the patellar tendon shows that while the tendons fail under similar loads, the Bsp(-/-) patellar tendon is 7.5% larger in cross sectional area than wild type tendons, resulting in a 16.5% reduction in failure stress. However, Picrosirius Red staining shows no difference in collagen organization. Data collected here indicate that BSP is present in the calcified fibrocartilage of murine entheses and suggest that BSP plays a regulatory role in this structure, influencing the growth of the calcified fibrocartilage in addition to the weakening of the tendon mechanical properties. Based on the phenotype of the Bsp(-/-) mouse enthesis, and the known in vitro functional properties of the protein, BSP may be a useful therapeutic molecule in the reattachment of tendons and ligaments to bone. Copyright © 2016 International Society of Matrix Biology. All rights reserved.

  6. The Role of Bone Sialoprotein in the Tendon-Bone Insertion

    PubMed Central

    Marinovich, Ryan; Soenjaya, Yohannes; Wallace, Gregory Q.; Zuskov, Andre; Dunkman, Andrew; Foster, Brian L.; Ao, Min; Bartman, Kevin; Lam, Vida; Rizkalla, Amin; Beier, Frank; Somerman, Martha J.; Holdsworth, David W.; Soslowsky, Louis J.; Lagugné-Labarthet, François; Goldberg, Harvey A.

    2016-01-01

    Tendons/ligaments insert into bone via a transitional structure, the enthesis, which is susceptible to injury and difficult to repair. Fibrocartilaginous entheses contain fibrocartilage in their transitional zone, part of which is mineralized. Mineral-associated proteins within this zone have not been adequately characterized. Members of the Small Integrin Binding Ligand N-Linked Glycoprotein (SIBLING) family are acidic phosphoproteins expressed in mineralized tissues. Here we show that two SIBLING proteins, bone sialoprotein (BSP) and osteopontin (OPN), are present in the mouse enthesis. Histological analyses indicate that the calcified zone of the quadriceps tendon enthesis is longer in Bsp−/− mice, however no difference is apparent in the supraspinatus tendon enthesis. In an analysis of mineral content within the calcified zone, micro-CT and Raman spectroscopy reveal that the mineral content in the calcified fibrocartilage of the quadriceps tendon enthesis are similar between wild type and Bsp−/− mice. Mechanical testing of the patellar tendon shows that while the tendons fail under similar loads, the Bsp−/− patellar tendon is 7.5% larger in cross sectional area than wild type tendons, resulting in a 16.5% reduction in failure stress. However, picrosirius red staining shows no difference in collagen organization. Data collected here indicate that BSP is present in the calcified fibrocartilage of murine entheses and suggest that BSP plays a regulatory role in this structure, influencing the growth of the calcified fibrocartilage in addition to the weakening of the tendon mechanical properties. Based on the phenotype of the Bsp−/− mouse enthesis, and the known in vitro functional properties of the protein, BSP may be a useful therapeutic molecule in the reattachment of tendons and ligaments to bone. PMID:26826499

  7. The Role of Mechanical Loading in Tendon Development, Maintenance, Injury, and Repair

    PubMed Central

    Galloway, Marc T.; Lalley, Andrea L.; Shearn, Jason T.

    2013-01-01

    Tendon injuries often result from excessive or insufficient mechanical loading, impairing the ability of the local tendon cell population to maintain normal tendon function. ➤ The resident cell population composing tendon tissue is mechanosensitive, given that the cells are able to alter the extracellular matrix in response to modifications of the local loading environment. ➤ Natural tendon healing is insufficient, characterized by improper collagen fibril diameter formation, collagen fibril distribution, and overall fibril misalignment. ➤ Current tendon repair rehabilitation protocols focus on implementing early, well-controlled eccentric loading exercises to improve repair outcome. ➤ Tissue engineers look toward incorporating mechanical loading regimens to precondition cell populations for the creation of improved biological augmentations for tendon repair. PMID:24005204

  8. Temporal changes in sarcomere lesions of rat adductor longus muscles during hindlimb reloading

    NASA Technical Reports Server (NTRS)

    Krippendorf, B. B.; Riley, D. A.

    1994-01-01

    Focal sarcomere disruptions were previously observed in adductor longus muscles of rats flown approximately two weeks aboard the Cosmos 1887 and 2044 biosatellite flights. These lesions, characterized by breakage and loss of myofilaments and Z-line streaming, resembled damage induced by unaccustomed exercise that includes eccentric contractions in which muscles lengthen as they develop tension. We hypothesized that sarcomere lesions in atrophied muscles of space flow rats were not produced in microgravity by muscle unloading but resulted from muscle reloading upon re-exposure to terrestrial gravity. To test this hypothesis, we examined temporal changes in sarcomere integrity of adductor longus muscles from rats subjected to 12.5 days of hindlimb suspension unloading and subsequent reloading by return to vivarium cages for 0, 6, 12, or 48 hours of normal weightbearing. Our ultrastructural observations suggested that muscle unloading (0 h reloading) induced myofibril misalignment associated with myofiber atrophy. Muscle reloading for 6 hours induced focal sarcomere lesions in which cross striations were abnormally widened. Such lesions were electron lucent due to extensive myofilament loss. Lesions in reloaded muscles showed rapid restructuring. By 12 hours of reloading, lesions were moderately stained foci and by 48 hours darkly stained foci in which the pattern of cross striations was indistinct at the light and electron microscopic levels. These lesions were spanned by Z-line-like electron dense filamentous material. Our findings suggest a new role for Z-line streaming in lesion restructuring: rather than an antecedent to damage, this type of Z-line streaming may be indicative of rapid, early sarcomere repair.

  9. Achilles tendon injury risk factors associated with running.

    PubMed

    Lorimer, Anna V; Hume, Patria A

    2014-10-01

    Research into the nature of overuse Achilles tendon injuries is extensive, yet uncertainty remains around how to identify athletes susceptible to Achilles tendon injury. To identify the strength of evidence for biomechanical risk factors associated with Achilles tendon injuries. SPORTDiscus, CINAHL, Web of Science and PubMed were searched for Achilles tendon injury risk factors and biomechanical measures which are altered in runners with Achilles tendon injuries, excluding ruptures. Fifteen articles were included in the analysis. Two variables, high vertical forces and high arch, showed strong evidence for reduced injury risk. High propulsive forces and running on stiffer surfaces may also be protective. Only one biomechanical variable, high braking force, showed clear evidence for increasing Achilles injury risk. Gait retraining to direct the centre of mass further forward to reduce high braking force could be useful in decreasing the risk of Achilles injury. The majority of biomechanical risk factors examined showed unclear results, which is likely due to the multifactorial nature of Achilles overuse injuries. Many risk factors are related to how the athlete's body interacts with the environment during gait, including ground reaction forces, muscle activity both prior to landing and immediately post ground contact, and joint motion throughout stance. Multiple risk factors have been associated with the development of Achilles tendon injuries in running athletes but most effects remain unclear. Advice for athletes recovering from Achilles tendon injuries could include avoiding soft surfaces and reducing the pace of recovery runs. Orthotic intervention could assist athletes with low arches but modification of pronation should be viewed with caution. Strength training and gait retraining could be beneficial for reducing injury risk.

  10. Incidence and clinical outcomes of tendon rupture following distal radius fracture.

    PubMed

    White, Brian D; Nydick, Jason A; Karsky, Dawnne; Williams, Bailee D; Hess, Alfred V; Stone, Jeffrey D

    2012-10-01

    To evaluate the incidence of tendon rupture after nonoperative and operative management of distal radius fractures, report clinical outcomes after tendon repair or transfer, and examine volar plate and dorsal screw prominence as a predictor of tendon rupture. We performed a retrospective chart review on patients treated for tendon rupture after distal radius fracture. We evaluated active range of motion, Disabilities of Arm, Shoulder, and Hand score, grip strength, and pain score, and performed radiographic evaluation of volar plate and dorsal screw prominence in both the study group and a matched control group. There were 6 tendon ruptures in 1,359 patients (0.4%) treated nonoperatively and 8 tendon ruptures in 999 patients (0.8%) treated with volar plate fixation. At the time of final follow-up, regardless of treatment, we noted that patients had minimal pain and excellent motion and grip strength. Mean Disabilities of the Shoulder, Arm, and Hand scores were 6 for patients treated nonoperatively and 4 for those treated with volar plating. We were unable to verify volar plate or dorsal screw prominence as independent risk factors for tendon rupture after distal radius fractures. However, we recommend continued follow-up and plate removal for symptomatic patients who have volar plate prominence or dorsal screw prominence. In the event of tendon rupture, we report excellent clinical outcomes after tendon repair or tendon transfer. Therapeutic IV. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  11. Enhanced tendon-to-bone repair through adhesive films.

    PubMed

    Linderman, Stephen W; Golman, Mikhail; Gardner, Thomas R; Birman, Victor; Levine, William N; Genin, Guy M; Thomopoulos, Stavros

    2018-04-01

    Tendon-to-bone surgical repairs have unacceptably high failure rates, possibly due to their inability to recreate the load transfer mechanisms of the native enthesis. Instead of distributing load across a wide attachment footprint area, surgical repairs concentrate shear stress on a small number of suture anchor points. This motivates development of technologies that distribute shear stresses away from suture anchors and across the enthesis footprint. Here, we present predictions and proof-of-concept experiments showing that mechanically-optimized adhesive films can mimic the natural load transfer mechanisms of the healthy attachment and increase the load tolerance of a repair. Mechanical optimization, based upon a shear lag model corroborated by a finite element analysis, revealed that adhesives with relatively high strength and low stiffness can, theoretically, strengthen tendon-to-bone repairs by over 10-fold. Lap shear testing using tendon and bone planks validated the mechanical models for a range of adhesive stiffnesses and strengths. Ex vivo human supraspinatus repairs of cadaveric tissues using multipartite adhesives showed substantial increase in strength. Results suggest that adhesive-enhanced repair can improve repair strength, and motivate a search for optimal adhesives. Current surgical techniques for tendon-to-bone repair have unacceptably high failure rates, indicating that the initial repair strength is insufficient to prevent gapping or rupture. In the rotator cuff, repair techniques apply compression over the repair interface to achieve contact healing between tendon and bone, but transfer almost all force in shear across only a few points where sutures puncture the tendon. Therefore, we evaluated the ability of an adhesive film, implanted between tendon and bone, to enhance repair strength and minimize the likelihood of rupture. Mechanical models demonstrated that optimally designed adhesives would improve repair strength by over 10-fold

  12. Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats

    PubMed Central

    Cury, Diego Pulzatto; Dias, Fernando José; Miglino, Maria Angélica; Watanabe, Ii-sei

    2016-01-01

    Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis. PMID:27078690

  13. Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats.

    PubMed

    Cury, Diego Pulzatto; Dias, Fernando José; Miglino, Maria Angélica; Watanabe, Ii-sei

    2016-01-01

    Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis.

  14. Current Concepts in Examination and Treatment of Elbow Tendon Injury

    PubMed Central

    Ellenbecker, Todd S.; Nirschl, Robert; Renstrom, Per

    2013-01-01

    Context: Injuries to the tendons of the elbow occur frequently in the overhead athlete, creating a significant loss of function and dilemma to sports medicine professionals. A detailed review of the anatomy, etiology, and pathophysiology of tendon injury coupled with comprehensive evaluation and treatment information is needed for clinicians to optimally design treatment programs for rehabilitation and prevention. Evidence Acquisitions: The PubMed database was searched in January 2012 for English-language articles pertaining to elbow tendon injury. Results: Detailed information on tendon pathophysiology was found along with incidence of elbow injury in overhead athletes. Several evidence-based reviews were identified, providing a thorough review of the recommended rehabilitation for elbow tendon injury. Conclusions: Humeral epicondylitis is an extra-articular tendon injury that is common in athletes subjected to repetitive upper extremity loading. Research is limited on the identification of treatment modalities that can reduce pain and restore function to the elbow. Eccentric exercise has been studied in several investigations and, when coupled with a complete upper extremity strengthening program, can produce positive results in patients with elbow tendon injury. Further research is needed in high-level study to delineate optimal treatment methods. PMID:24427389

  15. Modified rerouting procedure for failed peroneal tendon dislocation surgery.

    PubMed

    Gaulke, R; Hildebrand, F; Panzica, M; Hüfner, T; Krettek, C

    2010-04-01

    Recurrent dislocation of the peroneal tendons following operative treatment is relatively uncommon, but can be difficult to treat. We asked whether subligamental transposition of the peroneus brevis tendon, fibular grooving, and reattachment of the superior peroneal retinaculum for failed peroneal tendon dislocation surgery would achieve a stable fixation of the peroneal tendons and whether there would be restrictions of ROM or instability of the hindfoot. We reviewed six female patients (mean age, 24.5 years) with general laxity of joints preoperatively and at 6 weeks and 3, 6, and 12 months postoperatively. Within 1 year postoperatively no recurrence was found. In two ankles the extension was restricted 5 degrees to 10 degrees . In another pronation and supination was restricted 5 degrees each. Stability of the ankle increased in four patients and stayed unchanged in two. AOFAS score increased from a mean value of 36 +/- 20.6 preoperatively to 90 +/- 7 postoperatively at 1 year. We conclude transposition of the peroneus brevis tendon is a reasonable treatment for failed peroneal tendon dislocation surgery. Level IV, therapeutic study (prospective case series). See Guidelines for Authors for a complete description of levels of evidence.

  16. A wrist tendon travel assessment of hand movements associated with industrial repetitive activities.

    PubMed

    Ugbolue, U Chris; Nicol, Alexander C

    2012-01-01

    To investigate slow and fast paced industrial activity hand repetitive movements associated with carpal tunnel syndrome where movements are evaluated based on finger and wrist tendon travel measurements. Nine healthy subjects were recruited for the study aged between 23 and 33 years. Participants mimicked an industrial repetitive task by performing the following activities: wrist flexion and extension task, palm open and close task; and pinch task. Each task was performed for a period of 5 minutes at a slow (0.33 Hz) and fast (1 Hz) pace for a duration of 3 minutes and 2 minutes respectively. Tendon displacement produced higher flexor digitorum superficialis (FDS) tendon travel when compared to the flexor digitorum profundus (FDP) tendons. The left hand mean (SD) tendon travel for the FDS tendon and FDP tendon were 11108 (5188) mm and 9244 (4328) mm while the right hand mean tendon travel (SD) for the FDS tendon and FDP tendon were 9225 (3441) mm and 7670 (2856) mm respectively. Of the three tasks mimicking an industrial repetitive activity, the wrist flexion and extension task produced the most tendon travel. The findings may be useful to researchers in classifying the level of strenuous activity in relation to tendon travel.

  17. Clinical Outcomes and Return to Sports in Patients with Chronic Achilles Tendon Rupture after Minimally Invasive Reconstruction with Semitendinosus Tendon Graft Transfer.

    PubMed

    Usuelli, Federico Giuseppe; D'Ambrosi, Riccardo; Manzi, Luigi; Indino, Cristian; Villafañe, Jorge Hugo; Berjano, Pedro

    2017-12-01

    Objective  The purpose of the study is to evaluate the clinical results and return to sports in patients undergoing reconstruction of the Achilles tendon after minimally invasive reconstruction with semitendinosus tendon graft transfer. Methods  Eight patients underwent surgical reconstruction with a minimally invasive technique and tendon graft augmentation with ipsilateral semitendinosus tendon for chronic Achilles tendon rupture (more than 30 days after the injury and a gap of >6 cm). Patients were evaluated at a minimum follow-up of 24 months after the surgery through the American Orthopaedic Foot and Ankle Society (AOFAS), the Achilles Tendon Total Rupture Scores (ATRS), the Endurance test, the calf circumference of the operated limb, and the contralateral and the eventual return to sports activity performed before the trauma. Results  The mean age at surgery was 50.5 years. Five men and three women underwent the surgery. The average AOFAS was 92, mean Endurance test was 28.1, and the average ATRS was 87. All patients returned to their daily activities, and six out of eight patients have returned to sports activities prior to the accident (two football players, three runners, one tennis player) at a mean of 7.0 (range: 6.7-7.2) months after the surgery. No patient reported complications or reruptures. Conclusion  Our study confirms encouraging results for the treatment of Achilles tendon rupture with a minimally invasive technique with semitendinosus graft augmentation. The technique can be considered safe and allows patients to return to their sports activity. Level of Evidence  Level IV, therapeutic case series.

  18. Spontaneous tendon rupture in systemic lupus erythematosus: association with Jaccoud's arthropathy.

    PubMed

    Alves, E M; Macieira, J C; Borba, E; Chiuchetta, F A; Santiago, M B

    2010-03-01

    Tendon rupture has rarely been described in patients with systemic lupus erythematosus. From observation of three cases of Jaccoud's arthropathy with tendon rupture, and considering that this arthropathy is more related to an inflammatory process of the tendon sheath than to synovitis per se, the intention of this study was to review the cases of tendon rupture in patients with systemic lupus erythematosus, in the hope of determining the frequency of Jaccoud's arthropathy associated with this complication. Systematic review using MEDLINE, Scielo and LILACS databases (1966 to 2009) and the following keywords: systemic lupus erythematosus, tendon rupture, Jaccoud's arthropathy. Secondary references were additionally obtained. Additionally, three Brazilian systemic lupus erythematosus patients who developed tendon rupture are described. Only 40 articles obtained fulfilled the previously established criteria. They were all case reports; the number of cases reported was 52 which, together with the three cases presented herein add up to 55 cases. Forty-six patients were women aged between 19 and 71 years, with a mean age of 40.1 +/- 12.4 years, and the average duration of the disease was 10 years. The most frequently observed rupture sites were the patellar and Achilles' tendons. While almost all patients described were on various doses of corticosteroids, 16 patients concomitantly had Jaccoud's arthropathy (29%). In conclusion, the association between Jaccoud's arthropathy and tendon rupture in systemic lupus erythematosus has been underestimated. As almost one-third of the systemic lupus erythematosus patients with tendon rupture also have Jaccoud's arthropathy, this arthropathy may be recognized as risk marker for tendon rupture.

  19. Tendon length and joint flexibility are related to running economy.

    PubMed

    Hunter, Gary R; Katsoulis, Konstantina; McCarthy, John P; Ogard, William K; Bamman, Marcas M; Wood, David S; Den Hollander, Jan A; Blaudeau, Tamilane E; Newcomer, Bradley R

    2011-08-01

    The purpose of study was to determine whether quadriceps/patella and Achilles tendon length and flexibility of the knee extensors and plantar flexors are related to walking and running economy. Twenty-one male distance runners were subjects. Quadriceps/patella and Achilles tendon length were measured by magnetic resonance imaging; body composition was measured DXA; oxygen uptake at rest while seated, walking (3 mph), and running (6 and 7 mph) were measured by indirect calorimetry; knee and ankle joint flexibility were measured by goniometry; and leg lengths were measured by anthropometry while seated. Correlations were used to identify relationships between variables of interest. Net VO2 (exercise VO2 - rest VO2) for walking (NVOWK) and running at 6 and 7 mph (NVO6 and NVO7, respectively) was significantly related to Achilles tendon length (r varying from -0.40 to -0.51, P all < 0.04). Achilles tendon cross section was not related to walking or running economy. Quadriceps/patella tendon length was significantly related to NVO7 (r = -0.43, P = 0.03) and approached significance for NVO6 (r = -0.36, P = 0.06). Flexibility of the plantar flexors was related to NVO7 (+0.38, P = 0.05). Multiple regression showed that Achilles tendon length was independently related to NVO6 and NVO7 (partial r varying from -0.53 to -0.64, all P < 0.02) independent of lower leg length, upper leg length, quadriceps/patella tendon length, knee extension flexibility, or plantarflexion flexibility. These data support the premise that longer lower limb tendons (especially Achilles tendon) and less flexible lower limb joints are associated with improved running economy.

  20. The paratenon contributes to scleraxis-expressing cells during patellar tendon healing.

    PubMed

    Dyment, Nathaniel A; Liu, Chia-Feng; Kazemi, Namdar; Aschbacher-Smith, Lindsey E; Kenter, Keith; Breidenbach, Andrew P; Shearn, Jason T; Wylie, Christopher; Rowe, David W; Butler, David L

    2013-01-01

    The origin of cells that contribute to tendon healing, specifically extrinsic epitenon/paratenon cells vs. internal tendon fibroblasts, is still debated. The purpose of this study is to determine the location and phenotype of cells that contribute to healing of a central patellar tendon defect injury in the mouse. Normal adult patellar tendon consists of scleraxis-expressing (Scx) tendon fibroblasts situated among aligned collagen fibrils. The tendon body is surrounded by paratenon, which consists of a thin layer of cells that do not express Scx and collagen fibers oriented circumferentially around the tendon. At 3 days following injury, the paratenon thickens as cells within the paratenon proliferate and begin producing tenascin-C and fibromodulin. These cells migrate toward the defect site and express scleraxis and smooth muscle actin alpha by day 7. The thickened paratenon tissue eventually bridges the tendon defect by day 14. Similarly, cells within the periphery of the adjacent tendon struts express these markers and become disorganized. Cells within the defect region show increased expression of fibrillar collagens (Col1a1 and Col3a1) but decreased expression of tenogenic transcription factors (scleraxis and mohawk homeobox) and collagen assembly genes (fibromodulin and decorin). By contrast, early growth response 1 and 2 are upregulated in these tissues along with tenascin-C. These results suggest that paratenon cells, which normally do not express Scx, respond to injury by turning on Scx and assembling matrix to bridge the defect. Future studies are needed to determine the signaling pathways that drive these cells and whether they are capable of producing a functional tendon matrix. Understanding this process may guide tissue engineering strategies in the future by stimulating these cells to improve tendon repair.

  1. Sports hernia repair with adductor tenotomy.

    PubMed

    Harr, J N; Brody, F

    2017-02-01

    Sports hernias, or athletic pubalgia, is common in athletes, and primarily involves injury to the fascia, muscles, and tendons of the inguinal region near their insertion onto the pubic bone. However, management varies widely, and rectus and adductor tenotomies have not been adequately described. The purpose of this manuscript is to demonstrate a suture repair and a rectus and adductor longus tenotomy technique for sports hernias. After magnetic-resonance-imaging confirmation of sports hernias with rectus and adductor tendonitis, 22 patients underwent a suture herniorrhaphy with adductor tenotomy. The procedure is performed through a 4-cm incision, and a fascial release of the rectus abdominis and adductor tenotomy is performed to relieve the opposing vector forces on the pubic bone. All 22 patients returned to their respective sports and regained their ability to perform at a high level, including professional status. No further surgery was required. In athletes with MRI confirmation of rectus and adductor longus injuries, tenotomies along with a herniorraphy may improve outcomes. A suture repair to reinforce the inguinal floor prevents mesh-related complications, especially in young athletes.

  2. Tensile properties of a morphologically split supraspinatus tendon.

    PubMed

    Matsuhashi, Tomoya; Hooke, Alexander W; Zhao, Kristin D; Goto, Akira; Sperling, John W; Steinmann, Scott P; An, Kai-Nan

    2014-07-01

    The supraspinatus tendon consists morphologically of two sub-regions, anterior and posterior. The anterior sub-region is thick and tubular while the posterior is thin and strap-like. The purpose of this study was to compare the structural and mechanical properties of the anterior and posterior sub-regions of the supraspinatus tendon. The supraspinatus tendons from seven human cadaveric shoulders were morphologically divided into the anterior and posterior sub-regions. Length, width, and thickness were measured. A servo-hydraulic testing machine (MTS Systems Corporation, Minneapolis, MN) was used for tensile testing. The maximal load at failure, modulus of elasticity and ultimate tendon stress were calculated. Repeated measures were used for statistical comparisons. The mean anterior tendon cross-sectional area was 47.3 mm(2) and the posterior was 32.1 mm(2) . Failure occurred most often at the insertion site: anterior (5/7) and posterior (6/7). All parameters of the anterior sub-region were significantly greater than those of the posterior sub-region. The moduli of elasticity at the insertion site were 592.4 MPa in the anterior sub-region and 217.7 MPa in the posterior (P = 0.01). The ultimate failure loads were 779.2 N in the anterior sub-region and 335.6 N in the posterior (P = 0.003). The ultimate stresses were 22.1 MPa in the anterior sub-region and 11.6 MPa in the posterior (P = 0.008). We recognized that the anterior and posterior sub-regions of the SSP tendon have significantly different mechanical properties. In a future study, we need to evaluate how best to repair an SSP tendon considering these region-specific properties. Copyright © 2013 Wiley Periodicals, Inc.

  3. Presence of Bacteria in Spontaneous Achilles Tendon Ruptures.

    PubMed

    Rolf, Christer G; Fu, Sai-Chuen; Hopkins, Chelsea; Luan, Ju; Ip, Margaret; Yung, Shu-Hang; Friman, Göran; Qin, Ling; Chan, Kai-Ming

    2017-07-01

    The structural pathology of Achilles tendon (AT) ruptures resembles tendinopathy, but the causes remain unknown. Recently, a number of diseases were found to be attributed to bacterial infections, resulting in low-grade inflammation and progressive matrix disturbance. The authors speculate that spontaneous AT ruptures may also be influenced by the presence of bacteria. Bacteria are present in ruptured ATs but not in healthy tendons. Cross-sectional study; Level of evidence, 3. Patients with spontaneous AT ruptures and patients undergoing anterior cruciate ligament (ACL) reconstruction were recruited for this study. During AT surgical repair, excised tendinopathic tissue was collected, and healthy tendon samples were obtained as controls from hamstring tendon grafts used in ACL reconstruction. Half of every sample was reserved for DNA extraction and the other half for histology. Polymerase chain reaction (PCR) was conducted using 16S rRNA gene universal primers, and the PCR products were sequenced for the identification of bacterial species. A histological examination was performed to compare tendinopathic changes in the case and control samples. Five of 20 AT rupture samples were positive for the presence of bacterial DNA, while none of the 23 hamstring tendon samples were positive. Sterile operating and experimental conditions and tests on samples, controlling for harvesting and processing procedures, ruled out the chance of postoperative bacterial contamination. The species identified predominantly belonged to the Staphylococcus genus. AT rupture samples exhibited histopathological features characteristic of tendinopathy, and most healthy hamstring tendon samples displayed normal tendon features. There were no apparent differences in histopathology between the bacterial DNA-positive and bacterial DNA-negative AT rupture samples. The authors have demonstrated the presence of bacterial DNA in ruptured AT samples. It may suggest the potential involvement of bacteria

  4. Pain level after ACL reconstruction: A comparative study between free quadriceps tendon and hamstring tendons autografts.

    PubMed

    Buescu, Cristian Tudor; Onutu, Adela Hilda; Lucaciu, Dan Osvald; Todor, Adrian

    2017-03-01

    The objective of this study was to compare the pain levels and analgesic consumption after single bundle ACL reconstruction with free quadriceps tendon autograft versus hamstring tendon autograft. A total of 48 patients scheduled for anatomic single-bundle ACL reconstruction were randomized into two groups: the free quadriceps tendon autograft group (24 patients) and the hamstring tendons autograft group (24 patients). A basic multimodal analgesic postoperative program was used for all patients and rescue analgesia was provided with tramadol, at pain scores over 30 on the Visual Analog Scale. The time to the first rescue analgesic, the number of doses of tramadol and pain scores were recorded. The results within the same group were compared with the Wilcoxon signed test. Supplementary analgesic drug administration proved significantly higher in the group of subjects with hamstring grafts, with a median (interquartile range) of 1 (1.3) dose, compared to the group of subjects treated with a quadriceps graft, median = 0.5 (0.1.25) (p = 0.009). A significantly higher number of subjects with a quadriceps graft did not require any supplementary analgesic drug (50%) as compared with subjects with hamstring graft (13%; Z-statistics = 3.01, p = 0.002). The percentage of subjects who required a supplementary analgesic drug was 38% higher in the HT group compared with the FQT group. The use of the free quadriceps tendon autograft for ACL reconstruction leads to less pain and analgesic consumption in the immediate postoperative period compared with the use of hamstrings autograft. Level I Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  5. Temporal response of canine flexor tendon to limb suspension

    PubMed Central

    Thoreson, Andrew R.; Cha, Stephen S.; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C.

    2010-01-01

    Tendon disuse, or stress deprivation, frequently accompanies clinical disorders and treatments, yet the metabolism of tendons subject to stress deprivation has rarely been investigated systematically. The effects of stress deprivation on canine flexor tendon were investigated in this study. One adult canine forepaw was suspended for 21 or 42 days. Control forepaws were collected from dogs that had no intervention on their limbs and paws. The expression of collagen I and III was not significantly altered in the tendons disused for 21 days but was significantly decreased at 42 days (P < 0.03). The expression of collagen II, aggrecan, decorin, and fibronectin was significantly decreased in the tendons in the suspended limbs at 21 days (P < 0.002) and further reduced at 42 days. With stress deprivation, the expression of matrix metalloproteinase 2 (MMP2) was significantly increased (P < 0.004) at 21 and 42 days. The expression of MMP3 was significantly decreased at 21 and 42 days (P < 0.03). The expression of MMP13 was not altered with stress deprivation at 21 and 42 days. The expression of MMP14 was significantly increased at 21 days (P = 0.0015) and returned to the control level at 42 days. Tissue inhibitor of metalloproteinase 1 (TIMP1) expression was decreased after the limbs were suspended for 42 days (P = 0.0043), but not 21 days. However, TIMP2 expression was not significantly different from control at 21 or 42 days. Furthermore, the cross-sectional area of the stress-deprived tendons at 42 days was decreased compared with the control group (P < 0.01). The intervention method in this study did not result in any alteration of stiffness of the tendon. Our study demonstrated that stress deprivation decreases the anabolic process and increases the catabolic process of extracellular matrix in flexor tendon. PMID:20947711

  6. Effects of Increased Loading on In Vivo Tendon Properties: A Systematic Review

    PubMed Central

    WIESINGER, HANS-PETER; KÖSTERS, ALEXANDER; MÜLLER, ERICH; SEYNNES, OLIVIER R.

    2015-01-01

    ABSTRACT Introduction In vivo measurements have been used in the past two decades to investigate the effects of increased loading on tendon properties, yet the current understanding of tendon macroscopic changes to training is rather fragmented, limited to reports of tendon stiffening, supported by changes in material properties and/or tendon hypertrophy. The main aim of this review was to analyze the existing literature to gain further insights into tendon adaptations by extracting patterns of dose-response and time-course. Methods PubMed/Medline, SPORTDiscus, and Google Scholar databases were searched for studies examining the effect of training on material, mechanical, and morphological properties via longitudinal or cross-sectional designs. Results Thirty-five of 6440 peer-reviewed articles met the inclusion criteria. The key findings were i) the confirmation of a nearly systematic adaptation of tendon tissue to training, ii) the important variability in the observed changes in tendon properties between and within studies, and iii) the absence of a consistent incremental pattern regarding the dose-response or the time-course relation of tendon adaptation within the first months of training. However, long-term (years) training was associated with a larger tendon cross-sectional area, without any evidence of differences in material properties. Our analysis also highlighted several gaps in the existing literature, which may be addressed in future research. Conclusions In line with some cross-species observations about tendon design, tendon cross-sectional area allegedly constitutes the ultimate adjusting parameter to increased loading. We propose here a theoretical model placing tendon hypertrophy and adjustments in material properties as parts of the same adaptive continuum. PMID:25563908

  7. Triple Achilles Tendon Rupture: Case Report.

    PubMed

    Saxena, Amol; Hofer, Deann

    We present a case report with 1-year follow-up data of a 57-year-old male soccer referee who had sustained an acute triple Achilles tendon rupture injury during a game. His triple Achilles tendon rupture consisted of a rupture of the proximal watershed region, a rupture of the main body (mid-watershed area), and an avulsion-type rupture of insertional calcific tendinosis. The patient was treated surgically with primary repair of the tendon, including tenodesis with anchors. Postoperative treatment included non-weightbearing for 4 weeks and protected weightbearing until 10 weeks postoperative, followed by formal physical therapy, which incorporated an "antigravity" treadmill. The patient was able to return to full activity after 26 weeks, including running and refereeing, without limitations. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Muscular activity and torque of the foot dorsiflexor muscles during decremental isometric test: A cross-sectional study.

