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Sample records for tendon tears comparison

  1. 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

  2. Proximal Biceps Tendon and Rotator Cuff Tears.

    PubMed

    Virk, Mandeep S; Cole, Brian J

    2016-01-01

    The long head of biceps tendon (LHBT) is frequently involved in rotator cuff tears and can cause anterior shoulder pain. Tendon hypertrophy, hourglass contracture, delamination, tears, and tendon instability in the bicipital groove are common macroscopic pathologic findings affecting the LHBT in the presence of rotator cuff tears. Failure to address LHBT disorders in the setting of rotator cuff tear can result in persistent shoulder pain and poor satisfaction after rotator cuff repair. Tenotomy or tenodesis of the LHBT are effective options for relieving pain arising from the LHBT in the setting of reparable and selected irreparable rotator cuff tears.

  3. After rotator cuff tears, the remaining (intact) tendons are mechanically altered.

    PubMed

    Perry, Stephanie M; Getz, Charles L; Soslowsky, Louis J

    2009-01-01

    Although presumed, damage in the remaining (intact) rotator cuff tendons in the presence of an isolated supraspinatus tendon tear or multiple tendon tear has not been well studied. This study used an animal model of multiple rotator cuff tendon tears to investigate alterations in the remaining (intact) tendon mechanical properties at 4 and 8 weeks after injury. Twenty-four rats served as uninjured controls, whereas 72 were divided among 3 tendon detachment groups: supraspinatus tendon detachment, supraspinatus + infraspinatus tendon detachment, and supraspinatus + subscapularis tendon detachment. The remaining (intact) rotator cuff tendons had decreased mechanical properties in the presence of rotator cuff tears. The remaining (intact) subscapularis and infraspinatus tendon cross-sectional areas increased, whereas tendon modulus decreased after tears of both 1 and 2 tendons. The remaining (intact) tendon cross-sectional areas continued to increase with time after injury. These alterations could potentially lead to further tendon damage and tear progression.

  4. Irreparable Rotator Cuff Tears: Restoring Joint Kinematics by Tendon Transfers

    PubMed Central

    Greenspoon, Joshua A.; Millett, Peter J.; Moulton, Samuel G.; Petri, Maximilian

    2016-01-01

    Background: Tendon transfers can be a surgical treatment option in managing younger, active patients with massive irreparable rotator cuff tears. The purpose of this article is to provide an overview of the use of tendon transfers to treat massive irreparable rotator cuff tears and to summarize clinical outcomes. Methods: A selective literature search was performed and personal surgical experiences are reported. Results: Latissimus dorsi transfers have been used for many years in the management of posterosuperior rotator cuff tears with good reported clinical outcomes. It can be transferred without or with the teres major (L’Episcopo technique). Many surgical techniques have been described for latissimus dorsi transfer including single incision, double incision, and arthroscopically assisted transfer. Transfer of the pectoralis major tendon is the most common tendon transfer procedure performed for anterosuperior rotator cuff deficiencies. Several surgical techniques have been described, however transfer of the pectoralis major beneath the coracoid process has been found to most closely replicate the force vector that is normally provided by the intact subscapularis. Conclusion: Tendon transfers can be used successfully in the management of younger patients with massive irreparable rotator cuff tears and minimal glenohumeral arthritis. Improvements in clinical outcomes scores and range of motion have been demonstrated. This can delay arthroplasty, which is of particular importance for younger patients with high functional demands. PMID:27708730

  5. Interstitial Tear of the Subscapularis Tendon, Arthroscopic Findings and Technique of Repair

    PubMed Central

    Saremi, Hossein

    2016-01-01

    Tears of the subscapularis tendon have been significantly recognized as a source of shoulder pain and dysfunction in the past decade, thanks to arthroscopic evaluation of the shoulder and biomechanical and anatomical studies of the tendon. Current classification of subscapularis tendon tear is based on insertion site of the tendon. Recently, a classification for non-insertional types of subscapularis tendon tear has been published. Interstitial tear of subscapularis tendon has not been described in classifications available in the literature. This report describes significant interstitial tear of the subscapularis tendon. This tear looks normal in superior, bursal and articular sides. Then its specific arthroscopic findings as “Air bag sign” and repair technique of the pathology is explained. PMID:27200399

  6. Subpectoral biceps tenodesis for bicipital tendonitis with SLAP tear.

    PubMed

    Gupta, Anil K; Chalmers, Peter N; Klosterman, Emma L; Harris, Joshua D; Bach, Bernard R; Verma, Nikhil N; Cole, Brian J; Romeo, Anthony A

    2015-01-01

    The purpose of this study was to evaluate the outcomes of patients undergoing subpectoral biceps tenodesis for bicipital tendonitis with a superior labral anterior-posterior (SLAP) tear. Patients undergoing primary subpectoral biceps tenodesis for arthroscopically confirmed SLAP tears with signs or findings of bicipital tendonitis were included. An independent observer collected data prospectively as part of a data repository, which was then analyzed retrospectively. Primary outcome measures were the American Shoulder and Elbow Surgeons (ASES) score and pain relief via visual analog scale (VAS). Secondary outcome measures included the Simple Shoulder Test (SST), Constant, Single Assessment Numeric Evaluation (SANE), and Short Form 12 (SF-12) scores. Twenty-eight patients with a mean±SD age of 43.7±13.4 years and a mean±SD follow-up of 2.0±1.0 years met inclusion criteria. Workers' compensation was involved with 43% of cases, and 46% of the included patients were manual laborers. Eight (32%) patients were athletes, and 88% of the athletes were overhead athletes. Intraoperatively, 15 (54%) patients had type I SLAP tears, 10 (36%) had type II SLAP tears, 1 (3%) had a type III SLAP tear, and 2 (7%) had type IV SLAP tears. Significant improvements were seen in the following outcome measures pre- vs postoperatively: ASES score (58±23 vs 89±18; P=.001), SST score (6.3±3.6 vs 10.6±3.3; P=.001), SANE score (54±24 vs 88±25; P=.003), VAS score (3.8±2.0 vs 1.1±1.8; P=.001), SF-12 overall score (35±6 vs 42±6; P=.001), and SF-12 physical component score (39±6 vs 50±10; P=.001). Overall satisfaction was excellent in 80% of patients. Subpectoral biceps tenodesis demonstrates excellent clinical outcomes in select patients with SLAP tears. [Orthopedics. 2015; 38(1):e48-e53.].

  7. THE CLINICAL, FUNCTIONAL AND BIOMECHANICAL PRESENTATION OF PATIENTS WITH SYMPTOMATIC HIP ABDUCTOR TENDON TEARS

    PubMed Central

    Retheesh, Theertha; Mutreja, Rinky; Janes, Gregory C.

    2016-01-01

    Background Hip abductor tendon (HAT) tearing is commonly implicated in greater trochanteric pain syndrome (GTPS), though limited information exists on the disability associated with this condition and specific presentation of these patients. Purpose To describe the clinical, functional and biomechanical presentation of patients with symptomatic HAT tears. Secondary purposes were to investigate the association between these clinical and functional measures, and to compare the pain and disability reported by HAT tear patients to those with end-stage hip osteoarthritis (OA). Study Design Prospective case series. Methods One hundred forty-nine consecutive patients with symptomatic HAT tears were evaluated using the Harris (HHS) and Oxford (OHS) Hip Scores, SF-12, an additional series of 10 questions more pertinent to those with lateral hip pain, active hip range of motion (ROM), maximal isometric hip abduction strength, six-minute walk capacity and 30-second single limb stance (SLS) test. The presence of a Trendelenburg sign and pelvis-on-femur (POF) angle were determined via 2D video analysis. An age matched comparative sample of patients with end-stage hip OA was recruited for comparison of all patient-reported outcome scores. Independent t-tests investigated group and limb differences, while analysis of variance evaluated pain changes during the functional tests. Pearson's correlation coefficients investigated the correlation between clinical measures in the HAT tear group. Results No differences existed in patient demographics and patient-reported outcome scores between HAT tear and hip OA cohorts, apart from significantly worse SF-12 mental subscale scores (p = 0.032) in the HAT tear group. Patients with HAT tears demonstrated significantly lower (p < 0.05) hip abduction strength and active ROM in all planes of motion on their affected limb. Pain significantly increased throughout the 30-second SLS test for the HAT tear group, with 57% of HAT tear patients

  8. US appearance of partial-thickness supraspinatus tendon tears: Application of the string theory. Pictorial essay

    PubMed Central

    Guerini, H.; Fermand, M.; Godefroy, D.; Feydy, A.; Chevrot, A.; Morvan, G.; Gault, N.; Drapé, J.L.

    2012-01-01

    The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination. A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT). PMID:23396264

  9. US appearance of partial-thickness supraspinatus tendon tears: Application of the string theory. Pictorial essay.

    PubMed

    Guerini, H; Fermand, M; Godefroy, D; Feydy, A; Chevrot, A; Morvan, G; Gault, N; Drapé, J L

    2012-02-01

    The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination.A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT).

  10. Full-thickness tears of the supraspinatus tendon: A three-dimensional finite element analysis.

    PubMed

    Quental, C; Folgado, J; Monteiro, J; Sarmento, M

    2016-12-08

    Knowledge regarding the likelihood of propagation of supraspinatus tears is important to allow an early identification of patients for whom a conservative treatment is more likely to fail, and consequently, to improve their clinical outcome. The aim of this study was to investigate the potential for propagation of posterior, central, and anterior full-thickness tears of different sizes using the finite element method. A three-dimensional finite element model of the supraspinatus tendon was generated from the Visible Human Project data. The mechanical behaviour of the tendon was fitted from experimental data using a transversely isotropic hyperelastic constitutive model. The full-thickness tears were simulated at the supraspinatus tendon insertion by decreasing the interface area. Tear sizes from 10% to 90%, in 10% increments, of the anteroposterior length of the supraspinatus footprint were considered in the posterior, central, and anterior regions of the tendon. For each tear, three finite element analyses were performed for a supraspinatus force of 100N, 200N, and 400N. Considering a correlation between tendon strain and the risk of tear propagation, the simulated tears were compared qualitatively and quantitatively by evaluating the volume of tendon for which a maximum strain criterion was not satisfied. The finite element analyses showed a significant impact of tear size and location not only on the magnitude, but also on the patterns of the maximum principal strains. The mechanical outcome of the anterior full-thickness tears was consistently, and significantly, more severe than that of the central or posterior full-thickness tears, which suggests that the anterior tears are at greater risk of propagating than the central or posterior tears.

  11. Exogenous collagen cross-linking recovers tendon functional integrity in an experimental model of partial tear.

    PubMed

    Fessel, Gion; Wernli, Jeremy; Li, Yufei; Gerber, Christian; Snedeker, Jess G

    2012-06-01

    We investigated the hypothesis that exogenous collagen cross-linking can augment intact regions of tendon to mitigate mechanical propagation of partial tears. We first screened the low toxicity collagen cross-linkers genipin, methylglyoxal and ultra-violet (UV) light for their ability to augment tendon stiffness and failure load in rat tail tendon fascicles (RTTF). We then investigated cross-linking effects in load bearing equine superficial digital flexor tendons (SDFT). Data indicated that all three cross-linking agents augmented RTTF mechanical properties but reduced native viscoelasticity. In contrast to effects observed in fascicles, methylglyoxal treatment of SDFT detrimentally affected tendon mechanical integrity, and in the case of UV did not alter tendon mechanics. As in the RTTF experiments, genipin cross-linking of SDFT resulted in increased stiffness, higher failure loads and reduced viscoelasticity. Based on this result we assessed the efficacy of genipin in arresting tendon tear propagation in cyclic loading to failure. Genipin cross-linking secondary to a mid-substance biopsy-punch significantly reduced tissue strains, increased elastic modulus and increased resistance to fatigue failure. We conclude that genipin cross-linking of injured tendons holds potential for arresting tendon tear progression, and that implications of the treatment on matrix remodeling in living tendons should now be investigated.

  12. Distribution and expression of type VI collagen and elastic fibers in human rotator cuff tendon tears.

    PubMed

    Thakkar, Dipti; Grant, Tyler M; Hakimi, Osnat; Carr, Andrew J

    2014-01-01

    There is increasing evidence for a progressive extracellular matrix change in rotator cuff disease progression. Directly surrounding the cell is the pericellular matrix, where assembly of matrix aggregates typically occurs making it critical in the response of tendon cells to pathological conditions. Studies in animal models have identified type VI collagen, fibrillin-1 and elastin to be located in the pericellular matrix of tendon and contribute in maintaining the structural and biomechanical integrity of tendon. However, there have been no reports on the localization of these proteins in human tendon biopsies. This study aimed to characterize the distribution of these ECM components in human rotator cuffs and gain greater insight into the relationship of pathology to tear size by analyzing the distribution and expression profiles of these ECM components. Confocal microscopy confirmed the localization of these structural molecules in the pericellular matrix of the human rotator cuff. Tendon degeneration led to an increased visibility of these components with a significant disorganization in the distribution of type VI collagen. At the genetic level, an increase in tear size was linked to an increased transcription of type VI collagen and fibrillin-1 with no significant alteration in the elastin levels. This is the first study to confirm the localization of type VI collagen, elastin and fibrillin-1 in the pericellular region of human supraspinatus tendon and assesses the effect of tendon degeneration on these structures, thus providing a useful insight into the composition of human rotator cuff tears which can be instrumental in predicting disease prognosis.

  13. Latissimus Dorsi Tendon Transfer with GraftJacket® Augmentation to Increase Tendon Length for an Irreparable Rotator Cuff Tear

    PubMed Central

    2017-01-01

    Massive irreparable rotator cuff tears can be reconstructed with latissimus dorsi tendon transfers (LDTT). Although uncommon, the natural length of the latissimus dorsi tendon (LDT) could be insufficient for transfer even after adequate soft tissue releases. Descriptions of cases where grafts were needed to lengthen the LDT are therefore rare. We located only two reports of the use of an acellular dermal matrix to increase effective tendon length in tendon transfers about the shoulder: (1) GraftJacket patch for a pectoralis major tendon reconstruction and (2) ArthroFlex® patch for LDTT. Both of these brands of allograft patches are obtained from human cadavers. These products are usually used to cover soft tissue repairs and offer supplemental support rather than for increasing tendon length. Extending the LDTT with GraftJacket to achieve adequate length, to our knowledge, has not been reported in the literature. We report the case of a 50-year-old male who had a massive, irreparable left shoulder rotator cuff tear that was reconstructed with a LDTT. The natural length of his LDT was insufficient for transfer. This unexpected situation was rectified by sewing two patches of GraftJacket to the LDT. The patient had greatly improved shoulder function at two-year follow-up. PMID:28194290

  14. RESULTS FROM ARTHROSCOPIC REPAIR OF ISOLATED TEARS OF THE SUBSCAPULARIS TENDON

    PubMed Central

    Godinho, Glaydson Gomes; de Oliveira França, Flávio; Freita, José Márcio Alves; Santos, Flávio Márcio Lago; dos Santos, Ricardo Barreto Monteiro; Taglietti, Thiago Martins; Guevara, Carlos Leonidas Escobar

    2015-01-01

    Objective: To evaluate the functional and clinical outcomes and identify prognostic factors in patients undergoing arthroscopic repair of isolated tears of the subscapularis tendon. Methods: Between January 2003 and May 2009, we identified 18 shoulders with isolated tears or deinsertions that were complete or affected at least one third of the subscapularis tendon and underwent arthroscopic repair. Results: Three shoulders (17%) showed lesions in the upper third of the subscapularis; nine shoulders (50%) showed lesions in the upper two thirds; and six shoulders (33%) presented complete tears. In comparing the range of lateral rotation of the injured shoulder between before surgery and the time of the reevaluation, there was no statistical difference (p = 0.091). The LHBT was damaged in 11 shoulders (61%). According to the Constant score validation, we had excellent and good results in 83% of the cases and 17% were reasonable. The reevaluations on three patients showed re-tearing on MRI. Acromioplasty was performed on ten patients and this procedure did not represent statistical differences in the final results (p = 0.57). Conclusions: There was no statistically significant difference in relation to preoperative lateral rotation between the injured shoulder and the contralateral side. There was no significant loss of lateral rotation after surgery. The LHBT may be normal in deinsertions of the subscapularis tendon. Acromioplasty did not influence the results. The re-tearing rate for arthroscopic repair of the subscapularis tendon was 16.6%. PMID:27042642

  15. Influence of tendon tears on ultrasound echo intensity in response to loading

    PubMed Central

    Frisch, Kayt E.; Marcu, David; Baer, Geoffrey S.; Thelen, Darryl G.; Vanderby, Ray

    2014-01-01

    Acoustoelastic (AE) ultrasound image analysis is a promising non-invasive approach that uses load-dependent echo intensity changes to characterize stiffness of tendinous tissue. The purpose of this study was to investigate whether AE can detect localized changes in tendon stiffness due to partial and full-thickness tendon tears. Ovine infraspinatus tendons with different levels of damage (Intact, 33%, 66% and full thickness cuts initiated on the articular and bursal sides) were cyclically loaded in a mechanical testing system while cine ultrasound images were recorded. The load-induced changes in echo intensity on the bursal and articular side of the tendon were determined. Consistent with AE theory, the undamaged tendons exhibited an increase in echo intensity with tendon loading, reflecting the strain-stiffening behavior of the tissue. In the intact condition, the articular region demonstrated a significantly greater increase in echo intensity during loading than the bursal region. Cuts initiated on the bursal side resulted in a progressive decrease in echo intensity of the adjacent tissue, likely reflecting the reduced load transmission through that region. However, image intensity information was less sensitive for identifying load transmission changes that result from partial thickness cuts initiated on the articular side. We conclude that AE approaches may be useful to quantitatively assess load-dependent changes in tendon stiffness, and that disruption of AE behavior may be indicative of substantial tendon damage. PMID:25468301

  16. Adipogenic and myogenic gene expression in rotator cuff muscle of the sheep after tendon tear.

    PubMed

    Frey, Eric; Regenfelder, Felix; Sussmann, Patrick; Zumstein, Matthias; Gerber, Christian; Born, Walter; Fuchs, Bruno

    2009-04-01

    Chronic rotator cuff tendon tears lead to fatty infiltration and muscle atrophy with impaired physiological functions of the affected muscles. However, the cellular and molecular mechanisms of corresponding pathophysiological processes remain unknown. The purpose of this study was to characterize the expression pattern of adipogenic (PPARgamma, C/EBPbeta) and myogenic (myostatin, myogenin, Myf-5) transcription factors in infraspinatus muscle of sheep after tenotomy, implantation of a tension device, refixation of the tendon, and rehabilitation, reflecting a model of chronic rotator cuff tears. In contrast to human patients, the presented sheep model allows a temporal evaluation of the expression of a given marker in the same individual over time. Semiquantitative RT/PCR analysis of PPARgammaã, myostatin, myogenin, Myf-5, and C/EBPbeta transcript levels was carried out with sheep muscle biopsy-derived total RNA. We found a significantly increased expression of Myf-5 and PPARgamma after tenotomy and a significant change for Myf-5 and C/EBPbeta after continuous traction and refixation. This experimental sheep model allows the molecular analysis of pathomechanisms of muscular changes after rotator cuff tear. The results point to a crucial role of the transcription factors PPARgamma, C/EBPbeta, and Myf-5 in impairment and regeneration of rotator cuff muscles after tendon tears in sheep.

  17. [Treatment of unrecent patellar tendon tear with semitendinous and gracilis tendons].

    PubMed

    Estrada-Malacón, C A; García-Estrada, G A

    2011-01-01

    The patellar tendon lesion is very important due to the role of this tendon on the conformation of the extensor mechanism of the quadriceps. When the terminal end of this mechanism is injured, the extensor function of the knee is completely lost and thus the functional capability of the involved limb is completely disrupted.

  18. Longitudinal split tear of the extensor pollicis brevis tendon: report of 2 cases.

    PubMed

    Kroonen, Leo T; Ferguson, Christopher; Ketschke, Rhett A

    2015-02-01

    Two patients presented with radial-sided wrist pain and longitudinal split tears of the extensor pollicis brevis tendon. Surgical debridement and repair was performed on the first patient with good results. Early diagnosis in the second patient led to successful treatment with immobilization alone. If diagnostic maneuvers for de Quervain tenosynovitis produce pain in a location other than the radial styloid, advanced imaging should be considered to identify other anatomic causes for the pain.

  19. Bilateral Superior Labrum Anterior to Posterior (SLAP) Tears With Abnormal Anatomy of Biceps Tendon.

    PubMed

    Morris, Dan; Guettler, Joseph; Morris, Sean

    2015-08-01

    There have been several descriptions of variant anatomy of the long head of the biceps tendon (LHBT). A recent literature review identified 8 cases of anomalous intracapsular attachment of the LHBT. In this report, we discuss a distinctive case of a young athlete who presented with symptoms consistent with bilateral superior labrum anterior to posterior (SLAP) tears that were unresponsive to conservative measures. Magnetic resonance imaging and arthroscopic findings of this patient confirmed that the patient had type II SLAP tears, a Buford complex anteriorly, and perhaps most important, confluence of the biceps tendon itself to the undersurface of the capsule within the rotator interval. Our case proposes that anomalous insertion of the LHBT, as well as other labral and biceps anchor variations, are not always a benign finding at the time of arthroscopy. In this particular case, the tethering of the biceps tendon to the capsule is thought to have increased stress on the superior labrum and contributed to the development of the bilateral symptomatic type II SLAP tears that were identified and treated in this young athlete.

  20. The role of the biceps tendon in massive rotator cuff tears.

    PubMed

    Pill, Stephan G; Walch, Gilles; Hawkins, Richard J; Kissenberth, Michael J

    2012-01-01

    Tendinopathy of the long head of the biceps (LHB) tendon commonly occurs in patients with rotator cuff tears, and the inflammation of one head tends to lead to inflammation of the other. Many theories have been proposed regarding the function of the LHB tendon; however, its exact purpose is poorly understood. It has been described as an important stabilizer of the glenohumeral joint, a depressor of the humeral head, and as a vestigial structure. The LHB tendon can be a significant source of pain in patients with rotator cuff tears. The appropriate treatment depends on the patient's age, comorbidities, activity level, extent of disability, the presence of rotator cuff arthropathy, and the quality of the rotator cuff tissue. Conservative treatment is usually attempted first, with modalities such as nonsteroidal anti-inflammatory drugs, corticosteroid injections, physical therapy, and activity modification. If symptoms persist, biceps tenotomy or tenodesis may be combined with rotator cuff repair, depending on the quality of the rotator cuff tissue, the severity of rotator cuff arthropathy, and the willingness of the patient to comply with postoperative immobilization and rehabilitation. Even when rotator cuff repair is not possible, isolated tenotomy or tenodesis of the LHB tendon can provide substantial pain relief.

  1. 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

  2. Regeneration of Full-Thickness Rotator Cuff Tendon Tear After Ultrasound-Guided Injection With Umbilical Cord Blood-Derived Mesenchymal Stem Cells in a Rabbit Model

    PubMed Central

    Park, Gi-Young; Lee, Sang Chul

    2015-01-01

    Rotator cuff tendon tear is one of the most common causes of chronic shoulder pain and disability. In this study, we investigated the therapeutic effects of ultrasound-guided human umbilical cord blood (UCB)-derived mesenchymal stem cell (MSC) injection to regenerate a full-thickness subscapularis tendon tear in a rabbit model by evaluating the gross morphology and histology of the injected tendon and motion analysis of the rabbit’s activity. At 4 weeks after ultrasound-guided UCB-derived MSC injection, 7 of the 10 full-thickness subscapularis tendon tears were only partial-thickness tears, and 3 remained full-thickness tendon tears. The tendon tear size and walking capacity at 4 weeks after UCB-derived MSC injection under ultrasound guidance were significantly improved compared with the same parameters immediately after tendon tear. UCB-derived MSC injection under ultrasound guidance without surgical repair or bioscaffold resulted in the partial healing of full-thickness rotator cuff tendon tears in a rabbit model. Histology revealed that UCB-derived MSCs induced regeneration of rotator cuff tendon tear and that the regenerated tissue was predominantly composed of type I collagens. In this study, ultrasound-guided injection of human UCB-derived MSCs contributed to regeneration of the full-thickness rotator cuff tendon tear without surgical repair. The results demonstrate the effectiveness of local injection of MSCs into the rotator cuff tendon. Significance The results of this study suggest that ultrasound-guided umbilical cord blood-derived mesenchymal stem cell injection may be a useful conservative treatment for full-thickness rotator cuff tendon tear repair. PMID:26371340

  3. Tendon transfer for irreparable rotator cuff tears: indications and surgical rationale

    PubMed Central

    Merolla, Giovanni; Chillemi, Claudio; Franceschini, Vincenzo; Cerciello, Simone; Ippolito, Giorgio; Paladini, Paolo; Porcellini, Giuseppe

    2014-01-01

    Summary Background: treatment of symptomatic irreparable rotator cuff tears is extremely challenging because, at present, there are no ideal solutions to this problem. Many patients respond favorably to nonsurgical treatment. However, when conservative measures fail to improve the patient’s pain and disability, surgery should be considered. Methods: different surgical techniques are available and the choice of the most appropriate procedure depends on the presenting symptoms, age of the patient, functional demand, medical comorbidities, joint stability and presence of arthritic changes. The transposition of the surrounding muscles to replace the rotator cuff function represents a viable option in the treatment of younger patients without glenohumeral osteoarthritis and with severe functional limitation. Purpose: aim of this study is to give an overview of the currently available evidence regarding tendon transfer procedures for irreparable rotator cuff tears. PMID:25767779

  4. Rupture of the distal biceps tendon combined with a supinator muscle tear in a 51-year-old woman: a case report.

    PubMed

    Nayyar, Samir; Quirno, Martin; Hasan, Saqib; Rybak, Leon; Meislin, Robert J

    2011-01-01

    Distal biceps tendon rupture is a relatively uncommon occurrence in the general female population, and to our knowledge, has not been reported in association with a supinator muscle tear. We report a case of 51-year-old woman who experienced sharp pain in her forearm and elbow after lifting a heavy object. History and physical examination raised suspicion for a distal biceps tendon rupture. MRI imaging determined a combined distal biceps tendon tear with a supinator muscle tear with subsequent confirmation at surgery. Surgical repair was performed for the distal biceps tendon only through a single incision approach using the Endobutton technique.

  5. ARTHROSCOPIC REPAIR OF SMALL AND MEDIUM TEARS OF THE SUPRASPINATUS MUSCLE TENDON: EVALUATION OF THE CLINICAL AND FUNCTIONAL OUTCOMES AFTER TWO YEARS OF FOLLOW-UP

    PubMed Central

    Ikemoto, Roberto Yukio; Murachovsky, Joel; Nascimento, Luís Gustavo Prata; Bueno, Rogério Serpone; Almeida, Luis Henrique; Strose, Eric; Castiglia, Marcello Teixeira

    2015-01-01

    Objective: To evaluate the clinical and functional outcomes from arthroscopic repairs on small and medium-sized tears of the supraspinatus muscle tendon. Methods: 129 cases of isolated small and medium tears of the supraspinatus muscle tendon were evaluated retrospectively. The average duration of pain was 29 months. The average joint range of motion comprised active elevation of 136°, lateral rotation of 58° and medial rotation at T12 level; and the preoperative functional UCLA score averaged 17 points. In all the cases, complete repair could be achieved. Results: The average score on the UCLA functional scale in the postoperative period was 32 points. The average length of follow-up was 39 months. Seventy-five cases (58%) had excellent results and 42 (32%) had good results. The average final active elevation was 156° with an average gain of 20°, and the average final lateral rotation was 57° with an average gain of 9°. Both of these were statistically significant (P < 0.05). The patients who underwent tenotomy of the long head of the biceps (LHB), with or without tenodesis, did not present statistically inferior functional outcomes, in comparison with the patients who only underwent decompression and lesion repair (P = 1.00). Fourteen cases (10.8%) presented complications during the postoperative period. Six (4.6%) developed adhesive capsulitis and four (3.1%) presented re-rupture of the tendon, proven by means of magnetic resonance imaging. Conclusions: Arthroscopic repair of small and medium tears of the supraspinatus muscle tendon provided a functional clinical improvement, with good and excellent results in 90% of the cases. PMID:27047846

  6. CLINICAL DIAGNOSIS OF SUBSCAPULARIS TENDON TEAR USING THE BEAR HUG SEMIOLOGICAL MANEUVER

    PubMed Central

    Schiefer, Márcio; Júnior, Yonder Archanjo Ching-San; Silva, Sérgio Maurício; Fontenelle, César; Dias Carvalho, Marcos Genúncio; de Faria, Fabio Garcia; Franco, José Sérgio

    2015-01-01

    Objective: To evaluate the Bear Hug maneuver for clinically diagnosing subscapularis tendon tears, and compare this with other maneuvers described previously (Lift-off, Napoleon and Belly Press). Methods: Forty-nine patients with rotator cuff injuries who had undergone arthroscopy to repair the injury and had previously been assessed using the semiological maneuvers mentioned above were evaluated. Results: The diagnostic values obtained for the Bear Hug test were as follows: sensitivity 75%, specificity 56%, positive predictive value 62%, negative predictive value 70% and accuracy 65%. Conclusion: The highest sensitivity and negative predictive value values were obtained with the Bear Hug test. The highest specificity value was seen with the Lift-off test. The Belly press test gave the greatest specificity, positive predictive and accuracy values. PMID:27047870

  7. Semitendinosus and gracilis free muscle-tendon graft for repair of massive rotator cuff tears: surgical technique

    PubMed Central

    GIGANTE, ANTONIO; BOTTEGONI, CARLO; MILANO, GIUSEPPE; RICCIO, MICHELE; DEI GIUDICI, LUCA

    2016-01-01

    Massive rotator cuff tears are difficult to treat surgically due to retraction, degeneration and fraying of the ends of torn tendons, severe fatty infiltration and atrophy of the respective muscles. Procedures developed to close the gap between the rotator cuff and the greater tuberosity of the humerus, such as soft tissue release may be inadequate for large tears. Human or porcine dermal allografts still have uncertain benefits, and tendon transfers seem to be associated with poor outcomes, donor site morbidity and altered mechanics. Reverse total shoulder arthroplasty has limited durability and is not indicated in young patients with high functional demands. We developed a new technique for repairing massive rotator cuff tears by semitendinosus and gracilis myotendinous grafting. This novel therapeutic option allows massive rotator cuff tears to be repaired using autologous material that is adequate and adaptable, making it possible to cover any width of defect. The technique is low-invasive and not technically demanding, with minimal donor site morbidity. PMID:27900313

  8. 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

  9. Revision Rotator Cuff Reconstruction for Large Tears With Retraction: A Novel Technique Using Autogenous Tendon and Autologous Marrow.

    PubMed

    Skoff, Hillel D

    2015-07-01

    Revision rotator cuff reconstruction for large tears with retraction results in a high rate of recurrent cuff tearing. To try to obtain more consistent results, I conducted a study of a technique that addresses the potential factors involved. Ten patients (7 men, 3 women) were enrolled. Mean age was 58 years. Mean follow-up was 24 months. Mean time between primary and revision cuff surgery was 36 months. The cardinal inclusion criterion was a symptomatic, full-thickness rotator cuff tear with at least 3 cm of retraction in a shoulder that previously underwent rotator cuff repair. Ultrasound was used for postoperative radiographic assessment of cuff integrity. Validated Constant, American Shoulder and Elbow Surgeons (ASES), and University of California Los Angeles (UCLA) shoulder scoring systems were used. Surgical technique included mini-open incision, adequate débridement and mobilization of remaining cuff, reconstitution of cuff defect with autogenous biceps tendon incubated in concentrated autologous bone marrow, and sewing under zero tissue tension. Constant, ASES, and UCLA scores improved significantly (standard error at .001). Ultrasound revealed 0% incidence of full-thickness rotator cuff retearing. In patients with large recurrent retracted rotator cuff tears the technique presented in the current study consistently yields satisfactory clinical results and promotes rotator cuff tissue healing without full-thickness retearing.

  10. Clinics in diagnostic imaging (151). Acromioclavicular joint geyser sign with chronic full-thickness supraspinatus tendon (SST) tear.

