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Sample records for achilles tendon tissue

  1. Achilles Tendonitis

    MedlinePlus

    ... You Prevent Achilles Tendonitis? Take these steps to reduce your risk of Achilles tendonitis: Stay in good shape year-round and try to keep your muscles as strong as they can be. Strong, flexible muscles work more efficiently and put less stress on your tendon. Increase the intensity and length ...

  2. Achilles Tendonitis

    MedlinePlus

    ... up. Tight calf muscles or muscles that lack flexibility decrease a person's range of motion and put an extra strain on the tendon. Running or exercising on a hard or uneven surface or doing lunges or plyometrics without adequate training. A traumatic injury to the Achilles tendon. How ...

  3. Achilles tendon repair

    MedlinePlus

    Achilles tendon rupture-surgery; Percutaneous Achilles tendon rupture repair ... To fix your torn Achilles tendon, the surgeon will: Make a cut down the back of your heel Make several small cuts rather than one large cut ...

  4. Achilles tendon injuries in athletes.

    PubMed

    Kvist, M

    1994-09-01

    varus is found in athletes with Achilles tendon overuse injuries, reflecting the predisposing role of ankle joint overpronation. Athletes with the major stress in lower extremities have often a limited range of motion in the passive dorsiflexion of the ankle joint and total subtalar joint mobility, which seems to be predisposing factor for these injuries. Various predisposing transient factors are found in about one-third of athletes with Achilles tendon overuse injuries; of these, traumatic factors (mostly minor injuries) predominate. The typical histological features of chronically inflamed paratendineal tissue of the Achilles tendon are profound proliferation of loose, immature connective tissue and marked obliterative and degenerative alterations in the blood vessels. These changes cause continuing leakage of plasma proteins, which may have an important role in the pathophysiology of these injuries. The chronically inflamed paratendineal tissues of the Achilles tendon do not seem to have enough capacity to form mature connective tissue.

  5. Alterations in the Achilles tendon after inflammation in surrounding tissue

    PubMed Central

    Vieira, Cristiano Pedrozo; Guerra, Flávia da Ré; de Oliveira, Letícia Prado; de Almeida, Marcos dos Santos; Pimentel, Edson Rosa

    2012-01-01

    Objective To analyze the characteristics of the Achilles tendon of rats after induction of localized inflammation in the rat paw. Methods In our study three groups were used: inflamed group with carrageenan in rat paw (G1); saline group (G2) and control group (G3). After 4 hours the animals were euthanized and the Achilles tendon removed. Results No significant differences were observed in the analysis of non-collagenous proteins, glycosaminoglycans and hydroxyproline in the groups but a tendency of reduction was verified in G1. As regards the organization of collagen molecules, no differences were observed between groups. With respect to MMPs activity, a stronger presence of the active isoform of MMP-2 in G1 was observed, suggesting that the remodeling was occurring. Conclusion Thus, we conclude that the inflammatory process in rat paw may affect the remodeling of tendons located near the inflamed site. Level of Evidence I, Prognostic Studies - Investigating the Effect of a Patient Characteristic on the Outcome of Disease PMID:24453615

  6. Lack of tissue renewal in human adult Achilles tendon is revealed by nuclear bomb (14)C.

    PubMed

    Heinemeier, Katja Maria; Schjerling, Peter; Heinemeier, Jan; Magnusson, Stig Peter; Kjaer, Michael

    2013-05-01

    Tendons are often injured and heal poorly. Whether this is caused by a slow tissue turnover is unknown, since existing data provide diverging estimates of tendon protein half-life that range from 2 mo to 200 yr. With the purpose of determining life-long turnover of human tendon tissue, we used the (14)C bomb-pulse method. This method takes advantage of the dramatic increase in atmospheric levels of (14)C, produced by nuclear bomb tests in 1955-1963, which is reflected in all living organisms. Levels of (14)C were measured in 28 forensic samples of Achilles tendon core and 4 skeletal muscle samples (donor birth years 1945-1983) with accelerator mass spectrometry (AMS) and compared to known atmospheric levels to estimate tissue turnover. We found that Achilles tendon tissue retained levels of (14)C corresponding to atmospheric levels several decades before tissue sampling, demonstrating a very limited tissue turnover. The tendon concentrations of (14)C approximately reflected the atmospheric levels present during the first 17 yr of life, indicating that the tendon core is formed during height growth and is essentially not renewed thereafter. In contrast, (14)C levels in muscle indicated continuous turnover. Our observation provides a fundamental premise for understanding tendon function and pathology, and likely explains the poor regenerative capacity of tendon tissue.

  7. Complete Achilles tendon ruptures.

    PubMed

    Landvater, S J; Renström, P A

    1992-10-01

    Achilles tendon ruptures can be treated nonsurgically in the nonathletic or low-end recreational athletic patient, particularly those more than 50 years of age, provided the treating physician does not delay in the diagnosis and treatment (preferably less than 48 hrs and possibly less than 1 week). The patient should be advised of the higher incidence of re-rupture of the tendon when treated nonsurgically. Surgical treatment is recommended for patients who are young and athletic. This is particularly true because the major criticism of surgical treatment has been the complication rate, which has decreased to a low level and to a mild degree, usually not significantly affecting the repair over time. Surgical treatment in these individuals seems to be superior not only in regard to re-rupture but also in assuring the correct apposition of the tendon ends and in placing the necessary tension on the tendon to secure appropriate orientation of the collagen fibers. This in turn allows them to regain full strength, power, endurance, and an early return to sports. Surgery is also recommended for late diagnosed ruptures where there is significant lengthening of the tendon. Surgical technique should involve a medial incision to avoid the sural nerve, absorbable suture, and augmentation with fascia or tendon where there is a gap or late rupture. Postoperatively, the immobilization should be 7 to 10 days in a splint. A walking boot with early motion in plantar flexion or a short leg cast with the tendon under slight tension should thereafter be used for 4 to 5 weeks. An early and well-supervised rehabilitation program should be initiated to restore the patient to the preinjury activity level.

  8. 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.

  9. Reconstruction of defects involving the Achilles tendon and local soft tissues: a quick solution for a lingering problem.

    PubMed

    Soons, J; Rakhorst, H A; Ruettermann, M; Luijsterburg, A J M; Bos, P K; Zöphel, O T

    2015-02-01

    A total of seven patients (six men and one woman) with a defect in the Achilles tendon and overlying soft tissue underwent reconstruction using either a composite radial forearm flap (n = 3) or an anterolateral thigh flap (n = 4). The Achilles tendons were reconstructed using chimeric palmaris longus (n = 2) or tensor fascia lata (n = 2) flaps or transfer of the flexor hallucis longus tendon (n = 3). Surgical parameters such as the rate of complications and the time between the initial repair and flap surgery were analysed. Function was measured objectively by recording the circumference of the calf, the isometric strength of the plantar flexors and the range of movement of the ankle. The Achilles tendon Total Rupture Score (ATRS) questionnaire was used as a patient-reported outcome measure. Most patients had undergone several previous operations to the Achilles tendon prior to flap surgery. The mean time to flap surgery was 14.3 months (2.1 to 40.7). At a mean follow-up of 32.3 months (12.1 to 59.6) the circumference of the calf on the operated lower limb was reduced by a mean of 1.9 cm (sd 0.74) compared with the contralateral limb (p = 0.042). The mean strength of the plantar flexors on the operated lower limb was reduced to 88.9% of that of the contralateral limb (p = 0.043). There was no significant difference in the range of movement between the two sides (p = 0.317). The mean ATRS score was 72 points (sd 20.0). One patient who had an initial successful reconstruction developed a skin defect of the composite flap 12 months after free flap surgery and this resulted in recurrent infections, culminating in transtibial amputation 44 months after reconstruction. These otherwise indicate that reconstruction of the Achilles tendon combined with flap cover results in a successful and functional reconstruction.

  10. Achilles Tendon Rupture

    PubMed Central

    Wertz, Jess; Galli, Melissa; Borchers, James R.

    2013-01-01

    Context: Achilles tendon (AT) rupture in athletes is increasing in incidence and accounts for one of the most devastating sports injuries because of the threat to alter or end a career. Despite the magnitude of this injury, reliable risk assessment has not been clearly defined, and prevention strategies have been limited. The purpose of this review is to identify potential intrinsic and extrinsic risk factors for AT rupture in aerial and ground athletes stated in the current literature. Evidence Acquisition: A MEDLINE search was conducted on AT rupture, or “injury” and “risk factors” and “athletes” from 1980 to 2011. Emphasis was placed on epidemiology, etiology, and review articles focusing on the risk for lower extremity injury in runners and gymnasts. Thirty articles were reviewed, and 22 were included in this assessment. Results: Aerial and ground athletes share many intrinsic risk factors for AT rupture, including overuse and degeneration of the tendon as well as anatomical variations that mechanically put an athlete at risk. Older athletes, athletes atypical in size for their sport, high tensile loads, leg dominance, and fatigue also may increase risk. Aerial athletes tend to have more extrinsic factors that play a role in this injury due to the varying landing surfaces from heights and technical maneuvers performed at various skill levels. Conclusion: Risk assessment for AT rupture in aerial and ground athletes is multivariable and difficult in terms of developing prevention strategies. Quantitative measures of individual risk factors may help identify major contributors to injury. PMID:24427410

  11. Lubricin in human achilles tendon: The evidence of intratendinous sliding motion and shear force in achilles tendon.

    PubMed

    Sun, Yu-Long; Wei, Zhuang; Zhao, Chunfeng; Jay, Gregory D; Schmid, Thomas M; Amadio, Peter C; An, Kai-Nan

    2015-06-01

    Achilles tendon is one of the most commonly injured tendons. Mechanical force is regarded as a major causative factor. However, the biomechanics of Achilles tendon and mechanical mechanism of the injuries are unclear. Lubricin expresses at regions exposed to sliding motion and shear force in a number of tissues. This study investigated the distribution and concentration of lubricin in human Achilles tendons for better understanding the biomechanics of Achilles tendon. Achilles tendons were harvested from nine cadavers. Lubricin was extracted from various locations proximal to the calcaneal insertion and quantified with ELISA. The distribution of lubricin was investigated with immunohistochemistry. Lubricin was mainly identified at the interfaces of tendon fascicles, especially in the mid-portion of the tendon. The concentration of lubricin in Achilles tendons varied by individual and the distance from its calcaneal insertion. The distal portion of the tendon had a higher concentration of lubricin than the proximal regions of the tendon. This study suggests the presence of intratendinous sliding motion of fascicles and shear force at interfaces of fascicles in human Achilles tendon. Shear force could be an important mechanical factor for the development of Achilles tendinopathy and rupture.

  12. 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.

  13. The role of tendon microcirculation in Achilles and patellar tendinopathy.

    PubMed

    Knobloch, Karsten

    2008-04-30

    Tendinopathy is of distinct interest as it describes a painful tendon disease with local tenderness, swelling and pain associated with sonographic features such as hypoechogenic texture and diameter enlargement. Recent research elucidated microcirculatory changes in tendinopathy using laser Doppler flowmetry and spectrophotometry such as at the Achilles tendon, the patellar tendon as well as at the elbow and the wrist level. Tendon capillary blood flow is increased at the point of pain. Tendon oxygen saturation as well as tendon postcapillary venous filling pressures, determined non-invasively using combined Laser Doppler flowmetry and spectrophotometry, can quantify, in real-time, how tendon microcirculation changes over with pathology or in response to a given therapy. Tendon oxygen saturation can be increased by repetitive, intermittent short-term ice applications in Achilles tendons; this corresponds to 'ischemic preconditioning', a method used to train tissue to sustain ischemic damage. On the other hand, decreasing tendon oxygenation may reflect local acidosis and deteriorating tendon metabolism. Painful eccentric training, a common therapy for Achilles, patellar, supraspinatus and wrist tendinopathy decreases abnormal capillary tendon flow without compromising local tendon oxygenation. Combining an Achilles pneumatic wrap with eccentric training changes tendon microcirculation in a different way than does eccentric training alone; both approaches reduce pain in Achilles tendinopathy. The microcirculatory effects of measures such as extracorporeal shock wave therapy as well as topical nitroglycerine application are to be studied in tendinopathy as well as the critical question of dosage and maintenance. Interestingly it seems that injection therapy using color Doppler for targeting the area of neovascularisation yields to good clinical results with polidocanol sclerosing therapy, but also with a combination of epinephrine and lidocaine.

  14. [The Achilles tendon in sports].

    PubMed

    Segesser, B; Goesele, A; Renggli, P

    1995-06-01

    Achillodynia is a generic term for various types of ailments in the region of the Achilles tendon. For adequate therapy a specific diagnosis is absolutely necessary. Besides an accurate anamnesis and the right choice of terrain and shoes, as well as a clinical examination where one has to specifically keep an eye on muscular imbalance between the gastrocnemius and the soleus muscle and disorders of the ligamentous control of the calcaneus caused by fibular ligament instabilities, a procedure such as radiology, ultrasound, and MR imaging is inevitable. From the differential diagnosis point of view a distinction between peritendinitis, mechanically triggered bursitis (calcaneal and subachilles), bony alterations of the calcaneus (calcaneus spur, Haglund exostosis persistent nucleus of the apophysis, fatigue fracture, etc) and a partial or total rupture (a one-time occurrence or multiple occurrences) has to be made. Occasionally, entrapment of the ramus calcaneus of the sural nerve causes calcaneal pain. If clinically not confirmed, lumbar pain ought to be taken into consideration (discopathy, Bechterew disease, etc). Metabolic disorders (especially uric acid) and underlying rheumatic diseases must be excluded. The therapy of achillodynia includes local and peroral antiphlogistic medication as a concomitant measure. More important is the causal influence of etiological factors, i.e., the correction of muscular imbalance, ensuring control of the calcaneus through bandages and adjustment of sport shoes, changes in training buildup and exercise intensity, just to mention a few. If necessary, surgically splitting the peritendineum, sanitation of a partial rupture, bursectomy and removal of mechanically obstructive exostosis must be done.

  15. Substantial creep in healing human Achilles tendons. A pilot study

    PubMed Central

    Aspenberg, Per; Schepull, Thorsten

    2015-01-01

    Summary Background healing after rupture of the Achilles tendon can be described in terms of mechanical properties of the new-formed tissue, constituting the tendon callus. In previous human studies, the elastic modulus and the density remained almost constant during 3 months after mobilization started, and then improved up to one year. So far, time-dependent deformation of the healing human tendon has not been reported. Methods in a series of 16 patients, operated with Achilles tendon suture, we implanted tantalum beads into the tendon and measured the distance between them repeatedly during 3 min of constant loading, using an ordinary image intensifier. The patients unloaded their leg for 30 min before the test. To avoid bias, all images were investigated in a randomized and blinded order. Results total strain during 3 min of constant loading at 7 weeks post injury amounted to 5%, and at 19 weeks to 3%. About half of the strain, after the loading was applied, occurred during the second and third min. Considerable strain also occurred just before loading, when the patient was told that a load would be applied, but before this was actually done. Conclusion the measurements were crude, and this study should be seen as a pilot. Still, visco-elastic properties seem to dominate the mechanical behavior the healing Achilles tendon from start of mobilization to 19 weeks, at least when tested after 30 min rest. This deserves further studies with more precise methods. PMID:26605187

  16. Predicting tenocyte expression profiles and average molecular concentrations in Achilles tendon ECM from tissue strain and fiber damage.

    PubMed

    Mehdizadeh, Arash; Gardiner, Bruce S; Lavagnino, Michael; Smith, David W

    2017-03-13

    In this study, we propose a method for quantitative prediction of changes in concentrations of a number of key signaling, structural and effector molecules within the extracellular matrix of tendon. To achieve this, we introduce the notion of elementary cell responses (ECRs). An ECR defines a normal reference secretion profile of a molecule by a tenocyte in response to the tenocyte's local strain. ECRs are then coupled with a model for mechanical damage of tendon collagen fibers at different straining conditions of tendon and then scaled up to the tendon tissue level for comparison with experimental observations. Specifically, our model predicts relative changes in ECM concentrations of transforming growth factor beta, interleukin 1 beta, collagen type I, glycosaminoglycan, matrix metalloproteinase 1 and a disintegrin and metalloproteinase with thrombospondin motifs 5, with respect to tendon straining conditions that are consistent with the observations in the literature. In good agreement with a number of in vivo and in vitro observations, the model provides a logical and parsimonious explanation for how excessive mechanical loading of tendon can lead to under-stimulation of tenocytes and a degenerative tissue profile, which may well have bearing on a better understanding of tendon homeostasis and the origin of some tendinopathies.

  17. Rat Achilles tendon healing: mechanical loading and gene expression.

    PubMed

    Eliasson, Pernilla; Andersson, Therese; Aspenberg, Per

    2009-08-01

    Injured tendons require mechanical tension for optimal healing, but it is unclear which genes are upregulated and responsible for this effect. We unloaded one Achilles tendon in rats by Botox injections in the calf muscles. The tendon was then transected and left to heal. We studied mechanical properties of the tendon calluses, as well as mRNA expression, and compared them with loaded controls. Tendon calluses were studied 3, 8, 14, and 21 days after transection. Intact tendons were studied similarly for comparison. Altogether 110 rats were used. The genes were chosen for proteins marking inflammation, growth, extracellular matrix, and tendon specificity. In intact tendons, procollagen III and tenascin-C were more expressed in loaded than unloaded tendons, but none of the other genes was affected. In healing tendons, loading status had small effects on the selected genes. However, TNF-alpha, transforming growth factor-beta1, and procollagens I and III were less expressed in loaded callus tissue at day 3. At day 8 procollagens I and III, lysyl oxidase, and scleraxis had a lower expression in loaded calluses. However, by days 14 and 21, procollagen I, cartilage oligomeric matrix protein, tenascin-C, tenomodulin, and scleraxis were all more expressed in loaded calluses. In healing tendons, the transverse area was larger in loaded samples, but material properties were unaffected, or even impaired. Thus mechanical loading is important for growth of the callus but not its mechanical quality. The main effect of loading during healing might thereby be sought among growth stimulators. In the late phase of healing, tendon-specific genes (scleraxis and tenomodulin) were upregulated with loading, and the healing tissue might to some extent represent a regenerate rather than a scar.

  18. Temporal Healing in Rat Achilles Tendon: Ultrasound Correlations

    PubMed Central

    Chamberlain, Connie S.; Duenwald-Kuehl, Sarah E.; Okotie, Gregory; Brounts, Sabrina H.; Baer, Geoffrey S.; Vanderby, Ray

    2012-01-01

    The purpose of this study was to explore whether a new ultrasound-based technique correlates with mechanical and biological metrics that describe the tendon healing. Achilles tendons in 32 rats were unilaterally transected and allowed to heal without repair. At 7, 9, 14, or 29 days post-injury, tendons were collected and examined for healing via ultrasound image analysis, mechanical testing, and immunohistochemistry. Consistent with previous studies, we observe that the healing tendons are mechanically inferior (ultimate stress, ultimate load, and normalized stiffness) and biologically altered (cellular and ECM factors) compared to contralateral controls with an incomplete recovery over healing time. Unique to this study, we report: 1) Echo intensity (defined by gray-scale brightness in the ultrasound image) in the healing tissue is related to stress and normalized stiffness. 2) Elongation to failure is relatively constant so that tissue normalized stiffness is linearly correlated with ultimate stress. Together, 1 and 2 suggest a method to quantify mechanical compromise in healing tendons. 3) The amount and type of collagen in healing tendons associates with their strength and normalized stiffness as well as their ultrasound echo intensity. 4) A significant increase of periostin in the healing tissues suggests an important but unexplored role for this ECM protein in tendon healing. PMID:23149902

  19. Achilles tendon and plantar fascia in recently diagnosed type II diabetes: role of body mass index.

    PubMed

    Abate, Michele; Schiavone, Cosima; Di Carlo, Luigi; Salini, Vincenzo

    2012-07-01

    Previous research has shown that plantar fascia and Achilles tendon thickness is increased in diabetes. The aims of present study were to assess whether tendon changes can occur in the early stages of the disease and to evaluate the extent of the influence of body mass index (BMI). The study population included 51 recent-onset type II diabetic subjects, who were free from diabetic complications, divided according to BMI into three groups (normal weight, overweight, and obese). Eighteen non-diabetic, normal-weight subjects served as controls. Plantar fascia and Achilles tendon thickness was measured by means of sonography. The groups were well balanced for age and sex. In all the diabetic subjects, plantar fascia and Achilles tendon thickness was increased compared to the controls (p < 0.001, p = 0.01, p = 0.003, respectively). A significant relationship was found between plantar fascia thickness and BMI values (r = 0.749, p < 0.0001), while the correlation between BMI and Achilles tendon was weaker (r = 0.399, p = 0.004). This study shows that plantar fascia and Achilles tendon thickness is increased in the early stages of type II diabetes and that BMI is related more to plantar fascia than Achilles tendon thickness. Further longitudinal studies are needed to evaluate whether these early changes can overload the metatarsal heads and increase the stress transmitted to plantar soft tissues, thus representing an additional risk factor for foot ulcer development.

  20. Development of the human Achilles tendon enthesis organ.

    PubMed

    Shaw, H M; Vázquez, Osorio T; McGonagle, D; Bydder, G; Santer, R M; Benjamin, M

    2008-12-01

    The attachment of the Achilles tendon is part of an 'enthesis organ' that reduces stress concentration at the hard-soft tissue interface. The organ also includes opposing sesamoid and periosteal fibrocartilages, a bursa and Kager's fat pad. In addition, the deep crural and plantar fasciae contribute to Achilles stress dissipation and could also be regarded as components. Here we describe the sequence in which these various tissues differentiate. Serial sections of feet from spontaneously aborted foetuses (crown rump lengths 22-322 mm) were examined. All slides formed part of an existing collection of histologically sectioned embryological material, obtained under Spanish law and housed in the Universidad Complutense, Madrid. From the earliest stages, it was evident that the Achilles tendon and plantar fascia had a mutual attachment to the calcaneal perichondrium. The first components of the enthesis organ to appear (in the 45-mm foetus) were the retrocalcaneal bursa and the crural fascia. The former developed by cavitation within the mesenchyme that later gave rise to Kager's fat pad. The tip of the putative fat pad protruded into the developing bursa in the 110-mm foetus and fully differentiated adipocytes were apparent in the 17-mm foetus. All three fibrocartilages were first recognisable in the 332-mm foetus--at which time adipogenesis had commenced in the heel fat pad. The sequence in which the various elements became apparent suggests that bursal formation and the appearance of the crural fascia may be necessary to facilitate the foot movements that subsequently lead to fibrocartilage differentiation. The later commencement of adipogenesis in the heel than in Kager's pad probably reflects the non-weight environment in utero. The direct continuity between plantar fascia and Achilles tendon that is characteristic of the adult reflects the initial attachment of both structures to the calcaneal perichondrium rather than to the skeletal anlagen itself.

  1. 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.

  2. Effects of BMP-12-Releasing Sutures on Achilles Tendon Healing

    PubMed Central

    Chamberlain, Connie S.; Lee, Jae-Sung; Leiferman, Ellen M.; Maassen, Nicholas X.; Baer, Geoffrey S.

    2015-01-01

    Tendon healing is a complex coordinated event orchestrated by numerous biologically active proteins. Unfortunately, tendons have limited regenerative potential and as a result, repair may be protracted months to years. Current treatment strategies do not offer localized delivery of biologically active proteins, which may result in reduced therapeutic efficacy. Surgical sutures coated with nanostructured minerals may provide a potentially universal tool to efficiently incorporate and deliver biologically active proteins directly to the wound. Additionally, previous reports indicated that treatment with bone morphogenetic protein-12 (BMP-12) improved tendon healing. Based on this information, we hypothesized that mineral-coated surgical sutures may be an effective platform for localized BMP-12 delivery to an injured tendon. The objective of this study was, therefore, to elucidate the healing effects of mineral-coated sutures releasing BMP-12 using a rat Achilles healing model. The effects of BMP-12-releasing sutures were also compared with standard BMP-12 delivery methods, including delivery of BMP-12 through collagen sponge or direct injection. Rat Achilles tendons were unilaterally transected and repaired using BMP-12-releasing suture (0, 0.15, 1.5, or 3.0 μg), collagen sponge (0 or 1.5 μg BMP-12), or direct injection (0 or 1.5 μg). By 14 days postinjury, repair with BMP-12-releasing sutures reduced the appearance of adhesions to the tendon and decreased total cell numbers. BMP-12 released from sutures and collagen sponge also tended to improve collagen organization when compared with BMP-12 delivered through injection. Based on these results, the release of a protein from sutures was able to elicit a biological response. Furthermore, BMP-12-releasing sutures modulated tendon healing, and the delivery method dictated the response of the healing tissue to BMP-12. PMID:25354567

  3. ggstThe role of tendon microcirculation in Achilles and patellar tendinopathy

    PubMed Central

    Knobloch, Karsten

    2008-01-01

    Tendinopathy is of distinct interest as it describes a painful tendon disease with local tenderness, swelling and pain associated with sonographic features such as hypoechogenic texture and diameter enlargement. Recent research elucidated microcirculatory changes in tendinopathy using laser Doppler flowmetry and spectrophotometry such as at the Achilles tendon, the patellar tendon as well as at the elbow and the wrist level. Tendon capillary blood flow is increased at the point of pain. Tendon oxygen saturation as well as tendon postcapillary venous filling pressures, determined non-invasively using combined Laser Doppler flowmetry and spectrophotometry, can quantify, in real-time, how tendon microcirculation changes over with pathology or in response to a given therapy. Tendon oxygen saturation can be increased by repetitive, intermittent short-term ice applications in Achilles tendons; this corresponds to 'ischemic preconditioning', a method used to train tissue to sustain ischemic damage. On the other hand, decreasing tendon oxygenation may reflect local acidosis and deteriorating tendon metabolism. Painful eccentric training, a common therapy for Achilles, patellar, supraspinatus and wrist tendinopathy decreases abnormal capillary tendon flow without compromising local tendon oxygenation. Combining an Achilles pneumatic wrap with eccentric training changes tendon microcirculation in a different way than does eccentric training alone; both approaches reduce pain in Achilles tendinopathy. The microcirculatory effects of measures such as extracorporeal shock wave therapy as well as topical nitroglycerine application are to be studied in tendinopathy as well as the critical question of dosage and maintenance. Interestingly it seems that injection therapy using color Doppler for targeting the area of neovascularisation yields to good clinical results with polidocanol sclerosing therapy, but also with a combination of epinephrine and lidocaine. PMID:18447938

  4. Chronic Achilles Tendon Rupture Treated with Allograft: A Case Report.

    PubMed

    Restuccia, Giuseppe; Lippi, Alessandro; Casella, Francesco; Citarelli, Carmine; Sacchetti, Federico; Benifei, Maurizio

    2017-02-07

    In clinical practice, chronic Achilles tendon ruptures are uncommon. Usually, these lesions are discovered four to six weeks after injuries. More frequently, Achilles tendon ruptures are acute and treated with tendon sutures.1 Many surgical techniques are available to treat chronic lesions such as sutures or V-Y elongation with or without augments.2-3 Our case is about a chronic Achilles tendon rupture discovered two years after injury. Our patient came to our attention with a 6 cm tendon gap. We performed tendon repair with cadaver allograft. After four years of follow-up, our patient has a complete functional recovery and he can normally perform daily and working tasks without pain.

  5. 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.

  6. Ultrasonic evaluations of Achilles tendon mechanical properties poststroke

    PubMed Central

    Zhao, Heng; Ren, Yupeng; Wu, Yi-Ning; Liu, Shu Q.; Zhang, Li-Qun

    2009-01-01

    Spasticity, contracture, and muscle weakness are commonly observed poststroke in muscles crossing the ankle. However, it is not clear how biomechanical properties of the Achilles tendon change poststroke, which may affect functions of the impaired muscles directly. Biomechanical properties of the Achilles tendon, including the length and cross-sectional area, in the impaired and unimpaired sides of 10 hemiparetic stroke survivors were evaluated using ultrasonography. Elongation of the Achilles tendon during controlled isometric ramp-and-hold and ramping up then down contractions was determined using a block-matching method. Biomechanical changes in stiffness, Young's modulus, and hysteresis of the Achilles tendon poststroke were investigated by comparing the impaired and unimpaired sides of the 10 patients. The impaired side showed increased tendon length (6%; P = 0.04), decreased stiffness (43%; P < 0.001), decreased Young's modulus (38%; P = 0.005), and increased mechanical hysteresis (1.9 times higher; P < 0.001) compared with the unimpaired side, suggesting Achilles tendon adaptations to muscle spasticity, contracture, and/or disuse poststroke. In vivo quantitative characterizations of the tendon biomechanical properties may help us better understand changes of the calf muscle-tendon unit as a whole and facilitate development of more effective treatments. PMID:19118156

  7. Surgical Strategy for the Chronic Achilles Tendon Rupture

    PubMed Central

    Yang, Liu; Yin, Li

    2016-01-01

    Background. Chronic Achilles tendon rupture is usually misdiagnosed and treated improperly. This study aims to better understand the treatment of chronic Achilles tendon rupture. Methods. Patients who were not able to perform a single-limb heel rise were chosen. Pre- and postoperative magnetic resonance imaging (MRI) were conducted. By evaluating the presence or absence of Achilles tendon stumps and the gap length of rupture, V-Y advancement, gastrocnemius fascial turndown flap, or flexor halluces longus tendon transfer were selected for tendon repair. The function of ankle and foot was assessed by American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores and Achilles Tendon Total Rupture Score (ATRS). Results. Twenty-nine patients were followed up. One patient had superficial incision infection, which was healed after debridement and oral antibiotics. Three months postoperatively, MRI showed some signs of inflammation, which disappeared at one or two years postoperatively. All patients were able to perform a single-limb heel rise. Mean AOFAS scores and ATRS scores were increased at the latest follow-up. Conclusion. Surgical options can be determined by evaluating the presence of the Achilles tendon stumps and the gap length, which can avoid using the nearby tendon and yield satisfactory functional results. PMID:27847806

  8. Ultrasonic evaluations of Achilles tendon mechanical properties poststroke.

    PubMed

    Zhao, Heng; Ren, Yupeng; Wu, Yi-Ning; Liu, Shu Q; Zhang, Li-Qun

    2009-03-01

    Spasticity, contracture, and muscle weakness are commonly observed poststroke in muscles crossing the ankle. However, it is not clear how biomechanical properties of the Achilles tendon change poststroke, which may affect functions of the impaired muscles directly. Biomechanical properties of the Achilles tendon, including the length and cross-sectional area, in the impaired and unimpaired sides of 10 hemiparetic stroke survivors were evaluated using ultrasonography. Elongation of the Achilles tendon during controlled isometric ramp-and-hold and ramping up then down contractions was determined using a block-matching method. Biomechanical changes in stiffness, Young's modulus, and hysteresis of the Achilles tendon poststroke were investigated by comparing the impaired and unimpaired sides of the 10 patients. The impaired side showed increased tendon length (6%; P = 0.04), decreased stiffness (43%; P < 0.001), decreased Young's modulus (38%; P = 0.005), and increased mechanical hysteresis (1.9 times higher; P < 0.001) compared with the unimpaired side, suggesting Achilles tendon adaptations to muscle spasticity, contracture, and/or disuse poststroke. In vivo quantitative characterizations of the tendon biomechanical properties may help us better understand changes of the calf muscle-tendon unit as a whole and facilitate development of more effective treatments.

  9. A minimally invasive "overwrapping" technique for repairing neglected ruptures of the Achilles tendon.

    PubMed

    Lui, Tun Hing

    2014-01-01

    About 10% to 25% of acute ruptures of the Achilles tendon go undiagnosed for some time beyond what would be optimal for repair and a return to optimal function. Managing these chronic or neglected ruptures is a surgical challenge, because the tendon ends retract and atrophy and could develop a short, fibrous distal stump. In the present report, a patient with a ruptured right Achilles tendon, neglected for approximately 10 years, is described. The chronically injured tendon was successfully treated by overwrapping the interposed scar at the rupture site. This minimally invasive technique restored tension to the tendon, a prerequisite for which was the presence of functional triceps surae, confirmed by identification of gross contraction of the muscle during tiptoeing. The procedure is contraindicated when the scar tissue is not intact and does not have sufficient laxity to allow adequate dorsiflexion of the ankle after overwrapping the tendon or when the triceps surae are nonfunctional.

  10. Quadriceps tendon allografts as an alternative to Achilles tendon allografts: a biomechanical comparison.

    PubMed

    Mabe, Isaac; Hunter, Shawn

    2014-12-01

    Quadriceps tendon with a patellar bone block may be a viable alternative to Achilles tendon for anterior cruciate ligament reconstruction (ACL-R) if it is, at a minimum, a biomechanically equivalent graft. The objective of this study was to directly compare the biomechanical properties of quadriceps tendon and Achilles tendon allografts. Quadriceps and Achilles tendon pairs from nine research-consented donors were tested. All specimens were processed to reduce bioburden and terminally sterilized by gamma irradiation. Specimens were subjected to a three phase uniaxial tension test performed in a custom environmental chamber to maintain the specimens at a physiologic temperature (37 ± 2 °C) and misted with a 0.9 % NaCl solution. There were no statistical differences in seven of eight structural and mechanical between the two tendon types. Quadriceps tendons exhibited a significantly higher displacement at maximum load and significantly lower stiffness than Achilles tendons. The results of this study indicated a biomechanical equivalence of aseptically processed, terminally sterilized quadriceps tendon grafts with bone block to Achilles tendon grafts with bone block. The significantly higher displacement at maximum load, and lower stiffness observed for quadriceps tendons may be related to the failure mode. Achilles tendons had a higher bone avulsion rate than quadriceps tendons (86 % compared to 12 %, respectively). This was likely due to observed differences in bone block density between the two tendon types. This research supports the use of quadriceps tendon allografts in lieu of Achilles tendon allografts for ACL-R.

  11. The plantaris tendon in association with mid-portion Achilles tendinosis: tendinosis-like morphological features and presence of a non-neuronal cholinergic system.

    PubMed

    Spang, Christoph; Alfredson, Håkan; Ferguson, Mark; Roos, Beverley; Bagge, Johan; Forsgren, Sture

    2013-05-01

    The plantaris tendon is often neglected in morphological/clinical studies on the lower extremity. There is, however, clinical evidence that the plantaris tendon is involved in cases with Achilles midportion tendinopathy/tendinosis. It is nevertheless unclear if the plantaris tendon exhibits tendinosis-like features in this situation. We therefore investigated the plantaris tendon of patients with midportion Achilles tendinosis when the plantaris tendon was found to be located very close to or invaginated into the Achilles tendon, a situation which very often has been found to be the case. There was a very large number of tenocytes in the tendon tissue and the tenocytes showed abnormal and irregular appearances, exhibiting widened/rounded and wavy appearances, and were frequently lined up in rows. These features are characteristic features in Achilles tendinosis tendons. The tendon cells showed a distinct immunoreaction for the acetylcholine (ACh) -producing enzyme choline acetyltransferase (ChAT). Frequent fibroblasts were found in the loose connective tissue and these cells also showed a marked ChAT immunoreaction. The study shows that the plantaris tendon is morphologically affected in a similar way to the Achilles tendon in cases with midportion Achilles tendinosis and medial pain. The plantaris tendon may accordingly be a co-factor in these cases. The results also favour that there is a local ACh production both within the tendon tissue of the plantaris tendon and in the loose connective tissue. In conclusion, it is evident that plantaris tendons lying invaginated into or very close to the Achilles tendon in cases with midportion Achilles tendinosis show similar tendinosis features, as previously shown for the Achilles tendon itself in these cases.

  12. Characterization and comparison of post-natal rat Achilles tendon-derived stem cells at different development stages.

    PubMed

    Chen, Jialin; Zhang, Wei; Liu, Zeyu; Zhu, Ting; Shen, Weiliang; Ran, Jisheng; Tang, Qiaomei; Gong, Xiaonan; Backman, Ludvig J; Chen, Xiao; Chen, Xiaowen; Wen, Feiqiu; Ouyang, Hongwei

    2016-03-14

    Tendon stem/progenitor cells (TSPCs) are a potential cell source for tendon tissue engineering. The striking morphological and structural changes of tendon tissue during development indicate the complexity of TSPCs at different stages. This study aims to characterize and compare post-natal rat Achilles tendon tissue and TSPCs at different stages of development. The tendon tissue showed distinct differences during development: the tissue structure became denser and more regular, the nuclei became spindle-shaped and the cell number decreased with time. TSPCs derived from 7 day Achilles tendon tissue showed the highest self-renewal ability, cell proliferation, and differentiation potential towards mesenchymal lineage, compared to TSPCs derived from 1 day and 56 day tissue. Microarray data showed up-regulation of several groups of genes in TSPCs derived from 7 day Achilles tendon tissue, which may account for the unique cell characteristics during this specific stage of development. Our results indicate that TSPCs derived from 7 day Achilles tendon tissue is a superior cell source as compared to TSPCs derived from 1 day and 56 day tissue, demonstrating the importance of choosing a suitable stem cell source for effective tendon tissue engineering and regeneration.

  13. A Fibre-Reinforced Poroviscoelastic Model Accurately Describes the Biomechanical Behaviour of the Rat Achilles Tendon

    PubMed Central

    Heuijerjans, Ashley; Matikainen, Marko K.; Julkunen, Petro; Eliasson, Pernilla; Aspenberg, Per; Isaksson, Hanna

    2015-01-01

    Background Computational models of Achilles tendons can help understanding how healthy tendons are affected by repetitive loading and how the different tissue constituents contribute to the tendon’s biomechanical response. However, available models of Achilles tendon are limited in their description of the hierarchical multi-structural composition of the tissue. This study hypothesised that a poroviscoelastic fibre-reinforced model, previously successful in capturing cartilage biomechanical behaviour, can depict the biomechanical behaviour of the rat Achilles tendon found experimentally. Materials and Methods We developed a new material model of the Achilles tendon, which considers the tendon’s main constituents namely: water, proteoglycan matrix and collagen fibres. A hyperelastic formulation of the proteoglycan matrix enabled computations of large deformations of the tendon, and collagen fibres were modelled as viscoelastic. Specimen-specific finite element models were created of 9 rat Achilles tendons from an animal experiment and simulations were carried out following a repetitive tensile loading protocol. The material model parameters were calibrated against data from the rats by minimising the root mean squared error (RMS) between experimental force data and model output. Results and Conclusions All specimen models were successfully fitted to experimental data with high accuracy (RMS 0.42-1.02). Additional simulations predicted more compliant and soft tendon behaviour at reduced strain-rates compared to higher strain-rates that produce a stiff and brittle tendon response. Stress-relaxation simulations exhibited strain-dependent stress-relaxation behaviour where larger strains produced slower relaxation rates compared to smaller strain levels. Our simulations showed that the collagen fibres in the Achilles tendon are the main load-bearing component during tensile loading, where the orientation of the collagen fibres plays an important role for the tendon

  14. Increased unilateral tendon stiffness and its effect on gait 2-6 years after Achilles tendon rupture.

    PubMed

    Agres, A N; Duda, G N; Gehlen, T J; Arampatzis, A; Taylor, W R; Manegold, S

    2015-12-01

    Achilles tendon rupture (ATR) alters tissue composition, which may affect long-term tendon mechanics and ankle function during movement. However, a relationship between Achilles tendon (AT) properties and ankle joint function during gait remains unclear. The primary hypotheses were that (a) post-ATR tendon stiffness and length differ from the noninjured contralateral side and that (b) intra-patient asymmetries in AT properties correlate to ankle function asymmetries during gait, determined by ankle angles and moments. Ultrasonography and dynamometry were used to assess AT tendon stiffness, strain, elongation, and rest length in both limbs of 20 ATR patients 2-6 years after repair. Three-dimensional ankle angles and moments were determined using gait analysis. Injured tendons exhibited increased stiffness, rest length, and altered kinematics, with higher dorsiflexion and eversion, and lower plantarflexion and inversion. Intra-patient tendon stiffness and tendon length ratios were negatively correlated to intra-patient ratios of the maximum plantarflexion moment and maximum dorsiflexion angle, respectively. These results suggest that after surgical ATR repair, higher AT stiffness, but not a longer AT, may contribute to deficits in plantarflexion moment generation. These data further support the claim that post-ATR tendon regeneration results in the production of a tissue that is functionally different than noninjured tendon.

  15. In-vitro tensile testing machine for vibration study of fresh rabbit Achilles tendon

    NASA Astrophysics Data System (ADS)

    Revel, Gian M.; Scalise, Alessandro; Scalise, Lorenzo; Pianosi, Antonella

    2001-10-01

    A lot of people, overall athletic one suffer from tendinitis or complete rupture of the Achilles tendon. This structure becomes inflamed and damaged mainly from a variety of mechanical forces and sometimes due to metabolic problems, such as diabetes or arthritis. Over the past three decades extensive studies have been performed on the structural and mechanical properties of Achilles tendon trying to explain the constitutive equations to describe and foresee tendon behavior. Among the various mechanical parameters, the vibrational behavior is also of interest. Several investigations are performed in order to study how the Achilles tendon vibrations influence the response of the muscle proprioception and human posture. The present article describes how in vitro tensile experiments can be performed, taking into account the need to simulate physiological condition of Achilles tendon and thus approaching some opened problems in the design of the experimental set-up. A new system for evaluating tendon vibrations by non contact techniques is proposed. Preliminary simple elongation tests are made extracting the main mechanical parameters: stress and strain at different fixed stretches, in order to characterize the tissue. Finally, a vibration study is made at each pretensioned tendon level evaluating the oscillating curves caused by a small hammer.

  16. Achilles tendon biomechanics in response to acute intense exercise.

    PubMed

    Joseph, Michael F; Lillie, Kurtis R; Bergeron, Daniel J; Cota, Kevin C; Yoon, Joseph S; Kraemer, William J; Denegar, Craig R

    2014-05-01

    Achilles tendinopathy is a common disorder and is more prevalent in men. Although differences in tendon mechanics between men and women have been reported, understanding of tendon mechanics in young active people is limited. Moreover, there is limited understanding of changes in tendon mechanics in response to acute exercise. Our purpose was to compare Achilles tendon mechanics in active young adult men and women at rest and after light and strenuous activity in the form of repeated jumping with an added load. Participants consisted of 17 men and 14 women (18-30 years) who were classified as being at least moderately physically active as defined by the International Physical Activity Questionnaire. Tendon force/elongation measures were obtained during an isometric plantarflexion contraction on an isokinetic dynamometer with simultaneous ultrasound imaging of the Achilles tendon approximate to the soleus myotendinous junction. Data were collected at rest, after a 10-minute treadmill walk, and after a fatigue protocol of 100 toe jumps performed in a Smith machine, with a load equaling 20% of body mass. We found greater tendon elongation, decreased stiffness, and lower Young's modulus only in women after the jumping exercise. Force and stress were not different between groups but decreased subsequent to the jumping exercise bout. In general, women had greater elongation and strain, less stiffness, and a lower Young's modulus during plantarflexor contraction. These data demonstrate differences in tendon mechanics between men and women and suggest a potential protective mechanism explaining the lower incidence of Achilles tendinopathy in women.

  17. Reconstruction of Kuwada grade IV chronic achilles tendon rupture by minimally invasive technique

    PubMed Central

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

    2016-01-01

    Background: Transfer of a flexor hallucis longus (FHL) tendon can not only reconstruct the Achilles tendon but also provide ischemic tendinous tissues with a rich blood supply to enhance wound healing. This retrospective study aims to investigate clinical outcomes in patients who underwent repair of Kuwada grade IV chronic Achilles tendon rupture with long hallucis longus tendons harvested using a minimally invasive technique. Materials and Methods: 35 patients who were treated for Kuwada grade IV Achilles tendon injuries from July 2006 to June 2011 were included in this retrospective study. The age ranged between 23 and 71 years. The duration from primary injury to surgery ranged from 29 days to 34 months (mean value, 137.6 days). All 35 patients had difficulties in lifting their calves. Thirty two were followed up for a mean 32.2 months (range 18–72 months), whereas three were lost to followup. Magnetic resonance imaging (MRI) showed that the tendon rupture gap ranged from 6.0 to 9.2 cm. During surgery, a 2.0 cm minor incision was made vertically in the medial plantar side of the midfoot, and a 1.5 cm minor transverse incision was made in the plantar side of the interphalangeal articulation of the great toe to harvest the FHL tendon, and the tendon was fixed to the calcaneus with suture anchors. Postoperative appearance and function were evaluated by physiotherapists based American Orthopedic Foot and Ankle Society-ankle and hindfoot score (AOFAS-AH), and Leppilahti Achilles tendon ratings. Results: Results were assessed in 32 patients. Except for one patient who suffered complications because of wound disruption 10 days after the operation, all other patients had primary wound healing, with 28 of 32 able to go up on their toes at last followup. The AOFAS-AH score was increased from preoperative (51.92 ± 7.08) points to (92.56 ± 6.71) points; Leppilahti Achilles tendon score was increased from preoperative (72.56 ± 7.43) to (92.58 ± 5.1). There were

  18. 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.

  19. [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.

  20. Biomechanical Evaluation of Posterior Cruciate Ligament Reconstruction With Quadriceps Versus Achilles Tendon Bone Block Allograft

    PubMed Central

    Forsythe, Brian; Haro, Marc S.; Bogunovic, Ljiljana; Collins, Michael J.; Arns, Thomas A.; Trella, Katie J.; Shewman, Elizabeth F.; Verma, Nikhil N.; Bach, Bernard R.

    2016-01-01

    Background: Long-term studies of posterior cruciate ligament (PCL) reconstruction suggest that normal stability is not restored in the majority of patients. The Achilles tendon allograft is frequently utilized, although recently, the quadriceps tendon has been introduced as an alternative option due to its size and high patellar bone density. Purpose/Hypothesis: The purpose of this study was to compare the biomechanical strength of PCL reconstructions using a quadriceps versus an Achilles allograft. The hypothesis was that quadriceps bone block allograft has comparable mechanical properties to those of Achilles bone block allograft. Study Design: Controlled laboratory study. Methods: Twenty-nine fresh-frozen cadaveric knees were assigned to 1 of 3 groups: (1) intact PCL, (2) PCL reconstruction with Achilles tendon allograft, or (3) PCL reconstruction with quadriceps tendon allograft. After reconstruction, all supporting capsular and ligamentous tissues were removed. Posterior tibial translation was measured at neutral and 20° external rotation. Each specimen underwent a preload, 2 cyclic loading protocols of 500 cycles, then load to failure. Results: Construct creep deformation was significantly lower in the intact group compared with both Achilles and quadriceps allograft (P = .008). The intact specimens reached the greatest ultimate load compared with both reconstructions (1974 ± 752 N, P = .0001). The difference in ultimate load for quadriceps versus Achilles allograft was significant (P = .048), with the quadriceps group having greater maximum force during failure testing. No significant differences were noted between quadriceps versus Achilles allograft for differences in crosshead excursion during cyclic testing (peak-valley [P-V] extension stretch), creep deformation, or stiffness. Construct stiffness measured during the failure test was greatest in the intact group (117 ± 9 N/mm, P = .0001) compared with the Achilles (43 ± 11 N/mm) and quadriceps (43

  1. [Functional analysis after Achilles tendon repair].

    PubMed

    Moretti, B; Quagliarella, L; Sasanelli, N; Garofalo, R; Moretti, L; Patella, S; Belgiovine, G; Patella, V

    2007-01-01

    The Achilles tendon rupture (ATR) is a severe injury and requires a surgical treatment which can result in functional impairment, limiting unprofessional sports activities. In order to evaluate this potential impairment 20 subjects (SG) who had received surgical treatment for ATR and 20 healthy subjects (CG) were required to execute vertical jump according to counter movement jump and squat jump protocol. For both groups the flying time (Tv) of each foot has been acquired, adopting accelerometric transducers positioned posteriorly at the level of malleolar axis. The SG's Tv is significantly lesser than the CG's one, demonstrating an inferior global performance respect to healthy people and the operated leg has a Tv 6% higher than the contralateral, while in the CG there are no statistical difference between the Tv of the limbs. For seven operated subjects Tv values are lesser than threshold values obtained from CG. For them sports activity which implies high and cyclic stress on the lower limbs could be dangerous. Functional evaluation, consequently, allow to assess impairments not differently estimable.

  2. Ultrasound Changes in Achilles Tendon and Gastrocnemius Medialis Muscle on Squat Eccentric Overload and Running Performance.

    PubMed

    Sanz-López, Fernando; Berzosa Sánchez, César; Hita-Contreras, Fidel; Cruz-Diaz, David; Martínez-Amat, Antonio

    2016-07-01

    Sanz-López, F, Berzosa Sánchez, C, Hita-Contreras, F, Cruz-Diaz, D, and Martínez-Amat, A. Ultrasound changes in Achilles tendon and gastrocnemius medialis muscle on squat eccentric overload and running performance. J Strength Cond Res XX(X): 000-000, 2015-Previous studies have proven the adaptation to load in the Achilles tendon and gastrocnemius muscle after different types of exercise, such as running, heel drop training, and a variety of sports. These findings have been applied to improve performance and in the treatment and prevention of overuse injuries. However, the effects that squat performance may have on the Achilles tendon and gastrocnemius muscle are still unknown. Squats are a widely used training exercise that involves calf-muscle activation. Similarly, no reports have been published regarding the adaptation to load of trained and untrained subjects during several consecutive days of running. The purpose of this study was to analyze changes in the Achilles tendon and in the pennation angles of the gastrocnemius medialis after eccentric overload training and within 3 days of running. Twenty healthy males who volunteered for this study were divided into 2 groups. Subjects in the eccentric overload training (ECC) group performed 6 weeks of eccentric overload training (twice weekly, 4 sets of 7 repetitions in a Yoyo squat device) before the running intervention. All participants, ECC and control (CONT) groups, ran on 3 consecutive days. After the eccentric training, an increase in the cross-sectional area of the Achilles tendon and in the pennation angle was observed. As for the running intervention, the behavior of tissues in both groups was similar. These results suggest that eccentric overload training with squats promotes changes in the Achilles tendon and in the pennation angle of the gastrocnemius medialis muscle. Nevertheless, significant changes in the tissue do not appear between the running performance of trained and untrained subjects.

  3. Human hamstring tenocytes survive when seeded into a decellularized porcine Achilles tendon extracellular matrix.

    PubMed

    Lohan, Anke; Stoll, Christiane; Albrecht, Marit; Denner, Andreas; John, Thilo; Krüger, Kay; Ertel, Wolfgang; Schulze-Tanzil, Gundula

    2013-01-01

    Tendon ruptures and defects remain major orthopaedic challenges. Tendon healing is a time-consuming process, which results in scar tissue with an altered biomechanical competence. Using a xenogeneic tendon extracellular matrix (ECM) as a natural scaffold, which can be reseeded with autologous human tenocytes, might be a promising approach to reconstruct damaged tendons. For this purpose, the porcine Achilles (AS) tendons serving as a scaffold were histologically characterized in comparison to human cell donor tendons. AS tendons were decellularized and then reseeded with primary human hamstring tenocytes using cell centrifuging, rotating culture and cell injection techniques. Vitality testing, histology and glycosaminoglycan/DNA quantifications were performed to document the success of tendon reseeding. Porcine AS tendons were characterized by a higher cell and sulfated glycosaminoglycan content than human cell donor tendons. Complete decellularization could be achieved, but led to a wash out of sulfated glycosaminoglycans. Nevertheless, porcine tendon could be recellularized with vital human tenocytes. The recellularization led to a slight increase in cell number compared to the native tendon and some glycosaminoglycan recovery. This study indicates that porcine tendon can be de- and recellularized using adult human tenocytes. Future work should optimize cell distribution within the recellularized tendon ECM and consider tendon- and donor species-dependent differences.

  4. 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.

  5. Crimp morphology in relaxed and stretched rat Achilles tendon.

    PubMed

    Franchi, Marco; Fini, Milena; Quaranta, Marilisa; De Pasquale, Viviana; Raspanti, Mario; Giavaresi, Gianluca; Ottani, Vittoria; Ruggeri, Alessandro

    2007-01-01

    Fibrous extracellular matrix of tendon is considered to be an inextensible anatomical structure consisting of type I collagen fibrils arranged in parallel bundles. Under polarized light microscopy the collagen fibre bundles appear crimped with alternating dark and light transverse bands. This study describes the ultrastructure of the collagen fibrils in crimps of both relaxed and in vivo stretched rat Achilles tendon. Under polarized light microscopy crimps of relaxed Achilles tendons appear as isosceles or scalene triangles of different size. Tendon crimps observed via SEM and TEM show the single collagen fibrils that suddenly change their direction containing knots. The fibrils appear partially squeezed in the knots, bent on the same plane like bayonets, or twisted and bent. Moreover some of them lose their D-period, revealing their microfibrillar component. These particular aspects of collagen fibrils inside each tendon crimp have been termed 'fibrillar crimps' and may fulfil the same functional role. When tendon is physiologically stretched in vivo the tendon crimps decrease in number (46.7%) (P<0.01) and appear more flattened with an increase in the crimp top angle (165 degrees in stretched tendons vs. 148 degrees in relaxed tendons, P<0.005). Under SEM and TEM, the 'fibrillar crimps' are still present, never losing their structural identity in straightened collagen fibril bundles of stretched tendons even where tendon crimps are not detectable. These data suggest that the 'fibrillar crimp' may be the true structural component of the tendon crimp acting as a shock absorber during physiological stretching of Achilles tendon.

  6. Longitudinal Slit Procedure in Addition to Negative Pressure Wound Therapy for a Refractory Wound With Exposed Achilles Tendon

    PubMed Central

    Ohata, Erika; Mishima, Yoshito; Matsuo, Kiyoshi

    2015-01-01

    Objective: This case report reviews features of negative pressure wound therapy, particularly for the exposed Achilles tendon, and describes an additional effective procedure. Methods: An 87-year-old man presented with a soft-tissue defect measuring 3×5 cm with the exposed Achilles tendon as a sequela of deep burn. The condition of his affected leg was ischemic because of arteriosclerosis. We used negative pressure wound therapy and made 2 longitudinal slits penetrating the tendon to induce blood flow from the ventral side to the dorsal surface. Results: By this combination therapy, the surface of the exposed Achilles tendon was completely epithelialized and the tendon was spared without disuse syndrome. Conclusions: The authors conclude that this combination therapy is useful for covering the widely exposed tendon in aged patients. PMID:25848445

  7. Subject-specific finite element analysis to characterize the influence of geometry and material properties in Achilles tendon rupture.

    PubMed

    Shim, Vickie B; Fernandez, Justin W; Gamage, Prasad B; Regnery, Camille; Smith, David W; Gardiner, Bruce S; Lloyd, David G; Besier, Thor F

    2014-11-28

    Achilles tendon injuries including rupture are one of the most frequent musculoskeletal injuries, but the mechanisms for these injuries are still not fully understood. Previous in vivo and experimental studies suggest that tendon rupture mainly occurs in the tendon mid-section and predominantly more in men than women due to reasons yet to be identified. Therefore we aimed to investigate possible mechanisms for tendon rupture using finite element (FE) analysis. Specifically, we have developed a framework for generating subject-specific FE models of human Achilles tendon. A total of ten 3D FE models of human Achilles tendon were generated. Subject-specific geometries were obtained using ultrasound images and a mesh morphing technique called Free Form Deformation. Tendon material properties were obtained by performing material optimization that compared and minimized difference in uniaxial tension experimental results with model predictions. Our results showed that both tendon geometry and material properties are highly subject-specific. This subject-specificity was also evident in our rupture predictions as the locations and loads of tendon ruptures were different in all specimens tested. A parametric study was performed to characterize the influence of geometries and material properties on tendon rupture. Our results showed that tendon rupture locations were dependent largely on geometry while rupture loads were more influenced by tendon material properties. Future work will investigate the role of microstructural properties of the tissue on tendon rupture and degeneration by using advanced material descriptions.

  8. Biomechanical properties of Achilles tendon repair augmented with a bioadhesive-coated scaffold

    PubMed Central

    Brodie, Michael; Vollenweider, Laura; Murphy, John L; Xu, Fangmin; Lyman, Arinne; Lew, William D; Lee, Bruce P

    2011-01-01

    The Achilles tendon is the most frequently ruptured tendon. Both acute and chronic (neglected) tendon ruptures can dramatically affect a patient’s quality of life, and require a prolonged period of recovery before return to pre-injury activity levels. This paper describes the use of an adhesive-coated biologic scaffold to augment primary suture repair of transected Achilles tendons. The adhesive portion consisted of a synthetic mimic of mussel adhesive proteins that can adhere to various surfaces in a wet environment, including biologic tissues. When combined with biologic scaffolds such as bovine pericardium or porcine dermal tissues, these adhesive constructs demonstrated lap shear adhesive strengths significantly greater than that of fibrin glue, while reaching up to 60% of the strength of a cyanoacrylate-based adhesive. These adhesive constructs were wrapped around transected cadaveric porcine Achilles tendons repaired with a combination of parallel and three-loop suture patterns. Tensile mechanical testing of the augmented repairs exhibited significantly higher stiffness (22–34%), failure load (24–44%), and energy to failure (27–63%) when compared to control tendons with suture repair alone. Potential clinical implications of this novel adhesive biomaterial are discussed. PMID:21266745

  9. Compression therapy promotes proliferative repair during rat Achilles tendon immobilization.

    PubMed

    Schizas, Nikos; Li, Jian; Andersson, Therese; Fahlgren, Anna; Aspenberg, Per; Ahmed, Mahmood; Ackermann, Paul W

    2010-07-01

    Achilles tendon ruptures are treated with an initial period of immobilization, which obstructs the healing process partly by a reduction of blood circulation. Intermittent pneumatic compression (IPC) has been proposed to enhance tendon repair by stimulation of blood flow. We hypothesized that daily IPC treatment can counteract the deficits caused by 2 weeks of immobilization post tendon rupture. Forty-eight Sprague-Dawley SD) rats, all subjected to blunt Achilles tendon transection, were divided in three equal groups. Group A was allowed free cage activity, whereas groups B-C were immobilized at the operated hindleg. Group C received daily IPC treatment. Two weeks postrupture the rats were euthanatized and the tendons analyzed with tensile testing and histological assessments of collagen organization and collagen III-LI occurrence. Immobilization significantly reduced maximum force, energy uptake, stiffness, tendon length, transverse area, stress, organized collagen diameter and collagen III-LI occurrence by respectively 80, 75, 77, 22, 47, 65, 49, and 83% compared to free mobilization. IPC treatment improved maximum force 65%, energy 168%, organized collagen diameter 50%, tendon length 25%, and collagen III-LI occurrence 150% compared to immobilization only. The results confirm that immobilization impairs healing after tendon rupture and furthermore demonstrate that IPC-treatment can enhance proliferative tendon repair by counteracting biomechanical and morphological deficits caused by immobilization.

  10. One-stage treatment of deep infection following repair of Achilles tendon rupture with flexor hallucis longus transfer.

    PubMed

    Lee, Kang; Moon, Jeong Seok; Seo, Jeong Gook; Lee, Woo Chun

    2009-03-01

    We present one-stage treatment of deep infection following repair of Achilles tendon rupture using flexor hallucis longus transfer. Flexor hallucis longus was used not only to connect the defect in Achillles tendon, but also to control the soft tissue infection with its abundant blood supply, simultaneously. The clinical results for the two patients in this report were excellent without major complication.

  11. Modeling the tensile behavior of human Achilles tendon.

    PubMed

    Lewis, G; Shaw, K M

    1997-01-01

    Uniaxial quasi-static tensile stress, sigma versus strain, epsilon, data were obtained from 29 cadaveric Achilles tendons (donor ages: 36 to 100 years), at a strain rate of either 10 or 100%/s. These results were then used in modeling the elastic component of the tensile deformational behavior of this tissue. Two approaches were taken. In the first, it was shown that the following constitutive relation provided an excellent fit to the elastic section of the sigma-epsilon curve, sigma = C epsilon exp[D epsilon + F epsilon 2], with C, D and F being material constants, whose values for the present dataset were found to be C = 2.00 +/- 0.99, D = 0.089 +/- 0.087 and F = -0.0047 +/- 0.0095. The values of these coefficients were not statistically significantly affected by either donor age or test strain rate. In the second approach, the value of the modulus of elasticity of a filamentary polymer matrix composite material was computed as a function of various combinations of values of the modulus of elasticity of the fiber, the modulus of elasticity of the matrix, and angle of orientation of the principal material axes with respect to the reference coordinate axes (theta) for a fiber volume fraction of 0.6 and a material Poisson's ratio of 0.4. By comparing these results with the experimentally-obtained values of the tangent modulus of elasticity of the tendons (defined as the slope of the linear section of the post-toe zone in the sigma-epsilon plot), and assuming that the tendon may be idealized as a filamentary polymer matrix composite material, the suggestion is made that the winding angle of the fibers (collagen fibrils) in the tendon (taken to be equal to theta) is about 6 degrees.

  12. Changes in the Achilles tendon reflexes following Skylab missions

    NASA Technical Reports Server (NTRS)

    Baker, J. T.; Nicogossian, A. E.; Hoffler, G. W.; Johnson, R. L.; Hordinsky, J. R.

    1977-01-01

    Postflight measurements of Achilles tendon reflex duration on Skylab crewmen indicate a state of disequilibrium between the flexor and extensor muscle groups with an initial decrease in reflex duration. As the muscles regain strength and mass there occurs an overcompensation reflected by increased reflex duration. Finally, when a normal neuromuscular state is reached the reflex duration returns to baseline value.

  13. Heel pain and Achilles tendonitis -- aftercare

    MedlinePlus

    ... walking or standing on your foot References Achilles Tendinitis. In: Safran MR, Zachazewski J, Stone DA, eds. ... Related MedlinePlus Health Topics Heel Injuries and Disorders Tendinitis Browse the Encyclopedia A.D.A.M., Inc. ...

  14. [Treatment of traumatic sections of the Achilles tendon].

    PubMed

    Orfanu, N

    1977-01-01

    The author maintains that the atrophy of the sural triceps muscle, the retraction of the Achille tendon and the osteoporosis of the calcaneum and of the tarsian bones, occurring after the traumatic sectioning of the Achille tendon, are the results of an inadequate treatment. The cause of these sequellae is the immobilization of the foot in an equinus position, which relaxes the sural triceps and as a result of the lack of mechanical traction factor, leads to local circulatory disturbances followed by a modification in the structure of the bone and of the muscle. On the basis of this pathophysiological concept the author has excluded post-operative immobilization in the equinus position, and in fact any type of immobilization, recommending in contrast a mobilization of the foot from the very first days after the suture of the tendon. The clinical results obtained confirm the value of the hypothesis.

  15. The Effect of Sodium Hyaluronate on Ligamentation and Biomechanical Property of Tendon in Repair of Achilles Tendon Defect with Polyethylene Terephthalate Artificial Ligament: A Rabbit Tendon Repair Model

    PubMed Central

    Li, Shengkun; Jiang, Jia; Chen, Shiyi

    2016-01-01

    The Achilles tendon is the most common ruptured tendon of human body. Reconstruction with polyethylene terephthalate (PET) artificial ligament is recommended in some serious cases. Sodium hyaluronate (HA) is beneficial for the healing of tendon injuries. We aimed to determine the effect of sodium hyaluronate in repair of Achilles tendon defect with PET artificial ligament in an animal tendon repair model. Sixteen New Zealand White rabbits were divided into two groups. Eight rabbits repaired with PET were assigned to PET group; the other eight rabbits repaired with PET along with injection of HE were assigned to HA-PET group. All rabbits were sacrificed at 4 and 8 weeks postoperatively for biomechanical and histological examination. The HA-PET group revealed higher biomechanical property compared with the PET group. Histologically, more collagen tissues grew into the HA-PET group compared with PET group. In conclusion, application of sodium hyaluronate can improve the healing of Achilles tendon reconstruction with polyethylene terephthalate artificial ligament. PMID:28105436

  16. Experimental diabetes induces structural, inflammatory and vascular changes of Achilles tendons.

    PubMed

    de Oliveira, Rodrigo R; Martins, Conceição S; Rocha, Yuri R; Braga, Allysson B R; Mattos, Rômulo M; Hecht, Fábio; Brito, Gerly A C; Nasciutti, Luiz E

    2013-01-01

    This study aims to demonstrate how the state of chronic hyperglycemia from experimental Diabetes Mellitus can influence the homeostatic imbalance of tendons and, consequently, lead to the characteristics of tendinopathy. Twenty animals were randomly divided into two experimental groups: control group, consisting of healthy rats and diabetic group constituted by rats induced to Diabetes Mellitus I. After twenty-four days of the induction of Diabetes type I, the Achilles tendon were removed for morphological evaluation, cellularity, number and cross-sectional area of blood vessel, immunohistochemistry for Collagen type I, VEGF and NF-κB nuclear localization sequence (NLS) and nitrate and nitrite level. The Achilles tendon thickness (µm/100g) of diabetic animals was significantly increased and, similarly, an increase was observed in the density of fibrocytes and mast cells in the tendons of the diabetic group. The average number of blood vessels per field, in peritendinous tissue, was statistically higher in the diabetic group 3.39 (2.98) vessels/field when compared to the control group 0.89 (1.68) vessels/field p = 0.001 and in the intratendinous region, it was observed that blood vessels were extremely rare in the control group 0.035 (0.18) vessels/field and were often present in the tendons of the diabetic group 0.89 (0.99) vessels/field. The immunohistochemistry analysis identified higher density of type 1 collagen and increased expression of VEGF as well as increased immunostaining for NFκB p50 NLS in the nucleus in Achilles tendon of the diabetic group when compared to the control group. Higher levels of nitrite/nitrate were observed in the experimental group induced to diabetes. We conclude that experimental DM induces notable structural, inflammatory and vascular changes in the Achilles tendon which are compatible with the process of chronic tendinopathy.

  17. Toilet seat injury of the Achilles tendon a series of twelve cases.

    PubMed

    Dar, Tahir Ahmed; Sultan, Asif; Dhar, Shabir Ahmed; Ali, Murtaza Fazal; Wani, Mohammed Iqbal; Wani, Sharief Ahmed

    2011-12-01

    Lacerations of the Achilles tendon are caused by a number of mechanisms. The toilet seat as a cause of Achilles tendon injury is rare. We report on this rare mechanism of laceration of the tendo Achilles. The injury can be avoided with the use of western toilets and the additional devascularisation caused by extending the wound should be avoided while repairing the tendon in such situations.

  18. A study of the Achilles tendon while running

    PubMed Central

    ANIŢAŞ, RĂZVAN; LUCACIU, DAN

    2013-01-01

    The following study attempts to elaborate a model of the Achilles tendon while in the process of running, specifically during a step that is part of a running sequence. Data are collected with the help of a force plate and then is processed and modeled to serve as a starting point and comparison to a mathematical model using polynomial functions. The data collected were filtered to diminish recording of “noise” and an empirical model was established. Mathematical models using second order and fourth order polynomials were employed, as well as an approximation using known maximal force. The increase in the accuracy of modeling was determined as the order of the polynomial function increased. Achieving an accurate predictor function is essential in understanding the biomechanics of the Achilles tendon. PMID:26527913

  19. Variation in the human Achilles tendon moment arm during walking.

    PubMed

    Rasske, Kristen; Thelen, Darryl G; Franz, Jason R

    2017-02-01

    The Achilles tendon (AT) moment arm is an important determinant of ankle moment and power generation during locomotion. Load and depth-dependent variations in the AT moment arm are generally not considered, but may be relevant given the complex triceps surae architecture. We coupled motion analysis and ultrasound imaging to characterize AT moment arms during walking in 10 subjects. Muscle loading during push-off amplified the AT moment arm by 10% relative to heel strike. AT moment arms also varied by 14% over the tendon thickness. In walking, AT moment arms are not strictly dependent on kinematics, but exhibit important load and spatial dependencies.