    PubMed

    Ruiz-Muñoz, Maria; González-Sánchez, Manuel; Martín-Martín, Jaime; Cuesta-Vargas, Antonio I

    2017-06-01

    To analyse the torque variation level that could be explained by the muscle activation (EMG) amplitude of the three major foot dorsiflexor muscles (tibialis anterior (TA), extensor digitorum longus (EDL), extensor hallucis longus (EHL)) during isometric foot dorsiflexion at different intensities. In a cross-sectional study, forty-one subjects performed foot dorsiflexion at 100%, 75%, 50% and 25% of maximal voluntary contractions (MVC) with the hip and knee flexed 90° and the ankle in neutral position (90° between leg and foot). Three foot dorsiflexions were performed for each intensity. Outcome variables were: maximum (100% MVC) and relative torque (75%, 50%, 25% MVC), maximum and relative EMG amplitude. A linear regression analysis was calculated for each intensity of the isometric foot dorsiflexion. The degree of torque variation (dependent variable) from the independent variables explain (EMG amplitude of the three major foot dorsiflexor muscles) the increases when the foot dorsiflexion intensity is increased, with values of R 2 that range from 0.194 (during 25% MVC) to 0.753 (during 100% MVC). The reliability of the outcome variables was excellent. The EMG amplitude of the three main foot dorsiflexors exhibited more variance in the dependent variable (torque) when foot dorsiflexion intensity increases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Eccentric contractions disrupt FKBP12 content in mouse skeletal muscle

    PubMed Central

    Baumann, Cory W.; Rogers, Russell G.; Gahlot, Nidhi; Ingalls, Christopher P.

    2014-01-01

    Abstract Strength deficits associated with eccentric contraction‐induced muscle injury stem, in part, from impaired voltage‐gated sarcoplasmic reticulum (SR) Ca2+ release. FKBP12 is a 12‐kD immunophilin known to bind to the SR Ca2+ release channel (ryanodine receptor, RyR1) and plays an important role in excitation‐contraction coupling. To assess the effects of eccentric contractions on FKBP12 content, we measured anterior crural muscle (tibialis anterior [TA], extensor digitorum longus [EDL], extensor hallucis longus muscles) strength and FKBP12 content in pellet and supernatant fractions after centrifugation via immunoblotting from mice before and after a single bout of either 150 eccentric or concentric contractions. There were no changes in peak isometric torque or FKBP12 content in TA muscles after concentric contractions. However, FKBP12 content was reduced in the pelleted fraction immediately after eccentric contractions, and increased in the soluble protein fraction 3 day after injury induction. FKBP12 content was correlated (P = 0.025; R2= 0.38) to strength deficits immediately after injury induction. In summary, eccentric contraction‐induced muscle injury is associated with significant alterations in FKBP12 content after injury, and is correlated with changes in peak isometric torque. PMID:25347864

  10. Ultrasound elasticity imaging of human posterior tibial tendon

    NASA Astrophysics Data System (ADS)

    Gao, Liang

    Posterior tibial tendon dysfunction (PTTD) is a common degenerative condition leading to a severe impairment of gait. There is currently no effective method to determine whether a patient with advanced PTTD would benefit from several months of bracing and physical therapy or ultimately require surgery. Tendon degeneration is closely associated with irreversible degradation of its collagen structure, leading to changes to its mechanical properties. If these properties could be monitored in vivo, it could be used to quantify the severity of tendonosis and help determine the appropriate treatment. Ultrasound elasticity imaging (UEI) is a real-time, noninvasive technique to objectively measure mechanical properties in soft tissue. It consists of acquiring a sequence of ultrasound frames and applying speckle tracking to estimate displacement and strain at each pixel. The goals of my dissertation were to 1) use acoustic simulations to investigate the performance of UEI during tendon deformation with different geometries; 2) develop and validate UEI as a potentially noninvasive technique for quantifying tendon mechanical properties in human cadaver experiments; 3) design a platform for UEI to measure mechanical properties of the PTT in vivo and determine whether there are detectable and quantifiable differences between healthy and diseased tendons. First, ultrasound simulations of tendon deformation were performed using an acoustic modeling program. The effects of different tendon geometries (cylinder and curved cylinder) on the performance of UEI were investigated. Modeling results indicated that UEI accurately estimated the strain in the cylinder geometry, but underestimated in the curved cylinder. The simulation also predicted that the out-of-the-plane motion of the PTT would cause a non-uniform strain pattern within incompressible homogeneous isotropic material. However, to average within a small region of interest determined by principal component analysis (PCA

  11. Treatment of peroneal nerve injuries with simultaneous tendon transfer and nerve exploration.

    PubMed

    Ho, Bryant; Khan, Zubair; Switaj, Paul J; Ochenjele, George; Fuchs, Daniel; Dahl, William; Cederna, Paul; Kung, Theodore A; Kadakia, Anish R

    2014-08-06

    Common peroneal nerve palsy leading to foot drop is difficult to manage and has historically been treated with extended bracing with expectant waiting for return of nerve function. Peroneal nerve exploration has traditionally been avoided except in cases of known traumatic or iatrogenic injury, with tendon transfers being performed in a delayed fashion after exhausting conservative treatment. We present a new strategy for management of foot drop with nerve exploration and concomitant tendon transfer. We retrospectively reviewed a series of 12 patients with peroneal nerve palsies that were treated with tendon transfer from 2005 to 2011. Of these patients, seven were treated with simultaneous peroneal nerve exploration and repair at the time of tendon transfer. Patients with both nerve repair and tendon transfer had superior functional results with active dorsiflexion in all patients, compared to dorsiflexion in 40% of patients treated with tendon transfers alone. Additionally, 57% of patients treated with nerve repair and tendon transfer were able to achieve enough function to return to running, compared to 20% in patients with tendon transfer alone. No patient had full return of native motor function resulting in excessive dorsiflexion strength. The results of our limited case series for this rare condition indicate that simultaneous nerve repair and tendon transfer showed no detrimental results and may provide improved function over tendon transfer alone.

  12. Decorin expression is important for age-related changes in tendon structure and mechanical properties

    PubMed Central

    Dunkman, Andrew A.; Buckley, Mark R.; Mienaltowski, Michael J.; Adams, Sheila M.; Thomas, Stephen J.; Satchell, Lauren; Kumar, Akash; Pathmanathan, Lydia; Beason, David P.; Iozzo, Renato V.; Birk, David E.; Soslowsky, Louis J.

    2013-01-01

    The aging population is at an increased risk of tendon injury and tendinopathy. Elucidating the molecular basis of tendon aging is crucial to understanding the age-related changes in structure and function in this vulnerable tissue. In this study, the structural and functional features of tendon aging are investigated. In addition, the roles of decorin and biglycan in the aging process were analyzed using transgenic mice at both mature and aged time points. Our hypothesis is that the increase in tendon injuries in the aging population is the result of altered structural properties that reduce the biomechanical function of the tendon and consequently increase susceptibility to injury. Decorin and biglycan are important regulators of tendon structure and therefore, we further hypothesized that decreased function in aged tendons is partly the result of altered decorin and biglycan expression. Biomechanical analyses of mature (day 150) and aged (day 570) patellar tendons revealed deteriorating viscoelastic properties with age. Histology and polarized light microscopy demonstrated decreased cellularity, alterations in tenocyte shape, and reduced collagen fiber alignment in the aged tendons. Ultrastructural analysis of fibril diameter distributions indicated an altered distribution in aged tendons with an increase of large diameter fibrils. Aged wild type tendons maintained expression of decorin which was associated with the structural and functional changes seen in aged tendons. Aged patellar tendons exhibited altered and generally inferior properties across multiple assays. However, decorin-null tendons exhibited significantly decreased effects of aging compared to the other genotypes. The amelioration of the functional deficits seen in the absence of decorin in aged tendons was associated with altered tendon fibril structure. Fibril diameter distributions in the decorin-null aged tendons were comparable to those observed in the mature wild type tendon with the absence

  13. [Application of silk-based tissue engineering scaffold for tendon / ligament regeneration].

    PubMed

    Hu, Yejun; Le, Huihui; Jin, Zhangchu; Chen, Xiao; Yin, Zi; Shen, Weiliang; Ouyang, Hongwei

    2016-03-01

    Tendon/ligament injury is one of the most common impairments in sports medicine. The traditional treatments of damaged tissue repair are unsatisfactory, especially for athletes, due to lack of donor and immune rejection. The strategy of tissue engineering may break through these limitations, and bring new hopes to tendon/ligament repair, even regeneration. Silk is a kind of natural biomaterials, which has good biocompatibility, wide range of mechanical properties and tunable physical structures; so it could be applied as tendon/ligament tissue engineering scaffolds. The silk-based scaffold has robust mechanical properties; combined with other biological ingredients, it could increase the surface area, promote more cell adhesion and improve the biocompatibility. The potential clinical application of silk-based scaffold has been confirmed by in vivo studies on tendon/ligament repairing, such as anterior cruciate ligament, medial collateral ligament, achilles tendon and rotator cuff. To develop novel biomechanically stable and host integrated tissue engineered tendon/ligament needs more further micro and macro studies, combined with product development and clinical application, which will give new hope to patients with tendon/ligament injury.

  14. Arthroscopically Assisted Latissimus Dorsi Tendon Transfer in Beach-Chair Position

    PubMed Central

    Jermolajevas, Viktoras; Kordasiewicz, Bartlomiej

    2015-01-01

    Irreparable rotator cuff tears remain a surgical problem. The open technique of latissimus dorsi (LD) tendon transfer to “replace” the irreparable rotator cuff is already well known. The aim of this article is to present a modified arthroscopically assisted LD tendon transfer technique. This technique was adopted to operate on patients in the beach-chair position with several improvements in tendon harvesting and fixation. It can be divided into 6 steps, and only 1 step—LD muscle and tendon release—is performed open. The advantages of the arthroscopic procedure are sparing of the deltoid muscle, the possibility of repairing the subscapularis tendon, and the ability to visualize structures at risk while performing tendon harvesting (radial nerve) and passing into the subacromial space (axillary nerve). It is performed in a similar manner to standard rotator cuff surgery—the beach-chair position does not need any modification, and no sophisticated equipment for either the open or arthroscopic part of the procedure is necessary. Nevertheless, this is a challenging procedure and should only be attempted after training, as well as extensive practice. PMID:26759777

  15. No Telescoping Effect with Dual Tendon Vibration.

    PubMed

    Bellan, Valeria; Wallwork, Sarah B; Stanton, Tasha R; Reverberi, Carlo; Gallace, Alberto; Moseley, G Lorimer

    2016-01-01

    The tendon vibration illusion has been extensively used to manipulate the perceived position of one's own body part. However, findings from previous research do not seem conclusive sregarding the perceptual effect of the concurrent stimulation of both agonist and antagonist tendons over one joint. On the basis of recent data, it has been suggested that this paired stimulation generates an inconsistent signal about the limb position, which leads to a perceived shrinkage of the limb. However, this interesting effect has never been replicated. The aim of the present study was to clarify the effect of a simultaneous and equal vibration of the biceps and triceps tendons on the perceived location of the hand. Experiment 1 replicated and extended the previous findings. We compared a dual tendon stimulation condition with single tendon stimulation conditions and with a control condition (no vibration) on both 'upward-downward' and 'towards-away from the elbow' planes. Our results show a mislocalisation towards the elbow of the position of the vibrated arm during dual vibration, in line with previous results; however, this did not clarify whether the effect was due to arm representation contraction (i.e., a 'telescoping' effect). Therefore, in Experiment 2 we investigated explicitly and implicitly the perceived arm length during the same conditions. Our results clearly suggest that in all the vibration conditions there was a mislocalisation of the entire arm (including the elbow), but no evidence of a contraction of the perceived arm length.

  16. Marked innervation but also signs of nerve degeneration in between the Achilles and plantaris tendons and presence of innervation within the plantaris tendon in midportion Achilles tendinopathy

    PubMed Central

    Spang, C.; Harandi, V.M.; Alfredson, H.; Forsgren, S.

    2015-01-01

    Objectives: The plantaris tendon is increasingly recognised as an important factor in midportion Achilles tendinopathy. Its innervation pattern is completely unknown. Methods: Plantaris tendons (n=56) and associated peritendinous tissue from 46 patients with midportion Achilles tendinopathy and where the plantaris tendon was closely related to the Achilles tendon were evaluated. Morphological evaluations and stainings for nerve markers [general (PGP9.5), sensory (CGRP), sympathetic (TH)], glutamate NMDA receptor and Schwann cells (S-100β) were made. Results: A marked innervation, as evidenced by evaluation for PGP9.5 reactions, occurred in the peritendinous tissue located between the plantaris and Achilles tendons. It contained sensory and to some extent sympathetic and NMDAR1-positive axons. There was also an innervation in the zones of connective tissue within the plantaris tendons. Interestingly, some of the nerve fascicles showed a partial lack of axonal reactions. Conclusion: New information on the innervation patterns for the plantaris tendon in situations with midportion Achilles tendinopathy has here been obtained. The peritendinous tissue was found to be markedly innervated and there was also innervation within the plantaris tendon. Furthermore, axonal degeneration is likely to occur. Both features should be further taken into account when considering the relationship between the nervous system and tendinopathy. PMID:26032213

  17. Exposure of a tendon extracellular matrix to synovial fluid triggers endogenous and engrafted cell death: A mechanism for failed healing of intrathecal tendon injuries.

    PubMed

    Garvican, Elaine R; Salavati, Mazdak; Smith, Roger K W; Dudhia, Jayesh

    2017-09-01

    The purpose of this study was to investigate the effect of normal synovial fluid (SF) on exposed endogenous tendon-derived cells (TDCs) and engrafted mesenchymal stem cells (MSCs) within the tendon extracellular matrix. Explants from equine superficial digital flexor (extra-synovial) and deep digital flexor tendons (DDFTs) from the compressed, intra-synovial and the tensile, extra-synovial regions were cultured in allogeneic or autologous SF-media. Human hamstring explants were cultured in allogeneic SF. Explant viability was assessed by staining. Proliferation of equine monolayer MSCs and TDCs in SF-media and co-culture with DDFT explants was determined by alamarblue®. Non-viable Native Tendon matrices (NNTs) were re-populated with MSCs or TDCs and cultured in SF-media. Immunohistochemical staining of tendon sections for the apoptotic proteins caspase-3, -8, and -9 was performed. Contact with autologous or allogeneic SF resulted in rapid death of resident tenocytes in equine and human tendon. SF did not affect the viability of equine epitenon cells, or of MSCs and TDCs in the monolayer or indirect explant co-culture. MSCs and TDCs, engrafted into NNTs, died when cultured in SF. Caspase-3, -8, and -9 expression was the greatest in SDFT explants exposed to allogeneic SF. The efficacy of cells administered intra-synovially for tendon lesion repair is likely to be limited, since once incorporated into the matrix, cells become vlnerable to the adverse effects of SF. These observations could account for the poor success rate of intra-synovial tendon healing following damage to the epitenon and contact with SF, common with most soft tissue intra-synovial pathologies.

  18. Plyometric Training Favors Optimizing Muscle–Tendon Behavior during Depth Jumping

    PubMed Central

    Hirayama, Kuniaki; Iwanuma, Soichiro; Ikeda, Naoki; Yoshikawa, Ayumi; Ema, Ryoichi; Kawakami, Yasuo

    2017-01-01

    The purpose of the present study was to elucidate how plyometric training improves stretch–shortening cycle (SSC) exercise performance in terms of muscle strength, tendon stiffness, and muscle–tendon behavior during SSC exercise. Eleven men were assigned to a training group and ten to a control group. Subjects in the training group performed depth jumps (DJ) using only the ankle joint for 12 weeks. Before and after the period, we observed reaction forces at foot, muscle–tendon behavior of the gastrocnemius, and electromyographic activities of the triceps surae and tibialis anterior during DJ. Maximal static plantar flexion strength and Achilles tendon stiffness were also determined. In the training group, maximal strength remained unchanged while tendon stiffness increased. The force impulse of DJ increased, with a shorter contact time and larger reaction force over the latter half of braking and initial half of propulsion phases. In the latter half of braking phase, the average electromyographic activity (mEMG) increased in the triceps surae and decreased in tibialis anterior, while fascicle behavior of the gastrocnemius remained unchanged. In the initial half of propulsion, mEMG of triceps surae and shortening velocity of gastrocnemius fascicle decreased, while shortening velocity of the tendon increased. These results suggest that the following mechanisms play an important role in improving SSC exercise performance through plyometric training: (1) optimization of muscle–tendon behavior of the agonists, associated with alteration in the neuromuscular activity during SSC exercise and increase in tendon stiffness and (2) decrease in the neuromuscular activity of antagonists during a counter movement. PMID:28179885

  19. Real-time sonoelastography as novel follow-up method in Achilles tendon surgery.

    PubMed

    Busilacchi, A; Olivieri, M; Ulisse, S; Gesuita, R; Skrami, E; Lording, T; Fusini, F; Gigante, A

    2016-07-01

    To evaluate the sonoelastographic features of Achilles tendon healing after percutaneous treatment using real-time sonoelastography, a new tool able to quantify deformation in biological tissues. Patients with atraumatic Achilles tendon ruptures, treated with a percutaneous technique, were assessed. Sonoelastographic evaluations were performed at the myotendinous junction, tendon body/lesion site and osteotendinous junction, both for the operated and contralateral side, at 40 days, 6 months and 1 year after surgery. Using standard regions of interest, the "strain index" (SI) was calculated as an indicator of tendon elasticity. Clinical outcomes were assessed by the ATRS questionnaire at 6 months and 1 year post-operatively and correlated with sonoelastographic findings. Sixty healthy tendons from 30 volunteers were used to provide a healthy control range. Twenty-five patients were recruited for this study. The SI in treated tendons showed progressive stiffening over time, especially at myotendinous junction and at the site of the sutured lesion, resulting in significantly higher stiffness than both the contralateral tendon and healthy volunteers. Peak thickness of treated tendons occurred at 6 months, with a tendency to reduce at 1 year, while never achieving a normal physiological state. Greatest remodelling was seen at the lesion site. The contralateral tendon showed significant thickening at the myotendinous and osteotendinous junctions. The SI of the contralateral tendon was found to be stiffer than physiological values found in the control group. ATRS score improved significantly between 6 months and 1 year, being negatively correlated with the SI (p < 0.001). RTSE showed that operatively treated Achilles tendons become progressively stiffer during follow-up, while the ATRS score improved. From a biomechanical point of view, at 1 year after surgery Achilles tendons did not show a "restitutio ad integrum". Real-time sonoelastography provides more

  20. Peroneal tendon pathology: Pre- and post-operative high resolution US and MR imaging.

    PubMed

    Kumar, Yogesh; Alian, Ali; Ahlawat, Shivani; Wukich, Dane K; Chhabra, Avneesh

    2017-07-01

    Peroneal tendon pathology is an important cause of lateral ankle pain and instability. Typical peroneal tendon disorders include tendinitis, tenosynovitis, partial and full thickness tendon tears, peroneal retinacular injuries, and tendon subluxations and dislocations. Surgery is usually indicated when conservative treatment fails. Familiarity with the peroneal tendon surgeries and expected postoperative imaging findings is essential for accurate assessment and to avoid diagnostic pitfalls. Cross-sectional imaging, especially ultrasound and MRI provide accurate pre-operative and post-operative evaluation of the peroneal tendon pathology. In this review article, the normal anatomy, clinical presentation, imaging features, pitfalls and commonly performed surgical treatments for peroneal tendon abnormalities will be reviewed. The role of dynamic ultrasound and kinematic MRI for the evaluation of peroneal tendons will be discussed. Normal and abnormal postsurgical imaging appearances will be illustrated. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Pentadecapeptide BPC 157 enhances the growth hormone receptor expression in tendon fibroblasts.

    PubMed

    Chang, Chung-Hsun; Tsai, Wen-Chung; Hsu, Ya-Hui; Pang, Jong-Hwei Su

    2014-11-19

    BPC 157, a pentadecapeptide derived from human gastric juice, has been demonstrated to promote the healing of different tissues, including skin, muscle, bone, ligament and tendon in many animal studies. However, the underlying mechanism has not been fully clarified. The present study aimed to explore the effect of BPC 157 on tendon fibroblasts isolated from Achilles tendon of male Sprague-Dawley rat. From the result of cDNA microarray analysis, growth hormone receptor was revealed as one of the most abundantly up-regulated genes in tendon fibroblasts by BPC 157. BPC 157 dose- and time-dependently increased the expression of growth hormone receptor in tendon fibroblasts at both the mRNA and protein levels as measured by RT/real-time PCR and Western blot, respectively. The addition of growth hormone to BPC 157-treated tendon fibroblasts dose- and time-dependently increased the cell proliferation as determined by MTT assay and PCNA expression by RT/real-time PCR. Janus kinase 2, the downstream signal pathway of growth hormone receptor, was activated time-dependently by stimulating the BPC 157-treated tendon fibroblasts with growth hormone. In conclusion, the BPC 157-induced increase of growth hormone receptor in tendon fibroblasts may potentiate the proliferation-promoting effect of growth hormone and contribute to the healing of tendon.

  2. Effects of Trypsinization and Mineralization on Intrasynovial Tendon Allograft Healing to Bone

    PubMed Central

    Qu, Jin; van Alphen, Nick A.; Thoreson, Andrew R.; Chen, Qingshan; An, Kai-Nan; Amadio, Peter C.; Schmid, Thomas M.; Zhao, Chunfeng

    2014-01-01

    The purpose of the current study was to develop a novel technology to enhance tendon-to-bone interface healing by trypsinizing and mineralizing (TM) an intrasynovial tendon allograft in a rabbit bone tunnel model. Eight rabbit flexor digitorum profundus (FDP) tendons were used to optimize the trypsinization process. An additional 24 FDP tendons were stratified into control and TM groups; in each group, 4 tendons were used for in vitro evaluation of TM and 8 were transplanted into proximal tibial bone tunnels in rabbits. The samples were evaluated histologically and with mechanical testing at postoperative week 8. Maximum failure strength and linear stiffness were not significantly different between the control and TM tendons. A thin fibrous band of scar tissue formed at the graft-to-bone interface in the control group. However, only the TM group showed obvious new bone formation inside the tendon graft and a visible fibrocartilage layer at the bone tunnel entrance. This study is the first to explore effects of TM on the intrasynovial allograft healing to a bone tunnel. TM showed beneficial effects on chondrogenesis, osteogenesis, and integration of the intrasynovial tendon graft, but mechanical strength was the same as the control tendons in this short-term in vivo study. PMID:25611186

  3. Effects of sodium hyaluronate on tendon healing and adhesion formation in horses.

    PubMed

    Gaughan, E M; Nixon, A J; Krook, L P; Yeager, A E; Mann, K A; Mohammed, H; Bartel, D L

    1991-05-01

    Sodium hyaluronate reduces adhesions after tendon repair in rodents and dogs, and has been used in limited clinical trials in people. To evaluate its effect on tendon healing and adhesion formation in horses and to compare these effects with those of a compound of similar visco-elastic properties, a study was performed in horses, using a model of collagenase injection in the flexor tendons within the digital sheath. Eight clinically normal horses were randomly allotted to 2 groups. Adhesion formation between the deep digital flexor tendon and the tendon sheath at the pastern region was induced in the forelimbs of all horses. Using tenoscopic control, a 20-gauge needle was inserted into the deep digital flexor tendon of horses under general anesthesia and 0.2 ml of collagenase (2.5 mg/ml) was injected. The procedure was repeated proximally at 2 other sites, spaced 1.5 cm apart. A biopsy forceps was introduced, and a 5-mm tendon defect was created at each injection site. Group-A horses had 120 mg of sodium hyaluronate (NaHA) gel injected into the tendon sheath of one limb. Group-B horses had methylcellulose gel injected at the same sites. The contralateral limbs of horses in both groups served as surgical, but noninjected, controls. Horses were euthanatized after 8 weeks of stall rest. Ultrasonographic evaluation revealed improved tendon healing after NaHa injection, but no difference in peritendinous adhesion formation. Tendon sheath fluid volume and hyaluronic acid (HA) content were greater in NaHA-treated limbs. Gross pathologic examination revealed considerably fewer and smaller adhesions when limbs were treated with NaHA. However, significant difference in pull-out strengths was not evident between NaHA-treated and control limbs. Histologically, the deep digital flexor tendon from the NaHA-treated limbs had reduced inflammatory cell infiltration, improved tendon structure, and less intratendinous hemorrhage. Treatment with methylcullulose had no significant

  4. Is tibialis anterior tendon transfer effective for recurrent clubfoot?

    PubMed

    Gray, Kelly; Burns, Joshua; Little, David; Bellemore, Michael; Gibbons, Paul

    2014-02-01

    Tibialis anterior tendon transfer surgery forms a part of Ponseti management for children with congenital talipes equinovarus who, after initial correction, present with residual dynamic supination. Although retrospective studies support good outcomes, prospective longitudinal studies in this population are lacking. We assessed strength, plantar loading, ROM, foot alignment, function, satisfaction, and quality of life in patients with clubfoot that recurred after Ponseti casting who met indications for tibialis anterior tendon transfer surgery, and compared them with a group of patients with clubfoot treated with casting but whose deformity did not recur (therefore who were not indicated for tibialis anterior tendon transfer surgery). Twenty children with idiopathic congenital talipes equinovarus indicated for tibialis anterior tendon transfer surgery were recruited. Assessment at baseline (before surgery), and 3, 6, and 12 months (after surgery) included strength (hand-held dynamometry), plantar loading (capacitance transducer matrix platform), ROM (Dimeglio scale), foot alignment (Foot Posture Index(©)), function and satisfaction (disease-specific instrument for clubfoot), and quality of life (Infant Toddler Quality of Life Questionnaire™). Outcomes were compared with those of 12 age-matched children with congenital talipes equinovarus not indicated for tibialis anterior tendon transfer surgery. Followup was 100% in the control group and 95% (19 of 20) in the tibialis anterior transfer group. At baseline, the tibialis anterior tendon transfer group had a significantly worse eversion-to-inversion strength ratio, plantar loading, ROM, foot alignment, and function and satisfaction. At 3 months after surgery, eversion-to-inversion strength, plantar loading, and function and satisfaction were no longer different between groups. Improvements were maintained at 12 months after surgery (eversion-to-inversion strength mean difference, 8% body weight; 95% CI, -26% to 11

  5. Effects of foot orthoses on Achilles tendon load in recreational runners.

    PubMed

    Sinclair, J; Isherwood, J; Taylor, P J

    2014-09-01

    Achilles tendon pathology is a frequently occurring musculoskeletal disorder in runners. Foot orthoses have been shown to reduce the symptoms of pain in runners but their mechanical effects are still not well understood. This study aimed to examine differences in Achilles tendon load when running with and without orthotic intervention. Twelve male runners ran at 4.0 m·s(-1). Ankle joint moments and Achilles tendon forces were compared when running with and without orthotics. The results indicate that running with foot orthotics was associated with significant reductions in Achilles tendon load compared to without orthotics. In addition to providing insight into the mechanical effects of orthotics in runners, the current investigation suggests that via reductions in Achilles tendon load, foot orthoses may serve to reduce the incidence of chronic Achilles tendon pathologies in runners. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Reconstruction of Ligament and Tendon Defects Using Cell Technologies.

    PubMed

    Chailakhyan, R K; Shekhter, A B; Ivannikov, S V; Tel'pukhov, V I; Suslin, D S; Gerasimov, Yu V; Tonenkov, A M; Grosheva, A G; Panyushkin, P V; Moskvina, I L; Vorob'eva, N N; Bagratashvili, V N

    2017-02-01

    We studied the possibility of restoring the integrity of the Achilles tendon in rabbits using autologous multipotent stromal cells. Collagen or gelatin sponges populated with cells were placed in a resorbable Vicryl mesh tube and this tissue-engineered construct was introduced into a defect of the middle part of the Achilles tendon. In 4 months, histological analysis showed complete regeneration of the tendon with the formation of parallel collagen fibers, spindle-shaped tenocytes, and newly formed vessels.

  7. Persistence of deep-tendon reflexes during partial cataplexy.

    PubMed

    Barateau, Lucie; Pizza, Fabio; Lopez, Régis; Antelmi, Elena; Plazzi, Giuseppe; Dauvilliers, Yves

    2018-05-01

    Deep-tendon reflexes are abolished during generalized cataplexy, but whether this is the case in partial cataplexy currently remains unknown. Partial cataplexy may mimic other neurologic/psychiatric phenomena, and knowledge of the reflexes status may provide information for differential diagnosis. We assessed whether deep-tendon reflexes are persistent during partial cataplexy. Five drug-free patients with typical diagnoses of narcolepsy and clear-cut partial cataplexy were diagnosed in Reference Narcolepsy Centers in France and Italy. Biceps and patellar reflexes were elicited by physicians in charge and video-documented during cataplexy. Reflexes were assessed several times for each patient in different conditions and for various localizations of cataplexy. The absence of tendon reflexes and complete loss of muscle tone during generalized cataplexy was confirmed, but the persistence of those reflexes during several partial cataplectic attacks at different ages, gender, localization of cataplexy (upper limbs, face) and reflexes (biceps, patellar) in drug-naive or withdrawal conditions was documented. The persistence of tendon reflexes during several partial cataplexy episodes contrasts with their absence during generalized cataplexy. This discovery has clinical implications: the persistence of tendon reflexes does not rule out cataplexy diagnosis for partial attacks, whereas their transient abolishment or persistence during generalized attacks indicates cataplexy or pseudocataplexy, respectively. Copyright © 2018. Published by Elsevier B.V.

  8. Rotator Cuff Repair with a Tendon-Fibrocartilage-Bone Composite Bridging Patch

    PubMed Central

    Ji, Xiaoxi; Chen, Qingshan; Thoreson, Andrew R.; Qu, Jin; An, Kai-Nan; Amadio, Peter C.; Steinmann, Scott P.; Zhao, Chunfeng

    2015-01-01

    Background To compare the mechanical performance of a rotator cuff repaired with a novel tendon-fibrocartilage-bone composite bridging patch vs the traditional Mason-Allen repair in an in vitro canine model. Methods Twenty shoulders and 10 bridging patches from patellar tendon were harvested. The patches were trimmed and sliced into 2 layers. An infraspinatus tendon tear was created in each shoulder. Modified Mason-Allen sutures were used to repair the infraspinatus tendon to the greater tuberosity, with or without the bridging patch (bridging patch group and controls, respectively). Shoulders were loaded to failure under displacement control at a rate of 0.5mm/sec. Findings The ultimate tensile load was significantly higher in the bridging patch group than control (mean [SD], 365.46 [36.45] vs 272.79 [48.88] N; P<.001). Stiffness at the greater tuberosity repair site and the patch-infraspinatus tendon repair site was significantly higher than the control repair site (93.96 [27.72] vs 42.62 [17.48] N/mm P<.001; 65.94 [24.51] vs 42.62 [17.48] N/mm P=.02, respectively). Interpretation The tendon-fibrocartilage-bone composite bridging patch achieved higher ultimate tensile load and stiffness at the patch–greater tuberosity repair site compared with traditional repair in a canine model. This composite tissue transforms the traditional tendon-to-bone healing interface (with dissimilar tissues) into a pair of bone-to-bone and tendon-to-tendon interfaces, which may improve healing quality and reduce retear rate. PMID:26190097

  9. Rotator cuff repair with a tendon-fibrocartilage-bone composite bridging patch.

    PubMed

    Ji, Xiaoxi; Chen, Qingshan; Thoreson, Andrew R; Qu, Jin; An, Kai-Nan; Amadio, Peter C; Steinmann, Scott P; Zhao, Chunfeng

    2015-11-01

    To compare the mechanical performance of a rotator cuff repaired with a novel tendon-fibrocartilage-bone composite bridging patch vs the traditional Mason-Allen repair in an in vitro canine model. Twenty shoulders and 10 bridging patches from patellar tendon were harvested. The patches were trimmed and sliced into 2 layers. An infraspinatus tendon tear was created in each shoulder. Modified Mason-Allen sutures were used to repair the infraspinatus tendon to the greater tuberosity, with or without the bridging patch (bridging patch group and controls, respectively). Shoulders were loaded to failure under displacement control at a rate of 0.5mm/s. The ultimate tensile load was significantly higher in the bridging patch group than control (mean [SD], 365.46 [36.45] vs 272.79 [48.88] N; P<.001). Stiffness at the greater tuberosity repair site and the patch-infraspinatus tendon repair site was significantly higher than the control repair site (93.96 [27.72] vs 42.62 [17.48] N/mm P<.001; 65.94 [24.51] vs 42.62 [17.48] N/mm P=.02, respectively). The tendon-fibrocartilage-bone composite bridging patch achieved higher ultimate tensile load and stiffness at the patch-greater tuberosity repair site compared with traditional repair in a canine model. This composite tissue transforms the traditional tendon-to-bone healing interface (with dissimilar tissues) into a pair of bone-to-bone and tendon-to-tendon interfaces, which may improve healing quality and reduce retear rate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. The Location-Specific Role of Proteoglycans in the Flexor Carpi Ulnaris Tendon

    PubMed Central

    Buckley, Mark R.; Huffman, George R.; Iozzo, Renato V.; Birk, David E.; Soslowsky, Louis J.