    PubMed

    Khor, Andrew Yu Keat; Wong, Steven Bak Siew

    2014-02-01

    An 82-year-old man presented with neck pain, right upper limb radiculopathy and right shoulder pain. Physical examination revealed a soft lump over the right shoulder joint, as well as reduced range of shoulder movements. On magnetic resonance imaging, the soft lump was shown to be a cystic mass over the acromioclavicular joint and was related to a full-thickness supraspinatus tendon tear. This is the classic geyser sign. The pathophysiology and clinical features of the geyser sign, and its imaging features with various imaging modalities, are discussed.

  11. Ultrasound evaluation of the distal migration of the long head of biceps tendon following tenotomy in patients undergoing arthroscopic repair of tears of the rotator cuff.

    PubMed

    Karataglis, D; Papadopoulos, P; Boutsiadis, A; Fotiadou, A; Ditsios, K; Hatzokos, I; Christodoulou, A

    2012-11-01

    This study evaluates the position of the long head of biceps tendon using ultrasound following simple tenotomy, in patients with arthroscopically repaired rotator cuff tears. In total, 52 patients with a mean age of 60.7 years (45 to 75) underwent arthroscopic repair of the rotator cuff and simple tenotomy of the long head of biceps tendon. At two years post-operatively, ultrasound revealed that the tendon was inside the bicipital groove in 43 patients (82.7%) and outside in nine (17.3%); in six of these it was lying just outside the groove and in the remaining three (5.8%) it was in a remote position with a positive Popeye Sign. A dynamic ultrasound scan revealed that the tenotomised tendons had adhered to the surrounding tissues (autotenodesis).The initial condition of the tendon influenced its final position (p < 0.0005). The presence of a Popeye sign was statistically influenced by the pre-operative co-existence of supraspinatus and subscapularis tears (p < 0.0001). It appears that the natural history of the tenotomised long head of biceps tendon is to tenodese itself inside or just outside the bicipital groove, while its pre-operative condition and coexistent subscapularis tears play a significant role in the occurrence of a Popeye sign.

  12. Pectoralis Major Tear with Retracted Tendon: How to Fill the Gap? Reconstruction with Hamstring Autograft and Fixation with an Interference Screw

    PubMed Central

    Messedi, K.; Piétu, G.; Crenn, V.; Gouin, F.

    2017-01-01

    Rupture of the pectoralis major tendon is considered an uncommon injury and a significant number of ruptures are missed or diagnosed late, leading to a chronic tear. We report an open reconstruction technique and its outcomes in a case of chronic and retracted PM tear. At the last follow-up (12 months), the patient was pain-free, with a visual analogic scale at 0 all the time. He was very satisfied concerning the cosmetic and clinical results. The constant score was 93%, the SST value 95%, and the Quick DASH score 4.5. MRI performed one year postoperatively confirmed the continuity between PM tendon and graft, even if the aspect of the distal tendon seemed to be thinner than normal PM tendon. The excellent clinical outcomes at one-year follow-up suggest that PM tear with major tendon retraction can be reliably reconstructed with hamstring autograft, using a bioabsorbable screw to optimize the fixation device. This technique has proven its simplicity and efficiency to fill the gap. PMID:28251005

  13. 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

  14. 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.

  15. Comparison of Medial and Lateral Meniscus Root Tears.

    PubMed

    Koo, Ji Hyun; Choi, Sang-Hee; Lee, Seung Ah; Wang, Joon Ho

    2015-01-01

    The meniscus root plays an essential role in maintaining the circumferential hoop tension and preventing meniscal displacement. Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. However, few studies have directly compared the medial and lateral root tears. To assess the prevalence of meniscal extrusion and its relationship with clinical features in medial and lateral meniscus root tears, we performed a retrospective review of the magnetic resonance imaging (MRI) results of 42 knee patients who had meniscus posterior horn root tears and who had undergone arthroscopic operations. The presence of meniscal extrusion was evaluated and the exact extent was measured from the tibial margin. The results were correlated with arthroscopic findings. Clinical features including patients' ages, joint abnormalities, and previous trauma histories were evaluated. Twenty-two patients had medial meniscus root tears (MMRTs) and twenty patients had lateral meniscus root tears (LMRTs). Meniscal extrusion was present in 18 MMRT patients and one LMRT patient. The mean extent of extrusion was 4.2mm (range, 0.6 to 7.8) in the MMRT group and 0.9mm (range, -1.9 to 3.4) in the LMRT group. Five patients with MMRT had a history of trauma, while 19 patients with LMRT had a history of trauma. Three patients with MMRT had anterior cruciate ligament (ACL) tears, while 19 patients with LMRT had ACL tears. The mean age of the patients was 52 years (range: 29-71 years) and 30 years (range: 14-62 years) in the MMRT and LMRT group, respectively. There was a significant correlation between a MMRT and meniscal extrusion (p<0.0001), and between an ACL tear and LMRT (p<0.0001). A history of trauma was significantly common in LMRT (p<0.0001). LMRT patients were significantly younger than MMRT patients (p<0.0001). Kellgren-Lawrence (K-L) grade differed significantly between MMRT and LMRT group (p<0.0001). Meniscal extrusion is common in

  16. Distal Biceps Tendon Rupture

    DTIC Science & Technology

    2010-06-01

    distal tendon. Although these findings overlap with those seen in tendinopathy , the presence of bone marrow edema at the radial tuberosity and fluid in...the bicipitoradial bursa suggests a partial tear rather than tendinopathy .3 When the distal biceps tendon tear is complete, MR imaging shows

  17. Icariin Promotes Tendon-Bone Healing during Repair of Rotator Cuff Tears: A Biomechanical and Histological Study

    PubMed Central

    Ye, Chenyi; Zhang, Wei; Wang, Shengdong; Jiang, Shuai; Yu, Yuanbin; Chen, Erman; Xue, Deting; Chen, Jianzhong; He, Rongxin

    2016-01-01

    To investigate whether the systematic administration of icariin (ICA) promotes tendon-bone healing after rotator cuff reconstruction in vivo, a total of 64 male Sprague Dawley rats were used in a rotator cuff injury model and underwent rotator cuff reconstruction (bone tunnel suture fixation). Rats from the ICA group (n = 32) were gavage-fed daily with ICA at 0.125 mg/g, while rats in the control group (n = 32) received saline only. Micro-computed tomography, biomechanical tests, serum ELISA (calcium; Ca, alkaline phosphatase; AP, osteocalcin; OCN) and histological examinations (Safranin O and Fast Green staining, type I, II and III collagen (Col1, Col2, and Col3), CD31, and vascular endothelial growth factor (VEGF)) were analyzed two and four weeks after surgery. In the ICA group, the serum levels of AP and OCN were higher than in the control group. More Col1-, Col2-, CD31-, and VEGF-positive cells, together with a greater degree of osteogenesis, were detected in the ICA group compared with the control group. During mechanical testing, the ICA group showed a significantly higher ultimate failure load than the control group at both two and four weeks. Our results indicate that the systematic administration of ICA could promote angiogenesis and tendon-bone healing after rotator cuff reconstruction, with superior mechanical strength compared with the controls. Treatment for rotator cuff injury using systematically-administered ICA could be a promising strategy. PMID:27792147

  18. Icariin Promotes Tendon-Bone Healing during Repair of Rotator Cuff Tears: A Biomechanical and Histological Study.

    PubMed

    Ye, Chenyi; Zhang, Wei; Wang, Shengdong; Jiang, Shuai; Yu, Yuanbin; Chen, Erman; Xue, Deting; Chen, Jianzhong; He, Rongxin

    2016-10-25

    To investigate whether the systematic administration of icariin (ICA) promotes tendon-bone healing after rotator cuff reconstruction in vivo, a total of 64 male Sprague Dawley rats were used in a rotator cuff injury model and underwent rotator cuff reconstruction (bone tunnel suture fixation). Rats from the ICA group (n = 32) were gavage-fed daily with ICA at 0.125 mg/g, while rats in the control group (n = 32) received saline only. Micro-computed tomography, biomechanical tests, serum ELISA (calcium; Ca, alkaline phosphatase; AP, osteocalcin; OCN) and histological examinations (Safranin O and Fast Green staining, type I, II and III collagen (Col1, Col2, and Col3), CD31, and vascular endothelial growth factor (VEGF)) were analyzed two and four weeks after surgery. In the ICA group, the serum levels of AP and OCN were higher than in the control group. More Col1-, Col2-, CD31-, and VEGF-positive cells, together with a greater degree of osteogenesis, were detected in the ICA group compared with the control group. During mechanical testing, the ICA group showed a significantly higher ultimate failure load than the control group at both two and four weeks. Our results indicate that the systematic administration of ICA could promote angiogenesis and tendon-bone healing after rotator cuff reconstruction, with superior mechanical strength compared with the controls. Treatment for rotator cuff injury using systematically-administered ICA could be a promising strategy.

  19. Influence of psychomotor skills and innervation patterns on results of latissimus dorsi tendon transfer for irreparable rotator cuff tears.

    PubMed

    Werner, Clément M L; Ruckstuhl, Thomas; Müller, Roland; Zanetti, Marco; Gerber, Christian

    2008-01-01

    This investigation was performed to analyze the influence of innervation and psychomotor skills on the outcome of latissimus dorsi transfer. Patients with the 10 best and 10 worst results after latissimus dorsi transfer for irreparable rotator cuff tears were selected. All patients meeting the inclusion criteria (n = 12) were subject to a psychomotor test battery (Motorische Leistungsserie) and electromyographic innervation assessment. There was no statistical difference between the 2 groups preoperatively in terms of the commonly tested factors known to influence the results of this procedure adversely. There was a significant difference in both the pattern and selectivity of innervation in the group that had better clinical results. The psychomotor findings were negatively correlated with the range of motion and the strength of the operative shoulder. Function of the operative shoulder could also be predicted by psychomotor function of the uninjured contralateral side. Psychomotor skills testing appears to be a new, potential method by which to predict the outcome of latissimus dorsi transfer.

  20. Inflamed shoulder tendons (image)

    MedlinePlus

    Tearing and inflammation of the tendons of the shoulder muscles can occur in sports which require the ... pitching, swimming, and lifting weights. Most often the shoulder will heal if a break is taken from ...

  1. Partial peroneus longus tendon rupture in professional basketball players: a report of 2 cases.

    PubMed

    Cooper, Mitchell E; Selesnick, F Harlan; Murphy, Brian J

    2002-12-01

    Partial tears of the peroneal tendons are rare. Partial longitudinal tears of the peroneus longus tendon are even more rare. We report on 2 professional basketball players who had partial peroneus longus tendon tears beneath the cuboid. A literature review and discussion of treatment is included.

  2. [Comparison of local acetylcysteine and artificial tears in the management of dry eye syndrome].

    PubMed

    Pokupec, Rajko; Petricek, Igor; Sikić, Jakov; Bradić, Mirna; Popović-Suić, Smiljka; Petricek, Goranka

    2005-01-01

    Dry eye syndrome is a common clinical entity causing difficulties to many people, especially the elderly. Standard substitution therapy with artificial tears may frequently prove inadequate, thus any new treatment modality is highly welcome. The syndrome implies lacrimal hyperosmolality, which in turn results in mucus accumulation in the conjunctival sac causing additional irritation. Locally applied acetylcysteine, a mucolytic, regulates mucus secretion and reduces mucus accumulation. The aim of the study was to compare the efficacy of artificial tear therapy and therapy with local acetylcysteine. The study included 32 patients with the symptoms and signs of dry eye attending our department between March 20 and May 9, 2003. All study patients were on long-term substitution therapy with artificial tears. Upon evaluation of subjective discomforts and objective signs, the patients were switched from artificial tear therapy (Isopto-Tears, Alcon, with polyvinyl alcohol as active ingredient) to therapy with locally applied acetylcysteine (Brunac, Bruschettini). All parameters were re-evaluated at 2-week control visit. Thirty of 32 patients (94%) completed the study with control visit. Of these, 18 (60%) patients reported reduction of subjective discomforts, ten (33%) patients observed no change, and two (7%) patients experienced more discomforts with acetylcysteine than with artificial tear therapy. On objective sign evaluation, 12 (40%) patients showed less discomforts, unchanged condition was recorded in 13 (43%) patients, and five (17%) patients had more discomforts as compared with artificial tear therapy. A statistically significant difference (p=0.05) between artificial tear therapy and acetylcysteine therapy was found for the subjective symptom score but not for the objective sign score. Therapy with acetylcysteine proved more efficient than artificial tears in reducing subjective symptoms but had no effect on the objective signs of dry eye syndrome. The

  3. Biomechanical Comparison of Parallel and Crossed Suture Repair for Longitudinal Meniscus Tears

    PubMed Central

    Milchteim, Charles; Branch, Eric A.; Maughon, Ty; Hughey, Jay; Anz, Adam W.

    2016-01-01

    Background: Longitudinal meniscus tears are commonly encountered in clinical practice. Meniscus repair devices have been previously tested and presented; however, prior studies have not evaluated repair construct designs head to head. This study compared a new-generation meniscus repair device, SpeedCinch, with a similar established device, Fast-Fix 360, and a parallel repair construct to a crossed construct. Both devices utilize self-adjusting No. 2-0 ultra–high molecular weight polyethylene (UHMWPE) and 2 polyether ether ketone (PEEK) anchors. Hypothesis: Crossed suture repair constructs have higher failure loads and stiffness compared with simple parallel constructs. The newer repair device would exhibit similar performance to an established device. Study Design: Controlled laboratory study. Methods: Sutures were placed in an open fashion into the body and posterior horn regions of the medial and lateral menisci in 16 cadaveric knees. Evaluation of 2 repair devices and 2 repair constructs created 4 groups: 2 parallel vertical sutures created with the Fast-Fix 360 (2PFF), 2 crossed vertical sutures created with the Fast-Fix 360 (2XFF), 2 parallel vertical sutures created with the SpeedCinch (2PSC), and 2 crossed vertical sutures created with the SpeedCinch (2XSC). After open placement of the repair construct, each meniscus was explanted and tested to failure on a uniaxial material testing machine. All data were checked for normality of distribution, and 1-way analysis of variance by ranks was chosen to evaluate for statistical significance of maximum failure load and stiffness between groups. Statistical significance was defined as P < .05. Results: The mean maximum failure loads ± 95% CI (range) were 89.6 ± 16.3 N (125.7-47.8 N) (2PFF), 72.1 ± 11.7 N (103.4-47.6 N) (2XFF), 71.9 ± 15.5 N (109.4-41.3 N) (2PSC), and 79.5 ± 25.4 N (119.1-30.9 N) (2XSC). Interconstruct comparison revealed no statistical difference between all 4 constructs regarding maximum

  4. Randomized, masked, in vitro comparison of three commercially available tear film osmometers

    PubMed Central

    Rocha, Guillermo; Gulliver, Eric; Borovik, Armand; Chan, Clara C

    2017-01-01

    Purpose The purpose of this study was to compare the precision and accuracy of commercially available tear film osmometers. Methods Contrived tear solution target values representing the physiological range of tear osmolarity (normal eyes 297 mOsm/L, moderately dry eyes 342 mOsm/L, and severe dry eyes 383 mOsm/L) were constructed using a mix of mono- and divalent electrolytes, metabolites, serum albumin, and pH balanced to 7.4. Solution values were randomized and masked from the investigators during testing. Osmometers (Wescor 5520 Vapro Pressure Osmometer: device A, TearLab Osmolarity System: device B, and i-Med Pharma i-Pen: device C) were calibrated according to manufacturer instructions. Each level was tested 64× on each osmometer across two sites. Accuracy was reported as a correlation coefficient against expected linear dilutions, precision was calculated as percent coefficient of variation. Results Device A reported a correlation with known solutions of r2=0.98, with averages of 305.6±4.0, 352.2±5.5, and 389.8±4.0 mOsm/L, and coefficient of variations (CVs) of 1.3%, 1.6%, and 1.0%, respectively. Device B reported an r2=0.96, with averages of 300.6±3.7, 341.4±7.9, and 376.8±5.1 mOsm/L, and CVs of 1.2%, 2.3%, and 1.4%, respectively. Device C reported an r2=0.03, with averages of 336.4±21.5, 342.0±20.7, and 345.7±22.0 mOsm/L, and CVs of 6.4%, 6.1%, and 6.4%, respectively. Conclusion In this randomized, masked, in vitro study, device A and device B had significantly better accuracy and precision in measuring osmolarity of contrived tear solutions of known target values compared to device C. Device C showed insufficient performance to accurately and precisely delineate osmolarity levels in the physiological range. Furthermore, in vivo studies would be required to compare performance in human subjects. PMID:28184150

  5. 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 ...

  6. Comparison of TGF-β1 in tears and corneal haze following Epi-LASIK with and without mitomycin C

    PubMed Central

    Chen, Jing; Chen, Yi; Han, Su-Ning

    2013-01-01

    AIM To compare transforming growth factor-β1 (TGF-β1) levels in tears and the degree of corneal haze formation following epithelial laser in situ keratomileusis (Epi-LASIK) with and without the use of mitomycin C (MMC) and to investigate the effect of MMC on corneal wound healing. METHODS Thirty-two patients (64 eyes) with high myopia underwent Epi-LASIK surgery, and MMC was randomly used in one eye in each patient. The epithelialization process was observed, and the TGF-β1 level in tears was measured at 1 day, 3, and 7 days postoperatively for comparison with baseline. Corneal haze was graded at 1 month, 3, and 6 months after surgery. RESULTS Mean preoperative spherical equivalent refraction was -8.24±2.18D (range -6.00 to -10.50D) in the MMC group and -7.82±1.55D (range -6.00 to -9.75D) in the non-MMC group. There was no significant difference between the two groups (P=0.38). Mean epithelialization time was (5.02±0.68) days in the MMC group and (4.86±0.57) days in the non-MMC group (P=0.31). Tear fluid TGF-β1 levels were similar before surgery (P=0.34), but were significantly higher in the non-MMC group at 1 day, 3, and 7 days postoperatively (P=0.004, 0.008, and 0.012, respectively). Corneal haze scores 1 month after surgery were significantly higher in the non-MMC group (P=0.03), and similar at 3 and 6 months after surgery (P=0.28 and 0.62, respectively). CONCLUSION MMC did not delay epithelialization. In early postoperative period, lower TGF-β1 levels in tears and a lower grade of corneal haze were observed in the MMC group. Our findings suggest that the ability of MMC to inhibit Epi-LASIK-induced haze might be mediated through TGF-β1 suppression. PMID:23826524

  7. Two cases of chronic knee pain caused by unusual injuries to the popliteus tendon.

    PubMed

    Davalos, Eric A; Barank, David; Varma, Rajeev K

    2016-01-01

    Injuries to the popliteus tendon are less frequent than injuries to the menisci or ligamentous structures of the knee. When they do occur, injuries to the popliteus tendon tend to be the result of trauma and associated with injuries to other components of the knee. The most commonly seen injuries include tears at the musculotendinous junction and avulsion tears at the lateral femoral condyle insertion site. This report presents two unusual injuries of the popliteus tendon in patients with chronic knee pain: an isolated split tear of the tendon and a subluxed tendon residing within the lateral joint space.

  8. Two cases of chronic knee pain caused by unusual injuries to the popliteus tendon

    PubMed Central

    DAVALOS, ERIC A.; BARANK, DAVID; VARMA, RAJEEV K.

    2016-01-01

    Injuries to the popliteus tendon are less frequent than injuries to the menisci or ligamentous structures of the knee. When they do occur, injuries to the popliteus tendon tend to be the result of trauma and associated with injuries to other components of the knee. The most commonly seen injuries include tears at the musculotendinous junction and avulsion tears at the lateral femoral condyle insertion site. This report presents two unusual injuries of the popliteus tendon in patients with chronic knee pain: an isolated split tear of the tendon and a subluxed tendon residing within the lateral joint space. PMID:27386449

  9. Analysis of Pediatric Tendon Injuries in the Hand in Comparison with Adults

    PubMed Central

    Kim, Jin Sung; Sung, Seung Je; Choi, Young Woong

    2017-01-01

    Background The purpose of this study was to identify the epidemiologic characteristics of hand tendon injuries in children and to compare these with those of adults. Methods This retrospective study was conducted on acute traumatic tendon injuries of the hand treated at our institution from 2005 to 2013, based on medical records and X-ray findings. Age, sex, hand injured, mechanism of injury, tendons and zones injured, number of affected digits, and comorbidities and complications were analyzed. Patients were divided into 2 groups: a pediatric group (≤15 years) and an adult group (>15 years). Results Over the 9-year study period, 533 patients were surgically treated for acute traumatic tendon injuries of the hand. In the pediatric group (n=76), being male, the right hand, the extensor tendon, complete rupture, the middle finger, and glass injury predominated in hand tendon injuries. In the adult group (n=457), results were similar, but injury to the index finger and knife injury were the most common. An accompanying fracture was more common in the adult group and complication rates were non-significantly different. Conclusions This comparative analysis revealed no significant epidemiologic intergroup differences. The belief that pediatric tendon injuries tend to be less severe is misplaced, and careful physical examination and exploration should be conducted in pediatric cases of hand injury. PMID:28352603

  10. Antibacterial activity of rifamycins for M. smegmatis with comparison of oxidation and binding to tear lipocalin.

    PubMed

    Staudinger, Tamara; Redl, Bernhard; Glasgow, Ben J

    2014-04-01

    A mutant of Mycobacterium smegmatis is a potential class I model substitute for Mycobacterium tuberculosis. Because not all of the rifamycins have been tested in this organism, we determined bactericidal profiles for the 6 major rifamycin derivatives. The profiles closely mirrored those established for M. tuberculosis. Rifalazil was confirmed to be the most potent rifamycin. Because the tuberculous granuloma presents a harshly oxidizing environment we explored the effects of oxidation on rifamycins. Mass spectrometry confirmed that three of the six major rifamycins showed autoxidation in the presence of trace metals. Oxidation could be monitored by distinctive changes including isosbestic points in the ultraviolet-visible spectrum. Oxidation of rifamycins abrogated anti-mycobacterial activity in M. smegmatis. Protection from autoxidation was conferred by binding susceptible rifamycins to tear lipocalin, a promiscuous lipophilic protein. Rifalazil was not susceptible to autoxidation but was insoluble in aqueous solution. Solubility was enhanced when complexed to tear lipocalin and was accompanied by a spectral red shift. The positive solvatochromism was consistent with robust molecular interaction and binding. Other rifamycins also formed a complex with lipocalin, albeit to a lesser extent. Protection from oxidation and enhancement of solubility with protein binding may have implications for delivery of select rifamycin derivatives.

  11. Antibacterial Activity of Rifamycins for M. Smegmatis with Comparison of Oxidation and Binding to Tear Lipocalin

    PubMed Central

    Staudinger, Tamara; Redl, Bernhard; Glasgow, Ben J.

    2014-01-01

    A mutant of Mycobacterium smegmatis is a potential class I model substitute for Mycobacterium tuberculosis. Because not all of the rifamycins have been tested in this organism, we determined bactericidal profiles for the 6 major rifamycin derivatives. The profiles closely mirrored that established for Mycobacterium tuberculosis. Rifalazil was confirmed to be the most potent rifamycin. Because the tuberculous granuloma presents a harshly oxidizing environment we explored the effects of oxidation on rifamycins. Mass spectrometry confirmed that three of the six major rifamycins showed autoxidation in the presence of trace metals. Oxidation could be monitored by distinctive changes including isosbestic points in the ultraviolet-visible spectrum. Oxidation of rifamycins abrogated antimycobacterial activity in Mycobacterium smegmatis. Protection from autoxidation was conferred by binding susceptible rifamycins to tear lipocalin, a promiscuous lipophilic protein. Rifalazil was not susceptible to autoxidation but was insoluble in aqueous. Solubility was enhanced when complexed to tear lipocalin and was accompanied by a spectral red shift. The positive solvatochromism was consistent with robust molecular interaction and binding. Other rifamycins also formed a complex with lipocalin, albeit to a lesser extent. Protection from oxidation and enhancement of solubility with protein binding may have implications for delivery of select rifamycin derivatives. PMID:24530503

  12. Comparison of Aspect Ratio Effects on Neoclassical Tearing Modes Between DIII-D and NSTX

    NASA Astrophysics Data System (ADS)

    La Haye, R. J.; Buttery, R. J.; Gerhardt, S. P.; Sabbagh, S. A.; Brennan, D. P.

    2010-11-01

    Experimental data is analyzed in which m/n=2/1 neoclassical tearing modes self-stabilized; this ``marginal point'' is valuable for evaluating the relative importance of the terms in the balanced Modified Rutherford equation. DIII-D and NSTX have similar cross-sectional area and shape except for the large difference in aspect ratio. The aspect ratio effects for NTMs explicitly occur in the MRE in the destabilizing helically perturbed bootstrap current term, in the small island stabilizing effects, and in the stabilizing curvature term. The marginal island width on NSTX at q95˜8 is about three times the ion banana width. This agrees with the q95˜4 data on DIII-D but is a larger multiple than for DIII-D at q95˜7. The balance in the MRE indicates that while the stabilizing effect of the curvature term in DIII-D is negligible, it is important in NSTX. The temporal behavior of the mode suggests NSTX operates closer to marginal classical tearing stability, but benefits from the stabilizing effect of curvature.

  13. Effect of glenohumeral abduction angle on the mechanical interaction between the supraspinatus and infraspinatus tendons for the intact, partial-thickness torn, and repaired supraspinatus tendon conditions.

    PubMed

    Andarawis-Puri, Nelly; Kuntz, Andrew F; Ramsey, Matthew L; Soslowsky, Louis J

    2010-07-01

    Rotator cuff tears are difficult to manage because of the structural and mechanical inhomogeneity of the supraspinatus tendon. Previously, we showed that with the arm at the side, the supraspinatus and infraspinatus tendons mechanically interact such that conditions that increase supraspinatus tendon strain, such as load or full-thickness tears, also increase infraspinatus tendon strain. This suggests that the infraspinatus tendon may shield the supraspinatus tendon from further injury while becoming at increased risk of injury itself. In this study, the effect of glenohumeral abduction angle on the interaction between the two tendons was evaluated for supraspinatus tendon partial-thickness tears and two repair techniques. Principal strains were quantified in both tendons for 0 degrees , 30 degrees , and 60 degrees of glenohumeral abduction. Results showed that interaction between the two tendons is interrupted by an increase in abduction angle for all supraspinatus tendon conditions evaluated. Infraspinatus tendon strain was lower at 30 degrees and 60 degrees than at 0 degrees abduction angle. In conclusion, interaction between the supraspinatus and infraspinatus tendons is interrupted with increase in abduction angle. Additionally, 30 degrees abduction should be further evaluated for management of rotator cuff tears and repairs as it is the angle at which both supraspinatus and infraspinatus tendon strain is decreased.

  14. SLAP Tears

    MedlinePlus

    ... caused by acute trauma or by repetitive shoulder motion. An acute SLAP injury may result from: • A ... labrum tears as a result of repeated shoulder motion. This cross-section view of the shoulder socket ...

  15. Tear System

    MedlinePlus

    ... the eyelids. A thorough examination by an ophthalmic plastic surgeon can determine the cause of tearing and ... a dacryocystorhinostomy or DCR, look for an ophthalmic plastic reconstructive and cosmetic surgeon who specializes in the ...

  16. Nonlinear interaction of tearing modes: a comparison between the tokamak and the reversed field pinch configurations

    SciTech Connect

    Holmes, J.A.; Carreras, B.A.; Hender, T.C.; Hicks, H.R.; Lynch, V.E.; An, Z.G.; Diamond, P.H.

    1984-04-01

    The multiple helicity nonlinear interaction of resistive tearing modes is compared for the tokamak and reversed field pinch configurations using the magnetohydrodynamic equations. Unlike the case of the tokamak disruption, for which this interaction is destabilizing when islands overlap, the nonlinear coupling of the dominant helicities is shown to be a stabilizing influence in the reversed field pinch. The behavior of the coupled instabilities in the two configurations can be understood as a consequence of the stability properties of the nonlinearly driven modes. In the case of the tokamak disruption, quasi-linear effects linearly destabilize the dominant driven mode, which then feeds energy to the driving mode. For the reversed field pinch the driven modes remain stable, acting as a brake on the growth of the dominant instabilities than was observed in single helicity studies.

  17. Comparison between three methods to value lower tear meniscus measured by image software

    NASA Astrophysics Data System (ADS)

    García-Resúa, Carlos; Pena-Verdeal, Hugo; Lira, Madalena; Oliveira, M. Elisabete Real; Giráldez, María. Jesús; Yebra-Pimentel, Eva

    2013-11-01

    To measure different parameters of lower tear meniscus height (TMH) by using photography with open software of measurement. TMH was addressed from lower eyelid to the top of the meniscus (absolute TMH) and to the brightest meniscus reflex (reflex TMH). 121 young healthy subjects were included in the study. The lower tear meniscus was videotaped by a digital camera attached to a slit lamp. Three videos were recorded in central meniscus portion on three different methods: slit lamp without fluorescein instillation, slit lamp with fluorescein instillation and TearscopeTM without fluorescein instillation. Then, a masked observed obtained an image from each video and measured TMH by using open source software of measurement based on Java (NIH ImageJ). Absolute central (TMH-CA), absolute with fluorescein (TMH-F) and absolute using the Tearscope (TMH-Tc) were compared each other as well as reflex central (TMH-CR) and reflex Tearscope (TMH-TcR). Mean +/- S.D. values of TMH-CA, TMH-CR, TMH-F, TMH-Tc and TMH-TcR of 0.209 +/- 0.049, 0.139 +/- 0.031, 0.222 +/- 0.058, 0.175 +/- 0.045 and 0.109 +/- 0.029 mm, respectively were found. Paired t-test was performed for the relationship between TMH-CA - TMH-CR, TMH-CA - TMH-F, TMH-CA - TMH-Tc, TMH-F - TMH-Tc, TMH-Tc - TMH-TcR and TMH-CR - TMH-TcR. In all cases, it was found a significant difference between both variables (all p < 0.008). This study showed a useful tool to objectively measure TMH by photography. Eye care professionals should maintain the same TMH parameter in the follow-up visits, due to the difference between them.

  18. MR Imaging and US of the Wrist Tendons.

    PubMed

    Plotkin, Benjamin; Sampath, Srihari C; Sampath, Srinath C; Motamedi, Kambiz

    2016-10-01

    The tendons of the wrist are commonly symptomatic. They can be injured, infected, or inflamed. Magnetic resonance imaging and ultrasonography are useful tools for evaluating the wrist. Pathologic conditions of the wrist tendons include de Quervain tenosynovitis, extensor carpi ulnaris tendinopathy, rheumatoid tenosynovitis, infectious synovitis, tendon tears, hydroxyapatite deposition disease, intersection syndrome, tenosynovial giant cell tumor, and fibroma of the tendon sheath. In this article, we review the normal appearance of the wrist tendons, discuss relevant anatomy, and give an overview of common pathologic conditions affecting the wrist tendons. Online supplemental material is available for this article. (©)RSNA, 2016.

  19. Comparison of the inhibitory response to tendon and cutaneous afferent stimulation in the human lower limb.

    PubMed

    Rogasch, Nigel C; Burne, John A; Türker, Kemal S

    2012-01-01

    A powerful early inhibition is seen in triceps surae after transcutaneous electrical stimulation of the Achilles tendon [tendon electrical stimulation (TES)]. The aim of the present study was to confirm results from surface electromyogram (SEMG) recordings that the inhibition is not wholly or partly due to stimulation of cutaneous afferents that may lie within range of the tendon electrodes. Because of methodological limitations, SEMG does not reliably identify the time course of inhibitory and excitatory reflex components. This issue was revisited here with an analysis of changes in single motor unit (SMU) firing rate [peristimulus frequencygram (PSF)] and probability [peristimulus time histogram (PSTH)] to reexamine the time course of inhibitory SMU events that follow purely cutaneous (superficial sural) nerve stimulation. Results were then compared with similar data from TES. When compared with the reflex response to TES, sural nerve stimulation resulted in a longer onset latency of the primary inhibition and a weaker effect on SMU firing probability and rate. PSF also revealed that decreased SMU firing rates persisted during the excitation phase in SEMG, suggesting that the initial inhibition was more prolonged than previously reported. In a further study, the transcutaneous SEMG Achilles tendon response was compared with that from direct intratendon stimulation with insulated needle electrodes. This method should attenuate the SEMG response if it is wholly or partly dependent on cutaneous afferents. However, subcutaneous stimulation of the tendon produced similar components in the SEMG, confirming that cutaneous afferents made little or no contribution to the initial inhibition following TES.