  20. Modulation of soleus corticospinal excitability during Achilles tendon vibration.

    PubMed

    Lapole, Thomas; Temesi, John; Arnal, Pierrick J; Gimenez, Philippe; Petitjean, Michel; Millet, Guillaume Y

    2015-09-01

    Soleus (SOL) corticospinal excitability has been reported to increase during Achilles tendon vibration. The aim of the present study was to further investigate SOL corticospinal excitability and elucidate the changes to intracortical mechanisms during Achilles tendon vibration. Motor-evoked potentials (MEPs) were elicited in the SOL by transcranial magnetic stimulation (TMS) of the corresponding motor cortical area of the leg with and without 50-Hz Achilles tendon vibration. SOL input-output curves were determined. Paired-pulse protocols were also performed to investigate short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) by conditioning test TMS pulses with sub-threshold TMS pulses at inter-stimulus intervals of 3 and 13 ms, respectively. During Achilles tendon vibration, motor threshold was lower than in the control condition (43 ± 13 vs. 49 ± 11 % of maximal stimulator output; p = 0.008). Input-output curves were also influenced by vibration, i.e. there was increased maximal MEP amplitude (0.694 ± 0.347 vs. 0.268 ± 0.167 mV; p < 0.001), decreased TMS intensity to elicit a MEP of half the maximal MEP amplitude (100 ± 13 vs. 109 ± 9 % motor threshold; p = 0.009) and a strong tendency for decreased slope constant (0.076 ± 0.04 vs. 0.117 ± 0.04; p = 0.068). Vibration reduced ICF (98 ± 61 vs. 170 ± 105 % of test MEP amplitude; p = 0.05), but had no effect on SICI (53 ± 26 vs. 48 ± 22 % of test MEP amplitude; p = 0.68). The present results further document the increased vibration-induced corticospinal excitability in the soleus muscle and suggest that this increase is not mediated by changes in SICI or ICF.

  1. 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

  2. [Achilles tendon rupture--early functional and surgical options with special emphasis on rehabilitation issues].

    PubMed

    Knobloch, K; Thermann, H; Hüfner, T

    2007-03-01

    Achilles tendon ruptures are one end of a continuum starting with the healthy Achilles tendon via the thickened and painful tendinopathic Achilles tendon with neovascularisation to the complete tendon rupture. Often times chinolone antibiotics, cortisone therapy and valgus foot axis are associated risk factors. Incidence of Achilles tendon ruptures is estimated to be 10/100 000 per year with a mean age of 35-40 years. Physical activity is encountered in 75 % cases of Achilles tendon ruptures. Running is associated with Achilles tendinopathy as the predominant overuse injury in an analysis among 291 athletes with 10 million kilometers exposure. The Achilles tendinopathic rate was 0.016/1000 km differentiated in 0.008/1000 km mid-portion tendinopathy and 0.005/1000 km insertional tendinopathy. Achilles tendinopathy in running overuse injuries is followed by runner's knee (0.013/1000 km), shin splint (0.0104/1000 km) and plantar fasciitis (0.0054/1000 km). Dynamic ultrasound in 20 degrees plantar flexion is of utmost importance for therapeutic decision making. With an adaptation rate of 75 % or more of the ruptured tendon in 20 degrees plantar flexion and a high patient's compliance we perform an early functional conservative treatment regimen in Achilles tendon ruptures. In almost all other cases the percutaneous Achilles tendon repair is indicated, where nervus suralis lesions have to be appreciated. The vulnerable zone is 10-12 cm proximal to the calcaneus at the lateral border of the Achilles tendon with the sural nerve in close proximity with the tendon. Early functional rehabilitation is not associated with a higher risk of rerupture but with improved subjective assessments and should therefore be advocated.

  3. Adverse reactions of Achilles tendon xanthomas in three hypercholesterolemic patients after treatment intensification with niacin and bile acid sequestrants.

    PubMed

    Lakey, Wanda C; Greyshock, Nicole; Guyton, John R

    2013-01-01

    Multiple cholesterol-reducing therapies have been shown to induce the regression of tendon xanthoma in patients with familial hypercholesterolemia. We present 3 cases of adverse reactions in Achilles tendon xanthomas after the addition of niacin and bile acid sequestrants to ongoing statin therapy. Reduction in tendon dimensions and marked softening of xanthomas were interpreted as cholesterol removal from heavily infiltrated tissue sites. In 2 cases, changes in the xanthomas occurred despite only minor lipoprotein improvements, raising the possibility of direct drug effects in cholesterol-infiltrated tissue. Intriguingly, recent studies have described niacin receptor-mediated effects in macrophages. In summary, although adverse reactions in Achilles tendon xanthomas appear to be infrequent, clinicians should be aware of this phenomenon in their patients after intensifying lipid treatments, especially with the use of niacin in patients with familial hypercholesterolemia. Xanthoma responses may provide clues to new pharmacologic effects in cholesterol-infiltrated tissues.

  4. A Prospective Study of Platelet-Rich Plasma as Biological Augmentation for Acute Achilles Tendon Rupture Repair

    PubMed Central

    Zou, Jian; Mo, Xiaolian; Li, Tanzhu; Xue, Jianfeng; Mei, Guohua; Li, Xiaolin

    2016-01-01

    Acute Achilles tendon rupture is one of the most common tendon injuries in adults. We hypothesized that Platelet-Rich Plasma (PRP) can be used as biological augmentation for surgical treatment of acute Achilles tendon rupture. Our study is a prospective randomized controlled trial. Patients with acute Achilles tendon rupture undergoing surgical repair were randomly assigned into either control group or PRP group. End-to-end modified Krackow suture was performed in both groups. In the PRP group, PRP was injected into the paratenon sheath and around the ruptured tissue after the tendon was repaired. Postoperatively we evaluated isokinetic muscle strength at 3, 6, 12, and 24 months. In addition, ankle ROM, calf circumference, Leppilahti score, and the SF-36 score were evaluated at 6, 12, and 24 months after operation. At 3 months, the PRP group had better isokinetic muscle. The PRP group also achieved higher SF-36 and Leppilahti scores at 6 and 12 months. At 24 months, the PRP group had an improved ankle range of motion compared to the control group. Our study results suggest that PRP can serve as a biological augmentation to acute Achilles tendon rupture repair and improves both short and midterm functional outcomes. PMID:28116306

  5. In vivo evaluation of the elastic anisotropy of the human Achilles tendon using shear wave dispersion analysis

    NASA Astrophysics Data System (ADS)

    Brum, J.; Bernal, M.; Gennisson, J. L.; Tanter, M.

    2014-02-01

    Non-invasive evaluation of the Achilles tendon elastic properties may enhance diagnosis of tendon injury and the assessment of recovery treatments. Shear wave elastography has shown to be a powerful tool to estimate tissue mechanical properties. However, its applicability to quantitatively evaluate tendon stiffness is limited by the understanding of the physics on the shear wave propagation in such a complex medium. First, tendon tissue is transverse isotropic. Second, tendons are characterized by a marked stiffness in the 400 to 1300 kPa range (i.e. fast shear waves). Hence, the shear wavelengths are greater than the tendon thickness leading to guided wave propagation. Thus, to better understand shear wave propagation in tendons and consequently to properly estimate its mechanical properties, a dispersion analysis is required. In this study, shear wave velocity dispersion was measured in vivo in ten Achilles tendons parallel and perpendicular to the tendon fibre orientation. By modelling the tendon as a transverse isotropic viscoelastic plate immersed in fluid it was possible to fully describe the experimental data (deviation<1.4%). We show that parallel to fibres the shear wave velocity dispersion is not influenced by viscosity, while it is perpendicularly to fibres. Elasticity (found to be in the range from 473 to 1537 kPa) and viscosity (found to be in the range from 1.7 to 4 Pa.s) values were retrieved from the model in good agreement with reported results.

  6. Stretching for prevention of Achilles tendon injuries: a review of the literature.

    PubMed

    Park, Don Young; Chou, Loretta

    2006-12-01

    Professional and recreational athletes commonly perform pre-exercise stretching to prevent musculoskeletal injuries. Little definitive evidence exists that clearly demonstrates the efficacy of stretching in reducing injury. Achilles tendon injuries are among the most common injuries affecting active individuals in the United States today. Clinicians commonly recommend stretching the Achilles tendon without concrete scientific evidence to support such a claim. Few studies have addressed the effect of stretching in Achilles tendon injuries, and it is unclear if the conclusions made for musculoskeletal injuries can be applied to the Achilles tendon. Biomechanical studies of the Achilles tendon and measurements of the tendon's reflex activity have demonstrated possible mechanisms for the potential benefit of stretching, including load-induced hypertrophy and increased tendon tensile strength. Recent prospective studies have contended that reductions in plantarflexor strength and increases in ankle dorsiflexion range of motion from stretching the Achilles tendon may increase the risk of injury. Studies examining stretching in injury prevention, the biomechanical properties of injuries to the Achilles tendon were compiled and reviewed. Although many theories have been published regarding the potential benefits and limitations of stretching, few studies have been able to definitively demonstrate its utility in injury prevention.

  7. [Repair of Achilles tendon rupture and early rehabilitation].

    PubMed

    Delgado-Brambila, H A; Cristiani, D G; Tinajero, E C; Burgos-Elías, V

    2012-01-01

    The frequency of Achilles tendon tear has increased worldwide. Several factors have been described that help explain the mechanism of injury. The treatment of choice continues to be surgery; conservative treatment is reserved for patients with a high morbidity and mortality. Surgical treatment consists of an open or percutaneous technique. In both modalities we try to achieve prompt mobilization of the operated tendon to obtain better and quicker healing. This prospective study describes our experience with 35 patients enrolled from February 2004 to August 2010. They were treated with open repair, physical rehabilitation and active ankle mobilization before the second postoperative week, and with colchicine. We obtained satisfactory results. Patients recovered complete mobility approximately at postoperative week 6, and from weeks 8 to 10 they could resume their daily work activities and participate in sports and recreational activities. Patients were assessed according to the ATRS classification to measure their clinical results. We had no infections or other major complications. We conclude that the open surgical repair of Achilles tendon tear, prompt mobility, and colchicine provide good results.

  8. Management of achilles tendon injury: A current concepts systematic review

    PubMed Central

    Gulati, Vivek; Jaggard, Matthew; Al-Nammari, Shafic Said; Uzoigwe, Chika; Gulati, Pooja; Ismail, Nizar; Gibbons, Charles; Gupte, Chinmay

    2015-01-01

    Achilles tendon rupture has been on the rise over recent years due to a variety of reasons. It is a debilitating injury with a protracted and sometimes incomplete recovery. Management strategy is a controversial topic and evidence supporting a definite approach is limited. Opinion is divided between surgical repair and conservative immobilisation in conjunction with functional orthoses. A systematic search of the literature was performed. Pubmed, Medline and EmBase databases were searched for Achilles tendon and a variety of synonymous terms. A recent wealth of reporting suggests that conservative regimens with early weight bearing or mobilisation have equivalent or improved rates of re-rupture to operative regimes. The application of dynamic ultrasound assessment of tendon gap may prove crucial in minimising re-rupture and improving outcomes. Studies employing functional assessments have found equivalent function between operative and conservative treatments. However, no specific tests in peak power, push off strength or athletic performance have been reported and whether an advantage in operative treatment exists remains undetermined. PMID:25992315

  9. Achilles detachment in rat and stable gastric pentadecapeptide BPC 157: Promoted tendon-to-bone healing and opposed corticosteroid aggravation.

    PubMed

    Krivic, Andrija; Anic, Tomislav; Seiwerth, Sven; Huljev, Dubravko; Sikiric, Predrag

    2006-05-01

    Stable gastric pentadecapeptide BPC 157 (BPC 157, as an antiulcer agent in clinical trials for inflammatory bowel disease; PLD-116, PL 14736, Pliva, no toxicity reported) alone (without carrier) ameliorates healing of tendon and bone, respectively, as well as other tissues. Thereby, we focus on Achilles tendon-to-bone healing: tendon to bone could not be healed spontaneously, but it was recovered by this peptide. After the rat's Achilles tendon was sharply transected from calcaneal bone, agents [BPC 157 (10 microg, 10 ng, 10 pg), 6alpha-methylprednisolone (1 mg), 0.9% NaCl (5 mL)] were given alone or in combination [/kg body weight (b.w.) intraperitoneally, once time daily, first 30-min after surgery, last 24 h before analysis]. Tested at days 1, 4, 7, 10, 14, and 21 after Achilles detachment, BPC 157 improves healing functionally [Achilles functional index (AFI) values substantially increased], biomechanically (load to failure, stiffness, and Young elasticity modulus significantly increased), macro/microscopically, immunohistochemistry (better organization of collagen fibers, and advanced vascular appearance, more collagen type I). 6alpha-Methylprednisolone consistently aggravates the healing, while BPC 157 substantially reduces 6alpha-methylprednisolone healing aggravation. Thus, direct tendon-to-bone healing using stabile nontoxic peptide BPC 157 without a carrier might successfully exchange the present reconstructive surgical methods.

  10. Percutaneous Achilles tendon repair with and without endoscopic control.

    PubMed

    Halasi, Tamás; Tállay, András; Berkes, István

    2003-11-01

    One hundred and fifty six patients were treated using the modified double suture technique for percutaneous Achilles tendon repair between 1994 and 1998. Endoscopy was used in 67 cases. The first ten cases were dropped (learning curve), 57 were followed (E-group). Percutaneous suture without endoscopy was performed in 89 patients. Two could not be followed (went abroad), so this group consists of 87 patients (P-group). Mean age: E-group 37.8 (22-60) years, P-group 38.9 (20-68) years. Male-female ratio: E 49/8, P 74/13. There were 54 and 83 athletes in groups E and P respectively. Follow-up period was 12-60 months. Overall re-rupture rate was 6/144 (4.2%). Two total and 3 partial re-ruptures were in the P-group, and 1 partial was in the E-group. Fusiform thickening of the tendon (delayed healing) occurred in 4 cases in each group. The mean plantar flexion strength compared with the non-affected side was 89% in the P-group and 86% in the E-group. The length of time before returning to sports activity ranged from 4 to 6 months after surgery in both groups. Subjective results were excellent to good in 88% (P-group) and in 89% (E-group) of the cases. On the basis of the results, the percutaneous double suture technique proved to be a simple and safe method for Achilles tendon repair with or without the use of an endoscope. The re-rupture rate was lower in the endoscopic controlled group. The basic goal of the endoscopy was to control the adaptation of the tendon ends. This method yielded further operative possibilities and benefits as well.

  11. Incidence and outcome of rupture of the Achilles tendon.

    PubMed

    Cretnik, Andrej; Frank, Aleksander

    2004-01-01

    We determined the incidence of complete rupture of the Achilles tendon in the Maribor region (273,609 inhabitants) between 1991 and 1996. During this period, 116 ruptures were treated at Maribor Teaching Hospital. The average incidence was 7 ruptures per 100,000 inhabitants, with a peak incidence of almost 9 per 100,000. Most injuries (65%) occurred during sports activities, with soccer as the major cause of rupture. The average age of patients was 37 years with a male-to-female ratio of 18:1. All patients underwent open surgical repair of the ruptured Achilles tendon, with a minimum follow-up of two years. 19.8% of cases developed complications and in 10.4% of these the complications were major. 1.9% of patients sustained a re-rupture. The mean AOFAS score was 96 points. The patients were subjectively very satisfied with their treatment in 88% of cases. Good functional results with a return to the usual pre-injury activities were achieved in 96% of patients.

  12. Effect of Calendula officinalis cream on achilles tendon healing.

    PubMed

    Aro, A A; Perez, M O; Vieira, C P; Esquisatto, M A M; Rodrigues, R A F; Gomes, L; Pimentel, E R

    2015-02-01

    In recent years, the scientific community has undertaken research on plant extracts, searching for compounds with pharmacological activities that can be used in diverse fields of medicine. Calendula officinalis L. is known to have antioxidant, anti-inflammatory, antibacterial, and wound healing properties when used to treat skin burns. Therefore, the purpose of this study was to analyze the effects of C. officinalis on the initial phase of Achilles tendon healing. Wistar rats were separated in three groups: Calendula (Cal)-rats with a transected tendon were treated with topical applications of C. officinalis cream and then euthanized 7 days after injury; Control (C)-rats were treated with only vehicle after transection; and Normal (N)-rats without tenotomy. Higher concentrations of hydroxyproline (an indicator of total collagen) and non-collagenous proteins were observed in the Cal group in relation to the C group. Zymography showed no difference in the amount of the isoforms of metalloproteinase-2 and of metalloproteinase-9, between C and Cal groups. Polarization microscopy images analysis showed that the Cal group presented a slightly higher birefringence compared with the C group. In sections of tendons stained with toluidine blue, the transected groups presented higher metachromasy as compared with the N group. Immunocytochemistry analysis for chondroitin-6-sulfate showed no difference between the C and Cal groups. In conclusion, the topical application of C. officinalis after tendon transection increases the concentrations of collagen and non-collagenous proteins, as well as the collagen organization in the initial phase of healing.

  13. 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

  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. Mycobacterium fortuitum infection following primary achilles tendon debridement with flexor hallucis longus augmentation: a case report.

    PubMed

    Jacoby, Sidney M; Sivalingam, Jocelyn J; Raikin, Steven Mark

    2008-05-01

    Mycobacterium fortuitum (M. fortuitum), a rapidly growing non-tuberculous mycobacterium is a well-recognized, yet uncommon cause of soft tissue infection. The incidence of post surgical wound infections from this organism is increasing. The presentation of infection is atypical and failure to consider this pathogen can cause diagnostic delay and increased morbidity. Achilles tendon debridement with FHL augmentation is commonly used in patients with chronic Achilles tendinosis. Wound-edge necrosis is the most common surgical complication of this procedure, and superficial and deep infections are potentially devastating complications. We report the case of a patient who underwent Achilles tendon debridement with flexor hallucis longus augmentation, whose postoperative course was complicated by a deep M. FORTUITUM infection. Critical to the identification and ultimate treatment of this particular pathogen is the utilization of appropriate intraoperative cultures and microbiologic testing. In addition, repeat aggressive irrigation and debridement procedures coupled with removal of foreign materials and the appropriate use of prolonged antibiotic therapy can result in a successful long-term outcome.

  16. Patellofemoral Joint and Achilles Tendon Loads During Overground and Treadmill Running.

    PubMed

    Willy, Richard W; Halsey, Lisa; Hayek, Andrew; Johnson, Holly; Willson, John D

    2016-08-01

    Study Design Level 4, controlled laboratory study. Background Little is known regarding how the potential differences between treadmill and overground running may affect patellofemoral joint and Achilles tendon loading characteristics. Objectives To compare measures of loading of the patellofemoral joint and Achilles tendon across treadmill and overground running in healthy, uninjured runners. Methods Eighteen healthy runners ran at their self-selected speed on an instrumented treadmill and overground, while 3-D running mechanics were sampled. A musculoskeletal model derived peak load, rate of loading, and estimated cumulative load per 1 km of continuous running for the patellofemoral joint and Achilles tendon for each condition. Data were analyzed via paired t tests and Pearson correlations to detect differences and assess relationships, respectively, between the 2 running mediums. Results No differences (P>.05) were found between treadmill and overground running for peak load, rate of loading, or estimated cumulative patellofemoral joint stress per 1 km of continuous running. However, treadmill running resulted in 12.5% greater peak Achilles tendon force (P<.001), 15.6% greater loading rate of Achilles tendon force (P<.001), and 14.2% greater estimated cumulative Achilles tendon force per 1 km of continuous running (P<.001) compared with overground running. There were strong (r>0.70) and moderate agreements (r>0.50) for most patellofemoral joint and Achilles measures, respectively, between treadmill and overground running. Conclusion No differences were observed in loading characteristics to the patellofemoral joint between running mediums; however, treadmill running resulted in greater Achilles tendon loading compared with overground running. Future investigations should examine whether sudden bouts of treadmill running may increase the risk of mechanical overload of the Achilles tendon in runners who habitually train overground. J Orthop Sports Phys Ther 2016

  17. Concurrent deficits of soleus and gastrocnemius muscle fascicles and Achilles tendon post stroke.

    PubMed

    Zhao, Heng; Ren, Yupeng; Roth, Elliot J; Harvey, Richard L; Zhang, Li-Qun

    2015-04-01

    Calf muscles and Achilles tendon play important roles in functional activities. However, it is not clear how biomechanical properties of the uniarticular soleus (SOL) and biarticular gastrocnemius muscle and Achilles tendon, including the fascicle length, pennation angle, and stiffness, change concurrently post stroke. Biomechanical properties of the medial gastrocnemius (GM) and soleus muscles were evaluated bilaterally in 10 hemiparetic stroke survivors using combined ultrasonography-biomechanical measurements. Biomechanical properties of the Achilles tendon including the length, cross-sectional area (CSA), stiffness, and Young's modulus were evaluated, together with calf muscle biomechanical properties. Gastrocnemius and SOL contributions were separated using flexed and extended knee positions. The impaired side showed decreased fascicle length (GM: 6%, P = 0.002 and SOL: 9%, P = 0.03, at full knee extension and 0° ankle dorsiflexion) and increased fascicular stiffness (GM: 64%, P = 0.005 and SOL: 19%, P = 0.012, at a common 50 N force level). In contrast, Achilles tendon on the impaired side showed changes in the opposite direction as the muscle fascicles with increased tendon length (5%, P < 0.001), decreased tendon CSA (5%, P = 0.04), decreased tendon stiffness (42%, P < 0.001) and Young's modulus (30%, P < 0.001) compared with the unimpaired side. The fascicle and tendon stiffness changes were correlated negatively to the corresponding fascicle and tendon length changes, and decrease in Achilles tendon stiffness was correlated to the increases of SOL and GM fascicular stiffness (P < 0.05). Characterizations of calf muscle fascicles and Achilles tendon biomechanical properties help us better understand concurrent changes of fascicles and tendon as part of the calf muscle-tendon unit and facilitate development of more effective treatments.

  18. 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.

  19. 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.

  20. Dual Fixation of Calcaneal Tuberosity Avulsion with Concomitant Achilles Tendon Rupture: A Novel Hybrid Technique

    PubMed Central

    Kusnezov, Nicholas; Rensing, Nicholas

    2017-01-01

    Fracture of the calcaneal tuberosity with a concomitant Achilles tendon rupture presents a difficult challenge for the treating surgeon. The ultimate goal of treatment is to restore function of both the gastrocnemius-soleus complex and the Achilles tendon. This particular subset of fractures occurs often in diabetics and elderly patients with osteoporosis making fixation of the displaced fragment rather complex. If the Achilles tendon disruption is only discovered later once the fracture is healed, subsequent management is difficult with surgical treatment being more morbid. While this is a rare injury, the consequences of a missed chronic Achilles tendon disruption are severe with significant dysfunction. It is therefore important to have a high index of suspicion for concomitant injury and to be prepared for dual fixation. We present a novel hybrid surgical fixation technique, which may be used in this instance. PMID:28357147

  1. Tendon mineralization is accelerated bilaterally and creep of contralateral tendons is increased after unilateral needle injury of murine achilles tendons.

    PubMed

    O'Brien, Etienne John Ogilvy; Shrive, Nigel G; Rosvold, Joshua M; Thornton, Gail M; Frank, Cyril B; Hart, David A

    2013-10-01

    Heterotopic mineralization may result in tendon weakness, but effects on other biomechanical responses have not been reported. We used a needle injury, which accelerates spontaneous mineralization of murine Achilles tendons, to test two hypotheses: that injured tendons would demonstrate altered biomechanical responses; and that unilateral injury would accelerate mineralization bilaterally. Mice underwent left hind (LH) injury (I; n = 11) and were euthanized after 20 weeks along with non-injured controls (C; n = 9). All hind limbs were examined by micro computed tomography followed by biomechanical testing (I = 7 and C = 6). No differences were found in the biomechanical responses of injured tendons compared with controls. However, the right hind (RH) tendons contralateral to the LH injury exhibited greater static creep strain and total creep strain compared with those LH tendons (p ≤ 0.045) and RH tendons from controls (p ≤ 0.043). RH limb lesions of injured mice were three times larger compared with controls (p = 0.030). Therefore, despite extensive mineralization, changes to the responses we measured were limited or absent 20 weeks postinjury. These results also suggest that bilateral occurrence should be considered where tendon mineralization is identified clinically. This experimental system may be useful to study the mechanisms of bilateral new bone formation in tendinopathy and other conditions.

  2. Statins induce biochemical changes in the Achilles tendon after chronic treatment.

    PubMed

    de Oliveira, Letícia Prado; Vieira, Cristiano Pedrozo; Da Ré Guerra, Flávia; de Almeida, Marcos dos Santos; Pimentel, Edson Rosa

    2013-09-15

    Statins have been widely prescribed as lipid-lowering drugs and are associated with tendon rupture. Therefore, this study aimed to evaluate the possible biochemical changes in the Achilles tendon of rats after chronic treatment with statins. Dosages of statins were calculated using allometric scaling with reference to the 80mg/day and 20mg/day, doses recommended for humans. The rats were divided into the following groups: treated with simvastatin (S-20 and S-80), treated with atorvastatin (A-20 and A-80), and the control group that received no treatment (C). Measurements of low-density lipoprotein (LDL) in the plasma were performed. The levels of non-collagenous proteins, glycosaminoglycans (GAGs) and hydroxyproline were quantified. Western blotting for collagen I was performed, and the presence of metalloproteinases (MMPs)-2 and -9 was investigated through zymography. The concentration of non-collagenous proteins in S-20 was less than the C group. There was a significant increase in pro-MMP-2 activity in A-80 group and in active MMP-2 in S-20 group compared to the C group. A significant increase in latent MMP-9 activity was observed in both the A-80 and S-20 groups when compared to C group. In the A-20 group, there was a lower amount of collagen I in relation to C group. In addition, a higher concentration of hydroxyproline was found in the S-20 group than the C group. The analysis of GAGs showed a significant increase in the A-20 group when compared to C group. The treatment induced remarkable alterations in the Achilles tendon and the response of the tissue seems to depend of the used statin dosage. The presence of MMP-2 and MMP-9 is evidence of the degradation and remodeling processes in the extracellular matrix of the tendons. Our results show that statins induce imbalance of extracellular matrix components and possibly induce microdamage in tendons.

  3. Evaluation of Elastic Stiffness in Healing Achilles Tendon After Surgical Repair of a Tendon Rupture Using In Vivo Ultrasound Shear Wave Elastography

    PubMed Central

    Zhang, Li-ning; Wan, Wen-bo; Wang, Yue-xiang; Jiao, Zi-yu; Zhang, Li-hai; Luo, Yu-kun; Tang, Pei-fu

    2016-01-01

    Background There has been no published report assessing the mechanical properties of a repaired Achilles tendon after surgery using shear wave elastography (SWE). The aim of this study was to investigate the changes in mechanical properties of the healing Achilles tendon after surgical repair of a tendon rupture using ultrasound SWE and how these changes correlate with tendon function. Material/Methods Twenty-six patients who underwent surgical repair for Achilles tendon rupture were examined with ultrasound SWE coupled with a linear array transducer (4–15 MHz). The elasticity values of the repaired Achilles tendon in a longitudinal view were measured at 12, 24, and 48 weeks postoperatively. Functional outcomes were assessed with the American Orthopedic Foot and Ankle Society (AOFAS) rating system at 12, 24, and 48 weeks postoperatively. General linear regression analysis and correlation coefficients were used to analyze the relationship between elasticity and the AOFAS score. Results There were significant differences with respect to the mean elasticity values and functional scores of the repaired Achilles tendon at 12, 24, and 48 weeks postoperatively (all P<0.05). Tendon function was positively correlated with the elasticity of the repaired Achilles tendon (P=0.0003). Conclusions Our findings suggest that SWE can provide biomechanical information for evaluating the mechanical properties of healing Achilles tendon and predict Achilles tendon function. PMID:27072885

  4. Age-related differences in Achilles tendon properties and triceps surae muscle architecture in vivo.

    PubMed

    Stenroth, Lauri; Peltonen, Jussi; Cronin, Neil J; Sipilä, Sarianna; Finni, Taija

    2012-11-01

    This study examined the concurrent age-related differences in muscle and tendon structure and properties. Achilles tendon morphology and mechanical properties and triceps surae muscle architecture were measured from 100 subjects [33 young (24 ± 2 yr) and 67 old (75 ± 3 yr)]. Motion analysis-assisted ultrasonography was used to determine tendon stiffness, Young's modulus, and hysteresis during isometric ramp contractions. Ultrasonography was used to measure muscle architectural features and size and tendon cross-sectional area. Older participants had 17% lower (P < 0.01) Achilles tendon stiffness and 32% lower (P < 0.001) Young's modulus than young participants. Tendon cross-sectional area was also 16% larger (P < 0.001) in older participants. Triceps surae muscle size was smaller (P < 0.05) and gastrocnemius medialis muscle fascicle length shorter (P < 0.05) in old compared with young. Maximal plantarflexion force was associated with tendon stiffness and Young's modulus (r = 0.580, P < 0.001 and r = 0.561, P < 0.001, respectively). Comparison between old and young subjects with similar strengths did not reveal a difference in tendon stiffness. The results suggest that regardless of age, Achilles tendon mechanical properties adapt to match the level of muscle performance. Old people may compensate for lower tendon material properties by increasing tendon cross-sectional area. Lower tendon stiffness in older subjects might be beneficial for movement economy in low-intensity locomotion and thus optimized for their daily activities.

  5. Achilles tendon reattachment after surgical treatment of insertional tendinosis using the suture bridge technique: a case series.

    PubMed

    Witt, Bryan L; Hyer, Christopher F

    2012-01-01

    Achilles tendinopathy is a clinical diagnosis characterized as a triad of symptoms including pain, swelling, and impaired performance of the diseased tendon. Achilles tendinopathy is divided into Achilles tendonitis and tendinosis based on histopathological examination. Achilles tendinosis is viewed microscopically as disorganized collagen, abnormal neovascularization, necrosis, and mucoid degeneration. Insertional Achilles tendinosis is a degenerative process of the tendon at the junction of the tendon and calcaneus. This disease is initially treated conservatively with activity modification, custom orthotic devices, heel lifts, and immobilization. After 3 to 6 months of conservative therapy has failed to alleviate symptoms, surgical management is indicated. Surgical management of insertional Achilles tendinosis includes Achilles tendon debridement, calcaneal exostosis ostectomy, and retrocalcaneal bursa excision. In this case series, we present 4 patients who underwent surgical management of insertional Achilles tendinosis with complete tendon detachment. All patients underwent reattachment of the Achilles tendon with the suture bridge technique. The Arthrex SutureBridge(®) (Arthrex, Inc., Naples, FL) device uses a series of 4 suture anchors and FiberWire(®) (Arthrex Inc.) to reattach the Achilles tendon to its calcaneal insertion. This hourglass pattern of FiberWire(®) provides a greater area of tendon compression, consequently allowing greater stability and possible earlier return to weightbearing activities. The patients were followed up for approximately 2 years' duration. There were no intraoperative or postoperative complications. At final follow-up there was no evidence of Achilles tendon ruptures or device failures. All patients were able to return to their activities of daily living without the use of assistive devices. The patients' average visual analog pain scale was 1 (range 0 to 4), and their average foot functional index score was 3.41 (range 0

  6. 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.

  7. Imaging and simulation of Achilles tendon dynamics: Implications for walking performance in the elderly.

    PubMed

    Franz, Jason R; Thelen, Darryl G

    2016-06-14

    The Achilles tendon (AT) is a complex structure, consisting of distinct fascicle bundles arising from each triceps surae muscle that may act as mechanically independent structures. Advances in tissue imaging are rapidly accelerating our understanding of the complexities of functional Achilles tendon behavior, with potentially important implications for musculoskeletal injury and performance. In this overview of our recent contributions to these efforts, we present the results of complementary experimental and computational approaches to investigate AT behavior during walking and its potential relevance to reduced triceps surae mechanical performance due to aging. Our experimental evidence reveals that older tendons exhibit smaller differences in tissue deformations than young adults between regions of the AT presumed to arise from the gastrocnemius and soleus muscles. These observations are consistent with a reduced capacity for inter-fascicle sliding within the AT, which could have implications for the mechanical independence of the triceps surae muscles. More uniform AT deformations are also correlated with hallmark biomechanical features of elderly gait - namely, a loss of net ankle moment, power, and positive work during push-off. Simulating age-related reductions in the capacity for inter-fascicle sliding in the AT during walking predicts detriments in gastrocnemius muscle-tendon mechanical performance coupled with underlying shifts in fascicle kinematics during push-off. AT compliance, also suspected to vary due to age, systematically modulates those effects. By integrating in vivo imaging with computational modeling, we have gained theoretical insight into multi-scale biomechanical changes due to aging, hypotheses regarding their functional effects, and opportunities for experiments that validate or invalidate these assertions.

  8. Positional effects of the knee and ankle on the ends of acute Achilles tendon ruptures.

    PubMed

    Wray, Walter H; Regan, Conor; Patel, Sagar; May, Ryan; Parekh, Selene G

    2009-10-01

    Conservative management of acute Achilles tendon ruptures in a plantarflexed short leg cast or functional brace is a viable alternative to surgery. The ideal plantarflexion angle to allow the free ends of the tendon to oppose one another has not been clearly defined. The purpose of this cadaveric study was to define a plantarflexion angle where the free Achilles tendon ends reliably oppose one another. Ten cadaveric legs amputated at the distal femur were obtained. A laceration of the Achilles tendon was made 4 cm above the calcaneal insertion. A joint-spanning external fixator was placed across the knee. With differing degrees of knee flexion (0, 45, and 90 degrees), the diastasis between the free ends of the Achilles tendon was measured as the ankle was moved from 20 degrees of dorsiflexion to 30 degrees of plantarflexion (-20, -10, neutral, 10, 20, and 30 degrees). Regardless of knee flexion angle, the ankle plantarflexion angle where the free ends of the Achilles tendon opposed one another was 28.0 (95% confidence interval: 25.0-33.6) degrees. The ideal ankle angle in which to immobilize patients appears tightly clustered around 28 degrees of plantarflexion.

  9. Use of Platelet Rich Plasma and Hyaluronic Acid in the Treatment of Complications of Achilles Tendon Reconstruction

    PubMed Central

    Gentile, Pietro; De Angelis, Barbara; Agovino, Annarita; Orlandi, Fabrizio; Migner, Alessandra; Di Pasquali, Camilla; Cervelli, Valerio

    2016-01-01

    BACKGROUND The platelet-rich plasma (PRP) and hyaluronic acid (HA) constitute a system of tissue growth that can regenerate damaged tissue. This study was performed to evaluate the effect of PRP and HA in treatment of complications of Achilles tendon reconstruction. METHODS We selected ten patients affected by Achilles tendon injuries resulting from post-surgical complications subsequent to tenorrhaphy and have treated them with autologous PRP in combination with HA to evaluate the improvement of lesions with wound closure. RESULTS The treatment with PRP and HA for post-surgical complications of Achilles tendon was effective in healing and regeneration of soft and hard tissues. The healing time was shortened, and the treated area preserved a satisfying strength in plantar flexion and extension of the ankle, denoting to a decisive improvement in texture and a more rapid healing and a good cutaneous elasticity, with a significant reduction of the costs of hospitalization and the pain already the immediate postoperatively. The functional rehabilitation in terms of deambulation and joint mobility was complete. CONCLUSION The treatment we proposed allowed an easier and more rapid wound closure with excellent aesthetic improvement. Furthermore, the minimally invasive technique is well tolerated by patients. PMID:27579267

  10. Minimally invasive flexor hallucis longus transfer in management of acute achilles tendon rupture associated with tendinosis: a case report.

    PubMed

    Lui, Tun Hing

    2012-04-01

    Chronic tendinopathy is characterized by pain in the tendon, generally at the start and completion of exercise. However, tendinosis may lead to decreased blood flow, increased stiffness of the tendon and reduced tensile strength, and predispose to rupture. Operative treatment is indicated to restore the function of the Achilles tendon and alleviate the prerupture heel cord pain. A case of acute Achilles tendon rupture with extensive tendinosis that was successfully treated with minimally invasive flexor hallucis longus transfer is reported.

  11. Regional molecular and cellular differences in the female rabbit Achilles tendon complex: potential implications for understanding responses to loading.

    PubMed

    Huisman, Elise S; Andersson, Gustav; Scott, Alexander; Reno, Carol R; Hart, David A; Thornton, Gail M

    2014-05-01

    The aim of this study was: (i) to analyze the morphology and expression of extracellular matrix genes in six different regions of the Achilles tendon complex of intact normal rabbits; and (ii) to assess the effect of ovariohysterectomy (OVH) on the regional expression of these genes. Female New Zealand White rabbits were separated into two groups: (i) intact normal rabbits (n = 4); and (ii) OVH rabbits (n = 8). For each rabbit, the Achilles tendon complex was dissected into six regions: distal gastrocnemius (DG); distal flexor digitorum superficialis; proximal lateral gastrocnemius (PLG); proximal medial gastrocnemius; proximal flexor digitorum superficialis; and paratenon. For each of the regions, hematoxylin and eosin staining was performed for histological evaluation of intact normal rabbit tissues and mRNA levels for proteoglycans, collagens and genes associated with collagen regulation were assessed by real-time reverse transcription-quantitative polymerase chain reaction for both the intact normal and OVH rabbit tissues. The distal regions displayed a more fibrocartilaginous phenotype. For intact normal rabbits, aggrecan mRNA expression was higher in the distal regions of the Achilles tendon complex compared with the proximal regions. Collagen Type I and matrix metalloproteinase-2 expression levels were increased in the PLG compared to the DG in the intact normal rabbit tissues. The tendons from OVH rabbits had lower gene expressions for the proteoglycans aggrecan, biglycan, decorin and versican compared with the intact normal rabbits, although the regional differences of increased aggrecan expression in distal regions compared with proximal regions persisted. The tensile and compressive forces experienced in the examined regions may be related to the regional differences found in gene expression. The lower mRNA expression of the genes examined in the OVH group confirms a potential effect of systemic estrogen on tendon.

  12. Achilles tendon injury in kendo players in junior and senior high schools: with a focus on foot function

    PubMed Central

    Kisi, Shinya; Yoshida, Munehito

    2017-01-01

    [Purpose] We investigated Achilles tendon injury in Kendo players in junior and senior high schools to obtain a possible indicator for preventing an outbreak of Achilles tendon injury and tendonitis, possible risk factors concerning foot function and morphology were extracted. [Subjects and Methods] The subjects were 60 Kendo players aged 14–18 years from Wakayama Prefecture, Japan (33 boys and 27 girls). A questionnaire survey was conducted on the past history, current status, time of occurrence about Achilles tendon pain or rupture, and site of Achilles tendon pain or rupture. Based on the responses to the questionnaire, these students were divided into two groups, i.e., those who had a history of Achilles tendon pain (n=30) or rupture (n=3) (pain group) and those who had no history of Achilles tendon pain (no-pain group), and they were examined for foot alignment, flexion and extension Range of motion test of the first toe, flexion and extension muscle strength of the first toe, and opening movement of the toes. [Results] Achilles tendon pain had occurred in 53% of the Kendo players (including 3 who had suffered Achilles tendon rupture). Poor foot alignment and deterioration of opening movement of the toes were noted in the pain group. [Conclusion] Foot alignment was poor and opening function of the toes deteriorated in the pain group, suggesting that these may be some of factors for Achilles tendon injury. Training aimed at improving foot alignment and function is important to prevent and improve Achilles tendon injury. PMID:28265159

  13. Gene targeting of the transcription factor Mohawk in rats causes heterotopic ossification of Achilles tendon via failed tenogenesis

    PubMed Central

    Suzuki, Hidetsugu; Ito, Yoshiaki; Shinohara, Masahiro; Yamashita, Satoshi; Ichinose, Shizuko; Kishida, Akio; Oyaizu, Takuya; Kayama, Tomohiro; Nakamichi, Ryo; Koda, Naoki; Yagishita, Kazuyoshi; Lotz, Martin K.; Okawa, Atsushi; Asahara, Hiroshi

    2016-01-01

    Cell-based or pharmacological approaches for promoting tendon repair are currently not available because the molecular mechanisms of tendon development and healing are not well understood. Although analysis of knockout mice provides many critical insights, small animals such as mice have some limitations. In particular, precise physiological examination for mechanical load and the ability to obtain a sufficient number of primary tendon cells for molecular biology studies are challenging using mice. Here, we generated Mohawk (Mkx)−/− rats by using CRISPR/Cas9, which showed not only systemic hypoplasia of tendons similar to Mkx−/− mice, but also earlier heterotopic ossification of the Achilles tendon compared with Mkx−/− mice. Analysis of tendon-derived cells (TDCs) revealed that Mkx deficiency accelerated chondrogenic and osteogenic differentiation, whereas Mkx overexpression suppressed chondrogenic, osteogenic, and adipogenic differentiation. Furthermore, mechanical stretch stimulation of Mkx−/− TDCs led to chondrogenic differentiation, whereas the same stimulation in Mkx+/+ TDCs led to formation of tenocytes. ChIP-seq of Mkx overexpressing TDCs revealed significant peaks in tenogenic-related genes, such as collagen type (Col)1a1 and Col3a1, and chondrogenic differentiation-related genes, such as SRY-box (Sox)5, Sox6, and Sox9. Our results demonstrate that Mkx has a dual role, including accelerating tendon differentiation and preventing chondrogenic/osteogenic differentiation. This molecular network of Mkx provides a basis for tendon physiology and tissue engineering. PMID:27370800

  14. Suture-Only Repair Versus Suture Anchor–Augmented Repair for Achilles Tendon Ruptures With a Short Distal Stump

    PubMed Central

    Boin, Michael A.; Dorweiler, Matthew A.; McMellen, Christopher J.; Gould, Gregory C.; Laughlin, Richard T.

    2017-01-01

    Background: Chronic noninsertional Achilles tendinosis can result in an acute Achilles tendon rupture with a short distal stump. In such tendon ruptures, there is a limited amount of adequate tissue that can hold suture, thus presenting a challenge for surgeons who elect to treat the rupture operatively. Hypothesis: Adding suture anchors to the repair construct may result in biomechanically stronger repairs compared with a suture-only technique. Study Design: Controlled laboratory study. Methods: Nine paired Achilles-calcaneus complexes were harvested from cadavers. An artificial Achilles rupture was created 2 cm proximal to the insertion on the calcaneus. One specimen from each cadaver was assigned to a suture-only or a suture anchor–augmented repair. The contralateral specimen of the same cadaver received the opposing repair. Cyclic testing was then performed at 10 to 100 N for 2000 cycles, and load-to-failure testing was performed at 0.2 mm/s. This was followed by analysis of repair displacement, gapping at repair site, peak load to failure, and failure mode. Results: The suture anchor–augmented repair exhibited a 116% lower displacement compared with the suture-only repair (mean ± SD, 1.54 ± 1.13 vs 3.33 ± 1.47 mm, respectively; P < .03). The suture anchor–augmented repair also exhibited a 45% greater load to failure compared with the suture-only repair (303.50 ± 102.81 vs 209.09 ± 48.12 N, respectively; P < .04). Conclusion: Suture anchor–augmented repairs performed on acute Achilles tendon ruptures with a short distal stump are biomechanically stronger than suture-only repairs. Clinical Relevance: Our results support the use of suture anchor–augmented repairs for a biomechanically stronger construct in Achilles tendon ruptures with a short distal stump. Biomechanically stronger repairs may lead to less tendon repair gapping and failure, increasing the ability to start early active rehabilitation protocols and thus improving patient outcomes

  15. Changes induced by ozone and ultraviolet light in type I collagen. Bovine Achilles tendon collagen versus rat tail tendon collagen.

    PubMed

    Fujimori, E

    1985-10-15

    High-molecular-mass aggregates were made soluble from insoluble collagens of bovine Achilles tendon and rat tail tendon by limited thermal hydrolysis. These polymeric collagen aggregates were cross-linked by 390-nm-fluorescent 3-hydroxy-pyridinium residues (excited at 325 nm) in the former tendon and by unknown non-fluorescent residues in the latter. With the solubilized insoluble-collagens from both tendons, as well as with acid-soluble collagen from rat tail tendon, other 350-385-nm fluorescence intensities (excited at 300 nm) were found to be higher in monomeric chains than in dimeric and polymeric chains. Low levels of ozone inhibited fibril formation of acid-soluble collagen particularly from young rat tail tendon, reacting with tyrosine residues and the 350-385-nm fluorophores. Aldehyde groups, involved in cross-linking, were not effectively modified by ozone. beta-Components (alpha-chain dimers) were not efficiently dissociated even by higher doses of ozone compared to gamma-components (alpha-chain trimers). Polymeric chain aggregates from bovine Achilles tendon collagen, whose 3-hydroxy-pyridinium cross-links are cleaved by ozone, were more readily dissociated by ozone than those from rat tail tendon collagen. Ultraviolet (300-nm) light, which destroyed the 350-385-nm fluorophores, inhibited fibril formation less effectively than ultraviolet (275-nm) light, which is absorbed by tyrosine residues, and did not dissociate collagen polymers from rat tail tendon. On the other hand, ultraviolet (320-nm) light, absorbed by 3-hydroxy-pyridinium cross-links which were rapidly photolyzed, partially dissociated polymeric collagen aggregates from bovine Achilles tendon after subsequent heating.

  16. 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.

  17. Ultrasound strain mapping of Achilles tendon compressive strain patterns during dorsiflexion.

    PubMed

    Chimenti, Ruth L; Flemister, A Samuel; Ketz, John; Bucklin, Mary; Buckley, Mark R; Richards, Michael S

    2016-01-04

    Heel lifts are commonly prescribed to patients with Achilles tendinopathy, yet little is known about the effect on tendon compressive strain. The purposes of the current study were to (1) develop a valid and reliable ultrasound elastography technique and algorithm to measure compressive strain of human Achilles tendon in vivo, (2) examine the effects of ankle dorsiflexion (lowering via controlled removal of a heel lift and partial squat) on compressive strain of the Achilles tendon insertion and (3) examine the relative compressive strain between the deep and superficial regions of the Achilles tendon insertion. All tasks started in a position equivalent to standing with a 30mm heel lift. An ultrasound transducer positioned over the Achilles tendon insertion was used to capture radiofrequency images. A non-rigid image registration-based algorithm was used to estimate compressive strain of the tendon, which was divided into 2 regions (superficial, deep). The bland-Altman test and intraclass correlation coefficient were used to test validity and reliability. One-way repeated measures ANOVA was used to compare compressive strain between regions and across tasks. Compressive strain was accurately and reliably (ICC>0.75) quantified. There was greater compressive strain during the combined task of lowering and partial squat compared to the lowering (P=.001) and partial squat (P<.001) tasks separately. There was greater compressive strain in the deep region of the tendon compared to the superficial for all tasks (P=.001). While these findings need to be examined in a pathological population, heel lifts may reduce tendon compressive strain during daily activities.

  18. 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

  19. [Impingement lesion of the distal anterior Achilles tendon in sub-Achilles bursitis and Haglund-pseudoexostosis-a therapeutic challenge].

    PubMed

    Lohrer, H; Arentz, S

    2003-12-01

    Retrocalcaneal bursitis in athletes is frequently misdiagnosed. Results of conservative treatment are not very promising. This investigation evaluates the results of 39 consecutive cases in 38 patients surgically treated due to chronic retrokalkaneal bursitis in a sport specific population. Preoperative MRI and ultrasound investigation showed corresponding lesions (focal degeneration, partial rupture) of the anterior Achilles tendon. This is possibly the result of a previously undescribed impingement lesion produced by the Haglund's bone and the chronically inflamed retrocalcaneal bursa. During operation this lesion was additionally addressed in 85% of the cases. Follow up was done after 32 months. Success rate was 54%. VISA-A Score at follow up was 80.6 points. Training and competition activities were started at 16 weeks and 9 months respectively. Unsatisfying results were analysed. In two cases Haglund's bone resection was incomplete and had to be removed in a reoperation. Additionally one deep wound infection had to be revised. Due to the distal Achilles tendon fiber extensions around the medial and lateral calcaneal bone, an unintended Achilles tendon lesion, induced by the edge of the osteotome seems to be possible. Two calcanear stress fractures complicated the postoperative rehabilitation.

  20. New Imaging Methods for Non-invasive Assessment of Mechanical, Structural, and Biochemical Properties of Human Achilles Tendon: A Mini Review

    PubMed Central

    Fouré, Alexandre

    2016-01-01

    The mechanical properties of tendon play a fundamental role to passively transmit forces from muscle to bone, withstand sudden stretches, and act as a mechanical buffer allowing the muscle to work more efficiently. The use of non-invasive imaging methods for the assessment of human tendon's mechanical, structural, and biochemical properties in vivo is relatively young in sports medicine, clinical practice, and basic science. Non-invasive assessment of the tendon properties may enhance the diagnosis of tendon injury and the characterization of recovery treatments. While ultrasonographic imaging is the most popular tool to assess the tendon's structural and indirectly, mechanical properties, ultrasonographic elastography, and ultra-high field magnetic resonance imaging (UHF MRI) have recently emerged as potentially powerful techniques to explore tendon tissues. This paper highlights some methodological cautions associated with conventional ultrasonography and perspectives for in vivo human Achilles tendon assessment using ultrasonographic elastography and UHF MRI. PMID:27512376

  1. Adaptive Remodeling of Achilles Tendon: A Multi-scale Computational Model

    PubMed Central

    Rubenson, Jonas; Umberger, Brian

    2016-01-01

    While it is known that musculotendon units adapt to their load environments, there is only a limited understanding of tendon adaptation in vivo. Here we develop a computational model of tendon remodeling based on the premise that mechanical damage and tenocyte-mediated tendon damage and repair processes modify the distribution of its collagen fiber lengths. We explain how these processes enable the tendon to geometrically adapt to its load conditions. Based on known biological processes, mechanical and strain-dependent proteolytic fiber damage are incorporated into our tendon model. Using a stochastic model of fiber repair, it is assumed that mechanically damaged fibers are repaired longer, whereas proteolytically damaged fibers are repaired shorter, relative to their pre-damage length. To study adaptation of tendon properties to applied load, our model musculotendon unit is a simplified three-component Hill-type model of the human Achilles-soleus unit. Our model results demonstrate that the geometric equilibrium state of the Achilles tendon can coincide with minimization of the total metabolic cost of muscle activation. The proposed tendon model independently predicts rates of collagen fiber turnover that are in general agreement with in vivo experimental measurements. While the computational model here only represents a first step in a new approach to understanding the complex process of tendon remodeling in vivo, given these findings, it appears likely that the proposed framework may itself provide a useful theoretical foundation for developing valuable qualitative and quantitative insights into tendon physiology and pathology. PMID:27684554

  2. Outcome evaluation after Achilles tendon ruptures. A review of the literature

    PubMed Central

    SPENNACCHIO, PIETRO; VASCELLARI, ALBERTO; CUCCHI, DAVIDE; CANATA, GIAN LUIGI; RANDELLI, PIETRO

    2016-01-01

    The optimal treatment and the best rehabilitation protocol after an acute Achilles tendon rupture (ATR) remain a matter of controversy in orthopaedic and sports medicine. The use of validated injury-specific outcome instruments is the only way to clarify these issues, in order to ensure that patients receive the best possible treatment. This article describes the most commonly reported outcome measures used to assess patients treated for ATR. On the basis of the available evidence, the Achilles tendon Total Rupture Score (ATRS) is the most appropriate outcome measure for evaluating the management of acute ATR. PMID:27386448

  3. Surgery in the Standing Position by a Surgeon with Achilles Tendon Rupture.

    PubMed

    Yasuhara, Takao; Kuwahara, Ken; Sasada, Susumu; Toyoshima, Atsuhiko; Morimoto, Jun; Kin, Kyohei; Manabe, Hiroaki; Miyoshi, Yasuyuki; Kusumegi, Akira; Takahashi, Yuichi; Ito, Kiyoshi; Date, Isao

    2016-12-01

    Unexpected injuries can have a profound effect on a surgeon's performance and thus on patients and surgical departments. Here we describe a technique for performing surgery in the standing position, as done by a surgeon with an Achilles tendon rupture. During his prescribed 45-day non-weight-bearing period for the left ankle after surgery for an Achilles tendon rupture, the surgeon was able to participate in 15 surgeries as an operator or assistant, due to his use of a combination of injured-leg genuflection on a stool and a 'Surgical Body Support' device. Similarly injured surgeons may benefit from such support.

  4. [Atypical Achilles tendon rupture in Haglund exostosis--a case report].

    PubMed

    Porsch, M; Hackenbroch, M H; König, D P

    1998-01-01

    We report about an unusual case of a rupture of the Achilles tendon in a patient with Haglund's exostosis and long term achillodynia. Intraoperatively, we found a fresh superficial typically located tendon-rupture and an old deep round shaped rupture which was located directly over the cranial edge of the calcaneous bone spur. We presume that the sharp edge of Haglund's deformity was the cause of the deep tendon rupture, because the location of the round shaped rupture was near the exostosis. The additional superficial rupture, caused by an inadequate trauma, induced operative revision consisting of double layer transosseous suturing. In conclusion early operative resection of Haglund's deformity in cases of repeated irritations of the Achilles tendon should be performed to avoid mechanical damage, including the risk of rupture by the hypomochlion-like effect of the exostosis.

  5. [Operative treatment of extended peritendinous calcifications after open Achilles tendon repair-a case report].

    PubMed

    Kraus, R; Horas, U; Stahl, J-P; Schnettler, R

    2003-08-01

    In the recent literature, there are only a few hints on spontaneous or postoperative heterotopic ossifications of the Achilles tendon region. The strategies of treatment are different, both conservative and operative. Postoperative calcifications are not mentioned as typical complications in the treatment of Achilles tendon ruptures. We describe the case of a 39 year old male suffering of an increasing, painful swelling and a decrease of loading capacity. In clinical, sonographic and radiological investigations,we found large peritendinous calcifications ventral to the intact heel tendon up to 36 mm in diameter. After operative resection of the calcifications and postoperative chemical prophylaxis, the patient has been without pain for 1 year. There was no relapse of the calcifications or re-rupture of the tendon.

  6. Complete Achilles tendon rupture after local infiltration of corticosteroids in the treatment of deep retrocalcaneal bursitis.

    PubMed

    Vallone, Ganfranco; Vittorio, Tarallo

    2014-06-01

    Complete rupture of the Achilles tendon is relatively rare, but it is an injury of considerable clinical relevance. A common cause of non-traumatic tendon rupture is local corticosteroid infiltration. Corticosteroid injections may start a degenerative process resulting in partial rupture and subsequent complete rupture of the tendon due to a direct toxic effect, because corticosteroids inhibit production of extracellular matrix collagen and also because of poor local vascularization. This paper describes the case of a patient who presented with complete rupture of the Achilles tendon shortly after administration of local corticosteroid injections in the treatment of deep retrocalcaneal bursitis. This confirms that corticosteroid treatment which is not correctly and accurately administered may be a factor contributing to major injury. It demonstrates that the physician must take all necessary precautions when administering corticosteroid infiltration. It is particularly important that corticosteroid injection is performed under ultrasound guidance which permits visualization of the needle tip and therefore exact identification of the injection site.

  7. Effects of estrogen on the mechanical behavior of the human Achilles tendon in vivo.

    PubMed

    Bryant, Adam L; Clark, Ross A; Bartold, Simon; Murphy, Aron; Bennell, Kim L; Hohmann, Erik; Marshall-Gradisnik, Sonya; Payne, Craig; Crossley, Kay M

    2008-10-01

    The purpose of this study was to elucidate the effect of normal fluctuating [non-monophasic oral contraceptive pill (MOCP) users] and low, consistent (MOCP users) endogenous plasma estrogen levels on the strain behavior of the Achilles tendon in vivo. Twenty women (age 28.0 +/- 4.2 yr, height 1.67 +/- 0.07 m, mass 61.6 +/- 6.8 kg) who had been using the MOCP for at least 12 mo together with 20 matched women who were non-MOCP users (age 31.9 +/- 7.3 yr, height 1.63 +/- 0.05 m, mass 62.5 +/- 5.9 kg) participated in this study. Non-MOCP users were tested at the time of lowest (menstruation) and highest (approximately same as ovulation) estrogen, whereas MOCP users, who exhibited constant and attenuated endogenous estrogen levels, were tested at day 1 and day 14 of their cycle. At each test session, maximal isometric plantarflexion efforts were performed on a calf-raise apparatus while synchronous real-time ultrasonography of the triceps surae aponeurosis was recorded. Achilles tendon strain (%) was calculated by dividing tendon displacement during plantarflexion by resting tendon length. Repeated-measures ANOVA revealed a significant (P < 0.05) main effect of subject group with significantly lower Achilles strain (25.5%) in the MOCP users compared with the non-MOCP users. In conclusion, acute fluctuations in plasma estrogen across the menstrual cycle in non-MOCP users did not alter the strain behavior of the Achilles tendon. Conversely, long-term exposure to attenuated estrogen in MOCP users resulted in a decrease in Achilles tendon strain, which is thought to be attributed to the effects of endogenous estrogen on collagen synthesis. These findings have a number of important functional and clinical implications.

  8. New technical procedure involving Achilles tendon rupture treatment through transcutaneous suture.

    PubMed

    TarniŢă, DănuŢ Nicolae; TarniŢă, Daniela; Grecu, Dan Cristian; Calafeteanu, Dan Marian; Căpitănescu, Bogdan

    2016-01-01

    The Achilles tendon is the widest tendon of the human body. Achilles tendon belongs to the extrasynovial tendons group and this allows it a faster recovery, thanks to local hematoma from the peritenon, necessary for the scarification. We concluded that in Achilles tendon rupture treatment it is essential to maintain the tendon covering skin integrity, the peritendinous integrity, to maintain the local hematoma formed during and after tendon rupture, reattaching the ruptured tendon heads and maintain them in this position by suturing them and by relaxing the sural triceps muscle. The percutaneous suture requires five pairs of mirror micro-incisions (5 mm) on one side and the other of the tendon. It is necessary for one of the pairs to be placed to the rupture level. With a surgical needle, we arm the proximal and distal heads of the tendon by different threads. By traction and muscular relaxation, we bring in contact the two ruptured heads and then we knot together the arming threads. The inferior member was cast immobilized in relaxing position for the sural triceps muscle for a 45 days period. Using this technique, we have operated 15 cases in our Clinic. In all the cases, we obtained a healing by first intention of the tegument micro-incisions. After the cast immobilization suppression, during 30 days the patients were in a recovery program. At the end of this program, they have recovered completely the dorsal and plantar flexion and the walking. In four months after the surgery, the esthetic of the area is completely restored, this technique being the only surgical technique that realizes this recovery.

  9. A composite medial plantar flap for the repair of an achilles' tendon defect: a case report.

    PubMed

    Dumont, C E; Kessler, J

    2001-12-01

    The surgical management of infected necrosis of the Achilles' tendon and overlying skin is very demanding, and reconstruction with vascularized tendon and skin flaps is considered the benchmark procedure. The authors report a 65-year-old man who sustained a chronic wound after operative repair of a chronic rupture of the Achilles' tendon. A pedicled medial plantar flap including the surrounding vascularized plantar aponeurosis was elevated. The plantar aponeurosis was split and used to bridge the 4-cm-long tendon defect. The flap donor site was covered with a thin skin graft. The flap survived completely without recurrence of the infection. At the 7-month follow-up, the reconstructed Achilles' tendon showed a good functional result and a normal range of dorsi- and plantar flexion of the foot. This technique is of great interest in comparison with free flaps because it does not require vascular anastomosis in a septic environment or a secondary debulking operation, yet it still provides both vascularized tendon and skin graft.

  10. The influence of physical activity during youth on structural and functional properties of the Achilles tendon.

    PubMed

    Lenskjold, A; Kongsgaard, M; Larsen, J O; Nielsen, R H; Kovanen, V; Aagaard, P; Kjaer, M; Magnusson, S P

    2015-02-01

    Achilles tendinopathy is a highly prevalent sports injury. Animal studies show a growth response in tendons in response to loading in the immature phase but not after puberty maturation. The aim of this investigation was to examine the structural and material properties in long distance runners who were either physically active (HAY) or inactive (LAY) in young age. Twelve men in HAY group and eight men in LAY group participated. Structural, functional, and biochemical properties of Achilles tendon were estimated from magnetic resonance imaging, ultrasound video recordings, mechanical tests, and tendon biopsies, respectively. There was no difference between the groups with respect to tendon cross-sectional area or tendon free length. There was no difference between the groups with respect to maximal force or mechanical properties. The collagen content, enzymatic and nonenzymatic cross-link density did not differ between the groups, nor did collagen fibril density, diameter, and area. There was a correlation between age and pentosidine/collagen within the groups [(HAY: P < 0.05 and r(2) = 0.47) and (LAY: P < 0.05 and r(2) = 0.52)]. The data suggest that high or low activity during youth did not appreciably influence the mechanical, structural, or biochemical properties of the Achilles tendon in adult long distance runners.

  11. Application of lariat lock catch knot suture in the achilles tendon rupture

    PubMed Central

    Wang, Baocang; Feng, Xiaona; Yan, Ming; Wang, Hui; Li, Yong

    2015-01-01

    The aim of this study was to summarize the clinical experience of repairing the Achilles tendon rupture by lariat lock catch knot suture. Between January 2011 and February, 2014, 32 cases of the Achilles tendon rupture were treated by lariat lock catch knot suture. There were 26 males and 6 females, with the average age of 39 years (range 17-53 years), including 13 left knees and 19 right knees. 29 wounds healed by first intention, and 3 cases who were performed local flap transfer due to necrosis of skin were healed by second intention. Thirty-two cases were followed up 10-25 months (13 months on average). No re-rupture of Achilles tendon or deep infection occurred during follow-up period. According to Arner-Lindholm assessment standard, the results were excellent in 19 cases and good in 13 cases, the excellent and good rate was 100%. Lariat lock catch knot suture is a safe and effective method for repairing Achilles tendon. PMID:26770612

  12. [Successive ruptures of patellar and Achilles tendons. Anabolic steroids in competitive sports].

    PubMed

    Isenberg, J; Prokop, A; Skouras, E

    2008-01-01

    Derivatives of testosterone or of 19-nor-testosterone are used as anabolics for the purpose of improving performance although the effect of anabolics is known still to be under discussion. The use of anabolic steroids continues among competitive athletes despite increased controls and increasingly frequent dramatic incidents connected with them. Whereas metabolic dysfunction during anabolic use is well documented, ruptures of the large tendons are rarely reported. Within 18 months, a 29-year-old professional footballer needed surgery for rupture of the patellar tendon and of both Achilles tendons. Carefully directed questioning elicited confirmation that he had taken different anabolic steroids regularly for 3 years with the intention of improving his strength. After each operation anabolic steroids were taken again at a high dosage during early convalescence and training. Minimally invasive surgery and open suturing techniques led to complete union of the Achilles tendons in good time. Training and anabolic use (metenolon 300 mg per week) started early after suturing of the patellar tendon including bone tunnels culminated in histologically confirmed rerupture after 8 weeks. After a ligament reconstruction with a semitendinosus tendon graft with subsequent infection, the tendon and reserve traction apparatus were lost. Repeated warnings of impaired healing if anabolic use was continued had been given without success. In view of the high number of unrecorded cases in competitive and athletic sports, we can assume that the use of anabolic steroids is also of quantitative relevance in the operative treatment of tendon ruptures.

  13. Effect of muscle contraction levels on the force-length relationship of the human Achilles tendon during lengthening of the triceps surae muscle-tendon unit.

    PubMed

    Sugisaki, Norihide; Kawakami, Yasuo; Kanehisa, Hiroaki; Fukunaga, Tetsuo

    2011-07-28

    Findings from animal experiments are sometimes contradictory to the idea that the tendon structure is a simple elastic spring in series with muscle fibers, and suggest influence of muscle contraction on the tendon mechanical properties. The purpose of the present study was to investigate the influence of muscle contraction levels on the force-length relationship of the human Achilles tendon during lengthening of the triceps surae muscle-tendon unit. For seven subjects, ankle dorsiflexion was performed without (passive condition) and with contraction of plantar flexor muscles (eccentric conditions, at 3 contraction levels) on an isokinetic dynamometer. Deformation of the Achilles tendon during each trial was measured using ultrasonography. The Achilles tendon force corresponding to the tendon elongation of 10mm in the passive condition was significantly smaller than those in the eccentric conditions (p<0.05 or p<0.01). Within the eccentric conditions, the Achilles tendon force corresponding to the tendon elongation of 10mm was significantly greater in the maximal contraction level than those in submaximal eccentric conditions (p<0.05 or p<0.01). In addition, the tendon stiffness was greater in higher contraction levels (p<0.05 or p<0.01). Present results suggest that the human tendon structure is not a simple elastic spring in series with muscle fibers.

  14. Overweight and obesity alters the cumulative transverse strain in the Achilles tendon immediately following exercise.

    PubMed

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

    2013-07-01

    This research evaluated the effect of obesity on the acute cumulative transverse strain of the Achilles tendon in response to exercise. Twenty healthy adult males were categorized into 'low normal-weight' (BMI <23 kg m(-2)) and 'overweight' (BMI >27.5 kg m(-2)) groups based on intermediate cut-off points recommended by the World Health Organization. Longitudinal sonograms of the right Achilles tendon were acquired immediately prior and following weight-bearing ankle exercises. Achilles tendon thickness was measured 20-mm proximal to the calcaneal insertion and transverse tendon strain was calculated as the natural log of the ratio of post- to pre-exercise tendon thickness. The Achilles tendon was thicker in the overweight group both prior to (t18 = -2.91, P = 0.009) and following (t18 = -4.87, P < 0.001) exercise. The acute transverse strain response of the Achilles tendon in the overweight group (-10.7 ± 2.5%), however, was almost half that of the 'low normal-weight' (-19.5 ± 7.4%) group (t18 = -3.56, P = 0.004). These findings suggest that obesity is associated with structural changes in tendon that impairs intra-tendinous fluid movement in response to load and provides new insights into the link between tendon pathology and overweight and obesity.

  15. Reconstruction of compound loss of lateral malleolus and lateral ankle ligaments with double-bundle Achilles tendon-bone allograft.

    PubMed

    Ko, Dukhwan; Jung, Hong-Geun; Kim, Hyeung-June; Cha, Seung-Han; Nam, Kyoung-Mo

    2014-01-01

    Open ankle fracture, including compound loss of the lateral malleolus, lateral ankle ligaments, and overlying skin, is a severe injury and can result in ankle instability and permanent disability. Treatment of this injury is challenging and requires bone grafting and soft tissue reconstruction. In the present report, we describe a unique reconstruction technique for compound loss of the lateral malleolus, lateral ankle ligaments, and the overlying skin using a double-bundle Achilles tendon-bone allograft combined with a reverse sural fasciocutaneous flap. The patient obtained a stable ankle with nearly full range of motion and displayed satisfactory function during the follow-up period.