    2015-01-01

    Tendons like the flexor carpi ulnaris (FCU) that contain region-specific distributions of proteoglycans (PGs) as a result of the heterogeneous, multi-axial loads they are subjected to in vivo provide valuable models for understanding structure-function relationships in connective tissues. However, the contributions of specific PGs to FCU tendon mechanical properties are unknown. Therefore, the objective of this study was to determine how the location-dependent, viscoelastic mechanical properties of the FCU tendon are impacted individually by PG-associated glycosaminoglycans (GAGs) and by two small leucine-rich proteoglycans (SLRPs), biglycan and decorin. Full length FCU tendons from biglycan- and decorin-null mice were compared to wild type mice to evaluate the effects of specific SLRPs, while chondroitinase ABC digestion of isolated specimens removed from the tendon midsubstance was used to determine how chontroitin/dermatan sulfate (CS/DS) GAGs impact mechanics in mature FCU tendons. A novel combined genetic knockout/ digestion technique also was employed to compare SLRP-null and wild-type tendons in the absence of CS/DS GAGs that may impact properties in the mature state. In all genotypes, mechanical properties in the FCU tendon midsubstance were not affected by GAG digestion. Full-length tendons exhibited complex, multi-axial deformation under tension that may be associated with their in vivo loading environment. Mechanical properties were adversely affected by the absence of biglycan, and a decreased modulus localized in the center of the tendon was measured. These results help elucidate the role that local alterations in proteoglycan levels may play in processes that adversely impact tendon functionality including injury and pathology. PMID:23941206

  11. Palmaris Longus Muscle's Prevalence in Different Nations and Interesting Anatomical Variations: Review of the Literature.

    PubMed

    Ioannis, Dimitriou; Anastasios, Katsourakis; Konstantinos, Natsis; Lazaros, Kostretzis; Georgios, Noussios

    2015-11-01

    The prevalence of the palmaris longus (PL) muscle varies more than any other muscle in the human body. Its absence across the world ranges between 1.5% and 63.9%. It presents with many different anomalies, discovered either clinically, intraoperatively or after anatomical examination of cadavers. This paper includes recent studies and reports about the presence and variations of the PL muscle, thereby illustrating the differences between ethnic groups, as well as emphasizing the different ways of finding it, during daily clinical and surgical practice.

  12. Whole-body vibration training induces hypertrophy of the human patellar tendon.

    PubMed

    Rieder, F; Wiesinger, H-P; Kösters, A; Müller, E; Seynnes, O R

    2016-08-01

    Animal studies suggest that regular exposure to whole-body vibration (WBV) induces an anabolic response in bone and tendon. However, the effects of this type of intervention on human tendon properties and its influence on the muscle-tendon unit function have never been investigated. The aim of this study was to investigate the effect of WBV training on the patellar tendon mechanical, material and morphological properties, the quadriceps muscle architecture and the knee extension torque-angle relationship. Fifty-five subjects were randomized into either a vibration, an active control, or an inactive control group. The active control subjects performed isometric squats on a vibration platform without vibration. Muscle and tendon properties were measured using ultrasonography and dynamometry. Vibration training induced an increase in proximal (6.3%) and mean (3.8%) tendon cross-sectional area, without any appreciable change in tendon stiffness and modulus or in muscle architectural parameters. Isometric torque at a knee angle of 90° increased in active controls (6.7%) only and the torque-angle relation remained globally unchanged in all groups. The present protocol did not appreciably alter knee extension torque production or the musculo-tendinous parameters underpinning this function. Nonetheless, this study shows for the first time that WBV elicits tendon hypertrophy in humans. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Supraspinatus tendinosis associated with biceps brachii tendon displacement in a dog.

    PubMed

    Fransson, Boel A; Gavin, Patrick R; Lahmers, Kevin K

    2005-11-01

    A 4-year-old spayed female Australian Cattle Dog (Blue Heeler) was evaluated because of right forelimb lameness of 5 months' duration. Orthopedic evaluation revealed signs of pain localized to the cranial aspects of both shoulder joints. Via magnetic resonance imaging, the mass of the supraspinatus tendon insertion in both shoulder joints was increased, compared with findings in cadavers of clinically normal dogs; additional imaging procedures revealed that, compared with clinically normal tendons, the tendon had increased signal intensity that was consistent with increased fluid content. The increased supraspinatus tendon mass in each shoulder joint was associated with medial displacement of the biceps brachii tendon, which was more severe in the right limb. Arthroscopic evaluations of both shoulder joints revealed no abnormalities. The dog underwent surgery, and the abnormal parts of the tendons were resected. The most prominent finding on histologic examination of excised tissues was severe myxomatous degeneration. The lameness resolved, and at 22 months after surgery, the dog was reported to have had no recurrence of lameness. The clinical signs and histologic appearance of the tendons in this dog strongly resemble findings associated with tendinosis in humans. Decompression of the biceps brachii tendon may have contributed to the successful outcome after surgery in this dog. Supraspinatus tendinosis should be considered among the differential diagnoses in dogs with uni- or bilateral forelimb lameness.

  14. Infrapatellar fat pad disruption: a radiographic sign of patellar tendon rupture.

    PubMed

    Chin, Kingsley R; Sodl, Jeffrey F

    2005-11-01

    After knee trauma, radiographs showing patella alta supercede other signs that suggest patellar tendon rupture. However, without patella alta the diagnosis may be missed. A standard lateral radiograph with the knee flexed showed the infrapatellar fat pad as a dark band with a smooth contour. Our pilot study identified a disruption of the fat pad contour as a radiographic sign of tendon rupture. Two blinded reviewers independently analyzed randomly selected lateral radiographs of the knees of 14 patients with knee injuries. Seven patients had confirmed ruptures diagnosed at surgery, and the other patients had different diagnoses. There were 12 men and two women with an average age of 49 years (range, 20-81 years). One observer detected five of the seven disrupted tendons and six of the seven intact tendons. The other observer detected six of the seven disrupted tendons and all seven intact tendons. Disruption in the contour of the infrapatellar fat pad on routine lateral view radiographs was a reasonably reliable sign of patellar tendon rupture. Diagnostic accuracy should increase when used with the patient's history, physical examination, and other radiographic signs. Absence of this sign should not supersede other suggestive signs of patella tendon rupture. Diagnostic study, Level II (development of diagnostic criteria on consecutive patients--with universally applied reference "gold" standard). See the Guidelines for Authors for a complete description of levels of evidence.

  15. Analysis of achilles tendon vascularity with second-generation contrast-enhanced ultrasound.

    PubMed

    Genovese, Eugenio; Ronga, Mario; Recaldini, Chiara; Fontana, Federico; Callegari, Leonardo; Maffulli, Nicola; Fugazzola, Carlo

    2011-01-01

    To compare morphological, power Doppler, and contrast-enhanced ultrasound (CEUS) features of the Achilles tendon between asymptomatic athletes and athletes who had undergone surgical repair of a previous rupture. Twenty-four athletes were divided in two groups (A and B). Group A included 14 patients with a median age of 32 years (range 27 to 47 years) who had undergone surgical repair for unilateral Achilles tendon rupture. Group B (control group) included 10 subjects with a median age of 34 years (range 27 to 40 years) with no previous or present history of tendinopathy. All patients were evaluated with ultrasound, power Doppler, and CEUS with second-generation contrast agent. We studied the uninjured Achilles tendon in athletes of group A and either the left or the right Achilles tendon of the athletes in group B. CEUS showed a significantly greater ability to detect a greater number of vascular spots within the uninjured tendon of group A compared to group B (<0.05). In athletes who had suffered a tear of an Achilles tendon, CEUS detected small vessels that were not identified by power Doppler ultrasound in the uninjured contralateral Achilles tendon. CEUS is useful to evaluate vascularity not detected by other imaging techniques. Vascularity in the uninjured tendon seems to be increased in patients who had a previous rupture. Copyright © 2011 Wiley Periodicals, Inc.

  16. Tissue Engineering Strategies for the Tendon/ligament-to-bone insertion

    PubMed Central

    Smith, Lester; Xia, Younan; Galatz, Leesa M.; Genin, Guy M.; Thomopoulos, Stavros

    2012-01-01

    Injuries to connective tissues are painful and disabling and result in costly medical expenses. These injuries often require re-attachment of an unmineralized connective tissue to bone. The uninjured tendon/ligament-to-bone insertion (enthesis) is a functionally graded material that exhibits a gradual transition from soft tissue (i.e., tendon or ligament) to hard tissue (i.e., mineralized bone) through a fibrocartilaginous transition region. This transition is believed to facilitate force transmission between the two dissimilar tissues by ameliorating potentially damaging interfacial stress concentrations. The transition region is impaired or lost upon tendon/ligament injury and is not regenerated following surgical repair or natural healing, exposing the tissue to risk of re-injury. The need to regenerate a robust tendon-to-bone insertion has led a number of tissue engineering repair strategies. This review treats the tendon-to-bone insertion site as a tissue structure whose primary role is mechanical and discusses current and emerging strategies for engineering the tendon/ligament-to-bone insertion in this context. The focus lies on strategies for producing mechanical structures that can guide and subsequently sustain a graded tissue structure and the associated cell populations. PMID:22185608

  17. Tissue-engineering strategies for the tendon/ligament-to-bone insertion.

    PubMed

    Smith, Lester; Xia, Younan; Galatz, Leesa M; Genin, Guy M; Thomopoulos, Stavros

    2012-01-01

    Injuries to connective tissues are painful and disabling and result in costly medical expenses. These injuries often require reattachment of an unmineralized connective tissue to bone. The uninjured tendon/ligament-to-bone insertion (enthesis) is a functionally graded material that exhibits a gradual transition from soft tissue (i.e., tendon or ligament) to hard tissue (i.e., mineralized bone) through a fibrocartilaginous transition region. This transition is believed to facilitate force transmission between the two dissimilar tissues by ameliorating potentially damaging interfacial stress concentrations. The transition region is impaired or lost upon tendon/ligament injury and is not regenerated following surgical repair or natural healing, exposing the tissue to risk of reinjury. The need to regenerate a robust tendon-to-bone insertion has led a number of tissue engineering repair strategies. This review treats the tendon-to-bone insertion site as a tissue structure whose primary role is mechanical and discusses current and emerging strategies for engineering the tendon/ligament-to-bone insertion in this context. The focus lies on strategies for producing mechanical structures that can guide and subsequently sustain a graded tissue structure and the associated cell populations.

  18. "Superior cleft sign" as a marker of rectus abdominus/adductor longus tear in patients with suspected sportsman's hernia.

    PubMed

    Murphy, Grainne; Foran, Paul; Murphy, Darra; Tobin, Oliver; Moynagh, Michael; Eustace, Stephen

    2013-06-01

    We describe a new imaging sign, the "superior cleft sign", identified at both symphysography and MRI, which should be used as a marker of rectus abdominis/adductor longus attachment tearing. A study population of 25 patients presenting with clinically suspected sportsman's hernia, who had undergone both symphysography and MRI of the groin were included for study. In each case, images were reviewed to determine the presence of a superior cleft, secondary cleft, and or both abnormalities. Images of all patients complaining of groin crease discomfort similar to sportsman's hernia revealed the presence of a superior cleft at the rectus abdominis/adductor longus attachment. This "superior cleft sign" correlated with the side of symptoms in each case, and, in contrast to the previously described secondary cleft along the inferior margin of the inferior pubic ramus, occurred parallel to the inferior margin of the superior pubic ramus. The presence of the "superior cleft sign" should be sought in addition to the previously described secondary cleft sign in sportspeople presenting with exercise-related groin pain or pubalgia. It should specifically be sought in patients referred with suspected sportsman's hernia.

  19. Extracorporeal shock wave treatment for chronic rotator cuff tendonitis (shoulder pain).

    PubMed

    Ho, C

    2007-01-01

    (1) Electrohydraulic, electromagnetic, or piezoelectric devices are used to translate energy into acoustic waves during extracorporeal shock wave treatment (ESWT) for chronic rotator cuff tendonitis (shoulder pain). The acoustic waves may help to accelerate the healing process of chronic rotator cuff tendonitis via an unknown mechanism. (2) ESWT, which is performed as an outpatient procedure, is intended to alleviate the pain due to chronic rotator cuff tendonitis. (3) Limited evidence from a German study indicates that the cost of ESWT for rotator cuff tendonitis is one-fifth to one-seventh the cost of surgical treatment, with longer recovery time and time off work in the surgical treatment group accounting for about two-thirds of the overall cost. (4) The evidence reviewed for this bulletin supports the use of high-energy ESWT for chronic calcific rotator cuff tendonitis, but not for non-calcific rotator cuff tendonitis. High-quality RCTs with larger sample sizes are needed to provide stronger evidence.

  20. Applied Joint-Space Torque and Stiffness Control of Tendon-Driven Fingers

    NASA Technical Reports Server (NTRS)

    Abdallah, Muhammad E.; Platt, Robert, Jr.; Wampler, Charles W.; Hargrave, Brian

    2010-01-01

    Existing tendon-driven fingers have applied force control through independent tension controllers on each tendon, i.e. in the tendon-space. The coupled kinematics of the tendons, however, cause such controllers to exhibit a transient coupling in their response. This problem can be resolved by alternatively framing the controllers in the joint-space of the manipulator. This work presents a joint-space torque control law that demonstrates both a decoupled and significantly faster response than an equivalent tendon-space formulation. The law also demonstrates greater speed and robustness than comparable PI controllers. In addition, a tension distribution algorithm is presented here to allocate forces from the joints to the tendons. It allocates the tensions so that they satisfy both an upper and lower bound, and it does so without requiring linear programming or open-ended iterations. The control law and tension distribution algorithm are implemented on the robotic hand of Robonaut-2.

  1. The V-Shaped Distal Triceps Tendon Repair: A Comparative Biomechanical Analysis.

    PubMed

    Scheiderer, Bastian; Imhoff, Florian B; Morikawa, Daichi; Lacheta, Lucca; Obopilwe, Elifho; Cote, Mark P; Imhoff, Andreas B; Mazzocca, Augustus D; Siebenlist, Sebastian

    2018-05-01

    Restoring footprint anatomy, minimizing gap formation, and maximizing the strength of distal triceps tendon repairs are essential factors for a successful healing process and return to sport. The novel V-shaped distal triceps tendon repair technique with unicortical button fixation closely restores footprint anatomy, provides minimal gap formation and high ultimate failure load, and minimizes iatrogenic fracture risk in acute/subacute distal triceps tendon tears. Controlled laboratory study. Twenty-four cadaveric elbows (mean ± SD age, 66 ± 5 years) were randomly assigned to 1 of 3 repair groups: the transosseous cruciate repair technique (gold standard), the knotless suture-bridge repair technique, and the V-shaped distal triceps tendon repair technique. Anatomic measurements of the central triceps tendon footprint were obtained in all specimens with a 3-dimensional digitizer before and after the repair. Cyclic loading was performed for a total of 1500 cycles at a rate of 0.25 Hz, pulling in the direction of the triceps. Displacements were measured on the medial and lateral tendon sites with 2 differential variable reluctance transducers. Load to failure and construct failure mode were recorded. The mean triceps bony insertion area was 399.05 ± 81.23 mm 2 . The transosseous cruciate repair technique restored 36.6% ± 16.8% of the native tendon insertion area, which was significantly different when compared with the knotless suture-bridge repair technique (85.2% ± 14.8%, P = .001) and the V-shaped distal triceps tendon repair technique (88.9% ± 14.8%, P = .002). Mean displacement showed no significant difference between the V-shaped distal triceps tendon repair technique (medial side, 0.75 ± 0.56 mm; lateral side, 0.99 ± 0.59 mm) and the knotless suture-bridge repair technique (1.61 ± 0.97 mm and 1.29 ± 0.8 mm) but significance between the V-shaped distal triceps tendon repair technique and the transosseous cruciate repair technique (4.91 ± 1.12 mm and 5

  2. Freezing does not alter multiscale tendon mechanics and damage mechanisms in tension.

    PubMed

    Lee, Andrea H; Elliott, Dawn M

    2017-12-01

    It is common in biomechanics to use previously frozen tissues, where it is assumed that the freeze-thaw process does not cause consequential mechanical or structural changes. We have recently quantified multiscale tendon mechanics and damage mechanisms using previously frozen tissue, where damage was defined as an irreversible change in the microstructure that alters the macroscopic mechanical parameters. Because freezing has been shown to alter tendon microstructures, the objective of this study was to determine if freezing alters tendon multiscale mechanics and damage mechanisms. Multiscale testing using a protocol that was designed to evaluate tendon damage (tensile stress-relaxation followed by unloaded recovery) was performed on fresh and previously frozen rat tail tendon fascicles. At both the fascicle and fibril levels, there was no difference between the fresh and frozen groups for any of the parameters, suggesting that there is no effect of freezing on tendon mechanics. After unloading, the microscale fibril strain fully recovered, and interfibrillar sliding only partially recovered, suggesting that the tendon damage is localized to the interfibrillar structures and that mechanisms of damage are the same in both fresh and previously frozen tendons. © 2017 New York Academy of Sciences.

  3. Manipulation of Foot Strike and Footwear Increases Achilles Tendon Loading During Running.

    PubMed

    Rice, Hannah; Patel, Mubarak

    2017-08-01

    The Achilles tendon is the most common site of tendon overuse injury in humans. Running with a forefoot strike pattern and in minimal shoes is a topic of recent interest, yet evidence is currently limited regarding the combined influence of foot strike and footwear on Achilles tendon loading. To investigate the influence of both foot strike and footwear on Achilles tendon loading in habitual rearfoot strike runners. Controlled laboratory study. Synchronized kinematic and force data were collected from 22 habitual rearfoot strikers (11 male), who habitually ran in nonminimal running shoes, during overground running at 3.6 m·s -1 . Participants ran in 3 different footwear conditions (standard running shoe, minimal running shoe, and barefoot) with both a rearfoot strike (RFS) and an imposed forefoot strike (FFS) in each footwear condition. Achilles tendon loading was estimated by use of inverse dynamics, where the Achilles tendon moment arm was determined with a regression equation. A 2-way, repeated-measures analysis of variance was used to compare conditions. Achilles tendon impulse was greater when subjects ran with an FFS rather than an RFS in minimal shoes. Achilles tendon loading rates were higher when subjects ran either in minimal shoes or barefoot than in standard shoes, regardless of foot strike. In runners who habitually rearfoot strike in standard running shoes, running in minimal shoes or barefoot increased the rate of tendon loading, and running with a forefoot strike in minimal shoes increased the magnitude of tendon loading. Transitioning to these running conditions may increase the risk of tendinopathy.

  4. No Telescoping Effect with Dual Tendon Vibration

    PubMed Central

    Bellan, Valeria; Wallwork, Sarah B.; Stanton, Tasha R.; Reverberi, Carlo; Gallace, Alberto; Moseley, G. Lorimer

    2016-01-01

    The tendon vibration illusion has been extensively used to manipulate the perceived position of one’s own body part. However, findings from previous research do not seem conclusive sregarding the perceptual effect of the concurrent stimulation of both agonist and antagonist tendons over one joint. On the basis of recent data, it has been suggested that this paired stimulation generates an inconsistent signal about the limb position, which leads to a perceived shrinkage of the limb. However, this interesting effect has never been replicated. The aim of the present study was to clarify the effect of a simultaneous and equal vibration of the biceps and triceps tendons on the perceived location of the hand. Experiment 1 replicated and extended the previous findings. We compared a dual tendon stimulation condition with single tendon stimulation conditions and with a control condition (no vibration) on both ‘upward-downward’ and ‘towards-away from the elbow’ planes. Our results show a mislocalisation towards the elbow of the position of the vibrated arm during dual vibration, in line with previous results; however, this did not clarify whether the effect was due to arm representation contraction (i.e., a ‘telescoping’ effect). Therefore, in Experiment 2 we investigated explicitly and implicitly the perceived arm length during the same conditions. Our results clearly suggest that in all the vibration conditions there was a mislocalisation of the entire arm (including the elbow), but no evidence of a contraction of the perceived arm length. PMID:27305112

  5. The Coracohumeral Distance in Shoulders With Traumatic and Degenerative Subscapularis Tendon Tears.

    PubMed

    Balke, Maurice; Banerjee, Marc; Greshake, Oliver; Hoeher, Juergen; Bouillon, Bertil; Liem, Dennis

    2016-01-01

    A reduced coracohumeral distance (CHD) is thought to be responsible for subcoracoid impingement. This only accounts for degenerative tendon tears. In traumatic tears, the subcoracoid space should be normal. The CHD in patients with traumatic subscapularis tendon tears is larger than that in patients with degenerative tears and does not differ from patients with an intact subscapularis tendon. Cohort study; Level of evidence, 3. A total of 83 patients with arthroscopically certified subscapularis tendon tears were included in the study. Forty-four patients had degenerative causes (group 1), and 39 had traumatic causes (group 2). The control group consisted of 20 patients with traumatic supraspinatus tendon tears and arthroscopically proven, intact subscapularis tendons (group 3). On preoperative axial magnetic resonance imaging, the distance between the CHD was measured, and the values of the 3 groups were compared using the t test. The mean (±SD) CHD in patients with degenerative subscapularis tendon tears was 8.6 ± 2.0 mm (range, 4.0-13.2 mm) and was significantly (P = .0003) smaller than that in patients with traumatic tears (10.2 ± 2.0 mm; range, 6.6-16.2 mm) or controls (10.4 ± 1.8 mm; range, 6.8-14.0 mm). The CHD of controls and patients with traumatic tears did not differ significantly (P = .7875). A CHD of less than 6 mm only occurred in patients with degenerative subscapularis tendon tears. The hypothesis that the CHD in patients with degenerative subscapularis tendon tears is significantly smaller than that in patients with traumatic tears or intact subscapularis tendons was confirmed. The CHD in patients with traumatic tears does not differ from that in controls. A CHD of less than 6 mm only occurs in patients with degenerative subscapularis tendon tears. © 2015 The Author(s).

  6. Quadriceps tendon autograft for arthroscopic knee ligament reconstruction: use it now, use it often.

    PubMed

    Sheean, Andrew J; Musahl, Volker; Slone, Harris S; Xerogeanes, John W; Milinkovic, Danko; Fink, Christian; Hoser, Christian

    2018-04-28

    Traditional bone-patellar tendon-bone and hamstring tendon ACL grafts are not without limitations. A growing body of anatomic, biomechanical and clinical data has demonstrated the utility of quadriceps tendon autograft in arthroscopic knee ligament reconstruction. The quadriceps tendon autograft provides a robust volume of tissue that can be reliably harvested, mitigating the likelihood of variably sized grafts and obviating the necessity of allograft augmentation. Modern, minimally invasive harvest techniques offer the advantages of low rates of donor site morbidity and residual extensor mechanism strength deficits. New data suggest that quadriceps tendon autograft may possess superior biomechanical characteristics when compared with bone-patella tendon-bone (BPTB) autograft. However, there have been very few direct, prospective comparisons between the clinical outcomes associated with quadriceps tendon autograft and other autograft options (eg, hamstring tendon and bone-patellar tendon-bone). Nevertheless, quadriceps tendon autograft should be one of the primary options in any knee surgeon's armamentarium. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. Accumulation of oxidized LDL in the tendon tissues of C57BL/6 or apolipoprotein E knock-out mice that consume a high fat diet: potential impact on tendon health.

    PubMed

    Grewal, Navdeep; Thornton, Gail M; Behzad, Hayedeh; Sharma, Aishwariya; Lu, Alex; Zhang, Peng; Reid, W Darlene; Granville Alex Scott, David J

    2014-01-01

    Clinical studies have suggested an association between dyslipidemia and tendon injuries or chronic tendon pain; the mechanisms underlying this association are not yet known. The objectives of this study were (1) to evaluate the impact of a high fat diet on the function of load-bearing tendons and on the distribution in tendons of oxidized low density lipoprotein (oxLDL), and (2) to examine the effect of oxLDL on tendon fibroblast proliferation and gene expression. Gene expression (Mmp2, Tgfb1, Col1a1, Col3a1), fat content (Oil Red O staining), oxLDL levels (immunohistochemistry) and tendon biomechanical properties were examined in mice (C57Bl/6 or ApoE -/-) receiving a standard or a high fat diet. Human tendon fibroblast proliferation and gene expression (COL1A1, COL3A1, MMP2) were examined following oxLDL exposure. In both types of mice (C57Bl/6 or ApoE -/-), consumption of a high fat diet led to a marked increase in oxLDL deposition in the load-bearing extracellular matrix of the tendon. The consumption of a high fat diet also reduced the failure stress and load of the patellar tendon in both mouse types, and increased Mmp2 expression. ApoE -/- mice exhibited more pronounced reductions in tendon function than wild-type mice, and decreased expression of Col1a1 compared to wild type mice. Human tendon fibroblasts responded to oxLDL by increasing their proliferation and their mRNA levels of MMP2, while decreasing their mRNA levels for COL1A1 and COL3A1. The consumption of a high fat diet resulted in deleterious changes in tendon function, and these changes may be explained in part by the effects of oxLDL, which induced a proliferative, matrix-degrading phenotype in human tenocytes.

  8. Inflamed shoulder tendons (image)

    MedlinePlus

    Tearing and inflammation of the tendons of the shoulder muscles can occur in sports which require the ... pitching, swimming, and lifting weights. Most often the shoulder will heal if a break is taken from ...

  9. The Influence of External Load on Quadriceps Muscle and Tendon Dynamics during Jumping.

    PubMed

    Earp, Jacob E; Newton, Robert U; Cormie, Prue; Blazevich, Anthony J

    2017-11-01

    Tendons possess both viscous (rate-dependent) and elastic (rate-independent) properties that determine tendon function. During high-speed movements external loading increases both the magnitude (FT) and rate (RFDT) of tendon loading. The influence of external loading on muscle and tendon dynamics during maximal vertical jumping was explored. Ten resistance-trained men performed parallel-depth, countermovement vertical jumps with and without additional load (0%, 30%, 60%, and 90% of maximum squat lift strength), while joint kinetics and kinematics, quadriceps tendon length (LT) and patellar tendon FT and RFDT were estimated using integrated ultrasound, motion analysis and force platform data and muscle tendon modelling. Estimated FT and RFDT, but not peak LT, increased with external loading. Temporal comparisons between 0% and 90% loads revealed that FT was greater with 90% loading throughout the majority of the movement (11%-81% and 87%-95% movement duration). However, RFDT was greater with 90% load only during the early movement initiation phase (8%-15% movement duration) but was greater in the 0% load condition later in the eccentric phase (27%-38% movement duration). LT was longer during the early movement (12%-23% movement duration) but shorter in the late eccentric and early concentric phases (48%-55% movement duration) with 90% load. External loading positively influenced peak FT and RFDT but tendon strain appeared unaffected, suggesting no additive effect of external loading on patellar tendon lengthening during human jumping. Temporal analysis revealed that external loading resulted in a large initial RFDT that may have caused dynamic stiffening of the tendon and attenuated tendon strain throughout the movement. These results suggest that external loading influences tendon lengthening in both a load- and movement-dependent manner.

  10. Triceps tendon tear in a middle-aged weightlifter.

    PubMed

    Molloy, Joseph M; Aberle, Curtis J; Escobar, Eduardo

    2013-11-01

    The patient was a 47-year-old man who was evaluated by a physical therapist for a chief complaint of posterior right elbow pain. The patient routinely participated in weightlifting activities and reported a sudden onset of triceps weakness and posterior elbow pain while performing clap push-ups 3 days prior. A physician assistant ordered radiographs, which were initially interpreted as normal, and routine magnetic resonance imaging for the right elbow. Following examination by a physical therapist, due to concern for a triceps tendon tear, the previously ordered magnetic resonance imaging was expedited, which revealed a partial triceps tendon tear with partial tendon retraction medially.

  11. Cellular and molecular maturation in fetal and adult ovine calcaneal tendons

    PubMed Central

    Russo, Valentina; Mauro, Annunziata; Martelli, Alessandra; Di Giacinto, Oriana; Di Marcantonio, Lisa; Nardinocchi, Delia; Berardinelli, Paolo; Barboni, Barbara

    2015-01-01

    Processes of development during fetal life profoundly transform tendons from a plastic tissue into a highly differentiated structure, characterised by a very low ability to regenerate after injury in adulthood. Sheep tendon is frequently used as a translational model to investigate cell-based regenerative approaches. However, in contrast to other species, analytical and comparative baseline studies on the normal developmental maturation of sheep tendons from fetal through to adult life are not currently available. Thus, a detailed morphological and biochemical study was designed to characterise tissue maturation during mid- (2 months of pregnancy: 14 cm of length) and late fetal (4 months: 40 cm of length) life, through to adulthood. The results confirm that ovine tendon morphology undergoes profound transformations during this period. Endotenon was more developed in fetal tendons than in adult tissues, and its cell phenotype changed through tendon maturation. Indeed, groups of large rounded cells laying on smaller and more compacted ones expressing osteocalcin, vascular endothelial growth factor (VEGF) and nerve growth factor (NGF) were identified exclusively in fetal mid-stage tissues, and not in late fetal or adult tendons. VEGF, NGF as well as blood vessels and nerve fibers showed decreased expression during tendon development. Moreover, the endotenon of mid- and late fetuses contained identifiable cells that expressed several pluripotent stem cell markers [Telomerase Reverse Transcriptase (TERT), SRY Determining Region Y Box-2 (SOX2), Nanog Homeobox (NANOG) and Octamer Binding Transcription Factor-4A (OCT-4A)]. These cells were not identifiable in adult specimens. Ovine tendon development was also accompanied by morphological modifications to cell nuclei, and a progressive decrease in cellularity, proliferation index and expression of connexins 43 and 32. Tendon maturation was similarly characterised by modulation of several other gene expression

  12. Repair of insertional achilles tendinosis with a bone-quadriceps tendon graft.

    PubMed

    Philippot, Rémi; Wegrzyn, Julien; Grosclaude, Sophie; Besse, Jean Luc

    2010-09-01

    While conservative treatment may be successful in most cases, partial rupture at the calcaneal insertion point is a significant concern with insertional Achilles tendinopathy. We report on the outcomes of a surgical technique for Achilles tendon augmentation using a bone-tendon graft harvested from the knee extensor system. Our retrospective case series includes 25 surgical procedures performed in 24 patients, 19 males and five females, with a mean age of 47 (range, 30 to 59) years, 18 of whom were athletes. The mean followup period was 52 (range, 12 to 156) months. All patients underwent MRI examination prior to surgery which showed partial Achilles tendon rupture. The Achilles tendon was debrided through a posterolateral approach. The bone-quadriceps tendon graft was harvested, then the bone plug of the graft was inserted into a blind tunnel drilled into the calcaneus and fixed with an interference screw. The fibers of the quadriceps tendon were sutured to the residual part of the Achilles tendon with the foot at an angle of 90 degrees. Patients were able to resume their sporting activity after an average of 6.7 months. At last followup examination, physical activity was scored 5.2 on the 10-point Tegner Scale; the mean AOFAS score was 98.4. MRI examination showed good graft integration 1 year postoperatively. The bone-quadriceps tendon grafting technique was a good alternative for the insertional Achilles lesions with partial detachment which we felt required augmentation.

  13. Different culture conditions affect the growth of human tendon stem/progenitor cells (TSPCs) within a mixed tendon cells (TCs) population.