  20. Comparison of conventional MRI and MR arthrography in the evaluation of wrist ligament tears: A preliminary experience

    PubMed Central

    Pahwa, Shivani; Srivastava, Deep N; Sharma, Raju; Gamanagatti, Shivanand; Kotwal, Prakash P; Sharma, Vijay

    2014-01-01

    Aims: To compare conventional magnetic resonance imaging (MRI) and direct magnetic resonance (MR) arthrography in the evaluation of triangular fibrocartilage complex (TFCC) and intrinsic wrist ligament tears. Materials and Methods: T1-weighted, fat suppressed (FS) proton density plus T2-weighted (FS PD/T2), 3D multiple-echo data image combination (MEDIC) sequences and direct MR arthrography were performed in 53 patients with wrist pain. Images were evaluated for the presence and location of TFCC, scapholunate ligament (SLL) and lunatotriquetral ligament (LTL) tears, and imaging findings were compared with operative findings in 16 patients who underwent arthroscopy or open surgery (gold standard). Results: Sixteen patients underwent arthroscopy/open surgery: 12 TFCC tears were detected arthroscopically out of which 9 were detected on FS PD/T2 sequence, 10 on MEDIC sequence, and all 12 were detected on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in the detection of TFCC tears were 75%, 83.3%, and 100%, respectively. Out of the eight arthroscopically confirmed SLL tears, three tears were detected on FS PD/T2 sequence, five on MEDIC sequence, and all eight were visualized on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in detecting SLL tears were 37.5%, 62.5%, and 100%, respectively. One arthroscopically confirmed LTL tear was diagnosed on FS PD/T2 sequence, three on MEDIC sequence, and all five arthroscopically confirmed LTL tears were detected with MR arthrography. The sensitivities of PD, MEDIC sequences, and MR arthrography in detecting LTL tears were 20%, 40%, and 100%, respectively. Conclusions: MR arthrography is the most sensitive and specific imaging modality for the evaluation of wrist ligament tears. PMID:25114389

  1. Extrapolating Neoclassical Tearing Mode Physics to ITER -- Physics Basis and Experimental Comparison

    NASA Astrophysics Data System (ADS)

    Buttery, Richard

    2007-11-01

    Neoclassical Tearing Modes (NTMs) represent one of the most serious concerns for baseline and hybrid scenario performance in ITER. Already on present devices they limit attainable β, degrading confinement and causing disruptions. The concern is increased for ITER where stabilising small island and rotation effects are likely to be reduced. In this paper we review the physics basis for NTM scalings, and compare to experimental behaviour, to deduce the key effects and impact on ITER prediction. The principal criteria for NTM onset is dictated by a competition between stabilising small island effects, and the drive from NTM-triggering MHD (eg. sawteeth). Typically the former arise from orbit and transport effects when island sizes are comparable to ion banana widths. This suggests a lowering of NTM β thresholds as ITER-like ρi^*s are approached. In addition, reduced plasma rotation will increase NTM coupling to other instabilities and decrease stabilising effects due to wall and rotation shear. New studies on JET and DIII-D have highlighted this with falls of ˜30% in both m/n=3/2 and 2/1 NTM β thresholds as momentum injection is removed. Indeed, a wide body of work confirms many aspects of the theory, particularly the expected small island effects and ρi^* scalings, while more detailed examinations, for example locally perturbing rotation with error fields, begin to distinguish particular physics mechanisms such as ion polarisation current effects. Thus consideration of the stabilising elements points to a lower metastability threshold for the NTM in ITER. Nevertheless, the triggering mechanisms provide grounds for optimism. For the most serious 2/1 NTM, onset in hybrid, and possibly baseline, scenario appears related to proximity to ideal β limits. Conversely, modes triggered by core MHD may be managed by proven control techniques for the core MHD itself.

  2. Comparison of tendon tensions estimated from two biomechanical models of the thumb.

    PubMed

    Vigouroux, Laurent; Domalain, Mathieu; Berton, Eric

    2009-08-07

    Despite the paramount function of the thumb in daily life, thumb biomechanical models have been little developed and studied. Moreover, only two studies provided quantitative anthropometric data of tendon moment arms. To investigate thumb tendon tensions, biomechanicians and clinicians have to know the performances and the limits of these two data sets. The aim of this study was thus to compare the results of these two models and evaluate their performances in regard to prior electromyographic measurements (EMG). Thumb posture was recorded during the classical key pinch and pulp pinch grips. Various fingertip forces applied at the distal segment were simulated in a range including extension, adduction, flexion, abduction. Input data of thumb postures and fingertip forces were used to compute tendon tensions with both models. Tendon tensions obtained using these two models were then compared and correlated to EMG measurements provided in the literature. The results showed that both models predicted relevant muscle coordination for five of the nine muscles modelled. Opponent and abductor longus muscle coordinations were badly estimated by both models. Each model was sensible to kinematic errors but not in the same proportion. This study pointed out the advantages/limits of the two models to use them more appropriately for clinical and/or research purposes.

  3. The Hug-up Test: A New, Sensitive Diagnostic Test for Supraspinatus Tears

    PubMed Central

    Liu, Yu-Lei; Ao, Ying-Fang; Yan, Hui; Cui, Guo-Qing

    2016-01-01

    Background: The supraspinatus tendon is the most commonly affected tendon in rotator cuff tears. Early detection of a supraspinatus tear using an accurate physical examination is, therefore, important. However, the currently used physical tests for detecting supraspinatus tears are poor diagnostic indicators and involve a wide range of sensitivity and specificity values. Therefore, the aim of this study was to establish a new physical test for the diagnosis of supraspinatus tears and evaluate its accuracy in comparison with conventional tests. Methods: Between November 2012 and January 2014, 200 consecutive patients undergoing shoulder arthroscopy were prospectively evaluated preoperatively. The hug-up test, empty can (EC) test, full can (FC) test, Neer impingement sign, and Hawkins-Kennedy impingement sign were used and compared statistically for their accuracy in terms of supraspinatus tears, with arthroscopic findings as the gold standard. Muscle strength was precisely quantified using an electronic digital tensiometer. Results: The prevalence of supraspinatus tears was 76.5%. The hug-up test demonstrated the highest sensitivity (94.1%), with a low negative likelihood ratio (NLR, 0.08) and comparable specificity (76.6%) compared with the other four tests. The area under the receiver operating characteristic curve for the hug-up test was 0.854, with no statistical difference compared with the EC test (z = 1.438, P = 0.075) or the FC test (z = 1.498, P = 0.067). The hug-up test showed no statistical difference in terms of detecting different tear patterns according to the position (χ2 = 0.578, P = 0.898) and size (Fisher's exact test, P > 0.999) compared with the arthroscopic examination. The interobserver reproducibility of the hug-up test was high, with a kappa coefficient of 0.823. Conclusions: The hug-up test can accurately detect supraspinatus tears with a high sensitivity, comparable specificity, and low NLR compared with the conventional clinical tests and

  4. 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 ...

  5. Measuring Regional Changes in Damaged Tendon

    NASA Astrophysics Data System (ADS)

    Frisch, Catherine Kayt Vincent

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

  6. Classification of ulnar triangular fibrocartilage complex tears. A treatment algorithm for Palmer type IB tears.

    PubMed

    Atzei, A; Luchetti, R; Garagnani, L

    2017-01-01

    The classical definition of 'Palmer Type IB' triangular fibrocartilage complex tear, includes a spectrum of clinical conditions. This review highlights the clinical and arthroscopic criteria that enable us to categorize five classes on a treatment-oriented classification system of triangular fibrocartilage complex peripheral tears. Class 1 lesions represent isolated tears of the distal triangular fibrocartilage complex without distal radio-ulnar joint instability and are amenable to arthroscopic suture. Class 2 tears include rupture of both the distal triangular fibrocartilage complex and proximal attachments of the triangular fibrocartilage complex to the fovea. Class 3 tears constitute isolated ruptures of the proximal attachment of the triangular fibrocartilage complex to the fovea; they are not visible at radio-carpal arthroscopy. Both Class 2 and Class 3 tears are diagnosed with a positive hook test and are typically associated with distal radio-ulnar joint instability. If required, treatment is through reattachment of the distal radio-ulnar ligament insertions to the fovea. Class 4 lesions are irreparable tears due to the size of the defect or to poor tissue quality and, if required, treatment is through distal radio-ulnar ligament reconstruction with tendon graft. Class 5 tears are associated with distal radio-ulnar joint arthritis and can only be treated with salvage procedures. This subdivision of type IB triangular fibrocartilage complex tear provides more insights in the pathomechanics and treatment strategies.

  7. Comparison of the effects of first and second generation silicone hydrogel contact lens wear on tear film osmolarity

    PubMed Central

    Iskeleli, Guzin; Karakoc, Yunus; Ozkok, Ahmet; Arici, Ceyhun; Ozcan, Omer; Ipcioglu, Osman

    2013-01-01

    AIM To compare the effects of first and second generation silicone hydrogel (SiH) contact lens wear on tear film osmolarity. METHODS The healthy subjects who have never used contact lenses before were enrolled in the study. Tear film osmolarity values of 16 eyes (group 1) who wore first generation SiH contact lenses were compared with those of 18 eyes (group 2) who wore second generation SiH contact lenses after three months follow-up. RESULTS Before contact lens wear, tear film osmolarity of groups 1 and 2 were 305.02±49.08 milliosmole (mOsm) and 284.66±30.18mOsm, respectively. After three months of contact lens wear, osmolarity values were found 317.74±60.23mOsm in group 1 and 298.40±37.77mOsm in group 2. Although osmolarity values for both groups of SiH contact lens wear after three months periods were slightly higher than before the contact lens wear, the difference was not statistically significant. CONCLUSION Contact lens wear may cause evaporation from the tear film and can increase tear film osmolarity leading to symptoms of dry eye disease. In the current study, there is a tendency to increase tear film osmolarity for both groups of SiH contact lens wear, but the difference is not statistically significant. PMID:24195046

  8. Blocked Tear Duct

    MedlinePlus

    Blocked tear duct Overview By Mayo Clinic Staff When you have a blocked tear duct, your tears can't drain normally, leaving you ... in the tear drainage system. A blocked tear duct is common in newborns. The condition usually gets ...

  9. 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.

  10. Rotator Cuff Tear Consequent to Glenohumeral Dislocation.

    PubMed

    Gilotra, Mohit N; Christian, Matthew W; Lovering, Richard M

    2016-08-01

    The patient was a 21-year-old collegiate running back who was tackled during a football game and sustained a posterior glenohumeral dislocation. He was referred to an orthopaedist and presented 3 weeks after the injury, and, following examination, further imaging was ordered by the orthopaedist due to rotator cuff weakness. Magnetic resonance imaging showed a complete tear of the supraspinatus and infraspinatus, as well as a posterior Bankart lesion, a subscapularis tear, and a dislocation of the biceps long head tendon into the reverse Hill-Sachs lesion. J Orthop Sports Phys Ther 2016;46(8):708. doi:10.2519/jospt.2016.0413.

  11. Comparison of tear osmolarity and ocular comfort between daily disposable contact lenses: hilafilcon B hydrogel versus narafilcon A silicone hydrogel.

    PubMed

    Sarac, Ozge; Gurdal, Canan; Bostancı-Ceran, Basak; Can, Izzet

    2012-06-01

    The aim of this study was to evaluate tear osmolarity and ocular comfort with two different types of hydrogel daily disposable lenses. The right eyes of 15 first-time contact lens users were included in this prospective study. All eyes wore hilafilcon B silicone hydrogel contact lenses for 8 h (group 1). After 1 week without contact lenses, all eyes wore narafilcon A silicone hydrogel contact lenses for 8 h (group 2). Tear osmolarity measurement was performed before and after 4 and 8 h of each contact lens wear. Ocular comfort was assessed after 4 and 8 h of each contact lens wear. In group 1, the mean baseline, 4- and 8-h tear osmolarity values were 293 ± 10.57, 303.00 ± 10.5 mOsm/L (p = 0.023), and 295.0 ± 1.4 mOsm/L (p > 0.05), respectively. In group 2, the mean baseline, 4- and 8-h tear osmolarity values were 294 ± 13.65, 300.9 ± 11.3 mOsm/L (p = 0.007), and 298.80 ± 7.2 mOsm/L (p > 0.05), respectively. In group 1, the mean comfort score was 7.20 ± 0.45 and 8.60 ± 0.45 at 4 and 8 h, respectively (p = 0.038). In group 2, the mean comfort score significantly decreased from 9.80 ± 0.45 to 7.80 ± 0.84 at 4 h (p = 0.039). Both hydrogel and silicone hydrogel daily disposable contact lenses elevated tear osmolarity during 8 h of contact lens wear. The increase in tear osmolarity with both contact lenses was below the cut-off value for dry eye and was not associated with ocular comfort.

  12. [Fracture toughness of cortical bone in tension, shear, and tear--a comparison of longitudinal and transverse fracture].

    PubMed

    Feng, Z

    1997-09-01

    The fracture toughness at crack initiation was determined for bovine cortical bone under tension (mode I), shear (mode II), and tear (mode III). A total of 130 compact tension specimens, compact shear specimens and triple pantleg specimens were used for the measurement of fracture toughness under tension, shear, and tear, respectively. Multiple-sample compliance method was utilized to measure the critical strain energy release rate (Gc) at the a/W = 0.55 (crack length, a, to specimen width, W, ratio). The critical stress intensity factor (Kc) was also calculated from the critical loading (PQ) of the specimens at the a/W = 0.55. The effect of the anisotropy of bone on its resistance to crack initiation under shear and tear loading was investigated as well. The fracture toughness of bone with precrack orientations parallel(designed as longitudinal fracture) to and that with precrack orientations normal (designed as transverse fracture) to the longitudinal axis of bone were compared. In longitudinal fracture, the critical strain energy release rates(Gc) of cortical bone under tension, shear, and tear were 644 +/- 102, 2430 +/- 836, and 1723 +/- 486 N/m, respectively. In transverse fracture, the critical strain energy release rates(Gc) of cortical bone under tesion, shear, and tear were 1374 +/- 183, 4710 +/- 1284, and 4016 +/- 948 N/m, respectively. An analysis of variance demonstrated that the crack initiation fracture toughness of bone under shear and tear loading is significantly greater than that under tensile loading in both longitudinal and transverse fracture. Our results also suggest that cortical bone has been "designed" to prevent crack initiation in transverse fracture under tension, shear, and tesar.

  13. 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

  14. 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 ...

  15. Tear Film Mucins: Front Line Defenders of the Ocular Surface; Comparison with Airway and Gastrointestinal Tract Mucins

    PubMed Central

    Hodges, Robin R.; Dartt, Darlene A.

    2014-01-01

    The ocular surface including the cornea and conjunctiva and its overlying tear film are the first tissues of the eye to interact with the external environment. The tear film is complex containing multiple layers secreted by different glands and tissues. Each layer contains specific molecules and proteins that not only maintain the health of the cells on the ocular surface by providing nourishment and removal of waste products but also protect these cells from environment. A major protective mechanism that the corneal and conjunctival cells have developed is secretion of the innermost layer of the tear film, the mucous layer. Both the cornea and conjunctiva express membrane spanning mucins, whereas the conjunctiva also produces soluble mucins. The mucins present in the tear film serve to maintain the hydration of the ocular surface and to provide lubrication and anti-adhesive properties between the cells of the ocular surface and conjunctiva during the blink. A third function is to contribute to the epithelial barrier to prevent pathogens from binding to the ocular surface. This review will focus on the different types of mucins produced by the corneal and conjunctival epithelia. Also included in this review will be a presentation of the structure of mucins, regulation of mucin production, role of mucins in ocular surface diseases, and the differences in mucin production by the ocular surface, airways and gastrointestinal tract. PMID:23954166

  16. Comma Sign–Directed Repair of Anterosuperior Rotator Cuff Tears

    PubMed Central

    Dilisio, Matthew F.; Neyton, Lionel

    2014-01-01

    The comma sign was described as an arthroscopic landmark to identify the torn subscapularis stump to mobilize and repair the tendon in anterosuperior rotator cuff tears. It was hypothesized that it is composed of the humeral attachments of the superior glenohumeral and coracohumeral ligaments. This arthroscopic finding has since become accepted orthopaedic nomenclature pathognomonic for subscapularis tears and a key component of subscapularis tear classification. We propose an alternative theory of the pathoanatomy of the comma sign in anterosuperior rotator cuff tears and present the technique of comma sign–directed repairs of combined subscapularis and supraspinatus lesions. After appropriate releases, tendon-to-tendon repair of the distal-superior aspect of the comma sign to the upper border of the remnant subscapularis results in anatomic re-creation of the intra-articular portion of the torn subscapularis with concomitant reduction of the anterior leading edge of the supraspinatus and reconstitution of the rotator cable complex. A tension-free, single-anchor subscapularis repair is then performed to secure the tendon to the lesser tuberosity. After subscapularis repair, the supraspinatus that was previously retracted to the glenoid rim takes the appearance of a crescent-type tear that is easily approximated to its anatomic insertion. PMID:25685676

  17. No prosthetic management of massive and irreparable rotator cuff tears

    PubMed Central

    Garofalo, Raffaele; Cesari, Eugenio

    2014-01-01

    A massive rotator cuff tear is not necessarily irreparable. Number of tendons involved, muscle-tendon unit quality, and decreased acromionhumeral distance (AHD) are as important as tear size in determining reparability of lesion. Massive and irreparable rotator cuff tears cannot be anatomically repaired to the bone and are a common source of pain and disability even in middle-aged patients. In these patients when conservative management has failed, it is possible to perform different surgical techniques. A functional repair can help to restore the horizontal force couple of the cuff on the humeral head and to increase the AHD. Debridement of irreparable tears and biceps tenotomy or tenodesis can have a role in low functional demand patients but results deteriorate over time. Recently, several commercially available tissue-engineered biological and synthetic scaffolds have been developed to augment rotator cuff repairs. The aim is to provide a mechanical improvement in case of poor quality tissue at time zero and give a support to have a better cuff healing. In selected cases, the scaffold can be used also to bridge tendon defect. Patients who not have pseudoparalysis, cuff tear arthropathy and with intact deltoid function can benefit from tendon transfers with satisfactory outcomes. These different procedures should be chosen for each patient with selected criteria and after a satisfactory explanation about the really possible expectation after surgery. PMID:27582930

  18. Aspect ratio effects on neoclassical tearing modes from comparison between DIII-D and National Spherical Torus Experiment

    NASA Astrophysics Data System (ADS)

    La Haye, R. J.; Buttery, R. J.; Gerhardt, S. P.; Sabbagh, S. A.; Brennan, D. P.

    2012-06-01

    Neoclassical tearing mode islands are sustained by helically perturbed bootstrap currents arising at finite beta from toroidal effects that trap a fraction of the particles in non-circulating orbits. DIII-D and NSTX are here operated with similar shape and cross-sectional area but almost a factor of two difference in inverse aspect ratio a /R. In these experiments, destabilized n =1 tearing modes were self-stabilized (reached the "marginal point") by reducing neutral-beam power and thus beta. The measure of the marginal island gives information on the small-island stabilizing physics that in part (with seeding) governs onset. The marginal island width on NSTX is found to be about three times the ion banana width and agrees with that measured in DIII-D, except for DIII-D modes closer to the magnetic axis, which are about two times the ion banana width. There is a balance of the helically perturbed bootstrap term with small island effects with the sum of the classical and curvature terms in the modified Rutherford equation for tearing-mode stability at the experimental marginal point. Empirical evaluation of this sum indicates that while the stabilizing effect of the curvature term is negligible in DIII-D, it is important in NSTX. The mode temporal behavior from the start of neutral-beam injection reduction also suggests that NSTX operates closer to marginal classical tearing stability; this explains why there is little hysteresis in beta between mode onset, saturation, and self-stabilization (while DIII-D has large hysteresis in beta). NIMROD code module component calculations based on DIII-D and NSTX reconstructed experimental equilibria are used to diagnose and confirm the relative importance of the stabilizing curvature effect, an advantage for low aspect ratio; the relatively greater curvature effect makes for less susceptibility to NTM onset even if the classical tearing stability index is near marginal.

  19. 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.

  20. Artificial tears potpourri: a literature review

    PubMed Central

    Moshirfar, Majid; Pierson, Kasey; Hanamaikai, Kamalani; Santiago-Caban, Luis; Muthappan, Valliammai; Passi, Samuel F

    2014-01-01

    Numerous brands and types of artificial tears are available on the market for the treatment of dysfunctional tear syndrome. Past literature has focused on comparing the components of these products on patient’s clinical improvement. The wide array of products on the market presents challenges to both clinicians and patients when trying to choose between available tear replacement therapies. Different formulations affect patients based on etiology and severity of disease. In order to provide an unbiased comparison between available tear replacement therapies, we conducted a literature review of existing studies and National Institutes of Health clinical trials on commercially available, brand name artificial tears. Outcomes evaluated in each study, as well as the percent of patients showing clinical and symptomatic improvement, were analyzed. Fifty-one studies evaluating different brands of artificial tears, and their efficacy were identified. Out of the 51 studies, 18 were comparison studies testing brand name artificial tears directly against each other. Nearly all formulations of artificial tears provided significant benefit to patients with dysfunctional tear syndrome, but some proved superior to others. From the study data, a recommended treatment flowchart was derived. PMID:25114502

  1. Distal biceps tendon injuries: diagnosis and management.

    PubMed

    Ramsey, M L

    1999-01-01

    Rupture of the distal biceps tendon occurs most commonly in the dominant extremity of men between 40 and 60 years of age when an unexpected extension force is applied to the flexed arm. Although previously thought to be an uncommon injury, distal biceps tendon ruptures are being reported with increasing frequency. The rupture typically occurs at the tendon insertion into the radial tuberosity in an area of preexisting tendon degeneration. The diagnosis is made on the basis of a history of a painful, tearing sensation in the antecubital region. Physical examination demonstrates a palpable and visible deformity of the distal biceps muscle belly with weakness in flexion and supination. The ability to palpate the tendon in the antecubital fossa may indicate partial tearing of the biceps tendon. Plain radiographs may show hypertrophic bone formation at the radial tuberosity. Magnetic resonance imaging is generally not required to diagnose a complete rupture but may be useful in the case of a partial rupture. Early surgical reattachment to the radial tuberosity is recommended for optimal results. A modified two-incision technique is the most widely used method of repair, but anterior single-incision techniques may be equally effective provided the radial nerve is protected. The patient with a chronic rupture may benefit from surgical reattachment, but proximal retraction and scarring of the muscle belly can make tendon mobilization difficult, and inadequate length of the distal biceps tendon may necessitate tendon augmentation. Postoperative rehabilitation must emphasize protected return of motion for the first 8 weeks after repair. Formal strengthening may begin as early as 8 weeks, with a return to unrestricted activities, including lifting, by 5 months.

  2. Comparison of elasticity of human tendon and aponeurosis in knee extensors and ankle plantar flexors in vivo.

    PubMed

    Kubo, Keitaro; Kanehisa, Hiroaki; Fukunaga, Tetsuo

    2005-05-01

    The purposes of this study were to compare the elasticity of tendon and aponeurosis in human knee extensors and ankle plantar flexors in vivo and to examine whether the maximal strain of tendon was correlated to that of aponeurosis. The elongation of tendon and aponeurosis during isometric knee extension (n = 23) and ankle plantar flexion (n = 22), respectively, were determined using a real-time ultrasonic apparatus, while the participants performed ramp isometric contractions up to voluntary maximum. To calculate the strain values from the measured elongation, we measured the respective length of tendon and aponeurosis. For the knee extensors, the maximal strain of aponeurosis (12.1 +/- 2.8 %) was significantly greater than that of the patella tendon (8.3 +/- 2.4 %), p < 0.001. On the contrary, the maximal strain of Achilles tendon (5.9 +/- 1.4 %) was significantly greater than that of aponeurosis in ankle plantar flexors (2.7 +/- 1.4 %), p < 0.001. Furthermore, for both knee extensors and ankle plantar flexors there was no significant correlation between maximal strain of tendon and aponeurosis. These results would be important for understanding the different roles of tendon and aponeurosis during human movements and for more accurate muscle modeling.

  3. Management of massive and irreparable rotator cuff tears.

    PubMed

    Neri, Brian R; Chan, Keith W; Kwon, Young W

    2009-01-01

    Massive rotator cuff tears pose a distinct clinical challenge for the orthopaedist. In this review, we will discuss the classification, diagnosis, and evaluation of massive rotator cuff tears before discussing various treatment options for this problem. Nonoperative treatment has had inconsistent results and proven unsuccessful for chronic symptoms while operative treatment including debridement and partial and complete repairs have had varying degrees of success. For rotator cuff tears that are deemed irreparable, treatment options are limited. The use of tendon transfers in younger patients to reconstruct rotator cuff function and restore shoulder kinematics can be useful in salvaging this difficult problem.

  4. 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 ...

  5. Rotator cuff tears: An evidence based approach

    PubMed Central

    Sambandam, Senthil Nathan; Khanna, Vishesh; Gul, Arif; Mounasamy, Varatharaj

    2015-01-01

    Lesions of the rotator cuff (RC) are a common occurrence affecting millions of people across all parts of the globe. RC tears are also rampantly prevalent with an age-dependent increase in numbers. Other associated factors include a history of trauma, limb dominance, contralateral shoulder, smoking-status, hypercholesterolemia, posture and occupational dispositions. The challenge lies in early diagnosis since a high proportion of patients are asymptomatic. Pain and decreasing shoulder power and function should alert the heedful practitioner in recognizing promptly the onset or aggravation of existing RC tears. Partial-thickness tears (PTT) can be bursal-sided or articular-sided tears. Over the course of time, PTT enlarge and propagate into full-thickness tears (FTT) and develop distinct chronic pathological changes due to muscle retraction, fatty infiltration and muscle atrophy. These lead to a reduction in tendon elasticity and viability. Eventually, the glenohumeral joint experiences a series of degenerative alterations - cuff tear arthropathy. To avert this, a vigilant clinician must utilize and corroborate clinical skill and radiological findings to identify tear progression. Modern radio-diagnostic means of ultrasonography and magnetic resonance imaging provide excellent visualization of structural details and are crucial in determining further course of action for these patients. Physical therapy along with activity modifications, anti-inflammatory and analgesic medications form the pillars of nonoperative treatment. Elderly patients with minimal functional demands can be managed conservatively and reassessed at frequent intervals. Regular monitoring helps in isolating patients who require surgical interventions. Early surgery should be considered in younger, active and symptomatic, healthy patients. In addition to being cost-effective, this helps in providing a functional shoulder with a stable cuff. An easily reproducible technique of maximal strength and

  6. Comparison of superficial digital flexor tendon loading on asphalt and sand in horses at the walk and trot.

    PubMed

    Crevier-Denoix, N; Ravary-Plumioën, B; Vergari, C; Camus, M; Holden-Douilly, L; Falala, S; Jerbi, H; Desquilbet, L; Chateau, H; Denoix, J-M; Pourcelot, P

    2013-12-01

    The incidence of superficial digital flexor tendon (SDFT) injuries is one of the highest of all equine musculoskeletal conditions. Horses with SDFT injuries commonly show no improvement of lameness on soft ground, unlike those suffering from distal bone or joint lesions. The aim of this study was to compare the SDFT loading in five horses at the walk and trot on asphalt and sand using a non-invasive ultrasonic tendon force measurement device. Three horses were equipped with the ultrasonic device, whereas the other two horses were equipped with the ultrasonic device and a dynamometric horseshoe (DHS); the DHS was used to calibrate the measured values of tendon speed of sound (SOS) converted to tendon force, while a previously established ground reaction force pattern was used to calibrate SOS measurements for the other three horses. Although the horses tended to be slower on S, maximal tendon force was higher on sand than on asphalt at the trot (+6%); there was no significant difference between the two surfaces at the walk. The duration of tendon loading was longer on S (+5%) and the area under the tendon force-time curve was larger on S (+10%) at both walk and trot. SDFT loading is significantly affected by the ground surface and the observed increase in SDFT loading on sand compared with asphalt is consistent with clinical observations in horses with SDFT injuries.

  7. Meniscal tears: comparison of the conventional spin-echo and fast spin-echo techniques through image processing

    PubMed Central

    2014-01-01

    Background Conventional spin-echo (PD-CSE) and fast spin-echo (PD-FSE) techniques are frequently used to detect meniscal tears. However, the time delay for imaging with PD-CSE has resulted in its replacement with faster techniques, such as proton density fast spin-echo (PD-FSE), which has become a frequent tool at most diagnostic centres. Qualitative analysis shows that the PD-CSE technique is more sensitive, but other authors have not found significant differences between the aforementioned techniques. Therefore, we performed a quantitative analysis in this study that aims to measure differences in the quality of the images obtained with both techniques. Methods We compared the PD-CSE and PD-FSE techniques by quantitatively analysing the obtained proton density images: the area shown, as well as the brightness and lesion contrast of the obtained image. A set of 100 images from 50 patients thought to contain meniscal tears of the knee were selected. These 100 images were obtained from all individuals using both the PD-CSE and PD-FSE techniques. The images were processed using software developed in Delphi. In addition to these quantifications, three physicians, who are specialists in radiology and capable of analysing magnetic resonance (MR) images of the musculoskeletal system, qualitatively analysed the diagnostic sensitivity of both techniques. Results On average, samples obtained via the PD-CSE technique contained 22% more pixels in the lesion area. The contrast differed by 28%, and the brightness differed by 31%. The two techniques were correlated using Student’s t-test, which showed a statistically significant difference. The specialists detected meniscal tears in 30 of the images obtained via the PD-CSE technique, while only 72% of these cases were detected via the PD-FSE technique. Conclusions The PD-CSE technique was shown to be superior to PD-FSE for all of the evaluated properties, making its selection preferable. PMID:24673813

  8. Tibial Fixation of Anterior Cruciate Ligament Allograft Tendons. Comparison of 1-, 2-, and 4-Stranded Constructs

    DTIC Science & Technology

    2009-01-01

    Provencher Daniel K. Park, Harold A. Fogel, Sanjeev Bhatia, Bernard R. Bach , Jr, Aman Gupta, Elizabeth F. Shewman, Vincent Tibial Fixation of Anterior...Harold A. Fogel,* BA, Sanjeev Bhatia,* MD, Bernard R. Bach Jr,* MD, Aman Gupta,* Elizabeth F. Shewman,* PhD, Vincent Wang,* PhD, Nikhil Verma,* MD...knee laxity: a comparison of five arthrometers. Am J Sports Med. 1992;20:135-140. 3. Bach BR Jr. Revision anterior cruciate ligament surgery

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

    PubMed Central

    Young, Mark

    2012-01-01

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

  10. Streaming tearing mode

    NASA Technical Reports Server (NTRS)

    Shigeta, M.; Sato, T.; Dasgupta, B.

    1985-01-01

    The magnetohydrodynamic stability of streaming tearing mode is investigated numerically. A bulk plasma flow parallel to the antiparallel magnetic field lines and localized in the neutral sheet excites a streaming tearing mode more strongly than the usual tearing mode, particularly for the wavelength of the order of the neutral sheet width (or smaller), which is stable for the usual tearing mode. Interestingly, examination of the eigenfunctions of the velocity perturbation and the magnetic field perturbation indicates that the streaming tearing mode carries more energy in terms of the kinetic energy rather than the magnetic energy. This suggests that the streaming tearing mode instability can be a more feasible mechanism of plasma acceleration than the usual tearing mode instability.