  16. Experimental Diabetes Alters the Morphology and Nano-Structure of the Achilles Tendon

    PubMed Central

    de Oliveira, Rodrigo Ribeiro; Medina de Mattos, Rômulo; Magalhães Rebelo, Luciana; Guimarães Meireles Ferreira, Fernanda; Tovar-Moll, Fernanda; Eurico Nasciutti, Luiz; de Castro Brito, Gerly Anne

    2017-01-01

    Although of several studies that associate chronic hyperglycemia with tendinopathy, the connection between morphometric changes as witnessed by magnetic resonance (MR) images, nanostructural changes, and inflammatory markers have not yet been fully established. Therefore, the present study has as a hypothesis that the Achilles tendons of rats with diabetes mellitus (DM) exhibit structural changes. The animals were randomly divided into two experimental groups: Control Group (n = 06) injected with a vehicle (sodium citrate buffer solution) and Diabetic Group (n = 06) consisting of rats submitted to intraperitoneal administration of streptozotocin. MR was performed 24 days after the induction of diabetes and images were used for morphometry using ImageJ software. Morphology of the collagen fibers within tendons was examined using Atomic Force microscopy (AFM). An increase in the dimension of the coronal plane area was observed in the diabetic group (8.583 ± 0.646 mm2/100g) when compared to the control group (4.823 ± 0.267 mm2/100g) resulting in a significant difference (p = 0.003) upon evaluating the Achilles tendons. Similarly, our analysis found an increase in the size of the transverse section area in the diabetic group (1.328 ± 0.103 mm2/100g) in comparison to the control group (0.940 ± 0.01 mm2/100g) p = 0.021. The tendons of the diabetic group showed great irregularity in fiber bundles, including modified grain direction and jagged junctions and deformities in the form of collagen fibrils bulges. Despite the morphological changes observed in the Achilles tendon of diabetic animals, IL1 and TNF-α did not change. Our results suggest that DM promotes changes to the Achilles tendon with important structural modifications as seen by MR and AFM, excluding major inflammatory changes. PMID:28095484

  17. Achilles Pain.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Five ailments which can cause pain in the achilles tendon area are: (1) muscular strain, involving the stretching or tearing of muscle or tendon fibers; (2) a contusion, inflammation or infection called tenosynovitis; (3) tendonitis, the inflammation of the tendon; (4) calcaneal bursitis, the inflammation of the bursa between the achilles tendon…

  18. Acute tear of the fascia cruris at the attachment to the Achilles tendon: a new diagnosis

    PubMed Central

    Webborn, Nick; Morrissey, Dylan; Sarvananthan, Kasthuri; Chan, Otto

    2015-01-01

    Background The fascia cruris encloses the posterior structures of the calf and connects to the paratenon and the Achilles tendon. We describe the clinical presentation, ultrasound imaging characteristics and the time to the recovery of tears of the fascia cruris at the attachment to the Achilles tendon. Methods Retrospective review of 11 tears of the fascia cruris in the different legs as separate events in 9 patients (6 male and 3 female, mean age 35.52 years, range 11–48) identified using diagnostic ultrasound, after presenting with Achillodynia. Results 11 participants presented at a mean of 4.5 weeks (range 0.5–12) after onset of symptoms. The left Achilles was more commonly injured than the right (7 : 4) and the lateral side more than the medial (6 : 4) with one case with medial and lateral presentation. Clinically, there was swelling and tenderness over the medial or lateral border in the mid to upper portion of the Achilles. 7 of the 11 (63.6%) had functional overpronation. Ultrasound appearances of a tear were identified as hypoechoic area extending from the medial or lateral border of the Achilles extending along the anatomical plane of the fascia cruris. Average return to activity was 5.2 weeks (range 1–22). Participants presenting later had longer recovery but all participants returned to full activity (r=0.4). Conclusions This is the first description of the clinical details and sonographic findings of a tear to the fascia cruris at its attachment to the Achilles tendon. This needs to be considered as a cause of Achillodynia in athletes as recognition will affect the management. PMID:25202137

  19. Surgical Correction of the Achilles Tendon for Diabetic Foot Ulcerations and Charcot Neuroarthropathy.

    PubMed

    Ramanujam, Crystal L; Zgonis, Thomas

    2017-04-01

    Achilles tendon pathologic conditions are implicated in contributing to the development of many diabetic foot complications including diabetic foot ulceration and Charcot neuroarthropathy. Surgical correction of the diabetic equinus deformity has been studied as an isolated or adjunctive treatment when dealing with difficult-to-close diabetic foot ulcerations or when surgically addressing the diabetic Charcot neuroarthropathy foot or ankle. This article reviews the most common indications, complications, and surgical procedures for equinus correction by either a tendo-Achilles lengthening or gastrocnemius recession for the management of diabetic foot conditions.

  20. High voltage pulsed current in collagen realignment, synthesis, and angiogenesis after Achilles tendon partial rupture

    PubMed Central

    Rampazo, Érika P.; Liebano, Richard E.; Pinfildi, Carlos Eduardo; Folha, Roberta A. C.; Ferreira, Lydia M.

    2016-01-01

    ABSTRACT Objective To verify the efficacy of high voltage pulsed current in collagen realignment and synthesis and in angiogenesis after the partial rupturing of the Achilles tendon in rats. Method Forty male Wistar rats were randomized into four groups of 10 animals each: sham, cathodic stimulation, anodic stimulation, and alternating stimulation. Their Achilles tendons were submitted to direct trauma by a free-falling metal bar. Then, the treatment was administered for six consecutive days after the injury. In the simulation group, the electrodes were positioned on the animal, but the device remained off for 30 minutes. The other groups used a frequency of 120 pps, sensory threshold, and the corresponding polarity. On the seventh day, the tendons were removed and sent for histological slide preparation for birefringence and Picrosirius Red analysis and for blood vessel quantification. Results No significant difference was observed among the groups regarding collagen realignment (types I or III collagen) or quantity of blood vessels. Conclusion High voltage pulsed current for six consecutive days was not effective in collagen realignment, synthesis, or angiogenesis after the partial rupturing of the Achilles tendon in rats. PMID:27556387

  1. Strenuous Treadmill Running Induces a Chondrocyte Phenotype in Rat Achilles Tendons

    PubMed Central

    Xu, Shao-Yong; Li, Shu-Fen; Ni, Guo-Xin

    2016-01-01

    Background Although tendinopathy is common, its underlying pathogenesis is poorly understood. This study aimed to investigate the possible pathogenesis of tendinopathy. Material/Methods In this study, a total of 24 rats were randomly and evenly divided into a control (CON) group and a strenuous treadmill running (STR) group. Animals in the STR group were subjected to a 12-week treadmill running protocol. Subsequently, all Achilles tendons were harvested to perform histological observation or biochemical analyses. Results Histologically, hypercellularity and round cells, as well as disorganized collagen fibrils, were presented in rat Achilles tendon sections from the STR group. Furthermore, our results showed that the expression of aggrecan, collagen type II (Col II), and Sex-Determining Region Y Box 9 (Sox 9) were markedly increased in the STR group compared with that in the CON group. Additionally, the mRNA expression of bone morphogenetic protein-2 (BMP-2) and biglycan was significantly up-regulated in the STR group in contrast to that in CON group. Conclusions These results suggest that a 12-week strenuous treadmill running regimen can induce chondrocyte phenotype in rat Achilles tendons through chondrogenic differentiation of tendon stem cells (TSCs) by BMP-2 signaling. PMID:27742920

  2. Achilles tendon rupture: a review of etiology, population, anatomy, risk factors, and injury prevention.

    PubMed

    Hess, Gregory William

    2010-02-01

    Sports participation has undergone an increase in recent decades. Injury due to sporting activity has also recently risen. The Achilles tendon has been one of the most common sports-related injuries. A 2 in 100,000 individual Achilles tendon injury rate increased to a 12 in 100,000 individual injury rate in less than 10 years. The injury is typically observed in men in the fourth to fifth decades of life. Male to female injury ratios range from 2:1 to 12:1. Running, jumping, and agility activities involving eccentric loading and explosive plyometric contractions are usual mechanisms. Natural aging allows predisposing chronic degeneration of the tendon. Blood flow decreases and stiffness increases with aging to decrease the ability to withstand stress. Noninflammatory tendinosis and chronic tendinopathy are 2 separate processes proposed for tendon degeneration and subsequent rupture. Rupture typically occurs 2 to 6 cm proximal to the calcaneal insertion. Predisposing factors are grouped into 2 categories: intrinsic and extrinsic risk factors. Avoidance of degenerative changes within the tendon is the primary method to prevent rupture. Regular physical activity as athletes age also promotes tendon hypertrophy, increases nutrient delivery, and reduces collagen fiber fatigue.

  3. The seasonal variation of Achilles tendon ruptures in Vancouver, Canada: a retrospective study

    PubMed Central

    Scott, Alex; Grewal, Navdeep; Guy, Pierre

    2014-01-01

    Objective To examine the seasonal distribution of tendon ruptures in a large cohort of patients from Vancouver, Canada. Design Retrospective chart review. Setting Acute Achilles tendon rupture cases that occurred from 1987 to 2010 at an academic hospital in Vancouver, Canada. Information was extracted from an orthopaedic database. Participants No direct contact was made with the participants. The following information was extracted from the OrthoTrauma database: age, sex, date of injury and season (winter, spring, summer and autumn), date of surgery if date of injury was unknown and type of injury (sport related or non-sport related/unspecified). Only acute Achilles tendon rupture cases were included; chronic cases were excluded along with those that were conservatively managed. Primary and secondary outcomes The primary outcome was to determine the seasonal pattern of Achilles tendon rupture. Secondary outcomes, such as differences in gender and mechanism of sport (non-sport vs sport related), were also assessed. Results There were 543 cases in total; 83% of the cases were men (average age 39.3) and 17% were women (average age 37.3). In total, 76% of cases were specified as sport related. The distribution of injuries varied significantly across seasons (χ2, p<0.05), with significantly more cases occurring in spring. The increase in the number of cases in spring was due to sport-related injuries, whereas non-sport-related cases were distributed evenly throughout the year. Conclusions The seasonality of sport-related Achilles tendon ruptures should be considered when developing preventive strategies and when timing their delivery. PMID:24519875

  4. [Symptoms in area of the Achilles tendon. Etiology and therapeutic considerations].

    PubMed

    Biedert, R

    1991-10-01

    A number of pathologic conditions can produce posterior heel pain, making it difficult to distinguish the exact cause. Only a careful physical examination allows the probable diagnosis, which is the first and most important step in a successful therapy. Pathologically, the Achilles tendon itself may be inflamed secondary to degeneration owing to a decreased blood supply or the result of a partial rupture. The inflammation can also be accompanied by microtears or calcium deposits. In most cases the tendon sheath and the mesotenon are also involved (tenosynovitis). The retrocalcaneal bursa located between the posterior angle of the os calcis and the Achilles tendon may become inflamed and hypertrophic. It is frequently associated with a prominent superior tuberosity of the os calcis. In a few cases there was also an irritation of the bursa between the Achilles tendon and the skin caused by ill-fitting shoes. Over a 3-year period, 102 patients who engaged in different sports were treated for problems in the Achilles tendon area and retrospectively reviewed with a follow up of 18.8 months. Most of them were runners (48%), followed by soccer players (15.7%) and tennis players (5.9%). The mean age was 36 years. In the vast majority of patients (n = 70, 68.6%) nonoperative treatment was successful. In this group there were 45 cases (65%) with postural abnormalities and excessive pronation requiring correction by means of orthotic appliances. In 19 patients (27%) the problems were caused by a muscular imbalance, and in 15 cases (21%) wrong training methods with overuse had caused the inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Influence of running shoes and cross-trainers on Achilles tendon forces during running compared with military boots.

    PubMed

    Sinclair, Jonathan; Taylor, P J; Atkins, S

    2015-06-01

    Military recruits are known to be susceptible to Achilles tendon pathology. The British Army have introduced footwear models, the PT-03 (cross-trainer) and PT1000 (running shoes), in an attempt to reduce the incidence of injuries. The aim of the current investigation was to examine the Achilles tendon forces of the cross-trainer and running shoe in relation to conventional army boots. Ten male participants ran at 4.0 m/s in each footwear condition. Achilles tendon forces were obtained throughout the stance phase of running and compared using repeated-measures ANOVAs. The results showed that the time to peak Achilles tendon force was significantly shorter when running in conventional army boots (0.12 s) in comparison with the cross-trainer (0.13 s) and running shoe (0.13 s). Achilles tendon loading rate was shown to be significantly greater in conventional army boots (38.73 BW/s) in comparison with the cross-trainer (35.14 BW/s) and running shoe (33.57 BW/s). The results of this study suggest that the running shoes and cross-trainer footwear are associated with reductions in Achilles tendon parameters that have been linked to the aetiology of injury, and thus it can be hypothesised that these footwear could be beneficial for military recruits undertaking running exercises.

  6. The AutoQual ultrasound elastography method for quantitative assessment of lateral strain in post-rupture Achilles tendons.

    PubMed

    Brown, Phillip G; Alsousou, Joseph; Cooper, Ashley; Thompson, Mark S; Noble, J Alison

    2013-10-18

    This paper presents the AutoQual elastography method: a novel algorithm that improves the quality of 2D displacement field calculation from ultrasound radio frequency (RF) sequences of acutely ruptured Achilles tendons to determine image-lateral strain fields and has potential use for ligaments and muscles. This method uses 2D bicubic spline interpolation of the RF signal, Quality Determined Search, Automatic Search Range and Adaptive Block Size components as a novel combination that is designed to improve continuity and decrease displacement field noise, especially in areas of low signal strength. We present a simple experiment for quantitatively comparing the AutoQual method to a multiscale (MS) elastography method from ultrasound RF sequences of a 5% agar phantom for rigid body motion and known lateral strain loads with speeds up to 5mm/s. We finally present examples of four in vivo Achilles tendons in various damage states and with manual or artificially controlled passive flexion of the foot. Results show that the AutoQual method offers a substantial improvement on the MS method, achieving similar performance for rigid body tracking at all speeds, a lower normalized square error at all strains induced and a more continuous strain field at higher compression rates. AutoQual also showed a greater average normalized cross correlation for image blocks in the area of interest, a lower standard deviation of the strain field and a visually more acceptable point tracking for in vivo examples. This work demonstrates lateral ultrasound elastography which is robust to the complex passive motion of the Achilles and to various imaging artifacts associated with imaging tendon rupture. This method potentially has a wide clinical application for assessing in vivo strains in and hence mechanical function of any near skin surface tissues that are longitudinally loaded.

  7. Effects of tendon viscoelasticity in Achilles tendinosis on explosive performance and clinical severity in athletes.

    PubMed

    Wang, H-K; Lin, K-H; Su, S-C; Shih, T T-F; Huang, Y-C

    2012-12-01

    The aim was to compare viscoelastic properties of Achilles tendons between legs in elite athletes with unilateral tendinosis, and to investigate relationships between the properties and explosive performance and clinical severity. Seventeen male athletes (mean ± standard deviation age, 27.3 ± 2.0 years) who had unilateral, chronic middle-portion tendinopathy of the Achilles tendon were assessed by the Victorian Institute of Sport Assessment questionnaire, measurements of tendon viscoelastic properties, voluntary electromechanical delay (EMD), normalized rate of force development (RFD), and one-leg hopping distance. Compared with the non-injured leg, the tendinopathic leg showed reduced tendon stiffness (-19.2%. P < 0.001), greater mechanical hysteresis (+21.2%, P = 0.004), lower elastic energy storage and release (-14.2%, P = 0.002 and -19.1%, P < 0.001), lower normalized RFD at one-fourth (-16.3%, P = 0.02), 2/4 (-17.3%, P = 0.006), and three-fourths maximal voluntary contraction (-13.7%, P = 0.02), longer soleus and medial gastrocnemius voluntary EMD (+26.9%, P = 0.009 and +24.0%, P = 0.004), and shorter hopping distances (-34.1%, P < 0.001). Tendon stiffness was correlated with normalized RFD, voluntary EMD in the medial gastrocnemius, and hopping distances (r ranged from -0.35 to 0.64, P < 0.05). Hysteresis was correlated to the soleus voluntary EMD and hopping distances (r = 0.42 and -0.39, P < 0.05). We concluded that altered tendon viscoelastic properties in Achilles tendinosis affect explosive performance in athletes.

  8. Limited open repair of ruptured Achilles tendons with Bunnel-type sutures.

    PubMed

    Park, H G; Moon, D H; Yoon, J M

    2001-12-01

    A new method of repairing Achilles tendons, which uses a small medial skin incision with a Bunnel-type suture, was performed on 14 patients, and the clinical results were found satisfying. In order to restore the Achilles tendon to its original length, restore tensile strength in the suture site, and minimize injury to the sural nerve, an operative procedure has been devised which uses a limited open repair with a Bunnel-type suture. We followed 14 patients who had undergone the new procedure for a mean interval of 26 months after the injury. They returned to work in six weeks and to playing sports in 25 weeks. There were no cases of late rerupture nor injuries to the sural nerve. This technique approximated the preinjury length and resting tension of the musculo-tendinous apparatus and minimized sural nerve injury.

  9. Neglected Achilles Tendon Rupture Treated with Flexor Hallucis Longus transfer with two turndown gastrocnemius fascia flap and reinforced with plantaris tendon.

    PubMed

    Mao, Haijiao; Shi, Zengyuan; Xu, Dachuan; Liu, Zhenxin

    2015-09-01

    Neglected Achilles Tendon Ruptures are commonly seen by orthopaedic surgeons. In cases resistant to conservative treatment, a variety of surgical procedures have been utilized in the past. The senior -surgeon at our institution has utilized a technique -employing two turndown fascia flaps fashioned from the proximal Achilles tendon augmented by a tenomyodesis of the flexor hallucis longus and plantaris tendon. The purpose of this study was to assess the clinical outcome of all patients who underwent this procedure. The medical records of 10 cases that underwent this procedure were retrospectively reviewed. We completed data collection sets using the American Orthopaedic Foot and Ankle Society ankle-hind foot scores, isokinetic evaluation, and postoperative magnetic resonance imaging (MRI) at 1 year of follow-up. The mean American Orthopaedic Foot and Ankle Society ankle-hind foot scores improved from 64.4±3.54. Isokinetic testing at 30º/sec and 120º/sec revealed an mean deficits of 24.5%, respectively, in the plantar flexion peak torque of the involved ankle than non-involved ankle. The flexor hallucis longus tendon, gastrocnemius fascia flap and plantaris were well -integrated into the Achilles tendon forming a homogenous tendon, which was confirmed in MRI. Our subjective and objective data indicate that the reconstructive technique using flexor hallucis longus transfer with two turndown gastrocnemius fascia flaps and plantaris tendon is a good option for repairing large gap defect of Achilles tendon.

  10. Z-lengthening of the Achilles Tendon with Transverse Skin Incision

    PubMed Central

    Oh, Jong Seok; Lee, Jong Seo; Lee, Tae Hoon

    2014-01-01

    Background The risk of various complications after Achilles tendon lengthening is mainly related to the length of surgical exposure and the lengthening method. A comprehensive technique to minimize the complications is required. Methods The treatment of Achilles tendon tightness in 57 patients (95 ankles) were performed by using a short transverse incision on a skin crease of the heel and by Z-lengthening of the tendon. In the severe cases, two or three transverse incisions were required for greater lengthening of the tendon, and a serial cast or Ilizarov apparatus was applied for the gradual correction. The results of these 95 ankles were compared to those of 18 ankles, which underwent percutaneous sliding lengthening, and to the 19 ankles, which received Z-lengthening with a medial longitudinal incision. Results The functional and cosmetic satisfaction was achieved among those who underwent the tendon lengthening with the new technique. The mean American Orthopaedic Foot & Ankle Society (AOFAS) score improved from 56.1 to 81.8. The second operations to correct recurrence were performed in the two cerebral palsy patients. Conclusions The new technique has a low rate of complications such as scarring, adhesion, total transection, excessive lengthening, and recurrence of shortening. The excellent cosmesis and the short operation time are the additional advantages. PMID:24900904

  11. Calcific spurs at the insertion of the Achilles tendon: a clinical and histological study

    PubMed Central

    Johansson, Kristian Jarl Johan; Sarimo, Janne Julius; Lempainen, Lasse Lennart; Laitala-Leinonen, Tiina; Orava, Sakari Yrjö

    2012-01-01

    Summary In active people, insertional calcific tendinopathy (CT) of the Achilles tendon is rare. We evaluated the results of surgical treatment for Achilles tendon CT and analyzed post-surgery Achilles tendon histological features. The study included 36 operations in 34 patients. Twenty-eight (78%) cases had a resection of a Haglund’s deformity performed. The mean age of the patients was 42 years (range=23 to 68). Thirteen of the patients were professional athletes and 20 recreational athletes. In twenty-five (69%) cases, the result of surgery was rated good, in nine cases (25%) moderate and in two (6%) cases poor. The mean age of those with a good result was 10 years lower (40 versus 50 years) than those with a moderate result (p=0.0239). Higher athletic activity was also related to a better outcome (p=0.0205). Histology samples showed fast remodellation and stem-cell activation. Surgery seemed to result in a good outcome in patients with or without a Haglund’s deformity which failed conservative treatment. PMID:23738309

  12. Application of Computed Tomography Processed by Picture Archiving and Communication Systems in the Diagnosis of Acute Achilles Tendon Rupture

    PubMed Central

    Tian, Jing; Xie, Bing; Zhang, Hao

    2016-01-01

    The applications of CT examination in the diagnosis of the acute Achilles tendon rupture (AATR) were investigated. A total of 36 patients with suspected acute Achilles tendon rupture were tested using physical examination, ultrasound, and 3DCT scanning, respectively. Then, surgery was performed for the patients who showed positive result in at least two of the three tests for AATR. 3DVR, MPR, and the other CT scan image processing and diagnosis were conducted in PACS (picture archiving and communication system). PACS was also used to measure the length of distal broken ends of the Achilles tendon (AT) to tendon calcaneal insertion. Our study indicated that CT has the highest accuracy in diagnosis of acute Achilles tendon complete rupture. The length measurement is matched between PACS and those actually measured in operation. CT not only demonstrates more details directly in three dimensions especially with the rupture involved calcaneal insertion flap but also locates the rupture region for percutaneous suture by measuring the length of distal stump in PACS without the effect of the position of ankle. The accuracy of CT diagnosis for Achilles tendon partial rupture is yet to be studied. PMID:28078295

  13. Application of Computed Tomography Processed by Picture Archiving and Communication Systems in the Diagnosis of Acute Achilles Tendon Rupture.

    PubMed

    Xue, Hai-Peng; Liu, Xin-Wei; Tian, Jing; Xie, Bing; Yang, Chao; Zhang, Hao; Zhou, Da-Peng

    2016-01-01

    The applications of CT examination in the diagnosis of the acute Achilles tendon rupture (AATR) were investigated. A total of 36 patients with suspected acute Achilles tendon rupture were tested using physical examination, ultrasound, and 3DCT scanning, respectively. Then, surgery was performed for the patients who showed positive result in at least two of the three tests for AATR. 3DVR, MPR, and the other CT scan image processing and diagnosis were conducted in PACS (picture archiving and communication system). PACS was also used to measure the length of distal broken ends of the Achilles tendon (AT) to tendon calcaneal insertion. Our study indicated that CT has the highest accuracy in diagnosis of acute Achilles tendon complete rupture. The length measurement is matched between PACS and those actually measured in operation. CT not only demonstrates more details directly in three dimensions especially with the rupture involved calcaneal insertion flap but also locates the rupture region for percutaneous suture by measuring the length of distal stump in PACS without the effect of the position of ankle. The accuracy of CT diagnosis for Achilles tendon partial rupture is yet to be studied.

  14. Can transcutaneous electrical nerve stimulation improve achilles tendon healing in rats?

    PubMed Central

    Folha, Roberta A. C.; Pinfildi, Carlos E.; Liebano, Richard E.; Rampazo, Érika P.; Pereira, Raphael N.; Ferreira, Lydia M.

    2015-01-01

    BACKGROUND: Tendon injury is one of the most frequent injuries in sports activities. TENS is a physical agent used in the treatment of pain but its influence on the tendon's healing process is unclear. OBJECTIVE: To evaluate the influence of TENS on the healing of partial rupture of the Achilles tendon in rats. METHOD: Sixty Wistar rats were submitted to a partial rupture of the Achilles tendon by direct trauma and randomized into six groups (TENS or Sham stimulation) and the time of evaluation (7, 14, and 21 days post-injury). Burst TENS was applied for 30 minutes, 6 days, 100 Hz frequency, 2 Hz burst frequency, 200 µs pulse duration, and 300 ms pulse train duration. Microscopic analyses were performed to quantify the blood vessels and mast cells, birefringence to quantify collagen fiber alignment, and immunohistochemistry to quantify types I and III collagen fibers. RESULTS: A significant interaction was observed for collagen type I (p=0.020) where the TENS group presented lower percentage in 14 days after the lesion (p=0.33). The main group effect showed that the TENS group presented worse collagen fiber alignment (p=0.001) and lower percentage of collagen III (p=0.001) and the main time effect (p=0.001) showed decreased percentage of collagen III at 7 days (p=0.001) and 14 days (p=0.001) after lesion when compared to 21 days. CONCLUSIONS: Burst TENS inhibited collagen I and III production and impaired its alignment during healing of partial rupture of the Achilles tendon in rats. PMID:26647744

  15. Flexor Hallucis Longus Tendon Transfer for Calcific Insertional Achilles Tendinopathy.

    PubMed

    Howell, Michael A; Catanzariti, Alan R

    2016-01-01

    Calcific insertional Achilles tendinopathy can result in significant pain and disability. Although some patients respond to nonoperative therapy, many patients are at risk for long-term morbidity and unpredictable clinical outcomes. There is no evidence-based data to support the timing of operative invention, choice of procedures, or whether equinus requires treatment. This article suggests the need for a classification system based on physical examination and imaging to help guide treatment. There is an obvious need for evidence-based studies evaluating outcomes and for properly conducted scientific research to establish appropriate treatment protocols.

  16. Effect of Basic Fibroblast Growth Factor on Achilles Tendon Healing in Rabbit

    PubMed Central

    Najafbeygi, Arash; Fatemi, Mohammad Javad; Lebaschi, Amir Hussein; Mousavi, Seyed Jaber; Husseini, Seyed Abouzar; Niazi, Mitra

    2017-01-01

    BACKGROUND Tendon injuries are common and it takes a long time for an injured tendon to heal. Adverse phenomena such as adhesion and rupture are associated with these injuries. Finding a method to reduce the time required for healing which improves the final outcome, will lead to decreased frequency and intensity of adverse consequences. This study was designed to investigate the effects of basic fibroblast growth factor on the healing of the Achilles tendon in rabbits METHODS In 10 New Zealand white rabbits, Achilles tendon was cut at the intersection of the distal and middle thirds on both hind legs. One microgram of recombinant basic fibroblast growth factor (bFGF) was injected in the proximal and distal stumps of the cut tendon on the right side (study group). Normal saline of equal volume was injected on the left side in the same way (control group). Then the tendons were repaired with 5/0 nylon using modified Kessler technique. A cast was made to immobilize each leg. On day 42, rabbits were euthanized and both hind legs were amputated. Tensometry and histopathologic examination were done on specimens. RESULTS In tensometric studies, more force was required to rupture the repair site in study group. In histopathologic examination, collagen fibers had significantly better orientation and organization in the study group. No difference was noted regarding number of fibroblast and fibrocytes, and degree of angiogenesis in the two groups. CONCLUSION Application of basic fibroblast growth factor at tendon repair site improves the healing process through improvement of collagen fiber orientation and increase in biomechanical resistance. PMID:28289610

  17. Genome-wide association screens for Achilles tendon and ACL tears and tendinopathy

    PubMed Central

    Roos, Thomas R.; Roos, Andrew K.; Kleimeyer, John P.; Ahmed, Marwa A.; Goodlin, Gabrielle T.; Fredericson, Michael; Ioannidis, John P. A.; Avins, Andrew L.; Dragoo, Jason L.

    2017-01-01

    Achilles tendinopathy or rupture and anterior cruciate ligament (ACL) rupture are substantial injuries affecting athletes, associated with delayed recovery or inability to return to competition. To identify genetic markers that might be used to predict risk for these injuries, we performed genome-wide association screens for these injuries using data from the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort consisting of 102,979 individuals. We did not find any single nucleotide polymorphisms (SNPs) associated with either of these injuries with a p-value that was genome-wide significant (p<5x10-8). We found, however, four and three polymorphisms with p-values that were borderline significant (p<10−6) for Achilles tendon injury and ACL rupture, respectively. We then tested SNPs previously reported to be associated with either Achilles tendon injury or ACL rupture. None showed an association in our cohort with a false discovery rate of less than 5%. We obtained, however, moderate to weak evidence for replication in one case; specifically, rs4919510 in MIR608 had a p-value of 5.1x10-3 for association with Achilles tendon injury, corresponding to a 7% chance of false replication. Finally, we tested 2855 SNPs in 90 candidate genes for musculoskeletal injury, but did not find any that showed a significant association below a false discovery rate of 5%. We provide data containing summary statistics for the entire genome, which will be useful for future genetic studies on these injuries. PMID:28358823

  18. Amniotic Tissues for the Treatment of Chronic Plantar Fasciosis and Achilles Tendinosis

    PubMed Central

    Werber, Bruce

    2015-01-01

    Introduction. Allogeneic amniotic tissue and fluid may be used to treat chronic plantar fasciosis and Achilles tendinosis. This innovative approach involves delivering a unique allograft of live human cells in a nonimmunogenic structural tissue matrix to treat chronic tendon injury. These tissues convey very positive regenerative attributes; procurement is performed with maternal consent during elective caesarian birth. Materials and Methods. In the present investigation all patients were unresponsive to multiple standard therapies for a minimum of 6 months and were treated with one implantation of PalinGen SportFLOW around the plantar fascia and/or around the Achilles paratenon. The patients were given a standard protocol for postimplant active rehabilitation. Results. The analogue pretreatment pain score (VAS) of 8. By the fourth week after treatment, all patients had significantly reduced self-reported pain. Twelve weeks following the procedure the average pain level had reduced to only 2. No adverse reactions were reported in any of the patients. Conclusion. All patients in this study experienced heel or Achilles pain, unresponsive to standard therapy protocols. After treatment all patients noted significant pain reduction, indicating that granulized amniotic membrane and amniotic fluid can be successfully used to treat both chronic plantar fasciosis and Achilles tendinosis. PMID:26491722

  19. Low recurrence rate after mini surgery outside the tendon combined with short rehabilitation in patients with midportion Achilles tendinopathy

    PubMed Central

    Alfredson, Håkan

    2016-01-01

    Background There is a general opinion that a structured and specific rehabilitation is needed after treatment of midportion Achilles tendinopathy to minimize recurrence of the condition. There is sparse knowledge about the recurrence rates in large patient materials after specific treatments for midportion Achilles tendinopathy. Aim This study aimed to investigate the recurrence rates in a large number of patients with chronic painful midportion Achilles tendinopathy that had been surgically treated with the ultrasound (US) and Doppler (DP)-guided mini-surgical scraping technique. Postoperatively, a relatively simple rehabilitation protocol, including a range of movement exercises and gradually increased walking and biking before allowing free activity, was used. Materials and methods From a database, information about the recurrence rates after US + DP-guided mini-surgical scraping, performed by a single surgeon on 519 tendons with US + DP-verified chronic painful midportion Achilles tendinopathy, was obtained. Results Recurrence of painful midportion Achilles tendinopathy was found in 26 of 519 (5%) operated tendons, 13 from women and 13 from men. In 13 tendons, a close by located plantaris tendon was extirpated during the reoperation. Conclusion In this large material on patients treated with US + DP-guided mini-surgical scraping for midportion Achilles tendinopathy, there were few recurrences, although only a simple and nonspecific rehabilitation protocol was used. PMID:27274323

  20. Achilles Tendinosis Stopping the Progression to Disability.

    PubMed

    Chessin, Meta

    2012-09-01

    The purpose of this article is to differentiate between acute Achilles tendinitis and chronic Achilles tendinosis and to highlight a specific treatment protocol for mid-portion Achilles tendinosis. Tendinosis (degeneration of the tendon) results from chronic tissue injury and has long-term implications for a dancer's career. An eccentric heavy-load exercise protocol has been used successfully to treat tendinosis in athletes. A modified eccentric exercise protocol is proposed as one component of an effective rehabilitation program for dancers. This protocol facilitates tissue remodeling to build strength, flexibility, and adaptability of the Achilles tendon tissue, so that dancers can continue to dance without further complications of the injury.

  1. Different distributions of operative diagnoses for Achilles tendon overuse injuries in Italian and Finnish athletes

    PubMed Central

    Johansson, Kristian; Lempainen, Lasse; Sarimo, Janne; Laitala-Leinonen, Tiina; Orava, Sakari

    2016-01-01

    Summary Background the origin of chronic Achilles tendinopathy (AT) is currently unclear and epidemiological factors, such as ethnicity, may be associated. Methods intraoperative findings from the treatment of 865 Finnish and 156 Italian athletic patients with chronic Achilles tendon related pain were evaluated, retrospectively. The mean age was 34 years (range, 18 to 65 years) in the Finnish and 29 years (range, 17–63 years) in the Italian patients. In total, 786 patients were males and 226 females of which 84 and 87% Finnish, respectively. Data were collected, retrospectively from patient records. The differences in the frequencies of operative findings were assessed for statistical significance. Results retrocalcaneal bursitis, partial tear and chronic paratenonitis were the most prevalent findings in patients with chronic AT undergoing surgery. Tendinosis and chronic paratenonitis were significantly (p=0.011) more common in Finnish athletes. Italian patients exhibited significantly (p<0.001) more insertional calcific tendinopathy (heel spurs) and prominent posterosuperior calcaneal corners (Haglund’s heel). Conclusion ethnicity appears to be associated with specific characteristics of overuse-related Achilles tendon pathology. This is an issue that should be considered in the planning of genetic research on AT. PMID:27331038

  2. Macroscopic Anomalies and Pathological Findings in and Around the Achilles Tendon

    PubMed Central

    Johansson, Kristian; Lempainen, Lasse; Sarimo, Janne; Laitala-Leinonen, Tiina; Orava, Sakari

    2014-01-01

    Background: Nonsurgical treatments for chronic Achilles tendinopathy (AT) results in unpredictable success rates. Surgical treatment may be chosen as reports show mostly encouraging but variable success rates depending on the pathology. The distribution of surgically confirmed pathologies in AT is largely unknown. Purpose: To ascertain the distributions of macroscopically observed anomalies in participants undergoing surgical treatment for chronic AT. Study Design: Case series; Level of evidence, 4. Methods: The main macroscopic pathologies of 1661 chronic Achilles tendon overuse injuries, which were diagnosed and surgically treated by a single surgeon, were reviewed. The surgeries were performed on professional and recreational athletes during the years 1976-1980, 1986-1990, 1996-2000, and 2006-2010. Surgical diagnoses, along with age- and sport-specific characteristics, were collected retrospectively from patient records. Results: The relative proportion of tendinosis increased during the study period from 4.2% to 21%, and paratenonitis decreased from 50% to 26%. Retrocalcaneal pathologies were the most common surgically confirmed lesions at 30%, while the mean age at surgery increased by 11 years over the entire study period. Conclusion: Surgically confirmed pathologies in and around the Achilles tendon showed coherent changes, chronic paratenonitis, and retrocalcaneal problems as the most prevalent findings. The classification of midportion and insertional tendinopathy and retrocalcaneal bursitis in AT should strictly be used as a clinical diagnosis. During surgical evaluations, the diagnosis is further clarified as more specific pathologies may be identified. PMID:26535293

  3. Achilles tendon mechanical properties after both prolonged continuous running and prolonged intermittent shuttle running in cricket batting.

    PubMed

    Houghton, Laurence; Dawson, Brian; Rubenson, Jonas

    2013-08-01

    Effects of prolonged running on Achilles tendon properties were assessed after a 60 min treadmill run and 140 min intermittent shuttle running (simulated cricket batting innings). Before and after exercise, 11 participants performed ramp-up plantar flexions to maximum-voluntary-contraction before gradual relaxation. Muscle-tendon-junction displacement was measured with ultrasonography. Tendon force was estimated using dynamometry and a musculoskeletal model. Gradients of the ramp-up force-displacement curves fitted between 0-40% and 50-90% of the preexercise maximal force determined stiffness in the low- and high-force-range, respectively. Hysteresis was determined using the ramp-up and relaxation force-displacement curves and elastic energy storage from the area under the ramp-up curve. In simulated batting, correlations between tendon properties and shuttle times were also assessed. After both protocols, Achilles tendon force decreased (4% to 5%, P < .050), but there were no changes in stiffness, hysteresis, or elastic energy. In simulated batting, Achilles tendon force and stiffness were both correlated to mean turn and mean sprint times (r = -0.719 to -0.830, P < .050). Neither protocol resulted in fatigue-related changes in tendon properties, but higher tendon stiffness and plantar flexion force were related to faster turn and sprint times, possibly by improving force transmission and control of movement when decelerating and accelerating.

  4. Distal posterior tibial artery perforator flaps for the management of calcaneal and Achilles tendon injuries in diabetic and non-diabetic patients.

    PubMed

    Ignatiadis, Ioannis A; Georgakopoulos, Georgios D; Tsiampa, Vassiliki A; Polyzois, Vasilios D; Arapoglou, Dimitrios K; Papalois, Apostolos E

    2011-01-01

    Management of Achilles tendon and heel area defects is a common challenge for the reconstructive surgeon due to the lack of soft tissue availability in that region. In this article, we present our experience in covering these defects by using the distal perforator propeller flaps based on the posterior tibial artery. Perforator flaps are based on cutaneous, small diameter vessels that originate from a main pedicle and perforate the fascia or muscle to reach the skin. Their development has followed the understanding of the blood supply from a source artery to the skin. Six patients (five males and one female) underwent reconstruction by using the posterior tibial artery distal perforator flap for covering defects in the distal Achilles tendon region in patients with and without diabetes mellitus. Postoperative complications included a hypertrophic scar formation in one patient, partial marginal flap necrosis in another patient, and a wound infection in a third patient. All wounds were eventually healed by the last postoperative visit. In conclusion, perforator flaps based on the distal posterior tibial artery may be a reliable option for the coverage of small to moderate size defects of the Achilles tendon and heel area regions.

  5. Distal posterior tibial artery perforator flaps for the management of calcaneal and Achilles tendon injuries in diabetic and non-diabetic patients

    PubMed Central

    Ignatiadis, Ioannis A.; Georgakopoulos, Georgios D.; Tsiampa, Vassiliki A.; Polyzois, Vasilios D.; Arapoglou, Dimitrios K.; Papalois, Apostolos E.

    2011-01-01

    Management of Achilles tendon and heel area defects is a common challenge for the reconstructive surgeon due to the lack of soft tissue availability in that region. In this article, we present our experience in covering these defects by using the distal perforator propeller flaps based on the posterior tibial artery. Perforator flaps are based on cutaneous, small diameter vessels that originate from a main pedicle and perforate the fascia or muscle to reach the skin. Their development has followed the understanding of the blood supply from a source artery to the skin. Six patients (five males and one female) underwent reconstruction by using the posterior tibial artery distal perforator flap for covering defects in the distal Achilles tendon region in patients with and without diabetes mellitus. Postoperative complications included a hypertrophic scar formation in one patient, partial marginal flap necrosis in another patient, and a wound infection in a third patient. All wounds were eventually healed by the last postoperative visit. In conclusion, perforator flaps based on the distal posterior tibial artery may be a reliable option for the coverage of small to moderate size defects of the Achilles tendon and heel area regions. PMID:22396820

  6. Nintendo Wii related Achilles tendon rupture: first reported case and literature review of motion sensing video game injuries.

    PubMed

    Singh, Rohit; Manoharan, Gopikanthan; Moores, Thomas Steven; Patel, Amit

    2014-05-14

    Achilles tendon ruptures tend to occur more commonly in healthy men between the ages of 30 and 50 years who have had no previous injury or problem reported in the affected leg. The injury is usually due to sudden forced plantar flexion of the foot, unexpected dorsiflexion of the foot and violent dorsiflexion of a plantar flexed foot, all of which occur during high impact activities. We present the first reported case of interactive activity with Nintendo Wii games that have resulted in Achilles tendon rupture in a 46-year-old man. There have been no previous reports of Achilles tendon rupture with Nintendo Wii usage; it is a relatively uncommon mode of injury and is rare in terms of epidemiology of motion sensing video game injuries.

  7. [Influence of Achilles tendon vibration on the human vertical posture during standing with asymmetrical leg loading].

    PubMed

    Kazennikov, O V; Kireeva, T B; Shlykov, V Iu

    2014-01-01

    The shift of center of pressure (CP) of body and CP of each leg was studied during Achilles tendon vibration of one or both legs while subject was standing with symmetrical load on the legs or with the load transferred on one leg. The CP shift of standing subject during unilateral Achilles tendon vibration depended both on the side of the tendon vibration and on the leg load. When standing with a load transferred on one leg the shift of common CP was larger than when the vibration was applied to the loaded leg. The CP shift of one leg was greater if the vibration, and the load was applied to it. Vibration of unloaded leg caused a CP shift in the contralateral loaded leg. In this case, the vibration of left unloaded leg caused no noticeable CP shift of left leg, while the vibration of the unloaded right leg caused CP shift of right foot. In the same conditions of load and vibration the CP displacement of right leg was larger than the CP shift of left foot. It can be assumed that the change in the load on the leg and unilateral vibration of leg muscles change of the internal representation of the vertical body axis, which affects the CP position of one leg during the muscles vibration.

  8. A hybrid method for computing achilles tendon moment arm using ultrasound and motion analysis.

    PubMed

    Manal, Kurt; Cowder, Justin D; Buchanan, Thomas S

    2010-05-01

    In this article, we outline a method for computing Achilles tendon moment arm. The moment arm is computed from data collected using two reliable measurement instruments: ultrasound and video-based motion capture. Ultrasound is used to measure the perpendicular distance from the surface of the skin to the midline of the tendon. Motion capture is used to determine the perpendicular distance from the bottom of the probe to the ankle joint center. The difference between these two measures is the Achilles tendon moment arm. Unlike other methods, which require an angular change in joint position to approximate the moment arm, the hybrid method can be used to compute the moment arm directly at a specific joint angle. As a result, the hybrid method involves fewer error-prone measurements and the moment arm can be computed at the limits of the joint range of motion. The method is easy to implement and uses modalities that are less costly and more accessible than MRI. Preliminary testing using a lamb shank as a surrogate for a human ankle revealed good accuracy (3.3% error). We believe the hybrid method outlined here can be used to measure subject-specific moment arms in vivo and thus will potentially benefit research projects investigating ankle mechanics.

  9. Surgical versus conservative treatment following acute rupture of the Achilles tendon: is there a pedobarographic difference?

    PubMed Central

    Karaaslan, Fatih; Mermerkaya, Musa Uğur; Çıraklı, Alper; Karaoğlu, Sinan; Duygulu, Fuat

    2016-01-01

    Introduction Controversy remains regarding the optimal treatment method and postoperative rehabilitation of acute Achilles tendon ruptures. In this study, pedobarographic assessments of surgical and conservative treatments were compared. Material and methods A prospective assessment was made of 16 patients (eight surgical, eight conservative) and eight healthy controls using a plantar pressure measurement system. Biomechanical gait parameters were obtained using the Footscan dynamic gait analysis system. Kruskal–Wallis and Mann–Whitney U-tests were used for the evaluation of data. Results Nineteen males and five females were assessed, with an average age of 42.0±11.9 years. Follow-up was completed in 16 patients. No statistically significant difference was determined between the two treatment groups with regard to the gait analysis, but a difference was observed with the control group (P<0.001). All patients were able to resume their prior activities after 6 months and regained normal ranges of motion, with a high rate of satisfaction. Most of the patients (75%) were able to return to their pre-injury level of activities. Conclusion Satisfactory results were obtained through conservative treatment of acute ruptures of the Achilles tendon. No significant differences or complications were observed in the group managed conservatively versus the group treated surgically. Further studies including 3D gait analyses and tendon biomechanical research are required to further investigate this issue. PMID:27621640

  10. Depth-dependent variations in Achilles tendon deformations with age are associated with reduced plantarflexor performance during walking.

    PubMed

    Franz, Jason R; Thelen, Darryl G

    2015-08-01

    The anatomical arrangement of the Achilles tendon (AT), with distinct fascicle bundles arising from the gastrocnemius and soleus muscles, may facilitate relatively independent behavior of the triceps surae muscles. A reduced capacity for sliding between adjacent tendon fascicles with age may couple gastrocnemius and soleus muscle behavior, thereby potentially contributing to diminished plantarflexor performance commonly observed in old adults. Nine healthy young (mean age, 23.9 yr) and eight healthy old (69.9 yr) adults walked at three speeds (0.75, 1.00, and 1.25 m/s) on a force-sensing treadmill. We coupled dynamic ultrasound imaging of the free AT with motion capture and inverse dynamic analyses to compute, in part: 1) depth-dependent variations in AT tissue displacements and elongations and 2) net ankle joint kinetics during push-off. The difference in displacements between superficial and deep AT regions, and in their corresponding elongations, did not differ between old and young adults at the slower two walking speeds (P > 0.61). However, old adults walked with 41% smaller depth-dependent variations in free AT displacements and elongations at 1.25 m/s (P = 0.02). These more uniform tendon deformations in old adults most strongly correlated with reduced peak ankle moment (R(2) = 0.40), but also significantly correlated with reduced peak power generation (R(2) = 0.15) and positive ankle work during push-off (R(2) = 0.19) (P > 0.01). Our findings: 1) demonstrate a potential role for nonuniform AT deformations in governing gastrocnemius and soleus muscle-tendon function and 2) allude to altered tendon behavior that may contribute to the age-related reduction in plantarflexor performance during walking.

  11. Reliability of the Achilles tendon tap reflex evoked during stance using a pendulum hammer.

    PubMed

    Mildren, Robyn L; Zaback, Martin; Adkin, Allan L; Frank, James S; Bent, Leah R

    2016-01-01

    The tendon tap reflex (T-reflex) is often evoked in relaxed muscles to assess spinal reflex circuitry. Factors contributing to reflex excitability are modulated to accommodate specific postural demands. Thus, there is a need to be able to assess this reflex in a state where spinal reflex circuitry is engaged in maintaining posture. The aim of this study was to determine whether a pendulum hammer could provide controlled stimuli to the Achilles tendon and evoke reliable muscle responses during normal stance. A second aim was to establish appropriate stimulus parameters for experimental use. Fifteen healthy young adults stood on a forceplate while taps were applied to the Achilles tendon under conditions in which postural sway was constrained (by providing centre of pressure feedback) or unconstrained (no feedback) from an invariant release angle (50°). Twelve participants repeated this testing approximately six months later. Within one experimental session, tap force and T-reflex amplitude were found to be reliable regardless of whether postural sway was constrained (tap force ICC=0.982; T-reflex ICC=0.979) or unconstrained (tap force ICC=0.968; T-reflex ICC=0.964). T-reflex amplitude was also reliable between experimental sessions (constrained ICC=0.894; unconstrained ICC=0.890). When a T-reflex recruitment curve was constructed, optimal mid-range responses were observed using a 50° release angle. These results demonstrate that reliable Achilles T-reflexes can be evoked in standing participants without the need to constrain posture. The pendulum hammer provides a simple method to allow researchers and clinicians to gather information about reflex circuitry in a state where it is involved in postural control.

  12. Ipsi- and contralateral H-reflexes and V-waves after unilateral chronic Achilles tendon vibration.

    PubMed

    Lapole, Thomas; Canon, Francis; Pérot, Chantal

    2013-09-01

    Chronic Achilles tendon vibration has previously shown its effectiveness in improving plantar flexor's strength and activation capacities. The present study investigated the related neural mechanisms by analyzing H-reflexes and V-waves of the soleus (SOL) and gastrocnemii (GM gastrocnemius medialis; GL gastrocnemius lateralis) muscles under maximal isometric plantar flexion. Moreover, recordings were conducted bilaterally to address potential crossed effects. 11 subjects were engaged in this study. Maximal voluntary contraction and superimposed H-reflexes and V-waves were quantified in both legs at baseline (PRE) and 2 weeks later to verify repeatability of data (CON). Then, subjects were retested after 14 days of daily unilateral Achilles tendon vibration (VIB; 1 h per day; frequency: 50 Hz). No changes were reported between PRE and CON data. In the VIB condition, there was an increase in MVC for both the vibrated (+9.1 %; p = 0.016) and non-vibrated (+10.2 %; p = 0.009) legs. The H-reflex increased by a mean 25 % in the vibrated SOL (p < 0.001), while it remained unchanged for the contralateral side (p = 0.531). The SOL V-wave also increased in the vibrated limb (+43.3 %; p < 0.001), as well as in the non-vibrated one (+41.9 %; p = 0.006). Furthermore, the GM V-wave increased by 37.8 % (p = 0.081) in the vibrated side and by 39.4 % (p = 0.03) in the non-vibrated side. However, no changes were reported for the GL muscles. While the present study confirmed the strength gains induced by chronic Achilles tendon vibration, the results indicated a cross-education phenomenon with differences in neural adaptations between the vibrated leg and non-vibrated leg.

  13. 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.

  14. Medial malleolus fracture of the ankle combined with rupture of the Achilles tendon

    PubMed Central

    Lu, Jike; Maruo Holledge, Masumi

    2016-01-01

    A 59-year-old man fell off a 60-cm-high step, with his ankle in a twisted position, and sustained a closed fracture of the medial malleolus, with an ipsilateral complete Achilles tendon (TA) rupture. The TA rupture was initially missed but diagnosed by ultrasound examination, 2 weeks post-operatively. The ankle fracture was diagnosed from routine radiographs. Such a combination of injuries has been reported infrequently in the literature, but significant similarities have been described in the mechanism of injury and fracture patterns. Nevertheless, three of five reported cases with combined medial malleolus fractures were initially misdiagnosed. PMID:27141047

  15. Sport-Specific Capacity to Use Elastic Energy in the Patellar and Achilles Tendons of Elite Athletes

    PubMed Central

    Wiesinger, Hans-Peter; Rieder, Florian; Kösters, Alexander; Müller, Erich; Seynnes, Olivier R.

    2017-01-01

    Introduction: During running and jumping activities, elastic energy is utilized to enhance muscle mechanical output and efficiency. However, training-induced variations in tendon spring-like properties remain under-investigated. The present work extends earlier findings on sport-specific profiles of tendon stiffness and cross-sectional area to examine whether years of distinct loading patterns are reflected by tendons' ability to store and return energy. Methods:Ultrasound scans were performed to examine the morphological features of knee extensor and plantar flexor muscle-tendon units in elite ski jumpers, distance runners, water polo players, and sedentary controls. Tendon strain energy and hysteresis were measured with combined motion capture, ultrasonography, and dynamometry. Results: Apart from the fractional muscle-to-tendon cross-sectional area ratio being lower in the knee extensors of ski jumpers (−31%) and runners (−33%) than in water polo players, no difference in the considered muscle-tendon unit morphological features was observed between groups. Similarly, no significant difference in tendon energy storage or energy return was detected between groups. In contrast, hysteresis was lower in the patellar tendon of ski jumpers (−33%) and runners (−30%) compared to controls, with a similar trend for the Achilles tendon (significant interaction effect and large effect sizes η2 = 0.2). Normalized to body mass, the recovered strain energy of the patellar tendon was ~50% higher in ski jumpers than in water polo players and controls. For the Achilles tendon, recovered strain energy was ~40% higher in ski jumpers and runners than in controls. Discussion: Advantageous mechanical properties related to tendon spring-like function are observed in elite athletes whose sport require effective utilization of elastic energy. However, the mechanisms underpinning the better tendon capacity of some athletes to retain elastic energy could not be ascribed to

  16. Sport-Specific Capacity to Use Elastic Energy in the Patellar and Achilles Tendons of Elite Athletes.

    PubMed

    Wiesinger, Hans-Peter; Rieder, Florian; Kösters, Alexander; Müller, Erich; Seynnes, Olivier R

    2017-01-01

    Introduction: During running and jumping activities, elastic energy is utilized to enhance muscle mechanical output and efficiency. However, training-induced variations in tendon spring-like properties remain under-investigated. The present work extends earlier findings on sport-specific profiles of tendon stiffness and cross-sectional area to examine whether years of distinct loading patterns are reflected by tendons' ability to store and return energy. Methods:Ultrasound scans were performed to examine the morphological features of knee extensor and plantar flexor muscle-tendon units in elite ski jumpers, distance runners, water polo players, and sedentary controls. Tendon strain energy and hysteresis were measured with combined motion capture, ultrasonography, and dynamometry. Results: Apart from the fractional muscle-to-tendon cross-sectional area ratio being lower in the knee extensors of ski jumpers (-31%) and runners (-33%) than in water polo players, no difference in the considered muscle-tendon unit morphological features was observed between groups. Similarly, no significant difference in tendon energy storage or energy return was detected between groups. In contrast, hysteresis was lower in the patellar tendon of ski jumpers (-33%) and runners (-30%) compared to controls, with a similar trend for the Achilles tendon (significant interaction effect and large effect sizes η(2) = 0.2). Normalized to body mass, the recovered strain energy of the patellar tendon was ~50% higher in ski jumpers than in water polo players and controls. For the Achilles tendon, recovered strain energy was ~40% higher in ski jumpers and runners than in controls. Discussion: Advantageous mechanical properties related to tendon spring-like function are observed in elite athletes whose sport require effective utilization of elastic energy. However, the mechanisms underpinning the better tendon capacity of some athletes to retain elastic energy could not be ascribed to intrinsic or

  17. Gastric pentadecapeptide BPC 157 accelerates healing of transected rat Achilles tendon and in vitro stimulates tendocytes growth.

    PubMed

    Staresinic, M; Sebecic, B; Patrlj, L; Jadrijevic, S; Suknaic, S; Perovic, D; Aralica, G; Zarkovic, N; Borovic, S; Srdjak, M; Hajdarevic, K; Kopljar, M; Batelja, L; Boban-Blagaic, A; Turcic, I; Anic, T; Seiwerth, S; Sikiric, P

    2003-11-01

    In studies intended to improve healing of transected Achilles tendon, effective was a stable gastric pentadecapeptide BPC 157 (GEPPPGKPADDAGLV, M.W. 1419). Currently in clinical trials for inflammatory bowel disease (PLD-116, PL 14736, Pliva), it ameliorates internal and external wound healing. In rats, the right Achilles tendon transected (5 mm proximal to its calcaneal insertion) presents with a large tendon defect between cut ends. Agents (/kg b.w., i.p., once time daily) (BPC 157 (dissolved in saline, with no carrier addition) (10 microg, 10 ng or 10 pg) or saline (5.0 ml)), were firstly applied at 30 min after surgery, the last application at 24 h before autopsy. Achilles functional index (AFI) was assessed once time daily. Biomechanical, microscopical and macroscopical assessment was on day 1, 4, 7, 10 and 14. Controls generally have severely compromised healing. In comparison, pentadecapeptide BPC 157 fully improves recovery: (i) biomechanically, increased load of failure, load of failure per area and Young's modulus of elasticity; (ii) functionally, significantly higher AFI-values; (iii) microscopically, more mononuclears and less granulocytes, superior formation of fibroblasts, reticulin and collagen; (iv) macroscopically, smaller size and depth of tendon defect, and subsequently the reestablishment of full tendon integrity. Likewise, unlike TGF-beta, pentadecapeptide BPC 157, presenting with no effect on the growth of cultured cell of its own, consistently opposed 4-hydroxynonenal (HNE), a negative modulator of the growth. HNE-effect is opposed in both combinations: BPC 157+HNE (HNE growth inhibiting effect reversed into growth stimulation of cultured tendocytes) and HNE+BPC 157(abolished inhibiting activity of the aldehyde), both in the presence of serum and serum deprived conditions. In conclusion, these findings, particularly, Achilles tendon transection fully recovered in rats, peptide stability suitable delivery, usefully favor gastric

  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 Central

    Zellers, Jennifer A.; Cortes, Daniel H.

    2016-01-01

    Introduction 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). Subject Description The subject is a 26 year-old, female basketball coach who sustained an Achilles tendon rupture and was managed non-surgically. Outcome 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. Discussion This case report

  19. The modified Bosworth technique for the treatment of acute traumatic Achilles tendon rupture.

    PubMed

    Efstathopoulos, N; Agoropoulos, Z; Papachristou, G; Karachalios, G G; Kokorogiannis, K; Kaloudis, J

    1996-09-01

    Between 1983 and 1994, 15 patients (range 18 to 62 years) with acute traumatic Achilles tendon rupture, were treated surgically in our Department. We employed a modified Bosworth technique. The modifications were the use of a shorter strip of tendon and more secure fixation of the proximal and distal stump, than the original Bosworth technique. Postoperatively an above - knee plaster cast was applied with the knee flexed 30°-40° and the foot in a relaxed equinus position. The plaster cast was changed to a below - knee after 4 weeks and the foot gradually dorsiflexed to a neutral position until the 8th week, and then the plaster cast was removed. No patient had wound separation, infection or skin sloughs. After an average follow-up of 9 years, no rerupture has been reported and all the patients have returned to their pre injury activities.

  20. Changes in ADC Caused by Tensile Loading of Rabbit Achilles Tendon: Evidence for Water Transport

    NASA Astrophysics Data System (ADS)

    Han, S.; Gemmell, S. J.; Helmer, K. G.; Grigg, P.; Wellen, J. W.; Hoffman, A. H.; Sotak, C. H.

    2000-06-01

    Water diffusion measurements were performed on rabbit Achilles tendons during static tensile loading and tendons in an unloaded state. The apparent diffusion coefficient (ADC) was measured along two directions: parallel and perpendicular to the long axis of the tendon. Tendons were studied after being prepared in two ways: (a) after being stored frozen in phosphate-buffered saline (PBS) and (b) freshly isolated. Statistically significant directional anisotropy was observed in the ADC in all tendons. The ADC was significantly greater in the direction parallel to the long axis of the tendon than in the perpendicular direction. The anisotropy is attributed to the greater restrictions seen by the water molecules in the perpendicular direction and is consistent with the known geometry of the tendon. Storage in PBS caused tendons to swell. This increased the ADC measured along both directions and reduced the anisotropy. The existence of anisotropy in the ADC was not related to the orientation of the specimen in the magnet. The ADC increased along both directions following the application of a 5-N tensile load; the increase was greatest along the perpendicular axis of the tendon. In order to determine whether load-related changes in the ADC reflected changes in interfibrilar spacing, we used electron microscopy to measure load-related changes in fibril spacing. Load-related changes in fiber spacing could not account for the observed changes in the ADC. The increase in ADC caused by loading was attributed to the extrusion of tendon water into a bulk phase along the outside surface of the tendon. In PBS-stored samples, enough fluid was extruded that it could be visualized. The transient response of the ADC to a 5-N tensile load was also studied. The absolute ADC in both directions increased with loading and recovered to baseline upon unloading. The transient changes in ADC, for both loading and unloading, had a mean time constant of approximately 15 min. The magnitude of

  1. Treatment Algorithm for Chronic Achilles Tendon LesionsReview of the Literature and Proposal of a New Classification.

    PubMed

    Buda, Roberto; Castagnini, Francesco; Pagliazzi, Gherardo; Giannini, Sandro

    2017-03-01

    Chronic Achilles tendon lesions (CATLs) ensue from a neglected acute rupture or a degenerated tendon. Surgical treatment is usually required. The current English literature (PubMed) about CATLs was revised, and particular emphasis was given to articles depicting CATL classification. The available treatment algorithms are based on defect size. We propose the inclusion of other parameters, such as tendon degeneration, etiology, and time from injury to surgery. Partial lesions affecting less than (I stage) or more than (II stage) half of the tendon should be treated conservatively for healthy tendons, within 12 weeks of injury. In II stage complex cases, an end-to-end anastomosis is required. Complete lesions inferior to 2 cm should be addressed by an end-to-end anastomosis, with a tendon transfer in the case of tendon degeneration. Lesions measuring 2 to 5 cm require a turndown flap and a V-Y tendinous flap in the case of a good-quality tendon; degenerated tendons may require a tendon transfer. Lesions larger than 5 cm should be treated using two tendon transfers and V-Y tendinous flaps. A proper algorithm should be introduced to calibrate the surgical procedures. In addition to tendon defect size, tendon degeneration, etiology of the lesion, and time from injury to surgery are crucial factors that should be considered in the surgical planning.

  2. Informing tendon tissue engineering with embryonic development.

    PubMed

    Glass, Zachary A; Schiele, Nathan R; Kuo, Catherine K

    2014-06-27

    Tendon is a strong connective tissue that transduces muscle-generated forces into skeletal motion. In fulfilling this role, tendons are subjected to repeated mechanical loading and high stress, which may result in injury. Tissue engineering with stem cells offers the potential to replace injured/damaged tissue with healthy, new living tissue. Critical to tendon tissue engineering is the induction and guidance of stem cells towards the tendon phenotype. Typical strategies have relied on adult tissue homeostatic and healing factors to influence stem cell differentiation, but have yet to achieve tissue regeneration. A novel paradigm is to use embryonic developmental factors as cues to promote tendon regeneration. Embryonic tendon progenitor cell differentiation in vivo is regulated by a combination of mechanical and chemical factors. We propose that these cues will guide stem cells to recapitulate critical aspects of tenogenesis and effectively direct the cells to differentiate and regenerate new tendon. Here, we review recent efforts to identify mechanical and chemical factors of embryonic tendon development to guide stem/progenitor cell differentiation toward new tendon formation, and discuss the role this work may have in the future of tendon tissue engineering.

  3. Informing tendon tissue engineering with embryonic development

    PubMed Central

    Glass, Zachary A.; Schiele, Nathan R.; Kuo, Catherine K.

    2014-01-01

    Tendon is a strong connective tissue that transduces muscle-generated forces into skeletal motion. In fulfilling this role, tendons are subjected to repeated mechanical loading and high stress, which may result in injury. Tissue engineering with stem cells offers the potential to replace injured/damaged tissue with healthy, new living tissue. Critical to tendon tissue engineering is the induction and guidance of stem cells towards the tendon phenotype. Typical strategies have relied on adult tissue homeostatic and healing factors to influence stem cell differentiation, but have yet to achieve tissue regeneration. A novel paradigm is to use embryonic developmental factors as cues to promote tendon regeneration. Embryonic tendon progenitor cell differentiation in vivo is regulated by a combination of mechanical and chemical factors. We propose that these cues will guide stem cells to recapitulate critical aspects of tenogenesis and effectively direct the cells to differentiate and regenerate new tendon. Here, we review recent efforts to identify mechanical and chemical factors of embryonic tendon development to guide stem/progenitor cell differentiation toward new tendon formation, and discuss the role this work may have in the future of tendon tissue engineering. PMID:24484642

  4. Comparison of Semi-Invasive "Internal Splinting" and Open Suturing Techniques in Achilles Tendon Rupture Surgery.

    PubMed

    Sarman, Hakan; Muezzinoglu, Umit Sefa; Memisoglu, Kaya; Aydin, Adem; Atmaca, Halil; Baran, Tuncay; Odabas Ozgur, Bahar; Ozgur, Turgay; Kantar, Cengizhan

    2016-01-01

    The goal of the present study was to evaluate the semi-invasive "internal splinting" (SIIS) method for repair of Achilles tendon rupture relative to open repair with Krakow sutures. Efficacy was evaluated based on the clinical and functional outcomes, postoperative magnetic resonance imaging measurements, isokinetic results, and surgical complication rates. Functional measurements included the Thermann and American Orthopaedic Foot and Ankle Society (AOFAS) ankle scores, bilateral ankle dorsiflexion, and plantar flexion measurements. Magnetic resonance imaging was used to compare the bilateral length and thickness of each Achilles tendon. The isokinetic outcomes were evaluated using a Biodex System 3 dynamometer. Of the 45 patients meeting the inclusion criteria, 24 were treated by SIIS and 21 by the open Krackow suture technique. The mean follow-up time for all patients was 43.7 (range 6 to 116) months. In the SIIS group, patients returned to normal daily activities after 7.2 (range 6 to 8) weeks compared with 14.3 (range 12 to 15) weeks in the open surgery group. The AOFAS ankle scores were 93.5 (range 82 to 100) points in the open repair group and 96.2 (range 86 to 100) points in the SIIS group. The Thermann scores were 80.4 (range 53 to 91) points for the open repair group and 87.9 (range 81 to 100) points for the SIIS method. The mean Achilles length on the operated side measured using magnetic resonance imaging was 175.06 (range 110 to 224) mm and 177.76 (range 149 to 214) mm for the open surgery and SIIS groups, respectively. Sensory impairment in the territory of the sural nerve was identified in 1 patient immediately after SIIS surgery, although this defect had completely resolved within 12 months. SIIS yielded better outcomes relative to the open surgery group according to the isokinetic measurements. Taken together, these data indicate the SIIS method for Achilles tendon ruptures performed better in terms of both functional and objective outcomes

  5. Acute postural modulation of the soleus H-reflex after Achilles tendon vibration.

    PubMed

    Lapole, Thomas; Canon, Francis; Pérot, Chantal

    2012-08-15

    Alteration of Soleus (SOL) H-reflex has been reported after prolonged vibratory exposure and it was hypothesized that presynaptic inhibition, known to depress the H-reflex during vibration, largely contributed to the H-reflex changes. To confirm this hypothesis, the purpose of the present study was to quantify the SOL H-reflex changes between sitting and standing positions (postural modulation) with or without the after-effects of 1h of Achilles tendon vibration. Indeed, postural modulation of the SOL H-reflex has been reported to inform on the level of presynaptic inhibition exerted on Ia afferents. SOL H-reflex and M waves were measured in healthy voluntary subjects in both sitting and standing positions before and after 1h of Achilles vibration (frequency: 50 Hz) applied in sitting position (vibration group, n=11) or before and after 1h of sitting position only (control group, n=6). SOL H(max)/M(max) ratios were calculated. Furthermore, in order to quantify presynaptic inhibition induced by prolonged vibration, an index of SOL H-reflex postural modulation was calculated as the standing H(max)/M(max) ratio relative to the sitting one. After 1h of Achilles tendon vibration, a significant decrease in the SOL H(max)/M(max) ratio was observed both in sitting and standing positions (p<0.05). However, the decrease was more pronounced in the standing position, leading to a significant decrease of the index of SOL H-reflex postural modulation. Those results suggest that presynaptic inhibition could have largely contributed to the H-reflex decrease observed after one bout of vibration.

  6. The plantaris tendon and a potential role in mid-portion Achilles tendinopathy: an observational anatomical study

    PubMed Central

    van Sterkenburg, Maayke N; Kerkhoffs, Gino M M J; Kleipool, Roeland P; Niek van Dijk, C

    2011-01-01

    The source of pain and the background to the pain mechanisms associated with mid-portion Achilles tendinopathy have not yet been clarified. Intratendinous degenerative changes are most often addressed when present. However, it is questionable if degeneration of the tendon itself is the main cause of pain. Pain is often most prominent on the medial side, 2–7 cm from the insertion onto the calcaneus. The medial location of the pain has been explained to be caused by enhanced stress on the calcaneal tendon due to hyperpronation. However, on this medial side the plantaris tendon is also located. It has been postulated that the plantaris tendon might play a role in these medially located symptoms. To our knowledge, the exact anatomy and relationship between the plantaris- and calcaneal tendon at the level of complaints have not been anatomically assessed. This was the purpose of our study. One-hundred and seven lower extremities were dissected. After opening the superficial fascia and paratendon, the plantaris tendon was bluntly released from the calcaneal tendon moving distally. The incidence of the plantaris tendon, its course, site of insertion and possible connections were documented. When with manual force the plantaris tendon could not be released, it was defined as a ‘connection’ with the calcaneal tendon. In all specimens a plantaris tendon was identified. Nine different sites of insertion were found, mostly medial and fan-shaped onto the calcaneus. In 11 specimens (10%) firm connections were found at the level of the calcaneal tendon mid-portion. Clinical and histological studies are needed to confirm the role of the plantaris tendon in mid-portion Achilles tendinopathy. PMID:21323916

  7. Acute effects of Achilles tendon vibration on soleus and tibialis anterior spinal and cortical excitability.

    PubMed

    Lapole, Thomas; Deroussen, François; Pérot, Chantal; Petitjean, Michel

    2012-08-01

    Prolonged vibration is known to alter muscle performance. Attenuation of Ia afferent efficacy is the main mechanism suggested. However, changes in motor cortex excitability could also be hypothesized. The purpose of the present study was therefore to analyze the acute and outlasting effects of 1 h of Achilles tendon vibration (frequency, 50 Hz) on the soleus (SOL) and tibialis anterior (TA) neuromuscular excitability. Spinal excitability was investigated by means of H-reflexes and F-waves while cortical excitability was characterized by motor evoked potentials (MEPs) obtained by transcranial magnetic stimulation. Twelve subjects performed the experimental procedures 3 times: at the beginning of the testing session (PRE), immediately after 1 h of Achilles tendon vibration (POST), and 1 h after the end of vibration (POST-1H). Prolonged vibration led to acute reduced H-reflex amplitudes for SOL only (46.9% ± 7.7% vs. 32.8% ± 7%; p = 0.006). Mainly presynaptic inhibition mechanisms were thought to be involved because of unchanged F-wave persistence and amplitude mean values, suggesting unaffected motoneuronal excitability. While no acute effects were reported for SOL and TA cortical excitability, both muscles were characterized by an outlasting increase in their MEP amplitude (0.64 ± 0.2 mV vs. 0.43 ± 0.18 mV and 2.17 ± 0.56 mV vs. 1.26 ± 0.36 mV, respectively; p < 0.05). The high modulation of Ia afferent input by vibration led to changes in motor cortex excitability that could contribute to the enhancement in muscular activation capacities reported after chronic use of tendon vibration.