    PubMed

    Viganò, M; Perucca Orfei, C; Colombini, A; Stanco, D; Randelli, P; Sansone, V; de Girolamo, L

    2017-12-01

    Tendon resident cells (TCs) are a mixed population made of terminally differentiated tenocytes and tendon stem/progenitor cells (TSPCs). Since the enrichment of progenitors proportion could enhance the effectiveness of treatments based on these cell populations, the interest on the effect of culture conditions on the TSPCs is growing. In this study the clonal selection and the culture in presence or absence of basic fibroblast growth factor (bFGF) were used to assess their influences on the stemness properties and phenotype specific features of tendon cells. Cells cultured with the different methods were analyzed in terms of clonogenic and differentiation abilities, stem and tendon specific genes expression and immunophenotype at passage 2 and passage 4. The clonal selection allowed to isolate cells with a higher multi-differentiation potential, but at the same time a lower proliferation rate in comparison to the whole population. Moreover, the clones express a higher amounts of stemness marker OCT4 and tendon specific transcription factor Scleraxis (SCX) mRNA, but a lower level of decorin (DCN). On the other hand, the number of cells obtained by clonal selection was extremely low and most of the clones were unable to reach a high number of passages in cultures. The presence of bFGF influences TCs morphology, enhance their proliferation rate and reduce their clonogenic ability. Interestingly, the expression of CD54, a known mesenchymal stem cell marker, is reduced in presence of bFGF at early passages. Nevertheless, bFGF does not affect the chondrogenic and osteogenic potential of TCs and the expression of tendon specific markers, while it was able to downregulate the OCT4 expression. This study showed that clonal selection enhance progenitors content in TCs populations, but the extremely low number of cells produced with this method could represent an insurmountable obstacle to its application in clinical approaches. We observed that the addition of bFGF to the

  14. Tendon-to-bone attachment: from development to maturity.

    PubMed

    Zelzer, Elazar; Blitz, Einat; Killian, Megan L; Thomopoulos, Stavros

    2014-03-01

    The attachment between tendon and bone occurs across a complex transitional tissue that minimizes stress concentrations and allows for load transfer between muscles and skeleton. This unique tissue cannot be reconstructed following injury, leading to high incidence of recurrent failure and stressing the need for new clinical approaches. This review describes the current understanding of the development and function of the attachment site between tendon and bone. The embryonic attachment unit, namely, the tip of the tendon and the bone eminence into which it is inserted, was recently shown to develop modularly from a unique population of Sox9- and Scx-positive cells, which are distinct from tendon fibroblasts and chondrocytes. The fate and differentiation of these cells is regulated by transforming growth factor beta and bone morphogenetic protein signaling, respectively. Muscle loads are then necessary for the tissue to mature and mineralize. Mineralization of the attachment unit, which occurs postnatally at most sites, is largely controlled by an Indian hedgehog/parathyroid hormone-related protein feedback loop. A number of fundamental questions regarding the development of this remarkable attachment system require further study. These relate to the signaling mechanism that facilitates the formation of an interface with a gradient of cellular and extracellular phenotypes, as well as to the interactions between tendon and bone at the point of attachment. Copyright © 2014 Wiley Periodicals, Inc.

  15. Changes in tendon spatial frequency parameters with loading.

    PubMed

    Pearson, Stephen J; Engel, Aaron J; Bashford, Gregory R

    2017-05-24

    To examine and compare the loading related changes in micro-morphology of the patellar tendon. Fifteen healthy young males (age 19±3yrs, body mass 83±5kg) were utilised in a within subjects matched pairs design. B mode ultrasound images were taken in the sagittal plane of the patellar tendon at rest with the knee at 90° flexion. Repeat images were taken whilst the subjects were carrying out maximal voluntary isometric contractions. Spatial frequency parameters related to the tendon morphology were determined within regions of interest (ROI) from the B mode images at rest and during isometric contractions. A number of spatial parameters were observed to be significantly different between resting and contracted images (Peak spatial frequency radius (PSFR), axis ratio, spatial Q-factor, PSFR amplitude ratio, and the sum). These spatial frequency parameters were indicative of acute alterations in the tendon micro-morphology with loading. Acute loading modifies the micro-morphology of the tendon, as observed via spatial frequency analysis. Further research is warranted to explore its utility with regard to different loading induced micro-morphological alterations, as these could give valuable insight not only to aid strengthening of this tissue but also optimization of recovery from injury and treatment of conditions such as tendinopathies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Stretching Your Energetic Budget: How Tendon Compliance Affects the Metabolic Cost of Running

    PubMed Central

    Uchida, Thomas K.; Hicks, Jennifer L.; Dembia, Christopher L.; Delp, Scott L.

    2016-01-01

    Muscles attach to bones via tendons that stretch and recoil, affecting muscle force generation and metabolic energy consumption. In this study, we investigated the effect of tendon compliance on the metabolic cost of running using a full-body musculoskeletal model with a detailed model of muscle energetics. We performed muscle-driven simulations of running at 2–5 m/s with tendon force–strain curves that produced between 1 and 10% strain when the muscles were developing maximum isometric force. We computed the average metabolic power consumed by each muscle when running at each speed and with each tendon compliance. Average whole-body metabolic power consumption increased as running speed increased, regardless of tendon compliance, and was lowest at each speed when tendon strain reached 2–3% as muscles were developing maximum isometric force. When running at 2 m/s, the soleus muscle consumed less metabolic power at high tendon compliance because the strain of the tendon allowed the muscle fibers to operate nearly isometrically during stance. In contrast, the medial and lateral gastrocnemii consumed less metabolic power at low tendon compliance because less compliant tendons allowed the muscle fibers to operate closer to their optimal lengths during stance. The software and simulations used in this study are freely available at simtk.org and enable examination of muscle energetics with unprecedented detail. PMID:26930416

  17. [Research progress of cell-scaffold complex in tendon tissue engineering].

    PubMed

    Zhu, Ying; Li, Min

    2013-04-01

    To review the research progress of cell-scaffold complex in the tendon tissue engineering. Recent literature concerning cell-scaffold complex in the tendon tissue engineering was reviewed, the research situation of the cell-scaffold complex was elaborated in the aspects of seed cells, scaffolds, cell culture, and application. In tendon tissue engineering, a cell-scaffold complex is built by appropriate seed cells and engineered scaffolds. Experiments showed that modified seed cells had better therapeutic effects. Further, scaffold functionality could be improved through surface modification, growth factor cure, mechanical stimulation, and contact guidance. Among these methods, mechanical stimulation revealed the most significant results in promoting cell proliferation and function. Through a variety of defect models, it is demonstrated that the use of cell-scaffold complex could achieve satisfactory results for tendon regeneration. The cell-scaffold complex for tendon tissue engineering is a popular research topic. Although it has not yet met the requirement of clinical use, it has broad application prospects.

  18. Specialisation of extracellular matrix for function in tendons and ligaments

    PubMed Central

    Birch, Helen L.; Thorpe, Chavaunne T.; Rumian, Adam P.

    2013-01-01

    Summary Tendons and ligaments are similar structures in terms of their composition, organisation and mechanical properties. The distinction between them stems from their anatomical location; tendons form a link between muscle and bone while ligaments link bones to bones. A range of overlapping functions can be assigned to tendon and ligaments and each structure has specific mechanical properties which appear to be suited for particular in vivo function. The extracellular matrix in tendon and ligament varies in accordance with function, providing appropriate mechanical properties. The most useful framework in which to consider extracellular matrix differences therefore is that of function rather than anatomical location. In this review we discuss what is known about the relationship between functional requirements, structural properties from molecular to gross level, cellular gene expression and matrix turnover. The relevance of this information is considered by reviewing clinical aspects of tendon and ligament repair and reconstructive procedures. PMID:23885341

  19. Micro-mechanical properties of the tendon-to-bone attachment.

    PubMed

    Deymier, Alix C; An, Yiran; Boyle, John J; Schwartz, Andrea G; Birman, Victor; Genin, Guy M; Thomopoulos, Stavros; Barber, Asa H

    2017-07-01

    The tendon-to-bone attachment (enthesis) is a complex hierarchical tissue that connects stiff bone to compliant tendon. The attachment site at the micrometer scale exhibits gradients in mineral content and collagen orientation, which likely act to minimize stress concentrations. The physiological micromechanics of the attachment thus define resultant performance, but difficulties in sample preparation and mechanical testing at this scale have restricted understanding of structure-mechanical function. Here, microscale beams from entheses of wild type mice and mice with mineral defects were prepared using cryo-focused ion beam milling and pulled to failure using a modified atomic force microscopy system. Micromechanical behavior of tendon-to-bone structures, including elastic modulus, strength, resilience, and toughness, were obtained. Results demonstrated considerably higher mechanical performance at the micrometer length scale compared to the millimeter tissue length scale, describing enthesis material properties without the influence of higher order structural effects such as defects. Micromechanical investigation revealed a decrease in strength in entheses with mineral defects. To further examine structure-mechanical function relationships, local deformation behavior along the tendon-to-bone attachment was determined using local image correlation. A high compliance zone near the mineralized gradient of the attachment was clearly identified and highlighted the lack of correlation between mineral distribution and strain on the low-mineral end of the attachment. This compliant region is proposed to act as an energy absorbing component, limiting catastrophic failure within the tendon-to-bone attachment through higher local deformation. This understanding of tendon-to-bone micromechanics demonstrates the critical role of micrometer scale features in the mechanics of the tissue. The tendon-to-bone attachment (enthesis) is a complex hierarchical tissue with features at

  20. Achilles Tendon Loading During Heel-Raising and -Lowering Exercises

    PubMed Central

    Revak, Andrew; Diers, Keith; Kernozek, Thomas W.; Gheidi, Naghmeh; Olbrantz, Christina

    2017-01-01

    Context: Achilles tendinopathies are common injuries during sport participation, although men are more prone to Achilles tendon injuries than women. Heel-raising and -lowering exercises are typically suggested for Achilles tendon rehabilitation. Objective: To compare the estimated Achilles tendon loading variables and the ankle range of motion (ROM) using a musculoskeletal model during commonly performed heel-raising and -lowering exercises. Design: Controlled laboratory study. Setting: University biomechanics laboratory. Patients or Other Participants: Twenty-one healthy men (age = 21.59 ± 1.92 years, height = 178.22 ± 8.02 cm, mass = 75.81 ± 11.24 kg). Intervention(s): Each participant completed 4 exercises: seated heel raising and lowering, bilateral standing heel raising and lowering, bilateral heel raising and unilateral lowering, and unilateral heel raising and lowering. Main Outcome Measure(s): A repeated-measures multivariate analysis of variance (α = .05) was used to compare Achilles tendon stress, force, and strain and ankle ROM for each exercise. Kinematic data were recorded at 180 Hz with 15 motion-analysis cameras synchronized with kinetic data collected from a force platform sampled at 1800 Hz. These data were then entered in a musculoskeletal model to estimate force in the triceps surae. For each participant, we determined Achilles tendon stress by measuring cross-sectional images using ultrasound. Results: Peak Achilles tendon loading was lowest when performing the seated heel-raising and -lowering exercise and highest when performing the unilateral heel-raising and -lowering exercise. Loading was greater for the unilateral exercise or portions of the exercise that were performed unilaterally. Conclusions: Bilateral and seated exercises with less weight-bearing force resulted in less Achilles tendon loading. These exercises may serve as progressions during the rehabilitation process before full-body weight-bearing, unilateral exercises are

  1. Investigation of a tissue engineered tendon model by PS-OCT

    NASA Astrophysics Data System (ADS)

    Yang, Ying; Ahearne, Mark; Wimpenny, Ian; Guijarro-Leach, Juan; Torbet, Jim

    2010-02-01

    A few native tissues, such as tendon, skin and eye, possess highly organized collagenous matrices. In particular, the collagen fibers in tendon are organized into a hierarchical and unidirectional format, which gives rise to the high tissuespecific mechanical properties. This organization has been clearly revealed by a conventional polarized light microscope. The newly developed polarization-sensitive optical coherence tomography (PS-OCT) technique allows non-invasive visualization of birefringence images arising from orientated structures in a three dimensional format. Our previous studies of native tendon and tissue engineered tendon by PS-OCT demonstrate that tissue engineered tendon has a far less perfect collagen fiber organization than native tendon even under dynamic culture conditions. The purpose of this study is to use PS-OCT to assess the relationship between the degree of birefringence, collagen concentration and fiber density in model tendon tissues. The model tissue is constructed from an aligned collagen hydrogel and aligned polyester nanofibers. The effects of the diameter and density of the nanofibers and the collagen concentration in the model have been investigated. The alignment of collagen fibrils is induced by application of a high magnetic field during fibrillogenesis while aligned polyester nanofibers are manufactured using the electrospinning technique. It is found that the collagen concentration, the density and size of nanofiber bundles are the key parameters to produce birefringence in OCT images. The perfectly aligned collagen hydrogel with concentration as high as 4 mg/ml does not exhibit a birefringence image until the hydrogel has been compressed and concentrated. Aligned nanofiber bundles have demonstrated marginal birefringence in the absence of the collagen matrix. These studies enhance our understanding of how to control and optimize the parameters in tendon tissue engineering.

  2. Enhanced tenogenic differentiation and tendon-like tissue formation by CHIP overexpression in tendon-derived stem cells.

    PubMed

    Han, Weifeng; Chen, Lei; Liu, Junpeng; Guo, Ai

    2017-04-01

    The carboxyl terminus of Hsc70-interacting protein (CHIP, also known as STUB1) plays critical roles in the proliferation and differentiation of many types of cells. The potential function of CHIP in tendon-derived stem cells (TDSCs) remains largely unknown at present. Here, we investigated the effects of CHIP on tenogenic differentiation of TDSCs via lentivirus-mediated overexpression. Forced expression of CHIP induced morphological changes and significantly enhanced cell proliferation, as well as tendon differentiation in vitro. Upon stimulation with differentiation induction medium, CHIP-overexpressing TDSCs displayed significant inhibition of differentiation into osteogenic and adipogenic lineages. Subsequent implantation of TDSCs overexpressing CHIP with collagen sponges into nude mice induced a marked increase in ectopic tendon formation in vivo, compared with the control group. Our findings collectively suggest that CHIP is an important contributory factor to tenogenic tissue formation. © The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Hypogravity-induced atrophy of rat soleus and extensor digitorum longus muscles

    NASA Technical Reports Server (NTRS)

    Riley, D. A.; Ellis, S.; Slocum, G. R.; Satyanarayana, T.; Bain, J. L.; Sedlak, F. R.

    1987-01-01

    Prolonged exposure of humans to hypogravity causes weakening of their skeletal muscles. This problem was studied in rats exposed to hypogravity for 7 days aboard Spacelab 3. Hindlimb muscles were harvested 12-16 hours postflight for histochemical, biochemical, and ultrastructural analyses. The majority of the soleus and extensor digitorum longus fibers exhibited simple cell shrinkage. However, approximately 1% of the fibers in flight soleus muscles appeared necrotic. Flight muscle fibers showed increased glycogen, lower subsarcolemmal staining for mitochondrial enzymes, and fewer subsarcolemmal mitochondria. During atrophy, myofibrils were eroded by multiple focal losses of myofilaments; lysosomal autophagy was not evident. Tripeptidylaminopeptidase and calcium-activated protease activities of flight soleus fibers were significantly increased, implying a role in myofibril breakdown. Simple fiber atrophy appears to account for muscle weakening during spaceflight, but fiber necrosis is also a contributing factor.

  4. Fascicles and the interfascicular matrix show decreased fatigue life with ageing in energy storing tendons.

    PubMed

    Thorpe, Chavaunne T; Riley, Graham P; Birch, Helen L; Clegg, Peter D; Screen, Hazel R C

    2017-07-01

    Tendon is composed of rope-like fascicles bound together by interfascicular matrix (IFM). The IFM is critical for the function of energy storing tendons, facilitating sliding between fascicles to allow these tendons to cyclically stretch and recoil. This capacity is required to a lesser degree in positional tendons. We have previously demonstrated that both fascicles and IFM in energy storing tendons have superior fatigue resistance compared with positional tendons, but the effect of ageing on the fatigue properties of these different tendon subunits has not been determined. Energy storing tendons become more injury-prone with ageing, indicating reduced fatigue resistance, hence we tested the hypothesis that the decline in fatigue life with ageing in energy storing tendons would be more pronounced in the IFM than in fascicles. We further hypothesised that tendon subunit fatigue resistance would not alter with ageing in positional tendons. Fascicles and IFM from young and old energy storing and positional tendons were subjected to cyclic fatigue testing until failure, and mechanical properties were calculated. The results show that both IFM and fascicles from the SDFT exhibit a similar magnitude of reduced fatigue life with ageing. By contrast, the fatigue life of positional tendon subunits was unaffected by ageing. The age-related decline in fatigue life of tendon subunits in energy storing tendons is likely to contribute to the increased risk of injury in aged tendons. Full understanding of the mechanisms resulting in this reduced fatigue life will aid in the development of treatments and interventions to prevent age-related tendinopathy. Understanding the effect of ageing on tendon-structure function relationships is crucial for the development of effective preventative measures and treatments for age-related tendon injury. In this study, we demonstrate for the first time that the fatigue resistance of the interfascicular matrix decreases with ageing in energy

  5. Eccentric Training for Tendon Healing After Acute Lesion: A Rat Model.

    PubMed

    Kaux, Jean-François; Libertiaux, Vincent; Leprince, Pierre; Fillet, Marianne; Denoel, Vincent; Wyss, Clémence; Lecut, Christelle; Gothot, André; Le Goff, Caroline; Croisier, Jean-Louis; Crielaard, Jean-Michel; Drion, Pierre

    2017-05-01

    The tendon is a dynamic entity that remodels permanently. Platelet-rich plasma (PRP) injection has been shown to have a beneficial effect on tendon healing after lesion in rats. Furthermore, eccentric exercise seems to improve the mechanical quality of the tendon. A combination of PRP injection and eccentric training might be more effective than either treatment alone. Controlled laboratory study. Adult male rats were anesthetized, an incision was performed in the middle of their left patellar tendon and an injection of physiological fluid (PF) or homologous PRP was randomly made at the lesion level. The rats were then divided into 2 groups: the eccentric group, undergoing eccentric training 3 times a week, and the untrained group, without any training. Thus, 4 groups were compared. After 5 weeks, the tendons were removed and their ultimate tensile strength and energy were measured. Tendons were frozen for proteomic analyses when all biomechanical tests were completed. Statistical analysis was performed with linear mixed effect models. No significant difference was found between the treatments using PF injection or PRP injection alone. However, the value of the ultimate tensile force at rupture was increased by 4.5 N (108% of control, P = .006) when eccentric training was performed. An intragroup analysis revealed that eccentric training significantly improved the ultimate force values for the PRP group. Proteomic analysis revealed that eccentric training led to an increase in abundance of several cytoskeletal proteins in the PF group, while a decrease in abundance of enzymes of the glycolytic pathway occurred in the PRP-treated groups, indicating that this treatment might redirect the exercise-driven metabolic plasticity of the tendon. Eccentric training altered the metabolic plasticity of tendon and led to an improvement of injured tendon resistance regardless of the treatment injected (PF or PRP). This study demonstrates the necessity of eccentric rehabilitation

  6. Observation of tendon repair in animal model using second-harmonic-generation microscopy

    NASA Astrophysics Data System (ADS)

    Hase, Eiji; Minamikawa, Takeo; Sato, Katsuya; Takahashi, Mitsuhiko; Yasui, Takashi

    2016-03-01

    Tendon rupture is a trauma difficult to recover the condition before injury. In previous researches, tensile test and staining method have been widely used to elucidate the mechanism of the repair process from the viewpoints of the mechanical property and the histological findings. However, since both methods are destructive and invasive, it is difficult to obtain both of them for the same sample. If both the mechanical property and the histological findings can be obtained from the same sample, one may obtain new findings regarding mechanisms of tendon repairing process. In this paper, we used second-harmonic-generation (SHG) microscopy, showing high selectivity and good image contrast to collagen molecules as well as high spatial resolution, optical three-dimensional sectioning, deep penetration, and without additional staining. Since SHG light intensity sensitively reflects the structural maturity of collagen molecule and its aggregates, it will be a good indicator for the repairing degree of the ruptured tendon. From comparison of SHG images between the 4-weeks-repaired tendon and the sound tendon in the animal model, we confirmed that SHG light intensity of the repaired tendon was significantly lower than that of the sound tendon, indicating that the collagen structure in the repaired tendon is still immature. Furthermore, we performed both SHG imaging and the tensile test for the same sample, and confirmed a correlation between them. This result shows a potential of SHG light for an indicator of the histological and mechanical recovery of the ruptured tendon.

  7. Do athletes alter their running mechanics after an Achilles tendon rupture?

    PubMed

    Jandacka, Daniel; Silvernail, Julia Freedman; Uchytil, Jaroslav; Zahradnik, David; Farana, Roman; Hamill, Joseph

    2017-01-01

    Over the past thirty years, there has been dramatic increase in incidence of Achilles tendon rupture in the athletic population. The purpose of this study was to compare the lower extremity mechanics of Achilles tendon ruptured runners with healthy controls. The participants with a past history of an Achilles tendon repair ( n  = 11) and healthy control ( n  = 11) subgroups were matched on sex, age, type of regular physical activity, mass, height, footfall pattern and lateral dominancy. Running kinetics and kinematics of the ankle, knee and hip were recorded using a high-speed motion capture system interfaced with a force platform. Achilles tendon length was measured using ultrasonography. Main outcome measures were lower extremity joint angles and moments during stance phase of running and Achilles tendon lengths. Athletes from Achilles tendon group had an affected gastro-soleus complex. Athletes with history of Achilles tendon rupture had reduced ankle range of motion during second half of the stance phase of running (Δ7.6°), an overextended knee during initial contact (Δ5.2°) and increased affected knee range of motion (Δ4.4°) during the first half of stance phase on their affected limb compared to the healthy control group. There was a 22% increase in the maximal hip joint moment on contralateral side of the Achilles tendon group compared to the healthy controls. These results suggest a compensation mechanism, relatively extended knee at initial ground contact against the deficit in the muscle-tendon complex of the triceps surae. Overextension during sporting activities may place the knee at risk for further injury. Avoidance of AT lengthening and plantarflexion strength deficit after surgery and during rehabilitation might help to manage AT rupture since these factors may be responsible for altered running kinematics.

  8. Tendon Tissue Engineering and Its Role on Healing of the Experimentally Induced Large Tendon Defect Model in Rabbits: A Comprehensive In Vivo Study

    PubMed Central

    Meimandi-Parizi, Abdolhamid; Oryan, Ahmad; Moshiri, Ali

    2013-01-01

    Healing of large tendon defects is challenging. We studied the role of collagen implant with or without polydioxanone (PDS) sheath on the healing of a large Achilles tendon defect model, in rabbits. Sixty rabbits were divided into three groups. A 2 cm gap was created in the left Achilles tendon of all rabbits. In the control lesions, no implant was used. The other two groups were reconstructed by collagen and collagen-PDS implants respectively. The animals were clinically examined at weekly intervals and their lesions were observed by ultrasonography. Blood samples were obtained from the animals and were assessed for hematological analysis and determination of serum PDGF level, at 60 days post injury (DPI). The animals were then euthanized and their lesions were assessed for gross and histopathology, scanning electron microscopy, biomechanical testing, dry matter and hydroxyproline content. Another 65 pilot animals were also studied grossly and histopathologically to define the host implant interaction and graft incorporation at serial time points. The treated animals gained significantly better clinical scoring compared to the controls. Treatment with collagen and collagen-PDS implants significantly increased the biomechanical properties of the lesions compared to the control tendons at 60DPI (P<0.05). The tissue engineered implants also reduced peritendinous adhesion, muscle fibrosis and atrophy, and increased ultrasonographical echogenicity and homogenicity, maturation and differentiation of the collagen fibrils and fibers, tissue alignment and volume of the regenerated tissue compared to those of the control lesions (P<0.05). The implants were gradually absorbed and substituted by the new tendon. Implantation of the bioimplants had a significant role in initiating tendon healing and the implants were biocompatible, biodegradable and safe for application in tendon reconstructive surgery. The results of the present study may be valuable in clinical practice. PMID

  9. The Accuracy of the VISA-P Questionnaire, Single-Leg Decline Squat, and Tendon Pain History to Identify Patellar Tendon Abnormalities in Adult Athletes.

    PubMed

    Mendonça, Luciana de Michelis; Ocarino, Juliana Melo; Bittencourt, Natália Franco Netto; Fernandes, Ludmila Maria Oliveira; Verhagen, Evert; Fonseca, Sérgio Teixeira

    2016-08-01

    Study Design Cross-sectional clinical assessment. Background Patellar tendinopathy is not always accompanied by patellar tendon abnormalities (PTAs). Thus, clinical screening tools to help identify patients with patellar tendon pain who have PTAs could enhance clinical decision making and patient prognosis. Objectives To test the diagnostic accuracy of the Victorian Institute of Sport Assessment-Patella (VISA-P) questionnaire, a single-leg decline squat (SLDS), tendon pain history, age, and years of sports participation to identify athletes with symptomatic patellar tendons who have PTAs confirmed on imaging. Methods Data provided by ultrasound examination, the VISA-P questionnaire, the SLDS, tendon pain history, age, and years of sport participation were collected in 43 athletes. A classification and regression tree (CART) model was developed to verify variables associated with PTA occurrence. Likelihood ratios (LRs) were computed for positive and negative tests. Results The SLDS, VISA-P questionnaire, and tendon pain history were associated with PTA occurrence. Athletes with negative results on all 3 tests (CART model) had a lower likelihood of having PTAs (negative LR = 0.3; 95% confidence interval [CI]: 0.2, 0.5). The isolated use of the SLDS or tendon pain history (positive LR = 4.2; 95% CI: 2.3, 7.14 and 4.5; 95% CI: 1.8, 11.1, respectively) had similar influence on probability of PTA presence compared to the CART model (positive LR = 4.1; 95% CI: 2.5, 6.3). Conclusion Although the objective was to investigate a clinical test to identify PTAs, the combined use of the tests had greater accuracy to identify individuals without PTAs. Level of Evidence Diagnosis, level 3b. J Orthop Sports Phys Ther 2016;46(8):673-680. Epub 3 Jul 2016. doi:10.2519/jospt.2016.6192.

  10. Tendon Tissue Engineering: Progress, Challenges, and Translation to the Clinic

    PubMed Central

    Shearn, Jason T.; Kinneberg, Kirsten R.C.; Dyment, Nathaniel A.; Galloway, Marc T.; Kenter, Keith; Wylie, Christopher; Butler, David L.

    2013-01-01

    The tissue engineering field has made great strides in understanding how different aspects of tissue engineered constructs (TECs) and the culture process affect final tendon repair. However, there remain significant challenges in developing strategies that will lead to a clinically effective and commercially successful product. In an effort to increase repair quality, a better understanding of normal development, and how it differs from adult tendon healing, may provide strategies to improve tissue engineering. As tendon tissue engineering continues to improve, the field needs to employ more clinically relevant models of tendon injury such as degenerative tendons. We need to translate successes to larger animal models to begin exploring the clinical implications of our treatments. By advancing the models used to validate our TECs, we can help convince our toughest customer, the surgeon, that our products will be clinically efficacious. As we address these challenges in musculoskeletal tissue engineering, the field still needs to address the commercialization of products developed in the laboratory. TEC commercialization faces numerous challenges because each injury and patient is unique. This review aims to provide tissue engineers with a summary of important issues related to engineering tendon repairs and potential strategies for producing clinically successful products. PMID:21625053

  11. Delayed Exercise Promotes Remodeling in Sub-Rupture Fatigue Damaged Tendons

    PubMed Central

    Bell, R.; Boniello, M.R.; Gendron, N.R.; Flatow, E.L.; Andarawis-Puri, N.

    2015-01-01

    Tendinopathy is a common musculoskeletal injury whose treatment is limited by ineffective therapeutic interventions. Previously we have shown that tendons ineffectively repair early sub-rupture fatigue damage. In contrast, physiological exercise has been shown to promote remodeling of healthy tendons but its utility as a therapeutic to promote repair of fatigue damaged tendons remains unknown. Therefore, the objective of this study was to assess the utility of exercise initiated 1 and 14 days after onset of fatigue damage to promote structural repair in fatigue damaged tendons. We hypothesized that exercise initiated 14 days after fatigue loading would promote remodeling as indicated by a decrease in area of collagen matrix damage, increased procollagen I and decorin, while decreasing proteins indicative of tendinopathy. Rats engaged in 6-week exercise for 30 min/day or 60 min/day starting 1 or 14 days after fatigue loading. Initiating exercise 1-day after onset of fatigue injury led to exacerbation of matrix damage, particularly at the tendon insertion. Initiating exercise 14 days after onset of fatigue injury led to remodeling of damaged regions in the midsubstance and collagen synthesis at the insertion. Physiological exercise applied after the initial biological response to injury has dampened can potentially promote remodeling of damaged tendons. PMID:25732052

  12. Suture anchor tenodesis in repair of distal Achilles tendon injuries.

    PubMed

    Kiliçoğlu, Onder; Türker, Mehmet; Yildız, Fatih; Akalan, Ekin; Temelli, Yener

    2014-01-01

    Distal Achilles tendon avulsions are in the form of either bony and nonbony avulsion of Achilles tendon from its calcaneal insertion. Four patients with distal Achilles tendon avulsions or ruptures which were treated with tendon to bone repair using suture anchors are presented here. Operated leg was immobilized in above-knee cast for 4 weeks while the patient walked non-weight-bearing. Then, cast was changed to below knee, and full weight-bearing was allowed. Patients underwent gait analysis minimum at first postoperative year. Mean American Orthopedics Foot Ankle Society ankle/hindfoot score of patients at last visit was 88.75 (range 85-100), and Achilles tendon total rupture score was 77.75 (range 58-87). Mean passive dorsiflexion of injured ankles (14° ± 5°) was lower than uninjured ankles (23° ± 9°). All the kinematic parameters of gait analysis were comparable to the uninjured side. Maximum plantar flexion power of injured ankle was 1.40 W/kg, and this was significantly lower than the contralateral side value 2.38 W/kg; (P = 0.0143). There were no visually altered gait or problems in daily life. Suture anchor tenodesis technique of distal Achilles tendon avulsions was successful in achieving durable osteotendinous repairs.

  13. Stem cell technology for tendon regeneration: current status, challenges, and future research directions

    PubMed Central

    Lui, Pauline Po Yee

    2015-01-01

    Tendon injuries are a common cause of physical disability. They present a clinical challenge to orthopedic surgeons because injured tendons respond poorly to current treatments without tissue regeneration and the time required for rehabilitation is long. New treatment options are required. Stem cell-based therapies offer great potential to promote tendon regeneration due to their high proliferative, synthetic, and immunomodulatory activities as well as their potential to differentiate to the target cell types and undergo genetic modification. In this review, I first recapped the challenges of tendon repair by reviewing the anatomy of tendon. Next, I discussed the advantages and limitations of using different types of stem cells compared to terminally differentiated cells for tendon tissue engineering. The safety and efficacy of application of stem cells and their modified counterparts for tendon tissue engineering were then summarized after a systematic literature search in PubMed. The challenges and future research directions to enhance, optimize, and standardize stem cell-based therapies for augmenting tendon repair were then discussed. PMID:26715856

  14. PAPP-A affects tendon structure and mechanical properties.

    PubMed

    Yang, Tai-Hua; Thoreson, Andrew R; An, Kai-Nan; Zhao, Chunfeng; Conover, Cheryl A; Amadio, Peter C

    2015-10-01

    Pregnancy-associated plasma protein-A (PAPP-A) serves to increase local insulin-like growth factor (IGF) stimulation of proliferation and differentiation in many tissues through proteolysis of inhibitory IGF-binding proteins. The purpose of this study was to investigate the effects of PAPP-A on tendon structure and mechanical properties. A total of 30 tails from 6-month-old mice were tested with 10 tails in each of following groups: PAPP-A knockout (KO), skeletal-specific PAPP-A overexpressing transgenic (Tg) and wild type (WT). Morphologically, the total tail cross-sectional area (CSA), individual tissue CSAs of bone, muscle and tendon, and fascicle diameter were measured. A fascicle pullout test was performed to assess stiffness and strength of interfascicular structures. Fascicles were mechanically characterized through low and high displacement rate uniaxial tension tests providing modulus at each rate, hysteresis area and stress relaxation ratio. The KO mice had a smaller total tail CSA (p<0.05), fascicle diameter (p<0.05), absolute tendon CSA (p<0.05), fast and slow stiffness (p<0.05 for both) and larger hysteresis area (p<0.05) compared to WT and Tg mice. On the other hand, the Tg mice had a larger fascicle diameter (p<0.05), absolute tendon CSA (p<0.05), higher interfascicular strength and stiffness (p<0.05) and lower fascicular modulus at low displacement rates (p<0.05) compared to WT and KO mice. Tg mice also had larger total tail CSA area (p<0.05) and smaller hysteresis area (p<0.05) than KO mice, and larger normalized tendon CSA (p<0.05) than WT mice. Based on these data, we conclude that PAPP-A affects fascicle structure, thereby affecting tendon phenotype. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Diabetes Alters Mechanical Properties and Collagen Fiber Re-Alignment in Multiple Mouse Tendons

    PubMed Central

    Connizzo, Brianne K.; Bhatt, Pankti R.; Liechty, Kenneth W.; Soslowsky, Louis J.