  11. Comparison of Roll Stitch Technique and Core Suture Technique for Extensor Tendon Repair at the Metacarpophalangeal Joint level

    PubMed Central

    Namazi, Hamid; Mozaffarian, Kamran; Golmakani, Mohammad Reza

    2016-01-01

    Background: Proper suturing technique is needed to ensure good outcome in extensor tendon surgery. Different techniques have been reported for the repair of extensor tendon injuries at the level of the metacarpophalangeal joint (MCPJ). These reports were in vitro studies on cadaver models. Repair techniques must be clinically tested, to determine results. Objectives: The purpose of this in vivo study was to compare results of extensor tendon repair, using roll stitch and core suture techniques. Patients and Methods: Forty two fingers, in 38 patients (aged 15- 45 years), with simple complete extensor tendon injuries in the MCPJ area, were identified and operated by a single surgeon. The patients were divided into two groups, according to the technique used for tendon repair. The first group consisted of 21 digits, in 19 patients, who were repaired with roll stitch technique, while the second group consisted of 21 digits, in 19 patients, who were repaired with core suture technique. The same splint and rehabilitation regimen (early passive range of motion) were given to all patients. The splints were removed at 6 weeks after surgery and range of motion of the operated fingers was measured and compared to uninjured hands, after 12 weeks. Results: Five patients were lost to follow up or excluded from the study. There was no rupture of the repaired tendons in the groups. There was no statistically significant difference in mean MCPJ flexion, proximal interphalangeal joint (PIPJ) flexion, distal interphalangeal joint (DIPJ) flexion and total range of motion of the fingers, between the two groups. However, extension lag was significantly more common in the second group (11 of 19 digits) compared the first group (four of 17 digits). Conclusions: Roll stitch technique had superior outcome compared to the modified Kessler technique, when performed in the MCPJ area. Level of evidence: Therapeutic (Level III) PMID:27218053

  12. A comparison of functional outcomes in patients undergoing revision arthroscopic repair of massive rotator cuff tears with and without arthroscopic suprascapular nerve release

    PubMed Central

    Savoie, Felix H; Zunkiewicz, Mark; Field, Larry D; Replogle, William H; O’Brien, Michael J

    2016-01-01

    Purpose This study was designed to compare functional outcomes in patients undergoing revision repair of massive rotator cuff tears (retracted medial to the glenoid) with Goutallier Grade 4 atrophy and concomitant release of the suprascapular nerve to a similar group of patients with Grade 3 atrophy undergoing revision rotator cuff repair (RTCR) without nerve release. We hypothesized that patients undergoing nerve release would have more favorable functional outcomes as measured by the Modified University of California at Los Angeles shoulder rating scale (UCLA). Patients and methods Twenty-two patients underwent revision repair of massive rotator cuff tears with release of the suprascapular nerve at the suprascapular notch. We compared total preoperative, postoperative, and change in UCLA score in these patients to a similar group of 22 patients undergoing revision RTCR without suprascapular nerve release. Additionally, UCLA subscores between the two groups were compared preoperatively and at final follow-up. Results The average preoperative UCLA score in the nerve-release group was 7.91, and final follow-up average was 27.86; average 3.05 grades of strength were recovered. In the comparison group, average preoperative UCLA score was 11.77, and final follow-up average was 29.09; average 1.32 grades of strength were recovered. The average preoperative UCLA score was significantly worse in the nerve-release group (P=0.007). The average postoperative UCLA score was not significantly different (P=0.590) between the groups, indicating a better improvement in the nerve-release group with significantly greater improvement in active forward flexion, strength, and pain relief. Conclusion Patients who underwent concomitant release of the suprascapular nerve during revision RTCR had greater overall improvement as noted in pain relief, active forward flexion, and strength, than a comparable group without nerve release. PMID:27799834

  13. Bilateral Congenital Agenesis of the Long Head of the Biceps Tendon: The Beginning

    PubMed Central

    Rego Costa, Francisco; Esteves, Cátia; Melão, Lina

    2016-01-01

    The biceps brachii muscle is prone to variants but absence of the long head of the biceps (LHB) tendon is an exceptionally rare anomaly. This report concerns the fourth case of bilateral congenital absence of the LHB tendon and presents the ultrasonography (US) and magnetic resonance (MR) findings. Our case has the peculiarity of being the first in which bilateral LHB tendon agenesis is not associated with rotator cuff or labral tears. PMID:26904345

  14. Comparison of Morphology, Orientation, and Migration of Tendon Derived Fibroblasts and Bone Marrow Stromal Cells on Electrochemically Aligned Collagen Constructs

    PubMed Central

    Gurkan, Umut Atakan; Cheng, Xingguo; Kishore, Vipuil; Uquillas, Jorge Alfredo; Akkus, Ozan

    2010-01-01

    There are approximately 33 million injuries involving musculoskeletal tissues (including tendons and ligaments) every year in the United States. In certain cases the tendons and ligaments are damaged irreversibly and require replacements that possess the natural functional properties of these tissues. As a biomaterial, collagen has been a key ingredient in tissue engineering scaffolds. The application range of collagen in tissue engineering would be greatly broadened if the assembly process could be better controlled to facilitate the synthesis of dense, oriented tissue-like constructs. An electrochemical method has recently been developed in our laboratory to form highly oriented and densely packed collagen bundles with mechanical strength approaching that of tendons. However, there is limited information whether this electrochemically aligned collagen bundle (ELAC) presents advantages over randomly oriented bundles in terms of cell response. Therefore, the current study aimed to assess the biocompatibility of the collagen bundles in vitro, and compare tendon derived fibroblasts (TDFs) and bone marrow stromal cells (MSCs) in terms of their ability to populate and migrate on the single and braided ELAC bundles. The results indicated that the ELAC was not cytotoxic; both cell types were able to populate and migrate on the ELAC bundles more efficiently than that observed for random collagen bundles. The braided ELAC constructs were efficiently populated by both TDFs and MSCs in vitro. Therefore, both TDFs and MSCs can be used with the ELAC bundles for tissue engineering purposes. PMID:20694974

  15. 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 ...

  16. Open subpectoral biceps tenodesis: reliable treatment for all biceps tendon pathology.

    PubMed

    Kane, Patrick; Hsaio, Philip; Tucker, Bradford; Freedman, Kevin B

    2015-01-01

    Long head of the biceps (LHB) tendon pathology is a common cause of pain in the shoulder. Pathology encountered includes biceps tendon tears and tendonitis, biceps anchor or superior labral tears, and biceps subluxation or instability. Current surgical treatment options for LHB disorders include tenotomy and tenodesis. Tenodesis prevents cosmetic deformity and biceps cramping with activity. Open subpectoral tenodesis anatomically restores the length-tension relationship of the biceps muscle and removes all diseased biceps from the bicipital groove. The authors present their technique of open subpectoral tenodesis, which demonstrates a high success rate with consistent pain relief and dependable fixation.

  17. Comparison of the Anti-Inflammatory Effects of Artificial Tears in a Rat Model of Corneal Scraping

    PubMed Central

    Daull, Philippe; Feraille, Laurence; Elena, Pierre-Paul

    2016-01-01

    Abstract Purpose: Artificial tears (ATs) are used routinely to alleviate the symptoms of mild to moderate dry eye. Preservative-free cationic emulsions (eg, Cationorm®) are an innovative approach for the management of signs and symptoms of dry eye. The aim of the present exploratory experiment was to evaluate the efficacy of this cetalkonium chloride (CKC)-containing cationic emulsion on debrided cornea and to characterize its effects on scraping-induced inflammation. Methods: Four ATs were assessed in a rat model of corneal scraping. The upper part of the corneal epithelium was scraped before a 5-day treatment, followed by clinical evaluations and fluorescein staining to evaluate cornea recovery. The anti-inflammatory efficacy of the ATs was assessed in vivo and in vitro. Results: In vivo confocal microscopy (IVCM) revealed a trend toward better corneal clinical signs (lower IVCM scores) for the animals treated with the unpreserved ATs. Benzalkonium chloride treatment decreased goblet cell count by 37.5%. While the soft-preserved Systane Balance® and Optive® and the preservative-free Vismed® had no effect on the goblet cell count, Cationorm increased this count by almost 40%. Interestingly, inflammatory cell infiltration in the stroma was at its lowest following treatment with the preservative-free Cationorm. Cationorm is also the only AT decreasing IL6- and IL8-stimulated secretion by 59% and 74%, respectively. Conclusion: By restoring an adequately hydrated ocular surface environment, the different ATs promote corneal epithelium healing. These data position Cationorm as a promising AT for the management of signs and symptoms of dry eye in patients with mild to moderate dry eye disease presenting chronic subclinical levels of ocular inflammation. PMID:26751507

  18. Torn human rotator cuff tendons have reduced collagen thermal properties on differential scanning calorimetry.

    PubMed

    Chaudhury, Salma; Holland, Christopher; Porter, David; Tirlapur, Uday K; Vollrath, Fritz; Carr, Andrew J

    2011-12-01

    The cause of the high failure rates often observed following rotator cuff tendon repairs, particularly massive tears, is not fully understood. Collagen structural changes have been shown to alter tendon thermal and mechanical properties. This study aimed to form a quantitative rather than qualitative assessment, of whether differences in collagen structure and integrity existed between small biopsies of normal, small, and massive rotator cuff tears using differential scanning calorimetry. Thermal properties were measured for 28 human biopsies taken intra-operatively from normal, small, and massive rotator cuff tendon tears in this powered study. Denaturation temperatures are represented by T(onset) (°C) and T(peak) (°C). The T(onset) is proposed to represent water-amide hydrogen bond breakage and resulting protein backbone mobility. T(peak) reportedly corresponds to the temperature at which the majority of proteins fall out of solution. Denaturation enthalpy (ΔH) should correlate with the amount of triple helical structure that is denatured. Fluorescence and confocal microscopy allowed quantitative validation. Small and massive rotator cuff tears had significantly higher T(onset), T(peak), and ΔH compared to controls. Polarized light microscopy of torn tendons confirmed greater collagen structural disruption compared to controls. These novel findings suggest greater quantifiable collagen structural disruption in rotator cuff tears, compared to controls. This study offers insight into possible mechanisms for the reduced strength of torn tendons and may explain why repaired tendons fail to heal.

  19. Tears of the fascia cruris demonstrate characteristic sonographic features: a case series analysis

    PubMed Central

    Morton, Sarah; Chan, Otto; Webborn, Nick; Pritchard, Melanie; Morrissey, Dylan

    2015-01-01

    Summary Background fascia cruris (FC) tears have recently been recognised in the literature, although little is known about their characteristic ultrasound findings. The aim was to describe the echo-graphic features of FC tears in order to improve recognition and diagnosis. Methods the ultrasound reports and images of >600 patients attending a specialist musculoskeletal clinic for Achilles tendon ultrasound scans between October 2010–May 2014 were reviewed. Any patient diagnosed with a FC tear had a structured data set extracted. All ultrasound images were performed by one consultant radiologist. Bilateral Achilles images were available for analysis. Results sixteen patients from >600 subjects were diagnosed with a FC tear. Fourteen subjects were male and two female (mean age 37.8; range 23–61), with seven elite level sports men. Nine tears were right sided and seven left, with eight situated laterally and seven medially. Seven of the tears were situated in the musculotendinous junction. Symptomatic Achilles tendinopathy co-existed in ten of sixteen subjects (average transverse diameter of Achilles tendon = 7.1±2.0 mm). Conclusion FC tears should be considered in the differential diagnoses for Achillodynia, diagnosed using their characteristic ultrasound findings, with a hypoechoic area at the medial or lateral attachment to the Achilles tendon in the transverse plane. PMID:26958540

  20. Non-Operative Management of Rotator Cuff Tears

    PubMed Central

    Petri, M.; Ettinger, M.; Brand, S.; Stuebig, T.; Krettek, C.; Omar, M.

    2016-01-01

    Background: The role of nonoperative management for rotator cuff tears remains a matter of debate. Clinical results reported in the literature mainly consist of level IV studies, oftentimes combining a mixed bag of tear sizes and configurations, and are contradictory to some extent. Methods: A selective literature search was performed and personal surgical experiences are reported. Results: Most studies show an overall success rate of around 75% for nonoperative treatment. However, the majority of studies also present a progression of tear size and fatty muscle infiltration over time, with however debatable clinical relevance for the patient. Suggested factors associated with progression of a rotator cuff tear are an age of 60 years or older, full-thickness tears, and fatty infiltration of the rotator cuff muscles at the time of initial diagnosis. Conclusion: Non-operative management is indicated for patients with lower functional demands and moderate symptoms, and/or of course for those refusing to have surgery. Close routinely monitoring regarding development of tear size should be performed, especially in patients that remain symptomatic during nonoperative treatment. To ensure judicious patient counseling, it has to be taken into account that 1) tears that are initially graded as reparable may become irreparable over time, and 2) results after secondary surgical therapy after failed nonoperative treatment are usually reported to be inferior to those who underwent primary tendon repair. PMID:27708737

  1. Sensitivity of physical examination versus arthroscopy in diagnosing subscapularis tendon injury.

    PubMed

    Faruqui, Sami; Wijdicks, Coen; Foad, Abdullah

    2014-01-01

    The purpose of this study was to examine the accuracy of physical examination in the detection of subscapularis tendon tears and compare it with the gold standard of arthroscopy to determine whether clinical examination can reliably predict the presence of subscapularis tendon tears. This was a retrospective analysis of 52 patients (52 shoulders) who underwent arthroscopic subscapularis tendon repairs between September 2008 and April 2012. Positive findings on any combination of the belly press, lift-off, and bear hug tests constituted a positive physical examination result. There was a positive finding on physical examination in 42 of 52 patients. The sensitivity of the physical examination as a whole was 81%. The literature has shown that the belly press, bear hug, and lift-off tests are specific to the subscapularis tendon. To the authors’ knowledge, this is the first study to evaluate the sensitivity of these 3 separate clinical tests as a composite. Knowledge regarding the sensitivity of the subscapularis-specific physical examination as a composite can lead practitioners to implement all 3 components, even when 1 test has a negative finding, thus promoting a more thorough physical examination. Because unrepaired subscapularis tendon tears can result in poor outcomes in the repair of other rotator cuff tendons, a complete physical examination would be beneficial to patients with shoulder pathology. The authors conclude that physical examination, when performed consistently by an experienced practitioner, can reliably predict the presence of subscapularis tendon tears.

  2. A new tear pattern of the rotator cuff and its treatment: Fosbury flop tears

    PubMed Central

    Lädermann, Alexandre; Denard, Patrick J.; Kolo, Frank C.

    2015-01-01

    Purpose: The purpose of this report is to describe a new full-thickness tear pattern of the posterosuperior rotator cuff with reversal healing. We describe the specific radiologic signs associated with this tear pattern and the arthroscopic rotator cuff repair technique. Materials and Methods: A prospective radiologic and clinical study collected all patients with a magnetic resonance imaging arthrogram that underwent an arthroscopic rotator cuff repair over a 1 year period. Results: Among 97 patients, five demonstrated a tear of the posterosuperior rotator cuff with reversal healing. Characteristic radiographic findings included a thicker tendon than normal, the presence of a stump and accumulation of liquid in the superior-medial part of the subacromial bursa, and adhesions between the supraspinatus tendon and the wall of the subacromial bursa. Conclusion: Avulsion of the posterosuperior rotator cuff with reversal healing on its bursal-side is a less common condition. This type of lesion and distinct radiographic signs that can be recognized to facilitate anatomic repair of the rotator cuff. Level of evidence: Level IV. PMID:25709239

  3. A pilot study to assess Fatty infiltration of the supraspinatus in patients with rotator cuff tears: comparison with magnetic resonance imaging.

    PubMed

    Watanabe, Tsuneo; Terabayashi, Nobuo; Fukuoka, Daisuke; Murakami, Hiroki; Ito, Hiroyasu; Matsuoka, Toshio; Seishima, Mitsuru

    2015-06-01

    The aim of this study was to quantitatively assess the echo intensity of the supraspinatus muscle and compare magnetic resonance imaging and ultrasound findings for 27 patients (12 women, 15 men, 65.8 ± 11.5 y). Tear size and fatty infiltration were determined by magnetic resonance imaging; five stages were assigned based on Goutallier's classification. Gray-scale histogram analysis was used for ultrasound assessment, which was performed in both subcutaneous fat and supraspinatus muscle in three different regions; the echo intensity ratio was the ratio of echo intensity in subcutaneous fat to that in the supraspinatus muscle. Sonograms of 27 shoulders revealed 3 shoulders with a partial tear, and 4 with a small tear, 6 with a medium tear, 6 with a large tear and 4 with a massive tear; 4 shoulders had no tear. Supraspinatus muscle echo intensity and echo intensity ratio were significantly lower in the stage 0 and 1 than in stages 2-4. Our study suggests that ultrasound can quantitatively and objectively assess fatty infiltration in the rotator cuff muscle.

  4. Recent Scientific Advances Towards the Development of Tendon Healing Strategies

    PubMed Central

    Sayegh, Eli T.; Sandy, John D.; Virk, Mandeep S.; Romeo, Anthony A.; Wysocki, Robert W.; Galante, Jorge O.; Trella, Katie J.; Plaas, Anna; Wang, Vincent M.

    2015-01-01

    There exists a range of surgical and non-surgical approaches to the treatment of both acute and chronic tendon injuries. Despite surgical advances in the management of acute tears and increasing treatment options for tendinopathies, strategies frequently are unsuccessful, due to impaired mechanical properties of the treated tendon and/or a deficiency in progenitor cell activities. Hence, there is an urgent need for effective therapeutic strategies to augment intrinsic and/or surgical repair. Such approaches can benefit both tendinopathies and tendon tears which, due to their severity, appear to be irreversible or irreparable. Biologic therapies include the utilization of scaffolds as well as gene, growth factor, and cell delivery. These treatment modalities aim to provide mechanical durability or augment the biologic healing potential of the repaired tissue. Here, we review the emerging concepts and scientific evidence which provide a rationale for tissue engineering and regeneration strategies as well as discuss the clinical translation of recent innovations. PMID:26753125

  5. 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

  6. Antimicrobial Compounds in Tears

    PubMed Central

    McDermott, Alison M.

    2013-01-01

    The tear film coats the cornea and conjunctiva and serves several important functions. It provides lubrication, prevents drying of the ocular surface epithelia, helps provide a smooth surface for refracting light, supplies oxygen and is an important component of the innate defense system of the eye providing protection against a range of potential pathogens. This review describes both classic antimicrobial compounds found in tears such as lysozyme and some more recently identified such as members of the cationic antimicrobial peptide family and surfactant protein-D as well as potential new candidate molecules that may contribute to antimicrobial protection. As is readily evident from the literature review herein, tears, like all mucosal fluids, contain a plethora of molecules with known antimicrobial effects. That all of these are active in vivo is debatable as many are present in low concentrations, may be influenced by other tear components such as the ionic environment, and antimicrobial action may be only one of several activities ascribed to the molecule. However, there are many studies showing synergistic/additive interactions between several of the tear antimicrobials and it is highly likely that cooperativity between molecules is the primary way tears are able to afford significant antimicrobial protection to the ocular surface in vivo. In addition to effects on pathogen growth and survival some tear components prevent epithelial cell invasion and promote the epithelial expression of innate defense molecules. Given the protective role of tears a number of scenarios can be envisaged that may affect the amount and/or activity of tear antimicrobials and hence compromise tear immunity. Two such situations, dry eye disease and contact lens wear, are discussed here. PMID:23880529

  7. SIMULTANEOUS BILATERAL TEAR OF THE KNEE EXTENSOR MECHANISM IN A PRE-ADOLESCENT: CASE REPORT

    PubMed Central

    Albuquerque, Rodrigo Pires; Giordano, Vincenzo; Albuquerque, Maria Isabel Pires; Carvalho, Antonio Carlos Pires; do Amaral, Ney Pecegueiro; Barretto, João Maurício

    2015-01-01

    Unilateral tearing of a patellar tendon and a contralateral sleeve fracture in a pre-adolescent are rare lesions. We report a case in which a pre-adolescent sustained a fall while jumping during a soccer match. No predisposing risk factors were identified. The injuries were treated with surgical repairs and transosseous suturing. The aim of this study was to present a case of spontaneous concurrent tearing of the extensor mechanism of the knee in a pre-adolescent. PMID:27047882

  8. [Tear osmolarity and dry eye].

    PubMed

    Pan, Shi-yin; Xiao, Xiang-hua; Wang, Yang-zheng; Liu, Xian-ning; Zhu, Xiu-ping

    2011-05-01

    Dry eye is a common eye disease, and its incidence rate has been escalating. The increased tear osmolarity is one of the main reasons for complaint, damage and inflammation of dry eye patients. With the breakthrough of testing technology for tear osmolarity, more research and application of tear osmolarity was reported, and papers on tear osmolarity of normal eye and dry eye in different regions were also published. In this article, the progress of the tear osmolarity research, the range of tear osmolarity and its application in diagnosis and therapy of dry eye was introduced, and the prospect for the clinical application of hypotonic artificial tears was also discussed.

  9. Biceps tendinitis in chronic rotator cuff tears: a histologic perspective.

    PubMed

    Singaraju, Vamsi M; Kang, Richard W; Yanke, Adam B; McNickle, Allison G; Lewis, Paul B; Wang, Vincent M; Williams, James M; Chubinskaya, Susan; Romeo, Anthony A; Cole, Brian J

    2008-01-01

    Patients with chronic rotator cuff tears frequently have anterior shoulder pain attributed to the long head of the biceps brachii (LHBB) tendon. In this study, tenodesis or tenotomy samples and cadaveric controls were assessed by use of immunohistochemical and histologic methods to quantify inflammation, vascularity, and neuronal plasticity. Patients had moderate pain and positive results on at least 1 clinical test of shoulder function. The number of axons in the distal LHBB was significantly less in patients with biceps tendinitis. Calcitonin gene-related peptide and substance P immunostaining was predominantly within nerve roots and blood vessels. A moderate correlation (R = 0.5) was identified between LHBB vascularity and pain scores. On the basis of these results, we conclude that, in the context of rotator cuff disease, the etiology of anterior shoulder pain with macroscopic changes in the biceps tendon is related to the complex interaction of the tendon and surrounding soft tissues, rather than a single entity.

  10. Meniscus tears -- aftercare

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000684.htm Meniscus tears - aftercare To use the sharing features on this page, please enable JavaScript. The meniscus is a c-shaped piece of cartilage in ...

  11. Meniscus Tears (For Teens)

    MedlinePlus

    ... the inner part of the meniscus has no direct blood supply to help it heal. Tears in ... soccer, baseball, basketball, tennis, and racquetball taking a direct hit to the knee while playing a contact ...

  12. Histomorphometric and ultrastructural analysis of the tendon-bone interface after rotator cuff repair in a rat model

    PubMed Central

    Kanazawa, Tomonoshin; Gotoh, Masafumi; Ohta, Keisuke; Honda, Hirokazu; Ohzono, Hiroki; Shimokobe, Hisao; Shiba, Naoto; Nakamura, Kei-ichiro

    2016-01-01

    Successful rotator cuff repair requires biological anchoring of the repaired tendon to the bone. However, the histological structure of the repaired tendon-bone interface differs from that of a normal tendon insertion. We analysed differences between the normal tendon insertion and the repaired tendon-bone interface after surgery in the mechanical properties, histomorphometric analysis, and 3-dimensional ultrastructure of the cells using a rat rotator cuff repair model. Twenty-four adult Sprague-Dawley (SD) rats underwent complete cuff tear and subsequent repair of the supraspinatus tendon. The repaired tendon-bone interface was evaluated at 4, 8, and 12 weeks after surgery. At each time point, shoulders underwent micro-computed tomography scanning and biomechanical testing (N = 6), conventional histology and histomorphometric analysis (N = 6), and ultrastructural analysis with focused ion beam/scanning electron microscope (FIB/SEM) tomography (N = 4). We demonstrated that the cellular distribution between the repaired tendon and bone at 12 weeks after surgery bore similarities to the normal tendon insertion. However, the ultrastructure of the cells at any time point had a different morphology than those of the normal tendon insertion. These morphological differences affect the healing process, partly contributing to re-tearing at the repair site. These results may facilitate future studies of the regeneration of a normal tendon insertion. PMID:27647121

  13. 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

  14. The use of an intra-articular depth guide in the measurement of partial thickness rotator cuff tears.

    PubMed

    Carroll, Michael J; More, Kristie D; Sohmer, Stephen; Nelson, Atiba A; Sciore, Paul; Boorman, Richard; Hollinshead, Robert; Lo, Ian K Y

    2013-01-01

    Purpose. The purpose of this study was to compare the accuracy of the conventional method for determining the percentage of partial thickness rotator cuff tears to a method using an intra-articular depth guide. The clinical utility of the intra-articular depth guide was also examined. Methods. Partial rotator cuff tears were created in cadaveric shoulders. Exposed footprint, total tendon thickness, and percentage of tendon thickness torn were determined using both techniques. The results from the conventional and intra-articular depth guide methods were correlated with the true anatomic measurements. Thirty-two patients were evaluated in the clinical study. Results. Estimates of total tendon thickness (r = 0.41, P = 0.31) or percentage of thickness tears (r = 0.67, P = 0.07) using the conventional method did not correlate well with true tendon thickness. Using the intra-articular depth guide, estimates of exposed footprint (r = 0.92, P = 0.001), total tendon thickness (r = 0.96, P = 0.0001), and percentage of tendon thickness torn (r = 0.88, P = 0.004) correlated with true anatomic measurements. Seven of 32 patients had their treatment plan altered based on the measurements made by the intra-articular depth guide. Conclusions. The intra-articular depth guide appeared to better correlate with true anatomic measurements. It may be useful during the evaluation and development of treatment plans for partial thickness articular surface rotator cuff tears.

  15. Diseases of the tendons and tendon sheaths.

    PubMed

    Steiner, Adrian; Anderson, David E; Desrochers, André

    2014-03-01

    Contracted flexor tendon leading to flexural deformity is a common congenital defect in cattle. Arthrogryposis is a congenital syndrome of persistent joint contracture that occurs frequently in Europe as a consequence of Schmallenberg virus infection of the dam. Spastic paresis has a hereditary component, and affected cattle should not be used for breeding purposes. The most common tendon avulsion involves the deep digital flexor tendon. Tendon disruptions may be successfully managed by tenorrhaphy and external coaptation or by external coaptation alone. Medical management alone is unlikely to be effective for purulent tenosynovitis.

  16. [Controversies in the therapy of rotator cuff tears. Operative or nonoperative treatment, open or arthroscopic repair?].

    PubMed

    Lorbach, O

    2016-02-01

    Rotator cuff tears are a common cause of shoulder pain that may lead to severe impairment of shoulder function with significant limitation of the quality of life. Furthermore, they are associated with high direct and indirect costs.Conservative therapy and various surgical procedures for rotator cuff repair are all possible treatment options. Therefore, the correct treatment for a symptomatic rotator cuff tear is important.The conservative therapy may be considered as an alternative treatment option for a symptomatic rotator cuff tear in patients with small or incomplete tears with no fatty atrophy or tendon retraction, with only slight pain, and in older patients with few functional demands. Surgical treatment is recommended after failed conservative treatment lasting 3-6 months, with the corresponding psychological strain. Moreover, surgical treatment should be considered as a primary treatment option for a symptomatic rotator cuff tear in young patients with high functional demands, patients with a high level of physical strain in their jobs, large tears, and tears where there is already significant muscle atrophy or tendon retraction.Arthroscopic treatment is considered to be the gold standard because of the better cosmetic results and treatment of concomitant pathological conditions, the lower levels of postoperative pain, the potentially lower risk of shoulder stiffness, and more focused adhesiolysis. However, arthroscopy does not improve clinical results. Because of the current financial situation, however, open rotator cuff repair is still a viable alternative.

  17. Transverse Compression of Tendons.

    PubMed

    Salisbury, S T Samuel; Buckley, C Paul; Zavatsky, Amy B

    2016-04-01

    A study was made of the deformation of tendons when compressed transverse to the fiber-aligned axis. Bovine digital extensor tendons were compression tested between flat rigid plates. The methods included: in situ image-based measurement of tendon cross-sectional shapes, after preconditioning but immediately prior to testing; multiple constant-load creep/recovery tests applied to each tendon at increasing loads; and measurements of the resulting tendon displacements in both transverse directions. In these tests, friction resisted axial stretch of the tendon during compression, giving approximately plane-strain conditions. This, together with the assumption of a form of anisotropic hyperelastic constitutive model proposed previously for tendon, justified modeling the isochronal response of tendon as that of an isotropic, slightly compressible, neo-Hookean solid. Inverse analysis, using finite-element (FE) simulations of the experiments and 10 s isochronal creep displacement data, gave values for Young's modulus and Poisson's ratio of this solid of 0.31 MPa and 0.49, respectively, for an idealized tendon shape and averaged data for all the tendons and E = 0.14 and 0.10 MPa for two specific tendons using their actual measured geometry. The compression load versus displacement curves, as measured and as simulated, showed varying degrees of stiffening with increasing load. This can be attributed mostly to geometrical changes in tendon cross section under load, varying according to the initial 3D shape of the tendon.

  18. A comparison of different two-dimensional approaches for the determination of the patellar tendon moment arm length.

    PubMed

    Tsaopoulos, Dimitrios E; Baltzopoulos, Vasilios; Richards, Paula J; Maganaris, Constantinos N

    2009-03-01

    The purpose of this study was to estimate and compare the moment arm length of the patellar tendon (d) during passive knee extension using three different reference landmarks; instant centre of rotation (ICR), tibiofemoral contact point (TFCP) and geometrical centre of the posterior femoral condyles (GCFC). Measurements were taken on the right leg on seven healthy males during passive knee rotation performed by the motor of a Cybex Norm isokinetic dynamometer. Moment arms lengths were obtained by analysing lateral X-ray images recorded using a GE FlexiView 8800 C-arm videofluoroscopy system. The d-knee joint angle relations with respect to GCFC and ICR were similar, with decreasing values from full knee extension (~5.8 cm for d (GCFC) and ~5.9 cm for d (ICR)) to 90 degrees of knee flexion (~4.8 cm for both d (GCFC) and d (ICR)). However, the d (TFCP)-knee joint angle relation had an ascending-descending shape, with the highest d (TFCP) value (~5 cm) at 60 degrees of knee flexion. There was no significant difference between the GCFC and ICR methods at any knee joint angle. In contrast, there were significant differences (P < 0.01) between d (ICR) and d (TFCP) at 0 degrees , 15 degrees , 30 degrees and 45 degrees of knee flexion and between d (GCFC) and d (TFCP) at 0 degrees , 15 degrees and 30 degrees of knee flexion (P < 0.01). This study shows that when using different knee joint rotation centre definitions, there are significant differences in the estimates of the patellar tendon moment arm length, especially in more extended knee joint positions. These differences can have serious implications for joint modelling and loading applications.

  19. Tenotomy versus Tenodesis in the treatment of the long head of biceps brachii tendon lesions

    PubMed Central

    2012-01-01

    Background The superiority of tenotomy vs. tenodesis for surgery on lesions of the long head of the biceps brachii tendon is still under debate. Indeed, high-quality evidence is lacking, mainly because of methodological problems, such as retrospective design, population sample size or lack of patient randomization. Methods/Design The study will be a two-center, double-blind, randomized, controlled trial to compare patients treated with biceps tenotomy or tenodesis for lesions of the long head of the biceps brachii tendon over a 2-year follow-up period. The study participants will be 128 adults with biceps brachii tendinopathy and supraspinatus tendon tears. The primary end point will be the postoperative difference in the Constant-Murley score (CMS) between the 2 groups at the two-year follow-up. A comparison of the mean improvement with standard age- and gender-related CMS will be performed. The secondary end point will be evaluation of the postoperative general health of patients, as evaluated with Short Form 36 (SF-36) scores. The number and severity of complications associated with use of the different surgical techniques will be assessed. Discussion This study will be the first randomized and appropriately powered clinical trial to directly compare tenotomy and biceps tenodesis. The results of this study will help to establish clinical practice guidelines for patients suffering from lesions of the long head of the biceps brachii tendon, providing important information to patients and health care providers about the possible complications, outcome predictors and effectiveness of the targeted interventions. Trial Registration Current Controlled Trials ISRCTN38839558 PMID:23088416

  20. 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

  1. 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

  2. Surgical management of acute quadriceps tendon rupture (a case report with literature review)

    PubMed Central

    Ennaciri, Badr; Montbarbon, Eric; Beaudouin, Emmanuel

    2015-01-01

    Quadriceps tendon rupture is uncommon and often overlooked in emergency. Tearing affects weakening tendon by systemic diseases or some medications. The mechanism is generally indirect. Inability to actively extend the knee associated to a supra-patellar defect evoke easily the diagnosis without other investigations. Surgical repair is realized in emergency to completely restore the extension. We report a case of a patient who has sustained of complete quadriceps tendon tear after a long period of tendon weakening by statin therapy, hypertension and diabetes. The repair has consisted on end-to-end Krackow sutures associated with bone suture to the proximal pole of the patella. Surgeons and emergency physicians must think to this form of extensor apparatus rupture, because early diagnosis leads to early treatment and to best outcomes. PMID:26958106

  3. Nibbling Tears of Wine

    NASA Astrophysics Data System (ADS)

    Aristoff, Jeff; Bush, John

    2006-11-01

    The meniscus of an alcohol-rich solution is known to climb upwards due to an evaporation-induced Marangoni stress, thus initiating the tears of wine phenomenon. Rather than merging directly, the tears may bob up and down when they make contact with the underlying reservoir, appearing to nibble at its edge. We present a qualitative description of this flow and propose a simple theoretical model for this behavior. We thus rationalize the observed dependence of the nibbling frequency on the system parameters.