  8. Effects of repeated Achilles tendon vibration on triceps surae stiffness and reflex excitability.

    PubMed

    Lapole, Thomas; Pérot, Chantal

    2011-02-01

    Clinical studies frequently report an increase in stiffness and a loss of range of motion at joints placed in disuse or immobilization. This is notably the case for subjects maintained in bed for a long period, whilst their joints are not affected. Recently we documented on healthy subjects the benefit in terms of force and activation capacities of the triceps surae offered by vibrations applied to the Achilles tendon. Knowing that stiffness changes may contribute to force changes, the aim of the present study was to investigate the effects of tendon vibration on the triceps surae stiffness of healthy subjects. The vibration program consisted in 14 days of 1h daily Achilles tendon vibration applied at rest. Nineteen healthy students were involved in this study. Before and at the end of the vibration program, musculo-tendinous stiffness in active conditions was determined by use of a quick-release test. Passive stiffness was also analyzed by a flexibility test: passive torque-angle relationships were established from maximal plantar-flexion to maximal dorsiflexion. Passive stiffness indexes at 10°, 15° and 20° dorsiflexion were defined as the slope of the relationships at the corresponding angle. Tendinous reflex, influenced by stiffness values, was also investigated as well as the H reflex to obtain an index of the central reflex excitability. After the program, musculo-tendinous stiffness was significantly decreased (p=.01). At the same time, maximal passive dorsiflexion was increased (p=.005) and passive stiffness indexes at 10°, 15° and 20° dorsiflexion decreased (p<.001; p<.001 and p=.011, respectively). Tendinous reflex also significantly decreased. As the triceps surae parameters are diminished after the vibration program, it could be beneficial to immobilized persons as hypo-activity is known to increase muscular stiffness.

  9. Rabbit Achilles tendon full transection model - wound healing, adhesion formation and biomechanics at 3, 6 and 12 weeks post-surgery.

    PubMed

    Meier Bürgisser, Gabriella; Calcagni, Maurizio; Bachmann, Elias; Fessel, Gion; Snedeker, Jess G; Giovanoli, Pietro; Buschmann, Johanna

    2016-09-15

    After tendon rupture repair, two main problems may occur: re-rupture and adhesion formation. Suitable non-murine animal models are needed to study the healing tendon in terms of biomechanical properties and extent of adhesion formation. In this study 24 New Zealand White rabbits received a full transection of the Achilles tendon 2 cm above the calcaneus, sutured with a 4-strand Becker suture. Post-surgical analysis was performed at 3, 6 and 12 weeks. In the 6-week group, animals received a cast either in a 180 deg stretched position during 6 weeks (adhesion provoking immobilization), or were re-casted with a 150 deg position after 3 weeks (adhesion inhibiting immobilization), while in the other groups (3 and 12 weeks) a 180 deg position cast was applied for 3 weeks. Adhesion extent was analyzed by histology and ultrasound. Histopathological scoring was performed according to a method by Stoll et al. (2011), and the main biomechanical properties were assessed. Histopathological scores increased as a function of time, but did not reach values of healthy tendons after 12 weeks (only around 15 out of 20 points). Adhesion provoking immobilization led to an adhesion extent of 82.7±9.7%, while adhesion inhibiting immobilization led to 31.9±9.8% after 6 weeks. Biomechanical properties increased over time, however, they did not reach full strength nor elastic modulus at 12 weeks post-operation. Furthermore, the rabbit Achilles tendon model can be modulated in terms of adhesion formation to the surrounding tissue. It clearly shows the different healing stages in terms of histopathology and offers a suitable model regarding biomechanics because it exhibits similar biomechanics as the human flexor tendons of the hand.

  10. Rabbit Achilles tendon full transection model – wound healing, adhesion formation and biomechanics at 3, 6 and 12 weeks post-surgery

    PubMed Central

    Meier Bürgisser, Gabriella; Calcagni, Maurizio; Bachmann, Elias; Fessel, Gion; Snedeker, Jess G.; Giovanoli, Pietro

    2016-01-01

    ABSTRACT After tendon rupture repair, two main problems may occur: re-rupture and adhesion formation. Suitable non-murine animal models are needed to study the healing tendon in terms of biomechanical properties and extent of adhesion formation. In this study 24 New Zealand White rabbits received a full transection of the Achilles tendon 2 cm above the calcaneus, sutured with a 4-strand Becker suture. Post-surgical analysis was performed at 3, 6 and 12 weeks. In the 6-week group, animals received a cast either in a 180 deg stretched position during 6 weeks (adhesion provoking immobilization), or were re-casted with a 150 deg position after 3 weeks (adhesion inhibiting immobilization), while in the other groups (3 and 12 weeks) a 180 deg position cast was applied for 3 weeks. Adhesion extent was analyzed by histology and ultrasound. Histopathological scoring was performed according to a method by Stoll et al. (2011), and the main biomechanical properties were assessed. Histopathological scores increased as a function of time, but did not reach values of healthy tendons after 12 weeks (only around 15 out of 20 points). Adhesion provoking immobilization led to an adhesion extent of 82.7±9.7%, while adhesion inhibiting immobilization led to 31.9±9.8% after 6 weeks. Biomechanical properties increased over time, however, they did not reach full strength nor elastic modulus at 12 weeks post-operation. Furthermore, the rabbit Achilles tendon model can be modulated in terms of adhesion formation to the surrounding tissue. It clearly shows the different healing stages in terms of histopathology and offers a suitable model regarding biomechanics because it exhibits similar biomechanics as the human flexor tendons of the hand. PMID:27635037

  11. Tendon crimps and peritendinous tissues responding to tensional forces.

    PubMed

    Franchi, M; Quaranta, M; De Pasquale, V; Macciocca, M; Orsini, E; Trirè, A; Ottani, V; Ruggeri, A

    2007-01-01

    Tendons transmit forces generated from muscle to bone making joint movements possible. Tendon collagen has a complex supramolecular structure forming many hierarchical levels of association; its main functional unit is the collagen fibril forming fibers and fascicles. Since tendons are enclosed by loose connective sheaths in continuity with muscle sheaths, it is likely that tendon sheaths could play a role in absorbing/transmitting the forces created by muscle contraction. In this study rat Achilles tendons were passively stretched in vivo to be observed at polarized light microscope (PLM), scanning electron microscope (SEM) and transmission electron microscope (TEM). At PLM tendon collagen fibers in relaxed rat Achilles tendons ran straight and parallel, showing a periodic crimp pattern. Similarly tendon sheaths showed apparent crimps. At higher magnification SEM and TEM revealed that in each tendon crimp large and heterogeneous collagen fibrils running straight and parallel suddenly changed their direction undergoing localized and variable modifications. These fibril modifications were named fibrillar crimps. Tendon sheaths displayed small and uniform fibrils running parallel with a wavy course without any ultrastructural aspects of crimp. Since in passively stretched Achilles tendons fibrillar crimps were still observed, it is likely that during the tendon stretching, and presumably during the tendon elongation in muscle contraction, the fibrillar crimp may be the real structural component of the tendon crimp acting as shock absorber. The peritendinous sheath can be stretched as tendon, but is not actively involved in the mechanism of shock absorber as the fibrillar crimp. The different functional behaviour of tendons and sheaths may be due to the different structural and molecular arrangement of their fibrils.

  12. The effect of butyric acid with autogenous omental graft on healing of experimental Achilles tendon injury in rabbits

    PubMed Central

    Jahani, S; Moslemi, H. R.; Dehghan, M. M.; Sedaghat, R; Mazaheri Nezhad, R; Rezaee Moghaddam, D

    2015-01-01

    In this study, the role of local injection of butyric acid (BA) with autogenous omental graft was evaluated in healing of experimental Achilles tendon injury in rabbits. Nine adult male New Zealand rabbits were anesthetized and a partial thickness tenotomy was created on both hindlimbs. In treated group, omental graft was secured in place using BA soaked polygalactin 910 suture. In control group, the graft was sutured without BA. Butyric acid and normal saline were injected daily to treatment and control groups for three days, respectively. Based on the findings, on day 15 after injury, the tendon sections showed that healing rate in BA treated group was higher than that in control group. Furthermore, at days 28 and 45, comparison between BA treated and control groups demonstrated that BA increased the healing rate but with no significance. In summary, results of this study show that application of BA with autogenous omental graft can improve healing process of damaged Achilles tendon. PMID:27175160

  13. Procollagen markers in microdialysate can predict patient outcome after Achilles tendon rupture

    PubMed Central

    Alim, Md Abdul; Svedman, Simon; Edman, Gunnar

    2016-01-01

    Objective Patients who sustain acute Achilles tendon rupture (ATR) exhibit variable and mostly impaired long-term functional, and patient-reported outcomes. However, there exists a lack of early predictive markers of long-term outcomes to facilitate the development of improved treatment methods. The aim of this study was to assess markers of tendon callus production in patients with ATR in terms of outcome, pain, and fatigue. Study design and setting Prospective cohort study; level of evidence 2. Outpatient orthopaedic/sports medicine department. Patients A total of 65 patients (57 men, 8 women; mean age 41±7 years) with ATR were prospectively assessed. Assessments Markers of tendon callus production, procollagen type I N-terminal propeptide (PINP) and procollagen type III N-terminal propeptide (PIIINP), were assessed 2 weeks postoperatively using microdialysis followed by enzymatic quantification. Normalised procollagen levels (n-PINP and n-PIIINP) were calculated as the ratio of procollagen to total protein content. Pain and fatigue were assessed at 1 year using reliable questionnaires Achilles tendon Total Rupture Score (ATRS). Results Patients exhibited fatigue (77.6%) and pain (44.1%) to some extent. Higher levels of n-PINP (R=0.38, p=0.016) and n-PIIINP (R=0.33, p=0.046) were significantly associated with less pain in the limb. Increased concentrations of PINP (R=−0.47, p=0.002) and PIIINP (R=−0.37, p=0.024) were related to more self-reported fatigue in the leg. The results were corroborated by multiple linear regression analyses. Conclusions Assessment of procollagen markers in early tendon healing can predict long-term patient-reported outcomes after ATR. These novel findings suggest that procollagen markers could be used to facilitate the development of improved treatment methods in patients who sustain ATR. Trial registration numbers NCT01317160: Results. NCT02318472: Pre-results. PMID:27900179

  14. Study of Bone Marrow Mesenchymal and Tendon-Derived Stem Cells Transplantation on the Regenerating Effect of Achilles Tendon Ruptures in Rats

    PubMed Central

    Al-ani, Mohanad Kh; Xu, Kang; Sun, Yanjun; Pan, Lianhong; Xu, ZhiLing; Yang, Li

    2015-01-01

    Comparative therapeutic significance of tendon-derived stem cells (TDSCs) and bone marrow mesenchymal stem cells (BMSCs) transplantation to treat ruptured Achilles tendon was studied. Three groups of SD rats comprising 24 rats each, designated as TDSCs and BMSCs, and nontreated were studied for regenerative effects through morpho-histological evaluations and ultimate failure load. For possible mechanism in tendon repair/regeneration through TDSCs and BMSCs, we measured Collagen-I (Col-I), Col-III gene expression level by RT-PCR, and Tenascin-C expression via immunofluorescent assay. TDSCs showed higher agility in tendon healing with better appearance density and well-organized longitudinal fibrous structure, though BMSCs also showed positive effects. Initially the ultimate failure load was considerably higher in TDSCs than other two study groups during the weeks 1 and 2, but at week 4 it attained an average or healthy tendon strength of 30.2 N. Similar higher tendency in Col-I/III gene expression level during weeks 1, 2, and 4 was observed in TDSCs treated group with an upregulation of 1.5-fold and 1.1-fold than the other two study groups. Immunofluorescent assay revealed higher expression of Tenascin-C in TDSCs at week 1, while both TDSCs and BMSCs treated groups showed detectable CM-Dil-labelled cells at week 4. Compared with BMSCs, TDSCs showed higher regenerative potential while treating ruptured Achilles tendons in rats. PMID:26339252

  15. A DELPHI STUDY OF RISK FACTORS FOR ACHILLES TENDINOPATHY- OPINIONS OF WORLD TENDON EXPERTS

    PubMed Central

    Watson, Paul J.; Barry, Simon

    2016-01-01

    Background and Purpose Achilles tendinopathy can be a debilitating chronic condition for both active and inactive individuals. The identification of risk facors is important both in preventing but also treating tendinopathy, many factors have been proposed but there is a lack of primary epidemiological data. The purpose of this study was to develop a statement of expert consensus on risk factors for Achilles tendinopathy in active and sedentary patient populations to inform a primary epidemiological study. Study design Delphi study Methods and Measures An online Delphi study was completed inviting participation from world tendon experts. The consensus was developed using three rounds of the Delphi technique. The first round developed a complete list of potential risk factors, the second round refined this list but also separated the factors into two population groups – active/athletic and inactive/sedentary. The third round ranked this list in order of perceived importance. Results Forty-four experts were invited to participate, 16 participated in the first round (response rate 40%) and two dropped out in the second round (resulting in a response rate of 35%). A total of 27 intrinsic and eight extrinsic risk factors were identified during round one. During round two only 12 intrinsic and five extrinsic risk factors were identified as important in active/athletic tendinopathy while 14 intrinsic and three extrinsic factors were identified as important for inactive/sedentary tendinopathy. Conclusions Risk factors for Achilles tendinopathy were identified based on expert consensus, and these factors provide a basis for primary epidemiological studies. Plantarflexor strength was identified as the primary modifiable factor in the active/athletic group while systemic factors were identified as important in the inactive/sedentary group, many of the potential factors suggested for either group were non-modifiable. Non-modifiable factors include: previous tendinopathy

  16. Treatment of Large Recurrent Bilateral Xanthomatosis of Achilles Tendon- A Case Report

    PubMed Central

    Senthil, L.; Jambu, N.; Chittaranjan, Samuel

    2015-01-01

    Introduction: Xanthomas of the Achilles tendon are a rare interesting orthopaedic condition. There are very few articles dealing with the treatment of recurrent xanthomatosis of tendoachilles. Here we report this patient with bilateral recurrent xanthomatosis of tendoachilles. Case Report: A 37 year old male patient presented with multiple lesions in the body with bilateral swelling in the tendoachilles. The swelling was excised before three years elsewhere and there was recurrence of the lesion after 6 months subsequently. There was ulceration on the right side. The patient was treated by total resection of the lesion and reconstruction using tensorfascialata graft. Conclusion: Complete excision of the lesion is needed to reduce recurrence. Reconstruction of the defect is a challenge due to the large defect. Tensorfascialata graft results in good functional outcome of the patient even in large defects. PMID:27299011

  17. The soy isoflavonegenistein inhibits the reduction in Achilles tendon collagen content induced byovariectomy in rats

    PubMed Central

    Ramos, Jahir E.; Al-Nakkash, Layla; Peterson, Amity; Gump, Brian S.; Janjulia, Tea; Moore, M. Scott; Broderick, Tom L.; Carroll, Chad C.

    2012-01-01

    The objective of this study was to evaluate effects of genistein and moderate intensity exercise on Achilles tendon collagen and cross-linking in intact and ovariectomized (OVX) female Sprague-Dawley rats. Rats were separated into eight groups (n=9 per group): intact or OVX, treadmill exercised or sedentary, genistein-treated (300 mg•kg−1•day−1) or vehicle. After 6-weeks, tendons were assayed for the collagen-specific amino acid hydroxyproline and hydroxylyslpyridinoline (HP). Collagen content was not influenced by exercise (p=0.40) but was lower (p<0.001) in OVX vehicle rats compared to intact vehicle rats (OVX: 894±35 µg collagen/mg dry weight, intact: 1185±72 µg collagen/mg dry weight). In contrast, collagen content in OVX rats treated with genistein was greater (p=0.010, 1198±121 µg collagen/mg dry weight) when compared to untreated rats and not different from intact rats (p=0.89). HP content was lower in OVX genistein-treated when compared to intact genistein-treated rats, but only within the sedentary animals (p=0.05, intact-treated: 232±39mmol/mol collagen, OVX-treated: 144±21mmol/mol collagen). Our findings suggest that ovariectomy leads to a reduction in tendon collagen, which is prevented by genistein. HP content, however, may not have increased in proportion to the addition of collagen. Genistein may be useful for improving tendon collagen content in conditions of estrogen deficiency. PMID:22852581

  18. Frequency characteristics of human muscle and cortical responses evoked by noisy Achilles tendon vibration.

    PubMed

    Mildren, Robyn Lynne; Peters, Ryan M; Hill, Aimee J; Blouin, Jean-Sebastien; Carpenter, Mark Gregory; Inglis, J Timothy

    2017-02-16

    Noisy stimuli, along with linear systems analysis, have proven to be effective for mapping functional neural connections. We explored the use of noisy (10-115 Hz) Achilles tendon vibration to examine proprioceptive reflexes in the triceps surae muscles in standing healthy young adults (n = 8). We also examined the association between noisy vibration and electrical activity recorded over the sensorimotor cortex using electroencephalography. We applied two-minutes of vibration and recorded ongoing muscle activity of the soleus and gastrocnemii using surface electromyography (EMG). Vibration amplitude was varied to characterize reflex scaling and to examine how different stimulus levels affected postural sway. Muscle activity from the soleus and gastrocnemii were significantly correlated with the tendon vibration across a broad frequency range (~10-80 Hz), with a peak located at ~40 Hz. Vibration-EMG coherence positively scaled with stimulus amplitude in all three muscles, with soleus displaying the strongest coupling and steepest scaling. EMG responses lagged the vibration by ~38 ms, a delay that paralleled observed response latencies to tendon taps. Vibration-evoked cortical oscillations were observed at frequencies ~40-70 Hz (peak ~54 Hz) in most subjects, a finding in line with previous reports of sensory evoked γ-band oscillations. Further examination of the method revealed a) accurate reflex estimates could be obtained with <60 s of low-level (RMS=10 m/s(2)) vibration, b) responses did not habituate over two-minutes of exposure, and importantly c) noisy vibration had a minimal influence on standing balance. Our findings suggest noisy tendon vibration is an effective novel approach to characterize proprioceptive reflexes.

  19. A comparative study of the effects of bromelain and fresh pineapple juice on the early phase of healing in acute crush achilles tendon injury.

    PubMed

    Aiyegbusi, Ayoola I; Olabiyi, Olaleye O; Duru, Francis I O; Noronha, Cressie C; Okanlawon, Abayomi O

    2011-04-01

    Bromelain, an enzyme extracted from the stem of the pineapple plant, has been reported to reduce pain and swelling in acute soft tissue injuries, but no study has been done to compare its effect with that of fresh pineapple juice on the healing of acute tendon injuries. This study compared the effects of commercial bromelain and fresh pineapple juice on tenocyte proliferation and the malondialdehyde (MDA) level in the early stage of healing in a crush injury to the Achilles tendon of Sprague-Dawley rats. Twenty-four male rats were divided randomly into three groups of eight rats each; all the rats had induced crush injury to the Achilles tendon: Group 1 (control), no treatment; Group 2, oral bromelain treatment at a dosage of 7 mg/kg of body weight daily; and Group 3, fresh diluted pineapple juice at a dosage of 30 mg/kg of body weight. Treatment was given over the first 14 days post-injury. On day 15 post-injury, the animals were sacrificed, and the tendons were excised and processed for histological study and MDA assay. Results show a significant difference in the tenocyte population between the bromelain group and the control (P < .05), whereas pineapple juice also increased the tenocyte population, although not significantly (P = .36). Pineapple juice, however, significantly lowered the MDA level compared with both the control and bromelain-treated groups. Based on this study, 600 GDU bromelain given at a dosage of 7 mg/kg had a better effect on tenocyte proliferation than fresh pineapple juice given once daily in acute tendon injury.

  20. Achilles tendon loading patterns during barefoot walking and slow running on a treadmill: An ultrasonic propagation study.

    PubMed

    Wulf, M; Wearing, S C; Hooper, S L; Smeathers, J E; Horstmann, T; Brauner, T

    2015-12-01

    Measurement of tendon loading patterns during gait is important for understanding the pathogenesis of tendon "overuse" injury. Given that the speed of propagation of ultrasound in tendon is proportional to the applied load, this study used a noninvasive ultrasonic transmission technique to measure axial ultrasonic velocity in the right Achilles tendon of 27 healthy adults (11 females and 16 males; age, 26 ± 9 years; height, 1.73 ± 0.07 m; weight, 70.6 ± 21.2 kg), walking at self-selected speed (1.1 ± 0.1 m/s), and running at fixed slow speed (2 m/s) on a treadmill. Synchronous measures of ankle kinematics, spatiotemporal gait parameters, and vertical ground reaction forces were simultaneously measured. Slow running was associated with significantly higher cadence, shorter step length, but greater range of ankle movement, higher magnitude and rate of vertical ground reaction force, and higher ultrasonic velocity in the tendon than walking (P < 0.05). Ultrasonic velocity in the Achilles tendon was highly reproducible during walking and slow running (mean within-subject coefficient of variation < 2%). Ultrasonic maxima (P1, P2) and minima (M1, M2) were significantly higher and occurred earlier in the gait cycle (P1, M1, and M2) during running than walking (P < 0.05). Slow running was associated with higher and earlier peaks in loading of the Achilles tendon than walking.

  1. Microcirculation in healing and healthy Achilles tendon assessed with invasive laser doppler flowmetry

    PubMed Central

    Arverud, Erica Domeij; Persson-Lindell, Olof; Sundquist, Fredrik; Labruto, Fausto; Edman, Gunnar; Ackermann, Paul W.

    2016-01-01

    Summary Introduction Achilles tendon (AT) rupture exhibits a prolonged healing process with varying clinical outcome. Reduced blood flow to the AT has been considered an underlying factor to AT rupture (ATR) and impaired healing. In vivo measurements using laser Doppler flowmetry (LDF) may be a viable method to assess blood flow in healthy and healing AT. Methods 29 persons were included in the study; 9 being ATR patients and 20 healthy subjects without any prior symptoms from the AT. Invasive LDF was used to determine the post-occlusive reactive hyperemia (PORH) in the paratenon after 15 minutes of occlusion of the lower extremities. ATR patients were examined two weeks post-operatively. Results LDF-assessments demonstrated a significantly different (p < 0.001) PORH response in the healing- versus intact- and control AT. In the healing AT, a slow, flattened PORH was observed compared to a fast, high peak PORH in intact, healthy AT. Conclusion in vivo LDF appears to be a feasible method to assess alterations in blood flow in healing and intact AT. The healing ATs capability to react to an ischemic period is clearly impaired, which may be due to the trauma at injury and/or surgery or degenerative changes in the tendon. PMID:27331035

  2. An Investigation of the Immediate Effect of Static Stretching on the Morphology and Stiffness of Achilles Tendon in Dominant and Non-Dominant Legs

    PubMed Central

    Chiu, Tsz-chun Roxy; Ngo, Hiu-ching; Lau, Lai-wa; Leung, King-wah; Lo, Man-him; Yu, Ho-fai; Ying, Michael

    2016-01-01

    Aims This study was undertaken to investigate the immediate effect of static stretching on normal Achilles tendon morphology and stiffness, and the different effect on dominant and non-dominant legs; and to evaluate inter-operator and intra-operator reliability of using shear-wave elastography in measuring Achilles tendon stiffness. Methods 20 healthy subjects (13 males, 7 females) were included in the study. Thickness, cross-sectional area and stiffness of Achilles tendons in both legs were measured before and after 5-min static stretching using grey-scale ultrasound and shear-wave elastography. Inter-operator and intra-operator reliability of tendon stiffness measurements of six operators were evaluated. Results Result showed that there was no significant change in the thickness and cross-sectional area of Achilles tendon after static stretching in both dominant and non-dominant legs (p > 0.05). Tendon stiffness showed a significant increase in non-dominant leg (p < 0.05) but not in dominant leg (p > 0.05). The inter-operator reliability of shear-wave elastography measurements was 0.749 and the intra-operator reliability ranged from 0.751 to 0.941. Conclusion Shear-wave elastography is a useful and non-invasive imaging tool to assess the immediate stiffness change of Achilles tendon in response to static stretching with high intra-operator and inter-operator reliability. PMID:27120097

  3. Running biomechanics in a long-term monitored recreational athlete with a history of Achilles tendon rupture.

    PubMed

    Jandacka, Daniel; Zahradnik, David; Foldyna, Karel; Hamill, Joseph

    2013-01-28

    This study represented a unique opportunity to understand changes in the human motion biomechanics during basic locomotion within a time interval of 4 years, when the monitored individual regained his original aerobic fitness, running performance and body mass index as prior to the injury. The participant visited the laboratory a month prior to the injury and during 4 years after the surgery. The surgery, subsequent rehabilitation and a 4-year running training programme in the studied recreational athlete did not completely eliminate the consequences of the Achilles tendon rupture. The function muscle deficit is namely manifested by a lower net plantar flexion moment and a lower net-generated ankle joint power during the take-off in the stance phase. The greater dorsal flexion in the affected ankle joint at the first contact with the ground and consequently higher peaks of ground reaction forces during running are consequences of the longer Achilles tendon in the affected lower extremity and weakened calf muscles.

  4. Both standing and postural threat decrease Achilles tendon reflex inhibition from tendon electrical stimulation.

    PubMed

    Horslen, Brian C; Inglis, J Timothy; Blouin, Jean-Sébastien; Carpenter, Mark G

    2017-03-22

    Golgi tendon organ Ib reflexes are thought to contribute to standing balance control, but it is unknown if they are modulated when people are exposed to a postural threat. We used a novel application of tendon electrical stimulation (TStim) to elicit Ib inhibitory reflexes in the medial gastrocnemius, while actively engaged in upright standing balance, to examine a) how Ib reflexes to TStim are influenced by upright stance, and b) the effects of height-induced postural threat on Ib reflexes during standing. TStim evoked short-latency (<47 ms) inhibition apparent in trigger-averaged rectified EMG, which was quantified in terms of area, duration, and mean amplitude of inhibition. In order to validate the use of TStim in a standing model, TStim-Ib inhibition was compared from conditions where participants were laying prone vs. standing upright. TStim evoked Ib inhibition in both conditions, however significant reductions in Ib inhibition area (42.2%) and duration (32.9%) were observed during stance. Postural threat, manipulated by having participants stand at LOW (0.8 m high, 0.6 m from edge) and HIGH (3.2 m, at edge) elevated surfaces, significantly reduced Ib inhibition area (32.4%), duration (16.4%) and amplitude (24.8%) in the HIGH, compared to LOW threat condition. These results demonstrate TStim is a viable technique for investigating Ib reflexes in standing, and confirm Ib reflexes are modulated with postural orientation. The novel observation of reduced Ib inhibition with elevated postural threat reveals that human Ib reflexes are context-dependent, and the human Ib reflex pathways are modulated by threat or emotional processing centres of the CNS. This article is protected by copyright. All rights reserved.

  5. [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.

  6. Achilles Tendinitis

    MedlinePlus

    ... will also evaluate the flexibility, alignment, range of motion and reflexes of your foot and ankle. Imaging ... real-time images of the Achilles tendon in motion, and color-Doppler ultrasound can evaluate blood flow ...

  7. Achilles Tendinitis

    MedlinePlus

    ... can cause the tendon to rupture (tear). Supportive shoes and orthotics. Pain from insertional Achilles tendinitis is o en helped by certain shoes, as well as orthotic devices. For example, shoes ...

  8. Operative Treatment of Haglund Syndrome With Central Achilles Tendon-Splitting Approach.

    PubMed

    Ahn, Jae Hoon; Ahn, Chi-Young; Byun, Chu-Hwan; Kim, Yoon-Chung

    2015-01-01

    Haglund syndrome is characterized by chronic posterior heel pain associated with a posterosuperior calcaneal prominence. We assessed the clinical and radiologic outcomes after operative treatment of Haglund syndrome using the central tendon-splitting approach. Fifteen feet in 15 patients were investigated retrospectively after surgery. Of the 15 patients, 14 were males (93.3%) and 1 was female (6.7%). Their mean age was 33.1 ± 8.2 (range 20 to 50) years. The mean follow-up duration was 3.5 ± 1.5 years (range 24 to 90 months). The American Orthopaedic Foot and Ankle Society ankle-hindfoot Scale and Victorian Institute of Sport Assessment-Achilles scores were investigated to assess the clinical outcomes. Patient satisfaction was assessed at the latest follow-up visit. The lateral talo-first metatarsal angle, calcaneal pitch angle, Fowler-Philip angle, and parallel pitch line were measured to assess the foot shape and radiographic outcomes. Clinically, the mean American Orthopaedic Foot and Ankle Society ankle-hindfoot scale score increased from 62.1 ± 7.5 preoperatively to 92.5 ± 3.5 at the latest follow-up visit. The mean Victorian Institute of Sport Assessment-Achilles score increased from 53.2 ± 7.4 to 89.6 ± 3.4. All patients were satisfied with the operative results. Radiographically, all patients had cavus feet with an increased lateral talo-first metatarsal angle (mean +5.9° ± 5.0°) and calcaneal pitch angle (mean 26.0° ± 3.8°). The mean Fowler-Philip angle decreased from 58.9° ± 15.0° to 32.5° ± 7.2° postoperatively, and the positive parallel pitch line had changed to a negative value in all cases. Operative treatment with the central tendon-splitting approach appears to be safe and satisfactory for intractable Haglund syndrome.

  9. Controlled release of curcumin from curcumin-loaded nanomicelles to prevent peritendinous adhesion during Achilles tendon healing in rats.

    PubMed

    Zhang, Weizhong; Li, Xuanyi; Comes Franchini, Mauro; Xu, Ke; Locatelli, Erica; Martin, Robert C; Monaco, Ilaria; Li, Yan; Cui, Shusen

    2016-01-01

    We introduced curcumin-loaded nanomicelles into a tendon-healing model to evaluate their effects on tendon healing and adhesion. Three groups consisting of 36 rats underwent rupture and repair of the Achilles tendon. The treatment group received an injection of curcumin-loaded nanomicelles (gold nanorods [GNRs]-1/curcumin in polymeric nanomicelles [curc@PMs] at a dosage of 0.44 mg curcumin/kg in 0.1 mL saline) into the surgical site and exposed to laser postoperatively at weeks 1, 2, and 3, for three times 10 seconds each, on the surgical site in the rats that underwent tendon rupture and repair, while the other two groups received 0.44 mg curcumin/kg in 0.1 mL saline and 0.1 mL of saline, respectively. The specimens were harvested at 4 weeks and subjected to biomechanical and histological evaluation. The scoring results of tendon adhesion indicated that GNRs-1/curc@PMs group was in the lowest grade of peritendinous adhesions compared to the other groups. Histological assessment further confirmed the preventive effect of GNRs-1/curc@PMs on tendon adhesion. These findings indicated greater tendon strength with less adhesion in the group treated with GNRs-1/curc@PMs combined with laser exposure, and that nanoparticle-based therapy may be applied to prevent adhesion in clinical patients.

  10. Controlled release of curcumin from curcumin-loaded nanomicelles to prevent peritendinous adhesion during Achilles tendon healing in rats

    PubMed Central

    Zhang, Weizhong; Li, Xuanyi; Comes Franchini, Mauro; Xu, Ke; Locatelli, Erica; Martin, Robert C; Monaco, Ilaria; Li, Yan; Cui, Shusen

    2016-01-01

    We introduced curcumin-loaded nanomicelles into a tendon-healing model to evaluate their effects on tendon healing and adhesion. Three groups consisting of 36 rats underwent rupture and repair of the Achilles tendon. The treatment group received an injection of curcumin-loaded nanomicelles (gold nanorods [GNRs]-1/curcumin in polymeric nanomicelles [curc@PMs] at a dosage of 0.44 mg curcumin/kg in 0.1 mL saline) into the surgical site and exposed to laser postoperatively at weeks 1, 2, and 3, for three times 10 seconds each, on the surgical site in the rats that underwent tendon rupture and repair, while the other two groups received 0.44 mg curcumin/kg in 0.1 mL saline and 0.1 mL of saline, respectively. The specimens were harvested at 4 weeks and subjected to biomechanical and histological evaluation. The scoring results of tendon adhesion indicated that GNRs-1/curc@PMs group was in the lowest grade of peritendinous adhesions compared to the other groups. Histological assessment further confirmed the preventive effect of GNRs-1/curc@PMs on tendon adhesion. These findings indicated greater tendon strength with less adhesion in the group treated with GNRs-1/curc@PMs combined with laser exposure, and that nanoparticle-based therapy may be applied to prevent adhesion in clinical patients. PMID:27382278

  11. Effect of Footwear Modifications on Oscillations at the Achilles Tendon during Running on a Treadmill and Over Ground: A Cross-Sectional Study

    PubMed Central

    Meinert, Ilka; Brown, Niklas; Alt, Wilfried

    2016-01-01

    Background Achilles tendon injuries are known to commonly occur in runners. During running repeated impacts are transferred in axial direction along the lower leg, therefore possibly affecting the oscillation behavior of the Achilles tendon. The purpose of the present study was to explore the effects of different footwear modifications and different ground conditions (over ground versus treadmill) on oscillations at the Achilles tendon. Methods Oscillations were measured in 20 male runners using two tri-axial accelerometers. Participants ran in three different shoe types on a treadmill and over ground. Data analysis was limited to stance phase and performed in time and frequency space. Statistical comparison was conducted between oscillations in vertical and horizontal direction, between running shoes and between ground conditions (treadmill versus over ground running). Results Differences in the oscillation behavior could be detected between measurement directions with peak accelerations in the vertical being lower than those in the horizontal direction, p < 0.01. Peak accelerations occurred earlier at the distal accelerometer than at the proximal one, p < 0.01. Average normalized power differed between running shoes (p < 0.01) with harder damping material resulting in higher power values. Little to no power attenuation was found between the two accelerometers. Oscillation behavior of the Achilles tendon is not influenced by ground condition. Conclusion Differences in shoe configurations may lead to variations in running technique and impact forces and therefore result in alterations of the vibration behavior at the Achilles tendon. The absence of power attenuation may have been caused by either a short distance between the two accelerometers or high stiffness of the tendon. High stiffness of the tendon will lead to complete transmission of the signal along the Achilles tendon and therefore no attenuation occurs. PMID:27010929

  12. UTE-T2⁎ Analysis of Diseased and Healthy Achilles Tendons and Correlation with Clinical Score: An In Vivo Preliminary Study

    PubMed Central

    Qiao, Yang; Tao, Hong-Yue; Ma, Kui; Wu, Zi-Ying; Qu, Jian-Xun

    2017-01-01

    Objective. To compare T2⁎ value of healthy and diseased Achilles tendons (AT) with a recently introduced three-dimensional ultrashort echo time (3D-UTE) sequence and analyze the correlation between T2⁎ value and clinical scores. Methods. Ten patients with symptomatic Achilles tendon and ten healthy volunteers were investigated with 3D-UTE sequence on a 3T magnetic resonance (MR) scanner. T2⁎ values of four regions in Achilles tendons were calculated. The clinical outcomes of patients were evaluated according to the American Orthopaedic Foot and Ankle Society (AOFAS) score and Achilles Tendon Rupture Score (ATRS). An independent sample t-test was used to compare the differences of T2⁎ value and clinical scores between two groups. The Pearson correlation coefficient between clinical scores and T2⁎ values was assessed. Results. The T2⁎ values of Achilles tendon were statistically significantly different between patients and volunteers. The Pearson correlation coefficients between T2⁎ and AOFAS or ATRS scores of patients were r = −0.733 and r = −0.634, respectively. Conclusion. The variability of T2⁎ in healthy and pathologic AT can be quantified by UTE-T2⁎. T2⁎ may be a promising marker to detect and diagnose AT tendinopathy. UTE-T2⁎ could give a precise guidance to clinical outcome. PMID:28154823

  13. UTE-T2(⁎) Analysis of Diseased and Healthy Achilles Tendons and Correlation with Clinical Score: An In Vivo Preliminary Study.

    PubMed

    Qiao, Yang; Tao, Hong-Yue; Ma, Kui; Wu, Zi-Ying; Qu, Jian-Xun; Chen, Shuang

    2017-01-01

    Objective. To compare T2(⁎) value of healthy and diseased Achilles tendons (AT) with a recently introduced three-dimensional ultrashort echo time (3D-UTE) sequence and analyze the correlation between T2(⁎) value and clinical scores. Methods. Ten patients with symptomatic Achilles tendon and ten healthy volunteers were investigated with 3D-UTE sequence on a 3T magnetic resonance (MR) scanner. T2(⁎) values of four regions in Achilles tendons were calculated. The clinical outcomes of patients were evaluated according to the American Orthopaedic Foot and Ankle Society (AOFAS) score and Achilles Tendon Rupture Score (ATRS). An independent sample t-test was used to compare the differences of T2(⁎) value and clinical scores between two groups. The Pearson correlation coefficient between clinical scores and T2(⁎) values was assessed. Results. The T2(⁎) values of Achilles tendon were statistically significantly different between patients and volunteers. The Pearson correlation coefficients between T2(⁎) and AOFAS or ATRS scores of patients were r = -0.733 and r = -0.634, respectively. Conclusion. The variability of T2(⁎) in healthy and pathologic AT can be quantified by UTE-T2(⁎). T2(⁎) may be a promising marker to detect and diagnose AT tendinopathy. UTE-T2(⁎) could give a precise guidance to clinical outcome.

  14. Achilles tendon material properties are greater in the jump leg of jumping athletes

    PubMed Central

    Bayliss, A.J.; Weatherholt, A.M.; Crandall, T.T.; Farmer, D.L.; McConnell, J.C.; Crossley, K.M.; Warden, S.J.

    2016-01-01

    Purpose: The Achilles tendon (AT) must adapt to meet changes in demands. This study explored AT adaptation by comparing properties within the jump and non-jump legs of jumping athletes. Non-jumping control athletes were included to control limb dominance effects. Methods: AT properties were assessed in the preferred (jump) and non-preferred (lead) jumping legs of male collegiate-level long and/or high jump (jumpers; n=10) and cross-country (controls; n=10) athletes. Cross-sectional area (CSA), elongation, and force during isometric contractions were used to estimate the morphological, mechanical and material properties of the ATs bilaterally. Results: Jumpers exposed their ATs to more force and stress than controls (all p≤0.03). AT force and stress were also greater in the jump leg of both jumpers and controls than in the lead leg (all p<0.05). Jumpers had 17.8% greater AT stiffness and 24.4% greater Young’s modulus in their jump leg compared to lead leg (all p<0.05). There were no jump versus lead leg differences in AT stiffness or Young’s modulus within controls (all p>0.05). Conclusion: ATs chronically exposed to elevated mechanical loading were found to exhibit greater mechanical (stiffness) and material (Young’s modulus) properties. PMID:27282454

  15. Achilles Tendon Reflex (ATR) in response to short exposures of microgravity and hypergravity

    NASA Technical Reports Server (NTRS)

    Fujii, M.; Jaweed, M.

    1992-01-01

    Previous studies indicate that latency and amplitude of the Achilles tendon reflex (ATR) are reduced after exposure to microgravity for 28 days. The objective of this study was to quantitatively measure the latency of ATR during brief (20 sec) exposure to microgravity in KC-135 parabolic flights. Methods: The ATR was elicited in ten men during parabolic flight with the ankle held neutrally, planarflexed, and dorsiflexed. During flight, the ATR was elicited during the zero G and 1.8 G phases. Postflight testing was performed flying back to the airfield. Latencies to onset of the ATR were calculated and analyses of variance were performed to determine the effect of gravity and ankle position on latency. Result: The mean latencies for zero-G, 1.8-G and postflight with the ankle in the neutral position were 32.7 plus or minus 0.5 ms, and 33.1 plus or minus 0.7 ms respectively, which were not significantly different. There was a trend toward prolongation of latencies postflight. The mean latency for those who were motion sick was 32.1 plus or minus 0.1 ms compared to 34.0 plus or minus 0.3 ms for those who were not sick. Conclusions: These studies indicate that neither the level of gravity nor ankle position significantly affected the latency of the ATR.

  16. Low-level laser therapy in IL-1β, COX-2, and PGE2 modulation in partially injured Achilles tendon.

    PubMed

    de Jesus, Julio Fernandes; Spadacci-Morena, Diva Denelle; dos Anjos Rabelo, Nayra Deise; Pinfildi, Carlos Eduardo; Fukuda, Thiago Yukio; Plapler, Helio

    2015-01-01

    This study evaluated IL-1β, COX-2, and PGE2 modulation in partially injured Achilles tendons treated with low-level laser therapy (LLLT). Sixty-five male Wistar rats were used. Sixty were submitted to a direct injury on Achilles tendon and then distributed into six groups: LASER 1 (a single LLLT application), LASER 3 (three LLLT applications), and LASER 7 (seven LLLT applications) and Sham 1, 3, and 7 (the same injury but LLLT applications were simulated). The five remaining animals were allocated at control group (no procedure performed). LLLT (780 nm) was applied with 70 mW of mean power and 17.5 J/cm(2) of fluency for 10 s, once a day. The tendons were surgically removed and assessed immunohistochemically for IL-1β, COX-2, and PGE2. In comparisons with control (IL-1β: 100.5 ± 92.5 / COX-2: 180.1 ± 97.1 / PGE2: 187.8 ± 128.8) IL-1β exhibited (mean ± SD) near-normal level (p > 0.05) at LASER 3 (142.0 ± 162.4). COX-2 and PGE2 exhibited near-normal levels (p > 0.05) at LASER 3 (COX-2: 176.9 ± 75.4 / PGE2: 297.2 ± 259.6) and LASER 7 (COX-2: 259.2 ± 190.4 / PGE2: 587.1 ± 409.7). LLLT decreased Achilles tendon's inflammatory process.

  17. Medium Term Follow-up of Achilles Tendon Lengthening in the Treatment of Ankle Equinus in Cerebral Palsy

    PubMed Central

    Dietz, Frederick R; Albright, Jay C; Dolan, Lori

    2006-01-01

    Introduction: The optimal treatment for equinus of the ankle in ambulatory patients with cerebral palsy is not known. This study assessed the medium term follow-up results of treatment of spastic ankle equinus deformity in cerebral palsy using Hoke or coronal Z-lengthening of the Achilles tendon. It was hypothesized that the use of Achilles tendon lengthening (TAL) as a treatment for spastic ankle equinus during gait results in a high rate of over-weakening of the triceps surae resulting in crouch gait. We also investigated patient characteristics that could identify which patients are at risk for crouch gait due to triceps surae weakening from Achilles tendon lengthening. Materials and Methods: Seventy-nine patients (114 procedures) who had undergone Achilles lengthening were retrospectively reviewed to determine how many patients developed crouch gait with dorsiflexion of the ankle throughout stance phase requiring anterior-floor-reaction bracing. The following patient characteristics were evaluated: age at surgery, geographic type of cerebral palsy, length of follow-up, need for anterior-floor-reaction bracing, length of time after surgery when brace was prescribed, age at time of need for bracing, side of surgery, technique used, additional procedures performed at time of TAL, previous or later procedures performed, and walking ability. Results: The average age at the time of TAL was 7 years and 3 months, and the average follow-up was seven years. The geographic type of cerebral palsy greatly affected the outcome. None of the twenty-three hemiplegic patients required bracing. Fourteen of 34 (41%) patients with spastic diplegia and seven of fourteen (50%) patients with spastic quadriplegia required bracing. There was no significant difference in outcome between the Hoke and the Z-lengthening procedures. Patients who underwent more procedures and bilateral procedures were more likely to require anterior-floor-reaction bracing. Conclusions: Achilles tendon

  18. Calf muscle atrophy and muscle function after non-operative vs operative treatment of achilles tendon ruptures.

    PubMed

    Häggmark, T; Liedberg, H; Eriksson, E; Wredmark, T

    1986-02-01

    Fifteen operatively and eight non-operatively treated subcutaneous achilles tendon ruptures were randomly selected from 120 surgically and 35 non-surgically treated patients. Their calf muscle function was studied three to five years after treatment. Non-operatively treated patients were found to have a significantly impaired dynamic muscle function of the calf muscles when tested in a specially constructed heel-raise test device. Operatively treated patients did not show any significant impairment of their muscle function. Measurement of muscle area with CT-scanning showed a significant reduction of the calf muscle in the non-operatively treated patient while no such difference could be found in the operatively treated patients. Isokinetic muscle torque did not differ in the two groups of patients, thus Cybex-measurements do not seem to be a discriminating method in studying muscle function after achilles ruptures. On the basis of our findings we recommend that all athletes with achilles tendon ruptures be treated surgically. In non-athletes and older patients non-operative treatment might be considered.

  19. Early weightbearing using Achilles suture bridge technique for insertional Achilles tendinosis: a review of 43 patients.

    PubMed

    Rigby, Ryan B; Cottom, James M; Vora, Anand

    2013-01-01

    Posterior heel pain caused by insertional Achilles tendinosis can necessitate surgical intervention when recalcitrant to conservative care. Surgical treatment can necessitate near complete detachment of the Achilles tendon to fully eradicate the offending pathologic features and, consequently, result in long periods of non-weightbearing. A suture bridge technique using bone anchors is available for reattachment of the Achilles tendon. This provides restoration of the Achilles footprint on the calcaneus, including not only contact, but also actual pressure between the tendon and bone. We performed a review of 43 patients who underwent surgical treatment of insertional Achilles tendinosis with reattachment of the Achilles tendon using the suture bridge technique. The mean age was 53 (range 29 to 87) years. The mean follow-up period was 24 (range 13 to 52) months. The mean postoperative American Orthopaedic Foot and Ankle Society score was 90 (range 65 to 100). The mean preoperative visual analog scale pain score was 6.8 (range 2 to 10) and the mean postoperative visual analog scale pain score was 1.3 (range 0 to 6). The mean interval to weightbearing was 10 (range 0 to 28) days. No postoperative ruptures occurred. Of the 43 patients, 42 (97.6%) successfully performed the single heel rise test at the final postoperative visit. Concomitant procedures were performed in 35 patients, including 33 (77%) requiring open gastrocnemius recession and 2 (5%) requiring flexor hallucis longus tendon transfer. A total of 42 patients (97.6%) returned to regular shoe gear, and 42 (97.6%) returned to their activities of daily living, including running for 20 athletic patients (100%). Complications included postoperative wound dehiscense requiring surgical debridement in 2 patients (5%) and soft tissue infection requiring antibiotics and surgical debridement in 1 (2%) patient. Our findings support using the Achilles tendon suture bridge for reattachment of the Achilles tendon in the

  20. [The echographic and clinical follow-up of patients operated on for subcutaneous rupture of the Achilles tendon].

    PubMed

    Cinotti, A; Massari, L; Traina, G C; Mannella, P

    1996-01-01

    Thanks to its good long-term results, surgery is the method of choice to treat subcutaneous ruptures of the Achilles tendon. Reconstructed tendons present typical morphological and functional US patterns which depend partly on the kind of surgical reconstruction and partly on the time passed since surgery. The authors report the results of the clinical and US follow-up of a series of 62 surgical patients treated in 7 years for the subcutaneous rupture of the Achilles tendon. The patients were 55 men and 7 women, whose mean age was 36 years (range: 25-65 years). The left-hand side was affected in 38 patients and the right-hand side in 24 patients. All patients were operated on using an end-to-end suture and reinforcement plastic surgery pulling down a gastrocnemius tendon flap. To homogenize the results, all the US exams were performed by the same operator, in the presence of the orthopedic specialist and under the same conditions: both the involved and the contralateral Achilles tendons were studied, longitudinal and transverse scans were performed with the foot in max. plantar and dorsal flexion and, whenever possible, dynamic scans were also performed making the sural triceps contract against resistance. The following parameters were studied clinically: pain (which was absent in 39 patients, occasional in 11, after stress in 9 and on walking in 3 patients), skin scar trophism (which was eutrophic in 53.23% of patients, keloid in 27.42% and hypertrophic in 19.35% of patients), ankle joint excursion (plantar flexion was impaired in 32.3% and dorsal flexion in 36% of patients), walking on tiptoe (in all, 22.6% of patients complained of difficulties walking on tiptoe) and, finally, work activity resumption (which all patients achieved). US depicted the surgical tendons as much bigger than the contralateral ones (3-4 times on the average), which increase in volume lasted throughout the follow-up. In 75% of patients the echo structure of the surgical tendons was

  1. Full symptomatic recovery does not ensure full recovery of muscle‐tendon function in patients with Achilles tendinopathy

    PubMed Central

    Silbernagel, Karin Grävare; Thomeé, Roland; Eriksson, Bengt I; Karlsson, Jon

    2007-01-01

    Objective To assess the relationship between muscle‐tendon function and symptoms in patients with Achilles tendinopathy using a validated test battery. Design A prospective non‐randomised trial. Setting Orthopaedic Department, Sahlgrenska University Hospital, Sweden. Patients 37 patients with a clinical diagnosis of Achilles tendinopathy in the midportion of the tendon, with symptoms for >2 months, were evaluated at the initiation of the study and after 1 year. Intervention The patients were treated using a rehabilitation programme, under the supervision of a physical therapist, for 6 months. Main outcome measurements The patients were evaluated using the Swedish version of the Victorian Institute of Sports Assessment—Achilles questionnaire (VISA‐A‐S) for symptoms, and a test battery for evaluation of the lower leg muscle‐tendon function. Results There were significant improvements in the VISA‐A‐S score (p<0.00, n = 37) and the test battery (p<0.02, n = 19) at the 1‐year follow‐up. The VISA‐A‐S questionnaire had an effect size of 2.1 and the test battery had an effect size of 0.73. A low correlation (r = 0.178, p>0.05) was found between the VISA‐A‐S score and the test battery. A high correlation (r = 0.611, p<0.05) was found between the drop counter movement jump and the VISA‐A‐S score. All other tests in the test battery had low correlations (r = −0.305 to 0.155, p>0.05) with the VISA‐A‐S score. Only 25% (4/16) of the patients who had full symptomatic recovery had achieved full recovery of muscle–tendon function as measured by the test battery. Conclusion Full symptomatic recovery in patients with Achilles tendinopathy does not ensure full recovery of muscle–tendon function. The VISA‐A‐S questionnaire and the test battery are sensitive to clinically relevant changes with treatment and can be recommended for use in both the clinic and research. PMID:17261555

  2. Knotless Repair of Achilles Tendon Rupture in an Elite Athlete: Return to Competition in 18 Weeks.

    PubMed

    Byrne, Paul A; Hopper, Graeme P; Wilson, William T; Mackay, Gordon M

    Rupture of the Achilles tendon is an increasingly common injury, particularly in physically active males, and current evidence favors minimally invasive surgical repair. We describe the case of a 36-year-old male elite bobsled athlete with complete rupture of the Achilles tendon. He was treated with surgical repair of the ruptured tendon using an innovative, minimally invasive procedure based on an internal bracing concept and was able to undergo early mobilization and aggressive physiotherapy rehabilitation. His recovery was such that he returned to training at 13 weeks postoperatively and participated in an international competition at 18 weeks, winning a World Cup silver medal. He subsequently raced at the 2014 Winter Olympic Games at 29 weeks after surgery. At >2 years since his injury, he has experienced no complications or reinjury. This represents an exceptional recovery that far exceeds the standard expected for such injuries. The use of this technique for athletes could enable accelerated return to sporting activity and attainment of their preinjury activity levels.

  3. Evaluation of the stiffnesses of the Achilles tendon and soleus from the apparent stiffness of the triceps surae.

    PubMed

    París-García, Federico; Barroso, Alberto; Doblaré, Manuel; Cañas, José; París, Federico

    2015-01-01

    The triceps surae plays an important role in the performance of many sports. Although the apparent average mechanical properties of the triceps surae may be a satisfactory parameter for estimating the training level of an athlete, a knowledge of the mechanical properties of the individual constituents of the triceps surae (in particular the Achilles tendon and soleus) permits a more detailed and in-depth control of the effects of training from more physically based parameters. The objective of this work is therefore the estimation of the individual viscoelastic properties (stiffness and viscosity) of soleus and Achilles tendon from the apparent properties of the triceps surae obtained by free vibration techniques. Different procedures have been developed and discussed, showing a high degree of robustness in the predictions. The results obtained for a non-oriented set of subjects present a high level of variability, depending on the training conditions and anthropometric features, although the corresponding average values compare well with data previously reported in the literature, particularly those associated with the tendon stiffness.

  4. Clinical and biomechanical outcome of minimal invasive and open repair of the Achilles tendon

    PubMed Central

    2011-01-01

    Introduction With evolutions in surgical techniques, minimally invasive surgical (MIS) repair with Achillon applicator has been introduced. However, there is still a lack of literature to investigate into the clinical merits of MIS over open surgery. This study aims to investigate the correlation between clinical outcome, gait analysis and biomechanical properties comparing both surgical methods. Materials and methods A single centre retrospective review on all the consecutive operated patients between January 2004 and December 2008 was performed. Twenty-six patients (19 male and 7 female; age 40.4 ± 9.2 years) had experienced a complete Achilles tendon rupture with operative repair. Nineteen of the patients, 10 MIS versus 9 open repairs (13 men with a mean age of 40.54 ± 10.43 (range 23-62 yrs) and 6 women with a mean age of 45.33 ± 7.71 (range 35-57 yrs) were further invited to attend a thorough clinical assessment using Holz's scale and biomechanical evaluation at a mean of 25.3 months after operation. This study utilized the Cybex II isokinetic dynamometer to assess the isokinetic peak force of plantar-flexion and dorsiflexion of both ankles. The patients were also invited to return to our Gait Laboratory for analysis. The eight-infrared camera motion capture system (VICON, UK) was utilized for the acquisition of kinematic variables. Their anthropometric data was measured according to the Davis and coworkers' standard. Results The mean operative time and length of hospital stay were shorter in the MIS group. The operative time was 54.55 ± 15.15 minutes versus 68.80 ± 18.23 minutes of the MIS group and Open group respectively (p = 0.045), whereas length of stay was 3.36 ± 1.21 days versus 6.40 ± 3.70 days respectively (p = 0.039). There is statistically significant decrease (p = 0.005) in incision length in MIS group than the open surgery group, 3.23 ± 1.10 cm versus 9.64 ± 2.55 cm respectively. Both groups attained similar Holz's scores, 11.70 ± 0

  5. Spectrum of Ultrasound Pathologies of Achilles Tendon, Plantar Aponeurosis and Flexor Digiti Brevis Tendon Heel Entheses in Patients with Clinically Suspected Enthesitis

    PubMed Central

    Sudoł-Szopińska, Iwona; Zaniewicz-Kaniewska, Katarzyna; Kwiatkowska, Brygida

    2014-01-01

    Summary Background Enthesitis is considered a characteristic presentation of the second most common group of rheumatoid disorders, i.e. spondyloarthropathies (SpAs), particularly peripheral spondyloarthropathies. At the initial stages, enthesitis may be the only symptom of SpA, particularly in patients lacking the HLA-B27 receptor. Material/Methods In light of diagnostic difficulties with detecting enthesitis in clinical examinations and laboratory investigations, many studies point out the high specificity of imaging studies, and particularly ultrasonography. Results A total of 20% Achilles tendon entheses, 45% plantar aponeurosis entheses and 89.5% of flexor digiti brevis tendon entheses were unremarkable. In the remaining cases, the presentation of pathological lesions was not specific to enthesitis and might more likely correspond to degeneration or microinjuries of the entheses, beside the most obvious cases of achillobursitis or Kager’s fat pad inflammation. Conclusions The studies demonstrated that ultrasound scans rarely confirm the clinical diagnosis of enthesitis. PMID:25674194

  6. The Utility of Clinical Measures for the Diagnosis of Achilles Tendon Injuries: A Systematic Review With Meta-Analysis

    PubMed Central

    Reiman, Michael; Burgi, Ciara; Strube, Eileen; Prue, Kevin; Ray, Keaton; Elliott, Amanda; Goode, Adam

    2014-01-01

    Objective: To summarize and evaluate the current diagnostic accuracy of clinical measures used to diagnose Achilles tendon injuries. Data Sources: A literature search of MEDLINE, CINAHL, and EMBASE databases was conducted with key words related to diagnostic accuracy and Achilles tendon injuries. Study Selection: Original research articles investigating Achilles tendon injuries against an acceptable reference standard were included. Data Extraction: Three studies met the inclusion criteria. Quality assessment was conducted using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. DerSimonian-Laird random-effects models were used to pool sensitivity (SN), specificity (SP), and diagnostic odds ratios with their 95% confidence intervals (CIs). Data Synthesis: The SN and negative likelihood ratio (−LR) values for Achilles tendon rupture measures ranged from 0.73 (95% CI = 0.65, 0.81) and 0.30 (95% CI = 0.23, 0.40) to 0.96 (95% CI = 0.93, 0.99) and 0.04 (95% CI = 0.02, 0.10), respectively, whereas SP and positive likelihood ratio (+LR) values ranged from 0.85 (95% CI = 0.72, 0.98) and 6.29 (95% CI = 2.33, 19.96) to 0.93 (95% CI = 0.84, 1.00) and 13.71 (95% CI = 3.54, 51.24), respectively, with the highest SN and SP both reported in the calf-squeeze test. The SN and −LR values for Achilles tendinopathy measures ranged from 0.03 (95% CI = 0.00, 0.08) and 0.97 (95% CI = not reported) to 0.89 (95% CI = 0.75, 0.98) and 0.19 (95% CI = not reported), whereas SP and +LR values ranged from 0.58 (95% CI = 0.38, 0.77) and 2.12 (95% CI = not reported) to 1.00 (95% CI = 1.00, 1.00) and infinity, respectively, with the highest SN and SP reported for morning stiffness and palpation for crepitus. Pooled analyses demonstrated similar diagnostic properties in all 3 clinical measures (arc sign, palpation, and Royal London Hospital test), with SN and −LR ranging from 0.42 (95% CI = 0.23, 0.62) and 0.68 (95% CI = 0.50, 0.93), respectively, for the arc sign, to 0.64 (95% CI

  7. Achilles tendon stress is more sensitive to subject-specific geometry than subject-specific material properties: A finite element analysis.

    PubMed

    Hansen, Wencke; Shim, Vickie B; Obst, Steven; Lloyd, David G; Newsham-West, Richard; Barrett, Rod S

    2017-03-04

    This study used subject-specific measures of three-dimensional (3D) free Achilles tendon geometry in conjunction with a finite element method to investigate the effect of variation in subject-specific geometry and subject-specific material properties on tendon stress during submaximal isometric loading. Achilles tendons of eight participants (Aged 25-35years) were scanned with freehand 3D ultrasound at rest and during a 70% maximum voluntary isometric contraction. Ultrasound images were segmented, volume rendered and transformed into subject-specific 3D finite element meshes. The mean (±SD) lengths, volumes and cross-sectional areas of the tendons at rest were 62±13mm, 3617±984mm(3) and 58±11mm(2) respectively. The measured tendon strain at 70% MVIC was 5.9±1.3%. Subject-specific material properties were obtained using an optimisation approach that minimised the difference between measured and modelled longitudinal free tendon strain. Generic geometry was represented by the average mesh and generic material properties were taken from the literature. Local stresses were subsequently computed for combinations of subject-specific and generic geometry and material properties. For a given geometry, changing from generic to subject-specific material properties had little effect on the stress distribution in the tendon. In contrast, changing from generic to subject-specific geometry had a 26-fold greater effect on tendon stress distribution. Overall, these findings indicate that the stress distribution experienced by the living free Achilles tendon of a young and healthy population during voluntary loading are more sensitive to variation in tendon geometry than variation in tendon material properties.

  8. Running biomechanics in a long-term monitored recreational athlete with a history of Achilles tendon rupture

    PubMed Central

    Jandacka, Daniel; Zahradnik, David; Foldyna, Karel; Hamill, Joseph

    2013-01-01

    This study represented a unique opportunity to understand changes in the human motion biomechanics during basic locomotion within a time interval of 4 years, when the monitored individual regained his original aerobic fitness, running performance and body mass index as prior to the injury. The participant visited the laboratory a month prior to the injury and during 4 years after the surgery. The surgery, subsequent rehabilitation and a 4-year running training programme in the studied recreational athlete did not completely eliminate the consequences of the Achilles tendon rupture. The function muscle deficit is namely manifested by a lower net plantar flexion moment and a lower net-generated ankle joint power during the take-off in the stance phase. The greater dorsal flexion in the affected ankle joint at the first contact with the ground and consequently higher peaks of ground reaction forces during running are consequences of the longer Achilles tendon in the affected lower extremity and weakened calf muscles. PMID:23362072

  9. Radial shock waves effectively introduced NF-kappa B decoy into rat achilles tendon cells in vitro.

    PubMed

    Sugioka, Kaori; Nakagawa, Koichi; Murata, Ryo; Ochiai, Nobuyasu; Sasho, Takahisa; Arai, Momoko; Tsuruoka, Hiroaki; Ohtori, Seiji; Saisu, Takashi; Gemba, Takefumi; Takahashi, Kazuhisa

    2010-08-01

    The purpose of this study was to test if radial shock waves could enhance the introduction of nuclear factor-kappa B (NF-kappaB) decoy oligodeoxynucleotides, which is reported to markedly inhibit NF-kappaB activation and suppress pro-inflammatory cytokine gene expression, using rat Achilles tendon cells. In the presence of NF-kappaB decoy labeled with or without fluorescein isothiocyanate (FITC) in culture media, radial shock waves were applied to the tendon cells in variable conditions and cultivated for 24 h. The transfection rate was assessed by counting FITC-positive cells, and IL-1-induced NF-kappaB activation in the cells was assessed. Radial shock waves significantly enhanced introduction of NF-kappaB decoy-FITC into the tendon cells. IL-1-induced NF-kappaB activation was significantly inhibited by pretreatment of the cells with NF-kappaB decoy combined with radial shock wave exposure. The present study demonstrated the effectiveness of radial shock waves on introduction of NF-kappaB decoy into tendon cells. Radial shock wave treatment combined with local NF-kappaB decoy administration could be a novel therapeutic strategy for chronic tendinopathy.

  10. In vivo quantification of the shear modulus of the human Achilles tendon during passive loading using shear wave dispersion analysis

    NASA Astrophysics Data System (ADS)

    Helfenstein-Didier, C.; Andrade, R. J.; Brum, J.; Hug, F.; Tanter, M.; Nordez, A.; Gennisson, J.-L.

    2016-03-01

    The shear wave velocity dispersion was analyzed in the Achilles tendon (AT) during passive dorsiflexion using a phase velocity method in order to obtain the tendon shear modulus (C 55). Based on this analysis, the aims of the present study were (i) to assess the reproducibility of the shear modulus for different ankle angles, (ii) to assess the effect of the probe locations, and (iii) to compare results with elasticity values obtained with the supersonic shear imaging (SSI) technique. The AT shear modulus (C 55) consistently increased with the ankle dorsiflexion (N  =  10, p  <  0.05). Furthermore, the technique showed a very good reproducibility (all standard error of the mean values  <10.7 kPa and all coefficient of variation (CV) values  ⩽0.05%). In addition, independently from the ankle dorsiflexion, the shear modulus was significantly higher in the proximal location compared to the more distal one. The shear modulus provided by SSI was always lower than C55 and the difference increased with the ankle dorsiflexion. However, shear modulus values provided by both methods were highly correlated (R  =  0.84), indicating that the conventional shear wave elastography technique (SSI technique) can be used to compare tendon mechanical properties across populations. Future studies should determine the clinical relevance of the shear wave dispersion analysis, for instance in the case of tendinopathy or tendon tear.

  11. Differential strain patterns of the human Achilles tendon determined in vivo with freehand three-dimensional ultrasound imaging.

    PubMed

    Farris, Dominic James; Trewartha, Grant; McGuigan, M Polly; Lichtwark, Glen A

    2013-02-15

    The human Achilles tendon (AT) has often been considered to act as a single elastic structure in series with the muscles of the triceps surae. As such it has been commonly modelled as a Hookean spring of uniform stiffness. However, the free AT and the proximal AT have distinctly different structures that lend themselves to different elastic properties. This study aimed to use three-dimensional freehand ultrasound imaging to determine whether the proximal AT and the free AT exhibit different elastic behaviour during sub-maximal, fixed-end contractions of the triceps surae. Six male and five female participants (mean ± s.d. age=27 ± 5 years) performed fixed position contractions of the plantar-flexors on an isokinetic dynamometer at 50% of their maximum voluntary contraction in this position. Freehand three-dimensional ultrasound imaging was used to reconstruct the free-tendon and proximal AT at rest and during contraction. The free-tendon exhibited significantly (P=0.03) greater longitudinal strain (5.2 ± 1.7%) than the proximal AT (2.6 ± 2.0%). The lesser longitudinal strain of the proximal AT was linked to the fact that it exhibited considerable transverse (orthogonal to the longitudinal direction) strains (5.0 ± 4%). The transverse strain of the proximal AT is likely due to the triceps surae muscles bulging upon contraction, and thus the level of bulging may influence the elastic behaviour of the proximal AT. This might have implications for the understanding of triceps surae muscle-tendon interaction during locomotion, tendon injury mechanics and previous measurements of AT elastic properties.