    2014-01-01

    Tendons function to transfer load from muscle to bone through their complex composition and hierarchical structure, consisting mainly of type I collagen. Recent evidence suggests that type II diabetes may cause alterations in collagen structure, such as irregular fibril morphology and density, which could play a role in the mechanical function of tendons. Using the db/db mouse model of type II diabetes, the diabetic skin was found to have impaired biomechanical properties when compared to the non-diabetic group. The purpose of this study was to assess the effect of diabetes on biomechanics, collagen fiber re-alignment, and biochemistry in three functionally different tendons (Achilles, supraspinatus, patellar) using the db/db mouse model. Results showed that cross-sectional area and stiffness, but not modulus, were significantly reduced in all three tendons. However, the tendon response to load (transition strain, collagen fiber re-alignment) occurred earlier in the mechanical test, contrary to expectations. In addition, the patellar tendon had an altered response to diabetes when compared to the other two tendons, with no changes in fiber realignment and decreased collagen content at the midsubstance of the tendon. Overall, type II diabetes alters tendon mechanical properties and the dynamic response to load. PMID:24833253

  16. Patellar tendon re-rupture on the opposite end of the previous site of surgical repair

    PubMed Central

    KOH, Bryan Thean Howe; SAYAMPANATHAN, Andrew A; LEE, Keng Thiam

    2017-01-01

    We describe a rare case of a patellar tendon “re-rupture” at the opposite end of a previous proximal tendon repair. A 32-year-old male with a history of surgically repaired right proximal patellar tendon rupture presented with an acute non-traumatic right knee pain and instability during sports. Magnetic resonance imaging confirmed a complete rupture of his distal patellar tendon at the tibial tuberosity. The patellar tendon was repaired using two 5.5 mm BioCorkscrews (Arthrex) inserted into the tibial tuberosity; the tendon was stitched with the No. 2 fiberwires using Krackow technique. As the patellar tendon was degenerative, the repair was augmented with a semitendinosus tendon harvested using an open tendon stripper, leaving the distal attachment intact. At 2.6 years followup he had mild anterior knee pain, range of motion 0-130° and was able to squat. MRI scan done at followup revealed good healing of repaired patellar tendon. PMID:28566788

  17. Tendon fatigue in response to mechanical loading

    PubMed Central

    Andarawis-Puri, N.; Flatow, E. L.

    2015-01-01

    Tendinopathies are commonly attributable to accumulation of sub-rupture fatigue damage from repetitive use. Data is limited to late stage disease from patients undergoing surgery, motivating development of animal models, such as ones utilizing treadmill running or repetitive reaching, to investigate the progression of tendinopathies. We developed an in vivo model using the rat patellar tendon that allows control of the loading directly applied to the tendon. This manuscript discusses the response of tendons to fatigue loading and applications of our model. Briefly, the fatigue life of the tendon was used to define low, moderate and high levels of fatigue loading. Morphological assessment showed a progression from mild kinks to fiber disruption, for low to high level fatigue loading. Collagen expression, 1 and 3 days post loading, showed more modest changes for low and moderate than high level fatigue loading. Protein and mRNA expression of Ineterleukin-1β and MMP-13 were upregulated for moderate but not low level fatigue loading. Moderate level (7200 cycles) and 100 cycles of fatigue loading resulted in a catabolic and anabolic molecular profile respectively, at both 1 and 7 days post loading. Results suggest unique mechanisms for different levels of fatigue loading that are distinct from laceration. PMID:21625047

  18. Radiographic Features of Acute Patellar Tendon Rupture.

    PubMed

    Fazal, Muhammad Ali; Moonot, Pradeep; Haddad, Fares

    2015-11-01

    The purpose of our study was to assess soft tissue features of acute patellar tendon rupture on lateral knee radiograph that would facilitate early diagnosis. The participants were divided into two groups of 35 patients each. There were 28 men and seven women with a mean age of 46 years in the control group and 26 men and nine women with a mean age of 47 years in the rupture group. The lateral knee radiograph of each patient was evaluated for Insall-Salvati ratio for patella alta, increased density of the infrapatellar fat pad, appearance of the soft tissue margin of the patellar tendon and bony avulsions. In the rupture group there were three consistent soft tissue radiographic features in addition to patellar alta. These were increased density of infrapatellar fat pad; loss of sharp, well-defined linear margins of the patellar tendon and angulated wavy margin of the patellar tendon while in the control group these features were not observed. The soft tissue radiographic features described in the rupture group are consistent and reliable. When coupled with careful clinical assessment, these will aid in early diagnosis and further imaging will be seldom required. © 2015 Chinese Orthopaedic Association and Wiley Publishing Asia Pty Ltd.

  19. Extracellular matrix adaptation of tendon and skeletal muscle to exercise

    PubMed Central

    Kjær, Michael; Magnusson, Peter; Krogsgaard, Michael; Møller, Jens Boysen; Olesen, Jens; Heinemeier, Katja; Hansen, Mette; Haraldsson, Bjarki; Koskinen, Satu; Esmarck, Birgitte; Langberg, Henning

    2006-01-01

    The extracellular matrix (ECM) of connective tissues enables linking to other tissues, and plays a key role in force transmission and tissue structure maintenance in tendons, ligaments, bone and muscle. ECM turnover is influenced by physical activity, and both collagen synthesis and metalloprotease activity increase with mechanical loading. This can be shown by determining propeptide and proteinase activity by microdialysis, as well as by verifying the incorporation of infused stable isotope amino acids in biopsies. Local tissue expression and release of growth factors for ECM such as IGF-1, TGF-beta and IL-6 is enhanced following exercise. For tendons, metabolic activity (e.g. detected by positron emission tomography scanning), circulatory responses (e.g. as measured by near-infrared spectroscopy and dye dilution) and collagen turnover are markedly increased after exercise. Tendon blood flow is regulated by cyclooxygenase-2 (COX-2)-mediated pathways, and glucose uptake is regulated by specific pathways in tendons that differ from those in skeletal muscle. Chronic loading in the form of physical training leads both to increased collagen turnover as well as to some degree of net collagen synthesis. These changes modify the mechanical properties and the viscoelastic characteristics of the tissue, decrease its stress-susceptibility and probably make it more load-resistant. The mechanical properties of tendon fascicles vary within a given human tendon, and even show gender differences. The latter is supported by findings of gender-related differences in the activation of collagen synthesis with exercise. These findings may provide the basis for understanding tissue overloading and injury in both tendons and skeletal muscle. PMID:16637870

  20. Chronic Achilles Tendon Disorders: Tendinopathy and Chronic Rupture.

    PubMed

    Maffulli, Nicola; Via, Alessio Giai; Oliva, Francesco

    2015-10-01

    Tendinopathy of the Achilles tendon involves clinical conditions in and around the tendon and it is the result of a failure of a chronic healing response. Although several conservative therapeutic options have been proposed, few of them are supported by randomized controlled trials. The management is primarily conservative and many patients respond well to conservative measures. If clinical conditions do not improve after 6 months of conservative management, surgery is recommended. The management of chronic ruptures is different from that of acute ruptures. The optimal surgical procedure is still debated. In this article chronic Achilles tendon disorders are debated and evidence-based medicine treatment strategies are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Ruptured Tendons in Anabolic-Androgenic Steroid Users: A Cross-Sectional Cohort Study

    PubMed Central

    Kanayama, Gen; DeLuca, James; Meehan, William P.; Hudson, James I.; Isaacs, Stephanie; Baggish, Aaron; Weiner, Rory; Micheli, Lyle; Pope, Harrison G.

    2016-01-01

    Background Accumulating case reports have described tendon rupture in men using anabolic-androgenic steroids (AAS). However no controlled study, to our knowledge, has assessed history of tendon rupture in a large cohort of AAS users and comparison nonusers. Hypothesis We hypothesized that men reporting long-term AAS abuse would report an elevated lifetime incidence of tendon rupture as compared to non-AAS-using bodybuilders. Study Design Cross-sectional cohort study. Methods We obtained medical histories from 142 experienced male bodybuilders age 35–55, recruited in the course of two studies. Of these men, 88 reported at least two years of cumulative lifetime AAS use and 54 reported no history of AAS use. In men reporting a history of tendon rupture, we recorded circumstances of the injury, prodromal symptoms, concomitant drug or alcohol use, and details of current and lifetime AAS use if applicable. We also obtained surgical records for most participants. Results Nineteen (22%) of the AAS users, but only 3 (6%) of the nonusers reported at least one lifetime tendon rupture. The hazard ratio (95% confidence interval) for a first ruptured tendon in AAS users versus nonusers was 9.0 (2.5, 32.3); P <.001. Several men reported two or more independent lifetime tendon ruptures. Interestingly, upper body tendon ruptures occurred exclusively in the AAS group (15 [17%] of the AAS users versus 0 non-users; risk difference 0.17 (0.09, 0.25); P < 0.001 [hazard ratio not estimable]), whereas we found no significant difference between users and nonusers in risk for lower body ruptures (6 [7%] AAS users, 3 [6%] nonusers; hazard ratio 3.1 (0.7, 13.8), P = 0.13). Of 31 individual tendon ruptures that we assessed, only 6 (19%) occurred while weightlifting, with the majority occurring during other sports activities. Eight (26%) ruptures followed prodromal symptoms of nonspecific pain in the region. Virtually all ruptures were treated surgically with complete or near

  2. Triceps surae muscle-tendon properties in older endurance- and sprint-trained athletes.

    PubMed

    Stenroth, Lauri; Cronin, Neil J; Peltonen, Jussi; Korhonen, Marko T; Sipilä, Sarianna; Finni, Taija

    2016-01-01

    Previous studies have shown that aging is associated with alterations in muscle architecture and tendon properties (Morse CI, Thom JM, Birch KM, Narici MV. Acta Physiol Scand 183: 291-298, 2005; Narici MV, Maganaris CN, Reeves ND, Capodaglio P. J Appl Physiol 95: 2229-2234, 2003; Stenroth L, Peltonen J, Cronin NJ, Sipila S, Finni T. J Appl Physiol 113: 1537-1544, 2012). However, the possible influence of different types of regular exercise loading on muscle architecture and tendon properties in older adults is poorly understood. To address this, triceps surae muscle-tendon properties were examined in older male endurance (OE, n = 10, age = 74.0 ± 2.8 yr) and sprint runners (OS, n = 10, age = 74.4 ± 2.8 yr), with an average of 42 yr of regular training experience, and compared with age-matched [older control (OC), n = 33, age = 74.8 ± 3.6 yr] and young untrained controls (YC, n = 18, age = 23.7 ± 2.0 yr). Compared with YC, Achilles tendon cross-sectional area (CSA) was 22% (P = 0.022), 45% (P = 0.001), and 71% (P < 0.001) larger in OC, OE, and OS, respectively. Among older groups, OS had significantly larger tendon CSA compared with OC (P = 0.033). No significant between-group differences were observed in Achilles tendon stiffness. In older groups, Young's modulus was 31-44%, and maximal tendon stress 44-55% lower, than in YC (P ≤ 0.001). OE showed shorter soleus fascicle length than both OC (P < 0.05) and YC (P < 0.05). These data suggest that long-term running does not counteract the previously reported age-related increase in tendon CSA, but, instead, may have an additive effect. The greatest Achilles tendon CSA was observed in OS followed by OE and OC, suggesting that adaptation to running exercise is loading intensity dependent. Achilles tendon stiffness was maintained in older groups, even though all older groups displayed larger tendon CSA and lower tendon Young's modulus. Shorter soleus muscle fascicles in OE runners may be an adaptation to life

  3. Ruptured Tendons in Anabolic-Androgenic Steroid Users: A Cross-Sectional Cohort Study.

    PubMed

    Kanayama, Gen; DeLuca, James; Meehan, William P; Hudson, James I; Isaacs, Stephanie; Baggish, Aaron; Weiner, Rory; Micheli, Lyle; Pope, Harrison G

    2015-11-01

    Accumulating case reports have described tendon rupture in men who use anabolic-androgenic steroids (AAS). However, no controlled study has assessed the history of tendon rupture in a large cohort of AAS users and comparison nonusers. Men reporting long-term AAS abuse would report an elevated lifetime incidence of tendon rupture compared with non-AAS-using bodybuilders. Cohort study; Level of evidence, 3. Medical histories were obtained from 142 experienced male bodybuilders aged 35 to 55 years recruited in the course of 2 studies. Of these men, 88 reported at least 2 years of cumulative lifetime AAS use, and 54 reported no history of AAS use. In men reporting a history of tendon rupture, the circumstances of the injury, prodromal symptoms, concomitant drug or alcohol use, and details of current and lifetime AAS use (if applicable) were recorded. Surgical records were obtained for most participants. Nineteen (22%) of the AAS users, but only 3 (6%) of the nonusers, reported at least 1 lifetime tendon rupture. The hazard ratio for a first ruptured tendon in AAS users versus nonusers was 9.0 (95% CI, 2.5-32.3; P < .001). Several men reported 2 or more independent lifetime tendon ruptures. Interestingly, upper-body tendon ruptures occurred exclusively in the AAS group (15 [17%] AAS users vs 0 nonusers; risk difference, 0.17 [95% CI, 0.09-0.25]; P < .001 [hazard ratio not estimable]), whereas there was no significant difference between users and nonusers in risk for lower-body ruptures (6 [7%] AAS users, 3 [6%] nonusers; hazard ratio, 3.1 [95% CI, 0.7-13.8]; P = .13). Of 31 individual tendon ruptures assessed, only 6 (19%) occurred while weightlifting, with the majority occurring during other sports activities. Eight (26%) ruptures followed prodromal symptoms of nonspecific pain in the region. Virtually all ruptures were treated surgically, with complete or near-complete ultimate restoration of function. AAS abusers, compared with otherwise similar bodybuilders, showed

  4. Inducement of tissue regeneration of harvested hamstring tendons in a rabbit model

    PubMed Central

    Soejima, T.; Murakami, H.; Noguchi, K.; Shiba, N.; Nagata, K.

    2016-01-01

    Objectives The objective of this study was to determine if the use of fascia lata as a tendon regeneration guide (placed into the tendon canal following harvesting the semitendinosus tendon) would improve the incidence of tissue regeneration and prevent fatty degeneration of the semitendinosus muscle. Materials and Methods Bilateral semitendinosus tendons were harvested from rabbits using a tendon stripper. On the inducing graft (IG) side, the tendon canal and semitendinosus tibial attachment site were connected by the fascia lata, which was harvested at the same width as the semitendinosus tendon. On the control side, no special procedures were performed. Two groups of six rabbits were killed at post-operative weeks 4 and 8, respectively. In addition, three healthy rabbits were killed to obtain normal tissue. We evaluated the incidence of tendon tissue regeneration, cross-sectional area of the regenerated tendon tissue and proportion of fatty tissue in the semitendinosus muscle. Results At post-operative week 8, the distal end of the regenerated tissue reached the vicinity of the tibial insertion on the control side in two of six specimens. On the IG side, the regenerated tissue maintained continuity with the tibial insertion in all specimens. The cross-sectional area of the IG side was significantly greater than that of the control side. The proportion of fatty tissue in the semitendinosus muscle on the IG side was comparable with that of the control side, but was significantly greater than that of the normal muscle. Conclusions Tendon tissue regenerated with the fascia lata graft was thicker than naturally occurring regenerated tissue. However, the proportion of fatty tissue in the semitendinosus muscle was greater than that of normal muscle. Cite this article: K. Tabuchi, T. Soejima, H. Murakami, K. Noguchi, N. Shiba, K. Nagata. Inducement of tissue regeneration of harvested hamstring tendons in a rabbit model. Bone Joint Res 2016;5:247–252. DOI: 10

  5. Accumulation of Oxidized LDL in the Tendon Tissues of C57BL/6 or Apolipoprotein E Knock-Out Mice That Consume a High Fat Diet: Potential Impact on Tendon Health

    PubMed Central

    Grewal, Navdeep; Thornton, Gail M.; Behzad, Hayedeh; Sharma, Aishwariya; Lu, Alex; Zhang, Peng; Reid, W. Darlene; Granville, David J.; Scott, Alex

    2014-01-01

    Objective Clinical studies have suggested an association between dyslipidemia and tendon injuries or chronic tendon pain; the mechanisms underlying this association are not yet known. The objectives of this study were (1) to evaluate the impact of a high fat diet on the function of load-bearing tendons and on the distribution in tendons of oxidized low density lipoprotein (oxLDL), and (2) to examine the effect of oxLDL on tendon fibroblast proliferation and gene expression. Methods Gene expression (Mmp2, Tgfb1, Col1a1, Col3a1), fat content (Oil Red O staining), oxLDL levels (immunohistochemistry) and tendon biomechanical properties were examined in mice (C57Bl/6 or ApoE -/-) receiving a standard or a high fat diet. Human tendon fibroblast proliferation and gene expression (COL1A1, COL3A1, MMP2) were examined following oxLDL exposure. Results In both types of mice (C57Bl/6 or ApoE -/-), consumption of a high fat diet led to a marked increase in oxLDL deposition in the load-bearing extracellular matrix of the tendon. The consumption of a high fat diet also reduced the failure stress and load of the patellar tendon in both mouse types, and increased Mmp2 expression. ApoE -/- mice exhibited more pronounced reductions in tendon function than wild-type mice, and decreased expression of Col1a1 compared to wild type mice. Human tendon fibroblasts responded to oxLDL by increasing their proliferation and their mRNA levels of MMP2, while decreasing their mRNA levels for COL1A1 and COL3A1. Conclusion The consumption of a high fat diet resulted in deleterious changes in tendon function, and these changes may be explained in part by the effects of oxLDL, which induced a proliferative, matrix-degrading phenotype in human tenocytes. PMID:25502628

  6. Effects of high loading by eccentric triceps surae training on Achilles tendon properties in humans.

    PubMed

    Geremia, Jeam Marcel; Baroni, Bruno Manfredini; Bobbert, Maarten Frank; Bini, Rodrigo Rico; Lanferdini, Fabio Juner; Vaz, Marco Aurélio

    2018-06-01

    To document the magnitude and time course of human Achilles tendon adaptations (i.e. changes in tendon morphological and mechanical properties) during a 12-week high-load plantar flexion training program. Ultrasound was used to determine Achilles tendon cross-sectional area (CSA), length and elongation as a function of plantar flexion torque during voluntary plantar flexion. Tendon force-elongation and stress-strain relationships were determined before the start of training (pre-training) and after 4 (post-4), 8 (post-8) and 12 (post-12) training weeks. At the end of the training program, maximum isometric force had increased by 49% and tendon CSA by 17%, but tendon length, maximal tendon elongation and maximal strain were unchanged. Hence, tendon stiffness had increased by 82%, and so had Young's modulus, by 86%. Significant changes were first detected at post-4 in stiffness (51% increase) and Young's modulus (87% increase), and at post-8 in CSA (15% increase). Achilles tendon material properties already improved after 4 weeks of high-load training: stiffness increased while CSA remained unchanged. Tendon hypertrophy (increased CSA) was observed after 8 training weeks and contributed to a further increase in Achilles tendon stiffness, but tendon stiffness increases were mostly caused by adaptations in tissue properties.

  7. Structural characterization of CFA/III and Longus type IVb pili from enterotoxigenic Escherichia coli.

    PubMed

    Kolappan, Subramaniapillai; Roos, Justin; Yuen, Alex S W; Pierce, Owen M; Craig, Lisa

    2012-05-01

    The type IV pili are helical filaments found on many Gram-negative pathogenic bacteria, with multiple diverse roles in pathogenesis, including microcolony formation, adhesion, and twitching motility. Many pathogenic enterotoxigenic Escherichia coli (ETEC) isolates express one of two type IV pili belonging to the type IVb subclass: CFA/III or Longus. Here we show a direct correlation between CFA/III expression and ETEC aggregation, suggesting that these pili, like the Vibrio cholerae toxin-coregulated pili (TCP), mediate microcolony formation. We report a 1.26-Å resolution crystal structure of CofA, the major pilin subunit from CFA/III. CofA is very similar in structure to V. cholerae TcpA but possesses a 10-amino-acid insertion that replaces part of the α2-helix with an irregular loop containing a 3(10)-helix. Homology modeling suggests a very similar structure for the Longus LngA pilin. A model for the CFA/III pilus filament was generated using the TCP electron microscopy reconstruction as a template. The unique 3(10)-helix insert fits perfectly within the gap between CofA globular domains. This insert, together with differences in surface-exposed residues, produces a filament that is smoother and more negatively charged than TCP. To explore the specificity of the type IV pilus assembly apparatus, CofA was expressed heterologously in V. cholerae by replacing the tcpA gene with that of cofA within the tcp operon. Although CofA was synthesized and processed by V. cholerae, no CFA/III filaments were detected, suggesting that the components of the type IVb pilus assembly system are highly specific to their pilin substrates.

  8. Mechanical loading stimulates ecto-ATPase activity in human tendon cells.

    PubMed

    Tsuzaki, M; Bynum, D; Almekinders, L; Faber, J; Banes, A J

    2005-09-01

    Response to external stimuli such as mechanical signals is critical for normal function of cells, especially when subjected to repetitive motion. Tenocytes receive mechanical stimuli from the load-bearing matrix as tension, compression, and shear stress during tendon gliding. Overloading a tendon by high strain, shear, or repetitive motion can cause matrix damage. Injury may induce cytokine expression, matrix metalloproteinase (MMP) expression and activation resulting in loss of biomechanical properties. These changes may result in tendinosis or tendinopathy. Alternatively, an immediate effector molecule may exist that acts in a signal-dampening pathway. Adenosine 5'-triphosphate (ATP) is a candidate signal blocker of mechanical stimuli. ATP suppresses load-inducible inflammatory genes in human tendon cells in vitro. ATP and other extracellular nucleotide signaling are regulated efficiently by two distinct mechanisms: purinoceptors via specific receptor-ligand binding and ecto-nucleotidases via the hydrolysis of specific nucleotide substrates. ATP is released from tendon cells by mechanical loading or by uridine 5'-triphosphate (UTP) stimulation. We hypothesized that mechanical loading might stimulate ecto-ATPase activity. Human tendon cells of surface epitenon (TSC) and internal compartment (TIF) were cyclically stretched (1 Hz, 0.035 strain, 2 h) with or without ATP. Aliquots of the supernatant fluids were collected at various time points, and ATP concentration (ATP) was determined by a luciferin-luciferase bioluminescence assay. Total RNA was isolated from TSC and TIF (three patients) and mRNA expression for ecto-nucleotidase was analyzed by RT-PCR. Human tendon cells secreted ATP in vitro (0.5-1 nM). Exogenous ATP was hydrolyzed within minutes. Mechanical load stimulated ATPase activity. ATP was hydrolyzed in mechanically loaded cultures at a significantly greater rate compared to no load controls. Tenocytes (TSC and TIF) expressed ecto-nucleotidase mRNA (ENTPD

  9. Repair of Double Head Pectoralis Major Tendon Avulsion into its Native Footprint Using Bi-cortical EndoButtons and Tendon Sliding Technique.

    PubMed

    Prabhu, Jagadish; Faqi, Mohammed Khalid; Alkhalifa, Fahad; Tayara, Bader Kamal; Awad, Rashad Khamis

    2017-01-01

    Injuries to the pectoralis major muscle are relatively infrequent. The mechanism of injury is usually an eccentric shortening of the pectoralis major under heavy load, such as when performing a bench press exercise. We report a case that presented to us with a history of sudden pain in the left pectoral region while doing heavy bench press exercise. The patient sustained a type III D pectoralis muscle -tendon avulsion. Surgical repair was done through a bi-cortical tendon sliding technique using two cortical buttons. In this article we describe our modifications to the previously described surgical technique for the pectoralis major tendon repair using the EndoButton and tension - slide technique, aiming to overcome the possible complications.

  10. US appearance of partial-thickness supraspinatus tendon tears: Application of the string theory. Pictorial essay.

    PubMed

    Guerini, H; Fermand, M; Godefroy, D; Feydy, A; Chevrot, A; Morvan, G; Gault, N; Drapé, J L

    2012-02-01

    The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination.A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT).

  11. The biomechanical effects of limb lengthening and botulinum toxin type A on rabbit tendon.

    PubMed

    Olabisi, Ronke M; Best, Thomas M; Hurschler, Christof; Vanderby, Ray; Noonan, Kenneth J

    2010-12-01

    Numerous studies have examined the effects of distraction osteogenesis (DO) on bone, but relatively fewer have explored muscle adaptation, and even less have addressed the concomitant alterations that occur in the tendon. The purpose herein was to characterize the biomechanical properties of normal and elongated rabbit (N = 20) tendons with and without prophylactic botulinum toxin type A (BTX-A) treatment. Elastic and viscoelastic properties of Achilles and Tibialis anterior (TA) tendons were evaluated through pull to failure and stress relaxation tests. All TA tendons displayed nonlinear viscoelastic responses that were strain dependent. A power law formulation was used to model tendon viscoelastic responses and tendon elastic responses were fit with a microstructural model. Distraction-elongated tendons displayed increases in compliance and stress relaxation rates over undistracted tendons; BTX-A administration offset this result. The elastic moduli of distraction-lengthened TA tendons were diminished (p = 0.010) when distraction was combined with gastrocnemius (GA) BTX-A administration, elastic moduli were further decreased (p = 0.004) and distraction following TA BTX-A administration resulted in TA tendons with moduli not different from contralateral control (p > 0.05). Compared to contralateral control, distraction and GA BTX-A administration displayed shortened toe regions, (p = 0.031 and 0.038, respectively), while tendons receiving BTX-A in the TA had no differences in the toe region (p > 0.05). Ultimate tensile stress was unaltered by DO, but stress at the transition from the toe to the linear region of the stress-stretch curve was diminished in all distraction-elongated TA tendons (p < 0.05). The data suggest that prophylactic BTX-A treatment to the TA protects some tendon biomechanical properties. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. [Distal soft-tissue procedure in hallux valgus deformity].

    PubMed

    Arbab, D; Wingenfeld, C; Frank, D; Bouillon, B; König, D P

    2016-04-01

    Distal, lateral soft tissue release to restore mediolateral balance of the first metatarsophalangeal (MTP) joint in hallux valgus deformity. Incision of the adductor hallucis tendon from the fibular sesamoid, the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament. Hallux valgus deformities or recurrent hallux valgus deformities with an incongruent MTP joint. General medical contraindications to surgical interventions. Painful stiffness of the MTP joint, osteonecrosis, congruent joint. Relative contraindications: connective tissue diseases (Marfan syndrome, Ehler-Danlos syndrome). Longitudinal, dorsal incision in the first intermetatarsal web space between the first and second MTP joint. Blunt dissection and identification of the adductor hallucis tendon. Release of the adductor tendon from the fibular sesamoid. Incision of the lateral capsule, the lateral collateral ligament, and the lateral metatarsosesamoid ligament. Postoperative management depends on bony correction. In joint-preserving procedures, dressing for 3 weeks in corrected position. Subsequently hallux valgus orthosis at night and a toe spreader for a further 3 months. Passive mobilization of the first MTP joint. Postoperative weight-bearing according to the osteotomy. A total of 31 patients with isolated hallux valgus deformity underwent surgery with a Chevron and Akin osteotomy and a distal medial and lateral soft tissue balancing. The mean preoperative intermetatarsal (IMA) angle was 12.3° (range 11-15°); the hallux valgus (HV) angle was 28.2° (25-36°). The mean follow-up was 16.4 months (range 12-22 months). The mean postoperative IMA correction ranged between 2 and 7° (mean 5.2°); the mean HV correction was 15.5° (range 9-21°). In all, 29 patients (93%) were satisfied or very satisfied with the postoperative outcome, while 2 patients (7%) were not satisfied due to one delayed wound healing and one recurrent hallux valgus deformity. There were no

  13. Tension Regulation at the Suture Lines for Repair of Neglected Achilles Tendon Laceration.

    PubMed

    Massoud, Elsayed Ibraheem Elsayed

    2017-03-01

    Operative intervention is the preferred option for management of the neglected laceration of the Achilles tendon. However, the commonly used techniques rarely follow the principles of the regenerative medicine for the restoration of the lost tissue. This study postulated that incorporation of the autogenous tendon graft would properly progress when the interplay between mechanical loading and healing phases was correctly applied. A prospective study included 15 patients who were treated for neglected Achilles tendon laceration using the technique of lengthening of the proximal tendon stump. An absorbable reinforcement suture was used for control of the mechanical environment at the suture lines. By an average 5 years of the prospective follow-up, all the repaired tendons had restored continuity and length. The calf circumference equalized to the uninjured side in 12 patients. However, 3 patients had calf atrophy but they improved compared to the preoperative measurements. Sonogram confirmed the restoration of the normal thickness and the gliding characteristics of the repaired tendon. The technique restored continuity and tension of the repaired tendon, preserved the calf circumference, and prevented peritendinous adhesions. The absorbable reinforcement suture spontaneously allowed for the mechanical loading of the grafted tendon. Level IV, case series.

  14. A review on animal models and treatments for the reconstruction of Achilles and flexor tendons.

    PubMed

    Bottagisio, Marta; Lovati, Arianna B

    2017-03-01

    Tendon is a connective tissue mainly composed of collagen fibers with peculiar mechanical properties essential to functional movements. The increasing incidence of tendon traumatic injuries and ruptures-associated or not with the loss of tissue-falls on the growing interest in the field of tissue engineering and regenerative medicine. The use of animal models is mandatory to deepen the knowledge of the tendon healing response to severe damages or acute transections. Thus, the selection of preclinical models is crucial to ensure a successful translation of effective and safe innovative treatments to the clinical practice. The current review is focused on animal models of tendon ruptures and lacerations or defective injuries with large tissue loss that require surgical approaches or grafting procedures. Data published between 2000 and 2016 were examined. The analyzed articles were compiled from Pub Med-NCBI using search terms, including animal model(s) AND tendon augmentation OR tendon substitute(s) OR tendon substitution OR tendon replacement OR tendon graft(s) OR tendon defect(s) OR tendon rupture(s). This article presents the existing preclinical models - considering their advantages and disadvantages-in which translational progresses have been made by using bioactive sutures or tissue engineering that combines biomaterials with cells and growth factors to efficiently treat transections or large defects of Achilles and flexor tendons.

  15. Fibrocartilage in tendons and ligaments — an adaptation to compressive load

    PubMed Central

    BENJAMIN, M.; RALPHS, J. R.

    1998-01-01

    Where tendons and ligaments are subject to compression, they are frequently fibrocartilaginous. This occurs at 2 principal sites: where tendons (and sometimes ligaments) wrap around bony or fibrous pulleys, and in the region where they attach to bone, i.e. at their entheses. Wrap-around tendons are most characteristic of the limbs and are commonly wider at their point of bony contact so that the pressure is reduced. The most fibrocartilaginous tendons are heavily loaded and permanently bent around their pulleys. There is often pronounced interweaving of collagen fibres that prevents the tendons from splaying apart under compression. The fibrocartilage can be located within fascicles, or in endo- or epitenon (where it may protect blood vessels from compression or allow fascicles to slide). Fibrocartilage cells are commonly packed with intermediate filaments which could be involved in transducing mechanical load. The ECM often contains aggrecan which allows the tendon to imbibe water and withstand compression. Type II collagen may also be present, particularly in tendons that are heavily loaded. Fibrocartilage is a dynamic tissue that disappears when the tendons are rerouted surgically and can be maintained in vitro when discs of tendon are compressed. Finite element analyses provide a good correlation between its distribution and levels of compressive stress, but at some locations fibrocartilage is a sign of pathology. Enthesis fibrocartilage is most typical of tendons or ligaments that attach to the epiphyses of long bones where it may also be accompanied by sesamoid and periosteal fibrocartilages. It is characteristic of sites where the angle of attachment changes throughout the range of joint movement and it reduces wear and tear by dissipating stress concentration at the bony interface. There is a good correlation between the distribution of fibrocartilage within an enthesis and the levels of compressive stress. The complex interlocking between calcified

  16. Faster Movement Speed Results in Greater Tendon Strain during the Loaded Squat Exercise

    PubMed Central

    Earp, Jacob E.; Newton, Robert U.; Cormie, Prue; Blazevich, Anthony J.