  4. Biomechanical and histological comparison of the influence of oestrogen deficient state on tendon healing potential in rats

    PubMed Central

    Akpinar, Sercan; Balcik, Cenk; Bacanli, Didem; Guven, Gulnur; Akgun, Rahmi Can; Tuncay, Ismail Cengiz

    2009-01-01

    Thirty-six female Sprague-Dawley rats were divided into two groups: oophrectomised (oestrogen deficient) rats and sham operated (oestrogen maintained) rats. Rats were sacrificed at six, ten, and 14 weeks. The rats were randomly chosen to have biomechanical evaluation on one side and histological evaluation on the other. Biomechanical testing was performed on an Instron machine to measure peak load. Histological sections were evaluated for cell proliferation, collagen-fibre organisation, fibroblast density, angiogenesis, inflammatory cells, chondroid and osseous metaplasia. Compared with the sham operated group, the oophrectomised group showed a lesser average maximum stress (42.9 N/m2 versus 33.7 N/m2) at six weeks, which was significant (p < .05). Succeeding weeks showed no significant biomechanical differences between the two groups. The sham operated group showed greater inflammatory response, which was statistically significant (p < 0.05), and also revealed greater cell proliferation and density. The results of this study revealed that endogenous oestrogen may improve healing of the Achilles tendon in rats. PMID:19387642

  5. 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

  6. 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.

  7. [Rotator cuff ruptures with predominant involvement of the subscapular tendon].

    PubMed

    Nérot, C; Jully, J L; Gérard, Y

    Among the all rotator cuff tears, the subscapularis lesions are quite rare. But a careful analysis leads to recognize them specially in case of antero-medial impingement between the coracoid process and the head of the humerus. This study of 25 observations where the rupture of the subscapularis was the predominant lesion, allows to emphasize some characteristics of them. The patients are often younger than for the other ruptures, a traumatic experience is not rare at the beginning of the history, the pain is usually the first symptom before the functional disability, the alterations of the rotator-interval and of the biceps tendon are very frequent, the arthroscanner is a very good help for the diagnosis and satisfying stitches are possible in case of early diagnoses. Lastly, the prognosis of these limited lesions is quite different than the one of very large cuff tears including the suscapularis tendon.

  8. Tears of Wine

    ERIC Educational Resources Information Center

    Gugliotti, Marcos

    2004-01-01

    The unique occurrence of the upward motion of a thin film of wine, and its formation into drops inside the wall of a wine glass is explained. Evaporation of alcohol generates a surface tension gradient, moving the film of wine upwards on the internal sides of a wine glass, where it collects and forms into drops or tears.

  9. Reconstruction of chronic tearing of the distal triceps using the double-row configuration: technical note.

    PubMed

    Paniago, Alexandre Firmino; Storti, Thiago Medeiros; Faria, Rafael Salomon Silva; Morais, Dennys Carlos Aragão de; Souza, Murillo Pablo de

    2015-01-01

    Tearing of the distal triceps is uncommon and may be difficult to diagnose, especially in situations of partial tearing. Imaging methods such as ultrasonography and magnetic resonance imaging should be used to confirm the diagnosis and define the extent of the injury. The preferred treatment for complete tearing of the triceps is surgical, unlike in cases of partial tearing, in which the treatment depends on factors such as pain, functional deficit and the patient's expectations. Here, we describe the case of a patient with partial tearing of the distal triceps after falling to the ground, which was not diagnosed at the time of first attendance and evolved with pain and great functional loss. The surgical procedure was performed nine months after the injury, with reconstruction of the triceps by means of reinforcement using the tendon of the ipsilateral semitendinosus and fixation in the olecranon using the double-row configuration. The patient remained immobilized using a sling for one week and then gains in passive range of motion (ROM) were introduced. Three weeks later, the patient was released for gains in active ROM. Muscle strengthening was started after 12 weeks. Six weeks after the surgical procedure, the patient was free from pain and presented complete ROM, grade V elbow extension force and hypertrophy of the triceps. The technique described here was shown to be useful for treating tears of the tendon of the distal triceps.

  10. Latissimus Dorsi Transfer in Posterior Irreparable Rotator Cuff Tears

    PubMed Central

    Anastasopoulos, Panagiotis P.; Alexiadis, George; Spyridonos, Sarantis; Fandridis, Emmanouil

    2017-01-01

    Background: Massive rotator cuff tears pose a difficult and complex challenge even for the experienced surgeon; inability to repair these tears by conventional means designates them as irreparable, while management becomes quite taxing. Several operative options have been suggested for the management of such lesions with varying degrees of success, while it is imperative to match patient demands and expectations to the predicted outcome. Methods: Research articles are examined and key concepts are discussed, in order to provide an evidence based review of the available literature. The anatomy and pathomechanics along with the indications, contraindications and surgical techniques are reported. Results: Transfer of the Latissimus dorsi has been used with success to restore shoulder function in deficits of the posterior rotator cuff. Although it can be used in a variety of settings, the ideal patient for a Latissimus dorsi tendon transfer is a young and active individual, with no glenohumeral osteoarthritis that has a severe disability and weakness related to an irreparable posterior cuff tear. Conclusion: Tendon transfers have proved to be a successful treatment option in salvaging this difficult problem, providing pain relief and restoring shoulder function. Despite the excellent functional outcomes and pain suppression following operation, a variety of factors may affect the outcome; thus making indications and preoperative assessment a valuable component.

  11. 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.

  12. Engineered stem cell niche matrices for rotator cuff tendon regenerative engineering

    PubMed Central

    Peach, M. Sean; Ramos, Daisy M.; Morozowich, Nicole L.; Mazzocca, Augustus D.; Doty, Steven B.; Allcock, Harry R.; Kumbar, Sangamesh G.; Laurencin, Cato T.

    2017-01-01

    Rotator cuff (RC) tears represent a large proportion of musculoskeletal injuries attended to at the clinic and thereby make RC repair surgeries one of the most widely performed musculoskeletal procedures. Despite the high incidence rate of RC tears, operative treatments have provided minimal functional gains and suffer from high re-tear rates. The hypocellular nature of tendon tissue poses a limited capacity for regeneration. In recent years, great strides have been made in the area of tendonogenesis and differentiation towards tendon cells due to a greater understanding of the tendon stem cell niche, development of advanced materials, improved scaffold fabrication techniques, and delineation of the phenotype development process. Though in vitro models for tendonogenesis have shown promising results, in vivo models have been less successful. The present work investigates structured matrices mimicking the tendon microenvironment as cell delivery vehicles in a rat RC tear model. RC injuries augmented with a matrix delivering rat mesenchymal stem cells (rMSCs) showed enhanced regeneration over suture repair alone or repair with augmentation, at 6 and 12-weeks post-surgery. The local delivery of rMSCs led to increased mechanical properties and improved tissue morphology. We hypothesize that the mesenchymal stem cells function to modulate the local immune and bioactivity environment through autocrine/paracrine and/or cell homing mechanisms. This study provides evidence for improved tendon healing with biomimetic matrices and delivered MSCs with the potential for translation to larger, clinical animal models. The enhanced regenerative healing response with stem cell delivering biomimetic matrices may represent a new treatment paradigm for massive RC tendon tears. PMID:28369135

  13. [Bilateral calcifying tendinitis of the long tendon of the biceps associated with a SLAP lesion].

    PubMed

    Mayayo Sinués, Esteban; Soriano Guillén, Antonia Pilar; Vela Marín, Ana Carmen; Martínez Pérez, Belén

    2010-01-01

    Calcifying tendinitis is a common disorder related to deposition of hidroxyapatite crystals, which is most common around the shoulder joint, involving the supraespinosus tendon. It can however, affect almost any tendon at its insertion. Clinical features are variable and include pain and inflammation that often resolves spontaneously. We present a case of bilateral calcifying tendinitis of the long head of the biceps tendon at its insertion on the superior glenoid rim associated with superior labrum antero-posterior tears (SLAP) confirmed by arthroscopy. Calcium deposits were surgically removed and the SLAP lesions were repaired.

  14. Biomimetic scaffold design for functional and integrative tendon repair.

    PubMed

    Zhang, Xinzhi; Bogdanowicz, Danielle; Erisken, Cevat; Lee, Nancy M; Lu, Helen H

    2012-02-01

    Rotator cuff tears represent the most common shoulder injuries in the United States. The debilitating effect of this degenerative condition coupled with the high incidence of failure associated with existing graft choices underscores the clinical need for alternative grafting solutions. The 2 critical design criteria for the ideal tendon graft would require the graft to not only exhibit physiologically relevant mechanical properties but also be able to facilitate functional graft integration by promoting the regeneration of the native tendon-to-bone interface. Centered on these design goals, this review will highlight current approaches to functional and integrative tendon repair. In particular, the application of biomimetic design principles through the use of nanofiber- and nanocomposite-based scaffolds for tendon tissue engineering will be discussed. This review will begin with nanofiber-based approaches to functional tendon repair, followed by a section highlighting the exciting research on tendon-to-bone interface regeneration, with an emphasis on implementation of strategic biomimicry in nanofiber scaffold design and the concomitant formation of graded multi-tissue systems for integrative soft-tissue repair. This review will conclude with a summary and discussion of future directions.

  15. Tendon and ligament imaging

    PubMed Central

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

    2012-01-01

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

  16. New Solution for Massive, Irreparable Rotator Cuff Tears: The Subacromial “Biodegradable Spacer”

    PubMed Central

    Savarese, Eugenio; Romeo, Rocco

    2012-01-01

    Massive, irreparable rotator cuff tears are a source of pain and disability. Although most rotator cuff tears can be completely repaired, a significant number are considered massive and irreparable. Numerous operative techniques have been described for the treatment of these kinds of tears including arthroscopic debridement, biceps tenotomy, tendon transfer, grafting, and reverse arthroplasty. We describe a surgical technique using a biodegradable subacromial balloon spacer (InSpace; OrthoSpace, Kfar Saba, Israel) implanted between the humeral head and acromion that permits smooth, frictionless gliding, restoring the shoulder biomechanics. The technique is easy to perform and is less invasive than the conventional surgical techniques available, and it may potentially serve as a bridging option in patients with massive, irreparable tears who are normally candidates for reverse arthroplasty. PMID:23766979

  17. Operative management of partial- and full-thickness rotator cuff tears.

    PubMed

    Franceschi, Francesco; Papalia, Rocco; Palumbo, Alessio; Del Buono, Angelo; Maffulli, Nicola; Denaro, Vincenzo

    2012-01-01

    Repair of rotator cuff tears (RCT) is challenging. In RC tears, a partial (PTRCTs) or full (RCTs) discontinuation of one or more of the muscles or tendons and may occur as a result of traumatic injury or degeneration over a period of years. Many factors seem to contribute to the final outcome and a considerable number of variations during the decision-making process of patients with RCTs exist. Accurate diagnosis is fundamental to guide correct management, and the tear pattern should be carefully evaluated to plan the appropriate repair. Both non-operative and operative treatments are used to relieve pain and restore movement and function of the shoulder. Different surgical options are available. The present review describes the current evidence about diagnosis and management of partial and complete rotator tears.

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

    PubMed Central

    2016-01-01

    Background Tendon-bone healing following rotator cuff repairs is mainly impaired by poor tissue quality. Demineralised bone matrix promotes healing of the tendon-bone interface but its role in the treatment of tendon tears with retraction has not been investigated. We hypothesized that cortical demineralised bone matrix used with minimally manipulated mesenchymal stem cells will result in improved function and restoration of the tendon-bone interface with no difference between xenogenic and allogenic scaffolds. Materials and Methods In an ovine model, the patellar tendon was detached from the tibial tuberosity and a complete distal tendon transverse defect measuring 1 cm was created. Suture anchors were used to reattach the tendon and xenogenic demineralised bone matrix + minimally manipulated mesenchymal stem cells (n = 5), or allogenic demineralised bone matrix + minimally manipulated mesenchymal stem cells (n = 5) were used to bridge the defect. Graft incorporation into the tendon and its effect on regeneration of the enthesis was assessed using histomorphometry. Force plate analysis was used to assess functional recovery. Results Compared to the xenograft, the allograft was associated with significantly higher functional weight bearing at 6 (P = 0.047), 9 (P = 0.028), and 12 weeks (P = 0.009). In the allogenic group this was accompanied by greater remodeling of the demineralised bone matrix into tendon-like tissue in the region of the defect (p = 0.015), and a more direct type of enthesis characterized by significantly more fibrocartilage (p = 0.039). No failures of tendon-bone healing were noted in either group. Conclusion Demineralised bone matrix used with minimally manipulated mesenchymal stem cells promotes healing of the tendon-bone interface in an ovine model of acute tendon retraction, with superior mechanical and histological results associated with use of an allograft. PMID:27606597

  19. COMPARISON BETWEEN THE RESULTS ACHIEVED IN ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION WITH TWO KINDS OF AUTOLOGOUS GRAFTS: PATELLAR TENDON VERSUS SEMITENDINOUS AND GRACILIS

    PubMed Central

    Abdalla, Rene Jorge; Monteiro, Diego Antico; Dias, Leonardo; Correia, Dárcio Maurício; Cohen, Moisés; Forgas, Andrea

    2015-01-01

    Objective: this study aims to compare the arthrometric and isokinetic examination results from two types of autologous grafts: the central third of the patellar ligament and a graft formed by the tendons of the semitendinosus and gracilis muscles, within the same rehabilitation protocol, six months after the surgery. Methods: the results from examinations carried out on 63 patients were analyzed. These patients were divided in two groups: one group of 30 patients who received a patellar tendon graft and another group of 33 patients who received a graft from the tendons of the semitendinosus and gracilis muscles. Both the grafts were attached in the same way, with Endobutton™ for suspensory fixation to the femur and a bioabsorbable interference screw for fixation in the tibial tunnel. Results: arthrometry 30 did not present any statistical difference between the two study groups. On the other hand, the isokinetic evaluation showed that the patellar tendon group had a larger mean peak torque of flexion and greater extension deficit, while the semitendinosus/gracilis group had a better mean flexion/extension ratio and greater percentage of flexion deficit. There was no statistically significant difference between the groups when measuring peak torque extension. Conclusion: therefore, when the patellar tendon was used, there was greater extensor deficit and, when the semitendinosus/gracilis tendons were used, there was greater flexor deficit. PMID:27004173

  20. Muscle architectural changes after massive human rotator cuff tear.

    PubMed

    Gibbons, Michael C; Sato, Eugene J; Bachasson, Damien; Cheng, Timothy; Azimi, Hassan; Schenk, Simon; Engler, Adam J; Singh, Anshuman; Ward, Samuel R

    2016-12-01

    Rotator cuff (RC) tendon tears lead to negative structural and functional changes in the associated musculature. The structural features of muscle that predict function are termed "muscle architecture." Although the architectural features of "normal" rotator cuff muscles are known, they are poorly understood in the context of cuff pathology. The purpose of this study was to investigate the effects of tear and repair on RC muscle architecture. To this end thirty cadaveric shoulders were grouped into one of four categories based on tear magnitude: Intact, Full-thickness tear (FTT), Massive tear (MT), or Intervention if sutures or hardware were present, and key parameters of muscle architecture were measured. We found that muscle mass and fiber length decreased proportionally with tear size, with significant differences between all groups. Conversely, sarcomere number was reduced in both FTT and MT with no significant difference between these two groups, in large part because sarcomere length was significantly reduced in MT but not FTT. The loss of muscle mass in FTT is due, in part, to subtraction of serial sarcomeres, which may help preserve sarcomere length. This indicates that function in FTT may be impaired, but there is some remaining mechanical loading to maintain "normal" sarcomere length-tension relationships. However, the changes resulting from MT suggest more severe limitations in force-generating capacity because sarcomere length-tension relationships are no longer normal. The architectural deficits observed in MT muscles may indicate deeper deficiencies in muscle adaptability to length change, which could negatively impact RC function despite successful anatomical repair. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2089-2095, 2016.

  1. [Tendon ruptures of the shoulder].

    PubMed

    Habermeyer, P

    1989-08-01

    Common sports, involving raising the arms above the head, i.e., throwing, racquet games and swimming, often result in rotator cuff tendinitis. During the throwing motion, the humeral head and its overlying biceps tendon and rotator cuff must pass rapidly under the coraco-acromial arch. Damage to these structures can occur by several mechanism. First, an increase in the size of the structures passing underneath the arch may lead to impingement. This can occur either by way of hypertrophy of the musculotendinous cuff or by way of inflammation of the cuff. Second, a decreased space available underneath the arch secondary to osteophyte formation of the acromion and fibrosis of the subacromial space may lead to impingement. Third, weakness or incompetence of the rotator cuff allows the humerus to ride up and impinge on the coracoacromial arch with motion of the shoulder. Tendinitis can be combined with increased laxity of the glenohumeral joint and/or acquired instability due to a labral tear. Prevention of overuse injuries is a cornerstone of our treatment concept. The muscle tendon unit requires passive and neuromuscular facilitated streching after warming-up exercises. Muscular imbalance and weakness are prevented by balanced eccentric strenthening with particular attention to the external rotators and scapular muscles. Knowledge of the mechanics of the pitching motion, tennis serve, swimming stroke, etc. is of paramount importance in the prevention of injuries. As the onset of shoulder problems contributes to a particularly fatiguing situation, extreme fatique performance severity should be avoided. Every effort must be made to apply conservative treatment when overuse problems arise in the athlete's shoulder.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. 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

  3. An Artificial Tendon with Durable Muscle Interface

    PubMed Central

    Melvin, Alan; Litsky, Alan; Mayerson, Joel; Witte, David; Melvin, David; Juncosa-Melvin, Natalia

    2010-01-01

    A coupling mechanism that can permanently fix a forcefully contracting muscle to a bone anchor or any totally inert prosthesis would meet a serious need in orthopaedics. Our group developed the OrthoCoupler™ device to satisfy these demands. The objective of this study was to test OrthoCoupler’s performance in vitro and in vivo in the goat semitendinosus tendon model. For in vitro evaluation, 40 samples were fatigue-tested, cycling at 10 load levels, n=4 each. For in vivo evaluation, the semitendinosus tendon was removed bilaterally in 8 goats. Left sides were reattached with an OrthoCoupler, and right sides were reattached using the Krackow stitch with #5 braided polyester sutures. Specimens were harvested 60 days post-surgery and assigned for biomechanics and histology. Fatigue strength of the devices in vitro was several times the contractile force of the semitendinosus muscle. The in vivo devices were built equivalent to two of the in vitro devices, providing an additional safety factor. In strength testing at necropsy, suture controls pulled out at 120.5 ± 68.3 N, whereas each OrthoCoupler was still holding after the muscle tore, remotely, at 298±111.3N (mean ± SD)(p<0.0003). Muscle tear strength was reached with the fiber-muscle composite produced in healing still soundly intact. This technology may be of value for orthopaedic challenges in oncology, revision arthroplasty, tendon transfer, and sports-injury reconstruction. PMID:19639642

  4. Evaluation of greater petrosal nerve function in patients with acute peripheral facial paralysis: comparison of soft palate electrogustometry and Schirmer's tear test.

    PubMed

    Kawamoto, Hidetoshi; Ikeda, Minoru

    2002-01-01

    We tested sensory and secretomotor function of the greater petrosal nerve (GPN) by means of electrogustometry (EGM) of the soft palate and Schirmer's tear test in 115 patients (59 males, 56 females) with acute peripheral facial paralysis. Facial paralysis was caused by Bell's palsy in 78 cases, Ramsay Hunt syndrome in 27 cases and zoster sine herpetic lesions in 10. All patients had dysfunction of the stapedial nerve. An electrogustometer was used to test taste (GPN sensory function), and elevation of the threshold by > 6 dB on the affected side was considered abnormal. Schirmer's test was used to evaluate lacrimal (GPN secretomotor) function, which was considered abnormal when tear secretion on the affected side was < 50% of secretion on the non-affected side. Of the 78 patients with Bell's palsy, 28.2% had altered taste on the soft palate (sensory dysfunction) and 10.3% had lacrimal dysfunction, indicating that EGM of the soft palate is more sensitive than Schirmer's test for identifying dysfunction of the GPN in patients with facial paralysis due to Bell's palsy. Of the total of 115 patients, 32 (28%) had taste dysfunction and 9 (28.1%) of these 32 patients also had lacrimal dysfunction. This finding indicates that facial paralysis has different effects on the sensory and secretory nerve fibers of the GPN. The results of Schirmer's test were more closely related to the severity of, and prognosis for, facial paralysis than the results of EGM.

  5. Forefoot tendon transfers.

    PubMed

    Veljkovic, Andrea; Lansang, Edward; Lau, Johnny

    2014-03-01

    Flexible forefoot deformities, such as hallux varus, clawed hallux, hammer toes, and angular lesser toe deformities, can be treated effectively with tendon transfers. Based on the presentation of the flexible forefoot deformities, tendon transfers can be used as the primary treatment or as adjuncts to bony procedures when there are components of fixed deformities.

  6. The tibialis posterior tendon.

    PubMed

    Lhoste-Trouilloud, A

    2012-02-01

    The tibialis posterior tendon is the largest and anteriormost tendon in the medial ankle. It produces plantar flexion and supination of the ankle and stabilizes the plantar vault. Sonographic assessment of this tendon is done with high-frequency, linear-array transducers; an optimal examination requires transverse retromalleolar, longitudinal retromalleolar, and distal longitudinal scans, as well as dynamic studies. Disorders of the posterior tibial tendon include chronic tendinopathy with progressive rupture, tenosynovitis, acute rupture, dislocation and instability, enthesopathies. The most common lesion is a progressive "chewing gum" lesion that develops in a setting of chronic tendinopathy; it is usually seen in overweight women over 50 years of age with valgus flat feet. Medial ankle pain must also be carefully investigated, and the presence of instability assessed with dynamic maneuvers (forced inversion, or dorsiflexion) of the foot. Sonography plays an important role in the investigation of disorders involving the posterior tibial tendon.

  7. Evidence of healing of partial-thickness rotator cuff tears following arthroscopic augmentation with a collagen implant: a 2-year MRI follow-up

    PubMed Central

    Bokor, Desmond John; Sonnabend, David; Deady, Luke; Cass, Ben; Young, Allan; Van Kampen, Craig; Arnoczky, Steven

    2016-01-01

    Summary Background partial-thickness rotator cuff tears frequently enlarge due to increased local strain and often progress to full-thickness tears. Studies suggest the addition of new tendinous tissue to injured cuff tendons would significantly decrease peak strain, possibly protecting against tear progression. The aim of this study was to assess the ability of a highly-porous collagen implant to induce new tissue formation and limit tear progression when placed on the bursal surface of partial-thickness cuff tears. Methods following arthroscopic subacromial decompression, the implant was attached to the bursal surface of the supraspinatus tendon in a prospective series of 13 consecutive patients with intermediate – (3–6 mm) to high-grade (>6 mm) partial – thickness cuff tears (5 articular, 3 bursal, 5 intra-substance). Tendon thickness, defect size, and tendon quality were evaluated using magnetic resonance imaging (MRI) preoperatively and at 3, 6, 12, and 24 months postoperatively. Clinical outcomes were assessed using the Constant and American Shoulder and Elbow Society scores at the same preoperative and follow-up times. All 13 patients completed all follow-up exams (mean length of follow-up 27.0 months, range 23.3–32.0); no patients were lost to follow-up. Results the implant induced significant new tissue formation in all patients by 3 months (mean increase in tendon thickness 2.2 ± 0.26 mm). This tissue matured over time and became radiologically indistinguishable from the underlying tendon. The partial-thickness cuff tears showed consistent filling of the defects, with complete healing in 7 patients at 12 months, and a progressive improvement in tendon quality in the remaining patients. No tear progression was observed by MRI in any of the patients at 24 months. All clinical scores improved significantly over time. At 24 months, 12 of 13 patients (92%) had satisfactory or better results. Conclusions the results of this clinical study demonstrated

  8. Tendinopathy of the tendon of the long head of the biceps.

    PubMed

    Longo, Umile Giuseppe; Loppini, Mattia; Marineo, Gianluca; Khan, Wasim S; Maffulli, Nicola; Denaro, Vincenzo

    2011-12-01

    Pathologies of tendon of the long head of the biceps (LHB) are an important cause of shoulder pain. They include tendinopathy, rupture, superior labrum anterior and posterior lesions, pulley tears, and tendon instability. Conservative management of symptomatic LHB tendinopathy is commonly accepted as the first-line treatment. It consists of rest, nonsteroidal anti-inflammatory drugs, corticosteroid injections, and physical therapy. Biceps tenotomy and tenodesis are the most common surgical procedures to manage both isolated LHB pathology and biceps-glenoid complex tears combined with rotator cuff tears. However, controversy persists about the superiority of one of them because there is no evidence of significant differences in functional scores or patient satisfaction between the 2 techniques. This article provides an overview on biomechanical function of the LHB and current strategies for treatment of LHB disorders.

  9. 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.

  10. Tendon gradient mineralization for tendon to bone interface integration.

    PubMed

    Qu, Jin; Thoreson, Andrew R; Chen, Qingshan; An, Kai-Nan; Amadio, Peter C; Zhao, Chunfeng

    2013-11-01

    Tendon-to-bone integration is a great challenge for tendon or ligament reconstruction regardless of use of autograft or allograft tendons. We mineralized the tendon, thus transforming the tendon-to-bone into a "bone-to-bone" interface for healing. Sixty dog flexor digitorum profundus (FDP) tendons were divided randomly into five groups: (1) normal FDP tendon, (2) CaP (non-extraction and mineralization without fetuin), (3) CaPEXT (Extraction by Na2 HPO4 and mineralization without fetuin), (4) CaPFetuin (non-extraction and mineralization with fetuin), and (5) CaPEXTFetuin (extraction and mineralization with fetuin). The calcium and phosphate content significantly increased in tendons treated with combination of extraction and fetuin compared to the other treatments. Histology also revealed a dense mineral deposition throughout the tendon outer layers and penetrated into the tendon to a depth of 200 µm in a graded manner. Compressive moduli were significantly lower in the four mineralized groups compared with normal control group. No significant differences in maximum failure strength or stiffness were found in the suture pull-out test among all groups. Mineralization of tendon alters the interface from tendon to bone into mineralized tendon to bone, which may facilitate tendon-to-bone junction healing following tendon or ligament reconstruction.

  11. Modeling Tear Film Dynamics on a 2-D Eye-shaped Domain

    NASA Astrophysics Data System (ADS)

    Li, Longfei; Braun, Richard; Maki, Kara; Henshaw, William

    2012-11-01

    We study tear film dynamics on a 2-D eye-shaped domain using a lubrication model. Time dependent flux boundary conditions that model the lacrimal gland tear supply and punctal drainage are imposed. We solved the model equations with Overture computational framework. Results reveals our model captures the hydraulic connectivity and other key physics of human tear film observed in vivo. Comparisons are made with existing models and experiments. Should time permit, osmolarity dynamics (salt ion concentration) will be included.

  12. Tear Film Lipids

    PubMed Central

    Butovich, Igor A.

    2013-01-01

    Human meibomian gland secretions (MGS, or meibum) are formed from a complex mixture of lipids of different classes such as wax esters, cholesteryl esters, (O-acyl)-ω-hydroxy fatty acids (OAHFA) and their esters, acylglycerols, diacylated diols, free fatty acids, cholesterol, and a smaller amount of other polar and nonpolar lipids, whose chemical nature and the very presence in MGS have been a matter of intense debates. The purpose of this review is to discuss recent results that were obtained using different experimental techniques, estimate limitations of their usability, and discuss their biochemical, biophysical, and physiological implications. To create a lipid map of MGS and tears, the results obtained in the author’s laboratory were integrated with available information on chemical composition of MGS and tears. The most informative approaches that are available today to researchers, such as HPLC-MS, GC-MS, and proton NMR, are discussed in details. A map of the meibomian lipidome (as it is seen in reverse phase liquid chromatography/mass spectrometry experiments) is presented. Directions of future efforts in the area are outlined. PMID:23769846

  13. Infraspinatus/Teres minor transfer biceps in situ tenodesis procedure: initial results of a technique for massive cuff tears.

    PubMed

    Fletcher, Matt D A

    2013-01-01

    Massive rotator cuff tears may not be primarily repairable with salvage options not necessarily providing acceptable results. Extrinsic tendon transfer is a significant undertaking with prolonged rehabilitation and variable outcome. A novel technique for the reconstruction of massive tears, not amenable to primary repair, by performing a transfer of the intrinsic posterior rotator cuff onto an intact, tenodesed long head of biceps tendon acting as a scaffold for the intrinsic transfer is described. The clinical results at short to medium term in 17 initial patients are presented. Encouraging results from this study suggest that this is a viable option for the management of massive rotator cuff tears with an intact posterior cuff with results equal or superior to other reconstructive techniques.

  14. Tendoscopy in stage I posterior tibial tendon dysfunction.

    PubMed

    Khazen, Gabriel; Khazen, Cesar

    2012-09-01

    Stage I PTTD was defined by Johnson and Strom as tenosynovitis or tendinitis whereby tendon length remains normal, there is no hindfoot deformity, and diagnosis is basically clinical, characterized by swelling and tenderness posterior to the medial malleolus. The PTT has a hypovascular zone 40 mm proximal to the insertion of the tendon and 14 mm in length. Pain often is localized to this portion of the tendon. Tendon power might be normal, and the patient can perform single heel rise, sometimes with slight discomfort. This condition is often misdiagnosed as ankle sprain, which delays correct diagnosis and early treatment that may improve symptoms, stop the disease process, and prevent the development of adult acquired flatfoot deformity. Ultrasonography is a valuable adjunctive diagnostic tool for stage I PTTD, but the authors always indicate MRI for accurate diagnosis in such patients. Patients with stage I PTTD are first treated nonoperatively with nonsteroidal anti-inflammatory drugs for 5 days, cryotherapy, local ultrasound, and a PTTD airlift brace (Aircast) for 3 to 6 months. If symptoms persist, surgical debridement and synovectomy has been suggested. PTT tendoscopic synovectomy is a minimally invasive and effective surgical procedure to treat patients with stage I PTTD. It has the advantages of less wound pain, and fewer scar and wound problems. If tendon tear is observed during tendoscopy, it must be repaired with nonabsorbable sutures using a 3- or 4-cm incision.