  12. Three-Dimensional Gait Analysis Following Achilles Tendon Rupture With Nonsurgical Treatment Reveals Long-Term Deficiencies in Muscle Strength and Function

    PubMed Central

    Tengman, Tine; Riad, Jacques

    2013-01-01

    Background: Precise long-term assessment of movement and physical function following Achilles tendon rupture is required for the development and evaluation of treatment, including different regimens of physical therapy. Purpose: To assess intermediate-term (<10 years by conventional thinking) objective measures of physical function following Achilles tendon rupture treated nonsurgically and to compare these with self-reported measures of physical function. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Two to 5 years after Achilles tendon rupture, 9 women and 43 men (mean age, 49.2 years; range, 26-68 years) were assessed by physical examination, performance of 1-legged jumps, and 3-dimensional gait analysis (including calculation of muscle work). Self-reported scores for foot function (Achilles tendon rupture score) and level of physical activity were collected. Twenty age- and sex-matched controls were assessed in the same manner. Results: Physical examination of patients with the knee extended revealed 11.1° of dorsiflexion on the injured side and 9.2° on the uninjured side (P = .020), indicating gastrocnemius muscle lengthening. The 1-legged jump distance was shorter on the injured side (89.5 vs 96.2 cm; P < .001). Gait analysis showed higher peak dorsiflexion (14.3° vs 13.3°; P = .016) and lower concentric (positive) plantar flexor work (16.6 vs 19.9 J/kg; P = .001) in the ankle on the uninjured side. At the same time, eccentric (negative) dorsiflexor work was higher on the injured side (13.2 vs 11.9 J/kg; P = .010). Self-perceived foot function and physical activity were lower in patients than in healthy controls (mean Achilles tendon rupture score, 78.6 and 99.8, respectively). Conclusion: Nonsurgically treated patients with Achilles tendon rupture showed signs of both anatomic and functional lengthening of the tendon. Attenuated muscle strength and function were present during walking as long as 2 to 5 years after rupture, as

  13. Multilayered Electrospun Scaffolds for Tendon Tissue Engineering

    PubMed Central

    Chainani, Abby; Hippensteel, Kirk J.; Kishan, Alysha; Garrigues, N. William; Ruch, David S.; Guilak, Farshid

    2013-01-01

    Full-thickness rotator cuff tears are one of the most common causes of shoulder pain in people over the age of 65. High retear rates and poor functional outcomes are common after surgical repair, and currently available extracellular matrix scaffold patches have limited abilities to enhance new tendon formation. In this regard, tissue-engineered scaffolds may provide a means to improve repair of rotator cuff tears. Electrospinning provides a versatile method for creating nanofibrous scaffolds with controlled architectures, but several challenges remain in its application to tissue engineering, such as cell infiltration through the full thickness of the scaffold as well as control of cell growth and differentiation. Previous studies have shown that ligament-derived extracellular matrix may enhance differentiation toward a tendon or ligament phenotype by human adipose stem cells (hASCs). In this study, we investigated the use of tendon-derived extracellular matrix (TDM)-coated electrospun multilayered scaffolds compared to fibronectin (FN) or phosphate-buffered saline (PBS) coating for use in rotator cuff tendon tissue engineering. Multilayered poly(ɛ-caprolactone) scaffolds were prepared by sequentially collecting electrospun layers onto the surface of a grounded saline solution into a single scaffold. Scaffolds were then coated with TDM, FN, or PBS and seeded with hASCs. Scaffolds were maintained without exogenous growth factors for 28 days in culture and evaluated for protein content (by immunofluorescence and biochemical assay), markers of tendon differentiation, and tensile mechanical properties. The collagen content was greatest by day 28 in TDM-scaffolds. Gene expression of type I collagen, decorin, and tenascin C increased over time, with no effect of scaffold coating. Sulfated glycosaminoglycan and dsDNA contents increased over time in culture, but there was no effect of scaffold coating. The Young's modulus did not change over time, but yield strain

  14. Power Doppler ultrasonography of painful Achilles tendons and entheses in patients with and without spondyloarthropathy: a comparison with clinical examination and contrast-enhanced MRI.

    PubMed

    Wiell, Charlotte; Szkudlarek, Marcin; Hasselquist, Maria; Møller, Jakob M; Nørregaard, Jesper; Terslev, Lene; Ostergaard, Mikkel

    2013-03-01

    The objective of this study was to describe ultrasonography (US) and magnetic resonance imaging (MRI) findings at painful Achilles tendons and entheses in patients with and without spondyloarthropathy (SpA and non-SpA) and healthy control persons (CTRLs). Particularly, we aimed to investigate if any changes differentiate SpA from non-SpA. Finally, we investigated the reliability of US compared to clinical examination of Achilles tendinopathy, using MRI as gold standard reference. Twelve SpA patients and 15 non-SpA patients with pain and tenderness at at least one Achilles tendon and/or enthesis due to sports-related causes and 10 CTRLs were examined at the Achilles tendons and entheses with US, MRI and clinical assessment. Intratendinous changes, entheseal changes, bursitis and peritendonitis were assessed. An US interobserver substudy was performed in nine persons. US findings showed high agreement between observers (median 89 %, κ = 0.64) and with MRI (median 89 %, κ = 0.74). All inflammatory intratendinous changes were less frequent in SpA than non-SpA patients (p < 0.05). Entheseal changes and bursitis were found equally frequent in both patient groups except for enthesophytes, which were most common in the SpA group (p < 0.01). No findings were exclusively found in SpA. When MRI was considered gold standard, US showed higher sensitivity for intratendinous and entheseal changes than clinical examination (median sensitivity 0.83 versus 0.66). Especially, entheseal changes had higher sensitivity than clinical examination without loss of specificity. In conclusion, US performed by a trained operator can be a useful adjunct to clinical examination for improved assessment of Achilles tendons and entheses.

  15. Green Tea and Glycine Modulate the Activity of Metalloproteinases and Collagen in the Tendinitis of the Myotendinous Junction of the Achilles Tendon.

    PubMed

    Vieira, Cristiano Pedrozo; De Oliveira, LetÍCia Prado; Da Ré Guerra, Flávia; Marcondes, Maria Cristina Cintra; Pimentel, Edson Rosa

    2016-07-01

    The myotendinous junction (MTJ) is the weakest element in the muscle-tendon unit of the heel, and thus the most susceptible to injuries. The scarcity of adequate treatments means that tendinitis is a major concern to athletes and other groups who depend on their physical fitness, although green tea and glycine have both been shown to have beneficial effects on the inflammation. The present study investigated the remodeling effects of green tea and glycine in the MTJ of rats with tendinitis. For this, male Wistar rats were divided into five groups: animals without tendinitis and animals with tendinitis; animals with tendinitis supplied with green tea; animals with tendinitis supplied with a glycine diet; animals with tendinitis supplied with a green tea and glycine diet. Tendinitis was induced and the treatment with green tea (700 mg/kg/day) and a 5% glycine diet lasted 7 days. The treatments regulated the activity of metalloproteinases (MMP)-2, -8, and -9, and induced the synthesis of type I collagen, glycosaminoglycans, and non-collagenous proteins. Changes were also noted in the compaction of the collagen molecules and the amount of tenocytes. When combined, green tea and glycine modulated the inflammatory process and induced the synthesis of the elements involved in the post-lesion recovery of the tissue. The data from the MTJ were different when compared with results already published using the whole Achilles tendon. These data indicate that each region of the inflamed tendon can exhibit different responses during the treatment and therefore, modify its extracellular matrix components to facilitate recovery and repair. Anat Rec, 299:918-928, 2016. © 2016 Wiley Periodicals, Inc.

  16. [Reconstruction of a chronic Achilles tendon lesion with autologous peroneus brevis graft].

    PubMed

    Estrada-Malacón, Ciro Arturo; García-Estrada, Gustavo Adolfo

    2009-01-01

    The calcaneal tendon lesion is very important due to the role of this tendon on gait performance, therefore a treatment strategy allowing the patient to resume activities of daily living as soon as possible is of the utmost importance. Treatment with a surgical approach involving the lateral peroneus brevis tendon facilitates bipodal support and immediate rehabilitation allowing the patient to resume activities of daily living as soon as possible.

  17. The soy isoflavone genistein inhibits the reduction in Achilles tendon collagen content induced by ovariectomy in rats.

    PubMed

    Ramos, J E; Al-Nakkash, L; Peterson, A; Gump, B S; Janjulia, T; Moore, M S; Broderick, T L; Carroll, C C

    2012-10-01

    The objective of this study was to evaluate the effects of genistein and moderate intensity exercise on Achilles tendon collagen and cross-linking in intact and ovariectomized (OVX) female Sprague-Dawley rats. Rats were separated into eight groups (n = 9/group): intact or OVX, treadmill exercised or sedentary, genistein-treated (300 mg/kg/day) or vehicle. After 6 weeks, tendons were assayed for the collagen-specific amino acid hydroxyproline and hydroxylyslpyridinoline (HP). Collagen content was not influenced by exercise (P = 0.40) but was lower (P < 0.001) in OVX-vehicle rats compared with intact vehicle rats (OVX: 894 ± 35 μg collagen/mg dry weight; intact: 1185 ± 72 μg collagen/mg dry weight). In contrast, collagen content in OVX rats treated with genistein was greater (P = 0.010, 1198 ± 121 μg collagen/mg dry weight) when compared with untreated rats and was not different from intact rats (P = 0.89). HP content was lower in OVX genistein-treated rats when compared with intact genistein-treated rats, but only within the sedentary animals (P = 0.05, intact-treated: 232 ± 39 mmol/mol collagen; OVX-treated: 144 ± 21 mmol/mol collagen). Our findings suggest that ovariectomy leads to a reduction in tendon collagen, which is prevented by genistein. HP content, however, may not have increased in proportion to the addition of collagen. Genistein may be useful for improving tendon collagen content in conditions of estrogen deficiency.

  18. Subject-specific measures of Achilles tendon moment arm using ultrasound and video-based motion capture

    PubMed Central

    Manal, Kurt; Cowder, Justin D; Buchanan, Thomas S

    2013-01-01

    The Achilles tendon (AT) moment arm is an important biomechanical parameter most commonly estimated using one of two methods: (A) center of rotation and (B) tendon excursion. Conflicting findings regarding magnitude and whether it changes with contraction intensity have been reported when using these methods. In this study, we present an alternate method of measuring the AT moment arm by combining ultrasound and video-based motion capture. Moment arms for 10 healthy male subjects were measured at five different joint angles in 10° increments ranging from 20° of dorsiflexion (DF) to 20° of plantar flexion (PF). Moment arms were measured at rest and also during maximum voluntary contraction (MVC). For both conditions, the AT moment arm increased in magnitude as the ankle moved from DF to PF. In 20° of DF, the moment arm at rest averaged 34.6 ± 1.8 mm and increased to a maximum value of 36.9 ± 1.9 mm when plantar flexed to 10°. Moment arms during MVC ranged from 35.7 ± 1.8 mm to 38.1 ± 2.6 mm. The moment arms we obtained were much more consistent with literature values derived using ultrasound and tendon excursion compared to center of rotation or in vitro methods. This is noteworthy as the hybrid method is easy to implement and as it is less costly and timing consuming than other methods, including tendon excursion, it is well suited for large-scale studies involving many subjects. PMID:24400141

  19. Age-related greater Achilles tendon compliance is not associated with larger plantar flexor muscle fascicle strains in senior women

    PubMed Central

    Csapo, R.; Malis, V.; Hodgson, J.

    2014-01-01

    The aim of the present study was to test the hypothesis that the age-associated decrease of tendon stiffness would necessitate greater muscle fascicle strains to produce similar levels of force during isometric contraction. Greater fascicle strains could force sarcomeres to operate in less advantageous regions of their force-length and force-velocity relationships, thus impairing the capacity to generate strong and explosive contractions. To test this hypothesis, sagittal-plane dynamic velocity-encoded phase-contrast magnetic resonance images of the gastrocnemius medialis (GM) muscle and Achilles tendon (AT) were acquired in six young (YW; 26.1 ± 2.3 yr) and six senior (SW; 76.7 ± 8.3 yr) women during submaximal isometric contraction (35% maximum voluntary isometric contraction) of the plantar flexor muscles. Multiple GM fascicle lengths were continuously determined by automatically tracking regions of interest coinciding with the end points of muscle fascicles evenly distributed along the muscle's proximo-distal length. AT stiffness and Young's modulus were measured as the slopes of the tendon's force-elongation and stress-strain curves, respectively. Despite significantly lower AT stiffness at older age (YW: 120.2 ± 52.3 N/mm vs. SW: 53.9 ± 44.4 N/mm, P = 0.040), contraction-induced changes in GM fascicle lengths were similar in both age groups at equal levels of absolute muscular force (4–5% fascicle shortening in both groups), and even significantly larger in YW (YW: 11–12% vs. SW: 6–8% fascicle shortening) at equal percentage of maximum voluntary contraction. These results suggest that factors other than AT stiffness, such as age-associated changes in muscle composition or fascicle slack, might serve as compensatory adaptations, limiting the degree of fascicle strains upon contraction. PMID:24505104

  20. Structural and biomechanical changes in the Achilles tendon after chronic treatment with statins.

    PubMed

    de Oliveira, L P; Vieira, C P; Guerra, F D; Almeida, M S; Pimentel, E R

    2015-03-01

    Cases of tendinopathy and tendon ruptures have been reported as side effects associated with statin therapy. This work assessed possible changes in the structural and biomechanical properties of the tendons after chronic treatment with statins. Wistar rats were divided into the following groups: treated with atorvastatin (A-20 and A-80), simvastatin (S-20 and S-80) and the group that received no treatment (C). The doses of statins were calculated using allometric scaling, based on the doses of 80 mg/day and 20 mg/day recommended for humans. The morphological aspect of the tendons in A-20, S-20 and S-80 presented signals consistent with degeneration. Both the groups A-80 and S-80 showed a less pronounced metachromasia in the compression region of the tendons. Measurements of birefringence showed that A-20, A-80 and S-80 groups had a lower degree of organization of the collagen fibers. In all of the groups treated with statins, the thickness of the epitenon was thinner when compared to the C group. In the biomechanical tests the tendons of the groups A-20, A-80 and S-20 were less resistant to rupture. Therefore, statins affected the organization of the collagen fibers and decreased the biomechanical strength of the tendons, making them more predisposed to ruptures.

  1. Staged tendon grafts and soft tissue coverage.

    PubMed

    Elliot, David

    2011-05-01

    The objective of the two-staged flexor tendon method is to improve the predictability of final results in difficult problems dealing with tendon reconstruction. This article reviews the evolution and benefits of this procedure. It also considers the use of the technique to help deal with problems requiring pulley and skin reconstruction simultaneously with re-constituting the flexor tendon system.

  2. Tunnel widening prevention with the allo-Achilles tendon graft in anterior cruciate ligament reconstruction: Surgical tips and short term followup

    PubMed Central

    Suh, Dong Won; Han, Seung Beom; Yeo, Woo Jin; Lee, Won Hee; Kwon, Jae Ho; Kyung, Bong Soo

    2017-01-01

    Background: Tunnel widening (TW) after anterior cruciate ligament (ACL) reconstruction can be a serious complication, and there is controversy over how to prevent it. This study aimed to suggest surgical approaches to prevent TW using an allo-Achilles tendon graft, and then to evaluate TW after these surgical tips were applied. Materials and Methods: Sixty two patients underwent ACL reconstruction with an allo-Achilles tendon graft. Four surgical approaches were used: Making a tibial tunnel by bone impaction, intraarticular reamer application, bone portion application for the femoral tunnel, and an additional bone plug application for the tibial tunnel. After more than 1-year, followup radiographs including anteroposterior and lateral views were taken in 29 patients encompassing thirty knees. The diameter of the tunnels at postoperation day 1 (POD1) and at followup was measured and compared. Results: In 18 knees (60%), there were no visible femoral tunnel margins on the radiographs at POD1 or followup. In the other 12 cases, which had visible femoral tunnel margins on followup radiographs, the mean femoral tunnel diameter was 8.6 mm. In the tibial tunnel, the mean diameters did not increase on all three levels (proximal, middle, and distal), and there was no statistically significant difference between the diameters at POD1 and followup. Conclusion: The suggested tips for surgery involving an allo-Achilles tendon graft can effectively prevent TW after ACL reconstruction according to this case series. These surgical tips can prevent TW.

  3. Influence of intramuscular fiber orientation on the Achilles tendon curvature using three-dimensional finite element modeling of contracting skeletal muscle.

    PubMed

    Kinugasa, Ryuta; Yamamura, Naoto; Sinha, Shantanu; Takagi, Shu

    2016-10-03

    Tendon curvature plays a key role in mechanical gain (amplifying the joint excursion relative to fiber length change) during joint motion, but the mechanism remains unresolved. A three-dimensional finite element (FE) model was used to investigate the influence of intramuscular fiber orientation upon the curvature pattern of the Achilles tendon during active muscular contraction. Two simulation models, with fiber pennation angles of θ = 25° and 47° were tested for the gastrocnemius and soleus muscles. A smaller pennation angle (25°) of the soleus muscle fibers was accompanied by a large change in curvature whereas a larger pennation angle (47°) of the soleus muscle was accompanied by small effects. These results suggest that the fiber pennation angle determines the curvature of the tendon, and the magnitude of the curvature varies along the length of the aponeurosis. Such FE modeling has the potential of determining changes in force output consequent to changes in intramuscular fiber orientation arising from resistance training or unloading, and provides mechanism for predicting the risk of Achilles tendon ruptures.

  4. Regular physical activity reduces the effects of Achilles tendon vibration on postural control for older women.

    PubMed

    Maitre, J; Serres, I; Lhuisset, L; Bois, J; Gasnier, Y; Paillard, T

    2015-02-01

    The aim was to determine in what extent physical activity influences postural control when visual, vestibular, and/or proprioceptive systems are disrupted. Two groups of healthy older women: an active group (74.0 ± 3.8 years) who practiced physical activities and a sedentary group (74.7 ± 6.3 years) who did not, underwent 12 postural conditions consisted in altering information emanating from sensory systems by means of sensory manipulations (i.e., eyes closed, cervical collar, tendon vibration, electromyostimulation, galvanic vestibular stimulation, foam surface). The center of foot pressure velocity was recorded on a force platform. Results indicate that the sensory manipulations altered postural control. The sedentary group was more disturbed than the active group by the use of tendon vibration. There was no clear difference between the two groups in the other conditions. This study suggests that the practice of physical activities is beneficial as a means of limiting the effects of tendon vibration on postural control through a better use of the not manipulated sensory systems and/or a more efficient reweighting to proprioceptive information from regions unaffected by the tendon vibration.

  5. Mechanical characteristics of native tendon slices for tissue engineering scaffold

    PubMed Central

    Qin, Ting-Wu; Chen, Qingshan; Sun, Yu-Long; Steinmann, Scott P.; Amadio, Peter C.; An, Kai-Nan; Zhao, Chunfeng

    2014-01-01

    The purpose of this study was to characterize the mechanical behavior of tendon slices with different thicknesses. Tendon slices of 100, 200, 300, 400, and 500 μm thickness were mechanically tested. The 300 μm slices were further tested for strength and modulus after 21,000-cycle fatigue testing under different applied strain levels (0, 1, 3, 5, 8, 10, and 12%). The tendon slice structure, morphology, and viability of bone marrow stromal cells (BMSCs) seeded onto the slices were also examined with histology, scanning electron microscopy, and vital cell labeling, respectively. Tendon slices 300 μm or more in thickness had similar ultimate tensile strength and Young's modulus to the intact tendon bundle. A strain of 5% or less did not cause any structural damage, nor did it change the mechanical properties of a 300 μm-thick tendon slice after 21,000-cycle fatigue testing. BMSCs were viable between and on the tendon slices after 2 weeks in tissue culture. This study demonstrated that, if tendon slices are used as a scaffold for tendon tissue engineering, slices 300 μm or more in thickness would be preferable from a mechanical strength point of view. If mechanical stimulation is performed for seeded-cell preparations, 5% strain or less would be appropriate. PMID:22323314

  6. Effect of recombinant human platelet-derived growth factor-BB-coated sutures on Achilles tendon healing in a rat model: A histological and biomechanical study

    PubMed Central

    Cummings, Stephen H; Grande, Daniel A; Hee, Christopher K; Kestler, Hans K; Roden, Colleen M; Shah, Neil V; Razzano, Pasquale; Dines, David M; Chahine, Nadeen O

    2012-01-01

    Purpose: Repairing tendon injuries with recombinant human platelet-derived growth factor-BB has potential for improving surgical outcomes. Augmentation of sutures, a critical component of surgical tendon repair, by coating with growth factors may provide a clinically useful therapeutic device for improving tendon repair. Therefore, the purpose of this study was to (a) coat Vicryl sutures with a defined dose of recombinant human platelet-derived growth factor-BB without additional coating excipients (e.g. gelatin), (b) quantify the recombinant human platelet-derived growth factor-BB released from the suture, and (c) use the recombinant human platelet-derived growth factor-BB-coated sutures to enhance tendon repair in a rat Achilles tendon transection model. Methods: Vicryl sutures were coated with 0, 0.3, 1.0, and 10.0 mg/mL concentrations of recombinant human platelet-derived growth factor-BB using a dip-coating process. In vitro release was quantified by an enzyme-linked immunosorbent assay. Acutely transected rat Achilles tendons were repaired using one of the four suture groups (n = 12 per group). Four weeks following repair, the tensile biomechanical and histological (i.e. collagen organization and angiogenesis) properties were determined. Results: A dose-dependent bolus release of recombinant human platelet-derived growth factor-BB occurred within the first hour in vitro, followed by a gradual release over 48 h. There was a significant increase in ultimate tensile strength (p < 0.01) in the two highest recombinant human platelet-derived growth factor-BB dose groups (1.9 ± 0.5 and 2.1 ± 0.5 MPa) relative to controls (1.0 ± 0.2 MPa). The modulus significantly increased (p = 0.031) with the highest recombinant human platelet-derived growth factor-BB dose group (7.2 ± 3.8 MPa) relative to all other groups (control: 3.5 ± 0.9 MPa). No significant differences were identified for the maximum load or stiffness. The histological collagen and angiogenesis scores

  7. Test-retest reliability and the minimal detectable change for achilles tendon length: a panoramic ultrasound assessment.

    PubMed

    Ryan, Eric D; Rosenberg, Joseph G; Scharville, Michael J; Sobolewski, Eric J; Thompson, Brennan J; King, Gilbert E

    2013-12-01

    The purpose of the present study was to examine test-retest reliability and minimal detectable change (MDC) values for Achilles tendon (AT) length determined using panoramic ultrasound (US) imaging. Seventeen men (age = 21.0 ± 2.3 y) visited the laboratory on two separate days, where AT length was examined along the mid-longitudinal axis of the right lower leg with a portable B-mode panoramic US device. These measures were found to have acceptable reliability with intra-class correlation coefficient (ICC) and standard error of measurement (SEM) values of 0.954 and 4.43 mm (SEM% of the mean = 2.37%), respectively. In addition, the MDC for the panoramic US assessment of AT length was 12.27 mm (MDC% of the mean = 6.57%). These findings suggest that panoramic US imaging is a reliable technique for detection of clinically relevant changes in AT length and may therefore be a practical and time-efficient clinical tool for future studies examining AT length in vivo.

  8. An anatomic and clinical study of the adductor magnus tendon-descending genicular artery bone flap.

    PubMed

    Huang, Dong; Wang, Hai-Wen; Xu, Da-Chuan; Wang, Hong-Gang; Wu, Wei-Zhi; Zhang, Hui-Ru

    2011-01-01

    The composite tissue flap of the descending genicular vessels with the adductor magnus tendon is a newly developed, reliable method to repair the Achilles tendon and relevant skin defects. The aim of this study was to evaluate the anatomy of the adductor magnus tendon-descending genicular artery bone flap, and the feasibility and value for the repair of the Achilles tendon and relevant skin defects. There were 34 adult specimens used for the anatomy of this flap. The descending genicular artery originates 10.5 ± 1.6 cm above the adductor tubercle, with a diameter of 1.8 ± 0.6 mm and a length of 1.2 ± 0.5 cm. Its articular branch is distributed in the adductor magnus tendon and the medial condyle of the femur. The saphenous branch has a diameter of 1.1 ± 0.3 mm and is distributed in the skin of the upper medial calf. A total of 16 cases of trauma-induced Achilles tendon damage and calcaneus and skin defects were repaired with the vascularized adductor magnus tendon bone flap, including the reconstruction of Achilles tendon insertion and repair of relevant skin defects. All of the composite tissue flaps were viable, the skin sensation of the flaps was recovered, and all patients walked with a normal gait. Our results suggested that the adductor magnus tendon-descending genicular artery bone flap is an alternative method to repair composite tissue defects of the Achilles tendon.

  9. Quantification of Posterior Ankle Exposure Through an Achilles Tendon-Splitting Versus Posterolateral Approach

    DTIC Science & Technology

    2012-10-01

    Cornelius, NC Research funded by the United States Army Institute of Surgical Research; cadavers provided by the Combat Extremity Surgery Course...or other nonprofit organization with which one or more of the authors is associated Corresponding Author: Jeanne C Patzkowksi, MD Orthopaedic Surgery ...Prospective studies will help determine if the tendon-splitting approach is a safe and clinically useful approach for surgeries in which direct access

  10. Calf muscle-tendon lengths before and after Tendo-Achilles lengthenings and gastrocnemius lengthenings for equinus in cerebral palsy and idiopathic toe walking.

    PubMed

    Jahn, Jessica; Vasavada, Anita N; McMulkin, Mark L

    2009-06-01

    The calf muscle-tendon lengths in children exhibiting equinus gait in two clinical populations, cerebral palsy (CP) and idiopathic toe walking (ITW), were examined to compare the effects of diagnosis and two different surgical procedures, Tendo-Achilles lengthening (TAL) versus Vulpius procedure (VP) gastrocnemius recession. Pre- and post-surgical gait data were obtained from 38 subjects (58 limbs) and 38 age-matched controls. Peak muscle-tendon lengths increased following surgery in 84% of limbs. For medial gastrocnemius (MGAS) and lateral gastrocnemius (LGAS) in stance, muscle-tendon lengths increased significantly following TAL surgeries but were not significantly different pre- and post-VP surgeries. For soleus (SOL) (swing and stance) and MGAS and LGAS (swing), muscle-tendon lengths increased significantly following both TAL and VP surgeries. Pre-operatively, muscle-tendon lengths were significantly shorter for the TAL group compared to the VP group; however, post-operatively the lengths were not significantly different between the surgeries. There were no significant differences between CP and ITW patients or indications that the surgery affected the groups differently. The change in length following surgery was well correlated to the subjects' initial muscle-tendon length.

  11. Tendon tissue engineering: progress, challenges, and translation to the clinic.

    PubMed

    Shearn, J T; Kinneberg, K R; Dyment, N A; Galloway, M T; Kenter, K; Wylie, C; Butler, D L

    2011-06-01

    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.

  12. Bioreactor optimization of tissue engineered rabbit flexor tendons in vivo.

    PubMed

    Thorfinn, J; Angelidis, I K; Gigliello, L; Pham, H M; Lindsey, D; Chang, J

    2012-02-01

    Tissue-engineered rabbit flexor tendons reseeded with cells are stronger in vitro after culture in a bioreactor. It is not known whether this effect persists in vivo. Tenocytes from New Zealand white rabbits were seeded onto rabbit rear paw flexor tendons that were deprived of cells and exposed to cyclic strain in a bioreactor. Reseeded constructs that were kept unloaded in a medium for 5 days were used as controls. The tendons were implanted to bridge a zone II defect in the rabbit. After explantation 4 weeks later, the ultimate tensile strength (UTS) and elastic modulus (EM) were determined. Tendon constructs that were exposed to cyclic strain had significantly improved UTS and EM. Histology showed that cellularity was increased in the bioreactor tendons.

  13. Achilles tendon rupture in an elite athlete following multiple injection therapies.

    PubMed

    Hamilton, Bruce; Remedios, Denis; Loosemore, Mike; Maffulli, Nicola

    2008-11-01

    Achilles tendinopathy is common, and its management continues to be challenging, especially in elite athletes. Despite a wide range of novel management options, none guarantees a rapid return to high level sporting activity. Eccentric exercise has been shown to reduce symptoms and normalise imaging abnormalities, but time constraints on professional athletes often make this an unrewarding isolated management strategy. Eccentric exercises concurrent with ongoing training may not be as successful as eccentric training alone, reducing one's confidence in this modality for the "in-season" tendinopathy in the elite athlete. When a professional athlete is faced with a tendinopathy recalcitrant to eccentric exercise, manual therapy and orthotics, a more invasive approach is often attempted to expedite a return to unencumbered training. Numerous injection therapies are described, ranging from homeopathic products to glucocorticosteroids. The robustness of the literature surrounding these techniques is variable, but when an athlete is desperate to return to full training, clinicians working with elite athletes are often tempted to utilise more empirical management options. We present a patient who illustrates the potential dangers of injection therapy in the elite athlete, in particular sequential injection therapy involving vascular sclerosants, which to our knowledge has not previously been described. Written consent for the presentation of this case was obtained from the athlete concerned.

  14. Functional evaluation of professional athletes treated with a mini-open technique for achilles tendon rupture

    PubMed Central

    Vadalà, Antonio; Lanzetti, Riccardo Maria; Ciompi, Alessandro; Rossi, Cristina; Lupariello, Domenico; Ferretti, Andrea

    2014-01-01

    Summary Introduction: in this study we report the functional results of 36 professional athletes treated with a combined percutaneous and mini-open technique. Methods: patients were evaluated with Victorian Institute of Sports Assessment-Achilles questionnaire (VISA-A), the objective 100-points Hannover scale and the Ergo-jump Bosco System device. Results: at a mean 28- month follow-up no re-rupture cases were observed. Six patients had minor complications. The Ergo-jump Bosco System device showed no significant differences in the side-to-side evaluation in regard to strength (−0.94%) and elasticity (+2.44%), while a significant post-operative loss was detected in the endurance trials (−6.78%). The Hannover scale showed an average score of 94.5, while the VISA-A had an average of 93.1. Thirty-one patients resumed their pre-operative sports activity level within five months from surgery. Conclusions: our results showed that the combined mini-open and percutaneous repair is an effective treatment for professional athletes, with satisfactory clinical and functional results, lack of major complications and a quick return to professional sports activity. PMID:25332932

  15. Repair of full-thickness tendon injury using connective tissue progenitors efficiently derived from human embryonic stem cells and fetal tissues.

    PubMed

    Cohen, Shahar; Leshansky, Lucy; Zussman, Eyal; Burman, Michael; Srouji, Samer; Livne, Erella; Abramov, Natalie; Itskovitz-Eldor, Joseph

    2010-10-01

    The use of stem cells for tissue engineering (TE) encourages scientists to design new platforms in the field of regenerative and reconstructive medicine. Human embryonic stem cells (hESC) have been proposed to be an important cell source for cell-based TE applications as well as an exciting tool for investigating the fundamentals of human development. Here, we describe the efficient derivation of connective tissue progenitors (CTPs) from hESC lines and fetal tissues. The CTPs were significantly expanded and induced to generate tendon tissues in vitro, with ultrastructural characteristics and biomechanical properties typical of mature tendons. We describe a simple method for engineering tendon grafts that can successfully repair injured Achilles tendons and restore the ankle joint extension movement in mice. We also show the CTP's ability to differentiate into bone, cartilage, and fat both in vitro and in vivo. This study offers evidence for the possibility of using stem cell-derived engineered grafts to replace missing tissues, and sets a basic platform for future cell-based TE applications in the fields of orthopedics and reconstructive surgery.

  16. Post-surgical care of a professional ballet dancer following calcaneal exostectomy and debridement with re-attachment of the left Achilles tendon.

    PubMed

    Kobsar, Bradley; Alcantara, Joel

    2009-03-01

    The extraordinary physical demands placed upon ballet dancers are only now being appreciated as comparable to that of other highly competitive athletic pursuits. The professional ballet dancer presents with an array of injuries associated with their physically vigorous performance requirements. In keeping with evidence-based practice, we describe the chiropractic care of a professional ballet dancer following surgical calcaneal exostectomy and debridement with re-attachment of the left Achilles tendon. The care provided involves an array of modalities from exercise and rehabilitation to spinal manipulative therapy.

  17. Endoscopic-Assisted Flexor Hallucis Longus Transfer: Harvest of the Tendon at Zone 2 or Zone 3.

    PubMed

    Lui, Tun Hing

    2015-12-01

    Flexor hallucis longus (FHL) tendon transfer is indicated for reconstruction of the Achilles tendon with a gap larger than 5 cm. The tendon can be harvested at zone 2 or zone 3 by minimally invasive techniques with the advantage of minimal soft-tissue dissection. The tendon can be harvested under the sustentaculum tali by zone 2 FHL tendoscopy. It is adequate for FHL transfer to the posterior calcaneal tubercle. If a double-thickness reconstruction of a huge gap of the Achilles tendon is indicated, the tendon can be harvested at the level of the hallux by means of a tendon stripper. However, the interconnection tendon of the master knot of Henry can be split together with the FHL or flexor digitorum longus tendon instead of being cut. Zone 2 FHL tendoscopy can be used to release the split tendon to complete the FHL harvest.

  18. 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

  19. Continuous, bilateral Achilles' tendon vibration is not detrimental to human walk.

    PubMed

    Courtine, G; Pozzo, T; Lucas, B; Schieppati, M

    2001-05-01

    Sensory feedback from the moving limbs contributes to the regulation of animal and human locomotion. However, the question of the specific role of the various modalities is still open. Further, functional loss of leg afferent fibres due to peripheral neuropathy does not always lead to major alteration in the gait pattern. In order to gain further insight on proprioceptive control of human gait, we applied vibratory tendon stimulation, known to recruit spindle primary afferent fibres, to both triceps surae muscles during normal floor walk. This procedure would disturb organisation and execution of walking, especially if spindles fire continuously and subjects are blindfolded. Vibration induced significant, though minor, changes in duration and length of stance and swing phase, and on speed of walking and kinematics of lower limb segments. No effect was induced on angular displacement of the ankle joint or trunk and head kinematics. This paucity of effects was at variance with the perception of the subjects, who reported illusion of leg stiffness and gait imbalance. These findings would speak for a selective gating of Ia input during locomotion and emphasise the notion that the central nervous system can cope with an unusual continuous input along the Ia fibres from a key muscle like the soleus.

  20. Early functional rehabilitation versus traditional immobilization for surgical Achilles tendon repair after acute rupture: a systematic review of overlapping meta-analyses

    PubMed Central

    Zhao, Jia-Guo; Meng, Xiao-Hui; Liu, Lin; Zeng, Xian-Tie; Kan, Shi-Lian

    2017-01-01

    Several meta-analyses comparing early functional rehabilitation and traditional immobilization following surgical Achilles tendon repair after acute rupture have been published. However, they have led to conflicting conclusions. The aims of this systematic review were to select high-quality meta-analyses from multiple discordant meta-analyses and to provide a postoperative rehabilitation strategy following surgical repair using currently available evidence. We performed a comprehensive search using the PubMed and Embase databases and the Cochrane Library. Assessment of Multiple Systematic Reviews (AMSTAR) instrument was used to assess the methodological quality. Three investigators independently applied the Jadad decision algorithm. Their results were then compared to ensure selection of a meta-analysis that provided the highest quality of evidence. Six meta-analyses met the eligibility criteria. AMSTAR scores ranged from 6 to 10. According to the Jadad decision algorithm, a high-quality meta-analysis with a greater number of RCTs was selected. This meta-analysis showed that early functional rehabilitation was superior to cast immobilization in terms of patient satisfaction and the time to return to pre-morbid sporting levels. There were no differences regarding major complications or the time before return to prior employment and sporting activity. Thus, we recommend early functional rehabilitation as the postoperative strategy for acute Achilles tendon ruptures. PMID:28054658

  1. Faut-il préférer une technique chirurgicale dans le traitement des ruptures du tendon d'Achille?

    PubMed Central

    Hani, Redouane; Kharmaz, Mohammed; Berrada, Mohammed Saleh

    2015-01-01

    La rupture du tendon d'Achille est de plus en plus fréquente dans le monde et dans notre pays en raison du développement considérable des activités sportives, de l'accroissement de leur intensité et de l'absence de moyens de prévention. Notre travail porte sur une étude concernant 58 cas de rupture du tendon d'Achille, avec un recul moyen compris entre 5 mois et 80 mois. L’âge moyen était de 36 ans, tous les patients inclus ont tous bénéficier d'un traitement chirurgical. Le but de notre étude étant de souligner la supériorité d'une technique chirurgicale par rapport à une autre dans la prise en charge, ainsi qu'une mise au point sur les différents aspects épidémiologiques, cliniques, thérapeutiques et post-thérapeutiques de cette lésion. PMID:26161208

  2. Hoffmann reflex is increased after 14 days of daily repeated Achilles tendon vibration for the soleus but not for the gastrocnemii muscles.

    PubMed

    Lapole, Thomas; Pérot, Chantal

    2012-02-01

    In a previous study, Achilles tendon vibrations were enough to improve the triceps surae (TS) activation capacities and also to slightly increase TS Hoffmann reflex (H-reflex) obtained by summing up soleus (Sol) and gastrocnemii (GM and GL) EMGs. The purpose of the present study was to analyze separately Sol and GM or GL reflexes to account for different effects of the vibrations on the reflex excitability of the slow soleus and of the gastrocnemii muscles. A control group (n = 13) and a vibration group (n = 16) were tested in pre-test and post-test conditions. The Achilles tendon vibration program consisted of 1 h of daily vibration (frequency: 50 Hz) applied during 14 days. Maximal Sol, GM and GL H-reflexes, and M-waves were recorded, and their H(max)/M(max) ratios gave the index of reflex excitability. After the vibration protocol, only Sol H(max)/M(max) was enhanced (p < 0.001). The enhanced Sol reflex excitability after vibration is in favor of a decrease in the pre-synaptic inhibition due to the repeated vibrations and the high solicitation of the reflex pathway. Those results of a short period of vibration applied at rest may be limited to the soleus because of its high density in muscle spindles and slow motor units, both structures being very sensitive to vibrations.

  3. Polymorphisms within the COL5A1 gene and regulators of the extracellular matrix modify the risk of Achilles tendon pathology in a British case-control study.

    PubMed

    Brown, Karryn L; Seale, Kirsten B; El Khoury, Louis Y; Posthumus, Michael; Ribbans, William J; Raleigh, Stuart M; Collins, Malcolm; September, Alison V

    2016-08-19

    Several genetic loci have been associated with risk of Achilles tendon pathology (ATP) within South African and Australian populations. The aim of this study was, therefore, to evaluate eight previously implicated genetic variants in an independent British population. A total of 130 asymptomatic controls (CON) and 112 participants clinically diagnosed with ATP comprising 87 individuals with chronic Achilles tendinopathy (TEN) and 25 with Achilles tendon ruptures (RUP) were included. All participants were genotyped for variants within the COL5A1, MIR608, IL-1β, IL-6 and CASP8 genes. Primary findings implicated COL5A1 and CASP8. Three inferred allele combinations constructed from COL5A1 rs12722, rs3196378 and rs71746744 were identified as risk modifiers. The T-C-D combination was associated with increased risk of ATP (P = 0.023) and RUP (P < 0.001), the C-A-I combination was associated with increased risk of ATP (P = 0.011), TEN (P = 0.011) and RUP (P = 0.011) and the C-C-D combination was associated with decreased risk of ATP (P = 0.011) and RUP (P = 0.004). The CASP8 rs3834129 DD genotype was associated with decreased risk of TEN (P = 0.020, odds ratio: 0.45, 95% confidence interval: 0.22-0.90) and the CASP8 I-G (rs3834129-rs1045485) inferred allele combination was associated with increased risk of TEN (P = 0.031). This study further highlights the importance of polymorphisms within COL5A1 and CASP8 in the aetiology of ATP.

  4. The Role of Bioreactors in Ligament and Tendon Tissue Engineering.

    PubMed

    Mace, James; Wheelton, Andy; Khan, Wasim S; Anand, Sanj

    2016-01-01

    Bioreactors are pivotal to the emerging field of tissue engineering. The formation of neotissue from pluripotent cell lineages potentially offers a source of tissue for clinical use without the significant donor site morbidity associated with many contemporary surgical reconstructive procedures. Modern bioreactor design is becoming increasingly complex to provide a both an expandable source of readily available pluripotent cells and to facilitate their controlled differentiation into a clinically applicable ligament or tendon like neotissue. This review presents the need for such a method, challenges in the processes to engineer neotissue and the current designs and results of modern bioreactors in the pursuit of engineered tendon and ligament.

  5. Efficient decellularization for tissue engineering of the tendon-bone interface with preservation of biomechanics

    PubMed Central

    Foehr, Peter; Kuempel, Katharina; Wagner, Alexandra; Tuebel, Jutta; Deimling, Constantin V.; Burgkart, Rainer H.

    2017-01-01

    Interfaces between tendon/ligament and bone (“entheses”) are highly specialized tissues that allow for stress transfer between mechanically dissimilar materials. Entheses show very low regenerative capacity resulting in high incidences of failure after surgical repair. Tissue engineering is a promising approach to recover functionality of entheses. Here, we established a protocol to decellularize porcine entheses as scaffolds for enthesis tissue engineering. Chemical detergents as well as physical treatments were investigated with regard to their efficiency to decellularize 2 mm thick porcine Achilles tendon entheses. A two-phase approach was employed: study 1 investigated the effect of various concentrations of sodium dodecyl sulfate (SDS) and t-octylphenoxypolyethoxy-ethanol (Triton X-100) as decellularization agents. The most efficient combination of SDS and Triton was then carried forward into study 2, where different physical methods, including freeze-thaw cycles, ultrasound, perfusion, and hydrostatic washing were used to enhance the decellularization effect. Cell counts, DNA quantification, and histology showed that washing with 0.5% SDS + 1% Triton X-100 for 72 h at room temperature could remove ~ 98% cells from the interface. Further investigation of physical methods proved that washing under 200 mmHg hydrostatic pressure shortened the detergent exposing time from 72 h to 48 h. Biomechanical tensile testing showed that the biomechanical features of treated samples were preserved. Washing under 200 mmHg hydrostatic pressure with 0.5% SDS + 1% Triton X-100 for 48 h efficiently decellularized entheses with preservation of matrix structure and biomechanical features. This protocol can be used to efficiently decellularize entheses as scaffolds for tissue engineering. PMID:28170430

  6. Bilateral traumatic rupture of Achilles tendons in absence of risk factors treated with percutaneous technique and platelet-rich plasma: a case report.

    PubMed

    Guelfi, Matteo; Pantalone, Andrea; Vanni, Daniele; Rosati, Denise; Guelfi, Marco G B; Salini, Vincenzo

    2014-09-01

    We present a clinical case of a 52-year-old man with bilateral traumatic rupture of the Achilles tendon (AT) in absence of risk factors. In medical history, the patient does not report pre-existing tendon diseases. AT ruptures occurred following a skiing injury in which the forward fall caused a severe stress and elongation of the AT. Associated with tendon injury there was a fracture of the right humeral greater tuberosity. The patient was subjected to percutaneous tenorraphy according to Maffulli's technique and subsequently topical injection of autologous platelet-rich plasma (PRP) 7 days after the injury. After surgery, the patient followed an accelerated rehabilitation protocol, allowing the weight bearing with guards (Rom-Walker) and crutches to four weeks then freely to 8 weeks. We performed a clinical (AOFAS ankle-hindfoot score) and ultrasonography follow-up at month 1, 3, 6 and 12, with excellent results in the end. To the best of our knowledge bilateral cases like this have not been described in the literature.

  7. The long head of the biceps tendon is a suitable cell source for tendon tissue regeneration

    PubMed Central

    Pietschmann, Matthias F.; Gülecyüz, Mehmet F.; Ficklscherer, Andreas; Jansson, Volkmar; Müller, Peter E.

    2014-01-01

    Introduction Tendon tissue engineering (TTE) tries to produce tendinous tissue of high quality to replace dysfunctional tissue. One possible application of TTE might be the replacement of ruptured tissue of the rotator cuff. Autologous tenocytes seem to be most suitable as no differentiation in vitro is necessary. Today it is still uncertain if there is a difference between tendon-derived cells (TDC) of different native tissues. Moreover, the search for suitable scaffolds is another important issue in TTE. Material and methods This study compared TDC of the long head of the biceps tendon (LHB), the anterior cruciate ligament (ACL) and the tendon of the musculus semitendinosus (TMS). The TDC were isolated using the cell migration method. Cell morphology was assessed using light microscopy and gene expression was performed using polymerase chain reaction (PCR). Afterwards, cell seeding efficiency and proliferation were tested on a collagen I scaffold using the WST-1 assay. Results were confirmed using H + E staining. Results The TDC of the LHB showed higher expression levels of collagen type I and decorin (p < 0.01) compared to TDC of other origin. Results showed efficient cell seeding and proliferation within the scaffold. Proliferation within the scaffold was not as high as when cells were cultivated without a scaffold. Conclusions The TDC of the LHB seems to be the most suitable cell source. Further research is necessary to find out if the results can be transferred to an in vivo model. The new collagen I scaffold seems to offer an opportunity to combine good biocompatibility and mechanical strength. PMID:25097592

  8. Plantaris Excision Reduces Pain in Midportion Achilles Tendinopathy Even in the Absence of Plantaris Tendinosis

    PubMed Central

    Calder, James D. F.; Stephen, Joanna M.; van Dijk, C. Niek

    2016-01-01

    Background: It is becoming increasingly apparent that the plantaris can contribute to symptoms in at least a subset of patients with midportion Achilles tendinopathy. However, the nature of its involvement remains unclear. Purpose: To determine whether excised plantaris tendons from patients with midportion Achilles tendinopathy display tendinopathic changes and whether the presence of such changes affect clinical outcomes. Study Design: Case series; Level of evidence, 4. Methods: Sixteen plantaris tendons in patients with midportion Achilles tendinopathy recalcitrant to conservative management underwent histological examination for the presence of tendinopathic changes. All patients had imaging to confirm the presence of the plantaris tendon adherent to or invaginated into the focal area of Achilles tendinosis. Visual analog scale (VAS) and Foot and Ankle Outcome Score (FAOS) results were recorded pre- and postoperatively. Results: Sixteen patients (mean age, 26.2 years; range, 18-47 years) underwent surgery, with a mean follow-up of 14 months (range, 6-20 months). The plantaris tendon was histologically normal in 13 of 16 cases (81%). Inflammatory changes in the loose peritendinous connective tissue surrounding the plantaris tendon were evident in all cases. There was significant improvement in mean VAS scores (P < .05) and all domains of the FAOS postoperatively (P < .05). Conclusion: The absence of any tendinopathic changes in the excised plantaris of 13 patients who clinically improved suggests plantaris involvement with Achilles tendinopathy may not yet be fully understood and supports the concept that this may be a compressive or a frictional phenomenon rather than purely tendinopathic. PMID:28203584

  9. Achilles tendinosis: treatment options.

    PubMed

    Lopez, Roberto Gabriel L; Jung, Hong-Geun

    2015-03-01

    Athletes usually complain of an ongoing or chronic pain over the Achilles tendon, but recently even non-athletes are experiencing the same kind of pain which affects their daily activities. Achilles tendinosis refers to a degenerative process of the tendon without histologic or clinical signs of intratendinous inflammation. Treatment is based on whether to stimulate or prevent neovascularization. Thus, until now, there is no consensus as to the best treatment for this condition. This paper aims to review the common ways of treating this condition from the conservative to the surgical options.

  10. Achilles Tendinosis: Treatment Options

    PubMed Central

    Lopez, Roberto Gabriel L.

    2015-01-01

    Athletes usually complain of an ongoing or chronic pain over the Achilles tendon, but recently even non-athletes are experiencing the same kind of pain which affects their daily activities. Achilles tendinosis refers to a degenerative process of the tendon without histologic or clinical signs of intratendinous inflammation. Treatment is based on whether to stimulate or prevent neovascularization. Thus, until now, there is no consensus as to the best treatment for this condition. This paper aims to review the common ways of treating this condition from the conservative to the surgical options. PMID:25729512

  11. Intermittent pneumatic compression reduces the risk of deep vein thrombosis during post-operative lower limb immobilisation: a prospective randomised trial of acute ruptures of the Achilles tendon.

    PubMed

    Domeij-Arverud, E; Labruto, F; Latifi, A; Nilsson, G; Edman, G; Ackermann, P W

    2015-05-01

    Deep vein thrombosis is a common complication of immobilising the lower limb after surgery. We hypothesised that intermittent pneumatic compression (IPC) therapy in outpatients who had undergone surgical repair of acute ruptures of the Achilles tendon could reduce the incidence of this problem. A total of 150 patients who had undergone surgical repair of the Achilles tendon were randomised to either treatment with IPC for six hours per day (n = 74) under an orthosis or treatment as usual (n = 74) in a plaster cast without IPC. At two weeks post-operatively, the incidence of deep vein thrombosis was assessed using blinded, double-reported compression duplex ultrasound. At this point, IPC was discontinued and all patients were immobilised in an orthosis for a further four weeks. At six weeks post-operatively, a second compression duplex ultrasound scan was performed. At two weeks, the incidence of deep vein thrombosis was 21% in the treated group and 37% in the control group (p = 0.042). Age over 39 years was found to be a strong risk factor for deep vein thrombosis (odds ratio (OR) = 4.84, 95% confidence interval (CI) 2.14 to 10.96). Treatment with IPC, corrected for age differences between groups, reduced the risk of deep vein thrombosis at the two-week point (OR = 2.60; 95% CI 1.15 to 5.91; p =0.022). At six weeks, the incidence of deep vein thrombosis was 52% in the treated group and 48% in the control group (OR 0.94, 95% CI 0.49 to 1.83). IPC appears to be an effective method of reducing the risk of deep vein thrombosis in the early stages of post-operative immobilisation of outpatients. Further research is necessary to elucidate whether it can confer similar benefits over longer periods of immobilisation and in a more heterogeneous group of patients.

  12. Interaction between gastrocnemius medialis fascicle and Achilles tendon compliance: a new insight on the quick-release method.

    PubMed

    Farcy, Stevy; Nordez, Antoine; Dorel, Sylvain; Hauraix, Hugo; Portero, Pierre; Rabita, Giuseppe

    2014-02-01

    The insufficient temporal resolution of imaging devices has made the analysis of very fast movements, such as those required to measure active muscle-tendon unit stiffness, difficult. Thus the relative contributions of tendon, aponeurosis, and fascicle to muscle-tendon unit compliance remain to be determined. The present study analyzed the dynamic interactions of fascicle, tendon, and aponeurosis in human gastrocnemius medialis during the first milliseconds of an ankle quick-release movement, using high-frame-rate ultrasonography (2,000 frames/s). Nine subjects performed the tests in random order at six levels of maximal voluntary contraction (MVC) (30% to 80% of MVC). These tests were carried out with the ultrasound probe placed on the muscle belly and on the myotendinous junction. Tendon, muscle fascicle, and aponeurosis length changes were quantified in relation to shortening of the muscle-tendon unit during the first few milliseconds following the release. The tendon was the main contributor (around 72%) to the shortening of the muscle-tendon unit, whereas the muscle fascicle and aponeurosis contributions were 18% and 10%, respectively. Because these structures can be considered in series, the quantified contributions can be regarded as relative contributions to muscle-tendon compliance. These contributions were not modified with the level of MVC or the time range used for the analysis between 10 and 25 ms. The constant contribution of tendon, muscle fascicle, and aponeurosis to muscle-tendon unit compliance may help to simplify the mechanism of compliance regulation and to maintain the important role of tendons in enhancing work output and movement efficiency.

  13. Achilles Tendon Disorders

    MedlinePlus

    ... Foot & Ankle Conditions Articles & Helpful Tips Articles by Type Athletes Children Diabetes General Seasonal Seniors Women When to Visit a ... Foot & Ankle Conditions Articles & Helpful Tips Articles by Type Athletes Children Diabetes General Seasonal Seniors Women When to Visit a ...

  14. Percutaneous Achilles Tendon Lengthening

    MedlinePlus

    You may be trying to access this site from a secured browser on the server. Please enable scripts and reload this page. ... What Kind of Shape Are Your Feet In? Foot Changes During Pregnancy Conditions Ailments ...

  15. Achilles tendon rupture - aftercare

    MedlinePlus

    ... off the ground, to go from walking to running, or to running uphill Tripped and fell, or had another accident ... and stretch before any exercise Avoid high-heeled shoes Ask your provider if it is OK for ...

  16. Achilles Tendon Rupture

    MedlinePlus

    ... activities. Choose running surfaces carefully. Avoid or limit running on hard or slippery surfaces. Dress properly for cold-weather training and wear well-fitting athletic shoes with proper cushioning in the heels. Increase training ...

  17. Can Achilles tendon be used as a new distal landmark for coronal tibial component alignment in total knee replacement surgery? An observational MRI study

    PubMed Central

    Tiftikçi, Uğur; Serbest, Sancar; Burulday, Veysel

    2017-01-01

    Background In total knee arthroplasty, it is better to use more than one reference point for correct alignment of the components. By measuring the distances of Achilles tendon (AT) and other conventional landmarks from the mechanical axis in magnetic resonance imaging (MRI) of the ankle, we aimed to demonstrate that, as a novel landmark which can help for correct alignment in the coronal plane, AT is a better option than other landmarks. Materials and methods This retrospective study was done on 53 ankle MRIs that met the criteria for inclusion to the study among 158 ankle MRIs. After identification of the mechanical axis, the distances of distal landmarks, which were extensor hallucis longus tendon (EHLT), tibialis anterior tendon (TAT), dorsalis pedis artery (DPA), AT, extensor digitorum longus tendon (EDLT), and malleoli, were measured from the mechanical axis and were statistically evaluated. Results In proximal measurements, the distances of the landmarks to the mechanical axis (on average) were AT, 2.64±1.62 mm lateral; EHLT, 3.89±2.45 mm medial; DPA, 4.69±2.39 mm medial; TAT, 8.24±3.60 mm medial; and EDLT, 14.2±4.14 mm lateral (P<0.001). In distal measurements, the distances of the landmarks to the mechanical axis (on average) were AT, 1.99±1.24 mm medial; EHLT, 4.27±2.49 mm medial; DPA, 4.79±2.10 mm medial; TAT, 12.9±4.07 mm medial; and EDLT, 12.18±4.17 mm lateral (P<0.001). Conclusion In this study, the mechanical axis line, which is the center of talus, passes through the AT. Our MRI investigations showed that the AT, EHLT, DPA, and malleolar center (3–5 mm medial) may help in correct alignment. PMID:28144149

  18. Cryotherapy suppresses tendon inflammation in an animal model

    PubMed Central

    Zhang, Jianying; Pan, Tiffany; Wang, James H.-C.

    2015-01-01

    Summary Cryotherapy (or cold treatment) has been a popular treatment to relieve pain caused by injuries to tissues such as tendons. However, the exact mechanisms behind the beneficial effects of cryotherapy in tendons remain largely unclear. As prostaglandin E2 (PGE2) is known to be a major mediator of acute inflammation in tissues, which is related to tissue pain, we hypothesized that the beneficial effects of cryotherapy in tendons are mediated by downregulation of PGE2 levels. To test this hypothesis, we applied cold treatment to mouse patellar and Achilles tendons using two animal models: exhaustive mouse treadmill running and acute mouse tendon injury by needle penetration. We then measured the levels of PGE2 and protein expression levels of COX-2, an enzyme responsible for PGE2 production in tissues, under both experimental conditions. We found that treadmill running increased PGE2 levels in both patellar and Achilles tendons compared to control mice without running. Cold treatment for 30 min after treadmill running was sufficient to reduce PGE2 levels to near baseline control levels in both tendons. An extension of cold treatment to 60 min resulted only in a marginal decrease in patellar tendons, but a marked decrease in Achilles tendons. Moreover, COX-2 protein levels in both tendons were also lowered by cold treatment, suggesting that the reduction of PGE2 levels in tendons by cold treatment is at least in part due to the decreased COX-2 expression. Similarly, in the acutely injured tendons, 30 min of cold treatment after needle penetration reduced PGE2 levels when compared to the controls at room temperature (22°C). This decrease was sustained up to at least 3 h after the administration of cryotherapy. Given that PGE2 is a known pain sensitiser, the results of this study suggest that the ability of cold treatment to reduce pain may be attributable to its ability to decrease PGE2 production in tendons. PMID:26594634

  19. Mechanical properties of tendon and aponeurosis of human gastrocnemius muscle in vivo.

    PubMed

    Muramatsu, T; Muraoka, T; Takeshita, D; Kawakami, Y; Hirano, Y; Fukunaga, T

    2001-05-01

    Load-strain characteristics of tendinous tissues (Achilles tendon and aponeurosis) were determined in vivo for human medial gastrocnemius (MG) muscle. Seven male subjects exerted isometric plantar flexion torque while the elongation of tendinous tissues of MG was determined from the tendinous movements by using ultrasonography. The maximal strain of the Achilles tendon and aponeurosis, estimated separately from the elongation data, was 5.1 +/- 1.1 and 5.9 +/- 1.6%, respectively. There was no significant difference in strain between the Achilles tendon and aponeurosis. In addition, no significant difference in strain was observed between the proximal and distal regions of the aponeurosis. The results indicate that tendinous tissues of the MG are homogeneously stretched along their lengths by muscle contraction, which has functional implications for the operation of the human MG muscle-tendon unit in vivo.

  20. Presence of a non-neuronal cholinergic system and occurrence of up- and down-regulation in expression of M2 muscarinic acetylcholine receptors: new aspects of importance regarding Achilles tendon tendinosis (tendinopathy).

    PubMed

    Bjur, Dennis; Danielson, Patrik; Alfredson, Håkan; Forsgren, Sture

    2008-02-01

    Limited information is available concerning the existence of a cholinergic system in the human Achilles tendon. We have studied pain-free normal Achilles tendons and chronically painful Achilles tendinosis tendons with regard to immunohistochemical expression patterns of the M(2) muscarinic acetylcholine receptor (M(2)R), choline acetyltransferase (ChAT), and vesicular acetylcholine transporter (VAChT). M(2)R immunoreactivity was detected in the walls of blood vessels. As evidenced via parallel staining for CD31 and alpha-smooth muscle actin, most M(2)R immunoreactivity was present in the endothelium. M(2)R immunoreactivity also occured in tenocytes, which regularly immunoreact for vimentin. The degree of M(2)R immunoreactivity was highly variable, tendinosis tendons that exhibit hypercellularity and hypervascularity showing the highest levels of immunostaining. Immunoreaction for ChAT and VAChT was detected in tenocytes in tendinosis specimens, particularly in aberrant cells. In situ hybridization revealed that mRNA for ChAT is present in tenocytes in tendinosis specimens. Our results suggest that autocrine/paracrine effects occur concerning the tenocytes in tendinosis. Up-regulation/down-regulation in the levels of M(2)R immunoreactivity possibly take place in tenocytes and blood vessel cells during the various stages of tendinosis. The presumed local production of acetylcholine (ACh), as evidenced by immunoreactivity for ChAT and VAChT and the detection of ChAT mRNA, appears to evolve in response to tendinosis. These observations are of importance because of the well-known vasoactive, trophic, and pain-modulating effects that ACh is known to have and do unexpectedly establish the presence of a non-neuronal cholinergic system in the Achilles tendon.

  1. Methods of Assessing Human Tendon Metabolism and Tissue Properties in Response to Changes in Mechanical Loading.

    PubMed

    Heinemeier, Katja M; Kjaer, Michael; Magnusson, S Peter

    2016-01-01

    In recent years a number of methodological developments have improved the opportunities to study human tendon. Microdialysis enables sampling of interstitial fluid in the peritendon tissue, while sampling of human tendon biopsies allows direct analysis of tendon tissue for gene- and protein expression as well as protein synthesis rate. Further the (14)C bomb-pulse method has provided data on long-term tissue turnover in human tendon. Non-invasive techniques allow measurement of tendon metabolism (positron emission tomography (PET)), tendon morphology (magnetic resonance imaging (MRI)), and tendon mechanical properties (ultrasonography combined with force measurement during movement). Finally, 3D cell cultures of human tendon cells provide the opportunity to investigate cell-matrix interactions in response to various interventions.

  2. Low level laser therapy reduces inflammation in activated Achilles tendinitis

    NASA Astrophysics Data System (ADS)

    Bjordal, Jan M.; Iversen, Vegard; Lopes-Martins, Rodrigo Alvaro B.

    2006-02-01

    Objective: Low level laser therapy (LLLT) has been forwarded as therapy for osteoarthritis and tendinopathy. Results in animal and cell studies suggest that LLLT may act through a biological mechanism of inflammatory modulation. The current study was designed to investigate if LLLT has an anti-inflammatory effect on activated tendinitis of the Achilles tendon. Methods: Seven patients with bilateral Achilles tendonitis (14 tendons) who had aggravated symptoms by pain-inducing activity immediately prior to the study. LLLT (1.8 Joules for each of three points along the Achilles tendon with 904nm infrared laser) and placebo LLLT were administered to either Achilles tendons in a random order to which patients and therapist were blinded. Inflammation was examined by 1) mini-invasive microdialysis for measuring the concentration of inflammatory marker PGE II in the peritendinous tissue, 2) ultrasound with Doppler measurement of peri- and intratendinous blood flow, 3) pressure pain algometry and 4) single hop test. Results: PGE 2- levels were significantly reduced at 75, 90 and 105 minutes after active LLLT compared both to pre-treatment levels (p=0.026) and to placebo LLLT (p=0.009). Changes in pressure pain threshold (PPT) were significantly different (P=0.012) between groups. PPT increased by a mean value of 0.19 kg/cm2 [95%CI:0.04 to 0.34] after treatment in the active LLLT group, while pressure pain threshold was reduced by -0.20 kg/cm2 [95%CI:-0.45 to 0.05] after placebo LLLT. Conclusion: LLLT can be used to reduce inflammatory musculskeletal pain as it reduces inflammation and increases pressure pain threshold levels in activity-induced pain episodes of Achilles tendinopathy.

  3. 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.

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

    PubMed Central

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

    2016-01-01

    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. PMID:27811845

  5. Crosslinkable Hydrogels Derived from Cartilage, Meniscus, and Tendon Tissue

    PubMed Central

    Visser, Jetze; Levett, Peter A.; te Moller, Nikae C.R.; Besems, Jeremy; Boere, Kristel W.M.; van Rijen, Mattie H.P.; de Grauw, Janny C.; Dhert, Wouter J.A.; van Weeren, P. René

    2015-01-01

    Decellularized tissues have proven to be versatile matrices for the engineering of tissues and organs. These matrices usually consist of collagens, matrix-specific proteins, and a set of largely undefined growth factors and signaling molecules. Although several decellularized tissues have found their way to clinical applications, their use in the engineering of cartilage tissue has only been explored to a limited extent. We set out to generate hydrogels from several tissue-derived matrices, as hydrogels are the current preferred cell carriers for cartilage repair. Equine cartilage, meniscus, and tendon tissue was harvested, decellularized, enzymatically digested, and functionalized with methacrylamide groups. After photo-cross-linking, these tissue digests were mechanically characterized. Next, gelatin methacrylamide (GelMA) hydrogel was functionalized with these methacrylated tissue digests. Equine chondrocytes and mesenchymal stromal cells (MSCs) (both from three donors) were encapsulated and cultured in vitro up to 6 weeks. Gene expression (COL1A1, COL2A1, ACAN, MMP-3, MMP-13, and MMP-14), cartilage-specific matrix formation, and hydrogel stiffness were analyzed after culture. The cartilage, meniscus, and tendon digests were successfully photo-cross-linked into hydrogels. The addition of the tissue-derived matrices to GelMA affected chondrogenic differentiation of MSCs, although no consequent improvement was demonstrated. For chondrocytes, the tissue-derived matrix gels performed worse compared to GelMA alone. This work demonstrates for the first time that native tissues can be processed into crosslinkable hydrogels for the engineering of tissues. Moreover, the differentiation of encapsulated cells can be influenced in these stable, decellularized matrix hydrogels. PMID:25557049

  6. Everything Achilles: Knowledge Update and Current Concepts in Management: AAOS Exhibit Selection.

    PubMed

    Uquillas, Carlos A; Guss, Michael S; Ryan, Devon J; Jazrawi, Laith M; Strauss, Eric J

    2015-07-15

    Achilles tendon pathology is common and affects athletes and nonathletes alike. The cause is multifactorial and controversial, involving biological, anatomical, and mechanical factors. A variety of conditions characterized by Achilles tendon inflammation and/or degeneration can be clinically and histologically differentiated. These include insertional Achilles tendinopathy, retrocalcaneal bursitis, Achilles paratenonitis, Achilles tendinosis, and Achilles paratenonitis with tendinosis. The mainstay of treatment for all of these diagnoses is nonoperative. There is a large body of evidence addressing treatment of acute and chronic Achilles tendon ruptures; however, controversy remains.

  7. In vivo tissue interaction between the transverse carpal ligament and finger flexor tendons.

    PubMed

    Gabra, Joseph N; Gordon, Joshua L; Marquardt, Tamara L; Li, Zong-Ming

    2016-10-01

    The transverse carpal ligament (TCL) is a component of the flexor pulley system of the wrist, keeping the flexor tendons in place by resisting their volar displacement. The purpose of this study was to investigate the in vivo biomechanical interaction between the TCL and flexor tendons in response to tendon tensioning with the wrist at various postures. In eight healthy subjects, the flexor digitorum superficialis and profundus tendons were tensioned by isometrically applying loads (5, 10, and 15N) to the index finger while the wrist posture was at 20° extension, neutral, 20° flexion, and 40° flexion. The TCL and flexor tendons were imaged at the distal carpal tunnel cross section using ultrasound. The volar-dorsal positions of the tendons, TCL arch height, and TCL-tendon distances were calculated. With increasing wrist flexion, the flexor tendons moved volarly, the TCL arch height increased, and the TCL-tendon distances decreased, indicating that the flexor tendons contacted the TCL and pushed it volarly. The TCL-tendon interaction was amplified by the combination of finger loading and wrist flexion. This study provides in vivo evidence of the biomechanical interaction between the TCL and flexor tendons. Repetitive TCL-tendon interactions may implicate the interacting tissues and the median nerve resulting in tissue maladaptation and nerve compression.

  8. The biological effects of extracorporeal shock wave therapy (eswt) on tendon tissue.

    PubMed

    Notarnicola, Angela; Moretti, Biagio

    2012-01-01

    There is currently great interest in the use of Extracorporeal Shock Wave Therapy (ESWT) and in clarifying the mechanisms of action in tendon pathologies. The success rate ranges from 60% to 80% in epicondylitis, plantar fasciitis, cuff tendinitis, trocanteritis, Achilles tendinitis or jumper's knee. In contrast to urological treatments (lithotripsy), where shockwaves are used to disintegrate renal stones, in musculoskeletal treatments (orthotripsy), shockwaves are not being used to disintegrate tissues, but rather to microscopically cause interstitial and extracellular biological responses and tissue regeneration. The researchers are interesting to investigate the biological effects which support the clinical successes. Some authors speculated that shockwaves relieve pain in insertional tendinopathy by hyper-stimulation analgesia. Many recent studies demonstrated the modulations of shockwave treatment including neovascularization, differentiation of mesenchymal stem cells and local release of angiogenetic factors. The experimental findings confirm that ESWT decrease the expression of high levels of inflammatory mediators (matrix metalloproteinases and inter-leukins). Therefore, ESWT produces a regenerative and tissue-repairing effect in musculoskeletal tissues, not merely a mechanical disintegrative effect as generally before assumed. Based on the encouraging results of clinical and experimental studies, the potential of ESWT appears to be emerging. The promising outcome after this non-invasive treatment option in tendinitis care justifies the indication of shockwave therapy. Further studies have to be performed in order or determine optimum treatment parameters and will bring about an improvement in accordance with evidence-based medicine. Finally, meta-analysis studies are necessary to demonstrate the efficacy and safety of ESWT in treating tendinopathies.