    2016-01-01

    Introduction: Tendon dynamics influence movement performance and provide the stimulus for long-term tendon adaptation. As tendon strain increases with load magnitude and decreases with loading rate, changes in movement speed during exercise should influence tendon strain. Methods: Ten resistance-trained men [squat one repetition maximum (1RM) to body mass ratio: 1.65 ± 0.12] performed parallel-depth back squat lifts with 60% of 1RM load at three different speeds: slow fixed-tempo (TS: 2-s eccentric, 1-s pause, 2-s concentric), volitional-speed without a pause (VS) and maximum-speed jump (JS). In each condition joint kinetics, quadriceps tendon length (LT), patellar tendon force (FT), and rate of force development (RFDT) were estimated using integrated ultrasonography, motion-capture, and force platform recordings. Results: Peak LT, FT, and RFDT were greater in JS than TS (p < 0.05), however no differences were observed between VS and TS. Thus, moving at faster speeds resulted in both greater tendon stress and strain despite an increased RFDT, as would be predicted of an elastic, but not a viscous, structure. Temporal comparisons showed that LT was greater in TS than JS during the early eccentric phase (10–14% movement duration) where peak RFDT occurred, demonstrating that the tendon's viscous properties predominated during initial eccentric loading. However, during the concentric phase (61–70 and 76–83% movement duration) differing FT and similar RFDT between conditions allowed for the tendon's elastic properties to predominate such that peak tendon strain was greater in JS than TS. Conclusions: Based on our current understanding, there may be an additional mechanical stimulus for tendon adaptation when performing large range-of-motion isoinertial exercises at faster movement speeds. PMID:27630574

  17. Use of three-dimensional finite element models of the lateral ankle ligaments to evaluate three surgical techniques

    PubMed Central

    Wang, Cheng-Wei; Muheremu, Aikeremujiang; Bai, Jing-Ping

    2017-01-01

    Objective To compare three surgical techniques for lateral ankle ligament reconstruction using finite element (FE) models. Methods A three-dimensional FE model of the left foot of a healthy volunteer and lateral collateral ligament injury models were developed. Three tendons [one-half of the autologous peroneus longus tendon (PLT), one-half of the peroneus brevis tendon (PBT), and an allogeneic tendon] were used for lateral collateral ligament reconstruction. The ankle varus stress and anterior drawer tests were performed to compare the three surgical techniques. Results The ankle varus stress test showed that the equivalent stresses of the anterior talofibular ligament (ATFL) (84.00 MPa) and calcaneofibular ligament (CFL) (27.01 MPa) were lower in allogeneic tendon reconstruction than in the other two techniques but similar to those of normal individuals (138.48 and 25.90 MPa, respectively). The anterior drawer test showed that the equivalent stresses of the ATFL and CFL in autologous PLT reconstruction (31.31 and 28.60 MPa, respectively) and PBT reconstruction (31.47 and 29.07 MPa, respectively) were lower than those in allogeneic tendon reconstruction (57.32 and 52.20 MPa, respectively). Conclusions The allogeneic tendon reconstruction outcome was similar to normal individuals. Allogeneic tendon reconstruction may be superior for lateral ankle ligament reconstruction without considering its complications. PMID:29239256

  18. Therapeutic Effects of Doxycycline on the Quality of Repaired and Unrepaired Achilles Tendons.

    PubMed

    Nguyen, Quynhhoa T; Norelli, Jolanta B; Graver, Adam; Ekstein, Charles; Schwartz, Johnathan; Chowdhury, Farzana; Drakos, Mark C; Grande, Daniel A; Chahine, Nadeen O

    2017-10-01

    Achilles tendon tears are devastating injuries, especially to athletes. Elevated matrix metalloproteinase (MMP) activity after a tendon injury has been associated with deterioration of the collagen network and can be inhibited with doxycycline (Doxy). Daily oral administration of Doxy will enhance the histological, molecular, and biomechanical quality of transected Achilles tendons. Additionally, suture repair will further enhance the quality of repaired tendons. Controlled laboratory study. Randomized unilateral Achilles tendon transection was performed in 288 adult male Sprague-Dawley rats. The injured tendons were either unrepaired (groups 1 and 2) or surgically repaired (groups 3 and 4). Animals from groups 2 and 4 received Doxy daily through oral gavage, and animals from groups 1 and 3 served as controls (no Doxy). Tendons were harvested at 1.5, 3, 6, and 9 weeks after the injury (n = 18 per group and time point). The quality of tendon repair was evaluated based on the histological grading score, collagen fiber orientation, gene expression, and biomechanical properties. In surgically repaired samples, Doxy enhanced the quality of tendon repair compared with no Doxy ( P = .0014). Doxy had a significant effect on collagen fiber dispersion, but not principal fiber angle. There was a significant effect of time on the gene expression of MMP-3, MMP-9 and TIMP1, and Doxy significantly decreased MMP-3 expression at 9 weeks. Doxy treatment with surgical repair increased the dynamic modulus at 6 weeks but not at 9 weeks after the injury ( P < .001). Doxy also increased the equilibrium modulus and decreased creep strain irrespective of the repair group. Doxy did not have a significant effect on the histology or biomechanics of unrepaired tendons. The findings indicate that daily oral administration of Doxy accelerated matrix remodeling and the dynamic and equilibrium biomechanics of surgically repaired Achilles tendons, although such enhancements were most evident at the

  19. A systematic review of tibialis anterior tendon rupture treatments and outcomes.

    PubMed

    Christman-Skieller, Claudia; Merz, Michael K; Tansey, Joseph P

    2015-04-01

    Tibialis anterior (TA) tendon rupture is a relatively rare injury that has been documented primarily in case reports. This article is the first large systematic review of the literature on treatment techniques for subcutaneous rupture of TA tendons. Studies for review were identified through a PubMed search. Eligible studies involved cases of closed tendon rupture. Of the 87 cases in the study, 72 were treated with surgery, 15 with conservative measures. Mean age was 63.9 years (surgery group) and 72.4 years (conservative treatment group). Primary repair was used most often for newer injuries, autograft most often for older injuries. Operative repair of subcutaneous TA tendon rupture leads to successful outcomes in many patients. A surgeon who is deciding which operative technique to use for a patient should consider the age of the injury and the findings of intraoperative assessment for tendon necrosis.

  20. Eccentric exercise: acute and chronic effects on healthy and diseased tendons.

    PubMed

    Kjaer, Michael; Heinemeier, Katja M

    2014-06-01

    Eccentric exercise can influence tendon mechanical properties and matrix protein synthesis. mRNA for collagen and regulatory factors thereof are upregulated in animal tendons, independent of muscular contraction type, supporting the view that tendon, compared with skeletal muscle, is less sensitive to differences in type and/or amount of mechanical stimulus with regard to expression of collagen, regulatory factors for collagen, and cross-link regulators. In overused (tendinopathic) human tendon, eccentric exercise training has a beneficial effect, but the mechanism by which this is elicited is unknown, and slow concentric loading appears to have similar beneficial effects. It may be that tendinopathic regions, as long as they are subjected to a certain magnitude of load at a slow speed, independent of whether this is eccentric or concentric in nature, can reestablish their normal tendon fibril alignment and cell morphology. Copyright © 2014 the American Physiological Society.

  1. Medial versus lateral supraspinatus tendon properties: implications for double-row rotator cuff repair.

    PubMed

    Wang, Vincent M; Wang, Fan Chia; McNickle, Allison G; Friel, Nicole A; Yanke, Adam B; Chubinskaya, Susan; Romeo, Anthony A; Verma, Nikhil N; Cole, Brian J

    2010-12-01

    Rotator cuff repair retear rates range from 25% to 90%, necessitating methods to improve repair strength. Although numerous laboratory studies have compared single-row with double-row fixation properties, little is known regarding regional (ie, medial vs lateral) suture retention properties in intact and torn tendons. A torn supraspinatus tendon will have reduced suture retention properties on the lateral aspect of the tendon compared with the more medial musculotendinous junction. Controlled laboratory study. Human supraspinatus tendons (torn and intact) were randomly assigned for suture retention mechanical testing, ultrastructural collagen fibril analysis, or histologic testing after suture pullout testing. For biomechanical evaluation, sutures were placed either at the musculotendinous junction (medial) or 10 mm from the free margin (lateral), and tendons were elongated to failure. Collagen fibril assessments were performed using transmission electron microscopy. Intact tendons showed no regional differences with respect to suture retention properties. In contrast, among torn tendons, the medial region exhibited significantly higher stiffness and work values relative to the lateral region. For the lateral region, work to 10-mm displacement (1592 ± 261 N-mm) and maximum load (265 ± 44 N) for intact tendons were significantly higher (P < .05) than that of torn tendons (1086 ± 388 N-mm and 177 ± 71 N, respectively). For medial suture placement, maximum load, stiffness, and work of intact and torn tendons were similar (P > .05). Regression analyses for the intact and torn groups revealed generally low correlations between donor age and the 3 biomechanical indices. For both intact and torn tendons, the mean fibril diameter and area density were greater in the medial region relative to the lateral (P ≤ .05). In the lateral tendon, but not the medial region, torn specimens showed a significantly lower fibril area fraction (48.3% ± 3.8%) than intact specimens

  2. The intersection syndrome: Ultrasound findings and their diagnostic value

    PubMed Central

    Montechiarello, S.; Miozzi, F.; D’Ambrosio, I.; Giovagnorio, F.

    2010-01-01

    Introduction The intersection syndrome is a well-known overuse syndrome of the distal forearm. It is characterized by noninfectious, inflammatory changes involving the area of intersection of the first (abductor pollicis longus and extensor pollicis brevis) and second (extensor carpi radialis longus and extensor carpi radialis brevis) extensor compartments in the dorsoradial aspect of the distal forearm. Imaging modalities used to diagnosis this syndrome include ultrasonography (US) and magnetic resonance imaging. The purpose of this report is to describe typical US findings in the intersection syndrome and to demonstrate the diagnostic value of this approach. Materials and methods We reviewed US findings in 4 patients (mean age 40 years) referred to our staff for symptoms suggestive of the intersection syndrome (pain, swelling, erythema, and edema of the wrist). Results In all 4 cases, the US examination revealed peritendinous edema and synovial fluid within the tendon sheaths at the intersection between the first and the second dorsal extensor tendon compartments. Discussion Our experience shows that the intersection syndrome is associated with typical signs on US. This imaging modality can be considered a reliable tool for diagnosing this syndrome and may eliminate the need for other more expensive tests. PMID:23396515

  3. [Isokinetic assessment with two years follow-up of anterior cruciate ligament reconstruction with patellar tendon or hamstring tendons].

    PubMed

    Condouret, J; Cohn, J; Ferret, J-M; Lemonsu, A; Vasconcelos, W; Dejour, D; Potel, J-F

    2008-12-01

    This retrospective multicentric study was designed to assess the outcome of quadriceps and hamstrings muscles two years after Anterior Cruciate Ligament (ACL) reconstruction and compare muscles recovery depending on the type of graft and individual variables like age, gender, level of sport, but also in terms of discomfort, pain and functional score. The results focused on the subjective and objective IKDC scores, SF36, the existence or not of subjective disorders and their location. The review included isokinetic muscle tests concentric and eccentric extensors/flexors but also internal rotators/external rotators with analysis of mean work and mean power. One hundred and twenty-seven patients were included with an average age 29 years (+/-10). They all had an ACL reconstruction with patellar tendon or hamstring tendon with single or double bundles. In the serie, the average muscles deficit at two years was 10% for the flexors and extensors but with a significant dispersion. Significant differences were not noted in the mean values of all parameters in term of sex or age (over 30 years or not), neither the type of sport, nor of clinical assessment (Class A and B of objective IKDC score), nor the existence of anterior knee pain. There was a relationship between the level of extensor or flexor recovery and the quality of functional results with minimal muscle deficits close to 5% if the IKDC score was over 90 and deficits falling to 15% in the group with IKDC score less than 90. The type of reconstruction (patellar tendon versus hamstrings) had an influence on the muscle deficit. For extensors, the recovery was the same in the two groups, more than 90% at two years and the distribution of these two populations by level of deficit was quite the same. For flexors, residual deficits were significantly higher in the hamstrings group on the three studied parameters whatever the speed and the type of contraction (concentric or eccentric) with an average deficit of 14 to 18

  4. Mineralization can be an incidental ultrasonographic finding in equine tendons and ligaments.

    PubMed

    O'Brien, Etienne J O; Smith, Roger K W

    2018-05-18

    Tendon/ligament mineralization is recognized in horses but information regarding its clinical significance is limited. The aims of this observational study were to report the structures most commonly affected by ultrasonographically detectable mineralization and, for these, determine frequency of diagnosis and key clinical features. Cases presented at our hospital in April 1999-April 2013 and September 2014-November 2015 were included: a total of 27 horses (22 retrospective, five prospective). Mineralizations were most common in deep digital flexor tendons (10) and suspensory ligament branches (eight), representing 10% and 7% (estimated), respectively, of horses diagnosed with injuries to these structures during the study. Two deep digital flexor tendon and three suspensory ligament branch cases showed bilateral mineralization. Deep digital flexor tendon mineralization was restricted to the digital flexor tendon sheath, most commonly in the proximal sheath (±sesamoidean canal), and seven of 10 cases involved hindlimbs. Suspensory ligament branch mineralization was visible in the same ultrasound window as the proximal sesamoid bones in 10/11 limbs and six of eight cases involved forelimbs. Previous corticosteroid medication was a feature of one deep digital flexor tendon and one suspensory ligament branch case. Mineralization was associated with lameness in some but not all limbs. Mineralized foci within the deep digital flexor tendon preceded hypoechoic lesion formation in two limbs. Of the cases with deep digital flexor tendon or suspensory ligament branch injury only, one of three and two of three cases, respectively, became sound. Findings indicated that tendon/ligament mineralization can be associated with lameness in some horses, but can also be an incidental finding. © 2018 American College of Veterinary Radiology.

  5. Patellar tendon healing with platelet-rich plasma: a prospective randomized controlled trial.

    PubMed

    de Almeida, Adriano Marques; Demange, Marco Kawamura; Sobrado, Marcel Faraco; Rodrigues, Marcelo Bordalo; Pedrinelli, André; Hernandez, Arnaldo José

    2012-06-01

    The patellar tendon has limited ability to heal after harvesting its central third. Platelet-rich plasma (PRP) could improve patellar tendon healing. Adding PRP to the patellar tendon harvest site would improve donor site healing and improve clinical outcome at 6 months after anterior cruciate ligament (ACL) reconstruction with a patellar tendon graft. Randomized controlled trial; Level of evidence, 1. Twenty-seven patients were randomly divided to receive (n = 12) or not receive (n = 15) PRP in the patellar tendon harvest site during ACL reconstruction. The primary outcome was magnetic resonance imaging (MRI) assessment of patellar tendon healing (gap area) after 6 months. Secondary outcomes were questionnaires and isokinetic testing of ACL reconstruction with a patellar tendon graft comparing both groups. Patellar tendon gap area was significantly smaller in the PRP group (4.9 ± 5.3 mm(2); 95% confidence interval [CI], 1.1-8.8) than in the control group (9.4 ± 4.4 mm(2); 95% CI, 6.6-12.2; P = .046). Visual analog scale score for pain was lower in the PRP group immediately postoperatively (3.8 ± 1.0; 95% CI, 3.18-4.49) than in the control group (5.1 ± 1.4; 95% CI, 4.24-5.90; P = .02). There were no differences after 6 months in questionnaire and isokinetic testing results comparing both groups. We showed that PRP had a positive effect on patellar tendon harvest site healing on MRI after 6 months and also reduced pain in the immediate postoperative period. Questionnaire and isokinetic testing results were not different between the groups at 6 months.

  6. Spontaneous Achilles tendon rupture in alkaptonuria

    PubMed Central

    Alajoulin, Omar A.; Alsbou, Mohammed S.; Ja’afreh, Somayya O.; Kalbouneh, Heba M.

    2015-01-01

    Alkaptonuria (AKU) is a rare inborn metabolic disease characterized by accumulation of homogentisic acid (HGA). Excretion of HGA in urine causes darkening of urine and its deposition in connective tissues causes dark pigmentation (ochronosis), early degeneration of articular cartilage, weakening of the tendons, and subsequent rupture. In this case report, we present a rare case of a patient presented with unilateral spontaneous rupture of Achilles tendon due to AKU. The patient developed most of the orthopedic manifestations of the disease earlier than typical presentations. Alkaptonuria patients should avoid strenuous exercises and foot straining especially in patients developing early orthopedic manifestations. PMID:26620992

  7. Spontaneous Achilles tendon rupture in alkaptonuria.

    PubMed

    Alajoulin, Omar A; Alsbou, Mohammed S; Ja'afreh, Somayya O; Kalbouneh, Heba M

    2015-12-01

    Alkaptonuria (AKU) is a rare inborn metabolic disease characterized by accumulation of homogentisic acid (HGA). Excretion of HGA in urine causes darkening of urine and its deposition in connective tissues causes dark pigmentation (ochronosis), early degeneration of articular cartilage, weakening of the tendons, and subsequent rupture. In this case report, we present a rare case of a patient presented with unilateral spontaneous rupture of Achilles tendon due to AKU. The patient developed most of the orthopedic manifestations of the disease earlier than typical presentations. Alkaptonuria patients should avoid strenuous exercises and foot straining especially in patients developing early orthopedic manifestations.

  8. [Achilles tendon xanthoma imaging on ultrasound and magnetic resonance imaging].

    PubMed

    Fernandes, Eloy de Ávila; Santos, Eduardo Henrique Sena; Tucunduva, Tatiana Cardoso de Mello; Ferrari, Antonio J L; Fernandes, Artur da Rocha Correa

    2015-01-01

    The Achilles tendon xanthoma is a rare disease and has a high association with primary hyperlipidemia. An early diagnosis is essential to start treatment and change the disease course. Imaging exams can enhance diagnosis. This study reports the case of a 60-year-old man having painless nodules on his elbows and Achilles tendons without typical gout crisis, followed in the microcrystalline disease clinic of Unifesp for diagnostic workup. Laboratory tests obtained showed dyslipidemia. The ultrasound (US) showed a diffuse Achilles tendon thickening with hypoechoic areas. Magnetic resonance imaging (MRI) showed a diffuse tendon thickening with intermediate signal areas, and a reticulate pattern within. Imaging studies showed relevant aspects to diagnose a xanthoma, thus helping in the differential diagnosis. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

  9. Obesity/Type II diabetes alters macrophage polarization resulting in a fibrotic tendon healing response

    PubMed Central

    Ackerman, Jessica E.; Geary, Michael B.; Orner, Caitlin A.; Bawany, Fatima

    2017-01-01

    Type II Diabetes (T2DM) dramatically impairs the tendon healing response, resulting in decreased collagen organization and mechanics relative to non-diabetic tendons. Despite this burden, there remains a paucity of information regarding the mechanisms that govern impaired healing of diabetic tendons. Mice were placed on either a high fat diet (T2DM) or low fat diet (lean) and underwent flexor tendon transection and repair surgery. Healing was assessed via mechanical testing, histology and changes in gene expression associated with collagen synthesis, matrix remodeling, and macrophage polarization. Obese/diabetic tendons healed with increased scar formation and impaired mechanical properties. Consistent with this, prolonged and excess expression of extracellular matrix (ECM) components were observed in obese/T2DM tendons. Macrophages are involved in both inflammatory and matrix deposition processes during healing. Obese/T2DM tendons healed with increased expression of markers of pro-inflammatory M1 macrophages, and elevated and prolonged expression of M2 macrophages markers that are involved in ECM deposition. Here we demonstrate that tendons from obese/diabetic mice heal with increased scar formation and increased M2 polarization, identifying excess M2 macrophage activity and matrix synthesis as a potential mechanism of the fibrotic healing phenotype observed in T2DM tendons, and as such a potential target to improve tendon healing in T2DM. PMID:28686669

  10. Early changes in Achilles tendon behaviour in vivo following downhill backwards walking.

    PubMed

    Joseph, C W; Bradshaw, E J; Furness, T P; Kemp, J; Clark, R A

    2016-01-01

    Downhill backwards walking causes repeated, cyclical loading of the muscle-tendon unit. The effect this type of repeated loading has on the mechanical behaviour of the Achilles tendon is presently unknown. This study aimed to investigate the biomechanical response of the Achilles tendon aponeurosis complex following a downhill backwards walking protocol. Twenty active males (age: 22.3 ± 3.0 years; mass: 74.7 ± 5.6 kg; height: 1.8 ± 0.7 m) performed 60 min of downhill (8.5°), backwards walking on a treadmill at -0.67 m · s(-1). Data were collected before, immediately post, and 24-, 48- and 168-h post-downhill backwards walking. Achilles tendon aponeurosis elongation, strain and stiffness were measured using ultrasonography. Muscle force decreased immediately post-downhill backward walking (P = 0.019). There were increases in Achilles tendon aponeurosis stiffness at 24-h post-downhill backward walking (307 ± 179.6 N · mm(-1), P = 0.004), and decreases in Achilles tendon aponeurosis strain during maximum voluntary contraction at 24 (3.8 ± 1.7%, P = 0.008) and 48 h (3.9 ± 1.8%, P = 0.002) post. Repeated cyclical loading of downhill backwards walking affects the behaviour of the muscle-tendon unit, most likely by altering muscle compliance, and these changes result in tendon stiffness increases.

  11. Effects of running on human Achilles tendon length-tension properties in the free and gastrocnemius components.

    PubMed

    Lichtwark, Glen A; Cresswell, Andrew G; Newsham-West, Richard J

    2013-12-01

    The elastic properties of the human Achilles tendon are important for locomotion; however, in vitro tests suggest that repeated cyclic contractions lead to tendon fatigue - an increase in length in response to stress applied. In vivo experiments have not, however, demonstrated mechanical fatigue in the Achilles tendon, possibly due to the limitations of using two-dimensional ultrasound imaging to assess tendon strain. This study used freehand three-dimensional ultrasound (3DUS) to determine whether the free Achilles tendon (calcaneus to soleus) or the gastrocnemius tendon (calcaneus to gastrocnemius) demonstrated tendon fatigue after running exercise. Participants (N=9) underwent 3DUS scans of the Achilles tendon during isometric contractions at four ankle torque levels (passive, and 14, 42 and 70 N m) before and after a 5 km run at a self-selected pace (10-14 km h(-1)). Running had a significant main effect on the length of the free Achilles tendon (P<0.01) with a small increase in length across the torque range. However, the mean lengthening effect was small (<1%) and was not accompanied by a change in free tendon stiffness. There was no significant change in the length of the gastrocnemius tendon or the free tendon cross-sectional area. While the free tendon was shown to lengthen, the lack of change in stiffness suggests the tendon exhibited mechanical creep rather than fatigue. These effects were much smaller than those predicted from in vitro experiments, possibly due to the different loading profile encountered and the ability of the tendon to repair in vivo.

  12. Modulation of the Fibularis Longus Hoffmann Reflex and Postural Instability Associated With Chronic Ankle Instability

    PubMed Central

    Kim, Kyung-Min; Hart, Joseph M.; Saliba, Susan A.; Hertel, Jay

    2016-01-01

    Context: Individuals with chronic ankle instability (CAI) present with decreased modulation of the Hoffmann reflex (H-reflex) from a simple to a more challenging task. The neural alteration is associated with impaired postural control, but the relationship has not been investigated in individuals with CAI. Objective: To determine differences in H-reflex modulation and postural control between individuals with or without CAI and to identify if they are correlated in individuals with CAI. Design: Descriptive laboratory study. Setting: Laboratory. Patients or Other Participants: A total of 15 volunteers with CAI (9 males, 6 females; age = 22.6 ± 5.8 years, height = 174.7 ± 8.1 cm, mass = 74.9 ± 12.8 kg) and 15 healthy sex-matched volunteers serving as controls (9 males, 6 females; age = 23.8 ± 5.8 years, height = 171.9 ± 9.9 cm, mass = 68.9 ± 15.5 kg) participated. Intervention(s): Maximum H-reflex (Hmax) and motor wave (Mmax) from the soleus and fibularis longus were recorded while participants lay prone and then stood in unipedal stance. We assessed postural tasks of unipedal stance with participants' eyes closed for 10 seconds using a forceplate. Main Outcome Measure(s): We normalized Hmax to Mmax to obtain Hmax : Mmax ratios for the 2 positions. For each muscle, H-reflex modulation was quantified using the percentage change scores in Hmax : Mmax ratios calculated from prone position to unipedal stance. Center-of-pressure data were used to compute 4 time-to-boundary variables. Separate independent-samples t tests were performed to determine group differences. Pearson product moment correlation coefficients were calculated between the modulation and balance measures in the CAI group. Results: The CAI group presented less H-reflex modulation in the soleus (t26 = −3.77, P = .001) and fibularis longus (t25 = −2.59, P = .02). The mean of the time-to-boundary minima in the anteroposterior direction was lower in the CAI group (t28 = −2.06, P = .048

  13. Quantification of Internal Stress-Strain Fields in Human Tendon: Unraveling the Mechanisms that Underlie Regional Tendon Adaptations and Mal-Adaptations to Mechanical Loading and the Effectiveness of Therapeutic Eccentric Exercise

    PubMed Central

    Maganaris, Constantinos N.; Chatzistergos, Panagiotis; Reeves, Neil D.; Narici, Marco V.

    2017-01-01

    By virtue of their anatomical location between muscles and bones, tendons make it possible to transform contractile force to joint rotation and locomotion. However, tendons do not behave as rigid links, but exhibit viscoelastic tensile properties, thereby affecting the length and contractile force in the in-series muscle, but also storing and releasing elastic stain energy as some tendons are stretched and recoiled in a cyclic manner during locomotion. In the late 90s, advancements were made in the application of ultrasound scanning that allowed quantifying the tensile deformability and mechanical properties of human tendons in vivo. Since then, the main principles of the ultrasound-based method have been applied by numerous research groups throughout the world and showed that tendons increase their tensile stiffness in response to exercise training and chronic mechanical loading, in general, by increasing their size and improving their intrinsic material. It is often assumed that these changes occur homogenously, in the entire body of the tendon, but recent findings indicate that the adaptations may in fact take place in some but not all tendon regions. The present review focuses on these regional adaptability features and highlights two paradigms where they are particularly evident: (a) Chronic mechanical loading in healthy tendons, and (b) tendinopathy. In the former loading paradigm, local tendon adaptations indicate that certain regions may “see,” and therefore adapt to, increased levels of stress. In the latter paradigm, local pathological features indicate that certain tendon regions may be “stress-shielded” and degenerate over time. Eccentric exercise protocols have successfully been used in the management of tendinopathy, without much sound understanding of the mechanisms underpinning their effectiveness. For insertional tendinopathy, in particular, it is possible that the effectiveness of a loading/rehabilitation protocol depends on the topography

  14. Genetic Factors in Tendon Injury: A Systematic Review of the Literature

    PubMed Central

    Vaughn, Natalie H.; Stepanyan, Hayk; Gallo, Robert A.; Dhawan, Aman

    2017-01-01

    Background: Tendon injury such as tendinopathy or rupture is common and has multiple etiologies, including both intrinsic and extrinsic factors. The genetic influence on susceptibility to tendon injury is not well understood. Purpose: To analyze the published literature regarding genetic factors associated with tendon injury. Study Design: Systematic review; Level of evidence, 3. Methods: A systematic review of published literature was performed in concordance with the Preferred Reporting Items of Systematic Reviews and Meta-analysis (PRISMA) guidelines to identify current evidence for genetic predisposition to tendon injury. PubMed, Ovid, and ScienceDirect databases were searched. Studies were included for review if they specifically addressed genetic factors and tendon injuries in humans. Reviews, animal studies, or studies evaluating the influence of posttranscription factors and modifications (eg, proteins) were excluded. Results: Overall, 460 studies were available for initial review. After application of inclusion and exclusion criteria, 11 articles were ultimately included for qualitative synthesis. Upon screening of references of these 11 articles, an additional 15 studies were included in the final review, for a total of 26 studies. The genetic factors with the strongest evidence of association with tendon injury were those involving type V collagen A1, tenascin-C, matrix metalloproteinase–3, and estrogen-related receptor beta. Conclusion: The published literature is limited to relatively homogenous populations, with only level 3 and level 4 data. Additional research is needed to make further conclusions about the genetic factors involved in tendon injury. PMID:28856171

  15. Atelocollagen Enhances the Healing of Rotator Cuff Tendon in Rabbit Model.

    PubMed

    Suh, Dong-Sam; Lee, Jun-Keun; Yoo, Ji-Chul; Woo, Sang-Hun; Kim, Ga-Ram; Kim, Ju-Won; Choi, Nam-Yong; Kim, Yongdeok; Song, Hyun-Seok

    2017-07-01

    Failure of rotator cuff healing is a common complication despite the rapid development of surgical repair techniques for the torn rotator cuff. To verify the effect of atelocollagen on tendon-to-bone healing in the rabbit supraspinatus tendon compared with conventional cuff repair. Controlled laboratory study. A tear of the supraspinatus tendon was created and repaired in 46 New Zealand White rabbits. They were then randomly allocated into 2 groups (23 rabbits per group; 15 for histological and 8 for biomechanical test). In the experimental group, patch-type atelocollagen was implanted between bone and tendon during repair; in the control group, the torn tendon was repaired without atelocollagen. Each opposite shoulder served as a sham (tendon was exposed only). Histological evaluation was performed at 4, 8, and 12 weeks. Biomechanical tensile strength was tested 12 weeks after surgery. Histological evaluation scores of the experimental group (4.0 ± 1.0) were significantly superior to those of the control group (7.7 ± 2.7) at 12 weeks ( P = .005). The load to failure was significantly higher in the experimental group (51.4 ± 3.9 N) than in the control group (36.4 ± 5.9 N) ( P = .001). Histological and biomechanical studies demonstrated better results in the experimental group using atelocollagen in a rabbit model of the supraspinatus tendon tear. Atelocollagen patch could be used in the cuff repair site to enhance healing.

  16. Sensitivity of physical examination versus arthroscopy in diagnosing subscapularis tendon injury.

    PubMed

    Faruqui, Sami; Wijdicks, Coen; Foad, Abdullah

    2014-01-01

    The purpose of this study was to examine the accuracy of physical examination in the detection of subscapularis tendon tears and compare it with the gold standard of arthroscopy to determine whether clinical examination can reliably predict the presence of subscapularis tendon tears. This was a retrospective analysis of 52 patients (52 shoulders) who underwent arthroscopic subscapularis tendon repairs between September 2008 and April 2012. Positive findings on any combination of the belly press, lift-off, and bear hug tests constituted a positive physical examination result. There was a positive finding on physical examination in 42 of 52 patients. The sensitivity of the physical examination as a whole was 81%. The literature has shown that the belly press, bear hug, and lift-off tests are specific to the subscapularis tendon. To the authors’ knowledge, this is the first study to evaluate the sensitivity of these 3 separate clinical tests as a composite. Knowledge regarding the sensitivity of the subscapularis-specific physical examination as a composite can lead practitioners to implement all 3 components, even when 1 test has a negative finding, thus promoting a more thorough physical examination. Because unrepaired subscapularis tendon tears can result in poor outcomes in the repair of other rotator cuff tendons, a complete physical examination would be beneficial to patients with shoulder pathology. The authors conclude that physical examination, when performed consistently by an experienced practitioner, can reliably predict the presence of subscapularis tendon tears.

  17. [Zwipp Percutaneous Suture of the Achilles Tendon with the Dresden Instruments].