  15. Symptomatic intratendinous ganglion cyst of the patellar tendon.

    PubMed

    Jose, Jean; O'Donnell, Kevin; Lesniak, Bryson

    2011-01-01

    Ganglion cysts have been previously described throughout the body, most commonly about the wrist, hand, knee, ankle, and feet. When symptomatic, they may interfere with joint mechanics, resulting in snapping, catching, and locking. Intratendinous ganglion cysts lack a synovial epithelial lining and are thought to develop from the mucoid degeneration of connective tissue caused by chronic irritation, chronic repetitive injury, and chronic ischemia. On magnetic resonance imaging, ganglion cysts originating from tendons, ligaments, tendon sheaths, menisci, or joint capsules appear as well-defined lobulated masses that follow simple or complex fluid signal intensity on all pulse sequences, with enhancing walls and internal septations on post-contrast images. There may be appreciable degeneration and partial tearing of the structure of origin, particularly if associated with tendons. On ultrasonography, they present as hypoechoic masses, with internal septations and lobulations of varying sizes, without significant vascularity on power or color Doppler sampling. A thin fluid neck extending from the structure of origin (tail sign), when present, is a reliable sign of a ganglion cyst. This article describes a sonographically guided technique to treat symptomatic ganglion cysts within the patellar tendon. Complete evacuation of the ganglion cyst, with disappearance of the tail sign, is considered the determining factor for a successful procedure. A similar technique can be used for the treatment of other symptomatic intratendinous ganglion cysts elsewhere in the body. To our knowledge, symptomatic intratendinous ganglion cysts within the patellar tendon and their treatment have not been previously reported.

  16. Autologous tenocyte implantation, a novel treatment for partial-thickness rotator cuff tear and tendinopathy in an elite athlete.

    PubMed

    Wang, Allan W; Bauer, Stefan; Goonatillake, Matthew; Breidahl, William; Zheng, Ming-Hao

    2013-01-11

    Tendinopathy and small partial-thickness tears of the rotator cuff tendon are common presentations in sports medicine. No promising treatment has yet been established. Corticosteroid injections may improve symptoms in the short term but do not primarily treat the tendon pathology. Ultrasound-guided autologous tenocyte implantation (ATI) is a novel bioengineered treatment approach for treating tendinopathy. We report the first clinical case of ATI in a 20-year-old elite gymnast with a rotator cuff tendon injury. The patient presented with 12 months of increasing pain during gymnastics being unable to perform most skills. At 1 year after ATI the patient reported substantial improvement of clinical symptoms. Pretreatment and follow-up MRIs were reported and scored independently by two experienced musculoskeletal radiologists. Tendinopathy was improved and the partial-thickness tear healed on 3 T MRI. The patient was able to return to national-level competition.

  17. Autologous tenocyte implantation, a novel treatment for partial-thickness rotator cuff tear and tendinopathy in an elite athlete

    PubMed Central

    Wang, Allan W; Bauer, Stefan; Goonatillake, Matthew; Breidahl, William; Zheng, Ming-Hao

    2013-01-01

    Tendinopathy and small partial-thickness tears of the rotator cuff tendon are common presentations in sports medicine. No promising treatment has yet been established. Corticosteroid injections may improve symptoms in the short term but do not primarily treat the tendon pathology. Ultrasound-guided autologous tenocyte implantation (ATI) is a novel bioengineered treatment approach for treating tendinopathy. We report the first clinical case of ATI in a 20-year-old elite gymnast with a rotator cuff tendon injury. The patient presented with 12 months of increasing pain during gymnastics being unable to perform most skills. At 1 year after ATI the patient reported substantial improvement of clinical symptoms. Pretreatment and follow-up MRIs were reported and scored independently by two experienced musculoskeletal radiologists. Tendinopathy was improved and the partial-thickness tear healed on 3 T MRI. The patient was able to return to national-level competition. PMID:23314880

  18. FUNCTIONAL EVALUATION OF PATIENTS WHO HAVE UNDERGONE ARTHROSCOPIC DEBRIDEMENT TO TREAT MASSIVE AND IRREPARABLE TEARS OF THE ROTATOR CUFF

    PubMed Central

    Veado, Marco Antônio de Castro; Rodrigues, Alessandro Ulhôa

    2015-01-01

    To evaluate the results from patients who underwent arthroscopic debridement of extensive irreparable rotator cuff injuries. Methods: 27 patients were operated between 2003 and 2007, and 22 of them were evaluated. The surgical procedure consisted of arthroscopic debridement of the stumps of the tendons involved, bursectomy, removal of acromial osteophytes and, possibly, biceps tenotomy and tuberoplasty. Results: All the patients showed involvement of the supraspinatus and infraspinatus tendons at the preoperative stage. In the postoperative evaluation, 14 patients had a complete teres minor muscle, and three had partial tears of the subscapularis tendon. There was an improvement in the UCLA criteria, from 15 preoperatively to 31 postoperatively. There was no improvement in muscle strength, but there was a reduction in the pain. Conclusion: Arthroscopic debridement is a recommended procedure for elderly patients with irreparable rotator cuff tears, good range of motion and low functional demand, when the main objective is to diminish pain. PMID:27022590

  19. Tear-ducts in wine

    NASA Astrophysics Data System (ADS)

    Bush, John W. M.

    1999-11-01

    We examine the radial spoke pattern evident in the meniscus region in glasses of strong alcoholic beverages exhibiting the `tears-in-wine' phenomenon. We demonstrate that the pattern results from ridge-like elevations of the free surface which are supported by evaporatively-driven Marangoni convection in the meniscus region. Vortices associated with the convective motions are aligned in the radial direction by the surface tension gradient responsible for the generation of tears. The radial flow is focussed into the ridges, which thus serve as the principal conduits of fluid for the tears; consequently, we refer to the ridges as `tear-ducts'. The phenomenon is examined experimentally, and a numerical model of evaporatively-driven Marangoni convection is developed which reproduces the salient features of the tear-duct phenomenon.

  20. Effects of corticosteroids and hyaluronic acid on torn rotator cuff tendons in vitro and in rats.

    PubMed

    Nakamura, Hidehiro; Gotoh, Masafumi; Kanazawa, Tomonoshin; Ohta, Keisuke; Nakamura, Keiichirou; Honda, Hirokazu; Ohzono, Hiroki; Shimokobe, Hisao; Mitsui, Yasuhiro; Shirachi, Isao; Okawa, Takahiro; Higuchi, Fujio; Shirahama, Masahiro; Shiba, Naoto; Matsueda, Satoko

    2015-10-01

    Corticosteroids (CS) or hyaluronic acid (HA) is used in subacromial injection for the conservative treatment of rotator cuff tears (RCT); this study addresses the question of how CS and HA affect the tendon tissue and fibroblasts in vitro and in rats. Cell proliferation assays were performed in human tendon fibroblasts from RCT. Rats underwent surgery to create RCT, and the surgical sites were injected with CS or HA. The rotator cuff tendons were subjected to biomechanical testing, microscopic and immunohistochemical analysis of proliferating cell nuclear antigen (PCNA), and ultrastructural analysis. Cell proliferation was significantly decreased with CS in vitro (p < 0.05). Maximal load of CS-treated tendons was significantly decreased compared with that of HA-treated tendons (p < 0.05), as well as PCNA(+) cells at 2 weeks (p < 0.05). Ultrastructural observations of the CS-treated rats detected apoptosis of tendon fibroblasts 24 h after surgery. Histological and biomechanical data 4 weeks after surgery were not significant among the three groups. Unlike HA, CS caused cell death, and inhibition of the proliferation of tendon fibroblasts, leading to a delay of tendon healing involved and a subsequent decrease of biomechanical strength at the surgical site.

  1. Proximal Biceps Tendonitis

    MedlinePlus

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

  2. 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.

  3. [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.

  4. Rehabilitating Psoas Tendonitis: A Case Report

    PubMed Central

    2008-01-01

    This case report describes the examination and physical therapy intervention for a woman with anterior hip pain whose medical diagnosis following magnetic resonance imaging (MRI) was bilateral labral tears and psoas tendinitis. Her physical therapy evaluation revealed findings consistent with psoas tendonitis. Utilizing theories of neuromuscular patterning and knowledge of normal muscle function, the patient was successfully treated in physical therapy following six physical therapy sessions, once a week for 6 weeks. The patient was found to have an overactive psoas muscle, as indicated by hip flexion being the primary mover in her movement patterns, and dysfunctional abdominal and pelvic floor muscles. Functionally based therapeutic exercise and electrical stimulation were used to reeducate the muscles of the abdomen, pelvic floor, and hips in order to create muscular balance and correct muscle dysfunction. PMID:19048347

  5. Tear Film Dynamics Around a Rigid Model Blob

    NASA Astrophysics Data System (ADS)

    Ketelaar, Christiaan; Zhong, Lan; Braun, Rj; Driscoll, Ta; King-Smith, Pe; Begley, Cg

    2015-11-01

    Tear film break up (TBU) can occur after imperfections in the lipid layer arise. The imperfections may cause elevated evaporation, which causes TBU for large enough spots and grooves and for fast enough evaporation. TBU also occurs near smaller features in the lipid layer. These are apparently blobs of lipids that do not spread and which are too small for the evaporative mechanism to account for the dynamics. We investigate the tear film dynamics near a model rigid blob with a fixed constant surfactant concentration. We develop the lubrication-type equations that govern the tear film thickness, surfactant concentration, and osmolarity in the tear film beneath and near the blob. We perform numerical simulations for the evolution of the tear film thickness and analyze how the size of the blob, as well as the surfactant properties and transport, affect tear film dynamics. The thinning induced by the blob is of the correct time scale to compare with in vivo observations, and close comparison with the experiments will be made.

  6. On tear film breakup (TBU): dynamics and imaging.

    PubMed

    Braun, Richard J; Driscoll, Tobin A; Begley, Carolyn G; King-Smith, P Ewen; Siddique, Javed I

    2017-02-20

    We report the results of some recent experiments to visualize tear film dynamics. We then study a mathematical model for tear film thinning and tear film breakup (TBU), a term from the ocular surface literature. The thinning is driven by an imposed tear film thinning rate which is input from in vivo measurements. Solutes representing osmolarity and fluorescein are included in the model. Osmolarity causes osmosis from the model ocular surface, and the fluorescein is used to compute the intensity corresponding closely to in vivo observations. The imposed thinning can be either one-dimensional or axisymmetric, leading to streaks or spots of TBU, respectively. For a spatially-uniform (flat) film, osmosis would cease thinning and balance mass lost due to evaporation; for these space-dependent evaporation profiles TBU does occur because osmolarity diffuses out of the TBU into the surrounding tear film, in agreement with previous results. The intensity pattern predicted based on the fluorescein concentration is compared with the computed thickness profiles; this comparison is important for interpreting in vivo observations. The non-dimensionalization introduced leads to insight about the relative importance of the competing processes; it leads to a classification of large vs small TBU regions in which different physical effects are dominant. Many regions of TBU may be considered small, revealing that the flow inside the film has an appreciable influence on fluorescence imaging of the tear film.

  7. Meniscal tear film fluid dynamics near Marx's line.

    PubMed

    Zubkov, V S; Breward, C J W; Gaffney, E A

    2013-09-01

    Extensive studies have explored the dynamics of the ocular surface fluid, though theoretical investigations are typically limited to the use of the lubrication approximation, which is not guaranteed to be uniformly valid a-priori throughout the tear meniscus. However, resolving tear film behaviour within the meniscus and especially its apices is required to characterise the flow dynamics where the tear film is especially thin, and thus most susceptible to evaporatively induced hyperosmolarity and subsequent epithelial damage. Hence, we have explored the accuracy of the standard lubrication approximation for the tear film by explicit comparisons with the 2D Navier-Stokes model, considering both stationary and moving eyelids. Our results demonstrate that the lubrication model is qualitatively accurate except in the vicinity of the eyelids. In particular, and in contrast to lubrication theory, the solution of the full Navier-Stokes equations predict a distinct absence of fluid flow, and thus convective mixing in the region adjacent to the tear film contact line. These observations not only support emergent hypotheses concerning the formation of Marx's line, a region of epithelial cell staining adjacent to the contact line on the eyelid, but also enhance our understanding of the pathophysiological consequences of the flow profile near the tear film contact line.

  8. Comparison of the Clinical and Radiological Oucomes of Conventional Double row and Double row Suture Bridge Repairs in Rotator Cuff Tears

    PubMed Central

    Muiño, José María Silberberg; Gimenez, Martín Alejandro; Salvucci, Mauro Gabriel Maroa; Ferro, Diego; Rullan, Ramón Muiña; Blanchero, Pablo

    2017-01-01

    Objectives: To compare clinical and radiological results of two types of rotator cuff (RC) repairs: the double row and double row-suture bridge. Methods: Forty-two patients with a complete tear (medium and large size) of the RC were repaired by a double row arthroscopic technique. Minimum follow-up was 19 months (range, 19-28 months). Clinical outcomes were assessed by the Modified Constant Scale and satisfaction rate by an independent observer; VAS, UCLA and ASES. Radiological results were assed by a postoperative MRI by a musculoskeletal radiologist. Results: Series of 22 patients in the double row technique (Group A) and 20 patients in the double-row suture bridge (Gruop B). Statistically there was a significant improvement in the Constant Scale, satisfaction rate, muscle assessment, VAS, UCLA and ASES in both groups after the surgical procedure. There were no significant clinical differences between both groups at any time after the surgical procedure. According to MRI postop, 19/22 shoulders in Group A and 18/20 in Group B remained intact, with no significant differences between the two groups. Conclusion: RC repairs with double row and double-row-suture bridge techniques provide clinical and radiological good and excelent results. In our retrospective, mid-size study, we have found no differences between these two repair techniques.

  9. Characterization of protein adsorption on soft contact lenses. IV. Comparison of in vivo spoilage with the in vitro adsorption of tear proteins.

    PubMed

    Castillo, E J; Koenig, J L; Anderson, J M

    1986-03-01

    Tear protein and gamma-globulin mixtures were adsorbed on soft contact lenses of different chemical composition, surface quality and water content. The adsorption process was followed by Fourier transform infrared-attenuated total reflectance spectroscopy (ATR-FTIR). It was found that gamma-globulin underwent a conformational and orientational change after its adsorption and the extent of structural change appeared to be proportional to the binding strength of the protein with the hydrogel surface. Electrostatic interactions play a major role in the protein adsorption on lenses containing methacrylic acid. Lysozyme is selectively adsorbed on all of the high water content hydrogels and mucin is the major protein component for the pure PHEMA type of lenses. Studies on in vivo spoiled PHEMA and PVP/MMA lenses indicate that lysozyme is the major adsorbed deposit. Papain cleaning of in vivo spoiled lenses shows that although a portion of the deposits is desorbed, the enzyme itself becomes irreversibly adsorbed to the contact lens which may cause harmful effects to the eye.

  10. Electronic enhancement of tear secretion

    NASA Astrophysics Data System (ADS)

    Brinton, Mark; Lim Chung, Jae; Kossler, Andrea; Kook, Koung Hoon; Loudin, Jim; Franke, Manfred; Palanker, Daniel

    2016-02-01

    Objective. To study electrical stimulation of the lacrimal gland and afferent nerves for enhanced tear secretion, as a potential treatment for dry eye disease. We investigate the response pathways and electrical parameters to safely maximize tear secretion. Approach. We evaluated the tear response to electrical stimulation of the lacrimal gland and afferent nerves in isofluorane-anesthetized rabbits. In acute studies, electrical stimulation was performed using bipolar platinum foil electrodes, implanted beneath the inferior lacrimal gland, and a monopolar electrode placed near the afferent ethmoid nerve. Wireless microstimulators with bipolar electrodes were implanted beneath the lacrimal gland for chronic studies. To identify the response pathways, we applied various pharmacological inhibitors. To optimize the stimulus, we measured tear secretion rate (Schirmer test) as a function of pulse amplitude (1.5-12 mA), duration (0.1-1 ms) and repetition rate (10-100 Hz). Main results. Stimulation of the lacrimal gland increased tear secretion by engaging efferent parasympathetic nerves. Tearing increased with stimulation amplitude, pulse duration and repetition rate, up to 70 Hz. Stimulation with 3 mA, 500 μs pulses at 70 Hz provided a 4.5 mm (125%) increase in Schirmer score. Modulating duty cycle further increased tearing up to 57%, compared to continuous stimulation in chronically implanted animals (36%). Ethmoid (afferent) nerve stimulation increased tearing similar to gland stimulation (3.6 mm) via a reflex pathway. In animals with chronically implanted stimulators, a nearly 6 mm increase (57%) was achieved with 12-fold less charge density per pulse (0.06-0.3 μC mm-2 with 170-680 μs pulses) than the damage threshold (3.5 μC mm-2 with 1 ms pulses). Significance. Electrical stimulation of the lacrimal gland or afferent nerves may be used as a treatment for dry eye disease. Clinical trials should validate this approach in patients with aqueous tear deficiency, and

  11. Clinical presentation and imaging results of patients with symptomatic gluteus medius tears

    PubMed Central

    Lindner, Dror; Shohat, Noam; Botser, Itamar; Agar, Gabriel; Domb, Benjamin G.

    2015-01-01

    Greater trochanteric pain syndrome (GTPS) is a common complaint. Recently, it has become well recognized that tendinopathy and tears of the gluteus medius (GM) are a cause of recalcitrant GTPS. Nevertheless, the clinical syndrome associated with GM tears is not fully characterized. We characterize the clinical history, findings on physical examination, imaging and intraoperative findings associated with symptomatic GM tears. Forty-five patients (47 hips) who underwent GM repair for the diagnosis of tear were evaluated. Pain was estimated on the visual analog scale (VAS) and hip-specific scores were administered to assess functional status. The imaging modalities were reviewed and intra operative findings were recorded. The average patient age was 54 years (17–76), 93% were females. Symptom onset was commonly insidious (75%) and the average time to diagnosis was 28 months (2–240). The most common pain location was the lateral hip (75%). The average pre-surgery VAS and modified Harris Hip Score were 6.65 (0–10) and 55.5 (12–90), respectively. All patients had pathological findings on magnetic resonance angiogram (MRA) ranging from tendinosis to complete tears of the GM tendon. There was a discrepancy between MRA interpretation by a radiologist and findings during surgery. Hip abductor tears are an under-recognized cause of hip pain and hip symptomatology. In this study, we further characterize the clinical presentation of this entity. The data we present here may facilitate early diagnosis, early orthopedic care and avoid unnecessary prolonged patient sufferings. PMID:27011854

  12. Radiostereometric Evaluation of Tendon Elongation After Distal Biceps Repair

    PubMed Central

    Marshall, Nathan E.; Keller, Robert A.; Okoroha, Kelechi; Guest, John Michael; Yu, Charles; Muh, Stephanie; Moutzouros, Vasilios

    2016-01-01

    Background: Operative repair of distal biceps tendon ruptures has shown successful outcomes. However, little is known about the amount of tendon or repair site lengthening after repair. Purpose/Hypothesis: The purpose of this study was to evaluate distal biceps tendon repair via intratendinous radiostereometric analysis to analyze tendon lengthening at different time intervals of healing. The hypothesis was that there is significant lengthening after repair. Study Design: Case series; Level of evidence, 4. Methods: Eleven patients with distal biceps ruptures requiring operative repair were recruited. During repair, two 2-mm tantalum beads with laser-etched holes were sutured to the distal biceps tendon. Beads were evaluated via computed tomography scans immediately postoperatively and at 16 weeks. Radiographs were obtained at time 0 and then at 4, 8, and 16 weeks postoperatively. Measurements were made using the button-to-bead and bead-to-bead distances to assess repair site elongation as well as tendon elongation over time. After final follow-up, patients filled out the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and underwent ultrasound to confirm the integrity of the tendon. Results: Ten patients had complete ruptures, with 1 having a partial rupture that underwent completion of the tear and subsequent repair. All patients showed statistically significant lengthening after surgery. The mean amount of tendon lengthening after surgery was 22.8 mm (range, 11.2-30.9 mm; P < .05), and the repair site lengthened a mean 17.0 mm (range, 9.6-30.6 mm; P < .05) from surgery to final follow-up. The greatest change in lengthening was noted between time 0 and week 4 (mean, 11.3 mm; P < .05), with the least amount of lengthening between weeks 8 and 16 (mean, 2.6 mm; P < .05). The mean DASH score was 11.2. Final ultrasound evaluations found all tendons to be in continuity. Conclusion: All patients undergoing distal biceps tendon repair have significant

  13. 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.

  14. Pectoralis Major Tear: An Unusual and Rare Presentation

    PubMed Central

    Kadu, Vikram V; Saindane, K A; Godghate, Ninad; Godghate, Neha

    2016-01-01

    Introduction: The pectoralis major is a very powerful muscle that forms the chest prominence and. It moves the shoulder forward and across your chest. It is best known as the muscle that you develop with the bench press exercise in gymnasium. The pectoralis major attaches to the humerus bone and is divided into two parts. The upper part is known as the “clavicular head” and the lower part the “sternal head,” based on their origins from the clavicle and sternal bones, respectively. Ruptures of the pectoralis major muscle are becoming more common due to the increase in power sports weight training. Case Report: A About 25-year-old male presented to Out Patient Department with bruising and swelling over the anterior wall of left axilla. The patient was engineer and amateur weight lifter. Clinically, the swelling was tender, and movements of left arm were restricted. Muscle tear was suspected and hence magnetic resonance imaging (MRI) was advised which showed tear of tendon of pectoralis major muscle. The patient was treated surgically and has got full range of movements of the arm. Conclusion: MRI is the mainstay for diagnosing pectoralis major tear. The earlier a repair is performed the easier the surgery and the better the outcome of surgery. PMID:27299117

  15. Tendon transfer or tendon graft for ruptured finger extensor tendons in rheumatoid hands.

    PubMed

    Chung, U S; Kim, J H; Seo, W S; Lee, K H

    2010-05-01

    We evaluated the clinical outcome of tendon reconstruction using tendon graft or tendon transfer and the parameters related to clinical outcome in 51 wrists of 46 patients with rheumatoid arthritis with finger extensor tendon ruptures. At a mean follow-up of 5.6 years, the mean metacarpophalangeal (MP) joint extension lag was 8 degrees (range, 0-45) and the mean visual analogue satisfaction scale was 74 (range, 10-100). Clinical outcome did not differ significantly between tendon grafting and tendon transfer. The MP joint extension lag correlated with the patient's satisfaction score, but the pulp-to-palm distance did not correlate with patient satisfaction. We conclude that both tendon grafting and tendon transfer are reliable reconstruction methods for ruptured finger extensor tendons in rheumatoid hands.

  16. 49 CFR 178.1070 - Tear test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tear test. 178.1070 Section 178.1070... Containers § 178.1070 Tear test. (a) General. The tear test must be conducted for the qualification of all of Flexible Bulk Containers design types. (b) Special preparation for the tear test. Flexible Bulk...

  17. 49 CFR 178.818 - Tear test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tear test. 178.818 Section 178.818 Transportation... Tear test. (a) General. The tear test must be conducted for the qualification of all flexible IBC design types. (b) Special preparation for the tear test. The flexible IBC must be filled to not less...

  18. 49 CFR 178.818 - Tear test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Tear test. (a) General. The tear test must be conducted for the qualification of all flexible IBC design types. (b) Special preparation for the tear test. The flexible IBC must be filled to not less than... 49 Transportation 3 2011-10-01 2011-10-01 false Tear test. 178.818 Section 178.818...

  19. 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.

  20. 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.

  1. Influence of Rotator Cuff Tear Size and Repair Technique on the Creation and Management of Dog Ear Deformities in a Transosseous-Equivalent Rotator Cuff Repair Model

    PubMed Central

    Redler, Lauren H.; Byram, Ian R.; Luchetti, Timothy J.; Tsui, Ying Lai; Moen, Todd C.; Gardner, Thomas R.; Ahmad, Christopher S.

    2014-01-01

    Background: Redundancies in the rotator cuff tissue, commonly referred to as “dog ear” deformities, are frequently encountered during rotator cuff repair. Knowledge of how these deformities are created and their impact on rotator cuff footprint restoration is limited. Purpose: The goals of this study were to assess the impact of tear size and repair method on the creation and management of dog ear deformities in a human cadaveric model. Study Design: Controlled laboratory study. Methods: Crescent-shaped tears were systematically created in the supraspinatus tendon of 7 cadaveric shoulders with increasing medial to lateral widths (0.5, 1.0, and 1.5 cm). Repair of the 1.5-cm tear was performed on each shoulder with 3 methods in a randomized order: suture bridge, double-row repair with 2-mm fiber tape, and fiber tape with peripheral No. 2 nonabsorbable looped sutures. Resulting dog ear deformities were injected with an acrylic resin mixture, digitized 3-dimensionally (3D), and photographed perpendicular to the footprint with calibration. The volume, height, and width of the rotator cuff tissue not in contact with the greater tuberosity footprint were calculated using the volume injected, 3D reconstructions, and calibrated photographs. Comparisons were made between tear size, dog ear measurement technique, and repair method utilizing 2-way analysis of variance and Student-Newman-Keuls multiple-comparison tests. Results: Utilizing 3D digitized and injection-derived volumes and dimensions, anterior dog ear volume, height, and width were significantly smaller for rotator cuff repair with peripheral looped sutures compared with a suture bridge (P < .05) or double-row repair with 2-mm fiber tape alone (P < .05). Similarly, posterior height and width were significantly smaller for repair with looped peripheral sutures compared with a suture bridge (P < .05). Dog ear volumes and heights trended larger for the 1.5-cm tear, but this was not statistically significant

  2. 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.

  3. Ruptures of the distal biceps tendon.

    PubMed

    Ward, James P; Shreve, Mark C; Youm, Thomas; Strauss, Eric J

    2014-01-01

    Distal biceps ruptures occur most commonly in middle-aged males and result from eccentric contraction of the biceps tendon. The injury typically presents with pain and a tearing sensation in the antecubital fossa with resultant weakness in flexion and supination strength. Physical exam maneuvers and diagnostic imaging aid in determining the diagnosis. Nonoperative management is reserved for elderly, low demand patients, while operative intervention is generally pursued for younger patients and can consist of nonanatomic repair to the brachialis or anatomic repair to the radial tuberosity. Anatomic repair through a one-incision or two-incision approach is commonplace, while the nonanatomic repairs are rarely performed. No clear advantage exists in operative management with a one-incision versus two-incision techniques. Chronic ruptures present a more difficult situation, and allograft augmentation is often necessary. Common complications after repair include transient nerve palsy, which often resolves, and heterotopic ossification. Despite these possible complications, most studies suggest that better patient outcomes are obtained with operative, anatomic reattachment of the distal biceps tendon.

  4. Steroid injections - tendon, bursa, joint

    MedlinePlus

    ... ency/article/007678.htm Steroid injections - tendon, bursa, joint To use the sharing features on this page, ... often painful. It can be injected into a joint, tendon, or bursa. Description Your health care provider ...

  5. Tendon Driven Finger Actuation System

    NASA Technical Reports Server (NTRS)

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

    2013-01-01

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

  6. 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.

  7. Neuronal regulation of tendon homoeostasis

    PubMed Central

    Ackermann, Paul W

    2013-01-01

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

  8. Biomechanical Study of Two Peripheral Suture Methods on Repaired Tendons

    PubMed Central

    Qiu, Zhenling

    2015-01-01

    Flexor digitorum tendon injuries are challenging conditions to manage to ensure optimal patient outcomes. While several surgical approaches with high success rates have been developed, there remains no gold standard for suture technique for the repair of flexor tendon injuries. In this study, we compared two distinct peripheral suture methods on the strength of repaired tendons. Pig flexor digitorum profundus tendons were used in biomechanical studies and the biomechanical influence on tendon repair of continuous running peripheral suture (CRPS) and continuous locking peripheral suture (CLPS), were compared, using stitch length ranging from 1mm to 5mm. In CRPS, the 1mm stitch length group displayed the highest maximum load and breaking power, which was 1.57 fold higher than the 2mm stitch length group. Pairwise comparison revealed that the 1 and 2mm groups were statistically different from the 3, 4, and 5mm stitch length groups while comparison among the latter groups was not statistically significant. For CLPS, the 1mm group exhibited consistently the highest maximum load strength and breaking power, which was twice the strength displayed by the 2mm group. Pairwise comparisons between groups showed statistical significance. For future repairs of flexor tendon injuries, 1mm stitch length is highly recommended for simple peripheral suture.

  9. Radial tears of the menisci: MR findings.

    PubMed

    Tuckman, G A; Miller, W J; Remo, J W; Fritts, H M; Rozansky, M I

    1994-08-01

    Radial meniscal tears have a plane of cleavage oriented across the short axis of the meniscus in the same plane in which radial images are oriented. These tears are important to recognize, because they have clinical implications different from those of other meniscal tears with respect to meniscal function, orthopedic treatment, and clinical course. Depending on their size, location, and orientation, radial tears can have different appearances on standard MR images. Certain types can be fairly subtle to diagnose. The purpose of this essay is to illustrate the varied appearances of radial tears on MR images and the findings commonly associated with radial tears.

  10. 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.

  11. Wear and Tear - Mechanical

    NASA Technical Reports Server (NTRS)

    Swanson, Theodore

    2008-01-01

    The focus of this chapter is on the long term wear and tear, or aging, of the mechanical subsystem of a spacecraft. The mechanical subsystem is herein considered to be the primary support structure (as in a skeleton or exoskeleton) upon which all other spacecraft systems rest, and the associated mechanisms. Mechanisms are devices which have some component that moves at least once, in response to some type of passive or active control system. For the structure, aging may proceed as a gradual degradation of mechanical properties and/or function, possibly leading to complete structural failure over an extended period of time. However, over the 50 years of the Space Age such failures appear to be unusual. In contrast, failures for mechanisms are much more frequent and may have a very serious effect on mission performance. Just as on Earth, all moving devices are subject to normal (and possibly accelerated) degradation from mechanical wear due to loss or breakdown of lubricant, misalignment, temperature cycling effects, improper design/selection of materials, fatigue, and a variety of other effects. In space, such environmental factors as severe temperature swings (possibly 100's of degrees C while going in and out of direct solar exposure), hard vacuum, micrometeoroids, wear from operation in a dusty or contaminated environment, and materials degradation from radiation can be much worse. In addition, there are some ground handling issues such as humidity, long term storage, and ground transport which may be of concern. This chapter addresses the elements of the mechanical subsystem subject to wear, and identifies possible causes. The potential impact of such degradation is addressed, albeit with the recognition that the impact of such wear often depends on when it occurs and on what specific components. Most structural elements of the mechanical system typically are conservatively designed (often to a safety factor of greater than approximately 1.25 on yield for

  12. Rabbit supraspinatus motor endplates are unaffected by a rotator cuff tear.

    PubMed

    Gayton, J Christopher; Rubino, L Joseph; Rich, Mark M; Stouffer, Mark H; Wang, Qingbo; Boivin, Gregory P

    2013-01-01

    Rotator cuff tears are a major cause of morbidity. Following rotator cuff tears, muscle atrophy and fatty infiltration begin in the tissue, limiting repair potential and leading to a higher re-tear rate and a worse functional outcome. We evaluated whether fatty degeneration resulting from a complete supraspinatus tear with retraction is associated with an injury to the suprascapular nerve. Four skeletally mature New Zealand white rabbits were randomized to receive an index procedure on either their right or left shoulder with the opposite shoulder serving as a control. At the index procedure, the supraspinatus tendon was transected at its insertion and allowed to retract. At 3 months, the rabbits were euthanized, and both supraspinatus muscles were harvested. The specimens were then examined with confocal microscopy and histology. Atrophy was grossly visible in all four test muscles, and fatty infiltration was confirmed with osmium tetroxide staining. In all four rabbits, the degree of denervation (p = 0.71) and partial denervation (p = 0.91) was not significantly different between control and experimental muscle. Rotator cuff tear does not affect the motor endplate or innervation status of the supraspinatus. Fatty infiltration occurs independent of denervation of the supraspinatus.

  13. Tear exchange and contact lenses: a review.

    PubMed

    Muntz, Alex; Subbaraman, Lakshman N; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses.