  9. The biological effects of extracorporeal shock wave therapy (eswt) on tendon tissue

    PubMed Central

    Notarnicola, Angela; Moretti, Biagio

    2012-01-01

    Summary There is currently great interest in the use of Extracorporeal Shock Wave Therapy (ESWT) and in clarifying the mechanisms of action in tendon pathologies. The success rate ranges from 60% to 80% in epicondylitis, plantar fasciitis, cuff tendinitis, trocanteritis, Achilles tendinitis or jumper’s knee. In contrast to urological treatments (lithotripsy), where shockwaves are used to disintegrate renal stones, in musculoskeletal treatments (orthotripsy), shockwaves are not being used to disintegrate tissues, but rather to microscopically cause interstitial and extracellular biological responses and tissue regeneration. The researchers are interesting to investigate the biological effects which support the clinical successes. Some authors speculated that shockwaves relieve pain in insertional tendinopathy by hyper-stimulation analgesia. Many recent studies demonstrated the modulations of shockwave treatment including neovascularization, differentiation of mesenchymal stem cells and local release of angiogenetic factors. The experimental findings confirm that ESWT decrease the expression of high levels of inflammatory mediators (matrix metalloproteinases and inter-leukins). Therefore, ESWT produces a regenerative and tissue-repairing effect in musculoskeletal tissues, not merely a mechanical disintegrative effect as generally before assumed. Based on the encouraging results of clinical and experimental studies, the potential of ESWT appears to be emerging. The promising outcome after this non-invasive treatment option in tendinitis care justifies the indication of shockwave therapy. Further studies have to be performed in order or determine optimum treatment parameters and will bring about an improvement in accordance with evidence-based medicine. Finally, meta-analysis studies are necessary to demonstrate the efficacy and safety of ESWT in treating tendinopathies. PMID:23738271

  10. Fluoroquinolone-induced Achilles tendinitis.

    PubMed

    Tam, P K; Ho, Carmen T K

    2014-12-01

    We report a case of Achilles tendinitis after intake of ciprofloxacin for treatment of respiratory tract infection. Fluoroquinolone-induced tendinopathy is an uncommon but increasingly recognised adverse effect of this antibiotic class. Most of the cases occur in the Achilles tendon and may lead to tendon rupture. Possible predisposing risk factors include use of steroid, patients with renal impairment or renal transplant, old age, and being an athlete. The drug should be stopped once this condition is suspected. Symptomatic treatment should be given and orthopaedic referral is desirable if tendon rupture occurs.

  11. p38 MAPK Signaling in Postnatal Tendon Growth and Remodeling

    PubMed Central

    Schwartz, Andrew J.; Sarver, Dylan C.; Sugg, Kristoffer B.; Dzierzawski, Justin T.; Gumucio, Jonathan P.; Mendias, Christopher L.

    2015-01-01

    Tendon is a dynamic tissue whose structure and function is influenced by mechanical loading, but little is known about the fundamental mechanisms that regulate tendon growth and remodeling in vivo. Data from cultured tendon fibroblasts indicated that the p38 MAPK pathway plays an important role in tendon fibroblast proliferation and collagen synthesis in vitro. To gain greater insight into the mechanisms of tendon growth, and explore the role of p38 MAPK signaling in this process, we tested the hypotheses that inducing plantaris tendon growth through the ablation of the synergist Achilles tendon would result in rapid expansion of a neotendon matrix surrounding the original tendon, and that treatment with the p38 MAPK inhibitor SB203580 would prevent this growth. Rats were treated with vehicle or SB203580, and subjected to synergist ablation by bilateral tenectomy of the Achilles tendon. Changes in histological and biochemical properties of plantaris tendons were analyzed 3, 7, or 28 days after overload, and comparisons were made to non-overloaded animals. By 28 days after overload, tendon mass had increased by 30% compared to non-overloaded samples, and cross-sectional area (CSA) increased by around 50%, with most of the change occurring in the neotendon. The expansion in CSA initially occurred through the synthesis of a hyaluronic acid rich matrix that was progressively replaced with mature collagen. Pericytes were present in areas of active tendon growth, but never in the original tendon ECM. Inhibition of p38 MAPK resulted in a profound decrease in IL6 expression, and had a modest effect on the expression of other ECM and cell proliferation genes, but had a negligible impact on overall tendon growth. The combined results from this study provided novel insights into tendon mechanobiology, and suggest that p38 MAPK signaling does not appear to be necessary for tendon growth in vivo. PMID:25768932

  12. Inflammatory and Metabolic Alterations of Kager's Fat Pad in Chronic Achilles Tendinopathy

    PubMed Central

    Fredberg, Ulrich; Kjær, Søren G.; Quistorff, Bjørn; Langberg, Henning; Hansen, Jacob B.

    2015-01-01

    Background Achilles tendinopathy is a painful inflammatory condition characterized by swelling, stiffness and reduced function of the Achilles tendon. Kager’s fat pad is an adipose tissue located in the area anterior to the Achilles tendon. Observations reveal a close physical interplay between Kager’s fat pad and its surrounding structures during movement of the ankle, suggesting that Kager’s fat pad may stabilize and protect the mechanical function of the ankle joint. Aim The aim of this study was to characterize whether Achilles tendinopathy was accompanied by changes in expression of inflammatory markers and metabolic enzymes in Kager’s fat pad. Methods A biopsy was taken from Kager’s fat pad from 31 patients with chronic Achilles tendinopathy and from 13 healthy individuals. Gene expression was measured by reverse transcription-quantitative PCR. Focus was on genes related to inflammation and lipid metabolism. Results Expression of the majority of analyzed inflammatory marker genes was increased in patients with Achilles tendinopathy compared to that in healthy controls. Expression patterns of the patient group were consistent with reduced lipolysis and increased fatty acid β-oxidation. In the fat pad, the pain-signaling neuropeptide substance P was found to be present in one third of the subjects in the Achilles tendinopathy group but in none of the healthy controls. Conclusion Gene expression changes in Achilles tendinopathy patient samples were consistent with Kager’s fat pad being more inflamed than in the healthy control group. Additionally, the results indicate an altered lipid metabolism in Kager’s fat pad of Achilles tendinopathy patients. PMID:25996876

  13. Anterior Cruciate Ligament Reconstruction: Clinical Outcomes of Patella Tendon and Hamstring Tendon Grafts

    PubMed Central

    Gulick, Dawn T.; Yoder, Heather N.

    2002-01-01

    An injury to the ACL can result in significant functional impairment. It has been estimated that more than 100,000 new ACL injuries occur each year. Surgeons employ numerous techniques for reconstruction of the ACL. Of critical importance is the source of the graft to replace the damaged ACL. The graft choices include autografts (the patient's own tissue), allografts (donor tendon), and synthetic/prosthetic ligaments. Tissue harvest sites for autografting include the middle third of the patella tendon, the quadriceps tendon, semitendinosus tendon, gracilis tendon, iliotibial band, tensor fascia lata, and the Achilles tendon. Selection of the type of graft material is predicated upon the tissue's ability to tolerate high levels of stress. Likewise, the clinical presentation and functional outcome is related to the graft material selected. This manuscript specifically examined the patella tendon and hamstring tendon grafts. Numerous manuscripts that studied the outcomes of these graft materials were compiled to help the clinician appreciate the advantages and disadvantages of each of the graft materials. Outcome measures such as thigh circumference, knee range of motion, isokinetic strength, knee stability, pain, and vertical jump/1-leg hop were incorporated. The purpose of this manuscript was to compare and contrast the clinical presentation of patients who underwent an ACL reconstruction using the patella tendon versus the hamstring tendons. This information can be valuable to the clinician when considering the rehabilitation protocol after ACL reconstruction. PMID:24701126

  14. Compromised Neurotrophic and Angiogenic Regenerative Capability during Tendon Healing in a Rat Model of Type-II Diabetes.

    PubMed

    Ahmed, Aisha S; Li, Jian; Abdul, Alim M D; Ahmed, Mahmood; Östenson, Claes-Göran; Salo, Paul T; Hewitt, Carolyn; Hart, David A; Ackermann, Paul W

    2017-01-01

    Metabolic diseases such as diabetes mellitus type-II (DM-II) may increase the risk of suffering painful connective tissue disorders and tendon ruptures. The pathomechanisms, however, by which diabetes adversely affects connective tissue matrix metabolism and regeneration, still need better definition. Our aim was to study the effect of DM-II on expressional changes of neuro- and angiotrophic mediators and receptors in intact and healing Achilles tendon. The right Achilles tendon was transected in 5 male DM-II Goto-Kakizaki (GK) and 4 age-matched Wistar control rats. The left Achilles tendons were left intact. At week 2 post-injury, NGF, BDNF, TSP, and receptors TrkA, TrkB and Nk1 gene expression was studied by quantitative RT-PCR (qRT-PCR) and their protein distribution by immunohistochemistry in intact and injured tendons. The expression of tendon-related markers, Scleraxis (SCX) and Tenomodulin (TNMD), was evaluated by qRT-PCR in intact and injured tendons. Injured tendons of diabetic GK rats exhibited significantly down-regulated Ngf and Tsp1 mRNA and corresponding protein levels, and down-regulated Trka gene expression compared to injured Wistar controls. Intact tendons of DM-II GK rats displayed reduced mRNA levels for Ngf, Tsp1 and Trkb compared to corresponding intact non-diabetic tendons. Up-regulated Scx and Tnmd gene expression was observed in injured tendons of normal and diabetic GK rats compared to intact Wistar controls. However, these molecules were not up-regulated in injured DM-II GK rats compared to their corresponding controls. Our results suggest that DM-II has detrimental effects on neuro- and angiotrophic pathways, and such effects may reflect the compromised repair seen in diabetic Achilles tendon. Thus, novel approaches for regeneration of injured, including tendinopathic, and surgically repaired diabetic tendons may include therapeutic molecular modulation of neurotrophic pathways such as NGF and its receptors.

  15. Compromised Neurotrophic and Angiogenic Regenerative Capability during Tendon Healing in a Rat Model of Type-II Diabetes

    PubMed Central

    Ahmed, Aisha S.; Li, Jian; Abdul, Alim M. D.; Ahmed, Mahmood; Östenson, Claes-Göran; Salo, Paul T.; Hewitt, Carolyn; Hart, David A.; Ackermann, Paul W.

    2017-01-01

    Metabolic diseases such as diabetes mellitus type-II (DM-II) may increase the risk of suffering painful connective tissue disorders and tendon ruptures. The pathomechanisms, however, by which diabetes adversely affects connective tissue matrix metabolism and regeneration, still need better definition. Our aim was to study the effect of DM-II on expressional changes of neuro- and angiotrophic mediators and receptors in intact and healing Achilles tendon. The right Achilles tendon was transected in 5 male DM-II Goto-Kakizaki (GK) and 4 age-matched Wistar control rats. The left Achilles tendons were left intact. At week 2 post-injury, NGF, BDNF, TSP, and receptors TrkA, TrkB and Nk1 gene expression was studied by quantitative RT-PCR (qRT-PCR) and their protein distribution by immunohistochemistry in intact and injured tendons. The expression of tendon-related markers, Scleraxis (SCX) and Tenomodulin (TNMD), was evaluated by qRT-PCR in intact and injured tendons. Injured tendons of diabetic GK rats exhibited significantly down-regulated Ngf and Tsp1 mRNA and corresponding protein levels, and down-regulated Trka gene expression compared to injured Wistar controls. Intact tendons of DM-II GK rats displayed reduced mRNA levels for Ngf, Tsp1 and Trkb compared to corresponding intact non-diabetic tendons. Up-regulated Scx and Tnmd gene expression was observed in injured tendons of normal and diabetic GK rats compared to intact Wistar controls. However, these molecules were not up-regulated in injured DM-II GK rats compared to their corresponding controls. Our results suggest that DM-II has detrimental effects on neuro- and angiotrophic pathways, and such effects may reflect the compromised repair seen in diabetic Achilles tendon. Thus, novel approaches for regeneration of injured, including tendinopathic, and surgically repaired diabetic tendons may include therapeutic molecular modulation of neurotrophic pathways such as NGF and its receptors. PMID:28122008

  16. Ten weeks of treadmill running decreases stiffness and increases collagen turnover in tendons of old mice.

    PubMed

    Wood, Lauren K; Brooks, Susan V

    2016-02-01

    Increased tendon stiffness in response to mechanical loading is well established in young animals. Given that tendons stiffen with aging, we aimed to determine the effect of increased loading on tendons of old animals. We subjected 28-month-old mice to 10 weeks of uphill treadmill running; sedentary 8- and 28-month-old mice served as controls. Following training, plantaris tendon stiffness and modulus were reduced by approximately half, such that the values were not different from those of tendons from adult sedentary animals. The decrease in plantaris tendon stiffness was accompanied by a similar reduction in the levels of advanced glycation end-product protein adducts in tibialis anterior tendons of trained compared with sedentary old mice. In Achilles tendons, elevated mRNA levels for collagen type 1, matrix-metalloproteinase-8, and lysyl oxidase following training suggest that collagen turnover was likely also increased. The dramatic mechanical and structural changes induced by training occurred independent of changes in cell density or tendon morphology. Finally, Achilles tendon calcification was significantly reduced following exercise. These results demonstrate that, in response to exercise, tendons from old animals are capable of replacing damaged and dysfunctional components of extracellular matrix with tissue that is mechanically and structurally comparable to adult tissue.

  17. Achilles Impingement Tendinopathy on Magnetic Resonance Imaging.

    PubMed

    Bullock, Mark J; Mourelatos, Jan; Mar, Alice

    2017-02-28

    Haglund's syndrome is impingement of the retrocalcaneal bursa and Achilles tendon caused by a prominence of the posterosuperior calcaneus. Radiographic measurements are not sensitive or specific for diagnosing Haglund's deformity. Localization of a bone deformity and tendinopathy in the same sagittal section of a magnetic resonance imaging scan can assist with the diagnosis in equivocal cases. The aim of the present cross-sectional study was to determine the prevalence of Haglund's syndrome in patients presenting with Achilles tendinopathy and note any associated findings to determine the criteria for a diagnosis of Haglund's syndrome. We reviewed 40 magnetic resonance imaging scans with Achilles tendinopathy and 19 magnetic resonance imaging scans with Achilles high-grade tears and/or ruptures. Achilles tendinopathy was often in close proximity to the superior aspect of the calcaneal tuberosity, consistent with impingement (67.5%). Patients with Achilles impingement tendinopathy were more often female (p < .04) and were significantly heavier than patients presenting with noninsertional Achilles tendinopathy (p = .014) or Achilles tendon rupture (p = .010). Impingement tendinopathy occurred medially (8 of 20) and centrally (10 of 20) more often than laterally (2 of 20) and was associated with a posterior prominence or hyperconvexity with a loss of calcaneal recess more often than a superior projection (22 of 27 versus 8 of 27; p < .001). Haglund's deformity should be reserved for defining a posterior prominence or hyperconvexity with loss of calcaneal recess because this corresponds with impingement. Achilles impingement tendinopathy might be more appropriate terminology for Haglund's syndrome, because the bone deformity is often subtle. Of the 27 images with Achilles impingement tendinopathy, 10 (37.0%) extended to a location prone to Achilles tendon rupture. Given these findings, insertional and noninsertional Achilles tendinopathy are not mutually

  18. In vitro investigation of a tissue-engineered cell-tendon complex mimicking the transitional architecture at the ligament-bone interface.

    PubMed

    Wang, Zhibing; Zhang, Yuan; Zhu, Jie; Dong, Shiwu; Jiang, Tao; Zhou, Yue; Zhang, Xia

    2015-03-01

    Restoration of the transitional ligament-bone interface is critical for graft-bone integration. We postulated that an allogenic scaffold mimicking the fibrogenic, chondrogenic, and osteogenic transition gradients could physiologically promote ligament-bone incorporation. The aim of this study was to construct and characterize a composite tendon scaffold with a continuous and heterogeneous transition region mimicking a native ligament insertion site. Genetically modified heterogeneous cell populations were seeded within specific regions of decellularized rabbit Achilles tendons to fabricate a stratified scaffold containing three biofunctional regions supporting fibrogenesis, chondrogenesis, and osteogenesis. The observed morphology, architecture, cytocompatibility, and biomechanics of the scaffolds demonstrated their improved bio-physico-chemical properties. The formation of the transitional regions was augmented via enhanced delivery of two transcription factors, sex determining region Y-box 9 and runt-related transcription factor 2, which also triggered early up-regulated expression of cartilage- and bone-relevant markers, according to quantitative PCR and immunoblot analyses. Gradient tissue-specific matrix formation was also confirmed within the predesignated regions via histological staining and immunofluorescence assays. These results suggest that a transitional interface could be replicated on an engineered tendon through stratified tissue integration. The scaffold offers the advantages of a multitissue transition involving controlled cellular interactions and matrix heterogeneity, which can be applied for the regeneration of the ligament-bone interface.

  19. Tendon progenitor cells in injured tendons have strong chondrogenic potential: the CD105-negative subpopulation induces chondrogenic degeneration.

    PubMed

    Asai, Shuji; Otsuru, Satoru; Candela, Maria Elena; Cantley, Leslie; Uchibe, Kenta; Hofmann, Ted J; Zhang, Kairui; Wapner, Keith L; Soslowsky, Louis J; Horwitz, Edwin M; Enomoto-Iwamoto, Motomi

    2014-12-01

    To study the cellular mechanism of the tendon repair process, we used a mouse Achilles tendon injury model to focus on the cells recruited to the injured site. The cells isolated from injured tendon 1 week after the surgery and uninjured tendons contained the connective tissue progenitor populations as determined by colony-forming capacity, cell surface markers, and multipotency. When the injured tendon-derived progenitor cells (inTPCs) were transplanted into injured Achilles tendons, they were not only integrated in the regenerating area expressing tenogenic phenotype but also trans-differentiated into chondrogenic cells in the degenerative lesion that underwent ectopic endochondral ossification. Surprisingly, the micromass culture of the inTPCs rapidly underwent chondrogenic differentiation even in the absence of exogenous bone morphogenetic proteins or TGFβs. The cells isolated from human ruptured tendon tissues also showed connective tissue progenitor properties and exhibited stronger chondrogenic ability than bone marrow stromal cells. The mouse inTPCs contained two subpopulations one positive and one negative for CD105, a coreceptor of the TGFβ superfamily. The CD105-negative cells showed superior chondrogenic potential in vitro and induced larger chondroid degenerative lesions in mice as compared to the CD105-positive cells. These findings indicate that tendon progenitor cells are recruited to the injured site of tendons and have a strong chondrogenic potential and that the CD105-negative population of these cells would be the cause for chondroid degeneration in injured tendons. The newly identified cells recruited to the injured tendon may provide novel targets to develop therapeutic strategies to facilitate tendon repair.

  20. Endoscopic Calcaneoplasty and Achilles Tendoscopy With the Patient in Supine Position.

    PubMed

    Lui, Tun Hing

    2016-12-01

    Insertional and non-insertional Achilles tendinopathy is usually treated conservatively. Surgery is indicated if conservative treatment fails to relieve the pain. Endoscopic surgery has the advantages of less morbidity, a shorter operating time, reduced postoperative pain, and a lower rate of wound and soft-tissue healing problems. Patients will have a short recovery time and quickly resume work and sports because of less soft-tissue disruption. Moreover, the pathology can be better differentiated and precisely treated. Achilles tendoscopy is classically performed with the patient in the prone position, whereas endoscopic calcaneoplasty can be performed with the patient in the prone or supine position. This technical note describes the technique of Achilles tendoscopy and endoscopic calcaneoplasty with the patient in the supine position. This has the advantages of more ergonomic hand motion for the Achilles tendon debridement, easier access to the ventral surface of the Achilles tendon, and better orientation of the inside structures; moreover, concomitant chondral lesions of the ankle can be dealt with arthroscopically.

  1. 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

  2. Tendon tissue engineering and gene transfer: the future of surgical treatment.

    PubMed

    Huang, Deqing; Balian, Gary; Chhabra, A Bobby

    2006-01-01

    Technologic improvements in the field of tissue engineering are leading to new potential developments in the currently used approaches to treat tendon injuries including difficult clinical scenarios such as zone II flexor tendon injuries of the hand and the mutilated hand with extensive tendon defects. A combination of mesenchymal (adult stem) cells, growth factors, and bioresorbable polymers can provide a solution for the treatment of difficult tendon injuries. Extensive research is needed to show that the extracellular matrix produced in response to the cell/growth factor/polymer composites in vivo is effective and functional as a regenerate tissue. Further exciting advances are foreseen in cell-based genetic engineering with the transfer of DNA to the site of tendon lacerations. These treatment modalities require improved safety precautions to reduce the risks and enhance the benefits of gene therapy.

  3. Management of chronic Achilles tendinopathy.

    PubMed

    2012-08-01

    Tendons transmit force between muscles and bones and, when stretched, store elastic energy that contributes to movement.(1) The tendinous portion of the gastrocnemius and soleus muscles merge to form the Achilles tendon, which is the largest and strongest in the body, but one of the most frequently injured.(2,3) Conservative management options for chronic Achilles tendinopathy include eccentric (lengthening) exercises, extracorporeal shockwave therapy (ESWT), topical nitroglycerin, low level laser therapy, orthoses, splints or injections (e.g. corticosteroids, hyperosmolar dextrose, polidocanol, platelet-rich plasma), while a minority of patients require surgery (using open, percutaneous or endoscopic methods).(4-8) Here we assess the management options for patients with chronic Achilles tendinopathy (lasting over 6 weeks).

  4. Tenocyte contraction induces crimp formation in tendon-like tissue

    PubMed Central

    Holmes, David F.; Hill, Patrick; Kadler, Karl E.; Margetts, Lee

    2013-01-01

    Tendons are composed of longitudinally aligned collagen fibrils arranged in bundles with an undulating pattern, called crimp. The crimp structure is established during embryonic development and plays a vital role in the mechanical behaviour of tendon, acting as a shock absorber during loading. However, the mechanism of crimp formation is unknown, partly because of the difficulties of studying tendon development in vivo. Here we used a 3D cell culture system in which embryonic tendon fibroblasts synthesize a tendon-like construct comprised of collagen fibrils arranged in parallel bundles. Investigations using polarized light microscopy, scanning electron microscopy and fluorescence microscopy showed that tendon-constructs contained a regular pattern of wavy collagen fibrils. Tensile testing indicated that this superstructure was a form of embryonic crimp producing a characteristic toe region in the stress-strain curves. Furthermore, contraction of tendon fibroblasts was the critical factor in the buckling of collagen fibrils during the formation of the crimp structure. Using these biological data, a finite element model was built that mimics the contraction of the tendon fibroblasts and monitors the response of the ECM. The results show that the contraction of the fibroblasts is a sufficient mechanical impulse to build a planar wavy pattern. Furthermore, the value of crimp wavelength was determined by the mechanical properties of the collagen fibrils and inter-fibrillar matrix. Increasing fibril stiffness combined with constant matrix stiffness led to an increase in crimp wavelength. The data suggest a novel mechanism of crimp formation, and the finite element model indicates the minimum requirements to generate a crimp structure in embryonic tendon. PMID:21735243

  5. Tenocyte contraction induces crimp formation in tendon-like tissue.

    PubMed

    Herchenhan, Andreas; Kalson, Nicholas S; Holmes, David F; Hill, Patrick; Kadler, Karl E; Margetts, Lee

    2012-03-01

    Tendons are composed of longitudinally aligned collagen fibrils arranged in bundles with an undulating pattern, called crimp. The crimp structure is established during embryonic development and plays a vital role in the mechanical behaviour of tendon, acting as a shock-absorber during loading. However, the mechanism of crimp formation is unknown, partly because of the difficulties of studying tendon development in vivo. Here, we used a 3D cell culture system in which embryonic tendon fibroblasts synthesise a tendon-like construct comprised of collagen fibrils arranged in parallel bundles. Investigations using polarised light microscopy, scanning electron microscopy and fluorescence microscopy showed that tendon constructs contained a regular pattern of wavy collagen fibrils. Tensile testing indicated that this superstructure was a form of embryonic crimp producing a characteristic toe region in the stress-strain curves. Furthermore, contraction of tendon fibroblasts was the critical factor in the buckling of collagen fibrils during the formation of the crimp structure. Using these biological data, a finite element model was built that mimics the contraction of the tendon fibroblasts and monitors the response of the Extracellular matrix. The results show that the contraction of the fibroblasts is a sufficient mechanical impulse to build a planar wavy pattern. Furthermore, the value of crimp wavelength was determined by the mechanical properties of the collagen fibrils and inter-fibrillar matrix. Increasing fibril stiffness combined with constant matrix stiffness led to an increase in crimp wavelength. The data suggest a novel mechanism of crimp formation, and the finite element model indicates the minimum requirements to generate a crimp structure in embryonic tendon.

  6. Incidence of Major Tendon Ruptures and Anterior Cruciate Ligament Tears in US Army Soldiers

    DTIC Science & Technology

    2007-08-01

    patellar tendon [PT], and Achilles tendon [AT]) has increased in recent decades presumably because of increased recreational sports activity in our...1995 and 1996 were identified and evaluated for risk factors. Results: The authors identified 52 major tendon ruptures: 29 Achilles, 12 patellar , 7... patellar tendon rupture; Achilles tendon rupture; race; mechanism of injury *Address correspondence to LTC Daniel W. White, MD, 1 Jarrett White Road

  7. 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.

  8. Achilles Tendinitis.

    PubMed

    Eickler, Richard; Pomeranz, Stephen J

    2015-01-01

    Achilles tendinitis is a common etiology of heel pain, which is a common patient complaint. Achilles tendinitis can be classified into noninsertional tendinosis and insertional tendinitis on the basis of clinical features, radiologic signs, and pathologic findings. Magnetic resonance imaging (MRI) allows classification and reveals associated findings, including retrocalcaneal bursitis, paratendinitis, and paratenonitis. Furthermore, MRI may not only confirm findings of Achilles tendinitis but also diagnose other etiologies of heel pain. This article reviews the MRI findings and terminology of Achilles tendinitis often found in radiology reports.

  9. Fixation of tendo Achilles avulsion fracture.

    PubMed

    Lui, T H

    2009-01-01

    Achilles tendon ruptures occur commonly in the midsubstance of the tendon, usually 2-6 cm proximal to the insertion to the calcaneus. Ruptures near its insertion into the calcaneus are less common and mostly found in hyperpronators with a heel spur (Haglund's deformity). Avulsion of the bony insertion of the Achilles tendon at the calcaneus is infrequent and is diagnosed by radiography. Open reduction and internal fixation is indicated to achieve bone to bone healing and restoration of the function and continuity of the triceps surae mechanism. Screw fixation is not effective to resist the pull out tension of the triceps surae. Moreover, the prominent screw head may cause skin impingement. More secure fixation method is necessary in order to allow early functional rehabilitation. We describe a technique to fix the avulsed fragment of Achilles tendon insertion with 2 suture anchors. This can neutralize the pull of the triceps surae and early post-operative rehabilitation programme is allowed.

  10. Application of stem cells derived from the periodontal ligament or gingival tissue sources for tendon tissue regeneration.

    PubMed

    Moshaverinia, Alireza; Xu, Xingtian; Chen, Chider; Ansari, Sahar; Zadeh, Homayoun H; Snead, Malcolm L; Shi, Songtao

    2014-03-01

    Tendon injuries are often associated with significant dysfunction and disability due to tendinous tissue's very limited self-repair capacity and propensity for scar formation. Dental-derived mesenchymal stem cells (MSCs) in combination with appropriate scaffold material present an alternative therapeutic option for tendon repair/regeneration that may be advantageous compared to other current treatment modalities. The MSC delivery vehicle is the principal determinant for successful implementation of MSC-mediated regenerative therapies. In the current study, a co-delivery system based on TGF-β3-loaded RGD-coupled alginate microspheres was developed for encapsulating periodontal ligament stem cells (PDLSCs) or gingival mesenchymal stem cells (GMSCs). The capacity of encapsulated dental MSCs to differentiate into tendon tissue was investigated in vitro and in vivo. Encapsulated dental-derived MSCs were transplanted subcutaneously into immunocompromised mice. Our results revealed that after 4 weeks of differentiation in vitro, PDLSCs and GMSCs as well as the positive control human bone marrow mesenchymal stem cells (hBMMSCs) exhibited high levels of mRNA expression for gene markers related to tendon regeneration (Scx, DCn, Tnmd, and Bgy) via qPCR measurement. In a corresponding in vivo animal model, ectopic neo-tendon regeneration was observed in subcutaneous transplanted MSC-alginate constructs, as confirmed by histological and immunohistochemical staining for protein markers specific for tendons. Interestingly, in our quantitative PCR and in vivo histomorphometric analyses, PDLSCs showed significantly greater capacity for tendon regeneration than GMSCs or hBMMSCs (P < 0.05). Altogether, these findings indicate that periodontal ligament and gingival tissues can be considered as suitable stem cell sources for tendon engineering. PDLSCs and GMSCs encapsulated in TGF-β3-loaded RGD-modified alginate microspheres are promising candidates for tendon regeneration.

  11. Assessment of stem cell carriers for tendon tissue engineering in pre-clinical models

    PubMed Central

    2014-01-01

    Tendon injuries are prevalent and problematic, especially among young and otherwise healthy individuals. The inherently slow innate healing process combined with the inevitable scar tissue formation compromise functional recovery, imposing the need for the development of therapeutic strategies. The limited number of low activity/reparative capacity tendon-resident cells has directed substantial research efforts towards the exploration of the therapeutic potential of various stem cells in tendon injuries and pathophysiologies. Severe injuries require the use of a stem cell carrier to enable cell localisation at the defect site. The present study describes advancements that injectable carriers, tissue grafts, anisotropically orientated biomaterials, and cell-sheets have achieved in preclinical models as stem cell carriers for tendon repair. PMID:25157898

  12. Application of stem cells derived from the periodontal ligament or gingival tissue sources for tendon tissue regeneration

    PubMed Central

    Moshaverinia, Alireza; Xu, Xingtian; Chen, Chider; Ansari, Sahar; Zadeh, Homayoun H.; Snead, Malcolm L.; Shi, Songtao

    2014-01-01

    Tendon injuries are often associated with significant dysfunction and disability due to tendinous tissue’s very limited self-repair capacity and propensity for scar formation. Dental-derived mesenchymal stem cells (MSCs) in combination with appropriate scaffold material present an alternative therapeutic option for tendon repair/regeneration that may be advantageous compared to other current treatment modalities. The MSC delivery vehicle is the principal determinant for successful implementation of MSC-mediated regenerative therapies. In the current study, a co-delivery system based on TGF-β3-loaded RGD-coupled alginate microspheres was developed for encapsulating periodontal ligament stem cells (PDLSCs) or gingival mesenchymal stem cells (GMSCs). The capacity of encapsulated dental MSCs to differentiate into tendon tissue was investigated in vitro and in vivo. Encapsulated dental-derived MSCs were transplanted subcutaneously into immunocompromised mice. Our results revealed that after 4 weeks of differentiation in vitro, PDLSCs and GMSCs as well as the positive control human bone marrow mesenchymal stem cells (hBMMSCs) exhibited high levels of mRNA expression for gene markers related to tendon regeneration (Scx, DCn, Tnmd, and Bgy) via qPCR measurement. In a corresponding in vivo animal model, ectopic neo-tendon regeneration was observed in subcutaneous transplanted MSC-alginate constructs, as confirmed by histological and immunohistochemical staining for protein markers specific for tendons. Interestingly, in our quantitative PCR and in vivo histomorphometric analyses, PDLSCs showed significantly greater capacity for tendon regeneration than GMSCs or hBMMSCs (P<0.05). Altogether, these findings indicate that periodontal ligament and gingival tissues can be considered as suitable stem cell sources for tendon engineering. PDLSCs and GMSCs encapsulated in TGF-β3-loaded RGD-modified alginate microspheres are promising candidates for tendon regeneration. PMID

  13. Achilles tendinitis in ballet dancers.

    PubMed

    Fernández-Palazzi, F; Rivas, S; Mujica, P

    1990-08-01

    Overuse injuries of tendons are known to occur in persons whose activities submit the tendon to excessive stress. Classical ballet dancers performing en pointe, demie point, or plié exert forces that, although normal in magnitude, are increased in frequency, thus overusing the Achilles tendon. In the present study all cases of Achilles tendinopathy seen in a period of three years in three ballet companies were reviewed by a special orthopedic clinic. The cause, whether by abnormal tension or incorrect use, development, and progression to chronic tendinopathy, as well as measures to prevent it, were analyzed in 19 cases. The methods of treatment, including conservative treatment with rest and refraining from dancing, local treatment such as ice and adhesive strapping, antiinflammatory drugs, local injections, thermotherapy, and laser therapy, were compared, and the time of recovery and ability to resume dancing were evaluated. Two cases required surgical treatment to subside, and the patients had to retire from professional dancing. The roentgenographic diagnosis of stage and progression of the tendinopathy is emphasized as a valuable accessory sign. The similarity in lesions between Achilles and patellar tendon problems was observed and confirmed.

  14. Direct E-jet printing of three-dimensional fibrous scaffold for tendon tissue engineering.

    PubMed

    Wu, Yang; Wang, Zuyong; Ying Hsi Fuh, Jerry; San Wong, Yoke; Wang, Wilson; San Thian, Eng

    2017-04-01

    Tissue engineering (TE) offers a promising strategy to restore diseased tendon tissue. However, a suitable scaffold for tendon TE has not been achieved with current fabrication techniques. Herein, we report the development of a novel electrohydrodynamic jet printing (E-jetting) for engineering 3D tendon scaffold with high porosity and orientated micrometer-size fibers. The E-jetted scaffold comprised tubular multilayered micrometer-size fibrous bundles, with interconnected spacing and geometric anisotropy along the longitudinal direction of the scaffold. Fiber diameter, stacking pattern, and interfiber distance have been observed to affect the structural stability of the scaffold, of which the enhanced mechanical strength can be obtained for scaffolds with thick fibers as the supporting layer. Human tenocytes showed a significant increase in cellular metabolism on the E-jetted scaffolds as compared to that on conventional electrospun scaffolds (2.7-, 2.8-, and 3.1-fold increase for 150, 300, and 600 µm interfiber distance, respectively; p < 0.05). Furthermore, the scaffolds provided structural support for human tenocytes to align with controlled orientation along the longitudinal direction of the scaffold, and promoted the expression of collagen type I. For the first time, E-jetting has been explored as a novel scaffolding approach for tendon TE, and offers a 3D fibrous scaffold to promote organized tissue reconstruction for potential tendon healing. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 616-627, 2017.

  15. Repair of Chronic Achilles Ruptures Has a High Incidence of Venous Thromboembolism.

    PubMed

    Bullock, Mark J; DeCarbo, William T; Hofbauer, Mark H; Thun, Joshua D

    2016-11-23

    Background Despite the low incidence of deep vein thrombosis (DVT) in foot and ankle surgery, some authors report a high incidence of symptomatic DVT following Achilles tendon rupture. The purpose of this study was to identify DVT risk factors inherent to Achilles tendon repair to determine which patients may benefit from prophylaxis. Methods One hundred and thirteen patient charts were reviewed following elective and nonelective Achilles tendon repair. For elective repair of insertional or noninsertional Achilles tendinopathy, parameters examined included lateral versus prone positioning and the presence versus absence of a flexor hallucis longus transfer. For nonelective repair, acute Achilles tendon ruptures were compared to chronic Achilles tendon ruptures. Results Of 113 Achilles tendon repairs, 3 venous thromboembolism (VTE) events (2.65%) occurred including 2 pulmonary emboli (1.77%). Seventeen of these repairs were chronic Achilles tendon ruptures, and all 3 VTE events (17.6%) occurred within this subgroup. Elevated body mass index was associated with VTE in patients with chronic Achilles ruptures although this did not reach significance (P = .064). No VTE events were reported after repair of 28 acute tendon ruptures or after 68 elective repairs of tendinopathy. Two patients with misdiagnosed partial Achilles tendon tears were excluded because they experienced a VTE event 3 weeks and 5 weeks after injury, prior to surgery. Conclusion In our retrospective review, chronic Achilles ruptures had a statistically significant higher incidence of VTE compared with acute Achilles ruptures (P = .048) or elective repair (P = .0069). Pharmaceutical anticoagulation may be considered for repair of chronic ruptures. Repair of acute ruptures and elective repair may not warrant routine prophylaxis due to a lower incidence of VTE.

  16. Achilles tendinitis

    MedlinePlus

    Tendinitis of the heel ... foot. Rarely, it is caused by an injury. Tendinitis due to overuse is most common in younger ... occur in walkers, runners, or other athletes. Achilles tendinitis may be more likely to occur if: There ...

  17. Development and evaluation of a removable tissue-engineered muscle with artificial tendons.

    PubMed

    Nakamura, Tomohiro; Takagi, Shunya; Kamon, Takafumi; Yamasaki, Ken-Ichi; Fujisato, Toshia

    2017-02-01

    Tissue-engineered skeletal muscles were potentially useful as physiological and biochemical in vitro models. Currently, most of the similar models were constructed without tendons. In this study, we aimed to develop a simple, highly versatile tissue-engineered muscle with artificial tendons, and to evaluate the contractile, histological and molecular dynamics during differentiation. C2C12 cells were embedded in a cold type-І collagen gel and placed between two artificial tendons on a silicone sheet. The construct shrank and tightly attached to the artificial tendons with differentiation, finally detaching from the silicone sheet within 1 week of culture onset. We successfully developed a tissue-engineered skeletal muscle with two artificial tendons from C2C12 myoblasts embedded in type-І collagen gel. The isometric twitch contractile force (TCF) significantly increased during differentiation. Time to Peak Tension (TPT) and Half-Relaxation Time (1/2RT) were significantly shortened during differentiation. Myogenic regulatory factors were maximally expressed at 2 weeks, and subsequently decreased at 3 weeks of culture. Histological analysis indicated that myotube formation increased markedly from 2 weeks and well-ordered sarcomere structures were observed on the surface of the 3D engineered muscle at 3 weeks of culture. These results suggested that robust muscle structure occurred by 3 weeks in the tissue-engineered skeletal muscle. Moreover, during the developmental process, the artificial tendons might contribute to well-ordered sarcomere formation. Our results indicated that this simple culture system could be used to evaluate the effects of various pharmacological and mechanical cues on muscle contractility in a variety of research areas.

  18. Infectious Achilles Tendinitis After Local Injection of Human Placental Extracts: A Case Report.

    PubMed

    Kim, Yoon-Chung; Ahn, Jae Hoon; Kim, Man-Soo

    2015-01-01

    Local injections of corticosteroids or human placental extracts are sometimes used for the treatment of resistant tendinitis or fasciitis. We report a case of infectious Achilles tendinitis complicated by calcaneal osteomyelitis after injection of human placental extracts for the Achilles tendinitis. She was treated with excision of the infected bone and tendon, followed by V-Y lengthening of the proximal portion of the Achilles tendon in a single stage. At 2 years postoperative, she remained symptom free without any signs of recurrence, and the follow-up magnetic resonance imaging scan demonstrated a well-maintained Achilles tendon with normal signal intensity.

  19. HGF mediates the anti-inflammatory effects of PRP on injured tendons.

    PubMed

    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.

  20. Production of PGE(2) increases in tendons subjected to repetitive mechanical loading and induces differentiation of tendon stem cells into non-tenocytes.

    PubMed

    Zhang, Jianying; Wang, James H-C

    2010-02-01

    Whether tendon inflammation is involved in the development of tendinopathy or degenerative changes of the tendon remains a matter of debate. We explored this question by performing animal and cell culture experiments to determine the production and effects of PGE(2), a major inflammatory mediator in tendons. Mouse tendons were subjected to repetitive mechanical loading via treadmill running, and the effect of PGE(2) on proliferation and differentiation of tendon stem cells (TSCs) was assessed in vitro. Compared to levels in cage control mice, PGE(2) levels in mouse patellar and Achilles tendons were markedly increased in response to a bout of rigorous treadmill running. PGE(2) treatment of TSCs in culture decreased cell proliferation and induced both adipogenesis and osteogenesis of TSCs, as evidenced by accumulation of lipid droplets and calcium deposits, respectively. Effects of PGE(2) on both TSC proliferation and differentiation were apparently PGE(2)-dose-dependent. These findings suggest that high levels of PGE(2), which are present in tendons subjected to repetitive mechanical loading conditions in vivo as shown in this study, may result in degenerative changes of the tendon by decreasing proliferation of TSCs in tendons and also inducing differentiation of TSCs into adipocytes and osteocytes. The consequences of this PGE(2) effect on TSCs is the reduction of the pool of tenocytes for repair of tendons injured by mechanical loading, and production of fatty and calcified tissues within the tendon, often seen at the later stages of tendinopathy.

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

    SciTech Connect

    Zhang, Kairui; Zhang, Sheng; Li, Qianqian; Yang, Jun; Dong, Weiqiang; Wang, Shengnan; Cheng, Yirong; Al-Qwbani, Mohammed; Wang, Qiang; Yu, Bin

    2014-07-18

    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 aims 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.

  2. Multiscale Poly-(ϵ-caprolactone) Scaffold Mimicking Nonlinearity in Tendon Tissue Mechanics

    PubMed Central

    Banik, Brittany L.; Lewis, Gregory S.; Brown, Justin L.

    2016-01-01

    Regenerative medicine plays a critical role in the future of medicine. However, challenges remain to balance stem cells, biomaterial scaffolds, and biochemical factors to create successful and effective scaffold designs. This project analyzes scaffold architecture with respect to mechanical capability and preliminary mesenchymal stem cell response for tendon regeneration. An electrospun fiber scaffold with tailorable properties based on a “Chinese-fingertrap” design is presented. The unique criss-crossed fiber structures demonstrate non-linear mechanical response similar to that observed in native tendon. Mechanical testing revealed that optimizing the fiber orientation resulted in the characteristic “S”-shaped curve, demonstrating a toe region and linear elastic region. This project has promising research potential across various disciplines: vascular engineering, nerve regeneration, and ligament and tendon tissue engineering. PMID:27141530

  3. Micropatterning of nanocomposite polymer scaffolds using sacrificial phosphate glass fibers for tendon tissue engineering applications.

    PubMed

    Alshomer, Feras; Chaves, Camilo; Serra, Tiziano; Ahmed, Ifty; Kalaskar, Deepak M

    2017-01-20

    This study presents a simple and reproducible method of micropatterning the novel nanocomposite polymer (POSS-PCU) using a sacrificial phosphate glass fiber template for tendon tissue engineering applications. The diameters of the patterned scaffolds produced were dependent on the diameter of the glass fibers (15 μm) used. Scaffolds were tested for their physical properties and reproducibility using various microscopy techniques. For the first time, we show that POSS-PCU supports growth of human tenocytes cells. Furthermore, we show that cellular alignment, their biological function and expression of various tendon related proteins such as scleraxis, collagen I and III, tenascin-C are significantly elevated on the micropatterned polymer surfaces compared to flat samples. This study demonstrated a simple, reproducible method of micropatterning POSS-PCU nanocomposite polymer for novel tendon repair applications, which when provided with physical cues could help mimic the microenvironment of tenocytes cells.

  4. Measurement of tendon velocities using vector tissue Doppler imaging: a feasibility study.

    PubMed

    Eranki, Avinash; Bellini, Lindsey; Prosser, Laura; Stanley, Christopher; Bland, Daniel; Alter, Katharine; Damiano, Diane; Sikdar, Siddhartha

    2010-01-01

    We have developed a vector Doppler ultrasound imaging method to directly quantify the magnitude and direction of muscle and tendon velocities during movement. The goal of this study was to evaluate the feasibility of using vector Tissue Doppler Imaging (vTDI) for estimating the tibialis anterior tendon velocities during dorsiflexion in children with cerebral palsy who have foot drop. Our preliminary results from this study show that tendon velocities estimated using vTDI have a strong linear correlation with the joint angular velocity estimated using a conventional 3D motion capture system. We observed a peak tendon velocity of 5.66±1.45 cm/s during dorsiflexion and a peak velocity of 8.83±2.13 cm/s during the passive relaxation phase of movement. We also obtained repeatable results from the same subject 3 weeks apart. Direct measurements of muscle and tendon velocities may be used as clinical outcome measures and for studying efficiency of movement control.

  5. The effects of dynamic stretching on plantar flexor muscle-tendon tissue properties.

    PubMed

    Samukawa, Mina; Hattori, Masaki; Sugama, Naoko; Takeda, Naoki

    2011-12-01

    Dynamic stretching is commonly used in warm-up routines for athletic activities. Even though several positive effects of dynamic stretching on athletic performance have been reported, the effects on the muscle-tendon unit (MTU) itself are still unclear. The objective of this study is to determine the effects of dynamic stretching on the ankle plantar flexor muscle-tendon properties by use of ultrasonography. Twenty healthy male subjects participated in the present study. The subjects were asked to engage in dynamic stretching of plantar flexors for 30 s and to repeat for 5 sets. Ankle dorsiflexion ROM was measured before and after the dynamic stretching. Changes in the displacement of the myotendinous junction (MTJ), pennation angle, and fascicle length were also determined by using ultrasonography. Ankle dorsiflexion ROM increased significantly after the dynamic stretching (p < 0.0001). A significant distal displacement of the MTJ was observed until the second stretching set (p < 0.001) with no significant changes thereafter. Pennation angle, and fascicle length were unaffected by the dynamic stretching. Dynamic stretching was shown to be effective in increasing ankle joint flexibility. Outcomes that could have indicated changes in muscle tissue (such as the pennation angle and fascicle length) were unaltered. However, a significant displacement of the MTJ was found, indicating some change in the tendon tissues. Therefore, dynamic stretching of the plantar flexors was considered an effective means of lengthening the tendon tissues.

  6. Controlled Bioactive Molecules Delivery Strategies for Tendon and Ligament Tissue Engineering using Polymeric Nanofibers.

    PubMed

    Hiong Teh, Thomas Kok; Hong Goh, James Cho; Toh, Siew Lok

    2015-01-01

    The interest in polymeric nanofibers has escalated over the past decade given its promise as tissue engineering scaffolds that can mimic the nanoscale structure of the native extracellular matrix. With functionalization of the polymeric nanofibers using bioactive molecules, localized signaling moieties can be established for the attached cells, to stimulate desired biological effects and direct cellular or tissue response. The inherently high surface area per unit mass of polymeric nanofibers can enhance cell adhesion, bioactive molecules loading and release efficiencies, and mass transfer properties. In this review article, the application of polymeric nanofibers for controlled bioactive molecules delivery will be discussed, with a focus on tendon and ligament tissue engineering. Various polymeric materials of different mechanical and degradation properties will be presented along with the nanofiber fabrication techniques explored. The bioactive molecules of interest for tendon and ligament tissue engineering, including growth factors and small molecules, will also be reviewed and compared in terms of their nanofiber incorporation strategies and release profiles. This article will also highlight and compare various innovative strategies to control the release of bioactive molecules spatiotemporally and explore an emerging tissue engineering strategy involving controlled multiple bioactive molecules sequential release. Finally, the review article concludes with challenges and future trends in the innovation and development of bioactive molecules delivery using polymeric nanofibers for tendon and ligament tissue engineering.

  7. Elastographic characteristics of the metacarpal tendons in horses without clinical evidence of tendon injury.

    PubMed

    Lustgarten, Meghann; Redding, W Rich; Labens, Raphael; Morgan, Michel; Davis, Weston; Seiler, Gabriela S

    2014-01-01

    Tendon and ligament injuries are common causes of impaired performance in equine athletes. Gray-scale ultrasonography is the current standard method for diagnosing and monitoring these injuries, however this modality only provides morphologic information. Elastography is an ultrasound technique that allows detection and measurement of tissue strain, and may provide valuable mechanical information about equine tendon and ligament injuries. The purpose of this study was to determine the feasibility, reproducibility, and repeatability of elastography; and to describe elastographic characteristics of metacarpal tendons in sound horses. Nineteen legs for 17 clinically sound horses without evidence of musculoskeletal pathology were included. Elastographic images of the superficial and deep digital flexor tendons and the branches of the suspensory ligament (tendon of the interosseous muscle) were described quantitatively and qualitatively. There was no statistically significant difference between operators (P = 0.86) nor within operators (P = 0.93). For qualitative assessments, reproducibility (0.46) was moderate and repeatability (0.78) was good. Similar to human Achilles tendons, equine tendons were classified as predominantly hard using elastography. There was no statistically significant difference in stiffness of the flexor tendons (P = 0.96). No significant difference in stiffness was found with altered leg position during standing (P = 0.84) and while nonweight bearing (P = 0.61). The flexor tendons were softer when imaged in longitudinal versus transverse planes (P < 0.01) however, the suspensory branches were not (P = 0.67). Findings supported future clinical application of elastography as a noninvasive "stall-side" imaging modality for evaluation of the tendons and ligaments of the distal forelimb in horses.

  8. [Connective tissue reinforcing structures of the digital tendon sheaths of the human hand].

    PubMed

    Knott, C; Schmidt, H M

    1986-01-01

    At a greater number of humid preparated human hands, all the ligamentous supports of the digital tendon sheath were exposed and their dimensions were determined. The osteofibrous channels, which contain the long flexor tendons of the digits, were bounded on the one hand by transversely concave shaft areas of the phalanges and the palmar ligaments and on the other side by the fibrous parts of the tendon sheath. From the second to the 5th finger, it has a regular extension of length, which begins proximal at the heads of the metacarpal bones and runs distal to the base of the nail phalanx. In some cases, there is a continuous communication between the digital tendon sheath of the little finger and the carpal synovial sheath. The tendon sheath of the flexor pollicis longus muscle in comparison with it is always in an open communication with the radial synovial sac of the wrist. At the fibrous supports of the digital tendon sheath, one can find constant and inconstant ligamentous structures. Regular shaped ligaments consist of annular fibers (A1 to A5). The proximal complex of fiber supports is a formation of the A1 and A2 ligaments. The band A1 can be divided into 2 ligaments both of roughly equal length, which lay between the head of the metacarpal bone and the base of the proximal phalanx. The strongest fibrous support of the whole digital tendon sheath represents the band A2. It is attached to the midth of the proximal phalanx and increases in strength from proximal to distal. The middle length varies between 6.7 mm at the thumb and 18.7 mm at the middle finger. The distal margin is strengthened by fibrocartilage tissue to be in accordance with the important function as a pulley. The annular band A4 forms the distal supporting complex height above the shaft of the middle phalanx. At the 2nd to the 5th finger it is, with a middle length of 6 to 7 mm, very much shorter than A2 and restrains first of all the tendon of the flexor digitorum profundus muscle. In the area

  9. Development of a reinforced electrochemically aligned collagen bioscaffold for tendon tissue engineering applications

    NASA Astrophysics Data System (ADS)

    Uquillas Paredes, Jorge Alfredo

    Type-I collagen is a promising biomaterial that can be used to synthesize bioscaffolds as a strategy to regenerate and repair damaged tendons. The existing in vitro prepared collagen bioscaffolds are in the form of gels, foams, or extruded fibers. These bioscaffolds readily present sites for attachment of biological factors and cells; however, they have extremely poor biomechanical properties in comparison to the properties of native tendons. The biomechanical function of type-I collagen bioscaffolds needs to be elevated to the level of natural tissues for this biomaterial to replace mechanically challenged tendons in a functionally meaningful way. The overall goal of this dissertation is to develop a reinforced electrochemically aligned collagenous bioscaffold for applications in tendon tissue engineering. The bioscaffold is synthesized by a unique electrochemical process via isoelectric focusing (IEF) to attain a very high degree of molecular alignment and packing density. This dissertation presents progress made on four aims: A) development of simple and descriptive electrochemical theory via the mathematical model of IEF and the forces acting on collagen alignment under an electric field; B) optimization of the post-alignment PBS treatment step to achieve d- banding pattern in uncrosslinked electrochemically aligned collagen (ELAC) bioscaffolds; C) optimization of the best crosslinking protocol to produce the strongest possible ELAC biomaterial with excellent cellular compatibility; and D) in vivo evaluation of the biocompatibility and biodegradability properties of electronically aligned collagen bioscaffolds. The results of this dissertation provide strong evidence showing that reinforced ELAC bioscaffolds could be used clinically in the future to repair damaged tendons.

  10. Reduction in tendon elasticity from unloading is unrelated to its hypertrophy.

    PubMed

    Kinugasa, Ryuta; Hodgson, John A; Edgerton, V Reggie; Shin, David D; Sinha, Shantanu

    2010-09-01

    Tendinous tissues respond to chronic unloading with adaptive changes in mechanical, elastic, and morphological properties. However, little is known about the changes in the detailed structures of the entire tendinous tissue and whether the change in tendon stiffness is related to morphology. We investigated changes in dimensional (volume, cross-sectional area, segmented lengths) and elastic (Young's modulus) properties of the Achilles tendon and distal aponeurosis in response to chronic unilateral lower limb suspension (ULLS) using velocity encoded phase contrast (VE-PC) and three-dimensional morphometric magnetic resonance imaging (MRI). Five healthy subjects underwent ULLS for 4 wk. Axial morphometric MRI was acquired along the entire length from the calcaneous to the medial gastrocnemius insertion. An oblique sagittal VE-PC MRI was also acquired. The Young's modulus could be calculated from this cine dynamic sequence of velocity encoded images from the slope of the stress-strain curve during the submaximal isometric plantar flexion. After 4 wk of ULLS, we found significant (46.7%) decrease in maximum plantar flexion torque. The total volumes of entire tendinous tissue (determined as the sum of the Achilles tendon and distal aponeurosis) increased significantly by 6.4% (11.9 vs. 12.7 ml) after ULLS. In contrast, Young's modulus decreased significantly by 10.4% (211.7 vs. 189.6 MPa) for the Achilles tendon and 29.0% for the distal aponeurosis (158.8 vs. 113.0 MPa) following ULLS. There was no significant correlation between relative change in volume and Young's modulus with 4 wk of ULLS. It is suggested that, although tendon hypertrophy can be expected to adversely affect tendon stiffness, the absence of any significant correlation between the magnitude of tendon hypertrophy and reduced Young's modulus indicates that dimensional factors were not critical to the elastic properties.

  11. Tendon's ultrastructure.

    PubMed

    Tresoldi, Ilaria; Oliva, Francesco; Benvenuto, Monica; Fantini, Massimo; Masuelli, Laura; Bei, Roberto; Modesti, Andrea

    2013-01-01

    The structure of a tendon is an important example of complexity of ECM three-dimensional organization. The extracellular matrix (ECM) is a macromolecular network with both structural and regulatory functions. ECM components belong to four major types of macromolecules: the collagens, elastin, proteoglycans, and noncollagenous glycoproteins. Tendons are made by a fibrous, compact connective tissue that connect muscle to bone designed to transmit forces and withstand tension during muscle contraction. Here we show the ultrastructural features of tendon's components.

  12. Repetitive differential finger motion increases shear strain between the flexor tendon and subsynovial connective tissue.

    PubMed

    Tat, Jimmy; Kociolek, Aaron M; Keir, Peter J

    2013-10-01

    Non-inflammatory fibrosis and thickening of the subsynovial connective tissue (SSCT) are characteristic in carpal tunnel syndrome (CTS) patients. These pathological changes have been linked to repetitive hand tasks that create shear forces between the flexor tendons and SSCT. We measured the relative motion of the flexor digitorum superficialis tendon and SSCT during two repetitive finger tasks using color Doppler ultrasound. Twelve participants performed flexion-extension cycles for 30 min with the long finger alone (differential movement) and with all four fingers together (concurrent movement). Shear strain index (SSI, a relative measure of excursion in flexion and extension) and maximum velocity ratio (MVR, the ratio of SSCT versus tendon during flexion and extension) were used to represent shear. A linear effect of exertion time was significant and corresponded with larger tendon shear in differential motion. The flexion SSI increased 20.4% from the first to the 30th minute, while MVR decreased 8.9% in flexion and 8.7% in extension. No significant changes were found during concurrent motion. These results suggest that exposure to repetitive differential finger tasks may increase the risk of shear injury in the carpal tunnel.

  13. Functional Characterization of Detergent-Decellularized Equine Tendon Extracellular Matrix for Tissue Engineering Applications

    PubMed Central

    Youngstrom, Daniel W.; Barrett, Jennifer G.; Jose, Rod R.; Kaplan, David L.

    2013-01-01

    Natural extracellular matrix provides a number of distinct advantages for engineering replacement orthopedic tissue due to its intrinsic functional properties. The goal of this study was to optimize a biologically derived scaffold for tendon tissue engineering using equine flexor digitorum superficialis tendons. We investigated changes in scaffold composition and ultrastructure in response to several mechanical, detergent and enzymatic decellularization protocols using microscopic techniques and a panel of biochemical assays to evaluate total protein, collagen, glycosaminoglycan, and deoxyribonucleic acid content. Biocompatibility was also assessed with static mesenchymal stem cell (MSC) culture. Implementation of a combination of freeze/thaw cycles, incubation in 2% sodium dodecyl sulfate (SDS), trypsinization, treatment with DNase-I, and ethanol sterilization produced a non-cytotoxic biomaterial free of appreciable residual cellular debris with no significant modification of biomechanical properties. These decellularized tendon scaffolds (DTS) are suitable for complex tissue engineering applications, as they provide a clean slate for cell culture while maintaining native three-dimensional architecture. PMID:23724028

  14. Potency of double-layered poly L-lactic acid scaffold in tissue engineering of tendon tissue.

    PubMed

    Inui, Atsuyuki; Kokubu, Takeshi; Makino, Takeshi; Nagura, Issei; Toyokawa, Narikazu; Sakata, Ryosuke; Kotera, Masaru; Nishino, Takashi; Fujioka, Hiroyuki; Kurosaka, Masahiro

    2010-12-01

    A successful scaffold for use in tendon tissue engineering requires a high affinity for living organisms and the ability to maintain its mechanical strength until maturation of the regenerated tissue. We compared two types of poly(L-lactic acid) (PLLA) scaffolds for use in tendon regeneration, a plain-woven PLLA fabric (fabric P) with a smooth surface only and a double layered PLLA fabric (fabric D) with a smooth surface on one side and a rough (pile-finished) surface on the other side. These two types of fabric were implanted into the back muscles of rabbits and evaluated at three and six weeks after implantation. Histological examination showed collagen tissues were highly regenerated on the rough surface of fabric D. On the other hand, liner cell attachment was seen in the smooth surface of fabric P and fabric D. The total DNA amount was significantly higher in fabric D. Additionally, mechanical examination showed fabric P had lost its mechanical strength by six weeks after implantation, while the strength of fabric D was maintained. Fabric D had more cell migration on one side and less cell adhesion on the other side and maintained its initial strength. Thus, a novel form of double-layered PLLA fabric has the potential to be used as a scaffold in tendon regeneration.

  15. Effects of acute static, ballistic, and PNF stretching exercise on the muscle and tendon tissue properties.

    PubMed

    Konrad, A; Stafilidis, S; Tilp, M

    2016-07-01

    The purpose of this study was to investigate the influence of a single static, ballistic, or proprioceptive neuromuscular facilitation (PNF) stretching exercise on the various muscle-tendon parameters of the lower leg and to detect possible differences in the effects between the methods. Volunteers (n = 122) were randomly divided into static, ballistic, and PNF stretching groups and a control group. Before and after the 4 × 30 s stretching intervention, we determined the maximum dorsiflexion range of motion (RoM) with the corresponding fascicle length and pennation angle of the gastrocnemius medialis. Passive resistive torque (PRT) and maximum voluntary contraction (MVC) were measured with a dynamometer. Observation of muscle-tendon junction (MTJ) displacement with ultrasound allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate stiffness. Although RoM increased (static: +4.3%, ballistic: +4.5%, PNF: +3.5%), PRT (static: -11.4%, ballistic: -11.5%, PNF: -13,7%), muscle stiffness (static: -13.1%, ballistic: -20.3%, PNF: -20.2%), and muscle-tendon stiffness (static: -11.3%, ballistic: -10.5%, PNF: -13.7%) decreased significantly in all the stretching groups. Only in the PNF stretching group, the pennation angle in the stretched position (-4.2%) and plantar flexor MVC (-4.6%) decreased significantly. Multivariate analysis showed no clinically relevant difference between the stretching groups. The increase in RoM and the decrease in PRT and muscle-tendon stiffness could be explained by more compliant muscle tissue following a single static, ballistic, or PNF stretching exercise.

  16. Measurement of rectus femoris muscle velocities during patellar tendon jerk using vector tissue doppler imaging.

    PubMed

    Sikdar, Siddhartha; Lebiedowska, Maria; Eranki, Avinash; Garmirian, Lindsay; Damiano, Diane

    2009-01-01

    We have developed a vector tissue Doppler imaging (TDI) system based on a clinical scanner that can be used to measure muscle velocities independent of the direction of motion. This method overcomes the limitations of conventional Doppler ultrasound, which can only measure velocity components along the ultrasound beam. In this study, we utilized this method to investigate the rectus femoris muscle velocities during a patellar tendon jerk test. Our goal was to investigate whether the muscle elongation velocities during a brisk tendon tap fall within the normal range of velocities that are expected due to rapid stretch of limb segments. In a preliminary study, we recruited six healthy volunteers (three men and three women) following informed consent. The stretch reflex response to tendon tap was evaluated by measuring: (1) the tapping force using an accelerometer instrumented to the neurological hammer (2) the angular velocities of the knee extension and flexion using a electrogoniometer (3) reflex activation using electromyography (EMG) and (4) muscle elongation, extension and flexion velocities using vector TDI. The passive joint angular velocity was linearly related to the passive muscle elongation velocity (R(2)=0.88). The maximum estimated joint angular velocity corresponding to muscle elongation due to tendon tap was less than 8.25 radians/s. This preliminary study demonstrates the feasibility of vector TDI for measuring longitudinal muscle velocities and indicates that the muscle elongation velocities during a clinical tendon tap test are within the normal range of values for rapid limb stretch encountered in daily life. With further refinement, vector TDI could become a powerful method for quantitative evaluation of muscle motion in musculoskeletal disorders.

  17. IMPROVEMENT OF TENDON REPAIR USING MUSCLE GRAFTS TRANSDUCED WITH TGF-β1 cDNA

    PubMed Central

    Majewski, Martin; Porter, Ryan M.; Betz, Oliver B.; Betz, Volker M.; Clahsen, Harald; Flückiger, Rudolf; Evans, Christopher H.

    2015-01-01

    Tendon rupture is a common injury. Inadequate endogenous repair often leaves patients symptomatic, with tendons susceptible to re-rupture. Administration of certain growth factors improves tendon healing in animal models, but their delivery remains a challenge. Here we evaluated the delivery of TGF-β1 to tendon defects by the implantation of genetically modified muscle grafts. Rat muscle biopsies were transduced with recombinant adenovirus encoding TGF-β1 and grafted onto surgically transected Achilles tendons in recipient animals. Tissue regenerates were compared to those of controls by biomechanical testing as well as histochemical and immunohistochemical analyses. Healing was greatly accelerated when genetically modified grafts were implanted into tendon defects, with the resulting repair tissue gaining nearly normal histological appearance as early as 2 weeks postoperatively. This was associated with decreased deposition of type III collagen in favour of large fibre bundles indicative of type I collagen. These differences in tendon composition coincided with accelerated restoration of mechanical strength. Tendon thickness increased in gene-treated animals at weeks 1 and 2, but by week 8 became significantly lower than that of controls suggesting accelerated remodelling. Thus localised TGF-β1 delivery via adenovirus-modified muscle grafts improved tendon healing in this rat model and holds promise for clinical application. PMID:22354460

  18. The role of collagen arrangement change during tendon healing demonstrated by scanning electron microscopy.

    PubMed

    Sasaki, Kaoru; Yamamoto, Naoto; Kiyosawa, Tomoharu; Sekido, Mitsuru

    2012-01-01

    The dry weight of tendon tissue is accounted for mainly by collagen fibers. Accordingly, the tendon-healing process primarily involves repair of collagen fibers. During the remodeling phase of tendon healing, newly proliferating collagen fibers are transformed into a mature repaired tendon. Despite the importance of this phenomenon, the details of fibrous rebuilding have not been reported previously. The aim of this study was to visualize the ultrastructural changes and to obtain a clear understanding of the reorganization of the collagen fibers in the tendon repair site, using rat Achilles tendons. We used scanning electron microscopy (SEM) with cell maceration as the main method of analysis. Pretreatment with cell maceration removed the cellular components successfully. This allowed precise visualization of each collagen fiber and the three-dimensional network of the fibers. This study was the first to apply the cell-maceration/SEM method to observe tendon tissue. Seven days after surgery, new collagen fibers grew extensively in the repair site in a random arrangement. Fourteen days after surgery, the collagen fibers began to form an axial arrangement. Near the tendon stump, this change progressed from the outer layer to the core region. On the other hand, in the middle of the repair site, it progressed from the core to the outer layer. Change in the axial arrangement of collagen fibers contributes to the connection between the repair site and the tendon stump and to the separation of the repair site from the paratenon.

  19. Regeneration and repair of tendon and ligament tissue using collagen fibre biomaterials.

    PubMed

    Kew, S J; Gwynne, J H; Enea, D; Abu-Rub, M; Pandit, A; Zeugolis, D; Brooks, R A; Rushton, N; Best, S M; Cameron, R E

    2011-09-01

    Collagen fibres are ubiquitous macromolecular assemblies in nature, providing the structures that support tensile mechanical loads within the human body. Aligned type I collagen fibres are the primary structural motif for tendon and ligament, and therefore biomaterials based on these structures are considered promising candidates for mediating regeneration of these tissues. However, despite considerable investigation, there remains no collagen-fibre-based biomaterial that has undergone clinical evaluation for this application. Recent research in this area has significantly enhanced our understanding of these complex and challenging biomaterials, and is reinvigorating interest in the development of such structures to recapitulate mechanical function. In this review we describe the progress to date towards a ligament or tendon regeneration template based on collagen fibre scaffolds. We highlight reports of particular relevance to the development of the underlying biomaterials science in this area. In addition, the potential for tailoring and manipulating the interactions between collagen fibres and biological systems, as hybrid biomaterial-biological ensembles, is discussed in the context of developing novel tissue engineering strategies for tendon and ligament.

  20. Is Echogenicity a Viable Metric for Evaluating Tendon Properties In Vivo?

    PubMed Central

    Suydam, Stephen M.; Buchanan, Thomas S.

    2014-01-01

    Material properties of tissue in vivo present an opportunity for clinical analysis of healing progression and pathologies as well as provide an excellent research tool yielding quantified data for longitudinal and cross population studies. Echogenicity is a material’s ability to reflect sound and, using ultrasound, it has been shown to increase with tendon tension in vitro, though this non-invasive measurement technique for determining mechanical properties has not been tested in vivo. The aim of this study was to establish if echogenicity, seen by the increase in image brightness, could be correlated to stress within a tissue. 18 Achilles tendons were imaged in the sagittal and transverse planes while producing a series of isometric contractions starting from rest and producing the torque equivalent of 0.5, 1.0, 1.5, and 2.0x body weights. Manual tracing identified the tendon in each of the images. The cross-sectional area determined from the transverse plane images in conjunction with the tendon force yielded the tendon stress. The echogenicity of the tendon was determined from the mean brightness change from rest to each of the contraction cases, measured from the sagittal plane images. A weak correlation existed between the echogenicity and stress (R = 0.25) but it was found that there was no significant change in axial area during contraction (p = 0.683) establishing then tendon as incompressible. Echogenicity proved to be non-functional for measuring the mechanical properties of the Achilles tendon due to the additional factors included with in vivo testing e.g. tendon twist and multi-axial loading. PMID:24726653

  1. Tendon repair

    MedlinePlus

    ... is pain-free) Regional anesthesia (the local and surrounding areas are pain-free) General anesthesia (the patient ... used. If needed, tendons are reattached to the surrounding tissue. The surgeon examines the area to see ...

  2. 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.

  3. Muscle and tendon connective tissue adaptation to unloading, exercise and NSAID.

    PubMed

    Dideriksen, Kasper

    2014-04-01

    The extracellular matrix network of skeletal muscle and tendon connective tissue is primarily composed of collagen and connects the muscle contractile protein to the bones in the human body. The mechanical properties of the connective tissue are important for the effectiveness of which the muscle force is transformed into movement. Periods of unloading and exercise affect the synthesis rate of connective tissue collagen protein, whereas only sparse information exits regarding collagen protein degradation. It is likely, though, that changes in both collagen protein synthesis and degradation are required for remodeling of the connective tissue internal structure that ultimately results in altered mechanical properties of the connective tissue. Both unloading and exercise lead to increased production of growth factors and inflammatory mediators that are involved in connective tissue remodeling. Despite the fact that non-steroidal anti-inflammatory drugs seem to inhibit the healing process of connective tissue and the stimulating effect of exercise on connective tissue protein synthesis, these drugs are often consumed in relation to connective tissue injury and soreness. However, the potential effect of non-steroidal anti-inflammatory drugs on connective tissue needs further investigation.