    PubMed

    Chmielnicki, M; Prokop, A

    2016-06-01

    Rupture of the Achilles tendon is the most common rupture of a tendon in man. Acute rupture of the Achilles tendon may be treated in a variety of manners, including conservative treatment, open suture and percutaneous suture. Surgical treatment of active patients is recommended, as the risk of re-rupture is greater after non-surgical treatment. The aim of surgery is adequate treatment of Achilles tendon rupture with a low rate of complications, high comfort for patients and fast social and occupational rehabilitation. The indication for surgical treatment of Achilles tendon rupture predominantly includes ruptures in active patients, with the goal of optimal functional rehabilitation. Furthermore, the percutaneous technique protects soft tissue, with a lower rate of wound healing disorders and infection than with open surgical treatment. In our clinic we perform the percutaneous suturing technique with the Dresden instruments. The surgical technique and functional aftercare are shown in a video clip. Between 2007 and 2013, we treated 212 patients with acute Achilles tendon rupture by surgery with the Dresden instruments. There were 7 re-ruptures (3.3 %) and one case of infection within one year of surgery. Percutaneous Achilles tendon suture technique with the Dresden instruments is a safe operation that protects soft tissue. Patient satisfaction is high and the rate of complications is low. This allows rapid social and occupational rehabilitation. Georg Thieme Verlag KG Stuttgart · New York.

  18. What We Should Know Before Using Tissue Engineering Techniques to Repair Injured Tendons: A Developmental Biology Perspective

    PubMed Central

    Liu, Chia-Feng; Aschbacher-Smith, Lindsey; Barthelery, Nicolas J.; Dyment, Nathaniel; Butler, David

    2011-01-01

    Tendons connect muscles to bones, and serve as the transmitters of force that allow all the movements of the body. Tenocytes are the basic cellular units of tendons, and produce the collagens that form the hierarchical fiber system of the tendon. Tendon injuries are common, and difficult to repair, particularly in the case of the insertion of tendon into bone. Successful attempts at cell-based repair therapies will require an understanding of the normal development of tendon tissues, including their differentiated regions such as the fibrous mid-section and fibrocartilaginous insertion site. Many genes are known to be involved in the formation of tendon. However, their functional roles in tendon development have not been fully characterized. Tissue engineers have attempted to generate functional tendon tissue in vitro. However, a lack of knowledge of normal tendon development has hampered these efforts. Here we review studies focusing on the developmental mechanisms of tendon development, and discuss the potential applications of a molecular understanding of tendon development to the treatment of tendon injuries. PMID:21314435

  19. Reconstruction of chronic achilles tendon rupture with the use of interposed tissue between the stumps.

    PubMed

    Yasuda, Toshito; Kinoshita, Mitsuo; Okuda, Ryuzo

    2007-04-01

    The gap between the tendon stumps in chronic Achilles tendon rupture has reportedly been filled with interposed scar tissue. In the authors' clinical experience, this interposed tissue is often thick and resists tension, so they considered it was possible to use the interposed tissue for reconstruction of Achilles tendon rupture. Scar tissue interposed between the tendon stumps has the capacity to form tendon-like repair tissue in patients with chronic Achilles tendon rupture. Case series; Level of evidence, 4. Six patients with chronic rupture of the Achilles tendon underwent tendon reconstruction with the use of interposed tissue between the stumps. The average time from the primary injury to surgery was 22 weeks (range, 9 to 30 weeks). Preoperative magnetic resonance imaging (MRI), histology of the interposed tissue, and clinical results were evaluated. The average postoperative follow-up period was 31 months (range, 24 to 43 months). Preoperative T2-weighted MRI in all cases revealed that chronically ruptured Achilles tendons were thickened and fusiform-shaped with diffuse intratendinous high-signal alterations throughout. Longitudinal high-signal bands were seen throughout the tendon, except at the musculotendinous junction and insertion on the calcaneus. Histologically, scar tissue interposed between the tendon stumps consisted of dense collagen fibers, and degenerative changes were not seen. After surgery, no patient had difficulty in walking or stair climbing, and all were able to perform a single-limb toe raise. The mean preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores were 88.2 and 98.3 points, respectively; the difference was statistically significant (P = .0277). Interposed tissue between the tendon stumps is suitable for repair of chronic Achilles tendon rupture if preoperative MRI shows a thickened fusiform-shaped Achilles tendon with diffuse intratendinous high-signal alterations throughout.

  20. Quantitative ultrasound method for assessing stress-strain properties and the cross-sectional area of Achilles tendon

    NASA Astrophysics Data System (ADS)

    Du, Yi-Chun; Chen, Yung-Fu; Li, Chien-Ming; Lin, Chia-Hung; Yang, Chia-En; Wu, Jian-Xing; Chen, Tainsong

    2013-12-01

    The Achilles tendon is one of the most commonly observed tendons injured with a variety of causes, such as trauma, overuse and degeneration, in the human body. Rupture and tendinosis are relatively common for this strong tendon. Stress-strain properties and shape change are important biomechanical properties of the tendon to assess surgical repair or healing progress. Currently, there are rather limited non-invasive methods available for precisely quantifying the in vivo biomechanical properties of the tendons. The aim of this study was to apply quantitative ultrasound (QUS) methods, including ultrasonic attenuation and speed of sound (SOS), to investigate porcine tendons in different stress-strain conditions. In order to find a reliable method to evaluate the change of tendon shape, ultrasound measurement was also utilized for measuring tendon thickness and compared with the change in tendon cross-sectional area under different stress. A total of 15 porcine tendons of hind trotters were examined. The test results show that the attenuation and broadband ultrasound attenuation decreased and the SOS increased by a smaller magnitude as the uniaxial loading of the stress-strain upon tendons increased. Furthermore, the tendon thickness measured with the ultrasound method was significantly correlated with tendon cross-sectional area (Pearson coefficient = 0.86). These results also indicate that attenuation of QUS and ultrasonic thickness measurement are reliable and potential parameters for assessing biomechanical properties of tendons. Further investigations are needed to warrant the application of the proposed method in a clinical setting.

  1. Continuous Shear Wave Elastography: a New Method to Measure in-vivo Viscoelastic Properties of Tendons

    PubMed Central

    Cortes, Daniel H.; Suydam, Stephen M.; Silbernagel, Karin Grävare; Buchanan, Thomas S.; Elliott, Dawn M.

    2015-01-01

    Viscoelastic mechanical properties are frequently altered after tendon injuries and during recovery. Therefore, non-invasive measurements of shear viscoelastic properties may help evaluate tendon recovery and compare the effectiveness of different therapies. The objectives of this study are to present an elastography method to measure localized viscoelastic properties of tendon and to present initial results in healthy and injured human Achilles and semitendinosus tendons. The technique used an external actuator to generate the shear waves in the tendon at different frequencies and plane wave imaging to measure shear wave displacements. For each of the excitation frequencies, maps of direction specific wave speeds were calculated using Local Frequency Estimation. Maps of viscoelastic properties were obtained using a pixel wise curve-fit of wave speed and frequency. The method was validated by comparing measurements of wave speed in agarose gels to those obtained using magnetic resonance elastography. Measurements in human healthy Achilles tendons revealed a pronounced increase in wave speed as function of frequency that highlights the importance of tendon viscoelasticity. Additionally, the viscoelastic properties of the Achilles tendon were larger than those reported for other tissues. Measurements in a tendinopathic Achilles tendon showed that it is feasible to quantify local viscoeasltic properties. Similarly, measurement in the semitendinosus tendon showed a substantial differences in viscoelastic properties between the healthy and contralateral tendons. Consequently, this technique has the potential of evaluating localized changes in tendon viscoelastic properties due to injury and during recovery in a clinical setting. PMID:25796414

  2. Ropivacaine alters the mechanical properties of hamstring tendons: In vitro controlled mechanical testing of tendons from living donors.

    PubMed

    Ollivier, M; Sbihi, J; Sbihi, A; Pithioux, M; Parratte, S; Argenson, J-N

    2017-11-01

    Intraarticular or periarticular injection of ropivacaine (RI) is an element of current knee surgery practices. The goal of this study was to determine the effects of RI on the mechanical properties of hamstring tendons. We hypothesized that RI would have a detrimental effect on the mechanical properties of periarticular soft tissues METHODS: A tensile test to failure was performed on 120 hamstring tendon segments harvested during ACL reconstruction surgery in 120 patients. Two sets of tensile tests were done. The first evaluated the effect of RI itself on the mechanical properties of tendons: 30 samples were soaked for 1hour in a 2% RI solution and compared to 30 samples soaked in a saline solution (control group). The second evaluated the effect of RI concentration on the mechanical properties of hamstring tendons: 30 samples were soaked for 1hour in a 2% RI solution and 30 samples were soaked in a 7.5% RI solution. In the first test, 29 samples from each group were analyzed as two samples (one in each group) failed at the grip interface. The specimens exposed to 2% RI had lower ultimate tensile strength (Δ=4.4MPa, P=0.001), strain energy (Δ=13MPa, P=0.001) and Young's modulus (Δ=1.6MPa, P=0.02) than the specimens in the control group. There was no significant difference in the strain at failure between groups (Δ=5%, P=0.3). In the second test, one specimen from the 7.5% RI group failed during the preloading and was excluded. There was no significant difference in terms of the load at failure and ultimate tensile stress (Δ=0.45MPa, P=0.6) and strain energy (Δ=0.49MPa, P=0.49) between the two groups. There were significant differences in terms of elongation at failure (Δ=28%, P=0.0003) and Young's modulus (Δ=2.6MPa, P=0.005), with the specimens exposed to 7.5% RI undergoing greater deformation and having a lower Young's modulus. While local RI injections are widely performed in clinical practice, the results of this in vitro study point to short

  3. Comparative morphology of the pollical distal phalanx.

    PubMed

    Shrewsbury, M M; Marzke, M W; Linscheid, R L; Reece, S P

    2003-05-01

    Functional analysis of human pollical distal phalangeal (PDP) morphology is undertaken to establish a basis for the assessment of fossil hominid PDP morphology. Features that contribute to the effectiveness of grips involving the distal thumb and finger pulp areas include: 1) distal thumb interphalangeal joint morphology, facilitating PDP conjunct pronation with flexion; 2) differentiation of a proximal, mobile pulp region from a distal, stable pulp region, providing for firm precision pinch grips and precision handling of objects; and 3) asymmetric attachment of the flexor pollicis longus (FPL) tendon fibers, favoring PDP conjunct pronation. A proportionately larger size of the ulnar vs. radial ungual spine suggests differential loading intensity of the ulnar side of the proximal ungual pulp and supporting nail bed. Stresses at the distal interphalangeal joint are indicated by the presence of a sesamoid bone within the volar (palmar) plate, which also increases the length of the flexor pollicis longus tendon moment arm. Dissections of specimens from six nonhuman primate genera indicate that these human features are shared variably with individuals in other species, although the full pattern of features appears to be distinctively human. Humans share variably with these other species all metric relationships examined here. The new data identify a need to systematically review long-standing assumptions regarding the range of precision and power manipulative capabilities that might reasonably be inferred from morphology of the distal phalangeal tuberosity and from the FPL tendon insertion site on the PDP. Copyright 2003 Wiley-Liss, Inc.

  4. Post-tensioning tendon force loss detection using low power pulsed eddy current measurement

    NASA Astrophysics Data System (ADS)

    Kim, Ji-Min; Lee, Jun; Sohn, Hoon

    2018-04-01

    In the field of bridge engineering, pre-fabrication of a bridge member and its construction in site have been issued and studied, which achieves improved quality and rapid construction. For integration of those pre-fabricated segments into a structural member (i.e., a concrete slab, girder and pier), post-tensioning (PT) technique is adopted utilizing a high-strength steel tendon, and an effective investigation of the remaining PT tendon force is essential to assure an overall structural integrity. This study proposes a pulsed eddy current based tendon force loss detection system. A compact eddy current sensor is designed to be installed on the surface of an anchor holding a steel PT tendon. The intensity of the induced eddy current varies with PT tendon force alteration due to the magnetostriction effect of a ferromagnetic material. The advantages of the proposed system are as follows: (1) low power consumption, (2) rapid inspection, and (3) simple installation. Its performance was validated experimentally in a full-scale lab test of a 3.3-m long, 15.2-mm diameter mono-tendon that was tensioned using a universal testing machine. Tendon force was controlled from 20 to 180 kN with 20 kN interval, and eddy current responses were measured and analyzed at each force condition. The proposed damage index and the amount of force loss of PT tendon were monotonically related, and an excessive loss as much as 30 % of an initially-introduced tendon force was successfully predicted.

  5. Evidence of accumulated stress in Achilles and anterior knee tendons in elite badminton players.

    PubMed

    Boesen, Anders Ploug; Boesen, Morten Ilum; Koenig, Merete Juhl; Bliddal, Henning; Torp-Pedersen, Soren; Langberg, Henning

    2011-01-01

    Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler (CD) activity in both the Achilles and patella tendon after loading during high-level badminton matches. The Achilles tendon was subdivided into a mid-tendon, pre-insertional, and insertional region and the anterior knee tendons into a quadriceps-, patella- and tuberositas region. Intra-tendinous flow was measured using both a semi-quantitative grading system (CD grading) and a quantitative scoring system (CF) on colour Doppler. Intra-tendinous flow in the Achilles and anterior knee tendons was examined in fourteen single players before tournament and after 1st and 2nd match, respectively on both the dominant and non-dominant side. All players had abnormal intra-tendinous flow (Colour Doppler ≥ grade 2) in at least one tendon in at least one scan during the tournament. At baseline, only two of the 14 players had normal flow in all the tendons examined. After 1st match, tendencies to higher intra-tendinous flow were observed in both the dominant patella tendon and non-dominant quadriceps tendon (P-values n.s.). After 2nd match, intra-tendinous flow was significant increased in the dominant patella tendon (P = 0.009). In all other locations, there was a trend towards a stepwise increase in intra-tendinous flow. The preliminary results indicate that high amount of intra-tendinous flow was found in elite badminton players at baseline and was increased after repetitive loading, especially in the patella tendon (dominant leg). The colour Doppler measurement can be used to determine changes in intra-tendinous flow after repetitive loading.

  6. Surgical anatomy of the lower trapezius tendon transfer.

    PubMed

    Omid, Reza; Cavallero, Matthew J; Granholm, Danielle; Villacis, Diego C; Yi, Anthony M

    2015-09-01

    The precise surgical anatomy of the lower trapezius tendon transfer has not been well described. A precise anatomic description of the different trapezius segments and the associated neurovascular structures is crucial for operative planning and execution. We aimed (1) to establish a reliable demarcation between the middle and lower trapezius, (2) to establish the precise relationship of the main neurovascular pedicle to the muscle belly, and (3) to evaluate the utility of the relationships established in (1) and (2) by using the results of this study to perform cadaveric lower trapezius tendon harvest. In phase 1, a single surgeon performed all measurements using 10 cadavers. In phase 2, 10 cadaveric shoulders were used to harvest the tendon by using the relationships established in phase 1. We found anatomically distinct insertion sites for the lower and middle trapezius. The lower trapezius inserted at the scapular spine dorsum and the middle trapezius inserted broadly along the superior surface of the scapular spine. The distance from tip of tendon insertion to the nearest nerve at the most superior portion of the lower trapezius was 58 mm (standard deviation ± 18). By use of these relationships, there were no cases of neurovascular injury during our cadaveric tendon harvests. The lower trapezius can be reliably and consistently identified without violating fibers of the middle trapezius. Muscle splitting can be performed safely without encountering the spinal accessory nerve (approximately 2 cm medial to the medial scapular border). Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  7. [A comparative study on repair of acute Achilles tendon rupture using three operating techniques].

    PubMed

    Wang, Ting; Mei, Guohua; Shi, Zhongmin; Chai, Yimin; Zhang, Changqing; Hou, Chunlin

    2012-07-01

    To compare the effectiveness of the 3 methods (traditional open Achilles tendon anastomosis, minimally invasive percutaneous Achilles tendon anastomosis, and Achilles tendon anastomosis limited incision) for acute Achilles tendon rupture so as to provide a reference for the choice of clinical treatment plans. Between December 2007 and March 2010, 69 cases of acute Achilles tendon rupture were treated by traditional open Achilles tendon anastomosis (traditional group, n=23), by minimally invasive percutaneous Achilles tendon anastomosis (minimally invasive group, n=23), and by Achilles tendon anastomosis limited incision (limited incision group, n=23). There was no significant difference in gender, age, mechanism of injury, and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score between 3 groups (P > 0.05). Minimally invasive group and limited incision group were significantly better than traditional group in hospitalization days and blood loss (P < 0.01). Incision infection occurred in 2 cases of traditional group, and healing of incision by first intention was achieved in all patients of the other 2 groups, showing significant difference in the complication rate (P < 0.05). Re-rupture of Achilles tendon occurred in 1 case (4.3%) of minimally invasive group and limited incision group respectively; no re-rupture was found in traditional group (0), showing significant difference when compared with the other 2 groups (P < 0.05). All cases were followed up 12-18 months with an average of 14.9 months. The function of the joint was restored. The AOFAS score was more than 90 points in 3 groups at 12 months after operation, showing no significant difference among 3 groups (P > 0.05). The above 3 procedures can be used to treat acute Achilles tendon rupture. However, minimally invasive percutaneous Achilles tendon anastomosis and Achilles tendon anastomosis limited incision have the advantages of less invasion, good healing, short hospitalization days

  8. Homologies of the transversospinalis muscles in the anterior presacral region of Sauria (crown Diapsida).

    PubMed

    Tsuihiji, Takanobu

    2005-02-01

    Homologies of muscles of the m. transversospinalis group in the dorsal and cervical regions in Sauria are established based on detailed dissections and published accounts of lepidosaurs, crocodylians, and birds. Attachments and directions of tendons comprising this muscle group are fairly conserved among the saurian clades, enabling rather robust inferences on muscle homologies. The innervation pattern indicates that mm. ascendentes are the most lateral muscles of the m. transversospinalis group in Aves, and are inferred to be homologous with the crocodylian m. tendinoarticularis based on their topological similarities. It is suggested here that the lepidosaurian articulo-parietalis part of m. longissimus cervico-capitis actually belongs to the m. transversospinalis group because its tendons of origin are shared with those of m. semispinalis. The avian m. complexus and the lateral part of the crocodylian m. transversospinalis capitis have origins and insertions similar to this lepidosaurian muscle, and are proposed to be homologous with the latter. In some birds, m. longus colli dorsalis, pars profunda continues directly into the anterior cervical region as m. splenius accessorius, suggesting a serially homologous relationship. Similarly, m. splenius anticus continues anteriorly from m. longus colli dorsalis, pars cranialis, and both of these muscles lie dorsal to m. splenius accessorius. Therefore, the currently used nomenclature that regards m. splenius accessorius as a part of m. longus colli dorsalis, pars cranialis and that regards m. splenius anticus as a part of the former muscle does not accurately reflect the serial homologies among these muscles and may not be justified. Copyright 2004 Wiley-Liss, Inc.

  9. Catalase-positive microperoxisomes in rat soleus and extensor digitorum longus muscle fiber types

    NASA Technical Reports Server (NTRS)

    Riley, Danny A.; Bain, James L. W.; Ellis, Stanley

    1988-01-01

    The size, distribution, and content of catalase-reactive microperoxisomes were investigated cytochemically in three types of muscle fibers from the soleus and the extensor digitorum longus (EDL) of male rats. Muscle fibers were classified on the basis of the mitochondrial content and distribution, the Z-band widths, and the size and shape of myofibrils as the slow-twitch oxidative (SO), the fast-twitch oxidative glycolytic (FOG), and the fast-twitch glycolytic (FG) fibers. It was found that both the EDL and soleus SO fibers possessed the largest microperoxisomes. A comparison of microperoxisome number per muscle fiber area or the microperoxisome area per fiber area revealed following ranking, starting from the largest number and the area-ratio values: soleus SO, EDL SO, EDL FOG, and EDL FG.

  10. The anteromedial approach to the psoas tendon in patients with cerebral palsy

    PubMed Central

    Poonnoose, Pradeep M.; Palocaren, Thomas

    2007-01-01

    Purpose Release of the psoas tendon for flexion deformity of the hip in children with cerebral palsy has traditionally been performed at the pelvic brim, lateral to the neurovascular bundle, or at its insertion into the lesser trochanter. As the psoas tendon is lateral to the pectineus, the traditional exposure of the tendon through an approach medial to the pectineus is limited by the extent to which the pectineus can be retracted proximally. Technical note We describe the use of the anteromedial approach used for the developmentally dislocated hip to expose the psoas tendon between the pectineus and the neurovascular bundle. This provides a much better visualisation of the tendon as it crosses the superior pubic ramus to its insertion. The use of this approach has not been described in cerebral palsy. PMID:19308518

  11. Response of tibialis anterior tendon to a chronic exposure of stretch-shortening cycles: age effects

    PubMed Central

    Ensey, James S; Hollander, Melinda S; Wu, John Z; Kashon, Michael L; Baker, Brent B; Cutlip, Robert G

    2009-01-01

    Background The purpose of the current study was to investigate the effects of aging on tendon response to repetitive exposures of stretch-shortening cycles (SSC's). Methods The left hind limb from young (3 mo, N = 4) and old (30 mo, N = 9) male Fisher 344 × Brown Norway rats were exposed to 80 maximal SSCs (60 deg/s, 50 deg range of motion) 3x/week for 4.5 weeks in vivo. After the last exposure, tendons from the tibialis anterior muscle were isolated, stored at -80°C, and then tested using a micro-mechanical testing machine. Deformation of each tendon was evaluated using both relative grip-to-grip displacements and reference marks via a video system. Results At failure, the young control tendons had higher strain magnitude than the young exposed (p < 0.01) and the old control tendons (p < .0001). Total load at inflection was affected by age only (p < 0.01). Old exposed and control tendons exhibited significantly higher loads at the inflection point than their young counterparts (p < 0.05 for both comparisons). At failure, the old exposed tendons carried higher loads than the young exposed tendons (p < 0.05). Stiffness was affected by age only at failure where the old tendons exhibited higher stiffness in both exposed and control tendons than their young counterparts (p < 0.05 and p < 0.01, respectively). Conclusion The chronic protocol enhanced the elastic stiffness of young tendon and the loads in both the young and old tendons. The old exposed tendons were found to exhibit higher load capacity than their younger counterparts, which differed from our initial hypothesis. PMID:19563638

  12. Evidence of structurally continuous collagen fibrils in tendons.

    PubMed

    Svensson, Rene B; Herchenhan, Andreas; Starborg, Tobias; Larsen, Michael; Kadler, Karl E; Qvortrup, Klaus; Magnusson, S Peter

    2017-03-01

    Tendons transmit muscle-generated force through an extracellular matrix of aligned collagen fibrils. The force applied by the muscle at one end of a microscopic fibril has to be transmitted through the macroscopic length of the tendon by mechanisms that are poorly understood. A key element in this structure-function relationship is the collagen fibril length. During embryogenesis short fibrils are produced but they grow rapidly with maturation. There is some controversy regarding fibril length in adult tendon, with mechanical data generally supporting discontinuity while structural investigations favor continuity. This study initially set out to trace the full length of individual fibrils in adult human tendons, using serial block face-scanning electron microscopy. But even with this advanced technique the required length could not be covered. Instead a statistical approach was used on a large volume of fibrils in shorter image stacks. Only a single end was observed after tracking 67.5mm of combined fibril lengths, in support of fibril continuity. To shed more light on this observation, the full length of a short tendon (mouse stapedius, 125μm) was investigated and continuity of individual fibrils was confirmed. In light of these results, possible mechanisms that could reconcile the opposing findings on fibril continuity are discussed. Connective tissues hold all parts of the body together and are mostly constructed from thin threads of the protein collagen (called fibrils). Connective tissues provide mechanical strength and one of the most demanding tissues in this regard are tendons, which transmit the forces generated by muscles. The length of the collagen fibrils is essential to the mechanical strength and to the type of damage the tissue may experience (slippage of short fibrils or breakage of longer ones). This in turn is important for understanding the repair processes after such damage occurs. Currently the issue of fibril length is contentious, but this

  13. Corrosion of post-tensioned tendons with deficient grout : final report.

    DOT National Transportation Integrated Search

    2016-10-20

    Recent corrosion failures of post-tensioned (PT) tendons in the Ringling Causeway Bridge (and corrosion development of PT tendons elsewhere in Florida) utilizing pre-packaged low-bleed specified grout products have spurred the need to evaluate what m...

  14. [Three-dimensional parallel collagen scaffold promotes tendon extracellular matrix formation].

    PubMed

    Zheng, Zefeng; Shen, Weiliang; Le, Huihui; Dai, Xuesong; Ouyang, Hongwei; Chen, Weishan

    2016-03-01

    To investigate the effects of three-dimensional parallel collagen scaffold on the cell shape, arrangement and extracellular matrix formation of tendon stem cells. Parallel collagen scaffold was fabricated by unidirectional freezing technique, while random collagen scaffold was fabricated by freeze-drying technique. The effects of two scaffolds on cell shape and extracellular matrix formation were investigated in vitro by seeding tendon stem/progenitor cells and in vivo by ectopic implantation. Parallel and random collagen scaffolds were produced successfully. Parallel collagen scaffold was more akin to tendon than random collagen scaffold. Tendon stem/progenitor cells were spindle-shaped and unified orientated in parallel collagen scaffold, while cells on random collagen scaffold had disorder orientation. Two weeks after ectopic implantation, cells had nearly the same orientation with the collagen substance. In parallel collagen scaffold, cells had parallel arrangement, and more spindly cells were observed. By contrast, cells in random collagen scaffold were disorder. Parallel collagen scaffold can induce cells to be in spindly and parallel arrangement, and promote parallel extracellular matrix formation; while random collagen scaffold can induce cells in random arrangement. The results indicate that parallel collagen scaffold is an ideal structure to promote tendon repairing.

  15. Achilles tendon vibration-induced changes in plantar flexor corticospinal excitability.

    PubMed

    Lapole, Thomas; Temesi, John; Gimenez, Philippe; Arnal, Pierrick J; Millet, Guillaume Y; Petitjean, Michel

    2015-02-01

    Daily Achilles tendon vibration has been shown to increase muscle force, likely via corticospinal neural adaptations. The aim of the present study was to determine the extent by which corticospinal excitability is influenced during direct Achilles tendon vibration. Motor-evoked potentials (MEPs) were elicited in the soleus (SOL), gastrocnemius medialis (GM) and tibialis anterior (TA) by transcranial magnetic stimulation of the motor cortical area of the leg with and without Achilles tendon vibration at various frequencies (50, 80 and 110 Hz). Contralateral homologues were also investigated. SOL and GM MEP amplitude significantly increased by 226 ± 188 and 66 ± 39%, respectively, during Achilles tendon vibration, without any difference between the tested frequencies. No MEP changes were reported for TA or contralateral homologues. Increased SOL and GM MEP amplitude suggests increased vibration-induced corticospinal excitability independent of vibration frequency.

  16. A Comparative Study of Clinical Outcomes and Second-Look Arthroscopic Findings between Remnant-Preserving Tibialis Tendon Allograft and Hamstring Tendon Autograft in Anterior Cruciate Ligament Reconstruction: Matched-Pair Design.

    PubMed

    Kim, You Keun; Ahn, Jong Hyun; Yoo, Jae Doo

    2017-12-01

    This study aimed to compare stability, functional outcome, and second-look arthroscopic findings after anterior cruciate ligament reconstruction between remnant-preserving tibialis tendon allograft and remnant-sacrificing hamstring tendon autograft. We matched two groups (remnant-preserving tibialis tendon allograft group and hamstring tendon autograft group) in terms of demographic characteristics, associated injury, and knee characteristics. Each group consisted of 25 patients. Operation time was longer in the remnant-preserving tibialis tendon allograft group, but there was no significant intergroup difference in stability, clinical outcome, and second-look arthroscopic findings. When an autograft is not feasible in anterior cruciate ligament reconstruction, the remnant-preserving technique can produce comparable results in terms of restoration of function, stability of the knee, and degree of synovium coverage at second-look arthroscopy compared to remnant-sacrificing hamstring autograft.

  17. Leukocyte-Reduced Platelet-Rich Plasma Normalizes Matrix Metabolism in Torn Human Rotator Cuff Tendons.

    PubMed

    Cross, Jessica A; Cole, Brian J; Spatny, Kaylan P; Sundman, Emily; Romeo, Anthony A; Nicholson, Greg P; Wagner, Bettina; Fortier, Lisa A

    2015-12-01

    The optimal platelet-rich plasma (PRP) for treatment of supraspinatus tendinopathy has not been determined. To evaluate the effect of low- versus high-leukocyte concentrated PRP products on catabolic and anabolic mediators of matrix metabolism in diseased rotator cuff tendons. Controlled laboratory study. Diseased supraspinatus tendons were treated with PRP made by use of 2 commercial systems: Arthrex Autologous Conditioned Plasma Double Syringe System (L(lo) PRP) and Biomet GPS III Mini Platelet Concentrate System (L(hi) PRP). Tendon explants were placed in 6-well plates and cultured in L(lo) PRP, L(hi) PRP, or control media (Dulbecco's Modified Eagle Medium + 10% fetal bovine serum) for 96 hours. Tendons were processed for hematoxylin-eosin histologic results and were scored with the modified Bonar scale. Group 1 tendons were defined as moderate tendinopathy (Bonar score <3); group 2 tendons were assessed as severely affected (Bonar score = 3). Transforming growth factor β-1 (TGFβ-1), interleukin-1β (IL-1β), interleukin-1 receptor antagonist (IL-1Ra), interleukin-6 (IL-6), interleukin-8 (IL-8), and matrix metalloproteinase-9 (MMP-9) concentrations in PRP media were measured by use of enzyme-linked immunosorbent assay after 96 hours of culture with diseased tendon. Tendon messenger RNA expression of collagen type I (COL1A1), collagen type III (COL3A1), cartilage oligomeric matrix protein (COMP), MMP-9, MMP-13, and IL-1β was measured with real-time quantitative polymerase chain reaction. Leukocytes and platelets were significantly more concentrated in L(hi) PRP compared with L(lo) PRP. Increased IL-1β was present in L(hi) PRP after culture with group 1 tendons. IL-6 was increased in L(hi) PRP after culture with group 2 tendons. Both TGFβ-1 and MMP-9 were increased in L(hi) PRP after culture with either tendon group. In L(lo) PRP cultures, IL-1Ra:IL-1β in PRP used as media and COL1A1:COL3A1 gene expression were increased for group 1 tendon cultures. Gene

  18. The biophysical characteristics of human composite flexor tendon allograft for upper extremity reconstruction.

    PubMed

    DeGeorge, Brent R; Rodeheaver, George T; Drake, David B

    2014-01-01

    Devastating volar hand injuries with significant damage to the skin and soft tissues, pulley structures and fibro-osseous sheath, flexor tendons, and volar plates pose a major problem to the reconstructive hand surgeon. Despite advances in tendon handling, operative technique, and postoperative hand rehabilitation, patients who have undergone flexor tendon reconstruction are often plagued by chronic pain, stiffness, and decreased range of motion with resultant decreased ability to work and poor quality of life. In this article, we expand the technique of human composite flexor tendon allografts (CFTAs), pioneered by Dr E.E. Peacock, Jr, which consist of both the intrasynovial and extrasynovial flexor digitorum superficialis and flexor digitorum profundus tendons and their respective fibro-osseous sheath consisting of the digital pulley structures, periosteum, and volar plates procured from cadaveric donors with the use of modern tissue processing techniques. Human cadaveric CFTAs were procured and divided into 2 groups-unprocessed CFTAs and processed CFTAs, which are cleansed and sterilized to a sterility assurance level of 10(-6). Physical length and width relationships as well as tensile strength and gliding resistance assessments were recorded pre-tissue and post-tissue processing. The histologic properties of the composite allografts were assessed before and after tissue processing. There was no significant difference with respect to physical properties of the composite allografts before or after tissue processing. The processed composite allografts demonstrated equivalent maximum load to failure and elastic modulus compared to unprocessed tendons. The gliding resistance of the composite tendon allografts was not significantly different between the 2 groups. The use of CFTAs addresses the issues of adhesion formation and lack of suitable donor material by providing a source of intrasynovial tendon in its unaltered fibro-osseous sheath without donor morbidity

  19. Direct Lentiviral-Cyclooxygenase 2 Application to the Tendon-Bone Interface Promotes Osteointegration and Enhances Return of the Pull-Out Tensile Strength of the Tendon Graft in a Rat Model of Biceps Tenodesis

    PubMed Central

    Wergedal, Jon E.; Stiffel, Virginia; Lau, Kin-Hing William

    2014-01-01

    This study sought to determine if direct application of the lentiviral (LV)-cyclooxygenase 2 (COX2) vector to the tendon-bone interface would promote osteointegration of the tendon graft in a rat model of biceps tenodesis. The LV-COX2 gene transfer strategy was chosen for investigation because a similar COX2 gene transfer strategy promoted bony bridging of the fracture gap during bone repair, which involves similar histologic transitions that occur in osteointegration. Briefly, a 1.14-mm diameter tunnel was drilled in the mid-groove of the humerus of adult Fischer 344 rats. The LV-COX2 or βgal control vector was applied directly into the bone tunnel and onto the end of the tendon graft, which was then pulled into the bone tunnel. A poly-L-lactide pin was press-fitted into the tunnel as interference fixation. Animals were sacrificed at 3, 5, or 8 weeks for histology analysis of osteointegration. The LV-COX2 gene transfer strategy enhanced neo-chondrogenesis at the tendon-bone interface but with only marginal effect on de novo bone formation. The tendon-bone interface of the LV-COX2-treated tenodesis showed the well-defined tendon-to-fibrocartilage-to-bone histologic transitions that are indicative of osteointegration of the tendon graft. The LV-COX2 in vivo gene transfer strategy also significantly enhanced angiogenesis at the tendon-bone interface. To determine if the increased osteointegration was translated into an improved pull-out mechanical strength property, the pull-out tensile strength of the LV-COX2-treated tendon grafts was determined with a pull-out mechanical testing assay. The LV-COX2 strategy yielded a significant improvement in the return of the pull-out strength of the tendon graft after 8 weeks. In conclusion, the COX2-based in vivo gene transfer strategy enhanced angiogenesis, osteointegration and improved return of the pull-out strength of the tendon graft. Thus, this strategy has great potential to be developed into an effective therapy to

  20. Continuous Shear Wave Elastography: A New Method to Measure Viscoelastic Properties of Tendons in Vivo.

    PubMed

    Cortes, Daniel H; Suydam, Stephen M; Silbernagel, Karin Grävare; Buchanan, Thomas S; Elliott, Dawn M

    2015-06-01

    Viscoelastic mechanical properties are frequently altered after tendon injuries and during recovery. Therefore, non-invasive measurements of shear viscoelastic properties may help evaluate tendon recovery and compare the effectiveness of different therapies. The objectives of this study were to describe an elastography method for measuring localized viscoelastic properties of tendons and to discuss the initial results in healthy and injured human Achilles and semitendinosus tendons. The technique used an external actuator to generate the shear waves in the tendon at different frequencies and plane wave imaging to measure shear wave displacements. For each of the excitation frequencies, maps of direction-specific wave speeds were calculated using local frequency estimation. Maps of viscoelastic properties were obtained using a pixel-wise curve fit of wave speed and frequency. The method was validated by comparing measurements of wave speed in agarose gels with those obtained using magnetic resonance elastography. Measurements in human healthy Achilles tendons revealed a pronounced increase in wave speed as a function of frequency, which highlights the importance of tendon viscoelasticity. Additionally, the viscoelastic properties of the Achilles tendon were larger than those reported for other tissues. Measurements in a tendinopathic Achilles tendon indicated that it is feasible to quantify local viscoelastic properties. Similarly, measurement in the semitendinosus tendon revealed substantial differences in viscoelastic properties between the healthy and contralateral tendons. Consequently, this technique has the potential to evaluate localized changes in tendon viscoelastic properties caused by injury and during recovery in a clinical setting. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  1. The effects of platelet lysate patches on the activity of tendon-derived cells.