  14. Tear exchange and contact lenses: A review

    PubMed Central

    Muntz, Alex; Subbaraman, Lakshman N.; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. PMID:25575892

  15. Clinico-Radiological Correlation of Subcoracoid Impingement with Reduced Coracohumeral Interval and its Relation to Subscapularis Tears in Indian Patients

    PubMed Central

    Rao, Srivatsa Nagaraja; Kumaran, Chandrababu Kadassery; Kochukunju, Bhaskaran Vadakkekottu

    2016-01-01

    Introduction Clinically, subcoracoid impingement is characterized by pain at the anterior aspect of the shoulder that is induced by adduction, internal rotation and forward flexion. This position leads to narrowing of the Coraco-Humeral Interval (CHI)-that is, the space between the coracoid process and the lesser tuberosity of the humerus. Structures in the rotator interval are at greatest risk for impingement which includes the Subscorapularis tendon, tendon of the long head of the biceps, and the middle gleno-humeral ligament. This may result in Rotator interval pathologies such as subscapularis tear and long head of biceps tendon subluxation or fraying. Aim To study the prevalence of radiological evidence of reduced Coraco-Humeral Interval (CHI) in patients with clinically evident Subcoracoid impingement and to examine the presence of Subscapularis tears in these patients. Materials and Methods Twenty four patients (6 males, 18 females, average age 52.83 years) were included in this prospective study who were diagnosed to have rotator cuff tears clinically. Nine of these patients were clinically found to have concomitant subcracoid impingement. All patients were subjected to MRI of shoulder. Measurement of the CHI was done in images with humerus in maximal internal rotation. Presence of subscapularis tear was examined intraoperatively. Statistical evaluation of the data was performed using Student’s t-test and Fisher’s exact test and the results were applied to two cohorts of patients. One cohort consisted of patients who had a CHI value of less than 5.5mm and the other cohort had a CHI value greater than 5.5mm. Average CHI values in patients with and without a subscapularis tear were determined. Results Nine patients who had clinical subcoracoid impingement were found to have an average CHI of 5.33mm. All nine of them had an associated tear of subscapularis with long head of Biceps tendon subluxation and/or fraying. Remaining 15 patients had an average CHI

  16. Tendon injuries of the hand

    PubMed Central

    Schöffl, Volker; Heid, Andreas; Küpper, Thomas

    2012-01-01

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

  17. Mineral Distributions at the Developing Tendon Enthesis

    PubMed Central

    Schwartz, Andrea G.; Pasteris, Jill D.; Genin, Guy M.; Daulton, Tyrone L.; Thomopoulos, Stavros

    2012-01-01

    Tendon attaches to bone across a functionally graded interface, “the enthesis”. A gradient of mineral content is believed to play an important role for dissipation of stress concentrations at mature fibrocartilaginous interfaces. Surgical repair of injured tendon to bone often fails, suggesting that the enthesis does not regenerate in a healing setting. Understanding the development and the micro/nano-meter structure of this unique interface may provide novel insights for the improvement of repair strategies. This study monitored the development of transitional tissue at the murine supraspinatus tendon enthesis, which begins postnatally and is completed by postnatal day 28. The micrometer-scale distribution of mineral across the developing enthesis was studied by X-ray micro-computed tomography and Raman microprobe spectroscopy. Analyzed regions were identified and further studied by histomorphometry. The nanometer-scale distribution of mineral and collagen fibrils at the developing interface was studied using transmission electron microscopy (TEM). A zone (∼20 µm) exhibiting a gradient in mineral relative to collagen was detected at the leading edge of the hard-soft tissue interface as early as postnatal day 7. Nanocharacterization by TEM suggested that this mineral gradient arose from intrinsic surface roughness on the scale of tens of nanometers at the mineralized front. Microcomputed tomography measurements indicated increases in bone mineral density with time. Raman spectroscopy measurements revealed that the mineral-to-collagen ratio on the mineralized side of the interface was constant throughout postnatal development. An increase in the carbonate concentration of the apatite mineral phase over time suggested possible matrix remodeling during postnatal development. Comparison of Raman-based observations of localized mineral content with histomorphological features indicated that development of the graded mineralized interface is linked to endochondral

  18. Mineral distributions at the developing tendon enthesis.

    PubMed

    Schwartz, Andrea G; Pasteris, Jill D; Genin, Guy M; Daulton, Tyrone L; Thomopoulos, Stavros

    2012-01-01

    Tendon attaches to bone across a functionally graded interface, "the enthesis". A gradient of mineral content is believed to play an important role for dissipation of stress concentrations at mature fibrocartilaginous interfaces. Surgical repair of injured tendon to bone often fails, suggesting that the enthesis does not regenerate in a healing setting. Understanding the development and the micro/nano-meter structure of this unique interface may provide novel insights for the improvement of repair strategies. This study monitored the development of transitional tissue at the murine supraspinatus tendon enthesis, which begins postnatally and is completed by postnatal day 28. The micrometer-scale distribution of mineral across the developing enthesis was studied by X-ray micro-computed tomography and Raman microprobe spectroscopy. Analyzed regions were identified and further studied by histomorphometry. The nanometer-scale distribution of mineral and collagen fibrils at the developing interface was studied using transmission electron microscopy (TEM). A zone (∼20 µm) exhibiting a gradient in mineral relative to collagen was detected at the leading edge of the hard-soft tissue interface as early as postnatal day 7. Nanocharacterization by TEM suggested that this mineral gradient arose from intrinsic surface roughness on the scale of tens of nanometers at the mineralized front. Microcomputed tomography measurements indicated increases in bone mineral density with time. Raman spectroscopy measurements revealed that the mineral-to-collagen ratio on the mineralized side of the interface was constant throughout postnatal development. An increase in the carbonate concentration of the apatite mineral phase over time suggested possible matrix remodeling during postnatal development. Comparison of Raman-based observations of localized mineral content with histomorphological features indicated that development of the graded mineralized interface is linked to endochondral

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

    PubMed

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

    2015-01-01

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

  20. Ligamentum teres tendinopathy and tears

    PubMed Central

    Kraeutler, Matthew J.; Garabekyan, Tigran; Pascual-Garrido, Cecilia; Mei-Dan, Omer

    2016-01-01

    Summary Background The ligamentum teres (LT) consists of two bands that originate on the ischial and pubic sides of the acetabular notch and insert on the fovea capitis of the femoral head. Recent studies have established the LT as an important hip stabilizer in a squatting position, particularly in patients with osseous instability. Purpose This review aims to concisely present the literature on LT tendinopathy and tears in order to guide health care professionals in the appropriate diagnosis and treatment of these disorders. Methods We reviewed the literature on the diagnosis and surgical management of ligamentum teres tendinopathy and tears. Conclusions The ligamentum teres is an important stabilizer to the hip joint, particularly with hip flexion and external rotation. Older age and acetabular bony pathomorphology are two of the known risk factors for LT tears. Symptoms of LT tendinopathy are largely non-specific, mimicking a wide range of other hip disorders including impingement and instability. Debridement of LT tears or reactive tissue has been reported with good outcomes, with more recent studies describing reconstruction of a completely torn, nonfunctional, or absent LT using various graft sources including synthetic grafts, autografts, and allografts. Level of evidence II. PMID:28066738

  1. Investigation of spherical tearing mode

    NASA Technical Reports Server (NTRS)

    Greene, John M.; Miller, R. L.

    1995-01-01

    The purpose of this research was to better understand tearing and reconnection in genuinely three-dimensional configurations. We have identified an equilibrium model that should contain the required features. Three papers have been written and a fourth is in preparation. They are listed in the bibliography.

  2. 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

  3. Parameters influencing prevalence and outcome of tendonitis in Thoroughbred and Arabian racehorses.

    PubMed

    Kalisiak, O

    2012-01-01

    Flexor tendonitis and suspensory desmitis are among most prevalent musculoskeletal injuries observed in racehorses. The aim of this study was to determine which horse and race-related parameters can help to diminish the possibility of injury or--when injury has occurred--to evaluate the potential for the horse to continue a successful career after convalescence. Special attention was given to the comparison of Arabian and Thoroughbred racehorses. 187 horses with ultrasonographically visible lesions were included in the study. Following parameters were analyzed: structure (Superficial Digital Flexor Tendon [SDFT], Deep Digital Flexor Tendon [DDFT], Suspensory Ligament [SL]); percentage of cross sectional area increase; hypoechogenic lesion character; in horses with SDF tendonitis - tendonitis grade according to Genovese. This study showed that Thoroughbreds are more at risk of musculoskeletal problems than Arabian racehorses. In both breeds, the most frequent injuries concern SDFT, then SL. Over 95% of tendonitis concern forelimbs. In Thoroughbreds, the prevalence of tendonitis is higher in bigger horses, in males when compared to females and in fence/steeple racehorses when compared to flat track racehorses. The inside limb is more at risk of SDF tendonitis, when the external limb - of SL desmitis. Tendonitis severity increases with age and is greater in steeplechasers when compared to flat track racehorses. The outcome of tendonitis without hypoechogenic lesion is much better than that with hypoechogenic lesion. Evaluation of hypoechogenic lesion length is an easy and accurate prognosis tool, as the chances of returning to racing drop dramatically with lesions longer than 12 cm.

  4. 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

  5. Lateral column lengthening for acquired adult flatfoot deformity caused by posterior tibial tendon dysfunction stage II: a retrospective comparison of calcaneus osteotomy with calcaneocuboid distraction arthrodesis.

    PubMed

    Haeseker, Guus A; Mureau, Marc A; Faber, Frank W M

    2010-01-01

    In this study, clinical and radiological results after lateral column lengthening by calcaneocuboid distraction arthrodesis and calcaneus osteotomy were compared. Thirty-three patients (35 feet) treated with lateral column lengthening by distraction arthrodesis (14 patients, 16 feet; group I) or by calcaneus osteotomy (19 patients, 19 feet; group II) for adult-acquired flatfoot deformity caused by stage II posterior tibial tendon dysfunction were compared retrospectively. Mean follow-up was 42.4 months (range, 6-78 months) for group I and 15.8 months (range, 6-32 months) for group II (P < .001). The American Orthopaedic Foot & Ankle Society ankle-hindfoot score was determined, 4 variables were measured on preoperative and postoperative weight-bearing radiographs, and a number of independent and outcome variables, including patient satisfaction, were recorded. Group 2 had a significantly higher American Orthopaedic Foot & Ankle Society score compared with group I (mean, 85 vs. 72, respectively; P < .02) at time of last follow-up, and there were no dissatisfied patients in group I, whereas 2 patients in group II were dissatisfied with the result of the operation. All radiological results were significantly better at time of follow-up in both groups (except for talocalcaneal angle in group I), although no significant differences were noted in the amount of change in radiographic measurements between the groups. No significant correlation was found between follow-up time and radiographic improvement, indicating stable radiographic measurements over time. In group II, 13 mild calcaneocuboid subluxations were observed. In both groups, 1 nonunion and 1 wound complication occurred. Based on our experience with the patients described in this report, we recommend lateral column lengthening by means of calcaneus osteotomy rather than distraction arthrodesis of the calcaneocuboid joint, for correction of stage II posterior tibial tendon dysfunction.

  6. Single-Versus Double-Row Arthroscopic Rotator Cuff Repair in Massive Tears

    PubMed Central

    Wang, EnZhi; Wang, Liang; Gao, Peng; Li, ZhongJi; Zhou, Xiao; Wang, SongGang

    2015-01-01

    Background It is a challenge for orthopaedic surgeons to treat massive rotator cuff tears. The optimal management of massive rotator cuff tears remains controversial. Therefore, the goal of this study was to compare arthroscopic single- versus double-row rotator cuff repair with a larger sample size. Material/Methods Of the subjects with massive rotator cuff tears, 146 were treated using single-row repair, and 102 were treated using double-row repair. Pre- and postoperative functional outcomes and radiographic images were collected. The clinical outcomes were evaluated for a minimum of 2 years. Results No significant differences were shown between the groups in terms of functional outcomes. Regarding the integrity of the tendon, a lower rate of post-treatment retear was observed in patients who underwent double-row repair compared with single-row repair. Conclusions The results suggest that double-row repair is relatively superior in shoulder ROM and the strength of tendon compared with single-row repair. Future studies involving more patients in better-designed randomized controlled trials will be required. PMID:26017641

  7. 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

    statistically significant differences. The result of the total excellent and good rate was 93.8% (30/32). MRI of Achilles tendon showed even signal without evidence of tear or cystic degeneration. Conclusion: Reconstruction of a chronic Achilles tendon rupture with an FHL tendon harvested using a minimally invasive technique showed good outcomes. PMID:27746496

  8. Effect of overuse-induced tendinopathy on tendon healing in a rat supraspinatus repair model.

    PubMed

    Tucker, Jennica J; Riggin, Corinne N; Connizzo, Brianne K; Mauck, Robert L; Steinberg, David R; Kuntz, Andrew F; Soslowsky, Louis J; Bernstein, Joseph

    2016-01-01

    Supraspinatus tears often result in the setting of chronic tendinopathy. However, the typical repair model utilizes an acute injury. In recognition of that distinction, our laboratory developed an overuse animal model; however it is unclear whether induced overuse is necessary in the repair model. We studied the repair properties of overuse-induced tendons compared to normal tendons. We hypothesized that histological and mechanical properties would not be altered between the overuse-induced and normal tendons 1 and 4 weeks after repair. Thirty-one adult male Sprague-Dawley rats were subjected to either overuse or cage activity for 4 weeks prior to bilateral supraspinatus tendon repair surgery. Rats were sacrificed at 1 and 4 weeks post-surgery and evaluated for histology and mechanics. Results at 1 week showed no clear histologic changes, but increased inflammatory protein expression in overuse tendons. At 4 weeks, percent relaxation was slightly increased in the overuse group. No other alterations in mechanics or histology were observed. Our results suggest that the effects of the surgical injury overshadow the changes evoked by overuse. Because clinically relevant mechanical parameters were not altered in the overuse group, we conclude that when examining tendons 4 weeks after repair in the classic rat supraspinatus model, inducing overuse prior to surgery is likely to be unnecessary.

  9. Achilles tendon injuries in athletes.

    PubMed

    Kvist, M

    1994-09-01

    Two-thirds of Achilles tendon injuries in competitive athletes are paratenonitis and one-fifth are insertional complaints (bursitis and insertion tendinitis). The remaining afflictions consist of pain syndromes of the myotendineal junction and tendinopathies. The majority of Achilles tendon injuries from sport occur in males, mainly because of their higher rates of participation in sport, but also with tendinopathies a gender difference is probably indicated. Athletes in running sports have a high incidence of Achilles tendon overuse injuries. About 75% of total and the majority of partial tendon ruptures are related to sports activities usually involving abrupt repetitive jumping and sprinting movements. Mechanical factors and a sedentary lifestyle play a role in the pathology of these injuries. Achilles tendon overuse injuries occur at a higher rate in older athletes than most other typical overuse injuries. Recreational athletes with a complete Achilles tendon rupture are about 15 years younger than those with other spontaneous tendon ruptures. Following surgery, about 70 to 90% of athletes have a successful comeback after Achilles tendon injury. Surgery is required in about 25% of athletes with Achilles tendon overuse injuries and the frequency of surgery increases with patient age and duration of symptoms as well as occurrence of tendinopathic changes. However, about 20% of injured athletes require a re-operation for Achilles tendon overuse injuries, and about 3 to 5% are compelled to abandon their sports career because of these injuries. Myotendineal junction pain should be treated conservatively. Partial Achilles tendon ruptures are primarily treated conservatively, although the best treatment method of chronic partial rupture seems to be surgery. Complete Achilles tendon ruptures of athletes are treated surgically, because this increases the likelihood of athletes reaching preinjury activity levels and minimises the risk of re-ruptures. Marked forefoot

  10. Development of a mouse model of supraspinatus tendon insertion site healing.

    PubMed

    Bell, Rebecca; Taub, Peter; Cagle, Paul; Flatow, Evan L; Andarawis-Puri, Nelly

    2015-01-01

    Supraspinatus (SS) tendon tears are common musculoskeletal injuries whose surgical repair exhibits the highest incidence of re-tear of any tendon. Development of therapeutics for improving SS tendon healing is impaired by the lack of a model that allows biological perturbations to identify mechanisms that underlie ineffective healing. The objective of this study was to develop a mouse model of supraspinatus insertion site healing by creating a reproducible SS tendon detachment and surgical repair which can be applied to a wide array of inbred mouse strains and genetic mutants. Anatomical and structural analyses confirmed that the rotator cuff of the mouse is similar to that of human, including the presence of a coracoacromial (CA) arch and an insertion site that exhibits a fibrocartilagenous transition zone. The surgical repair was successfully conducted on seven strains of mice that are commonly used in Orthopaedic Research suggesting that the procedure can be applied to most inbred strains and genetic mutants. The quality of the repair was confirmed with histology through 14 days after surgery in two mouse strains that represent the variation in mouse strains evaluated. The developed mouse model will allow us to investigate mechanisms involved in insertion site healing.

  11. Rat rotator cuff muscle responds differently from hindlimb muscle to a combined tendon-nerve injury.

    PubMed

    Davies, Michael R; Ravishankar, Bharat; Laron, Dominique; Kim, Hubert T; Liu, Xuhui; Feeley, Brian T

    2015-07-01

    Rotator cuff tears (RCTs) are among the most common musculoskeletal injuries seen by orthopaedic surgeons. Clinically, massive cuff tears lead to unique pathophysiological changes in rotator cuff muscle, including atrophy, and massive fatty infiltration, which are rarely seen in other skeletal muscles. Studies in a rodent model for RCT have demonstrated that these histologic findings are accompanied by activation of the Akt/mammalian target of rapamycin (mTOR) and transforming growth factor-β (TGF-β) pathways following combined tendon-nerve injury. The purpose of this study was to compare the histologic and molecular features of rotator cuff muscle and gastrocnemius muscle--a major hindlimb muscle, following combined tendon-nerve injury. Six weeks after injury, the rat gastrocnemius did not exhibit notable fatty infiltration compared to the rotator cuff. Likewise, the adipogenic markers SREBP-1 and PPARγ as well as the TGF-β canonical pathway were upregulated in the rotator cuff, but not the gastrocnemius. Our study suggests that the rat rotator cuff and hindlimb muscles differ significantly in their response to a combined tendon-nerve injury. Clinically, these findings highlight the unique response of the rotator cuff to injury, and may begin to explain the poor outcomes of massive RCTs compared to other muscle-tendon injuries.

  12. Comparison of Transverse Intraosseous Loop Technique and Pull Out Suture for Reinsertion of the Flexor Digitorum Profundus tendon. A Retrospective Study.

    PubMed

    Rigó, István Zoltán; Røkkum, Magne

    2013-12-01

    We compared the results of two methods for reinsertion of flexor digitorum profundus tendons retrospectively. In 35 fingers of 29 patients pull-out suture and in 13 fingers of 11 patients transverse intraosseous loop technique was performed with a mean follow-up of 8 and 6 months, respectively. Eleven and nine fingers achieved "excellent" or "good" function according to Strickland and Glogovac at 8 weeks; 20 and ten at the last control in the pull-out and transverse intraosseous loop groups, respectively. The difference at 8 weeks was statistically significant in favour of the transverse intraosseous loop group. Ten patients underwent 12 complications in the pull-out group (four superficial infections; one rerupture, one PIP and one DIP joint contracture, one adhesion, two granulomas, one nail deformity and one carpal tunnel syndrome) and four of them were reoperated (one carpal tunnel release, one teno-arthrolysis and two resections of granuloma). There was no complication and no reoperation in the transverse intraosseous loop group, the difference being statistically significant for the former. In our study the transverse intraosseous loop technique seemed to be a safe alternative with possibly better functional results compared to the pull-out suture.

  13. Assessment of dorsal instability of the ulnar head in the distal radioulnar joint: comparison between normal wrist joints and cases of ruptured extensor tendons.

    PubMed

    Naito, Kiyohito; Sugiyama, Yoichi; Aritomi, Kentaro; Nagahama, Yasushi; Tomita, Yoshimasa; Obayashi, Osamu; Kaneko, Kazuo

    2016-02-01

    In the present study, the adaptability of the distal radioulnar joint (DRUJ) was evaluated using conventional computed tomography (CT) evaluation methods. In addition, we investigated/compared a new method to evaluate dorsal displacement of the ulnar head. Our subjects consisted of 32 healthy volunteers (64 wrists) and 11 patients (13 wrists) with extensor tendon injuries related to dorsal displacement of the ulnar head. To diagnose instability in the DRUJ based on CT scans, the radioulnar line method and the modified radioulnar line method were measured. Instability was evaluated by the new method that the ulnar head was located on the dorsal side from a line involving the peak of Lister's tubercle in parallel to this baseline was regarded as showing abnormal dorsal displacement of the ulnar head. The diagnostic accuracy of each method was calculated. The sensitivities, specificities, false-positive rates, positive predictive values and the negative predictive value of new methods were better than other two methods. The new method that we recommend is simple. Based on the results of this study, an evaluation of normal/abnormal dorsal displacement of the ulnar head in the DRUJ using the new method may be useful for determining the timing of surgery.

  14. Vitamin D in Tear Fluid

    PubMed Central

    Lu, Xiaowen; Elizondo, Rodolfo A.; Nielsen, Rikke; Christensen, Erik I.; Yang, Jun; Hammock, Bruce D.; Watsky, Mitchell A.

    2015-01-01

    Purpose To determine the source(s) of vitamin D in tear fluid and examine the expression of the endocytic proteins and putative vitamin D transporters megalin and cubilin in lacrimal and Harderian glands. Methods Wild-type, heterozygous, and vitamin D receptor (VDR) knockout C57BL/6 mice were used, with a subset of knockout mice fed a replenishment diet for some studies. Mouse lacrimal and Harderian glands from each group were used to measure megalin and cubilin by RT-PCR, Western blot, and immunohistochemistry. New Zealand white rabbits were used to collect lacrimal and accessory gland fluid for vitamin D mass spectroscopy measurements. Results Ten-week-old knockout mice were significantly (P < 0.05) smaller than wild-type mice. Real-time PCR and Western blot showed decreased expression of megalin and cubilin in select VDR knockout mouse groups. Immunohistochemistry showed apical duct cell megalin staining and weaker megalin staining in VDR knockout mice compared with controls. Vitamin D2 was more prevalent in rabbit lacrimal and accessory gland fluid than vitamin D3, and greater amounts of Vitamin D2 were found in in tear fluid obtained directly from lacrimal and accessory glands as compared with plasma concentrations. Conclusions This is the first study to demonstrate the presence of megalin and cubilin in lacrimal and accessory glands responsible for producing tear fluid. The results strengthen the hypothesis that megalin and cubilin are likely involved in the secretory pathway of vitamin D into tear fluid by the duct cells. PMID:26348637

  15. Tear analysis in contact lens wearers.

    PubMed Central

    Farris, R L

    1985-01-01

    Tear analysis in contact lens wearers was compared with tear analysis in aphakics without contact lens wear and normal phakic patients. Subjects were divided into five groups: group 1, aphakic without contact lens; group 2, phakic with daily-wear hard contact lens; group 3, phakic with daily-wear soft contact lens; group 4, phakic with extended-wear soft contact lens; and group 5, aphakic with extended-wear soft contact lens. The experimental groups were compared with age- and sex-matched control groups for statistical analysis of tear variables by means of the Student's t-test. The variables measured were tear osmolarity, tear albumin, and lysozyme and lactoferrin concentrations in basal and reflex tears. Highly significant elevations of tear osmolarity were found in aphakic subjects without contact lenses. Less significant differences in tear osmolarity were found in phakic subjects with hard daily-wear lenses or with extended-wear soft lenses. Tear albumin, lysozyme, and lactoferrin in basal and reflex tears were not significantly different in the different groups of contact lens wearers or in the group of aphakic subjects without contact lenses compared with their control groups. Individual variations in tear albumin, lysozyme, and lactoferrin appeared to be responsible for the inability to demonstrate significant differences in tear composition in association with the wearing of different types of contact lenses. Older and aphakic patients demonstrated a tendency to have increased concentrations of proteins in the tears compared with younger, phakic contact lens wearers and normal controls without contact lenses. PMID:3914131

  16. Current evidence for effectiveness of interventions to treat rotator cuff tears.

    PubMed

    Huisstede, Bionka M A; Koes, Bart W; Gebremariam, Lukas; Keijsers, Ellen; Verhaar, Jan A N

    2011-06-01

    In this systematic review we assessed effectiveness of non-surgical and (post)surgical interventions for symptomatic rotator cuff tears (RotCuffTear). The Cochrane Library, PubMed, Embase, Cinahl, and Pedro were searched for relevant systematic reviews and randomized controlled trials (RCTs). Two reviewers independently selected relevant studies, extracted data and assessed the methodological quality. Three Cochrane reviews (7 RCTs) and 14 RCTs were included (3 non-surgery, 10 surgery, 8 post-surgery). For small or medium RotCufftears, moderate evidence was found in favour of surgery versus physiotherapy in mid- and long-term. In surgery, tendon-to-bone fixation with one metal suture anchor loaded with double sutures (TB) was more effective (moderate evidence) than a side-to-side repair with permanent sutures (SS) in the mid- and long-term; limited evidence for effectiveness was found in favour of debridement versus anchor replacement and suture repair of the type II SLAP tear in the long-term. Further, no evidence was found in favour of any non-surgical, surgical or post-surgical intervention. In conclusion, although surgery seems to give better results compared to non-surgery and TB is more effective than SS in rotator cuff repair (RCR), it remains hard to draw firm evidence-based conclusions for effectiveness of non-surgical or (post)surgical interventions to treat RotCuffTears. More research is clearly needed.

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

    PubMed Central

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

    2015-01-01

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

  18. Observation of tendon repair in animal model using second-harmonic-generation microscopy

    NASA Astrophysics Data System (ADS)

    Hase, Eiji; Minamikawa, Takeo; Sato, Katsuya; Takahashi, Mitsuhiko; Yasui, Takashi

    2016-03-01

    Tendon rupture is a trauma difficult to recover the condition before injury. In previous researches, tensile test and staining method have been widely used to elucidate the mechanism of the repair process from the viewpoints of the mechanical property and the histological findings. However, since both methods are destructive and invasive, it is difficult to obtain both of them for the same sample. If both the mechanical property and the histological findings can be obtained from the same sample, one may obtain new findings regarding mechanisms of tendon repairing process. In this paper, we used second-harmonic-generation (SHG) microscopy, showing high selectivity and good image contrast to collagen molecules as well as high spatial resolution, optical three-dimensional sectioning, deep penetration, and without additional staining. Since SHG light intensity sensitively reflects the structural maturity of collagen molecule and its aggregates, it will be a good indicator for the repairing degree of the ruptured tendon. From comparison of SHG images between the 4-weeks-repaired tendon and the sound tendon in the animal model, we confirmed that SHG light intensity of the repaired tendon was significantly lower than that of the sound tendon, indicating that the collagen structure in the repaired tendon is still immature. Furthermore, we performed both SHG imaging and the tensile test for the same sample, and confirmed a correlation between them. This result shows a potential of SHG light for an indicator of the histological and mechanical recovery of the ruptured tendon.

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

    PubMed

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

    2015-06-01

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

  20. Glenoid labrum tears related to the long head of the biceps.

    PubMed

    Andrews, J R; Carson, W G; McLeod, W D

    1985-01-01

    Tears of the glenoid labrum were observed in 73 baseball pitchers and other throwing athletes who underwent arthroscopic examination of the dominant shoulder. Most of the tears were located over the anterosuperior portion of the glenoid labrum near the origin of the tendon of the long head of the biceps muscle into the glenoid. At arthroscopy, the tendon of the long head of the biceps appeared to originate through and be continuous with the superior portion of the glenoid labrum. In many cases it appeared to have pulled the anterosuperior portion of the labrum off the glenoid. This observation was verified at arthroscopy by viewing the origin of the biceps tendon into the glenoid labrum as the muscle was electrically stimulated. With stimulation of the muscle, the tendinous portion became quite taut, particularly near its attachment to the glenoid labrum, and actually lifted the labrum off the glenoid. Three-dimensional high-speed cinematography with computer analysis revealed that the moment acting about the elbow joint to extend the joint through an arc of about 50 degrees was in excess of 600 inch-pounds. The extremely high velocity of elbow extension which is generated must be decelerated through the final 30 degrees of elbow extension. Of the muscles of the arm that provide the large deceleration forces in the follow-through phase of throwing, only the biceps brachii traverses both the elbow joint and the shoulder joint. Additional forces are generated in the biceps tendon in its function as a "shunt" muscle to stabilize the glenohumeral joint during the throwing act.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. 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

  2. Tear rotation in reinforced natural rubber

    NASA Astrophysics Data System (ADS)

    Sotta, Paul; Gabrielle, Brice; Vieyres, Arnaud; Vanel, Loic; Long, Didier; Sanseau, Olivier; Albouy, Pierre-Antoine

    2012-02-01

    We analyze the impact of tear rotation, that is, an abrupt instability in the direction of propagation of a notch, on the tensile strength of natural rubber elastomers reinforced with carbon black or precipitated silica, in single edge notched samples stretched at constant velocity. As a consequence of tear rotation, the energy at break increases by a factor of 6 to 8 in some cases. We show how the tensile strength of a test sample is related to the presence of tear rotations and analyze semi-quantitatively this increase in tensile strength, based on energetic arguments, without entering into a detailed description of the elastic strain field in the vicinity of the tear tip. The proposed interpretation is based on the idea that tear rotations creates a macroscopic tip radius, which relaxes the local strain (or stress) at the tear tip. Materials reinforced with carbon black or precipitated silica aggregates show similar behavior. The relation to strain-induced crystallization is discussed.

  3. The role of stretching in tendon injuries.

    PubMed

    Witvrouw, E; Mahieu, N; Roosen, P; McNair, P

    2007-04-01

    The function of tendons can be classified into two categories: tensile force transmission, and storage and release of elastic energy during locomotion. The action of tendons in storing and releasing energy is mainly seen in sports activities with stretch-shortening cycles (SSCs). The more intense the SSC movements are (jumping-like activities), the more frequently tendon problems are observed. High SSC movements impose high loads on tendons. Consequently, tendons that frequently deal with high SSC motion require a high energy-absorbing capacity to store and release this large amount of elastic energy. As the elasticity of tendon structures is a leading factor in the amount of stored energy, prevention and rehabilitation programmes for tendon injuries should focus on increasing this tendon elasticity in athletes performing high SSC movements. Recently, it has been shown that ballistic stretching can significantly increase tendon elasticity. These findings have important clinical implications for treatment and prevention of tendon injuries.

  4. A Special Tear Pattern of Anterior Horn of the Lateral Meniscus: Macerated Tear

    PubMed Central

    Zheng, Jiapeng; Zhai, Wenliang; Li, Qiang; Jia, Qianxin

    2017-01-01

    Background We describe a special, interesting phenomenon found in the anterior horn of the lateral meniscus (AHLM): most tear patterns in the AHLM are distinctive, with loose fibers in injured region and circumferential fiber bundles were separated. We name it as macerated tear. The goal of this study was to bring forward a new type of meniscal tear in the AHLM and investigate its clinical value. Materials and Methods AHLM tears underwent arthroscopic surgery from January 2012 to December 2014 were included. Data regarding the integrity of AHLM were prospectively recorded in a data registry. Tear morphology and treatment received were subsequently extracted by 2 independent reviewers from operative notes and arthroscopic surgical photos. Results A total of 60 AHLM tears in 60 patients (mean age 27.1 years) were grouped into horizontal tears (n = 15, 25%), vertical tears (n = 14, 23%), complex tears (n = 6, 10%), and macerated tears (n = 25, 42%). There were 6 patients with AHLM cysts in macerated tear group and one patient in vertical tear group. 60 patients were performed arthroscopic meniscus repairs and were followed-up with averaged 18.7 months. Each group had significant postoperative improvement in Lysholm and IKDC scores (p < 0.05). However, the macerated tear group showed least functional recovery of Lysholm and IKDC scores compared to other groups (p < 0.05). In addition, there were no differences in postoperative range of motion, return to work, or return to sport/other baseline activities between the four groups (p > 0.05). Conclusions This study demonstrated that the macerated tear is common in the tear pattern of AHLM. However, feasibility of the treatment of this type of meniscal tear, especially the meniscus repairs still requires further study. PMID:28125675

  5. Simultaneous bilateral patellar tendon rupture.

    PubMed

    Moura, Diogo Lino; Marques, José Pedro; Lucas, Francisco Manuel; Fonseca, Fernando Pereira

    2017-01-01

    Bilateral patellar tendon rupture is a rare entity, often associated with systemic diseases and patellar tendinopathy. The authors report a rare case of a 34-year-old man with simultaneous bilateral rupture of the patellar tendon caused by minor trauma. The patient is a retired basketball player with no past complaints of chronic knee pain and a history of steroid use. Surgical management consisted in primary end-to-end tendon repair protected temporarily with cerclage wiring, followed by a short immobilization period and intensive rehabilitation program. Five months after surgery, the patient was able to fully participate in sport activities.