  4. Mapping lubricin in canine musculoskeletal tissues.

    PubMed

    Sun, Yulong; Berger, Evelyn J; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C; Jay, Gregory

    2006-01-01

    Lubricin, also known as superficial zone protein or PRG4, has many distinct biological functions, including lubrication, antiadhesion, and as a regulator of cell growth. This study investigated lubricin in canine musculoskeletal tissues using RT-PCR and immunohistochemistry. One or more variants were noted in canine flexor digitorum profundus (FDP) tendon, Achilles tendon, patellar tendon, A2 pulley, anterior cruciate ligament (ACL), knee lateral collateral ligament (LCL), articular cartilage, meniscus, muscle, and skin. We found 6 N-terminal lubricin splicing variants. The variants with larger sizes were identified in FDP tendon, ACL, LCL, A2 pulley, and cartilage. Lubricin was distributed both on the tissue surfaces and at the interface of fiber bundles within tissues, but this distribution varied by tissue type. We conclude that lubricin is present in many tissues; variations in splicing and physical distribution suggest that the variants of lubricin may play different roles in different locations.

  5. The pathogenesis of Achilles tendinopathy: a systematic review.

    PubMed

    Magnan, Bruno; Bondi, Manuel; Pierantoni, Silvia; Samaila, Elena

    2014-09-01

    Achilles tendinopathy is a degenerative, not an inflammatory, condition. It is prevalent in athletes involved in running sports. A systematic literature review on Achilles tendon tendinopathy has been performed according to the intrinsic (age, sex, body weight, tendon temperature, systemic diseases, muscle strength, flexibility, previous injuries and anatomical variants, genetic predisposition and blood supply) and extrinsic risk factors (drugs and overuse), which can cause tendon suffering and degeneration. Different theories have been found: Neurogenic, Angiogenic, Impingement and "Iceberg" Hypotheses. Multiple databases were utilized for articles published between 1964 and 2013. The different hypothesis were analyzed, differently considering those concerning the pathogenesis of tendinopathy and those concerning the etiology of complaints in patients. This review of the literature demonstrates the heterogeneity of Achilles tendinopathy pathogenesis. Various risk factors have been identified and have shown an interaction between them such as genes, age, circulating and local cytokine production, sex, biomechanics and body composition.

  6. The effect of mechanical stimulation on the maturation of TDSCs-poly(L-lactide-co-e-caprolactone)/collagen scaffold constructs for tendon tissue engineering.

    PubMed

    Xu, Yuan; Dong, Shiwu; Zhou, Qiang; Mo, Xiumei; Song, Lei; Hou, Tianyong; Wu, Jinglei; Li, Songtao; Li, Yudong; Li, Pei; Gan, Yibo; Xu, Jianzhong

    2014-03-01

    Mechanical stimulation plays an important role in the development and remodeling of tendons. Tendon-derived stem cells (TDSCs) are an attractive cell source for tendon injury and tendon tissue engineering. However, these cells have not yet been fully explored for tendon tissue engineering application, and there is also lack of understanding to the effect of mechanical stimulation on the maturation of TDSCs-scaffold construct for tendon tissue engineering. In this study, we assessed the efficacy of TDSCs in a poly(L-lactide-co-ε-caprolactone)/collagen (P(LLA-CL)/Col) scaffold under mechanical stimulation for tendon tissue engineering both in vitro and in vivo, and evaluated the utility of the transplanted TDSCs-scaffold construct to promote rabbit patellar tendon defect regeneration. TDSCs displayed good proliferation and positive expressed tendon-related extracellular matrix (ECM) genes and proteins under mechanical stimulation in vitro. After implanting into the nude mice, the fluorescence imaging indicated that TDSCs had long-term survival, and the macroscopic evaluation, histology and immunohistochemistry examinations showed high-quality neo-tendon formation under mechanical stimulation in vivo. Furthermore, the histology, immunohistochemistry, collagen content assay and biomechanical testing data indicated that dynamically cultured TDSCs-scaffold construct could significantly contributed to tendon regeneration in a rabbit patellar tendon window defect model. TDSCs have significant potential to be used as seeded cells in the development of tissue-engineered tendons, which can be successfully fabricated through seeding of TDSCs in a P(LLA-CL)/Col scaffold followed by mechanical stimulation.

  7. IL-1β irreversibly inhibits tenogenic differentiation and alters metabolism in injured tendon-derived progenitor cells in vitro.

    PubMed

    Zhang, Kairui; Asai, Shuji; Yu, Bin; Enomoto-Iwamoto, Motomi

    2015-08-07

    Tendon injuries are common, and the damaged tendon often turns into scar tissue and never completely regains the original biomechanical properties. Previous studies have reported that the mRNA levels of inflammatory cytokines such as IL-1β are remarkably up-regulated in injured tendons. To examine how IL-1β impacts tendon repair process, we isolated the injured tendon-derived progenitor cells (inTPCs) from mouse injured Achilles tendons and studied the effects of IL-1β on the inTPCs in vitro. IL-1β treatment strongly reduced expression of tendon cell markers such as scleraxis and tenomodulin, and also down-regulated gene expression of collagen 1, collagen 3, biglycan and fibromodulin in inTPCs. Interestingly, IL-1β stimulated lactate production with increases in hexokinase II and lactate dehydrogenase expression and a decrease in pyruvate dehydrogenase. Inhibition of lactate production restored IL-1β-induced down-regulation of collagen1 and scleraxis expression. Furthermore, IL-1β significantly inhibited adipogenic, chondrogenic and osteogenic differentiation of inTPCs. Interestingly, inhibition of tenogenic and adipogenic differentiation was not recovered after removal of IL-1β while chondrogenic and osteogenic differentiation abilities were not affected. These findings indicate that IL-1β strongly and irreversibly impairs tenogenic potential and alters glucose metabolism in tendon progenitors appearing in injured tendons. Inhibition of IL-1β may be beneficial for maintaining function of tendon progenitor cells during the tendon repair process.

  8. To cipro or not to cipro: bilateral achilles ruptures with the use of quinolones.

    PubMed

    Seidel, Jay; Clarke, Terry; Mathew, Bindu

    2015-03-01

    Ciprofloxacin and other fluoroquinolones are commonly used broad-spectrum antimicrobial agents for treating bacterial infections. This class of antibiotic drugs has uncommon adverse effects that include tendonitis, tendon ruptures, and other tendon abnormalities. We describe a patient with spontaneous bilateral complete Achilles tendon rupture after ciprofloxacin treatment. Surgical repair was performed successfully, and the patient completed physical rehabilitation without incident. Care should be exercised when selecting pharmaceutical agents to maintain a positive benefit-to-risk balance.

  9. Nonsurgical Management of Midsubstance Achilles Tendinopathy.

    PubMed

    McClinton, Shane; Luedke, Lace; Clewley, Derek

    2017-04-01

    Midsubstance Achilles tendinopathy is one of the most common lower leg conditions. Most patients can recover with nonsurgical treatment that focuses on tendon loading exercises and, when necessary, symptom modulating treatments such as topical, oral, or injected medication, ice, shoe inserts, manual therapy, stretching, taping, or low-level laser. If unresponsive to initial management, a small percentage of patients may consider shockwave or sclerosing treatment and possibly surgery.

  10. Uniformly-dispersed nanohydroxapatite-reinforced poly(ε-caprolactone) composite films for tendon tissue engineering application.

    PubMed

    Tong, Shi Yun; Wang, Zuyong; Lim, Poon Nian; Wang, Wilson; Thian, Eng San

    2017-01-01

    Regeneration of injuries at tendon-to-bone interface (TBI) remains a challenging issue due to the complex tissue composition involving both soft tendon tissues and relatively hard bone tissues. Tissue engineering using polymeric/ceramic composites has been of great interest to generate scaffolds for tissue's healing at TBI. Herein, we presented a novel method to blend polymers and bioceramics for tendon tissue engineering application. A homogeneous composite comprising of nanohydroxyapatite (nHA) particles in poly(ε-caprolactone) (PCL) matrix was obtained using a combination of solvent and mechanical blending process. X-ray diffraction analysis showed that the as-fabricated PCL/nHA composite film retained phase-pure apatite and semi-crystalline properties of PCL. Infrared spectroscopy spectra confirmed that the PCL/nHA composite film exhibited the characteristics functional groups of PCL and nHA, without alteration to the chemical properties of the composite. The incorporation of nHA resulted in PCL/nHA composite film with improved mechanical properties such as Young's Modulus and ultimate tensile stress, which were comparable to that of the native human rotator tendon. Seeding with human tenocytes, cells attached on the PCL/nHA composite film, and after 14days of culturing, these cells could acquire elongated morphology without induced cytotoxicity. PCL/nHA composite film could also result in increased cell metabolism with prolonged culturing, which was comparable to that of the PCL group and higher than that of the nHA group. All these results demonstrated that the developed technique of combining solvent and mechanical blending could be applied to fabricate composite films with potential for tendon tissue engineering applications.

  11. Low frequency pulsed electromagnetic field affects proliferation, tissue-specific gene expression, and cytokines release of human tendon cells.

    PubMed

    de Girolamo, L; Stanco, D; Galliera, E; Viganò, M; Colombini, A; Setti, S; Vianello, E; Corsi Romanelli, M M; Sansone, V

    2013-07-01

    Low frequency pulsed electromagnetic field (PEMF) has proven to be effective in the modulation of bone and cartilage tissue functional responsiveness, but its effect on tendon tissue and tendon cells (TCs) is still underinvestigated. PEMF treatment (1.5 mT, 75 Hz) was assessed on primary TCs, harvested from semitendinosus and gracilis tendons of eight patients, under different experimental conditions (4, 8, 12 h). Quantitative PCR analyses were conducted to identify the possible effect of PEMF on tendon-specific gene transcription (scleraxis, SCX and type I collagen, COL1A1); the release of pro- and anti-inflammatory cytokines and of vascular endothelial growth factor (VEGF) was also assessed. Our findings show that PEMF exposure is not cytotoxic and is able to stimulate TCs' proliferation. The increase of SCX and COL1A1 in PEMF-treated cells was positively correlated to the treatment length. The release of anti-inflammatory cytokines in TCs treated with PEMF for 8 and 12 h was significantly higher in comparison with untreated cells, while the production of pro-inflammatory cytokines was not affected. A dramatically higher increase of VEGF-A mRNA transcription and of its related protein was observed after PEMF exposure. Our data demonstrated that PEMF positively influence, in a dose-dependent manner, the proliferation, tendon-specific marker expression, and release of anti-inflammatory cytokines and angiogenic factor in a healthy human TCs culture model.

  12. Evidence that interfibrillar load transfer in tendon is supported by small diameter fibrils and not extrafibrillar tissue components.

    PubMed

    Szczesny, Spencer E; Fetchko, Kristen L; Dodge, George R; Elliott, Dawn M

    2017-01-10

    Collagen fibrils in tendon are believed to be discontinuous and transfer tensile loads through shear forces generated during interfibrillar sliding. However, the structures that transmit these interfibrillar forces are unknown. Various extrafibrillar tissue components (e.g., glycosaminoglycans, collagens XII and XIV) have been suggested to transmit interfibrillar loads by bridging collagen fibrils. Alternatively, collagen fibrils may interact directly through physical fusions and interfibrillar branching. The objective of this study was to test whether extrafibrillar proteins are necessary to transmit load between collagen fibrils or if interfibrillar load transfer is accomplished directly by the fibrils themselves. Trypsin digestions were used to remove a broad spectrum of extrafibrillar proteins and measure their contribution to the multiscale mechanics of rat tail tendon fascicles. Additionally, images obtained from serial block-face scanning electron microscopy were used to determine the three-dimensional fibrillar organization in tendon fascicles and identify any potential interfibrillar interactions. While trypsin successfully removed several extrafibrillar tissue components, there was no change in the macroscale fascicle mechanics or fibril:tissue strain ratio. Furthermore, the imaging data suggested that a network of smaller diameter fibrils (<150 nm) wind around and fuse with their neighboring larger diameter fibrils. These findings demonstrate that interfibrillar load transfer is not supported by extrafibrillar tissue components and support the hypothesis that collagen fibrils are capable of transmitting loads themselves. Conclusively determining how fibrils bear load within tendon is critical for identifying the mechanisms that impair tissue function with degeneration and for restoring tissue properties via cell-mediated regeneration or engineered tissue replacements. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop

  13. Enforced bipedal downhill running induces Achilles tendinosis in rats.

    PubMed

    Ng, Gabriel Yin-Fat; Chung, Polly Yee-Man; Wang, Jenny Shijie; Cheung, Roy Tsz-Hei

    2011-01-01

    Enforced downhill running has been reported to induce tendinosis in the rat supraspinatus tendon but similar exercise failed to induce Achilles tendinosis in this animal. Due to the presence of acromial arch in the shoulder, accessing the supraspinatus tendon with physical modalities is difficult; thus this model may not be suitable for studying the treatment for tendinosis. To develop a rat model for Achilles tendinosis, we tested 14 mature Sprague-Dawley rats by dividing them into 2 groups of 7 each. The experimental group was subjected to a daily enforced downhill bipedal running program by suspending their upper bodies so that they ran with their hind limbs on a treadmill for 1 hr/day for 8 weeks. The downward inclination was 20 degrees and the speed was 17 m/min. The animals in the control group did not undergo any exercise. After 8 weeks, the Achilles tendons were harvested and subjected to histological and biomechanical analysis. Histological examination revealed tenocyte proliferation, change in tenocytes appearance, and collagen bundle disintegration in the running group. The biomechanical testing revealed significant decrease in stiffness (p = 0.002) and ultimate tensile strength (p = 0.016) in the running group than in the control group. Both the histological and biomechanical findings are suggestive of changes in the tendon of the running group that resembled the pathological changes of tendinosis in human. This new model of Achilles tendinosis in rat will be useful for studying the etiology and subsequent management strategies of this condition.

  14. IN VIVO MEASURES OF SHEAR WAVE SPEED AS A PREDICTOR OF TENDON ELASTICITY AND STRENGTH

    PubMed Central

    Martin, Jack A.; Biedrzycki, Adam H.; Lee, Kenneth S.; DeWall, Ryan J.; Brounts, Sabrina H.; Murphy, William L.; Markel, Mark D.; Thelen, Darryl G.

    2015-01-01

    The purpose of this study was to assess the potential for ultrasound shear wave elastography (SWE) to assess tissue elasticity and ultimate stress in both intact and healing tendons. The lateral gastrocnemius (Achilles) tendons of 41 New Zealand white rabbits were surgically severed and repaired with growth factor coated sutures. SWE imaging was used to measure shear wave speed (SWS) in both the medial and lateral tendons pre-surgery, and at 2 and 4 weeks post-surgery. Rabbits were euthanized at 4 weeks, and both medial and lateral tendons underwent mechanical testing to failure. SWS significantly (p<0.001) decreased an average of 17% between the intact and post-surgical state across all tendons. SWS was significantly (p<0.001) correlated with both the tendon elastic modulus (r = 0.52) and ultimate stress (r = 0.58). Thus, ultrasound SWE is a potentially promising noninvasive technology for quantitatively assessing the mechanical integrity of pre-operative and post-operative tendons. PMID:26215492

  15. In Vivo Measures of Shear Wave Speed as a Predictor of Tendon Elasticity and Strength.

    PubMed

    Martin, Jack A; Biedrzycki, Adam H; Lee, Kenneth S; DeWall, Ryan J; Brounts, Sabrina H; Murphy, William L; Markel, Mark D; Thelen, Darryl G

    2015-10-01

    The purpose of this study was to assess the potential for ultrasound shear wave elastography (SWE) to measure tissue elasticity and ultimate stress in both intact and healing tendons. The lateral gastrocnemius (Achilles) tendons of 41 New Zealand white rabbits were surgically severed and repaired with growth factor coated sutures. SWE imaging was used to measure shear wave speed (SWS) in both the medial and lateral tendons pre-surgery, and at 2 and 4 wk post-surgery. Rabbits were euthanized at 4 wk, and both medial and lateral tendons underwent mechanical testing to failure. SWS significantly (p < 0.001) decreased an average of 17% between the intact and post-surgical state across all tendons. SWS was significantly (p < 0.001) correlated with both the tendon elastic modulus (r = 0.52) and ultimate stress (r = 0.58). Thus, ultrasound SWE is a potentially promising non-invasive technology for quantitatively assessing the mechanical integrity of pre-operative and post-operative tendons.

  16. Musculoskeletal diseases—tendon

    PubMed Central

    Sakabe, Tomoya; Sakai, Takao

    2011-01-01

    Introduction Tendons establish specific connections between muscles and the skeleton by transferring contraction forces from skeletal muscle to bone thereby allowing body movement. Tendon physiology and pathology are heavily dependent on mechanical stimuli. Tendon injuries clinically represent a serious and still unresolved problem since damaged tendon tissues heal very slowly and no surgical treatment can restore a damaged tendon to its normal structural integrity and mechanical strength. Understanding how mechanical stimuli regulate tendon tissue homeostasis and regeneration will improve the treatment of adult tendon injuries that still pose a great challenge in today's medicine. Source of data This review summarizes the current status of tendon treatment and discusses new directions from the point of view of cell-based therapy and regenerative medicine approach. We searched the available literature using PubMed for relevant original articles and reviews. Growing points Identification of tendon cell markers has enabled us to study precisely tendon healing and homeostasis. Clinically, tissue engineering for tendon injuries is an emerging technology comprising elements from the fields of cellular source, scaffold materials, growth factors/cytokines and gene delivering systems. Areas timely for developing research The clinical settings to establish appropriate microenvironment for injured tendons with the combination of these novel cellular- and molecular-based scaffolds will be critical for the treatment. PMID:21729872

  17. 3-D ultrastructure and collagen composition of healthy and overloaded human tendon: evidence of tenocyte and matrix buckling

    PubMed Central

    Pingel, Jessica; Lu, Yinhui; Starborg, Tobias; Fredberg, Ulrich; Langberg, Henning; Nedergaard, Anders; Weis, MaryAnn; Eyre, David; Kjaer, Michael; Kadler, Karl E

    2014-01-01

    Achilles tendinopathies display focal tissue thickening with pain and ultrasonography changes. Whilst complete rupture might be expected to induce changes in tissue organization and protein composition, little is known about the consequences of non-rupture-associated tendinopathies, especially with regards to changes in the content of collagen type I and III (the major collagens in tendon), and changes in tendon fibroblast (tenocyte) shape and organization of the extracellular matrix (ECM). To gain new insights, we took biopsies from the tendinopathic region and flanking healthy region of Achilles tendons of six individuals with clinically diagnosed tendinopathy who had no evidence of cholesterol, uric acid and amyloid accumulation. Biochemical analyses of collagen III/I ratio were performed on all six individuals, and electron microscope analysis using transmission electron microscopy and serial block face-scanning electron microscopy were made on two individuals. In the tendinopathic regions, compared with the flanking healthy tissue, we observed: (i) an increase in the ratio of collagen III : I proteins; (ii) buckling of the collagen fascicles in the ECM; (iii) buckling of tenocytes and their nuclei; and (iv) an increase in the ratio of small-diameter : large-diameter collagen fibrils. In summary, load-induced non-rupture tendinopathy in humans is associated with localized biochemical changes, a shift from large-to small-diameter fibrils, buckling of the tendon ECM, and buckling of the cells and their nuclei. PMID:24571576

  18. Clinical commentary of the evolution of the treatment for chronic painful mid-portion Achilles tendinopathy

    PubMed Central

    Alfredson, Håkan

    2015-01-01

    The chronic painful Achilles tendon mid-portion was for many years, and still is in many countries, treated with intratendinous revision surgery. However, by coincidence, painful eccentric calf muscle training was tried, and it showed very good clinical results. This finding was unexpected and led to research into the pain mechanisms involved in this condition. Today we know that there are very few nerves inside, but multiple nerves outside, the ventral side of the chronic painful Achilles tendon mid-portion. These research findings have resulted in new treatment methods targeting the regions with nerves outside the tendon, methods that allow for a rapid rehabilitation and fast return to sports. PMID:26537813

  19. Nonuniform strain of human soleus aponeurosis-tendon complex during submaximal voluntary contractions in vivo.

    PubMed

    Finni, Taija; Hodgson, John A; Lai, Alex M; Edgerton, V Reggie; Sinha, Shantanu

    2003-08-01

    The distribution of strain along the soleus aponeurosis tendon was examined during voluntary contractions in vivo. Eight subjects performed cyclic isometric contractions (20 and 40% of maximal voluntary contraction). Displacement and strain in the apparent Achilles tendon and in the aponeurosis were calculated from cine phase-contrast magnetic resonance images acquired with a field of view of 32 cm. The apparent Achilles tendon lengthened 2.8 and 4.7% in 20 and 40% maximal voluntary contraction, respectively. The midregion of the aponeurosis, below the gastrocnemius insertion, lengthened 1.2 and 2.2%, but the distal aponeurosis shortened 2.1 and 2.5%, respectively. There was considerable variation in the three-dimensional anatomy of the aponeurosis and muscle-tendon junction. We suggest that the nonuniformity in aponeurosis strain within an individual was due to the presence of active and passive motor units along the length of the muscle, causing variable force along the measurement site. Force transmission along intrasoleus connective tissue may also be a significant source of nonuniform strain in the aponeurosis.

  20. Are Sport-Specific Profiles of Tendon Stiffness and Cross-Sectional Area Determined by Structural or Functional Integrity?

    PubMed Central

    Rieder, Florian; Kösters, Alexander; Müller, Erich; Seynnes, Olivier R.

    2016-01-01

    The present study aimed to determine whether distinct sets of tendon properties are seen in athletes engaged in sports with contrasting requirements for tendon function and structural integrity. Patellar and Achilles tendon morphology and force-deformation relation were measured by combining ultrasonography, electromyography and dynamometry in elite ski jumpers, distance runners, water polo players and sedentary individuals. Tendon cross-sectional area normalized to body mass2/3 was smaller in water polo players than in other athletes (patellar and Achilles tendon; -28 to -24%) or controls (patellar tendon only; -9%). In contrast, the normalized cross-sectional area was larger in runners (patellar tendon only; +26%) and ski jumpers (patellar and Achilles tendon; +21% and +13%, respectively) than in controls. Tendon stiffness normalized to body mass2/3 only differed in ski jumpers, compared to controls (patellar and Achilles tendon; +11% and +27%, respectively) and to water polo players (Achilles tendon only; +23%). Tendon size appears as an adjusting variable to changes in loading volume and/or intensity, possibly to preserve ultimate strength or fatigue resistance. However, uncoupled morphological and mechanical properties indicate that functional requirements may also influence tendon adaptations. PMID:27362657

  1. 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

  2. Mechanical Actuation Systems for the Phenotype Commitment of Stem Cell-Based Tendon and Ligament Tissue Substitutes.

    PubMed

    Govoni, Marco; Muscari, Claudio; Lovecchio, Joseph; Guarnieri, Carlo; Giordano, Emanuele

    2016-04-01

    High tensile forces transmitted by tendons and ligaments make them susceptible to tearing or complete rupture. The present standard reparative technique is the surgical implantation of auto- or allografts, which often undergo failure.Currently, different cell types and biomaterials are used to design tissue engineered substitutes. Mechanical stimulation driven by dedicated devices can precondition these constructs to a remarkable degree, mimicking the local in vivo environment. A large number of dynamic culture instruments have been developed and many appealing results collected. Of the cells that have been used, tendon stem cells are the most promising for a reliable stretch-induced tenogenesis, but their reduced availability represents a serious limitation to upscaled production. Biomaterials used for scaffold fabrication include both biological molecules and synthetic polymers, the latter being improved by nanotechnologies which reproduce the architecture of native tendons. In addition to cell type and scaffold material, other variables which must be defined in mechanostimulation protocols are the amplitude, frequency, duration and direction of the applied strain. The ideal conditions seem to be those producing intermittent tension rather than continuous loading. In any case, all physical parameters must be adapted to the specific response of the cells used and the tensile properties of the scaffold. Tendon/ligament grafts in animals usually have the advantage of mechanical preconditioning, especially when uniaxial cyclic forces are applied to cells engineered into natural or decellularized scaffolds. However, due to the scarcity of in vivo research, standard protocols still need to be defined for clinical applications.

  3. Heel pain-plantar fasciitis and Achilles enthesopathy.

    PubMed

    Williams, Seth K; Brage, Michael

    2004-01-01

    Plantar fasciitis and Achilles enthesopathy are two of the most common causes of posterior heel pain. In the vast majority of cases, nonsurgical treatment methods are effective. In recalcitrant cases, surgery has been shown to be generally effective. There are a variety of described techniques for both conditions. Endoscopic treatment of plantar fasciitis leads to slightly enhanced recovery times compared with the traditional open release, but in the long term the results seem to be equivalent. Open debridement of the retrocalcaneal bursa, calcaneal osteophyte, and diseased tendon is the underlying principle behind surgical treatment of Achilles enthesopathy. This can be performed through a variety of approaches, and augmentation with suture anchors, tendon transfers, or allograft may be necessary when more than 50% of the tendon is excised.

  4. Multiple tendon xanthomas in patient with heterozygous familial hypercholesterolaemia: sonographic and MRI findings

    PubMed Central

    Dagistan, Emine; Canan, Arzu; Kizildag, Betul; Barut, Abdullah Yuksel

    2013-01-01

    Tendon xanthomas are a component of familial hypercholesterolaemia, which is a hereditary disease and characterised by elevated low-density lipo protein cholesterol plasma levels and premature coronary artery disease. Tendon xanthomas are diagnostic for heterozygous familial hypercholesterolaemia (HFH) and they mostly occur in Achilles tendon. Sonography and MRI are superior to clinical assessment and are useful in detecting tendon xanthomas. In this report, we present ultrasonographic and MRI findings of multiple tendon xanthomas in a case of HFH. PMID:24252837

  5. Low intensity pulsed ultrasound increases the mechanical properties of the healing tissues at bone-tendon junction.

    PubMed

    Lu, Min-Hua; Zheng, Yong-Ping; Huang, Qing-Hua; Lu, Hong-Bin; Qin, Ling

    2009-01-01

    The re-establishment of bone-tendon junction (BTJ) tissues is involved in many trauma and reconstructive surgeries. A direct BTJ repair requires a long period of immobilization which may be associated with a postoperative weak knee. In this study, we investigated if low-intensity pulsed ultrasound treatment increases the material properties of healing tissues at bone-tendon junction (BTJ) after partial patellectomy using rabbit models. Standard partial patellectomy was conducted on one knee of twenty four rabbits which were randomly divided into an ultrasound group and a control group. The bony changes of BTJ complexes around the BTJ healing interface were measured by anteroposterior x-ray radiographs; then the volumetric bone-mineral density (BMD) of the new bone was assessed using a peripheral computed tomography scanner (pQCT). The stiffness of patellar cartilage, fibrocartilage at the healing interface and the tendon were measured in situ using a novel noncontact ultrasound water jet indentation system. Not only significantly more newly formed bone at the BTJ healing interface but also increased stiffness of the junction tissues were found in the ultrasound group compared with the controls at week 18. In addition, the ultrasound group also showed significantly 44% higher BMD at week 6 than controls.

  6. Design and characterization of an injectable tendon hydrogel: a novel scaffold for guided tissue regeneration in the musculoskeletal system.

    PubMed

    Farnebo, Simon; Woon, Colin Y L; Schmitt, Taliah; Joubert, Lydia-Marie; Kim, Maxwell; Pham, Hung; Chang, James

    2014-05-01

    A biocompatible hydrogel consisting of extracellular matrix (ECM) from human tendons is described as a potential scaffold for guided tissue regeneration and tissue engineering purposes. Lyophilized decellularized tendons were milled and enzymatically digested to form an ECM solution. The ECM solution properties are assessed by proteome analysis with mass spectrometry, and the material's rheological properties are determined as a function of frequency, temperature, and time. In vivo application of the gel in a rat model is assessed for remodeling and host cell repopulation. Histology for macrophage invasion, fibroblast repopulation, and nanoscale properties of the gel is assessed. Gel interaction with multipotent adipoderived stem cells (ASCs) is also addressed in vitro to assess possible cytotoxicity and its ability to act as a delivery vehicle for cells. Proteome analysis of the ECM-solution and gel mass spectroscopy identified the most abundant 150 proteins, of which two isoforms of collagen I represented more than 55% of the sample. Rheology showed that storage (G') and loss (G″) of the ECM solution were stable at room temperature but displayed sigmoidal increases after ∼15 min at 37°C, matching macroscopic observations of its thermo responsiveness. G' and G″ of the gel at 1 rad/s were 213.1±19.9 and 27.1±2.4 Pa, respectively. Electron microscopy revealed fiber alignment and good structural porosity in the gel, as well as invasion of cells in vivo. Histology also showed early CD68(+) macrophage invasion throughout the gel, followed by increasing numbers of fibroblast cells. ASCs mixed with the gel in vitro proliferated, indicating good biocompatibility. This ECM solution can be delivered percutaneously into a zone of tendon injury. After injection, the thermoresponsive behavior of the ECM solution allows it to polymerize and form a porous gel at body temperature. A supportive nanostructure of collagen fibers is established that conforms to the three

  7. Ultrasound-Based Tendon Micromorphology Predicts Mechanical Characteristics of Degenerated Tendons.

    PubMed

    Kulig, Kornelia; Chang, Yu-Jen; Winiarski, Slawomir; Bashford, Gregory R

    2016-03-01

    The purpose of this study was to explore the relationship between tendon micro-morphology quantified from a sonogram and tendon mechanical characteristics measured in vivo. Nineteen adults (nine with unilateral Achilles tendinosis) participated. A commercial ultrasound scanner was used to capture longitudinal B-mode ultrasound images from the mid-portion of bilateral Achilles tendons and a custom image analysis program was used to analyze the spatial frequency content of manually defined regions of interest; in particular, the average peak spatial frequency of the regions of interest was acquired. In addition, a dynamometer and a motion analysis system indirectly measured the tendon mechanical (stiffness) and material (elastic modulus) properties. The peak spatial frequency correlated with tendon stiffness (r = 0.74, p = 0.02) and elastic modulus (r = 0.65, p = 0.05) in degenerated tendons, but not healthy tendons. This is the first study relating the mechanical characteristics of degenerated human Achilles tendon using a non-invasive micro-morphology analysis approach.

  8. Asymptomatic Achilles, patellar, and quadriceps tendinopathy: a longitudinal clinical and ultrasonographic study in elite fencers.

    PubMed

    Giombini, A; Dragoni, S; Di Cesare, A; Di Cesare, M; Del Buono, A; Maffulli, N

    2013-06-01

    Lower limb tendon changes detected at imaging are common among asymptomatic athletes. We aimed to prospectively assess the clinical status, tendon structure, and vascularity of lower limb tendons of elite fencers, and predict the risk of developing symptoms over time. Clinical examination, changes at ultrasonography (US), and Power Doppler (PD) flow of both the Achilles, patellar, and quadriceps tendon were assessed in 37 elite fencers in January 2007 and 3 years after. Two hundred and twenty-two tendons were examined. At the last appointment, patellar tendons diagnosed as abnormal at baseline were more likely to develop symptoms than those normal at baseline (P < 0.05, Fisher's exact test), while US and PD abnormalities on Achilles and quadriceps tendons were no predictive for development of symptoms over years. A very low percentage of tendons diagnosed as normal at baseline (1.45%) showed US abnormalities at 3-year follow-up. In asymptomatic elite fencers, structural changes are relatively common at US and PD assessment of Achilles, quadriceps, and patellar tendons. It seems unlikely that additional PD investigations provide further information or change prognosis in patients with US diagnosis of tendinopathy.

  9. Photoacoustic microscopy of collagenase-induced Achilles tendinitis in a mouse model

    NASA Astrophysics Data System (ADS)

    Wang, Po-Hsun; Chen, Wen-Shiang; Li, Meng-Lin

    2010-02-01

    Assessments of vascularity are important when assessing inflammation changes in tendon injuries since Achilles tendinitis is often accompanied with neovascularization or hypervascularity. In this study, we have investigated the feasibility of photoacoustic imaging in noninvasive monitoring of morphological and vascular changes in Achilles tendon injuries. Collagenase-induced Achilles tendinitis model of mice was adopted here. During collagenase-induced tendinitis, a 25-MHz photoacoustic microscopy (PAM) was used to image micro-vascular changes in Achilles tendons longitudinally up to 23 days. The positions of vessels imaged by PAM were identified by co-registration of PAM Bmode images with 25-MHz ultrasound (USM) ones. Morphological changes in Achilles tendons due to inflammation and edema were revealed by the PAM and USM images. Proliferation of new blood vessels within the tendons was also observed. Observed micro-vascular changes during tendinitis were similar to the findings in the literatures. This study demonstrates that photoacoustic imaging, owning required sensitivity and penetration, has the potential for high sensitive diagnosis and assessment of treatment performance in tendinopathy.

  10. Investigating backward scattered second harmonic generation from various mouse collagen tissues

    NASA Astrophysics Data System (ADS)

    Shen, Mengzhe; Tian, Yunxian; Chong, Shau Poh; Zhao, Jianhua; Zeng, Haishan; Tang, Shuo

    2014-02-01

    A confocal multiphoton microscopy system with various detection pinholes was used to differentiate backward scattered second harmonic generation (BS-SHG) from backward generated SHG (BG-SHG) based on the fact that BS-SHG is more scattered and therefore has a much bigger spot size than BG-SHG. BS-SHG is quantified from two types of mouse tissues, such as Achilles tendon, and skin, and at various focal depths. It is found that the BS-SHG contributes less to the total backward SHG for the skin than Achilles tendon with thicknesses of around three hundred micrometers. For tissue with larger F/B intensity ratio such as Achilles tendon, increasing the tissue thickness reduces it tremendously. However, for tissue with smaller F/B intensity ratio, tissue thickness increment does not alter it significantly. In addition, larger F/B intensity ratio might be related with a greater scattering coefficient from our Achilles tendon and skin comparison. When the focal point is moved deeper into tissue, the contribution of BS-SHG is found to decrease due to a reduced pass length of the forward propagated photons. On the contrary, when the tissue thickness increases, the contribution of the BS-SHG is increased. These observations for thicker skin tissues are related with our F/B intensity ratio measurement for thin mouse skin sample in terms of that the magnitude of backward generated SHG are dominant among the total backward SHG in mouse skin tissue. Considering the phase mismatching condition in the forward and backward directions, these results may indicate that quasi-phase matching originating from the regular structure of collagen could help with reducing the phase mismatch especially in the backward direction.

  11. Surgical tip: Repair of acute Achilles rupture with Krackow suture through a 1.5 cm medial wound.

    PubMed

    Lui, T H

    2010-03-01

    Acute Achilles tendon ruptures is one of the commonest tendon injury of the foot and ankle. The management of this problem is still controversial. Treatment can be classified into non-surgical and surgical types. Surgical management can be subdivided into open repair, percutaneous with or without adjunct of arthroscopy. In compare with non-surgical management, surgical management will decrease the tendon re-rupture rate. However, the possible surgical complications including wound breakdown and sural nerve injury are still quite significant. Percutaneous repair technique has the advantage of less chance of wound breakdown, but the rate of tendon re-rupture is higher than that after open tendon repair, because the repair is usually weaker than that achieved in open repair. Lui have described an endoscopic assisted repair with the Krackow locking suture. However, the technique is complicated and six portal wounds are needed. A simpler way of applying the Krackow suture through the portal wound has been described for reattachment of Achilles tendon insertion after endoscopic calcaneoplasty. We describe a mini-open approach of Achilles tendon repair with the Krackow locking suture. By means of release of the medial edge of the investing fascia, the Achilles tendon can be mobilized easily and the Krackow locking suture can be applied through a 1.5cm medial wound. Hopefully, this can improve the strength of repair and maintaining the advantage of minimally invasive tendon repair.

  12. A treatment algorithm for managing Achilles tendinopathy: new treatment options

    PubMed Central

    Alfredson, Håkan; Cook, J

    2007-01-01

    Achilles tendinopathy affects athletes, recreational exercisers and even inactive people. The pathology is not inflammatory; it is a failed healing response. The source of pain in tendinopathy could be related to the neurovascular ingrowth seen in the tendon's response to injury. The treatment of Achilles tendinopathy is primarily conservative with an array of effective treatment options now available to the primary care practitioner. If conservative treatment is not successful, then surgery relieves pain in the majority of cases. Directing a patient through the algorithm presented here will maximise positive treatment outcomes. PMID:17311806

  13. Fibrillins in Tendon

    PubMed Central

    Giusti, Betti; Pepe, Guglielmina

    2016-01-01

    Tendons among connective tissue, mainly collagen, contain also elastic fibers (EF) made of fibrillin 1, fibrillin 2 and elastin that are broadly distributed in tendons and represent 1–2% of the dried mass of the tendon. Only in the last years, studies on structure and function of EF in tendons have been performed. Aim of this review is to revise data on the organization of EF in tendons, in particular fibrillin structure and function, and on the clinical manifestations associated to alterations of EF in tendons. Indeed, microfibrils may contribute to tendon mechanics; therefore, their alterations may cause joint hypermobility and contractures which have been found to be clinical features in patients with Marfan syndrome (MFS) and Beals syndrome. The two diseases are caused by mutations in genes FBN1 and FBN2 encoding fibrillin 1 and fibrillin 2, respectively. PMID:27812333

  14. Diagnostic performance of axial-strain sonoelastography in confirming clinically diagnosed Achilles tendinopathy: comparison with B-mode ultrasound and color Doppler imaging.

    PubMed

    Ooi, Chin Chin; Schneider, Michal Elisabeth; Malliaras, Peter; Chadwick, Martine; Connell, David Alister

    2015-01-01

    This primary aim of this study was to evaluate the diagnostic performance of axial-strain sonoelastography (ASE), B-mode ultrasound (US) and color Doppler US in confirming clinically symptomatic Achilles tendinopathy. The secondary aim was to establish the relationship between the strain ratio during sonoelastography and Victorian Institute of Sport Assessment-Achilles (VISA-A) scores. The VISA-A questionnaire is a validated clinical rating scale that evaluates the symptoms and dysfunction of the Achilles tendon. One hundred twenty Achilles tendons of 120 consecutively registered patients with clinical symptoms of Achilles tendinopathy and another 120 gender- and age-matched, asymptomatic Achilles tendons of 120 healthy volunteers were assessed with B-mode US, ASE and color Doppler US. Symptomatic patients had significantly higher strain ratio scores and softer Achilles tendon properties compared with controls (p < 0.001). The strain ratio was moderately correlated with VISA-A scores (r = -0.62, p < 0.001). The diagnostic accuracy of B-mode US, ASE and color Doppler US in confirming clinically symptomatic Achilles tendinopathy was 94.7%, 97.8% and 82.5% respectively. There was excellent correlation between the clinical reference standard and the grade of tendon quality on ASE (κ = 0.91, p < 0.05), compared with B-mode US (κ = 0.74, p < 0.05) and color Doppler imaging (κ = 0.49, p < 0.05). ASE is an accurate clinical tool in the evaluation of Achilles tendinopathy, with results comparable to those of B-mode US and excellent correlation with clinical findings. The strain ratio may offer promise as a supplementary tool for the objective evaluation of Achilles tendon properties.

  15. Gliding characteristics between flexor tendons and surrounding tissues in the carpal tunnel: a biomechanical cadaver study.

    PubMed

    Zhao, Chunfeng; Ettema, Anke M; Osamura, Naoki; Berglund, Lawrence J; An, Kai-Nan; Amadio, Peter C

    2007-02-01

    The purpose of this study was to investigate the gliding characteristics of flexor tendons within the carpal tunnel with varied wrist positions and tendon motion styles, which may help us to understand the relationship between carpal tunnel syndrome (CTS) and repetitive hand motion. Eight fresh human cadaveric wrists and hands were used. The peak (PGR) and mean (MGR) gliding resistance of the middle finger flexor digitorum superficialis tendon were measured with the wrist in 0, 30, and 60 degrees of flexion and extension. While moving all three fingers together, the PGR at 60 degrees flexion was significantly higher than that at 0, 30, or 60 degrees extension. While moving the middle finger alone, the PGR at 60 and 30 degrees flexion was significantly higher than the PGR at 60 degrees extension. The PGR moving the middle finger FDS alone was significantly greater than that for all three digits moving together in 0, 30, and 60 degrees flexion. Differential finger motion with wrist flexion elevated the tendon gliding resistance in the carpal tunnel, which may be relevant in considering the possible role of wrist position and activity in the etiology of CTS.

  16. Achilles tendinopathy: A review of the current concepts of treatment.

    PubMed

    Roche, A J; Calder, J D F

    2013-10-01

    The two main categories of Achilles tendon disorder are broadly classified by anatomical location to include non-insertional and insertional conditions. Non-insertional Achilles tendinopathy is often managed conservatively, and many rehabilitation protocols have been adapted and modified, with excellent clinical results. Emerging and popular alternative therapies, including a variety of injections and extracorporeal shockwave therapy, are often combined with rehabilitation protocols. Surgical approaches have developed, with minimally invasive procedures proving popular. The management of insertional Achilles tendinopathy is improved by recognising coexisting pathologies around the insertion. Conservative rehabilitation protocols as used in non-insertional disorders are thought to prove less successful, but such methods are being modified, with improving results. Treatment such as shockwave therapy is also proving successful. Surgical approaches specific to the diagnosis are constantly evolving, and good results have been achieved.

  17. Utility of Ultrasonography in Assessing the Effectiveness of Extracorporeal Shock Wave Therapy in Insertional Achilles Tendinopathy

    PubMed Central

    Zhang, Jian

    2016-01-01

    Introduction. The aim of this study was to investigate the utility of ultrasonography (US) for predicting and assessing the effectiveness of extracorporeal shock wave therapy (ESWT) in insertional Achilles tendinopathy (IAT). Methods. A total of 42 patients with an established diagnosis of chronic IAT were examined by US before ESWT and at 4 weeks and 12 weeks after ESWT. The thickness and cross-sectional area (CSA) of the Achilles tendon, size of calcific plaques, tendon structure score, and neovascularization score were measured at each time point. Results. After therapy, Victorian Institute of Sport Assessment-Achilles (VISA-A) scores increased significantly, and the size of calcific plaques decreased (P < 0.05). Neovascularization scores increased at the 4th week and then decreased at the 12th week (P < 0.05). The thickness, CSA, and structure of the Achilles tendon did not change. Variables observed by US at baseline were not associated with changes in VISA-A scores at follow-up. However, the changes in calcific plaque size and neovascularization scores were related to the improvement of VISA-A scores between pre- and posttherapy (P < 0.01). Conclusion. Ultrasonography can reveal some changes in the insertion of the Achilles tendon after ESWT, but the outcome of ESWT in IAT cannot be predicted by the variables observed by US. PMID:28004000

  18. Regulation of tendon differentiation by scleraxis distinguishes force-transmitting tendons from muscle-anchoring tendons.

    PubMed

    Murchison, Nicholas D; Price, Brian A; Conner, David A; Keene, Douglas R; Olson, Eric N; Tabin, Clifford J; Schweitzer, Ronen

    2007-07-01

    The scleraxis (Scx) gene, encoding a bHLH transcription factor, is expressed in the progenitors and cells of all tendon tissues. To determine Scx function, we produced a mutant null allele. Scx-/- mice were viable, but showed severe tendon defects, which manifested in a drastically limited use of all paws and back muscles and a complete inability to move the tail. Interestingly, although the differentiation of all force-transmitting and intermuscular tendons was disrupted, other categories of tendons, the function of which is mainly to anchor muscles to the skeleton, were less affected and remained functional, enabling the viability of Scx-/- mutants. The force-transmitting tendons of the limbs and tail varied in the severity to which they were affected, ranging from dramatic failure of progenitor differentiation resulting in the loss of segments or complete tendons, to the formation of small and poorly organized tendons. Tendon progenitors appeared normal in Scx-/- embryos and a phenotype resulting from a failure in the condensation of tendon progenitors to give rise to distinct tendons was first detected at embryonic day (E)13.5. In the tendons that persisted in Scx-/- mutants, we found a reduced and less organized tendon matrix and disorganization at the cellular level that led to intermixing of tenocytes and endotenon cells. The phenotype of Scx-/- mutants emphasizes the diversity of tendon tissues and represents the first molecular insight into the important process of tendon differentiation.

  19. Conservative management of Achilles Tendinopathy: a case report

    PubMed Central

    Papa, John A.

    2012-01-01

    Objective: To chronicle the conservative treatment and management of a 77-year old female patient presenting with chronic pain of 8 months duration in the midportion of the achilles tendon diagnosed as achilles tendinopathy. Clinical features: The main clinical feature was pain in the midportion of the achilles tendon, 2 to 6 cm proximal to the calcaneal insertion. Symptom onset was gradual and unrelated to any acute trauma or overt injury mechanism. Intervention and outcome: The conservative treatment approach consisted of medical acupuncture with electrical stimulation, Graston Technique®, eccentric calf training, and rehabilitative exercise prescription. Outcome measures included verbal pain rating scale, lower extremity functional scale (LEFS), and a return to activities of daily living (ADLs). The patient attained long-term resolution of her complaint and at 12 month follow-up reported no recurrence of symptoms. Conclusion: A combination of conservative rehabilitation strategies may be used by chiropractors to treat midportion achilles tendinopathy and allow an individual to return to pain free ADLs in a timely manner. PMID:22997472

  20. Case report: can sacroiliac joint dysfunction cause chronic Achilles tendinitis?

    PubMed

    Voorn, R

    1998-06-01

    This case study discusses the possible relationship between chronic Achilles tendinitis and sacroiliac joint dysfunction. The patient presented is an active pole jumper, competing at both the national and international levels. He suffered from chronic Achilles tendinitis during the 1994-95 season, and conservative treatment applied locally was not successful. The athlete discarded the possibility of operative debridement of the tendon. Instead, an evaluation of the kinetic chain of the lower extremity and pelvic-lumbar area was performed, and the athlete was diagnosed with sacroiliac joint dysfunction and Achilles tendinitis. Evaluation findings, treatment program, and treatment outcome are also presented. The literature regarding sacroiliac joint mechanics and biomechanics of the foot-knee-hip and pelvic area is discussed and used to support the author's thesis that sacroiliac joint dysfunction, in this case a backward rotation of the right ilium, may have changed the kinematic chain of the lower extremity and caused a tendinitis in the Achilles tendon of the affected leg. Sacroiliac joint function and dysfunction, the reliability of sacroiliac joint mobility tests, and the validity of treatment programs are still considered controversial, and more research is needed to understand these mechanisms.

  1. Tendonitis (image)

    MedlinePlus

    ... tendon. It can occur as a result of injury, overuse, or with aging as the tendon loses elasticity. Any action that places prolonged repetitive strain on the forearm muscles can cause tendonitis. The ...

  2. Platelet-rich plasma: evidence for the treatment of patellar and Achilles tendinopathy--a systematic review.

    PubMed

    Di Matteo, B; Filardo, G; Kon, E; Marcacci, M

    2015-04-01

    Platelet-rich plasma (PRP) has been introduced in the clinical practice to treat a growing number of different musculoskeletal pathologies. It is currently applied in the treatment of Achilles and patellar tendinopathies, which are common sport-related injuries very challenging to manage. Aim of the present paper was to review systematically the available clinical evidence concerning the application of PRP in the treatment of patellar and Achilles tendinopathy. A systematic review of the literature was performed according to the following inclusion criteria for relevant articles: (1) clinical reports of any level of evidence, (2) written in the English language, (3) with no time limitation and (4) on the use of PRP to treat conservatively Achilles and patellar tendinopathy. Twenty-two studies were included and analyzed. Two studies on patellar tendinopathy were randomized controlled trials (RCTs), whereas just one RCT was published on Achilles tendon. All the papers concerning patellar tendon reported positive outcome for PRP, which proved to be superior to other traditional approaches such as shock-wave therapy and dry needling. In the case of Achilles tendon, despite the encouraging findings reported by case series, the only RCT available showed no significant clinical difference between PRP and saline solution. The main finding of this study was the paucity of high-level literature regarding the application of PRP in the management of patellar and Achilles tendinopathy. However, the clinical data currently available, although not univocal, suggest considering PRP as a therapeutic option for recalcitrant patellar and Achilles tendinopathies.

  3. Effects of Growth on Muscle, Tendon, and Aponeurosis Tissues in Rabbit Shank Musculature.

    PubMed

    Böl, Markus; Leichsenring, Kay; Siebert, Tobias

    2016-12-20

    There exist several studies using morphological analyses of skeletal muscles to obtain a better understanding of muscle structure. The structural information obtained are primarily determined from single muscle components using individual animals of discrete ages. Further, little is known about changing dimensions of the aponeurosis, which is an important load-transferring interface in muscle mechanics. Thus, the aim of the present study was to determine how the muscle, tendon, and particularly the aponeurosis geometry of the rabbit shank musculature (M. soleus, M. extensor digitorum longus, and M. plantaris) change during growth. In doing so, morphological studies on muscles of eighty-nine female rabbits aged between 18 and 108 days were conducted. We found an almost linear increase over time in all of the geometrical parameters observed. The aponeurosis of the muscles exhibited lower growth rates in width than in length. The distal and proximal aponeurosis areas were nearly identical. The ratio of aponeurosis area to the physiological cross-sectional area was 2.54, 2.54, and 1.88 for M. soleus, M. extensor digitorum longus, and M. plantaris, respectively. M. extensor digitorum longus and M. soleus exhibited a nearly similar tendon-muscle fascicle length ratio during growth, increasing from 2.86 to 5.30 and 3.48 to 6.16, respectively. Interestingly, the tendon-muscle fascicle length ratio of the M. plantaris started initially with a much higher value (∼8) and increased to ∼18. Taken together, these results provide insight into the structure of the muscle-tendon complex and thus, a general understanding of muscle growth. Anat Rec, 2016. © 2016 Wiley Periodicals, Inc.

  4. Anisotropy of the transverse mode ultrasonic properties of fixed tendon and fixed myocardium.

    PubMed

    Hoffmeister, B K; Gehr, S E; Miller, J G

    1996-06-01

    This study investigates the influence of the fiber-reinforced nature of myocardium and tendon on the propagation of transverse mode ultrasonic waves. Formalin fixed specimens of normal human left ventricular cardiac muscle and bovine Achilles tendon were prepared for this study in such a way that transverse mode ultrasonic waves could be propagated perpendicular to the fiber axis of the tissue with the polarization oriented either parallel or perpendicular to the fiber axis. Measurements of velocity and attenuation were made at 3 MHz to assess the degree of anisotropy in these parameters for both tissues. Formalin fixed tendon exhibited a significant anisotropy whereas formalin fixed myocardium displayed a similar trend of more modest magnitude. Results of these measurements were used to compute two elastic stiffness coefficients for each tissue, yielding c44 = 37.2 MPa and c66 = 18.0 MPa for formalin fixed tendon, and c44 = 8.97 MPa and c66 = 8.45 MPa for formalin fixed myocardium. To validate this approach, additional studies were conducted to measure the transverse mode ultrasonic properties of silicone rubber and motor oil.

  5. Varying whole body vibration amplitude differentially affects tendon and ligament structural and material properties.

    PubMed

    Keller, Benjamin V; Davis, Matthew L; Thompson, William R; Dahners, Laurence E; Weinhold, Paul S

    2013-05-31

    Whole Body Vibration (WBV) is becoming increasingly popular for helping to maintain bone mass and strengthening muscle. Vibration regimens optimized for bone maintenance often operate at hypogravity levels (<1G) and regimens for muscle strengthening often employ hypergravity (>1G) vibrations. The effect of vibratory loads on tendon and ligament properties is unclear though excessive vibrations may be injurious. Our objective was to evaluate how tendon gene expression and the mechanical/histological properties of tendon and ligament were affected in response to WBV in the following groups: no vibration, low vibration (0.3G peak-to-peak), and high vibration (2G peak-to-peak). Rats were vibrated for 20 min a day, 5 days a week, for 5 weeks. Upon sacrifice, the medial collateral ligament (MCL), patellar tendon (PT), and the Achilles Tendon (AT) were isolated with insertion sites intact. All tissues were tensile tested to determine structural and material properties or used for histology. Patellar tendon was also subjected to quantitative RT-PCR to evaluate expression of anabolic and catabolic genes. No differences in biomechanical data between the control and the low vibration groups were found. There was evidence of significant weakness in the MCL with high vibration, but no significant effect on the PT or AT. Histology of the MCL and PT showed a hypercellular tissue response and some fiber disorganization with high vibration. High vibration caused an increase in collagen expression and a trend for an increase in IGF-1 expression suggesting a potential anabolic response to prevent tendon overuse injury.

  6. Longitudinal Cell Tracking and Simultaneous Monitoring of Tissue Regeneration after Cell Treatment of Natural Tendon Disease by Low-Field Magnetic Resonance Imaging

    PubMed Central

    Berner, Dagmar; Brehm, Walter; Gerlach, Kerstin; Gittel, Claudia; Offhaus, Julia; Paebst, Felicitas; Scharner, Doreen; Burk, Janina

    2016-01-01

    Treatment of tendon disease with multipotent mesenchymal stromal cells (MSC) is a promising option to improve tissue regeneration. To elucidate the mechanisms by which MSC support regeneration, longitudinal tracking of MSC labelled with superparamagnetic iron oxide (SPIO) by magnetic resonance imaging (MRI) could provide important insight. Nine equine patients suffering from tendon disease were treated with SPIO-labelled or nonlabelled allogeneic umbilical cord-derived MSC by local injection. Labelling of MSC was confirmed by microscopy and MRI. All animals were subjected to clinical, ultrasonographical, and low-field MRI examinations before and directly after MSC application as well as 2, 4, and 8 weeks after MSC application. Hypointense artefacts with characteristically low signal intensity were identified at the site of injection of SPIO-MSC in T1- and T2∗-weighted gradient echo MRI sequences. They were visible in all 7 cases treated with SPIO-MSC directly after injection, but not in the control cases treated with nonlabelled MSC. Furthermore, hypointense artefacts remained traceable within the damaged tendon tissue during the whole follow-up period in 5 out of 7 cases. Tendon healing could be monitored at the same time. Clinical and ultrasonographical findings as well as T2-weighted MRI series indicated a gradual improvement of tendon function and structure. PMID:26880932

  7. Longitudinal Cell Tracking and Simultaneous Monitoring of Tissue Regeneration after Cell Treatment of Natural Tendon Disease by Low-Field Magnetic Resonance Imaging.

    PubMed

    Berner, Dagmar; Brehm, Walter; Gerlach, Kerstin; Gittel, Claudia; Offhaus, Julia; Paebst, Felicitas; Scharner, Doreen; Burk, Janina

    2016-01-01

    Treatment of tendon disease with multipotent mesenchymal stromal cells (MSC) is a promising option to improve tissue regeneration. To elucidate the mechanisms by which MSC support regeneration, longitudinal tracking of MSC labelled with superparamagnetic iron oxide (SPIO) by magnetic resonance imaging (MRI) could provide important insight. Nine equine patients suffering from tendon disease were treated with SPIO-labelled or nonlabelled allogeneic umbilical cord-derived MSC by local injection. Labelling of MSC was confirmed by microscopy and MRI. All animals were subjected to clinical, ultrasonographical, and low-field MRI examinations before and directly after MSC application as well as 2, 4, and 8 weeks after MSC application. Hypointense artefacts with characteristically low signal intensity were identified at the site of injection of SPIO-MSC in T1- and T2 (∗) -weighted gradient echo MRI sequences. They were visible in all 7 cases treated with SPIO-MSC directly after injection, but not in the control cases treated with nonlabelled MSC. Furthermore, hypointense artefacts remained traceable within the damaged tendon tissue during the whole follow-up period in 5 out of 7 cases. Tendon healing could be monitored at the same time. Clinical and ultrasonographical findings as well as T2-weighted MRI series indicated a gradual improvement of tendon function and structure.

  8. Tendon vs. ligament (image)

    MedlinePlus

    ... the eyeball. A tendon serves to move the bone or structure. A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable.

  9. Role of xenogenous bovine platelet gel embedded within collagen implant on tendon healing: an in vitro and in vivo study

    PubMed Central

    Oryan, Ahmad; Meimandi-Parizi, Abdolhamid; Maffulli, Nicola

    2015-01-01

    Surgical reconstruction of large Achilles tendon defects is demanding. Platelet concentrates may be useful to favor healing in such conditions. The characteristics of bovine platelet-gel embedded within a collagen-implant were determined in vitro, and its healing efficacy was examined in a large Achilles tendon defect in rabbits. Two cm of the left Achilles tendon of 60 rabbits were excised, and the animals were randomly assigned to control (no implant), collagen-implant, or bovine-platelet-gel-collagen-implant groups. The tendon edges were maintained aligned using a Kessler suture. No implant was inserted in the control group. In the two other groups, a collagen-implant or bovine-platelet-gel-collagen-implant was inserted in the defect. The bioelectricity and serum platelet-derived growth factor levels were measured weekly and at 60 days post injury, respectively. After euthanasia at 60 days post injury, the tendons were tested at macroscopic, microscopic, and ultrastructural levels, and their dry matter and biomechanical performances were also assessed. Another 60 rabbits were assigned to receive no implant, a collagen-implant, or a bovine-platelet-gel-collagen-implant, euthanized at 10, 20, 30, and 40 days post injury, and their tendons were evaluated grossly and histologically to determine host-graft interactions. Compared to the control and collagen-implant, treatment with bovine-platelet-gel-collagen-implant improved tissue bioelectricity and serum platelet-derived growth factor levels, and increased cell proliferation, differentiation, and maturation. It also increased number, diameter, and density of the collagen fibrils, alignment and maturation of the collagen fibrils and fibers, biomechanical properties and dry matter content of the injured tendons at 60 days post injury. The bovine-platelet-gel-collagen-implant also increased biodegradability, biocompatibility, and tissue incorporation behavior of the implant compared to the collagen-implant alone

  10. Relaxin Receptor RXFP1 and RXFP2 Expression in Ligament, Tendon, and Shoulder Joint Capsule of Rats

    PubMed Central

    2016-01-01

    Numerous musculoskeletal disorders are caused by thickened ligament, tendon stiffness, or fibrosis of joint capsule. Relaxin, a peptide hormone, can exert collagenolytic effect on ligamentous and fibrotic tissues. We hypothesized that local injection of relaxin could be used to treat entrapment neuropathy and adhesive capsulitis. Because hormonal effect depends on the receptor of the hormone on the target cell, it is important to confirm the presence of such hormonal receptor at the target tissue before the hormone therapy is initiated. The aim of this study was to determine whether there were relaxin receptors in the ligament, tendon, and joint capsular tissues of rats and to identify the distribution of relaxin receptors in these tissues. Transverse carpal ligaments (TCLs), inguinal ligaments, anterior cruciate ligaments (ACLs), Achilles tendons, and shoulder joint capsules were obtained from male Wistar rats. Western blot analysis was used to identify relaxin receptor isoforms RXFP1 and RXFP2. The distribution of relaxin receptors was determined by immunohistochemical staining. The RXFP1 isoform was found in all tissues examined. The RXFP2 isoform was present in all tissues but the TCLs. Its expression in ACLs tissues was relatively weak compared to that in other tissues. Our results revealed that RXFP1 and RXFP2 were distributed in distinctly different patterns according to the type of tissue (vascular endothelial cells, fibroblast-like cells) they were identified. PMID:27247510

  11. Is percutaneous radiofrequency coblation for treatment of Achilles tendinosis safe and effective?

    PubMed

    Shibuya, Naohiro; Thorud, Jakob C; Humphers, Jon M; Devall, J Marshall; Jupiter, Daniel C

    2012-01-01

    Insertional Achilles tendinosis results in isolated pain at the Achilles tendon insertion site due to intratendinous degeneration. When conservative measures fail, surgical treatment may be necessary. Radiofrequency coblation has been suggested to be an effective procedure for treatment of tendon pathologies. Percutaneous execution of this procedure is very simple as well as minimally invasive, and thus if effective, would be an excellent alternative to an open treatment of insertional Achilles tendinopathy. A review of 47 cases with this percutaneous technique was conducted. In our relatively short-term follow-up (mean = 8.6 months, SD = 9.71, range 1 to 40), the incidence of reoperation was 14.9% (7/47). Rupture of the Achilles tendon was identified in 3 (6.4%) patients. Our cohort had a relatively high body mass index (mean = 37.1, SD = 6.96, range 24.3 to 52.8). We recommend surgeons to be cautious about selecting this procedure in similar, high body mass index patient cohorts for treatment of Achilles tendinosis.

  12. Neuronal regulation of tendon homoeostasis.

    PubMed

    Ackermann, Paul W

    2013-08-01

    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.

  13. 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

  14. Connective tissue polarity. Optical second-harmonic microscopy, crossed-beam summation, and small-angle scattering in rat-tail tendon.

    PubMed Central

    Freund, I; Deutsch, M; Sprecher, A

    1986-01-01

    Connective tissue polarity has remained an intractable enigma for over two decades. We present new data on optical second harmonic generation in native, wet, rat-tail tendon. Scanning second-harmonic microscopy has revealed, for the first time, the existence of a discrete network of fine, polar, filamentous or columnar, structures, and, also, the presence of strongly polar surface, or near-surface patches. The thickness of these features was probed via crossed-beam optical frequency summation and the polar material is estimated to occupy a few percent of the tendon volume. The three-dimensional spatial distribution of filaments was studied with the aid of small-angle second-harmonic scattering, and the filaments were found to permeate the tendon cross-section in an apparently random fashion. These latter measurements also revealed that essentially all polar filaments had the same directionality. Concomitant studies of the polar collagen fibrils that comprise the bulk of tendon were in full accord with prior electron microscope results that had demonstrated that the directionality of these fibrils varies up/down in a purely random fashion, and thus cannot yield a net macroscopic polarity. Quantitative analysis of the second-harmonic data yields the conclusion that the observed polar structures cannot be simply local regions containing some accidental net excess of similarly oriented fibrils. The analytical expressions used in the analysis of the data obtained for this complex tissue were supported by extensive, realistic computer simulations. The discovery that the polarity of rat-tail tendon, and possibly other forms of connective tissue, resides in discrete structures, some of which are located near the tendon surface, should permit the ready isolation of polar-rich material for further study by a variety of techniques. Images FIGURE 2 PMID:3779007

  15. Metabolic syndrome associated to non-inflammatory Achilles enthesopathy.

    PubMed

    Abate, Michele; Di Carlo, Luigi; Salini, Vincenzo; Schiavone, Cosima

    2014-01-01

    Enthesopathies are frequently found in rheumatic inflammatory diseases, but can be observed also in absence of systemic inflammation. Aging, overuse, and microtraumas can be responsible for enthesis-degenerative phenomena. Despite that Achilles enthesis is the more frequently affected, no systematic study on the risk factors associated to this enthesopathy has been yet performed. The aim of this paper was to assess whether the metabolic syndrome could be associated to entheseal lesions. Forty-five subjects with symptomatic non-inflammatory Achilles enthesopathy were compared to 45 asymptomatic controls. An ultrasound study of the Achilles enthesis was carried out, and the presence/absence of lesions (morphologic abnormalities, calcific deposits, enthesophytes, cortical abnormalities, and adjacent bursitis) was assessed. On the basis of history, comorbidities (osteoarthritis, diabetes, and hypertension) were recorded. In each subject, body mass index (BMI), glucose, total, and HDL cholesterol were also evaluated. All symptomatic subjects showed at ultrasound evaluation at least one structural entheseal alteration; pathologic features in asymptomatic subjects were found in 6/45 (13.3 %) of cases. Higher values of BMI and glucose were found in subjects with symptomatic enthesopathy. At multiple logistic regression analysis, the presence of high values of BMI and glucose was related to a higher probability to detect entheseal lesions. Metabolic syndrome and overweight may have a role in the pathogenesis of Achilles enthesopathy due to their synergistic worsening effect on other pathogenetic factors of tendon degeneration, such age and overuse. Therefore, subjects with metabolic syndrome practicing sports and other activities stressing the Achilles tendon should receive advice for more frequent controls.

  16. Preparation of ready-to-use, storable and reconstituted type I collagen from rat tail tendon for tissue engineering applications.

    PubMed

    Rajan, Navneeta; Habermehl, Jason; Coté, Marie-France; Doillon, Charles J; Mantovani, Diego

    2006-01-01

    Collagen is a widely investigated extracellular matrix material with extensive potentials in the field of tissue engineering. This protocol describes a method to prepare reconstituted collagen that can be ready-to-use, storable and suitable for further in vitro and in vivo investigations. Type I collagen was extracted from rat tail tendons and processed in acetic acid solution to obtain sterile soluble collagen. At first, crude collagen was dissolved in acetic acid, then frozen at -20 degrees C and lyophilized to obtain a sponge, which could be stored at -80 degrees C. Lyophilized collagen was then dispersed in acetic acid to obtain a sterile solution of collagen at targeted concentrations. The whole low-cost process from the extraction to the final sterile solution takes around 2-3 weeks. The collagen solution, once neutralized, has the potential to be used to produce gels or scaffolds, to deposit thin films on supports and to develop drug delivery systems.

  17. Technical Innovation Case Report: Ultrasound-Guided Prolotherapy Injection for Insertional Achilles Calcific Tendinosis

    PubMed Central

    DeLuca, Jesse P.; Lammlein, Kyle P.

    2016-01-01

    We describe the use of ultrasound guidance for hyperosmolar dextrose (prolotherapy) injection of the distal calcaneal tendon specifically just anterior to identified enthesophytes in patients with insertional Achilles calcific tendinosis refractory to conservative treatment. This specific technique has not to our knowledge been described or used in literature previously. PMID:27974984

  18. Tendon and Ligament Regeneration and Repair: Clinical Relevance and Developmental Paradigm

    PubMed Central

    Tuan, Rocky S.