    PubMed

    Costa-Almeida, Raquel; Franco, Albina R; Pesqueira, Tamagno; Oliveira, Mariana B; Babo, Pedro S; Leonor, Isabel B; Mano, João F; Reis, Rui L; Gomes, Manuela E

    2018-03-01

    Platelet-derived biomaterials are widely explored as cost-effective sources of therapeutic factors, holding a strong potential for endogenous regenerative medicine. Particularly for tendon repair, treatment approaches that shift the injury environment are explored to accelerate tendon regeneration. Herein, genipin-crosslinked platelet lysate (PL) patches are proposed for the delivery of human-derived therapeutic factors in patch augmentation strategies aiming at tendon repair. Developed PL patches exhibited a controlled release profile of PL proteins, including bFGF and PDGF-BB. Additionally, PL patches exhibited an antibacterial effect by preventing the adhesion, proliferation and biofilm formation by S. aureus, a common pathogen in orthopaedic surgical site infections. Furthermore, these patches supported the activity of human tendon-derived cells (hTDCs). Cells were able to proliferate over time and an up-regulation of tenogenic genes (SCX, COL1A1 and TNC) was observed, suggesting that PL patches may modify the behavior of hTDCs. Accordingly, hTDCs deposited tendon-related extracellular matrix proteins, namely collagen type I and tenascin C. In summary, PL patches can act as a reservoir of biomolecules derived from PL and support the activity of native tendon cells, being proposed as bioinstructive patches for tendon regeneration. Platelet-derived biomaterials hold great interest for the delivery of therapeutic factors for applications in endogenous regenerative medicine. In the particular case of tendon repair, patch augmentation strategies aiming at shifting the injury environment are explored to improve tendon regeneration. In this study, PL patches were developed with remarkable features, including the controlled release of growth factors and antibacterial efficacy. Remarkably, PL patches supported the activity of native tendon cells by up-regulating tenogenic genes and enabling the deposition of ECM proteins. This patch holds great potential towards

  2. The study of optical properties and proteoglycan content of tendons by PS-OCT

    NASA Astrophysics Data System (ADS)

    Yang, Ying; Rupani, Asha; Weightman, Alan; Wimpenny, Ian; Bagnaninchi, Pierre; Ahearne, Mark

    2011-03-01

    Tendons are load-bearing collagenous tissues consisting mainly of type I collagen and various proteoglycans (PGs) including decorin and versican. It is widely accepted that highly orientated collagen fibers in tendons a play critical role for transferring tensile stress and demonstrate birefringent optical properties. However, the influence that proteoglycans have on the optical properties of tendons is yet to be fully elucidated. Tendinopathy (defined as a syndrome of tendon pain, tenderness and swelling that affects the normal function of the tissue) is a common disease associated with sporting injuries or degeneration. PG's are the essential components of the tendon extracellular matrix; changes in their quantities and compositions have been associated with tendinopathy. In this study, polarization sensitive optical coherence tomography (PS-OCT) has been used to reveal the relationship between proteoglycan content/location and birefringent properties of tendons. Tendons dissected from freshly slaughtered chickens were imaged at regular intervals by PS-OCT and polarizing light microscope during the extraction of PGs or glycosaminoglycans using established protocols (guanidine hydrochloride (GuHCl) or proteinase K solution). The macroscopic and microscopic time lapsed images are complimentary; mutually demonstrating that there was a higher concentration of PG's in the outer sheath region than in the fascicles; and the integrity of the sheath affected extraction process and the OCT birefringence bands. Extraction of PGs using GuHCl disturbed the organization of local collagen bundles, which corresponded to a reduction in the frequency of birefringence bands and the band width by PS-OCT. The feature of OCT penetration depth helped us to define the heterogeneous distribution of PG's in tendon, which was complimented by polarizing light microscopy. The results provide new insight of tendon structure and also demonstrate a great potential for using PS-OCT as a

  3. Effect of Achilles tendon loading on plantar fascia tension in the standing foot.

    PubMed

    Cheung, Jason Tak-Man; Zhang, Ming; An, Kai-Nan

    2006-02-01

    The plantar fascia, which is one of the major arch-supporting structures of the human foot, sustains high tensions during weight-bearing. A positive correlation between Achilles tendon loading and plantar fascia tension has been reported. Excessive stretching and tightness of the Achilles tendon are thought to be the risk factors of plantar fasciitis but their biomechanical effects on the plantar fascia have not been fully addressed. A three-dimensional finite element model of the human foot and ankle, incorporating geometrical and material nonlinearity, was employed to investigate the loading response of the plantar fascia in the standing foot with different magnitudes of Achilles tendon loading. With the total ground reaction forces of one foot maintained at 350 N to represent half body weight, an increase in Achilles tendon load from (0-700 N) resulted in a general increase in total force and peak plantar pressure at the forefoot of up to about 250%. There was a lateral and anterior shift of the centre of pressure and a reduction in the arch height with an increasing Achilles tendon load as a result of the plantar flexion moment on the calcaneus. From the finite element predictions of simulated balanced standing, Achilles tendon forces of 75% of the total weight on the foot (350 N) were found to provide the closest match of the measured centre of pressure of the subject during balanced standing. Both the weight on the foot and Achilles tendon loading resulted in an increase in tension of the plantar fascia with the latter showing a two-times larger straining effect. Increasing tension on the Achilles tendon is coupled with an increasing strain on the plantar fascia. Overstretching of the Achilles tendon resulting from intense muscle contraction and passive stretching of tight Achilles tendon are plausible mechanical factors for overstraining of the plantar fascia.

  4. Association between statin therapy and tendon rupture: a case-control study.

    PubMed

    Beri, Abhimanyu; Dwamena, Francesca C; Dwamena, Ben A

    2009-05-01

    Although case reports of a possible association between statin therapy and tendon rupture have been published, no analytical studies exploring this relationship have been reported. We conducted a case-control study using the electronic medical records at Michigan State University from 2002 to 2007 to assess whether statin use is a risk factor for tendon rupture. We compared exposure to statins in 93 cases of tendon rupture with similar exposure in 279 sex- and age-matched controls. Exposure to statins was defined as documentation in the electronic medical record of statin use in the 12 months preceding tendon rupture. For controls, the exposure period was defined as 1 year preceding the last office visit. We used a multivariate logistic regression model, controlling for diabetes, renal disease, rheumatologic disease, and steroid use, to calculate the adjusted odds ratios (ORs). There was no significant difference between cases and controls in the rates of statin use, with either univariate [OR = 1.0, 95% confidence interval (CI) 0.54-1.84] or multivariate analyses (OR = 1.10, 95% CI 0.57-2.13). Based on predetermined subgroup analyses, statin exposure was found to be a significant risk factor for tendon rupture in women (adjusted OR = 3.76, 95% CI 1.11-12.75) but not in men (adjusted OR = 0.66, 95% CI 0.29-1.51). In conclusion, we found no overall association between statin use and tendon rupture, but subgroup analysis suggested that women with tendon rupture were more likely to be on statins.

  5. Differences in tendon properties in elite badminton players with or without patellar tendinopathy.

    PubMed

    Couppé, C; Kongsgaard, M; Aagaard, P; Vinther, A; Boesen, M; Kjaer, M; Magnusson, S P

    2013-03-01

    The aim of this study was to examine the structural and mechanical properties of the patellar tendon in elite male badminton players with and without patellar tendinopathy. Seven players with unilateral patellar tendinopathy (PT group) on the lead extremity (used for forward lunge) and nine players with no current or previous patellar tendinopathy (CT group) were included. Magnetic resonance imaging was used to assess distal patellar tendon dimensions. Patellar tendon mechanical properties were assessed using simultaneous tendon force and deformation measurements. Distal tendon cross-sectional area (CSA) normalized for body weight (mm(2) /kg(2/3) ) was lower in the PT group compared with the CT group on both the non-lead extremity (6.1 ± 0.3 vs 7.4 ± 0.2, P < 0.05) and the lead extremity (6.5 ± 0.6 vs 8.4 ± 0.3, P < 0.05). Distal tendon stress was higher in the PT group compared with the CT group for both the non-lead extremity (31 ± 1 vs 27 ± 1 MPa, P < 0.05) and the lead extremity (32 ± 3 vs 21 ± 3 MPa, P < 0.01). Conclusively, the PT group had smaller distal patellar tendon CSA on both the injured (lead extremity) and the uninjured side (non-lead extremity) compared with the CT group. Subsequently, the smaller CSA yielded a greater distal patellar tendon stress in the PT group. Therefore, a small tendon CSA may predispose to the development of tendinopathy. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  6. The plantaris tendon: a narrative review focusing on anatomical features and clinical importance.

    PubMed

    Spang, C; Alfredson, H; Docking, S I; Masci, L; Andersson, G

    2016-10-01

    In recent years, the plantaris tendon has been implicated in the development of chronic painful mid-portion Achilles tendinopathy. In some cases, a thickened plantaris tendon is closely associated with the Achilles tendon, and surgical excision of the plantaris tendon has been reported to be curative in patients who have not derived benefit following conservative treatment and surgical interventions. The aim of this review is to outline the basic aspects of, and the recent research findings, related to the plantaris tendon, covering anatomical and clinical studies including those dealing with histology, imaging and treatment. Cite this article: Bone Joint J 2016;98-B:1312-19. ©2016 The British Editorial Society of Bone & Joint Surgery.

  7. Tendon ruptures: mallet, flexor digitorum profundus.

    PubMed

    Yeh, Peter C; Shin, Steven S

    2012-08-01

    Mallet injuries are the most common closed tendon injury in the athlete. Flexor digitorum profundus ruptures are rare in baseball, but are common injuries in contact sports. The diagnosis for each condition is based on clinical examination, although radiographs should be evaluated for a possible bony component. Treatment for mallet injury depends on the athlete's goals of competition and understanding of the consequences of any treatment chosen. Gripping, throwing, and catching would be restricted or impossible with the injured finger immobilized. Treatment of FDP ruptures is almost always surgical and requires reattachment of the torn tendon to the distal phalanx. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. National Rugby League athletes and tendon tap reflex assessment: a matched cohort clinical study.

    PubMed

    Maurini, James; Ohmsen, Paul; Condon, Greg; Pope, Rodney; Hing, Wayne

    2016-11-04

    Limited research suggests elite athletes may differ from non-athletes in clinical tendon tap reflex responses. In this matched cohort study, 25 elite rugby league athletes were compared with 29 non-athletes to examine differences in tendon reflex responses. Relationships between reflex responses and lengths of players' careers were also examined. Biceps, triceps, patellar and Achilles tendon reflexes were clinically assessed. Right and left reflexes were well correlated for each tendon (r S  = 0.7-0.9). The elite rugby league athletes exhibited significantly weaker reflex responses than non-athletes in all four tendons (p < 0.005). Biceps reflexes demonstrated the largest difference and Achilles reflexes the smallest difference. Moderate negative correlations (r S  = -0.3-0.6) were observed between reflex responses and lengths of players' careers. Future research is required to further elucidate mechanisms resulting in the observed differences in tendon reflexes and to ensure clinical tendon tap examinations and findings can be interpreted appropriately in this athletic population.

  9. Sonographically Guided Plantaris Tendon Release: A Cadaveric Validation Study.

    PubMed

    Smith, Jay; Alfredson, Håkan; Masci, Lorenzo; Sellon, Jacob L; Woods, Charonn D

    2018-06-13

    The plantaris tendon (PT) has been implicated in the pathogenesis of symptoms in a subset of patients with Achilles region pain syndromes and has been traditionally managed via open surgical resection. Although the PT can be visualized on ultrasound, a minimally invasive technique for sonographically guided PT release has not been formally described. To validate a technique to perform sonographically guided PT release in an unembalmed cadaveric model. Prospective, cadaveric laboratory investigation. Procedural skills laboratory in a tertiary medical center. Twenty unembalmed cadaveric knee-ankle-foot specimens (10 right, 10 left; 6 male, 10 female) from 16 donors ages 55-96 years (mean 82.6 years) with BMI's of 14.1 to 33.2 kg/m 2 (mean 23.3 kg/m 2 ). Following simulated local anesthesia and sonographically guided hydrodissection of the plantaris tendon-Achilles tendon interval, a single experienced operator performed sonographically guided PT release on each specimen using an in-plane, lateral to medial approach, a commercially available, disposable 3.0 mm hook knife, and either a 17-5 MHz or 15-7 MHz linear array transducer. Each specimen was subsequently dissected to assess for PT release and iatrogenic injury. Status of the PT, Achilles tendon, and regional neurovascular structures as determined by dissection. All 20 PT releases were completed in a single attempt through a 3-5 mm incision. Dissection confirmed complete PT release in all specimens without damage to the adjacent Achilles tendon or regional neurovascular structures. Sonographically guided PT release is technically feasible and can be performed while avoiding injury to the Achilles tendon and regional neurovascular structures. Additional research is warranted to further define the role of sonographically guided PT release in patients with suspected PT-mediated Achilles region pain syndromes. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All

  10. Steroid injections - tendon, bursa, joint

    MedlinePlus

    ... a small amount of corticosteroid and a local anesthetic into the bursa. JOINT Any joint problem, such ... A small amount of corticosteroid and a local anesthetic will be injected into the joint. TENDON A ...

  11. Focal Experimental Injury Leads to Widespread Gene Expression and Histologic Changes in Equine Flexor Tendons

    PubMed Central

    Jacobsen, Else; Dart, Andrew J.; Mondori, Takamitsu; Horadogoda, Neil; Jeffcott, Leo B.; Little, Christopher B.; Smith, Margaret M.

    2015-01-01

    It is not known how extensively a localised flexor tendon injury affects the entire tendon. This study examined the extent of and relationship between histopathologic and gene expression changes in equine superficial digital flexor tendon after a surgical injury. One forelimb tendon was hemi-transected in six horses, and in three other horses, one tendon underwent a sham operation. After euthanasia at six weeks, transected and control (sham and non-operated contralateral) tendons were regionally sampled (medial and lateral halves each divided into six 3cm regions) for histologic (scoring and immunohistochemistry) and gene expression (real time PCR) analysis of extracellular matrix changes. The histopathology score was significantly higher in transected tendons compared to control tendons in all regions except for the most distal (P ≤ 0.03) with no differences between overstressed (medial) and stress-deprived (lateral) tendon halves. Proteoglycan scores were increased by transection in all but the most proximal region (P < 0.02), with increased immunostaining for aggrecan, biglycan and versican. After correcting for location within the tendon, gene expression for aggrecan, versican, biglycan, lumican, collagen types I, II and III, MMP14 and TIMP1 was increased in transected tendons compared with control tendons (P < 0.02) and decreased for ADAMTS4, MMP3 and TIMP3 (P < 0.001). Aggrecan, biglycan, fibromodulin, and collagen types I and III expression positively correlated with all histopathology scores (P < 0.001), whereas lumican, ADAMTS4 and MMP14 expression positively correlated only with collagen fiber malalignment (P < 0.001). In summary, histologic and associated gene expression changes were significant and widespread six weeks after injury to the equine SDFT, suggesting rapid and active development of tendinopathy throughout the entire length of the tendon. These extensive changes distant to the focal injury may contribute to poor functional outcomes and re

  12. Three dimensional microstructural network of elastin, collagen, and cells in Achilles tendons.

    PubMed

    Pang, Xin; Wu, Jian-Ping; Allison, Garry T; Xu, Jiake; Rubenson, Jonas; Zheng, Ming-Hao; Lloyd, David G; Gardiner, Bruce; Wang, Allan; Kirk, Thomas Brett

    2017-06-01

    Similar to most biological tissues, the biomechanical, and functional characteristics of the Achilles tendon are closely related to its composition and microstructure. It is commonly reported that type I collagen is the predominant component of tendons and is mainly responsible for the tissue's function. Although elastin has been found in varying proportions in other connective tissues, previous studies report that tendons contain very small quantities of elastin. However, the morphology and the microstructural relationship among the elastic fibres, collagen, and cells in tendon tissue have not been well examined. We hypothesize the elastic fibres, as another fibrillar component in the extracellular matrix, have a unique role in mechanical function and microstructural arrangement in Achilles tendons. It has been shown that elastic fibres present a close connection with the tenocytes. The close relationship of the three components has been revealed as a distinct, integrated and complex microstructural network. Notably, a "spiral" structure within fibril bundles in Achilles tendons was observed in some samples in specialized regions. This study substantiates the hierarchical system of the spatial microstructure of tendon, including the mapping of collagen, elastin and tenocytes, with 3-dimensional confocal images. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1203-1214, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  13. TEMPERATURE-DEPENDENT VISCOELASTIC PROPERTIES OF THE HUMAN SUPRASPINATUS TENDON

    PubMed Central

    Huang, Chun-Yuh; Wang, Vincent M.; Flatow, Evan L.; Mow, Van C.

    2009-01-01

    Temperature effects on the viscoelastic properties of the human supraspinatus tendon were investigated using static stress-relaxation experiments and Quasi-Linear Viscoelastic (QLV) theory. Twelve supraspinatus tendons were randomly assigned to one of two test groups for tensile testing using the following sequence of temperatures: (1) 37°C, 27°C, and 17°C (Group I, n=6), or (2) 42°C, 32°C, and 22°C (Group II, n=6). QLV parameter C was found to increase at elevated temperatures, suggesting greater viscous mechanical behavior at higher temperatures. Elastic parameters A and B showed no significant difference among the six temperatures studied, implying that the viscoelastic stress response of the supraspinatus tendon is not sensitive to temperature over shorter testing durations. Using regression analysis, an exponential relationship between parameter C and test temperature was implemented into QLV theory to model temperature-dependent viscoelastic behavior. This modified approach facilitates the theoretical determination of the viscoelastic behavior of tendons at arbitrary temperatures. PMID:19159888

  14. The Achilles Tendon Insertion is Crescent-shaped: An In Vitro Anatomic Investigation

    PubMed Central

    Arentz, Sabine; Nauck, Tanja; Dorn-Lange, Nadja V.; Konerding, Moritz A.

    2008-01-01

    Anatomic and operative textbooks and current literature do not clearly describe the Achilles tendon interface to the calcaneal tuberosity. We dissected 51 specimens to identify the detailed anatomy of the Achilles tendon insertion. Achilles tendon fascicles expanded from the anterior aspect of the distal Achilles tendon over the retrocalcaneal bursa to the anterior part of the Haglund’s tuberosity in nearly half of the specimens. The insertion of the transverse section of the Achilles tendon regularly had a crescent-shape corresponding to the posterior calcaneal prominence. In transverse sections, all specimens had a curved appearance with a radius of curvature ranging from 13.8 mm to 43.6 mm (mean, 20.4 mm) and Achilles tendon extensions to the lateral and medial calcaneal surfaces reached 1.0 mm (mean) and 3.5 mm (mean) anterior in relation to the most posterior point of the calcaneal tuberosity. Knowledge of the arcuate configuration and of the medial and lateral extensions of the plantaris and the Achilles tendon insertion with respect to the transverse plane is important to avoid iatrogenic complications during resection of Haglund’s tuberosity. PMID:18506561

  15. Comparison of Autograft and Allograft with Surface Modification for Flexor Tendon Reconstruction: A Canine in Vivo Model.

    PubMed

    Wei, Zhuang; Reisdorf, Ramona L; Thoreson, Andrew R; Jay, Gregory D; Moran, Steven L; An, Kai-Nan; Amadio, Peter C; Zhao, Chunfeng

    2018-04-04

    Flexor tendon injury is common, and tendon reconstruction is indicated clinically if the primary repair fails or cannot be performed immediately after tendon injury. The purpose of the current study was to compare clinically standard extrasynovial autologous graft (EAG) tendon and intrasynovial allogeneic graft (IAG) that had both undergone biolubricant surface modification in a canine in vivo model. Twenty-four flexor digitorum profundus (FDP) tendons from the second and fifth digits of 12 dogs were used for this study. In the first phase, a model of failed FDP tendon repair was created. After 6 weeks, the ruptured FDP tendons with a scarred digit were reconstructed with the use of either EAG or IAG tendons treated with carbodiimide-derivatized hyaluronic acid and lubricin. At 12 weeks after tendon reconstruction, the digits were harvested for functional, biomechanical, and histologic evaluations. The tendon failure model was a clinically relevant and reproducible model for tendon reconstruction. The IAG group demonstrated improved digit function with decreased adhesion formation, lower digit work of flexion, and improved graft gliding ability compared with the EAG group. However, the IAG group had decreased healing at the distal tendon-bone junction. Our histologic findings verified the biomechanical evaluations and, further, showed that cellular repopulation of allograft at 12 weeks after reconstruction is still challenging. FDP tendon reconstruction using IAG with surface modification has some beneficial effects for reducing adhesions but demonstrated inferior healing at the distal tendon-bone junction compared with EAG. These mixed results indicate that vitalization and turnover acceleration are crucial to reducing failure of reconstruction with allograft. Flexor tendon reconstruction is a common surgical procedure. However, postoperative adhesion formation may lead to unsatisfactory clinical outcomes. In this study, we developed a potential flexor tendon

  16. A robust method for RNA extraction and purification from a single adult mouse tendon.

    PubMed

    Grinstein, Mor; Dingwall, Heather L; Shah, Rishita R; Capellini, Terence D; Galloway, Jenna L

    2018-01-01

    Mechanistic understanding of tendon molecular and cellular biology is crucial toward furthering our abilities to design new therapies for tendon and ligament injuries and disease. Recent transcriptomic and epigenomic studies in the field have harnessed the power of mouse genetics to reveal new insights into tendon biology. However, many mouse studies pool tendon tissues or use amplification methods to perform RNA analysis, which can significantly increase the experimental costs and limit the ability to detect changes in expression of low copy transcripts. Single Achilles tendons were harvested from uninjured, contralateral injured, and wild type mice between three and five months of age, and RNA was extracted. RNA Integrity Number (RIN) and concentration were determined, and RT-qPCR gene expression analysis was performed. After testing several RNA extraction approaches on single adult mouse Achilles tendons, we developed a protocol that was successful at obtaining high RIN and sufficient concentrations suitable for RNA analysis. We found that the RNA quality was sensitive to the time between tendon harvest and homogenization, and the RNA quality and concentration was dependent on the duration of homogenization. Using this method, we demonstrate that analysis of Scx gene expression in single mouse tendons reduces the biological variation caused by pooling tendons from multiple mice. We also show successful use of this approach to analyze Sox9 and Col1a2 gene expression changes in injured compared with uninjured control tendons. Our work presents a robust, cost-effective, and straightforward method to extract high quality RNA from a single adult mouse Achilles tendon at sufficient amounts for RT-qPCR as well as RNA-seq. We show this can reduce variation and decrease the overall costs associated with experiments. This approach can also be applied to other skeletal tissues, as well as precious human samples.

  17. Diclofenac Patch for Treatment of Mild to Moderate Tendonitis or Bursitis

    ClinicalTrials.gov

    2008-08-05

    Rotator Cuff Tendonitis; Bicipital Tendonitis; Subdeltoid Bursitis of the Shoulder; Subacromial Bursitis of the Shoulder; Medial Epicondylitis of the Elbow; Lateral Epicondylitis of the Elbow; DeQuervain's Tenosynovitis of the Wrist

  18. An advanced glycation endproduct (AGE)-rich diet promotes accumulation of AGEs in Achilles tendon.

    PubMed

    Skovgaard, Dorthe; Svensson, Rene B; Scheijen, Jean; Eliasson, Pernilla; Mogensen, Pernille; Hag, Anne Mette F; Kjær, Michael; Schalkwijk, Casper G; Schjerling, Peter; Magnusson, Stig P; Couppé, Christian

    2017-03-01

    Advanced Glycation Endproducts (AGEs) accumulate in long-lived tissue proteins like collagen in bone and tendon causing modification of the biomechanical properties. This has been hypothesized to raise the risk of orthopedic injury such as bone fractures and tendon ruptures. We evaluated the relationship between AGE content in the diet and accumulation of AGEs in weight-bearing animal Achilles tendon. Two groups of mice (C57BL/6Ntac) were fed with either high-fat diet low in AGEs high-fat diet (HFD) ( n  = 14) or normal diet high in AGEs (ND) ( n  = 11). AGE content in ND was six to 50-fold higher than HFD The mice were sacrificed at week 40 and Achilles and tail tendons were carefully excised to compare weight and nonweight-bearing tendons. The amount of the AGEs carboxymethyllysine (CML), methylglyoxal-derived hydroimidazolone (MG-H1) and carboxyethyllysine (CEL) in Achilles and tail tendon was measured using ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) and pentosidine with high-pressure liquid chromatography (HPLC) with fluorescent detection. AGEs in Achilles tendon were higher than in tail tendon for CML ( P  < 0.0001), CEL ( P  < 0.0001), MG-H1 and pentosidine (for both ND and HFD) ( P  < 0.0001). The AGE-rich diet (ND) resulted in an increase in CML ( P  < 0.0001), MG-H1 ( P  < 0.001) and pentosidine ( P  < 0.0001) but not CEL, in Achilles and tail tendon. This is the first study to provide evidence for AGE accumulation in injury-prone, weight-bearing Achilles tendon associated with intake of an AGE-rich diet. This indicates that food-derived AGEs may alter tendon properties and the development of tendon injuries. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  19. Comparative anatomy of the radial sesamoid bone in the polar bear (Ursus maritimus), the brown bear (Ursus arctos) and the giant panda (Ailuropoda melanoleuca).

    PubMed

    Endo, H; Makita, T; Sasaki, M; Arishima, K; Yamamoto, M; Hayashi, Y

    1999-08-01

    Since we have clarified the manipulation mechanism using the radial sesamoid (RS) in the giant panda (Ailuropoda melanoleuca), our aim in this study is to examine the position, shape and function of the RS morphologically, and to observe the attachment to the RS of the M. abductor pollicis longus and the M. opponens pollicis in the other Ursidae species. So, we focused on the carpus and manus of the polar bear (Ursus maritimus) and the brown bear (Ursus arctos) in this study. The RS was tightly articulated to the radial carpal, and could not adduct-abduct independently of the radial carpal. The M. abductor pollicis longus tendon and the M. opponens pollicis belly were attached to the RS, independently. In the polar bear, the deep concave and the flat surface were confirmed in attachment area for these two muscles. The morphological relationship between the RS and the M. abductor pollicis longus and the M. opponens pollicis in the two species of bears were essentially consistent with that in the giant panda. It also demonstrated that the manipulation mechanism of the giant panda has been completely based on the functional relationship between the small RS, and the M. abductor pollicis longus and the M. opponens pollicis in Ursidae species.

  20. Experimental study of the effects of helium-neon laser radiation on repair of injured tendon

    NASA Astrophysics Data System (ADS)

    Xu, Yong-Qing; Li, Zhu-Yi; Weng, Long-Jiang; An, Mei; Li, Kai-Yun; Chen, Shao-Rong; Wang, Jian-Xin; Lu, Yu

    1993-03-01

    Despite extensive research into the biology of tendon healing, predictably restoring normal function to a digit after a flexor tendon laceration remains one of the most difficult problems facing the hand surgeon. The challenge of simultaneously achieving tendon healing while minimizing the peritendinous scar formation, which limits tendon gliding, has captured the attention of investigators for many years. It has been said that low-power density helium-neon laser radiation had effects on anti-inflammation, detumescence, progressive wound healing, and reducing intestinal adhesions. This experimental study aims at whether helium-neon laser can reduce injured tendon adhesions and improve functional recovery of the injured tendon. Fifty white Leghorn hens were used. Ten were randomly assigned as a normal control group, the other forty were used in the operation. After anesthetizing them with Amytal, a half of the profundus tendons of the second and third foretoes on both sides of the feet were cut. Postoperatively, the hens moved freely in the cages. One side of the toes operated on were randomly chosen as a treatment group, the other side served as an untreated control group. The injured tendon toes in the treatment group were irradiated for twenty minutes daily with a fiber light needle of helium-neon laser therapeutic apparatus (wavelength, 6328 angstroms) at a constant power density of 12.74 mW/cm2, the first exposure taking place 24 hours after the operation. The longest course of treatment was 3 weeks. The control group was not irradiated. At 3 days, 1, 2, 3, and 5 weeks after surgery, 8 hens were sacrificed and their tendons were examined. The experimental results: (1) active, passive flexion and tendon gliding functional recovery were significantly better in the treatment group (p < 0.01); (2) width and thickness of the tendon at the cut site were significantly smaller in the treatment group (p < 0.01); (3) degrees of tendon adhesions were significantly lighter