    2014-01-01

    Tendon and ligament (T/L) are dense connective tissues connecting bone to muscle and bone to bone, respectively. Similar to other musculoskeletal tissues, T/L arise from the somitic mesoderm, but they are derived from a recently discovered somitic compartment, the syndetome. The adjacent sclerotome and myotome provide inductive signals to the interposing syndetome, thereby upregulating the expression of the transcription factor Scleraxis, which in turn leads to further tenogenic and ligamentogenic differentiation. These advances in the understanding of T/L development have been sought to provide a knowledge base for improving the healing of T/L injuries, a common clinical challenge due to the intrinsically poor natural healing response. Specifically, the three most common tendon injuries involve tearing of the rotator cuff of the shoulder, the flexor tendon of the hand, and the Achilles tendon. At present, injuries to these tissues are treated by surgical repair and/or conservative approaches, including biophysical modalities such as physical rehabilitation and cryotherapy. Unfortunately, the healing tissue forms fibrovascular scar and possesses inferior mechanical and biochemical properties as compared to native T/L. Therefore, tissue engineers have sought to improve upon the natural healing response by augmenting the injured tissue with cells, scaffolds, bioactive agents, and mechanical stimulation. These strategies show promise, both in vitro and in vivo, for improving T/L healing. However, several challenges remain in restoring full T/L function following injury, including uncertainties over the optimal combination of these biological agents as well how to best deliver tissue engineered elements to the injury site. A greater understanding of the molecular mechanisms involved in T/L development and natural healing, coupled with the capability of producing complex biomaterials to deliver multiple growth factors with high spatiotemporal resolution and specificity

  19. Comparison of Lower Limb Muscle Activity during Eccentric and Concentric Exercises in Runners with Achilles Tendinopathy

    PubMed Central

    Yu, Jaeho

    2014-01-01

    [Purpose] This study aimed to identify changes in muscle activation by comparing muscle activities of the affected side (AS) and non-affected side (NAS) during eccentric and concentric exercises in runners with unilateral Achilles tendinopathy. [Subjects] The study included 18 participants consisting of men and women with chronic Achilles tendinopathy in a single leg who had more than 1 year of running experience. [Methods] All subjects performed concentric and eccentric exercise with the Achilles tendon moving from full plantar flexion to full dorsiflexion for 8 seconds, and electromyography data was obtained. [Results] All muscles examined showed a significant increase in %maximal voluntary contraction (MVC) with concentric exercise compared with eccentric exercise. Compared with the NAS, the AS showed significant increases in %MVC of the rectus femoris, tibialis anterior, and lateral gastrocnemius. All interaction effects of exercise methods and injuries showed statistically significant changes. [Conclusion] Runners with Achilles tendinopathy show increases in medial gastrocnemius activity when performing eccentric exercise. PMID:25276014

  20. Imaging of plantar fascia and Achilles injuries undertaken at the London 2012 Olympics.

    PubMed

    Elias, David A; Carne, Andrew; Bethapudi, Sarath; Engebretsen, Lars; Budgett, Richard; O'Connor, Philip

    2013-12-01

    Plantar fascia and distal Achilles injuries are common in elite athletes. Acute athletic injuries of the plantar fascia include acute plantar fasciopathy and partial or complete tears. Underlying most acute injuries is a background of underlying chronic plantar fasciopathy. Injuries may affect the central or less commonly lateral portions of the fascia and acute tears are generally proximal. Athletic Achilles injuries may occur at the mid tendon or the distal insertion, and there may be an underlying chronic tendinopathy. Acute or chronic paratendinopathy may occur as a separate entity or combined with Achilles injury. In this article, the spectrum of athletic injuries of the plantar fascia and Achilles is described, illustrated by imaging findings from the London 2012 Olympic games.

  1. Is calcaneal inclination higher in patients with insertional Achilles tendinosis? A case-controlled, cross-sectional study.

    PubMed

    Shibuya, Naohiro; Thorud, Jakob C; Agarwal, Monica R; Jupiter, Daniel C

    2012-01-01

    Insertional Achilles tendinosis is a condition where a patient complains of isolated pain at the Achilles tendon insertion site due to intratendinous degeneration. It has been suggested that this condition is associated with cavus foot deformity. However, to our knowledge, there is no study that has confirmed this observation. We carried out a cross-sectional, case-controlled study to explore the association of increased calcaneal inclination-a surgically important characteristic of cavus foot deformity-with insertional Achilles tendinosis. Patients with Achilles tendinosis and matched controls without the pathology were compared. Although a statistically significant difference was detected in calcaneal inclination angle between these 2 groups (p = .038), we felt that the difference was not clinically significant (calcaneal inclination angle = 20.9 vs. 18.9, respectively). Within the limitations of the study, we conclude that there is no clinically significant difference in calcaneal inclination between those with or without insertional Achilles tendinosis.

  2. 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

  3. Tissue characteristics in tendon-to-bone healing change after rotator cuff repair using botulinumneurotoxin A for temporary paralysis of the supraspinatus muscle in rats.

    PubMed

    Ficklscherer, A; Scharf, M; Hartl, T K; Schröder, C; Milz, S; Roßbach, B P; Gülecyüz, M F; Pietschmann, M F; Müller, P E

    2014-04-01

    We hypothesized that botulinumneurotoxin A (BoNtA) positively influences tissue characteristics at the re-insertion site when used as an adjuvant prior to rotator cuff repair. One hundred and sixty Sprague-Dawley rats were randomly assigned to either a BoNtA or saline-injected control group. BoNtA or saline solution was injected into the supraspinatus muscle one week prior to repair of an artificially created supraspinatus tendon defect. Post-operatively, one subgroup was immobilized using a cast on the operated shoulder while the other had immediate mobilization. Histologically, the fibrocartilage transition zone was more prominent and better organized in the BoNtA groups when compared to the saline control group. In the immediately mobilized BoNtA groups significantly more collagen 2 at the insertion was detected than in the control groups (p<0.05). Fiber orientation of all BoNtA groups was better organized and more perpendicular to the epiphysis compared with control groups. Tendon stiffness differed significantly (p<0.05) between casted BoNtA and casted saline groups. Tendon viscoelasticity was significantly higher (p<0.05) in the immobilized saline groups no matter if repaired with increased or normal repair load. The results of this study suggest that reduction of load at the healing tendon-to-bone interface leads to improved repair tissue properties.

  4. Peritendinous elastase treatment induces tendon degeneration in rats: A potential model of tendinopathy in vivo.

    PubMed

    Wu, Yen-Ting; Wu, Po-Ting; Jou, I-Ming

    2016-03-01

    The purpose of this study was to investigate the role of elastase on tendinopathy, as well as to evaluate the potential for peritendinous injections of elastase into rats to cause tendinopathy. We first investigated the expression of elastase in the tendons of patients with tendinopathy, and then established the effects of elastase injection on the Achilles tendons of rats. Ultrasonographic and incapacitance testing was used to conduct tests for 8 weeks. Tendon tissues were collected for histological observation and protein levels of collagen type I and type III were detected using Western blotting. The percentage of elastase-positive cells increased in human specimens with grades II and III tendinopathy. The rat model demonstrated that the thickness of the tendon increased after elastase injection during Week 2-8. Hypercellularity and focal lesions were detected after Week 2. The expression of elastase was increased and elastin was decreased in Week 8. Collagen type I expression was decreased, but type III was increased in Week 4. These results suggested that elastase may be involved in the development of chronic tendinopathy, and that peritendinous injection of elastase may result in tendinopathy in rats.

  5. [Guideline 'Chronic Achilles tendinopathy, in particular tendinosis, in sportsmen/sportswomen'].

    PubMed

    van Linschoten, R; den Hoed, P T; de Jongh, A C

    2007-10-20

    --Chronic Achilles tendinopathy in sports often leads to various therapeutic strategies, medical shopping and frequently to inability to perform at the desired level. --Although it is clear that this chronic tendinopathy is not an inflammatory disease of the tendon, the cause of the degeneration of the tendon fibres is not understood. --The main therapeutic measure--based on scientific evidence--is eccentric calf-muscle training for at least 3 months. --Recent therapies such as sclerotherapy ofneovascularizations in and around the Achilles tendon appear to be promising, but more studies are required. --About 20% of the patients tend to be refractive to conservative measures. --In selected cases surgery can be undertaken, with percutaneous longitudinal tenotomy proving effective in 75-80% of the cases.

  6. Sclerosing injections in midportion Achilles tendinopathy: a retrospective study of 25 patients.

    PubMed

    Clementson, Martin; Lorén, Ingemar; Dahlberg, Leif; Aström, Mats

    2008-09-01

    Sclerosing injections under ultrasonographic guidance is a new method of treatment for persistent pain in Achilles tendinosis. Good results, even superior to those of surgery, have been described. We report the outcome of 25 patients with midportion tendinosis receiving sclerosing treatment. Twenty-eight consecutive patients (29 tendons) with ultrasonographical findings of midportion tendinosis examined during the period November 2004 to November 2005 were identified in the database of the Department of Radiology, Malmö University Hospital. Twenty-five patients (26 tendons) were found suitable for treatment. Follow-up consisted of self-assessment questionnaire or phone interview. In 19 patients (20 tendons), results were good or excellent. Complications were few and mild. We conclude that sclerosing injections is a promising alternative to surgery in chronic Achilles midportion tendinosis. Our results are comparable to those obtained with surgery, but the procedure is less invasive. However, a few cases of tendinosis lack detectable neovessels and may still be candidates for surgery.

  7. US imaging in operated tendons.

    PubMed

    Cohen, M

    2012-02-01

    Ultrasound (US) plays an essential role in the follow-up of operated tendons. The US operator must keep in mind three main elements: healing of traumatic injuries of the tendons seems to follow the biological model of histologic healing, surgical repair of a tendon rupture improves the structural parameters of the operated tendon, but it does not grant restitutio ad integrum, and US findings therefore seem poorly correlated with the functional evolution.Before examination, the US operator should be familiar with the nature of the tendon injury that has led to surgery including location, severity, time elapsed between tendon injury and surgical repair, surgical technique, postoperative course and possible complications. US findings in operated as well as non-operated tendons depend on several factors: morphology, structure, vascularization of the tendon, mobility of the tendon and mobility of the peritendinous tissues. Particular features are therefore considered according to the location: shoulder, elbow, wrist, hand, knee, ankle and foot. Interpretation of the US image requires knowledge of the surgical technique and "normal" postoperative appearance of the operated tendon in order to detect pathological findings such as thinning, persistent fluid collections within or around the tendon, persistent hypervascularization, intratendinous calcifications and adhesions.

  8. The traumatic rupture of the Achilles’ tendon – an analysis of the modern methods of evaluation and treatment

    PubMed Central

    BARDAŞ, CIPRIAN; BENEA, HOREA; MARTIN, ARTUR; TOMOAIA, GHEORGHE

    2013-01-01

    Aims The main aim of this article is an analysis of both advantages and disadvantages of the modern solutions of treatment – percutaneous surgery, in comparison with the classic methods of treatments described in the surgery of Achilles’ tendon. Patients and method The study was conducted on 23 patients admitted to the Orthopedics and Traumatology Clinic of Cluj-Napoca between January 2011–June 2012. Nineteen (19) patients were diagnosed with a complete rupture of the Achilles tendon and 4 patients with a partial rupture. The diagnosis of traumatic Achilles tendon ruptures was usually clinical, the Ultrasound (common or 3D) and the MRI confirmed the lesion and determined its location and extension. We analyzed the diagnostic methods, the elapsed time before surgery, the treatment options depending on lesion’s location, technical difficulties, costs, postoperative care, the average healing time, complications. Results The Ultrasound was performed in 65.2% of the patients (15 patients) for confirming the extension of the lesion and it served for pre-operative planning. In most of the cases, the classical methods of Achilles tendon reconstruction were used (18 cases). The complications rate was about 8%. We diagnosed an iterative Achilles tendon rupture (the patient was initially treated using the percutaneous methods) and a delay in cicatrisation. Conclusions The percutaneous surgical techniques are a viable alternative for the acute ruptures of Achilles tendon, the classic intervention has clear indications in lesions diagnosed late, in the recurrent tendon ruptures. PMID:26527933

  9. Treatment of a Complex Distal Triceps Tendon Rupture With a New Technique: A Case Report

    PubMed Central

    Aunon-Martin, Ismael; Prada-Canizares, Alfonso; Jimenez-Diaz, Veronica; Vidal-Bujanda, Carlos; Leon-Baltasar, Jose Luis

    2016-01-01

    Introduction: The distal triceps tendon rupture is an uncommon injury. The acute treatment is well-defined, but when a delayed diagnosis is made or when a tendon retraction is present the alternatives or reconstruction are limited and sometimes complex. Case Presentation: In this case, we report on a 28-year-old man who presented with a chronic disruption of the distal triceps tendon with a gap of approximately 15 cm. The patient was diagnosed in another center with an inveterate breakage of the distal triceps tendon and was initially treated with an Achilles allograft that was complicated by a wound infection and required more than ten surgeries. Nearly 22 months after the initial trauma, and 12 months after the first surgery, we performed a reconstruction with an Achilles tendon allograft using the new technique of distal attachment. At the 12-month follow-up the patient presented a joint balance from -5º to 110º and presented with no pain. Conclusions: The use of an Achilles tendon allograft provides excellent results in complex distal triceps tendon ruptures. We report the use of a new technique to anchor a distal Achilles allograft. PMID:27148500

  10. Famotidine suppresses osteogenic differentiation of tendon cells in vitro and pathological calcification of tendon in vivo.

    PubMed

    Yamamoto, Kenichi; Hojo, Hironori; Koshima, Isao; Chung, Ung-il; Ohba, Shinsuke

    2012-12-01

    Heterotopic ossification or calcification follows any type of musculoskeletal trauma and is known to occur after arthroplasties of hip, knee, shoulder, or elbow; fractures; joint dislocations; or tendon ruptures. Histamine receptor H2 (Hrh2) has been shown to be effective for reducing pain and decreasing calcification in patients with calcifying tendinitis, which suggested that H2 blockers were effective for the treatment of tendon ossification or calcification. However, the detailed mechanisms of its action on tendon remain to be clarified. We investigated the mechanisms underlying H2 blocker-mediated suppression of tendon calcification, with a focus on the direct action of the drug on tendon cells. Famotidine treatment suppressed the mRNA expressions of Col10a1 and osteocalcin, ossification markers, in a tendon-derived cell line TT-D6, as well as a preosteoblastic one MC3T3-E1. Both of the cell lines expressed Hrh2; histamine treatment induced osteocalcin expression in these cells. Famotidine administration suppressed calcification in the Achilles tendon of ttw mice, a mouse model of ectopic ossification. These data suggest that famotidine inhibits osteogenic differentiation of tendon cells in vitro, and this inhibition may underlie the anti-calcification effects of the drug in vivo. This study points to the use of H2 blockers as a promising strategy for treating heterotopic ossification or calcification in tendon, and provides evidence in support of the clinical use of famotidine.

  11. Biomechanical properties of normal tendons, normal palmar aponeuroses, and tissues from patients with Dupuytren's disease subjected to elastase and chondroitinase treatment.

    PubMed

    Millesi, H; Reihsner, R; Hamilton, G; Mallinger, R; Menzel, E J

    1995-01-01

    Normal tendons, normal palmar aponeuroses and palmar aponeuroses from patients with Dupuytren's disease were subjected to elastase or chondroitinase treatment. Young's modulus was derived from the linear portion of stress-strain graph. It showed the lowest value for the apparently normal palmar aponeuroses and the highest value for tendon samples. Elastase treatment caused an increase of extensibility and a reduction of Young's modulus of normal palmar aponeuroses and tendons, but not of contracture bands. In normal tendons, normal palmar aponeuroses and apparently normal palmar aponeuroses residual strain and hysteresis loop increased significantly as a linear function of the amount of digested elastin. In contrast these biomechanical parameters were not affected significantly in contracture bands. In normal and apparently normal areas incubation with chondroitinase ABC resulted in a significant increase of residual strain and, as opposed to elastase, a decrease of normalized hysteresis loop. In contracture bands, however, these biomechanical parameters remained unchanged. RELEVANCE: The increasing evidence of a correlation between morphological changes of palmar elastin and ground substance with the progress of Dupuytren's disease emphasizes the need to determine the relative importance of these connective tissue components for the pathogenesis of Dupuytren's disease.

  12. A possible link between loading, inflammation and healing: Immune cell populations during tendon healing in the rat

    PubMed Central

    Blomgran, Parmis; Blomgran, Robert; Ernerudh, Jan; Aspenberg, Per

    2016-01-01

    Loading influences tendon healing, and so does inflammation. We hypothesized that the two are connected. 48 rats underwent Achilles tendon transection. Half of the rats received Botox injections into calf muscles to reduce mechanical loading. Cells from the regenerating tissue were analyzed by flow cytometry. In the loaded group, the regenerating tissue contained 83% leukocytes (CD45+) day 1, and 23% day 10. The M1/M2 macrophage ratio (CCR7/CD206) peaked at day 3, while T helper (CD3+CD4+) and Treg cells (CD25+ Foxp3+) increased over time. With Botox, markers associated with down-regulation of inflammation were more common day 5 (CD163, CD206, CD25, Foxp3), and M1 or M2 macrophages and Treg cells were virtually absent day 10, while still present with full loading. The primary variable, CCR7/CD206 ratio day 5, was higher with full loading (p = 0.001) and the Treg cell fraction was lower (p < 0.001). Free cage activity loading is known to increase size and strength of the tendon in this model compared to Botox. Loading now appeared to delay the switch to an M2 type of inflammation with more Treg cells. It seems a prolonged M1 phase due to loading might make the tendon regenerate bigger. PMID:27405922

  13. Pharmacological Regulation of In Situ Tissue Stem Cells Differentiation for Soft Tissue Calcification Treatment.

    PubMed

    Hu, Jia-Jie; Yin, Zi; Shen, Wei-Liang; Xie, Yu-Bin; Zhu, Ting; Lu, Ping; Cai, You-Zhi; Kong, Min-Jian; Heng, Boon Chin; Zhou, Yi-Ting; Chen, Wei-Shan; Chen, Xiao; Ouyang, Hong-Wei

    2016-04-01

    Calcification of soft tissues, such as heart valves and tendons, is a common clinical problem with limited therapeutics. Tissue specific stem/progenitor cells proliferate to repopulate injured tissues. But some of them become divergent to the direction of ossification in the local pathological microenvironment, thereby representing a cellular target for pharmacological approach. We observed that HIF-2alpha (encoded by EPAS1 inclined form) signaling is markedly activated within stem/progenitor cells recruited at calcified sites of diseased human tendons and heart valves. Proinflammatory microenvironment, rather than hypoxia, is correlated with HIF-2alpha activation and promoted osteochondrogenic differentiation of tendon stem/progenitor cells (TSPCs). Abnormal upregulation of HIF-2alpha served as a key switch to direct TSPCs differentiation into osteochondral-lineage rather than teno-lineage. Notably, Scleraxis (Scx), an essential tendon specific transcription factor, was suppressed on constitutive activation of HIF-2alpha and mediated the effect of HIF-2alpha on TSPCs fate decision. Moreover, pharmacological inhibition of HIF-2alpha with digoxin, which is a widely utilized drug, can efficiently inhibit calcification and enhance tenogenesis in vitro and in the Achilles's tendinopathy model. Taken together, these findings reveal the significant role of the tissue stem/progenitor cells fate decision and suggest that pharmacological regulation of HIF-2alpha function is a promising approach for soft tissue calcification treatment.

  14. 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.

  15. Polarized Raman anisotropic response of collagen in tendon: towards 3D orientation mapping of collagen in tissues.

    PubMed

    Galvis, Leonardo; Dunlop, John W C; Duda, Georg; Fratzl, Peter; Masic, Admir

    2013-01-01

    In this study, polarized Raman spectroscopy (PRS) was used to characterize the anisotropic response of the amide I band of collagen as a basis for evaluating three-dimensional collagen fibril orientation in tissues. Firstly, the response was investigated theoretically by applying classical Raman theory to collagen-like peptide crystal structures. The theoretical methodology was then tested experimentally, by measuring amide I intensity anisotropy in rat tail as a function of the orientation of the incident laser polarization. For the theoretical study, several collagen-like triple-helical peptide crystal structures obtained from the Protein Data Bank were rotated "in plane" and "out of plane" to evaluate the role of molecular orientation on the intensity of the amide I band. Collagen-like peptides exhibit a sinusoidal anisotropic response when rotated "in plane" with respect to the polarized incident laser. Maximal intensity was obtained when the polarization of the incident light is perpendicular to the molecule and minimal when parallel. In the case of "out of plane" rotation of the molecular structure a decreased anisotropic response was observed, becoming completely isotropic when the structure was perpendicular to the plane of observation. The theoretical Raman response of collagen was compared to that of alpha helical protein fragments. In contrast to collagen, alpha helices have a maximal signal when incident light is parallel to the molecule and minimal when perpendicular. For out-of-plane molecular orientations alpha-helix structures display a decreased average intensity. Results obtained from experiments on rat tail tendon are in excellent agreement with the theoretical predictions, thus demonstrating the high potential of PRS for experimental evaluation of the three-dimensional orientation of collagen fibers in biological tissues.

  16. Use of a Central Splitting Approach and Near Complete Detachment for Insertional Calcific Achilles Tendinopathy Repaired With an Achilles Bridging Suture.

    PubMed

    Gillis, Craig T; Lin, Jason S

    2016-01-01

    After 3 to 6 months of conservative management for insertional calcific Achilles tendinopathy, operative intervention might be warranted. Despite a success rate of 75% to 100% with surgery, no consensus has been reached on the amount of acceptable detachment of the Achilles tendon. The present case series reports on the results of a central splitting approach with 80% to 90% detachment of the Achilles insertion repaired with a double-row bridging suture device. A total of 14 patients (16 heels) for whom nonoperative management for insertional calcific Achilles tendinopathy had previously failed were enrolled in the present study they had undergone surgical management. The patients were followed up for a mean of 18 (range 11 to 25) months postoperatively and were evaluated using the American Orthopaedic Foot and Ankle Society Hind Foot scoring system, 36-item Short Form Health Survey questionnaire, and pre- and postoperative visual analog pain scale. The mean visual analog pain scale core had decreased 5.84 (range 1 to 9) points postoperatively (p < .001). The mean postoperative American Orthopaedic Foot and Ankle Society Hind Foot score was 87 ± 19.7 (range 52 to 105) points. One patient reported moderate pain with no limitation of activities. The mean 36-item Short-Form Health Survey score for physical functioning was 77.7 (range 30 to 100) points postoperatively in 11 patients. No patient reported incisional discomfort. All 14 patients (16 heels) reported being satisfied and had returned to their previous functional status. Thus, the central splitting Achilles approach with anchoring of the Achilles insertion using the double-row suture device is a safe and reasonable option in the operative treatment of insertional calcific Achilles tendinopathy.

  17. The use of nanotechnology in tendon regeneration and repair.

    PubMed

    Oragui, Emeka; Sachinis, Nick; Hope, Natalie; Khan, Wasim S; Adesida, Adetola

    2012-01-01

    Tendon injuries are common and due to their limited capacity for self-healing, the biomechanical and functional properties of healed tendon are usually inferior to normal tissue. Tissue engineering offers the hope of regenerating tendon tissue with the same biomechanical properties of the native undamaged tissue by augmenting the regenerative process of in vivo tissue or producing a functional tissue in vitro that can be implanted into the defective tendon site. Current research on tendon tissue engineering has focused on the role of stem cell and tendon derived cell therapy, scaffolds, chemical and physical stimulation and gene-therapeutic approaches. In this review we review the important functional anatomy and pathomechanics of tendon injury and discuss the current advances in tendon tissue engineering.

  18. Decellularized and Engineered Tendons as Biological Substitutes: A Critical Review

    PubMed Central

    Lovati, Arianna B.; Bottagisio, Marta; Moretti, Matteo

    2016-01-01

    Tendon ruptures are a great burden in clinics. Finding a proper graft material as a substitute for tendon repair is one of the main challenges in orthopaedics, for which the requirement of a biological scaffold would be different for each clinical application. Among biological scaffolds, the use of decellularized tendon-derived matrix increasingly represents an interesting approach to treat tendon ruptures. We analyzed in vitro and in vivo studies focused on the development of efficient protocols for the decellularization and for the cell reseeding of the tendon matrix to obtain medical devices for tendon substitution. Our review considered also the proper tendon source and preclinical animal models with the aim of entering into clinical trials. The results highlight a wide panorama in terms of allogenic or xenogeneic tendon sources, specimen dimensions, physical or chemical decellularization techniques, and the cell type variety for reseeding from terminally differentiated to undifferentiated mesenchymal stem cells and their static or dynamic culture employed to generate implantable constructs tested in different animal models. We try to identify the most efficient approach to achieve an optimal biological scaffold for biomechanics and intrinsic properties, resembling the native tendon and being applicable in clinics in the near future, with particular attention to the Achilles tendon substitution. PMID:26880985

  19. Achilles tendinosis: a morphometrical study in a rat model.

    PubMed

    Silva, Rafael Duarte; Glazebrook, Mark Anthony; Campos, Vinicius Castro; Vasconcelos, Anilton Cesar

    2011-01-01

    This study addresses the morphopathogenesis of Achilles tendinosis, using a rat model and presenting quantitative analysis of time-dependent histological changes. Thirty Wistar rats were used, randomly split in experimental and control groups. Animals of the experimental group were submitted to a treadmill running scheme. Five animals of each group were euthanized at four, eight and sixteen weeks. Achilles tendons were collected and processed routinely for histopath sections. Slides were stained by Hematoxylin-Eosin, Picrosirius Red, Alcian Blue, AgNOR, TUNEL and evaluated morphometrically. Cellular density decreased slightly along the time and was higher in the experimental group than in controls at fourth, eighth and sixteenth weeks. Fiber microtearing, percentual of reticular fibers and glycosaminoglycans content increased along the time and were higher in experimental group than in controls at all-time intervals. AgNOR labeling here interpreted as a marker of transcription activity was higher in the experimental groups than in controls at all-time intervals. Apoptotic cells were more frequent and diffusely distributed in tendinosis samples than in control groups. These results suggest that as mechanical overload is becoming chronic, cellular turnover and matrix deposition increases leading to tendinosis. The combination of staining techniques and morphometry used here to describe the evolution of lesions occurring in a rat model system has proved to be suited for the study of induced Achilles tendinosis.

  20. Effect of joint rotation correction when measuring elongation of the gastrocnemius medialis tendon and aponeurosis.

    PubMed

    Arampatzis, Adamantios; Monte, Gianpiero De; Karamanidis, Kiros

    2008-06-01

    It is well known that during maximal plantar flexion contractions the ankle joint rotation overestimates the actual elongation of the tendon and aponeurosis. The aim of this study was to examine the influence of the curve length changes of the Achilles tendon on the joint rotation corrected elongation and strain of the gastrocnemius medialis (GM) tendon and aponeurosis. Nine subjects (age: 29.4+/-5.7 years, body mass: 78.8+/-6.8 kg, body height: 178+/-4 cm) participated in the study. The subjects performed maximal voluntary isometric plantarflexion contractions in the prone position on a Biodex-dynamometer. Ultrasonography (Aloka SSD 4000) was used to visualize the muscle belly of the GM muscle-tendon unit. To calculate the curve length changes of the Achilles tendon its surface contour was reconstructed using a series of small reflective skin markers having a diameter of 2.5mm. The elongation of the GM tendon and aponeurosis was calculated (a) as the difference of the measured and the passive (due to joint rotation) displacement of the tendon and aponeurosis and (b) as the difference of the measured displacement and the length changes of the reconstructed Achilles tendon surface contour. The absolute difference between the elongation obtained by both methods were 1.2+/-0.4mm. These differences were due to the higher changes in length obtained by the reconstruction of the tendon curved surface contour as compared to the changes observed in the passive displacement of the digitised point at the aponeurosis. Without correcting for angle joint rotation, the measured elongation clearly overestimates the actual elongation of the GM tendon and aponeurosis. After the passive displacement correction the calculated elongation still overestimates the actual elongation of the GM tendon and aponeurosis. However, this overestimation has a negligible effect on the examined in vivo strain ( approximately 0.3%) of the tendon and aponeurosis.

  1. Relationship between neovascularization and clinical severity in Achilles tendinopathy in 556 paired measurements.

    PubMed

    De Jonge, S; Warnaars, J L F; De Vos, R J; Weir, A; van Schie, H T M; Bierma-Zeinstra, S M A; Verhaar, J A N; Tol, J L

    2014-10-01

    Neovascularization is frequently observed in tendinopathy. Previous studies have focused on the role of neovascularization in Achilles tendinopathy, but have been conducted in small series. It is still unclear whether the degree of neovascularization is related to severity of symptoms. The purpose was to study the relationship between ultrasonographic neovascularization and clinical severity in patients with Achilles tendinopathy. In this prospective cohort study, data on 127 patients (141 tendons) were assembled from databases of three clinical trials. All patients followed an eccentric exercise program. The Öhberg neovascularization score (0-4+) and Victorian Institute of Sports Assessment-Achilles (VISA-A) score (split into domains: pain, function and activity) were collected during baseline and follow-up. The relationship between neovascularization and VISA-A score was calculated. At baseline, 107 tendons (76%) showed some degree of neovascularization. In 556 coupled measurements, neovascularization was weakly related to the VISA-A score [Exp (B) 1.017, 95% confidence interval (CI), 1.007-1.026]. No significant relationship was found between neovascularization and the pain domain (P = 0.277) and the activity domain (P = 0.283), but there was between neovascularization and the function domain of the VISA-A score [Exp (B) = 1.067, 95% CI 1.018-1.119]. In conclusion, neovascularization in Achilles tendinopathy is weakly related to clinical severity, mainly based on the function domain of the VISA-A score.

  2. Achilles Tendinopathy: Current Concepts about the Basic Science and Clinical Treatments.

    PubMed

    Li, Hong-Yun; Hua, Ying-Hui

    2016-01-01

    Achilles tendinopathy is one of the most frequently ankle and foot overuse injuries, which is a clinical syndrome characterized by the combination of pain, swelling, and impaired performance. The two main categories of Achilles tendinopathy are classified according to anatomical location and broadly include insertional and noninsertional tendinopathy. The etiology of Achilles tendinopathy is multifactorial including both intrinsic and extrinsic factors. Failed healing response and degenerative changes were found in the tendon. The failed healing response includes three different and continuous stages (reactive tendinopathy, tendon disrepair, and degenerative tendinopathy). The histological studies have demonstrated an increased number of tenocytes and concentration of glycosaminoglycans in the ground substance, disorganization and fragmentation of the collagen, and neovascularization. There are variable conservative and surgical treatment options for Achilles tendinopathy. However, there has not been a gold standard of these treatments because of the controversial clinical results between various studies. In the future, new level I researches will be needed to prove the effect of these treatment options.

  3. Achilles Tendinopathy: Current Concepts about the Basic Science and Clinical Treatments

    PubMed Central

    Li, Hong-Yun

    2016-01-01

    Achilles tendinopathy is one of the most frequently ankle and foot overuse injuries, which is a clinical syndrome characterized by the combination of pain, swelling, and impaired performance. The two main categories of Achilles tendinopathy are classified according to anatomical location and broadly include insertional and noninsertional tendinopathy. The etiology of Achilles tendinopathy is multifactorial including both intrinsic and extrinsic factors. Failed healing response and degenerative changes were found in the tendon. The failed healing response includes three different and continuous stages (reactive tendinopathy, tendon disrepair, and degenerative tendinopathy). The histological studies have demonstrated an increased number of tenocytes and concentration of glycosaminoglycans in the ground substance, disorganization and fragmentation of the collagen, and neovascularization. There are variable conservative and surgical treatment options for Achilles tendinopathy. However, there has not been a gold standard of these treatments because of the controversial clinical results between various studies. In the future, new level I researches will be needed to prove the effect of these treatment options. PMID:27885357

  4. 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

  5. Prevalence of Achilles and patellar tendinopathy and their association to intratendinous changes in adolescent athletes.

    PubMed

    Cassel, M; Baur, H; Hirschmüller, A; Carlsohn, A; Fröhlich, K; Mayer, F

    2015-06-01

    Achilles (AT) and patellar tendons (PT) are commonly affected by tendinopathy in adult athletes but prevalence of symptoms and morphological changes in adolescents is unclear. The study aimed to determine prevalence of tendinopathy and intratendinous changes in ATs and PTs of adolescent athletes. A total of 760 adolescent athletes (13.0 ± 1.9 years; 160 ± 13 cm; 50 ± 14 kg) were examined. History, local clinical examination, and longitudinal Doppler ultrasound analysis for both ATs and PTs were performed including identification of intratendinous echoic changes and vascularization. Diagnosis of tendinopathy was complied clinically in case of positive history of tendon pain and tendon pain on palpation. Achilles tendinopathy was diagnosed in 1.8% and patellar tendinopathy in 5.8%. Vascularizations were visible in 3.0% of ATs and 11.4% of PTs, hypoechogenicities in 0.7% and 3.2% as well as hyperechogenicities in 0% and 0.3%, respectively. Vascularizations and hypoechogenicities were statistically significantly more often in males than in females (P ≤ 0.02). Subjects with patellar tendinopathy had higher prevalence of structural intratendinous changes than those without PT symptoms (P ≤ 0.001). In adolescent athletes, patellar tendinopathy is three times more frequent compared with Achilles tendinopathy. Longitudinal studies are necessary to investigate physiological or pathological origin of vascularizations and its predictive value in development of tendinopathy.

  6. The Tendon-to-Bone Transition of the Rotator Cuff: A Preliminary Raman Spectroscopic Study Documenting the Gradual Mineralization Across the Insertion in Rat Tissue Samples

    PubMed Central

    WOPENKA, BRIGITTE; KENT, ALISTAIR; PASTERIS, JILL D.; YOON, YOUNG; THOMOPOULOS, STAVROS

    2009-01-01

    We applied Raman spectroscopy to monitor the distribution of minerals and the degree of mineralization across the tendon–bone insertion site in the shoulders of five rats. We acquired Raman spectra from 100 to 4000 Δcm-1 on individual 1 μm points across the 120 μm wide transition zone of each tissue sample and identified all the peaks detected in pure tendon and in pure bone, as well as in the transition zone. The intensity of the 960 Δcm-1 P–O stretch for apatite (normalized to either the 2940 Δcm-1 C–H stretch or the 1003 Δcm-1 C–C stretch for collagen) was used as an indicator of the abundance of mineral. We relate the observed histological morphology in the tissue thin section with the observed Raman peaks for both the organic component (mostly collagen) and the inorganic component (a carbonated form of the mineral apatite) and discuss spectroscopic issues related to peak deconvolution and quantification of overlapping Raman peaks. We show that the mineral-to-collagen ratio at the insertion site increases linearly (R2 = 0.8 for five samples) over the distance of 120 μm from tendon to bone, rather than abruptly, as previously inferred from histological observations. In addition, narrowing of the 960 Δcm-1 band across the traverse indicates that the crystalline ordering within the apatite increases concomitantly with the degree of mineralization. This finding of mineral gradation has important clinical implications and may explain why the uninjured tendon-to-bone connection of the rotator cuff can sustain very high stress concentrations without failure. Our finding is also consistent with recent mechanical models and calculations developed to better understand the materials properties of this unusually strong interface. PMID:19094386

  7. Birefringence and second harmonic generation on tendon collagen following red linearly polarized laser irradiation.

    PubMed

    Silva, Daniela Fátima Teixeira; Gomes, Anderson Stevens Leonidas; de Campos Vidal, Benedicto; Ribeiro, Martha Simões

    2013-04-01

    Regarding the importance of type I collagen in understanding the mechanical properties of a range of tissues, there is still a gap in our knowledge of how proteins perform such work. There is consensus in literature that the mechanical characteristics of a tissue are primarily determined by the organization of its molecules. The purpose of this study was to characterize the organization of non-irradiated and irradiated type I collagen. Irradiation was performed with a linearly polarized HeNe laser (λ = 632.8 nm) and characterization was undertaken using polarized light microscopy to investigate the birefringence and second harmonic generation to analyze nonlinear susceptibility. Rats received laser irradiation (P = 6.0 mW, I = 21.2 mW/cm(2), E ≈ 0.3 J, ED = 1.0 J/cm(2)) on their healthy Achilles tendons, which after were extracted to prepare the specimens. Our results show that irradiated samples present higher birefringence and greater non-linear susceptibility than non-irradiated samples. Under studied conditions, we propose that a red laser with polarization direction aligned in parallel to the tendon long axis promotes further alignment on the ordered healthy collagen fibrils towards the electric field incident. Thus, prospects for biomedical applications for laser polarized radiation on type I collagen are encouraging since it supports greater tissue organization.

  8. Ultrasound-guided retro-calcaneal bursa corticosteroid injection for refractory Achilles tendinitis in patients with seronegative spondyloarthropathy: efficacy and follow-up study.

    PubMed

    Srivastava, Puja; Aggarwal, Amita

    2016-06-01

    Ultrasound (US)-guided corticosteroid injection has been shown to be safe and effective for varied causes of plantar fasciitis; however, its use for Achilles tendinitis is controversial. We studied the efficacy and changes in US findings at Achilles enthesitis after corticosteroid injection in patients with spondyloarthropathy (SpA). Patients with SpA with symptomatic Achilles enthesitis, refractory to 6 weeks of full-dose NSAIDs, were offered US-guided local corticosteroid injection. Injected entheses were examined by US (both B mode and power Doppler) at baseline and 6 weeks after injection. Standard OMERACT definitions were used to define enthesitis. Achilles tendon thickness >5.29 mm, 2 cm proximal to insertion in long axis, was considered thickened. Twenty-seven symptomatic Achilles tendons (in 18 patients) were injected with 20 mg methylprednisolone under US guidance baseline, and 6-week follow-up US features were compared. All patients reported improvement in pain (VAS) in the affected tendon after injection (p < 0.0001). Simultaneously, improvement in local inflammatory changes were noted, in the form of significant reduction in tendon thickness (p < 0.0001), vascularity (p < 0.0001), peritendinous oedema (p = 0.001), bursitis and bursal vascularity (p < 0.001 and < 0.0001, respectively). There was no change in bone erosions and enthesophyte. None of the patients had tendon rupture or other injection-related complications at 6 weeks of follow-up. US-guided local corticosteroid injection is an effective and safe modality for refractory Achilles enthesitis in patients with SpA and leads to reversion of acute changes at entheseal site.

  9. The role of microvesicles derived from mesenchymal stem cells in tissue regeneration; a dream for tendon repair?

    PubMed Central

    Tetta, Ciro; Consiglio, Anna Lange; Bruno, Stefania; Tetta, Emanuele; Gatti, Emanuele; Dobreva, Miryana; Cremonesi, Fausto; Camussi, Giovanni

    2012-01-01

    Summary Tendon injuries represent even today a challenge as repair may be exceedingly slow and incomplete. Regenerative medicine and stem cell technology have shown to be of great promise. Here, we will review the current knowledge on the mechanisms of the regenerative potential of mesenchymal stem cells (MSCs) obtained from different sources (bone marrow, fat, cord blood, placenta). More specifically, we will devote attention to the current use of MSCs that have been used experimentally and in limited numbers of clinical cases for the surgical treatment of subchondral-bone cysts, bone-fracture repair and cartilage repair. Based on the recently emerging role in regenerative mechanisms of soluble factors and of extracellular vesicles, we will discuss the potential of non-cellular therapies in horse tendon injuries. PMID:23738299

  10. Mesenchymal stem cell applications to tendon healing

    PubMed Central

    Chaudhury, Salma

    2012-01-01

    Summary Tendons are often subject to age related degenerative changes that coincide with a diminished regenerative capacity. Torn tendons often heal by forming scar tissue that is structurally weaker than healthy native tendon tissue, predisposing to mechanical failure. There is increasing interest in providing biological stimuli to increase the tendon reparative response. Stem cells in particular are an exciting and promising prospect as they have the potential to provide appropriate cellular signals to encourage neotendon formation during repair rather than scar tissue. Currently, a number of issues need to be investigated further before it can be determined whether stem cells are an effective and safe therapeutic option for encouraging tendon repair. This review explores the in-vitro and invivo evidence assessing the effect of stem cells on tendon healing, as well as the potential clinical applications. PMID:23738300

  11. Tendon Vasculature in Health and Disease

    PubMed Central

    Tempfer, Herbert; Traweger, Andreas

    2015-01-01

    Tendons represent a bradytrophic tissue which is poorly vascularized and, compared to bone or skin, heal poorly. Usually, a vascularized connective scar tissue with inferior functional properties forms at the injury site. Whether the increased vascularization is the root cause of tissue impairments such as loss of collagen fiber orientation, ectopic formation of bone, fat or cartilage, or is a consequence of these pathological changes remains unclear. This review provides an overview of the role of tendon vasculature in healthy and chronically diseased tendon tissue as well as its relevance for tendon repair. Further, the nature and the role of perivascular tendon stem/progenitor cells residing in the vascular niche will be discussed and compared to multipotent stromal cells in other tissues. PMID:26635616

  12. 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.

  13. Proton microprobe analysis of zinc in skeletal tissues. [Proton induced x-ray emission analysis

    SciTech Connect

    Doty, S B; Jones, K W; Kraner, H W; Shroy, R E; Hanson, A L

    1980-06-01

    A proton microprobe with windowless exit port was used to study zinc distributions in various types of skeletal tissues. The use of an external beam facilitated positioning of the targets for examination of particular points of interest. The proton microprobe is uniquely suited to this work since it combines high sensitivity for zinc determinations in thick samples with good spatial resolution. Measurements on rat and rabbit Achilles tendon showed a significant increase in zinc concentrations as the beam moved from the unmineralized collagen into the mineralized attachment site. Cartilage gave a similar result, with calcified cartilage having a greater zinc level than the articular surface on unmineralized epiphyseal cartilage.

  14. Nano/micro hybrid scaffold of PCL or P3HB nanofibers combined with silk fibroin for tendon and ligament tissue engineering.

    PubMed

    Naghashzargar, Elham; Farè, Silvia; Catto, Valentina; Bertoldi, Serena; Semnani, Dariush; Karbasi, Saeed; Tanzi, Maria Cristina

    2015-07-04

    A novel biodegradable nano/micro hybrid structure was obtained by electrospinning P3HB or PCL nanofibers onto a twisted silk fibroin (SF) structure, with the aim of fabricating a suitable scaffold for tendon and ligament tissue engineering. The electrospinning (ES) processing parameters for P3HB and PCL were optimized on 2D samples, and applied to produce two different nano/micro hybrid constructs (SF/ES-PCL and SF/ES-P3HB).Morphological, chemico-physical and mechanical properties of the novel hybrid scaffolds were evaluated by SEM, ATR FT-IR, DSC, tensile and thermodynamic mechanical tests. The results demonstrated that the nanofibers were tightly wrapped around the silk filaments, and the crystallinity of the SF twisted yarns was not influenced by the presence of the electrospun polymers. The slightly higher mechanical properties of the hybrid constructs confirmed an increase of internal forces due to the interaction between nano and micro components. Cell culture tests with L929 fibroblasts, in the presence of the sample eluates or in direct contact with the hybrid structures, showed no cytotoxic effects and a good level of cytocompatibility of the nano/micro hybrid structures in term of cell viability, particularly at day 1. Cell viability onto the nano/micro hybrid structures decreased from the first to the third day of culture when compared with the control culture plastic, but appeared to be higher when compared with the uncoated SF yarns. Although additional in vitro and in vivo tests are needed, the original fabrication method here described appears promising for scaffolds suitable for tendon and ligament tissue engineering.

  15. Association of Achilles tendinopathy and plantar spurs.

    PubMed

    Vulcano, Ettore; Mani, Sriniwasan B; Mani, Sriniwasan; Do, Huong; Bohne, Walter H; Ellis, Scott J

    2014-10-01

    Plantar spurs and Achilles tendinopathy are common causes of heel pain. In the authors' practice, it was anecdotally noted that patients with Achilles tendinopathy often presented with plantar spurs. Nonetheless, there is a shortage of studies investigating whether Achilles tendinopathy and plantar spurs exist concomitantly. A better understanding of the association between the 2 pathologies might help physicians recognize and treat both conditions, educate patients about Achilles tendinopathy and plantar spurs, and ultimately investigate possible underlying causes of both pathologies that could be addressed together. The authors examined the prevalence of plantar spurs in patients diagnosed with Achilles tendinopathy as well as demographic differences within the unilateral and bilateral Achilles tendinopathy populations. A total of 785 patient records were retrospectively reviewed. Mean patient age was 56.2±15.5 years (46.9% men and 53.1% women). Seventy-two (9.2%) patients were affected bilaterally by Achilles tendinopathy. Lateral radiographs were reviewed by an orthopedic surgeon to identify the presence of plantar spurs. A total of 329 (41.9%) patients with Achilles tendinopathy were found to have a concomitant plantar spur. Patients with unilateral Achilles tendinopathy and a plantar spur were more likely to be women (58.7% vs 49.8%, P=.020) and older (62.7 vs 51.7 years, P<.001). In the bilateral Achilles tendinopathy group, there were 46 (63.9%) patients with at least one foot presenting with a plantar spur. The study's findings suggest a significant association between Achilles tendinopathy and plantar spurs. Older women with Achilles tendinopathy are at greater risk of being affected by plantar spurs.

  16. A Proposed Return-to-Sport Program for Patients With Midportion Achilles Tendinopathy: Rationale and Implementation.

    PubMed

    Silbernagel, Karin Grävare; Crossley, Kay M

    2015-11-01

    Synopsis Achilles tendinopathy is a common overuse injury in athletes involved in running and jumping activities and sports. The intervention with the highest level of evidence is exercise therapy, and it is recommended that all patients initially be treated with exercise for at least 3 months prior to considering other treatment options. Recovery from Achilles tendinopathy can take up to a year, and there is a high propensity for recurrence, especially during the return-to-sport phase. The extent of the tendon injury, the age and sex of the athlete, the magnitude of pain/symptoms, the extent of impairments, and the demands of the sport all need to be considered when planning for return to sport. This clinical commentary describes an approach to return to sport for patients with midportion Achilles tendinopathy. The aim of the return-to-sport program is to facilitate the decision-making process in returning an athlete with midportion Achilles tendinopathy back to full sport participation and to minimize the chances for recurrence of the injury. J Orthop Sports Phys Ther 2015;45(11):876-886. Epub 21 Sep 2015. doi:10.2519/jospt.2015.5885.

  17. 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

  18. Spontaneous Iliopsoas Tendon Tear

    PubMed Central

    Rodriguez, Mary; Patnaik, Soumya; Wang, Peter

    2016-01-01

    Hip pain is one of the most common reasons for the elderly to present to the emergency department, and the differential diagnosis spectrum is vast. Iliopsoas injury is a relatively uncommon condition that may present with hip or groin pain. It is usually seen in athletes due to trauma, particularly flexion injuries. However, spontaneous iliopsoas tendon tear is extremely rare, and only a small number of cases have been reported; it has an estimated prevalence of 0.66% in individuals from 7 to 95 years. Risk factors include aging, use of steroids, and chronic diseases. Magnetic resonance imaging (MRI) using its high soft-tissue contrast resolution remains the most valuable imaging modality. A prompt diagnosis and treatment, which is usually conservative, is important to improve the quality of life in this group of patients. We describe a case of spontaneous iliopsoas tendon tear in an elderly woman. PMID:26929854

  19. Hyaluronic acid and tendon lesions

    PubMed Central

    Kaux, Jean-François; Samson, Antoine; Crielaard, Jean-Michel

    2015-01-01

    Summary Introduction recently, the viscoelastic properties of hyaluronic acid (HA) on liquid connective tissue have been proposed for the treatment of tendinopathies. Some fundamental studies show encouraging results on hyaluronic acid’s ability to promote tendon gliding and reduce adhesion as well as to improve tendon architectural organisation. Some observations also support its use in a clinical setting to improve pain and function. This literature review analyses studies relating to the use of hyaluronic acid in the treatment of tendinopathies. Methods this review was constructed using the Medline database via Pubmed, Scopus and Google Scholar. The key words hyaluronic acid, tendon and tendinopathy were used for the research. Results in total, 28 articles (in English and French) on the application of hyaluronic acid to tendons were selected for their relevance and scientific quality, including 13 for the in vitro part, 7 for the in vivo animal part and 8 for the human section. Conclusions preclinical studies demonstrate encouraging results: HA permits tendon gliding, reduces adhesions, creates better tendon architectural organisation and limits inflammation. These laboratory observations appear to be supported by limited but encouraging short-term clinical results on pain and function. However, controlled randomised studies are still needed. PMID:26958533

  20. Microstructural stress relaxation mechanics in functionally different tendons.

    PubMed

    Screen, H R C; Toorani, S; Shelton, J C

    2013-01-01

    Tendons experience widely varying loading conditions in vivo. They may be categorised by their function as either positional tendons, which are used for intricate movements and experience lower stress, or as energy storage tendons which act as highly stressed springs during locomotion. Structural and compositional differences between tendons are thought to enable an optimisation of their properties to suit their functional environment. However, little is known about structure-function relationships in tendon. This study adopts porcine flexor and extensor tendon fascicles as examples of high stress and low stress tendons, comparing their mechanical behaviour at the micro-level in order to understand their stress relaxation response. Stress-relaxation was shown to occur predominantly through sliding between collagen fibres. However, in the more highly stressed flexor tendon fascicles, more fibre reorganisation was evident when the tissue was exposed to low strains. By contrast, the low load extensor tendon fascicles appears to have less capacity for fibre reorganisation or shearing than the energy storage tendon, relying more heavily on fibril level relaxation. The extensor fascicles were also unable to sustain loads without rapid and complete stress relaxation. These findings highlight the need to optimise tendon repair solutions for specific tendons, and match tendon properties when using grafts in tendon repairs.

  1. Management of Extensor Tendon Injuries

    PubMed Central

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

    2012-01-01

    Extensor tendon injuries are very common injuries, which inappropriately treated can cause severe lasting impairment for the patient. Assessment and management of flexor tendon injuries has been widely reviewed, unlike extensor injuries. It is clear from the literature that extensor tendon repair should be undertaken immediately but the exact approach depends on the extensor zone. Zone I injuries otherwise known as mallet injuries are often closed and treated with immobilisaton and conservative management where possible. Zone II injuries are again conservatively managed with splinting. Closed Zone III or ‘boutonniere’ injuries are managed conservatively unless there is evidence of displaced avulsion fractures at the base of the middle phalanx, axial and lateral instability of the PIPJ associated with loss of active or passive extension of the joint or failed non-operative treatment. Open zone III injuries are often treated surgically unless splinting enable the tendons to come together. Zone V injuries, are human bites until proven otherwise requires primary tendon repair after irrigation. Zone VI injuries are close to the thin paratendon and thin subcutaneous tissue which strong core type sutures and then splinting should be placed in extension for 4-6 weeks. Complete lacerations to zone IV and VII involve surgical primary repair followed by 6 weeks of splinting in extension. Zone VIII require multiple figure of eight sutures to repair the muscle bellies and static immobilisation of the wrist in 45 degrees of extension. To date there is little literature documenting the quality of repairing extensor tendon injuries however loss of flexion due to extensor tendon shortening, loss of flexion and extension resulting from adhesions and weakened grip can occur after surgery. This review aims to provide a systematic examination method for assessing extensor injuries, presentation and management of all type of extensor tendon injuries as well as guidance on

  2. Solvent-free fabrication of three dimensionally aligned polycaprolactone microfibers for engineering of anisotropic tissues.

    PubMed

    An, Jia; Chua, Chee Kai; Leong, Kah Fai; Chen, Chih-Hao; Chen, Jyh-Ping

    2012-10-01

    Fabrication of aligned microfiber scaffolds is critical in successful engineering of anisotropic tissues such as tendon, ligaments and nerves. Conventionally, aligned microfiber scaffolds are two dimensional and predominantly fabricated by electrospinning which is solvent dependent. In this paper, we report a novel technique, named microfiber melt drawing, to fabricate a bundle of three dimensionally aligned polycaprolactone microfibers without using any organic solvent. This technique is simple yet effective. It has been demonstrated that polycaprolactone microfibers of 10 μm fiber diameter can be directly drawn from a 2 mm orifice. Orifice diameter, temperature and take-up speed significantly influence the final linear density and fiber diameter of the microfibers. Mechanical test suggests that mechanical properties such as stiffness and breaking force of microfiber bundles can be easily adjusted by the number of fibers. In vitro study shows that these microfibers are able to support the proliferation of human dermal fibroblasts over 7 days. In vivo result of Achilles tendon repair in a rabbit model shows that the microfibers were highly infiltrated by tendon tissue as early as in 1 month, besides, the repaired tendon have a well-aligned tissue structure under the guidance of aligned microfibers. However whether these three dimensionally aligned microfibers can induce three dimensionally aligned cells remains inconclusive.

  3. Influence of structure on the tissue dynamics of the human soleus muscle observed in MRI studies during isometric contractions.

    PubMed

    Hodgson, John A; Finni, Taija; Lai, Alex M; Edgerton, V Reggie; Sinha, Shantanu

    2006-05-01

    This article investigates how the internal structure of muscle and its relationship with tendon and even skeletal structures influence the translation of muscle fiber contractions into movement of a limb. Reconstructions of the anatomy of the human soleus muscle from the Visible Human Dataset (available from the National Library of Medicine), magnetic resonance images (MRI), and cadaver studies revealed a complex 3D connective tissue structure populated with pennate muscle fibers. The posterior aponeurosis and the median septum of the soleus form the insertion of the muscle and are continuous with the Achilles tendon. The distal extremities of the pennate muscle fibers attach to these structures. The anterior aponeurosis is located intramuscularly, between the posterior aponeurosis and the median septum. It forms the origin of the muscle and contacts the proximal extremities of the soleus muscle fibers. MRI measurements of in vivo tissue velocities during isometric contractions (20% and 40% maximum voluntary contractions) revealed a similarly complex 3D distribution of tissue movements. The distribution of velocities was similar to the distribution of major connective tissue structures within the muscle. During an isometric contraction, muscle fiber contractions move the median septum and posterior aponeurosis proximally, relative to the anterior aponeurosis. The pennate arrangement of muscle fibers probably amplifies muscle fiber length changes but not sufficiently to account for the twofold difference in muscle fiber length changes relative to excursion of the calcaneus. The discrepancy may be accounted for by an additional gain mechanism operating directly on the Achilles tendon by constraining the posterior movement of the tendon, which would otherwise occur due to the increasingly posterior location of the calcaneus in plantarflexeion.

  4. 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.

  5. The effect of tendon surface treatment on cell attachment for potential enhancement of tendon graft healing: an ex vivo model.

    PubMed

    Hashimoto, Takahiro; Sun, Yu-Long; An, Kai-Nan; Amadio, Peter C; Zhao, Chunfeng

    2012-12-01

    For both tendon allografts and autografts, the surface, initially optimized for gliding, may not be ideal to facilitate tissue integration for graft healing to host tendon or bone. As a prelude to studying tendon-bone integration, we investigated the effect of surface treatments with trypsin or mechanical abrasion on cell attachment to the tendon surface in a canine ex vivo intrasynovial tendon tissue culture model. Intrasynovial tendon allograft surfaces were seeded with cells after the following treatments: (1) no treatment, (2) mechanical abrasion, (3) trypsin, and (4) abrasion and trypsin. The area covered by cells was determined using confocal laser microscopy at one and two weeks. Results were compared to untreated extrasynovial tendon. Additional tendons were characterized with scanning electron microscopy. Tendons with trypsin treatment had significantly more surface coverage with cells than the other groups, after both one and two weeks of culture. In terms of the cellular shape and size, cells on tendons with trypsin treatment spread more and were more polygonal in shape, whereas tendons with mechanical abrasion with/without trypsin treatment contained smaller, more spindle-like cells. Surface roughening can affect cell behavior with topographical stimulation. Trypsin surface digestion exposes a mesh-like structure on the tendon surface, which could enhance cell adherence and, possibly, tendon/bone healing.

  6. Extra-corporeal pulsed-activated therapy ("EPAT" sound wave) for Achilles tendinopathy: a prospective study.

    PubMed

    Saxena, Amol; Ramdath, Sona; O'Halloran, Patrick; Gerdesmeyer, Ludger; Gollwitzer, Hans

    2011-01-01

    Achilles tendinopathy is common and extracorporeal shockwaves have become a popular treatment for this condition, even though previous research has not provided conclusive results regarding its efficacy in cases of Achilles tendinopathy. Our aim was to evaluate 3 weekly shockwave treatments in patients with Achilles tendinopathy, as quantified by the Roles and Maudsley score. A total of 74 tendons in 60 patients were assessed at baseline and at least 1 year posttreatment, including 32 (43.24%) paratendinoses, 23 (31.08%) proximal tendinoses, and 19 (25.68%) insertional tendinoses. The mean age of the participants was 48.6 ± 12.94 years, and patients with paratendinosis (41.44 ± 14.01 years) were statistically significantly younger than those with proximal (53 ± 8.9 years) and insertional (54.26 ± 9.74 years) tendinopathy, and these differences were statistically significant (P = .0012 and P = .0063, respectively). Overall, 58 (78.38%) tendons improved by at least 1 year posttreatment, including 75% in the paratendinosis, 78.26% in the proximal tendinosis, and 84.21% in the insertional tendinosis groups, and no adverse effects were observed. The Roles and Maudsley score improved from 3.22 ± 0.55 to 1.84 ± 1.05 (P < .0001) in the paratendinosis group, 3.39 ± 0.5 to 1.57 ± 0.66 (P < .0001) in the proximal tendinopathy group, and 3.32 ± 0.58 to 1.47 ± 0.7 (P = .0001) in the insertional tendinopathy group. Based on these results, we believe that shockwave therapy serves as a safe, viable, and effective option for the treatment of Achilles tendinopathy.

  7. Intermittent pneumatic compression enhances neurovascular ingrowth and tissue proliferation during connective tissue healing: a study in the rat.

    PubMed

    Dahl, Johan; Li, Jian; Bring, Daniel K-I; Renström, Per; Ackermann, Paul W

    2007-09-01

    Intermittent pneumatic compression (IPC) is a treatment method to decrease venous stasis and stimulate blood flow. Recently, it was hypothesized that IPC may exert positive effects on tissue healing, a process highly dependent upon adequate circulation. In this study, we investigated the effects of daily 1-h IPC treatment during 2 and 4 weeks post-rat Achilles tendon rupture. The tendons were subjectively and semiquantitatively analyzed for collagen organization, fibroblast density, angiogenesis, and the occurrence of sensory neuropeptides, substance P (SP) and calcitonine gene related peptide (CGRP), as well as for a nerve regeneration marker, growth associated protein 43 (GAP-43). After 2 weeks of treatment, fibroblast density increased by 53% (p = 0.0004), vessel density by 64% (p = 0.022), and the occurrence of SP by 110% (p = 0.047) and CGRP by 47% (p = 0.0163) compared to untreated controls. Following 4 weeks of treatment, both the occurrence of sensory neuropeptides and the vessel density remained significantly higher (p < 0.05), whereas fibroblast density returned to normal. However, at 4 weeks the treated tendons displayed a higher degree of organized parallel collagen fibers, a sign of increased maturation. Daily IPC treatment improves neurovascular ingrowth and fibroblast proliferation in the healing tendon and may accelerate the repair process.

  8. 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

  9. Constitutive modeling of crimped collagen fibrils in soft tissues.

    PubMed

    Grytz, Rafael; Meschke, Günther

    2009-10-01

    A microstructurally oriented constitutive formulation for the hyperelastic response of crimped collagen fibrils existing in soft connective tissues is proposed. The model is based on observations that collagen fibrils embedded in a soft matrix crimp into a smooth three-dimensional pattern when unloaded. Following ideas presented by Beskos and Jenkins [Beskos, D., Jenkins, J., 1975. A mechanical model for mammalian tendon. ASME Journal of Applied Mechanics 42, 755-758] and Freed and Doehring [Freed, A., Doehring, T., 2005. Elastic model for crimped collagen fibrils. Journal of Biomechanical Engineering 127, 587-593] the collagen fibril crimp is approximated by a cylindrical helix to represent the constitutive behavior of the hierarchical organized substructure of biological tissues at the fibrillar level. The model is derived from the nonlinear axial force-stretch relationship of an extensible helical spring, including the full extension of the spring as a limit case. The geometrically nonlinear solution of the extensible helical spring is carried out by an iterative procedure. The model only requires one material parameter and two geometrical parameters to be determined from experiments. The ability of the proposed model to reproduce the biomechanical response of fibrous tissues is demonstrated for fascicles from rat tail tendons, for porcine cornea strips, and for bovine Achilles tendons.

  10. Bilateral Patellar Tendon Rupture

    DTIC Science & Technology

    2009-07-01

    within the tendon or systemic disorders such as lupus erythematosus , diabetes mellitus, chronic kidney disease, rheumatologic disease, and local or...factors for patellar tendon rupture include obesity, male gender, age 30-40, activities that increase patellar stress, systemic lupus erythematosus ...patellar tendon rupture is a rare occurrence usually associated with chronic degeneration of tendon fibers, use of steroids, or systemic illness. Our

  11. Effects of resistance training on tendon mechanical properties and rapid force production in prepubertal children.

    PubMed

    Waugh, C M; Korff, T; Fath, F; Blazevich, A J

    2014-08-01

    Children develop lower levels of muscle force, and at slower rates, than adults. Although strength training in children is expected to reduce this differential, a synchronous adaptation in the tendon must be achieved to ensure forces continue to be transmitted to the skeleton with efficiency while minimizing the risk of strain-related tendon injury. We hypothesized that resistance training (RT) would alter tendon mechanical properties in children concomitantly with changes in force production characteristics. Twenty prepubertal children (age 8.9 ± 0.3 yr) were equally divided into control (nontraining) and experimental (training) groups. The training group completed a 10-wk RT intervention consisting of 2-3 sets of 8-15 plantar flexion contractions performed twice weekly on a recumbent calf-raise machine. Achilles tendon properties (cross-sectional area, elongation, stress, strain, stiffness, and Young's modulus), electromechanical delay (EMD; time between the onset of muscle activity and force), rate of force development (RFD; slope of the force-time curve), and rate of electromyographic (EMG) increase (REI; slope of the EMG time curve) were measured before and after RT. Tendon stiffness and Young's modulus increased significantly after RT in the experimental group only (∼29% and ∼25%, respectively); all other tendon properties were not significantly altered, although there were mean decreases in both peak tendon strain and strain at a given force level (14% and 24%, respectively; not significant) which may have implications for tendon injury risk and muscle fiber mechanics. A decrease of ∼13% in EMD was found after RT for the experimental group, which paralleled the increase in tendon stiffness (r = -0.59); however, RFD and REI were unchanged. The present data show that the Achilles tendon adapts to RT in prepubertal children and is paralleled by a change in EMD, although the magnitude of this change did not appear to be sufficient to influence RFD. These

  12. Changes of calf muscle-tendon properties due to stretching and active movement of children with cerebral palsy--a pilot study.

    PubMed

    Zhao, Heng; Wu, Yi-Ning; Liu, Jie; Ren, Yupeng; Gaebler-Spira, Deborah J; Zhang, Li-Qun

    2009-01-01

    A portable ankle rehabilitation robot with intelligent stretching and game-based active movement training was used to treat the spastic impaired ankle of children with cerebral palsy over six weeks. The subject's calf muscles and Achilles tendon properties were evaluated before and after treatment using ultrasonography and biomechanical measures. It was found that there were decreased Achilles tendon resting length (2.5%), increased cross-sectional area (5.5%), increased stiffness (22.9%), increased Young's modulus (13.8%), decreased soleus muscle fascicular stiffness (53.7%), and decreased medial gastrocnemius fascicular stiffness (46.1%).

  13. Stem Cells for Augmenting Tendon Repair

    PubMed Central

    Gulotta, Lawrence V.; Chaudhury, Salma; Wiznia, Daniel

    2012-01-01

    Tendon healing is fraught with complications such as reruptures and adhesion formation due to the formation of scar tissue at the injury site as opposed to the regeneration of native tissue. Stem cells are an attractive option in developing cell-based therapies to improve tendon healing. However, several questions remain to be answered before stem cells can be used clinically. Specifically, the type of stem cell, the amount of cells, and the proper combination of growth factors or mechanical stimuli to induce differentiation all remain to be seen. This paper outlines the current literature on the use of stem cells for tendon augmentation. PMID:22190960

  14. Low Concentration of Sodium Butyrate from Ultrabraid+NaBu suture, Promotes Angiogenesis and Tissue Remodelling in Tendon-bones Injury

    PubMed Central

    Liu, Donghui; Andrade, Silvia Passos; Castro, Pollyana Ribeiro; Treacy, John; Ashworth, Jason; Slevin, Mark

    2016-01-01

    Sodium butyrate (NaBu), a form of short-chain fatty acid (SCFA), acts classically as a potent anti-angiogenic agent in tumour angiogenesis models, some authors demonstrated that low concentrations of NaBu may contribute to healing of tendon-bone injury in part at least through promotion of tissue remodelling. Here, we investigated the effects of low-range concentrations of NaBu using in vitro and in vivo assays using angiogenesis as the primary outcome measure and the mechanisms through which it acts. We demonstrated that NaBu, alone or perfused from the UltraBraid+NaBu suture was pro-angiogenic at very low-range doses promoting migration, tube formation and cell invasion in bovine aortic endothelial cells (BAECs). Furthermore, cell exposure to low NaBu concentrations increased expression of proteins involved in angiogenic cell signalling, including p-PKCβ1, p-FAK, p-ERK1/2, p-NFκβ, p-PLCγ1 and p-VEGFR2. In addition, inhibitors of both VEGFR2 and PKCβ1 blocked the angiogenic response. In in vivo assays, low concentrations of NaBu induced neovascularization in sponge implants in mice, evidenced by increased numbers of vessels and haemoglobin content in these implants. The findings in this study indicate that low concentrations of NaBu could be an important compound to stimulate angiogenesis at a site where vasculature is deficient and healing is compromised. PMID:27694930

  15. Effects of isotretinoin treatment on cartilage and tendon thicknesses: an ultrasonographic study.

    PubMed

    Yıldızgören, Mustafa Turgut; Karataş Toğral, Arzu; Baki, Ali Erdem; Ekiz, Timur

    2015-07-01

    Effects of retinoic acid on collagen synthesis and cartilage have previously been shown. However, its effects on cartilage and tendons in humans have not been studied yet. Therefore, in order to provide a morphologic insight, the aim of this study was to measure femoral cartilage, Achilles and supraspinatus tendon thicknesses in patients under systemic isotretinoin treatment by using ultrasound. Fifteen patients (nine F, six M) who used isotretinoin for their acnes were included. All patients were treated with isotretinoin 0.5 mg/kg/day for the first month, and the dosage was escalated up to 1 mg/kg/day thereafter. Distal femoral cartilage, supraspinatus, and Achilles tendons thicknesses have been evaluated both before the treatment and at the end of the third month. Femoral cartilage thicknesses were assessed from three midpoints bilaterally; medial condyle, lateral condyle, and intercondylar area. Short/long-axis diameters and cross-sectional area of the Achilles tendons and axial tendon thicknesses of supraspinatus tendon were evaluated from the nondominant side. The mean age of the patients was 20.1 ± 4.9 years, and body mass index was 21.7 ± 2.5 kg/m(2). Although posttreatment cartilage measurements of 30 knees were lower for the three midpoints, it reached significance only for lateral condyle (p = 0.05). In addition, posttreatment tendon measurements were not statistically significant compared with pretreatment values (all p > 0.05). Systemic isotretinoin treatment seems to make cartilage thinner. Further studies considering histological and molecular evaluations with more sample sizes are awaited.

  16. Low-power-laser therapy used in tendon damage

    NASA Astrophysics Data System (ADS)

    Strupinska, Ewa

    1996-03-01

    The following paper covers evaluation of low-power laser therapy results in chronic Achilles tendon damage and external Epicondylalia (tennis elbow). Fifty patients with Achilles damage (18 women and 32 men, age average 30, 24 plus or minus 10, 39 years) and fifty patients having external Epicondyalgiae (31 women and 19 men, age average 44, 36 plus or minus 10, 88 years) have been examined. The patients were irradiated by semiconductor infrared laser wavelength 904 nm separately or together with helium-neon laser wavelength 632.8 nm. The results of therapy have been based on the patient's interviews and examinations of patients as well as on the Laitinen pain questionnaire. The results prove analgesic effects in usage of low- power laser radiation therapy can be obtained.

  17. Nanoparticles for Tendon Healing and Regeneration: Literature Review

    PubMed Central

    Parchi, Paolo D.; Vittorio, Orazio; Andreani, Lorenzo; Battistini, Pietro; Piolanti, Nicola; Marchetti, Stefano; Poggetti, Andrea; Lisanti, Michele

    2016-01-01

    Tendon injuries are commonly met in the emergency department. Unfortunately, tendon tissue has limited regeneration potential and usually the consequent formation of scar tissue causes inferior mechanical properties. Nanoparticles could be used in different way to improve tendon healing and regeneration, ranging from scaffolds manufacturing (increasing the strength and endurance or anti-adhesions, anti-microbial, and anti-inflammatory properties) to gene therapy. This paper aims to summarize the most relevant studies showing the potential application of nanoparticles for tendon tissue regeneration. PMID:27597828

  18. Pitfalls during