  6. Rectus Femoris Tendon Calcification

    PubMed Central

    Zini, Raul; Panascì, Manlio; Papalia, Rocco; Franceschi, Francesco; Vasta, Sebastiano; Denaro, Vincenzo

    2014-01-01

    Background: Since it was developed, hip arthroscopy has become the favored treatment for femoroacetabular impingement. Due to recent considerable improvements, the indications for this technique have been widely extended. Injuries of the rectus femoris tendon origin, after an acute phase, could result in a chronic tendinopathy with calcium hydroxyapatite crystal deposition, leading to pain and loss of function. Traditionally, this condition is addressed by local injection of anesthetic and corticosteroids or, when conservative measures fail, by open excision of the calcific lesion by an anterior approach. Purpose: To assess whether arthroscopic excision of calcification of the proximal rectus is a safe and effective treatment. Study Design: Case series; Level of evidence, 4. Methods: Outcomes were studied from 6 top amateur athletes (age range, 30-43 years; mean, 32.6 years) affected by calcification of the proximal rectus who underwent arthroscopic excision of the calcification. Patients were preoperatively assessed radiographically, and diagnosis was confirmed by a 3-dimensional computed tomography scan. To evaluate the outcome, standardized hip rating scores were used pre- and postoperatively (at 6 and 12 months): the Hip disability and Osteoarthritis Outcome Score, Oxford Hip Score, and Modified Harris Hip Score. Moreover, visual analog scales (VAS) for pain, sport activity level (SAL), and activities of daily living (ADL) were also used. Results: One year after surgery, all patients reported satisfactory outcomes, with 3 of 6 rating their return-to-sport level as high as preinjury level, and the remaining 3 with a percentage higher than 80%. Five patients ranked their ability to carry on daily activities at 100%. Statistical analysis showed significant improvement of the Oxford Hip Score, the Modified Harris Hip Score, and all 3 VAS subscales (pain, SAL, and ADL) from pre- to latest postoperative assessment (P < .05). Conclusion: Arthroscopic excision of

  7. Congenital Aberrant Tearing: A Re-Look

    PubMed Central

    Miller, Marilyn T.; Strömland, Kerstin; Ventura, Liana

    2008-01-01

    Purpose Congenital aberrant tearing is characterized by tearing when eating (“crocodile tears”), lack of emotional tearing, or both. Most reported cases are associated with Duane syndrome. In our previous studies we observed aberrant tearing in individuals with thalidomide embryopathy and Möbius sequence. This report summarizes the literature on the subject and adds 3 new studies that give information on this unusual condition. Methods Twenty-eight individuals with Möbius sequence were interviewed about tearing symptoms at a support group meeting in Italy. In Sweden 30 adults primarily from the original thalidomide series were reexamined. In this latter study, a Schirmer test was done at baseline and repeated 5 minutes after eating. Twenty families in Brazil who have children with Möbius sequence were questioned about tearing symptoms and exposure to misoprostol during pregnancy. Results In the 28 Italian individuals, either “crocodile tears” or lack of emotional tearing was noted in 7 cases. In the thalidomide study, 10 of 30 patients had tearing when eating and 7 had no emotional tearing. Low Schirmer scores or increased tearing after eating was noted in a few asymptomatic individuals. Among the 20 Brazilian children with Möbius sequence, 10 had some tearing abnormality. Conclusion Congenital anomalous lacrimation is rare but usually associated with Duane syndrome or abduction deficits, as in Möbius sequence and, less frequently, facial nerve palsy. Studies implicate an early insult in development at 4 to 6 weeks. At that time the facial nerve, sixth nerve, and lacrimal nucleus are in close proximity in the embryo. PMID:19277226

  8. Arthroscopic transtendinous repair of articular-sided pasta (partial articular supraspinatus tendon avulsion) injury

    PubMed Central

    Wang, Yi; Lu, Liangyu; Lu, Zhe; Xiao, Lei; Kang, Yifan; Wang, Zimin

    2015-01-01

    Objective: To evaluate clinical efficacy of arthroscopic transtendinous repair of partial articular-sided PASTA (partial articular supraspinatus tendon avulsion) injury. Methods: From February 2011 to July 2014, 12 cases of PASTA, aged 29 to 72 years with an average of 52.9 ± 13.3 years, were treated arthoscopically. To repair PASTA, articular-sided rotator cuff tear was explored, injury site was punctured and labeled with PDS absorbable monofilament suture (Ethicon, Somerville, NJ, USA) suture, subacromial bursa was cleaned up with acromioplasty, and integrity of bursa-side rotator cuff was assessed. Then with arthroscope in glenohumeral joint, footprint of the bursa-side supraspinatus tendon was preserved, rivets were introduced into the joint through supraspinatus tendon, joint-side partial tear was sutured, and anatomical reconstruction of the rotator cuff footprint was established. The patients were followed up post-operatively for 12-36 months, average 22 ± 7.3 months. The clinical outcomes were emulated with ASES (American Shoulder and Elbow Surgeons) Shoulder Score system and UCLA (University of California at Los Angeles) Shoulder rating scale. Results: The post-operative ASES score was 89.7 ± 5.6, higher than the pre-operative one 49.8 ± 9.8 (t = 12.25, P <0.0001). While UCLA scale increased from the pre-operative 17.3, ± 3.3 to the post-operative 30.4 ± 3.2 points (t = 9.87, P <0.0001), with a satisfaction rate of 11/12 (91.7%). Conclusion: Trans-tendon repair is ideal for PASTA with advantage of maximal preservation of the normal rotator cuff tissue, anatomical reconstruction of the rotator cuff footprint and stable fixation of tendon-bone interface. PMID:25784979

  9. Triceps Tendon Ruptures Requiring Surgical Repair in National Football League Players

    PubMed Central

    Finstein, Joseph L.; Cohen, Steven B.; Dodson, Christopher C.; Ciccotti, Michael G.; Marchetto, Paul; Pepe, Matthew D.; Deluca, Peter F.

    2015-01-01

    Background: Complete triceps tendon ruptures are relatively rare in the general population but slightly more prevalent in professional football. One prior study found 11 complete ruptures over a 6-season period. Hypothesis: Triceps ruptures occur more commonly in football linemen due to forced elbow flexion during an eccentric contraction and may occur more commonly with the increasing size and speed of professional players. Surgical repair allows full return to sports, but with a lengthy recovery time. Study Design: Case series; Level of evidence, 4. Methods: A search of the National Football League Injury Surveillance System (NFLISS) found a total of 37 triceps tendon ruptures requiring surgical repair from the years 2000 to 2009. Data were obtained for setting of injury, player position, activity causing injury, play type, time of game when injury occurred, height, weight, body mass index (BMI), and number of days lost from football. Results: There were 37 players requiring surgical repair for triceps tendon ruptures over the 10-season period. The average height, weight, and BMI of the players were 75 inches, 292 pounds, and 36.5 kg/m2, respectively. The majority of players were linemen (86%): 16 defensive, 15 offensive, and 1 tight end. The injury took place while blocking or being blocked in 29 players (78%) and while tackling or being tackled in 5 players (14%). Players missed an average of 165 days (range, 49-318 days) from football as a result of their injury and surgery. Conclusion: Triceps tendon tears requiring surgical repair are more common in professional football players than in the general population and are occurring more commonly than previously reported. Surgical repair allows return to play. Clinical Relevance: Our study identifies the rate of triceps tendon tears requiring repair in the NFL according to position, identifying which players may be most at risk for this injury. PMID:26535394

  10. Snapping knee caused by a popliteomeniscal fascicle tear of the lateral meniscus in a professional Taekwondo athlete.

    PubMed

    Park, Jong-Hoon; Ro, Kyung-Han; Lee, Dae-Hee

    2012-07-01

    A 19-year-old male professional Taekwondo athlete presented with a 2-year history of pain-free snapping of his right knee. He reported that his right knee joint gave way during games and training and that he could induce pain-free snapping between the proximal-to-fibular head and the lateral knee joint line. None of these physical findings suggested a meniscal pathology or ligamentous instability. Routine radiographs were normal. Magnetic resonance imaging of his right knee joint showed that the shape of the lateral meniscus was normal, and no lateral meniscus tears existed. On arthroscopic examination, popliteal hiatus view showed a posterosuperior popliteomeniscal fascicle tear between the posterior horn of the lateral meniscus and the posterior joint capsule just posteromedial to the popliteus tendon. With medial traction by probing, this popliteomeniscal tear made visible the significant subluxation of the posterior horn of the lateral meniscus to the center or anterior half of the tibial plateau. Based on the diagnosis of a posterosuperior popliteomeniscal tear of the right knee, Fast-Fix (Smith & Nephew, Andover, Massachusetts) was used for the direct repair of the peripheral portion of the lateral meniscus and joint capsule, targeting the popliteomeniscal junction. At 24 months postoperatively, the patient was performing athletic exercises relevant to his profession and was taking part in Taekwondo games, with no pain or recurrence of snapping. To the authors' knowledge, this is the first report of snapping of the lateral aspect of the knee due to a popliteomeniscal fascicle tear.

  11. 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

  12. Faster Movement Speed Results in Greater Tendon Strain during the Loaded Squat Exercise

    PubMed Central

    Earp, Jacob E.; Newton, Robert U.; Cormie, Prue; Blazevich, Anthony J.

    2016-01-01

    Introduction: Tendon dynamics influence movement performance and provide the stimulus for long-term tendon adaptation. As tendon strain increases with load magnitude and decreases with loading rate, changes in movement speed during exercise should influence tendon strain. Methods: Ten resistance-trained men [squat one repetition maximum (1RM) to body mass ratio: 1.65 ± 0.12] performed parallel-depth back squat lifts with 60% of 1RM load at three different speeds: slow fixed-tempo (TS: 2-s eccentric, 1-s pause, 2-s concentric), volitional-speed without a pause (VS) and maximum-speed jump (JS). In each condition joint kinetics, quadriceps tendon length (LT), patellar tendon force (FT), and rate of force development (RFDT) were estimated using integrated ultrasonography, motion-capture, and force platform recordings. Results: Peak LT, FT, and RFDT were greater in JS than TS (p < 0.05), however no differences were observed between VS and TS. Thus, moving at faster speeds resulted in both greater tendon stress and strain despite an increased RFDT, as would be predicted of an elastic, but not a viscous, structure. Temporal comparisons showed that LT was greater in TS than JS during the early eccentric phase (10–14% movement duration) where peak RFDT occurred, demonstrating that the tendon's viscous properties predominated during initial eccentric loading. However, during the concentric phase (61–70 and 76–83% movement duration) differing FT and similar RFDT between conditions allowed for the tendon's elastic properties to predominate such that peak tendon strain was greater in JS than TS. Conclusions: Based on our current understanding, there may be an additional mechanical stimulus for tendon adaptation when performing large range-of-motion isoinertial exercises at faster movement speeds. PMID:27630574

  13. Tear-Duct Obstruction and Surgery

    MedlinePlus

    ... Treating Blocked Tear Ducts Surgical Treatments en español Obstrucción y cirugía del conducto nasolagrimal Many babies are ... of the eyes (between the eyes and the nose). From the lacrimal sacs, tears move down through ...

  14. Interferometric characterization of tear film dynamics

    NASA Astrophysics Data System (ADS)

    Primeau, Brian Christopher

    The anterior refracting surface of the eye is the thin tear film that forms on the surface of the cornea. When a contact lens is on worn, the tear film covers the contact lens as it would a bare cornea, and is affected by the contact lens material properties. Tear film irregularity can cause both discomfort and vision quality degradation. Under normal conditions, the tear film is less than 10 microns thick and the thickness and topography change in the time between blinks. In order to both better understand the tear film, and to characterize how contact lenses affect tear film behavior, two interferometers were designed and built to separately measure tear film behavior in vitro and in vivo. An in vitro method of characterizing dynamic fluid layers applied to contact lenses mounted on mechanical substrates has been developed using a phase-shifting Twyman-Green interferometer. This interferometer continuously measures light reflected from the surface of the fluid layer, allowing precision analysis of the dynamic fluid layer. Movies showing this fluid layer behavior can be generated. The fluid behavior on the contact lens surface is measured, allowing quantitative analysis beyond what typical contact angle or visual inspection methods provide. The in vivo interferometer is a similar system, with additional modules included to provide capability for human testing. This tear film measurement allows analysis beyond capabilities of typical fluorescein visual inspection or videokeratometry and provides better sensitivity and resolution than shearing interferometry methods.

  15. Tear gas: an epidemiological and mechanistic reassessment

    PubMed Central

    Rothenberg, Craig; Achanta, Satyanarayana; Svendsen, Erik R.

    2016-01-01

    Deployments of tear gas and pepper spray have rapidly increased worldwide. Large amounts of tear gas have been used in densely populated cities, including Cairo, Istanbul, Rio de Janeiro, Manama (Bahrain), and Hong Kong. In the United States, tear gas was used extensively during recent riots in Ferguson, Missouri. Whereas tear gas deployment systems have rapidly improved—with aerial drone systems tested and requested by law enforcement—epidemiological and mechanistic research have lagged behind and have received little attention. Case studies and recent epidemiological studies revealed that tear gas agents can cause lung, cutaneous, and ocular injuries, with individuals affected by chronic morbidities at high risk for complications. Mechanistic studies identified the ion channels TRPV1 and TRPA1 as targets of capsaicin in pepper spray, and of the tear gas agents chloroacetophenone, CS, and CR. TRPV1 and TRPA1 localize to pain‐sensing peripheral sensory neurons and have been linked to acute and chronic pain, cough, asthma, lung injury, dermatitis, itch, and neurodegeneration. In animal models, transient receptor potential inhibitors show promising effects as potential countermeasures against tear gas injuries. On the basis of the available data, a reassessment of the health risks of tear gas exposures in the civilian population is advised, and development of new countermeasures is proposed. PMID:27391380

  16. Tear gas: an epidemiological and mechanistic reassessment.

    PubMed

    Rothenberg, Craig; Achanta, Satyanarayana; Svendsen, Erik R; Jordt, Sven-Eric

    2016-08-01

    Deployments of tear gas and pepper spray have rapidly increased worldwide. Large amounts of tear gas have been used in densely populated cities, including Cairo, Istanbul, Rio de Janeiro, Manama (Bahrain), and Hong Kong. In the United States, tear gas was used extensively during recent riots in Ferguson, Missouri. Whereas tear gas deployment systems have rapidly improved-with aerial drone systems tested and requested by law enforcement-epidemiological and mechanistic research have lagged behind and have received little attention. Case studies and recent epidemiological studies revealed that tear gas agents can cause lung, cutaneous, and ocular injuries, with individuals affected by chronic morbidities at high risk for complications. Mechanistic studies identified the ion channels TRPV1 and TRPA1 as targets of capsaicin in pepper spray, and of the tear gas agents chloroacetophenone, CS, and CR. TRPV1 and TRPA1 localize to pain-sensing peripheral sensory neurons and have been linked to acute and chronic pain, cough, asthma, lung injury, dermatitis, itch, and neurodegeneration. In animal models, transient receptor potential inhibitors show promising effects as potential countermeasures against tear gas injuries. On the basis of the available data, a reassessment of the health risks of tear gas exposures in the civilian population is advised, and development of new countermeasures is proposed.

  17. 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

  18. Automatic CAD of meniscal tears on MR imaging: a morphology-based approach

    NASA Astrophysics Data System (ADS)

    Ramakrishna, Bharath; Liu, Weimin; Safdar, Nabile; Siddiqui, Khan; Kim, Woojin; Juluru, Krishna; Chang, Chein-I.; Siegel, Eliot

    2007-03-01

    Knee-related injuries, including meniscal tears, are common in young athletes and require accurate diagnosis and appropriate surgical intervention. Although with proper technique and skill, confidence in the detection of meniscal tears should be high, this task continues to be a challenge for many inexperienced radiologists. The purpose of our study was to automate detection of meniscal tears of the knee using a computer-aided detection (CAD) algorithm. Automated segmentation of the sagittal T1-weighted MR imaging sequences of the knee in 28 patients with diagnoses of meniscal tears was performed using morphologic image processing in a 3-step process including cropping, thresholding, and application of morphological constraints. After meniscal segmentation, abnormal linear meniscal signal was extracted through a second thresholding process. The results of this process were validated by comparison with the interpretations of 2 board-certified musculoskeletal radiologists. The automated meniscal extraction algorithm process was able to successfully perform region of interest selection, thresholding, and object shape constraint tasks to produce a convex image isolating the menisci in more than 69% of the 28 cases. A high correlation was also noted between the CAD algorithm and human observer results in identification of complex meniscal tears. Our initial investigation indicates considerable promise for automatic detection of simple and complex meniscal tears of the knee using the CAD algorithm. This observation poses interesting possibilities for increasing radiologist productivity and confidence, improving patient outcomes, and applying more sophisticated CAD algorithms to orthopedic imaging tasks.

  19. Tear Osmolarity in Sjogren’s Syndrome

    PubMed Central

    Bunya, Vatinee Y.; Langelier, Nicole; Chen, Sarah; Pistilli, Maxwell; Vivino, Frederick B.; Massaro-Giordano, Giacomina

    2013-01-01

    Purpose The Schirmer test is one of two ocular surface tests included in the current classification criteria for Sjögren’s Syndrome (SS). Tear osmolarity may also be a useful test for the diagnosis of dry eye disease. The purpose of this study was to examine the relationship between tear osmolarity, the Schirmer test I, and dry eye symptoms in SS. Methods Patients with a diagnosis of SS were assessed for tear osmolarity with the TearLab™ Osmolarity System, tear production with Schirmer testing, symptoms with the Ocular Surface Disease Index (OSDI), and discomfort associated with each test. Results Forty-nine patients with a mean age of 53.7 years and a female (92%) predominance were enrolled. The majority of patients (86%) were receiving systemic therapy for severe SS. Higher tear osmolarity was moderately associated with lower scores on the Schirmer test I (ρ = −0.39, P < 0.01) and with lower scores on the OSDI (ρ = −0.45, P < 0.01). Schirmer test I results and lower OSDI scores were not correlated significantly (ρ = 0.20, P = 0.17). Tear osmolarity testing was significantly less painful than Schirmer testing (P < 0.01). Conclusions Signs and symptoms of dry eye in SS patients were not strongly correlated. An unexpected finding was that higher tear osmolarity was associated with lower symptom severity. Tear osmolarity testing in the clinical setting was feasible and was associated with significantly less discomfort than Schirmer testing in patients with severe SS. PMID:23407318

  20. Structural and mechanical integrity of tendon-to-tendon attachments used in upper limb tendon transfer surgery.

    PubMed

    Tsiampa, Vassiliki A; Ignatiadis, Ioannis; Papalois, Apostolos; Givissis, Panayiotis; Christodoulou, Anastasios; Fridén, Jan

    2012-09-01

    Improved tendon-to-tendon suturing techniques allow for consistent and immediate activation of transferred muscle after surgery. A pre-requisite for early training after tendon transfer surgery is sufficient mechanical integrity of the tendon-to-tendon attachment. This in vitro study compared the mechanisms and magnitudes of load-to-failure response of two different repair techniques (side-to-side running, n = 7) and weave sutures (n = 8) in sheep front foot tendons. Tensile tests were performed by placing pre-conditioned tendons in a testing machine and stretching at a constant speed to failure. The length of the tendons overlap was the same (50 mm) for both repair techniques. The results of the load to failure tests showed that the side-to-side repairs were significantly stronger than the weave repairs. The failure mechanisms were also different. While the side-to-side attachment failed by longitudinal separation of tendon material of the donor tendon but with the fibres locked to the running sutures attached to the recipient tendon, the weave repairs failed by knot slipping or by suture pullout from the tendon substance. It is concluded that use of the side-to-side repair technique can provide early active training of new motors that not only prevent the formation of adhesions but also facilitate the voluntary recruitment of motors powering new functions before immobilisation-related swelling and stiffness restrain muscle contractions.

  1. Prediction of the elastic strain limit of tendons.

    PubMed

    Reyes, A M; Jahr, H; van Schie, H T M; Weinans, H; Zadpoor, A A

    2014-02-01

    The elastic strain limit (ESL) of tendons is the point where maximum elastic modulus is reached, after which micro-damage starts. Study of damage progression in tendons under repetitive (fatigue) loading requires a priori knowledge about ESL. In this study, we propose three different approaches for predicting ESL. First, one single value is assumed to represent the ESL of all tendon specimens. Second, different extrapolation curves are used for extrapolating the initial part of the stress-strain curve. Third, a method based on comparing the shape of the initial part of the stress-strain curve of specimens with a database of stress-strain curves is used. A large number of porcine tendon explants (97) were tested to examine the above-mentioned approaches. The variants of the third approach yielded significantly (p<0.05) smaller error values as compared to the other approaches. The mean absolute percentage error of the best-performing variant of the shape-based comparison was between 8.14±6.44% and 9.96±9.99% depending on the size of the initial part of the stress-strain curves. Interspecies generalizability of the best performing method was also studied by applying it for prediction of the ESL of horse tendons. The ESL of horse tendons was predicted with mean absolute percentage errors ranging between 10.53±7.6% and 19.16±14.31% depending on the size of the initial part of the stress-strain curves and the type of normalization. The results of this study suggest that both ESL and the shape of stress-strain curves may be highly different between different individuals and different anatomical locations.

  2. Proprioceptive deficit in individuals with unilateral tearing of the anterior cruciate ligament after active evaluation of the sense of joint position☆☆☆

    PubMed Central

    Cossich, Victor; Mallrich, Frédéric; Titonelli, Victor; de Sousa, Eduardo Branco; Velasques, Bruna; Salles, José Inácio

    2014-01-01

    Objective To ascertain whether the proprioceptive deficit in the sense of joint position continues to be present when patients with a limb presenting a deficient anterior cruciate ligament (ACL) are assessed by testing their active reproduction of joint position, in comparison with the contralateral limb. Methods Twenty patients with unilateral ACL tearing participated in the study. Their active reproduction of joint position in the limb with the deficient ACL and in the healthy contralateral limb was tested. Meta-positions of 20% and 50% of the maximum joint range of motion were used. Proprioceptive performance was determined through the values of the absolute error, variable error and constant error. Results Significant differences in absolute error were found at both of the positions evaluated, and in constant error at 50% of the maximum joint range of motion. Conclusion When evaluated in terms of absolute error, the proprioceptive deficit continues to be present even when an active evaluation of the sense of joint position is made. Consequently, this sense involves activity of both intramuscular and tendon receptors. PMID:26229869

  3. Inhibition of prolyl 4-hydroxylase decreases muscle fibrosis following chronic rotator cuff tear

    PubMed Central

    Gumucio, J. P.; Flood, M. D.; Bedi, A.; Kramer, H. F.; Russell, A. J.

    2017-01-01

    Objectives Rotator cuff tears are among the most frequent upper extremity injuries. Current treatment strategies do not address the poor quality of the muscle and tendon following chronic rotator cuff tears. Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor that activates many genes that are important in skeletal muscle regeneration. HIF-1α is inhibited under normal physiological conditions by the HIF prolyl 4-hydroxylases (PHDs). In this study, we used a pharmacological PHD inhibitor, GSK1120360A, to enhance the activity of HIF-1α following the repair of a chronic cuff tear, and measured muscle fibre contractility, fibrosis, gene expression, and enthesis mechanics. Methods Chronic supraspinatus tears were induced in adult rats, and repaired 28 days later. Rats received 0 mg/kg, 3 mg/kg, or 10 mg/kg GSK1120360A daily. Collagen content, contractility, fibre type distribution and size, the expression of genes involved in fibrosis, lipid accumulation, atrophy and inflammation, and the mechanical properties of the enthesis were then assessed two weeks following surgical repair. Results At two weeks following repair, treatment groups showed increased muscle mass but there was a 15% decrease in force production in the 10 mg/kg group from controls, and no difference between the 0 mg/kg and the 3 mg/kg groups. There was a decrease in the expression of several gene transcripts related to matrix accumulation and fibrosis, and a 50% decrease in collagen content in both treated groups compared with controls. Additionally, the expression of inflammatory genes was reduced in the treated groups compared with controls. Finally, PHD inhibition improved the maximum stress and displacement to failure in repaired tendons. Conclusions GSK1120360A resulted in improved enthesis mechanics with variable effects on muscle function. PHD inhibition may be beneficial for connective tissue injuries in which muscle atrophy has not occurred. Cite this article: J. P. Gumucio

  4. Triceps tendon rupture in weight lifters.

    PubMed

    Sollender, J L; Rayan, G M; Barden, G A

    1998-01-01

    Triceps tendon avulsion injuries are rare. We report four weight lifters with triceps tendon raptures, two of whom had received local steroid injections for pain in the triceps. All four patients had taken oral anabolic steroids before injury. All patients had closed avulsion of the triceps tendon from its insertion into the olecranon. Three patients were injured while bench pressing heavy weights, and one patient was injured while swinging a baseball bat. Satisfactory results were achieved after surgical reinsertion of the tendon.

  5. Ultrasound of tibialis anterior muscle and tendon: anatomy, technique of examination, normal and pathologic appearance.

    PubMed

    Varghese, Ajay; Bianchi, Stefano

    2014-06-01

    Lesions of the tibialis anterior muscle and tendon are not frequently reported in international literature although pathology is not rare. Pathology can be spontaneous, associated with arthropathy or more generalized conditions. Clinical assessment may not be sufficient for distinguishing conditions like tendinopathy, tears, bursitis, etc. Therefore, imaging studies are necessary to plan appropriate therapy. US has a number of advantages, including widespread availability, absence of contraindications and low cost. It can also be used for dynamic studies of the muscle during contraction and relaxation. This article reviews the anatomy of the tibialis anterior, normal variants, the technique used for standard US examination of this muscle and tendon, its normal appearance on US and the sonographic characteristics of the most common lesions that affect it including tips on US-guided injections used for treatment.

  6. The influence of testing angle on the biomechanical properties of the rat supraspinatus tendon.

    PubMed

    Newton, Michael D; Davidson, Abigail A; Pomajzl, Ryan; Seta, Joseph; Kurdziel, Michael D; Maerz, Tristan

    2016-12-08

    Rotator cuff tears are a common shoulder pathology. The rat supraspinatus tendon model is commonly employed for preclinical assessment of rotator cuff pathology or regeneration. However, there is a lack of a standardized biomechanical testing protocol; previous studies have tested the tendon at abduction angles ranging from -15° to 90°. This study aimed to assess the effect of abduction/testing angle on the biomechanical properties of the rat supraspinatus tendon. Fourty-eight shoulders (n=12/group) from healthy Sprague-Dawley rats were randomized to 4 testing angle groups: 0° (corresponding to 90° abduction), 30°, 60°, and 90° (0° abduction). Biomechanical testing of the supraspinatus was performed, consisting of stress-relaxation and load-to-failure. Mechanical properties were calculated, and nonlinear tensile modeling was performed via the Quasilinear Viscoelastic (QLV) and Structurally Based Elastic (SBE) models. Results indicate that testing angle significantly affects supraspinatus tendon biomechanics. Stiffness and modulus significantly decreased with increasing testing angle (stiffness: 20.93±5.8N/mm at 0° vs. 6.12±1.0N/mm at 90°, P<.001; modulus: 59.51±34.0MPa at 0° vs. 22.37±7.4MPa at 90°, P=.002). Testing angle correlated significantly to ultimate strain, yield strain, and all coefficients of the SBE and QLV models, implying differences in collagen fiber crimp patterns and viscoelastic behavior as a function of testing angle. These results suggest that differences in testing methodology, in particular testing angle, significantly affect the measured mechanical properties of the supraspinatus tendon. Future studies may consider utilizing testing angles of 0°-30°, at which tendon stiffness is maximized, and full standardization of rat rotator cuff testing protocols is necessary.

  7. 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.

  8. 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.

  9. Use of the Taguchi method for biomechanical comparison of flexor-tendon-repair techniques to allow immediate active flexion. A new method of analysis and optimization of technique to improve the quality of the repair.

    PubMed

    Singer, G; Ebramzadeh, E; Jones, N F; Meals, R

    1998-10-01

    The current trend toward early active flexion after repair of the flexor tendons necessitates a stronger repair than that provided by a modified Kessler technique with use of 4-0 nylon suture. The purpose of the current study was to determine, with use of the Taguchi method of analysis, the strongest and most consistent repair of the flexor tendons. Flexor tendons were obtained from fresh-frozen hands of human cadavera. Eight flexor tendons initially were repaired with the modified Kessler technique with use of 4-0 nylon core suture and 6-0 nylon epitenon suture. A test matrix was used to analyze a total of twenty variables in sixty-four tests. These variables included eight techniques for core-suture repair, four types of core suture, two sizes of core suture, four techniques for suture of the epitenon, and two distances from the repair site for placement of the core suture. After each repair, the specimens were mounted in a servohydraulic mechanical testing machine for tension-testing to failure. The optimum combination of variables was determined, with the Taguchi method, to be an augmented Becker technique with use of 3-0 Mersilene core suture, placed 0.75 centimeter from the cut edge with volar epitenon suture. The four-strand, double modified Kessler technique provided the second strongest repair. Five tendons that had been repaired with use of the optimum combination then were tested and compared with tendons that had been repaired with the standard modified Kessler technique. With the optimum combination of variables, the strength of the repair improved from a mean (and standard deviation) of 17.2 +/- 2.9 to 128 +/- 5.6 newtons, and the stiffness improved from a mean of 4.6 to 16.2 newtons per millimeter.

  10. REHABILITATION OF A PARTIALLY TORN DISTAL TRICEPS TENDON AFTER PLATELET RICH PLASMA INJECTION: A CASE REPORT

    PubMed Central

    Kolber, Morey J.; Salamh, Paul A.; Hanney, William J.

    2013-01-01

    Background: Platelet Rich Plasma (PRP) is an emerging non‐surgical intervention used for the treatment of tendon and ligament pathology. Despite the growing popularity of PRP in musculoskeletal medicine, there is a paucity of research that describes appropriate rehabilitation procedures following this intervention. Case Description: This case report presents the rehabilitation strategy used following a PRP injection for a patient with a partially torn distal triceps tendon who previously failed physical therapy interventions. Outcome: The patient returned to light weight training and coaching activity after completing 15 visits over a 3 month period. One month after discharge, the patient reported pain‐free activities of daily living and a return to previously performed gym activities. Discussion: PRP presents a viable treatment option for individuals who are recalcitrant to conservative interventions yet elect to avoid more invasive surgical measures. Despite the growing popularity of PRP, a paucity of evidence exists to guide physical therapists in the rehabilitation process of these patients. The rehabilitation strategies used in a patient who had a PRP injection for a partial triceps tendon tear are outlined. Although this case report highlights a successful rehabilitation outcome, future research regarding the concomitant effects of PRP injection and rehabilitation for tendon pathology are needed. Level of Evidence: 4‐Case Report PMID:23772345

  11. A novel way to treat skin tears.

    PubMed

    Moradian, Scott; Klapper, Andrew M

    2016-04-01

    Skin tears are one of the most commonly treated wounds in the elderly population. In their most basic form, they are essentially traumatic random pattern flaps. We postulate that the injured blood flow to these skin flaps should be ignored and the tissue should be treated as a skin graft. A case report is presented of an 86-year-old female with an 8 × 3·5 cm skin tear to her right upper extremity after a hip fracture. In addition to conventional wound closure strips re-approximating the tissues, a disposable negative pressure wound therapy device was placed to act as bolster. Upon its removal on day 5, the opposed skin tear tissue was found to be 100% viable. We therefore propose that this update may be an improvement over classical skin tear treatments and should be followed up with a case series.

  12. On the tear resistance of skin

    PubMed Central

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O.; Meyers, Marc A.

    2015-01-01

    Tear resistance is of vital importance in the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. We explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. We express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensile direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip. PMID:25812485

  13. On the tear resistance of skin

    NASA Astrophysics Data System (ADS)

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O.; Meyers, Marc A.

    2015-03-01

    Tear resistance is of vital importance in the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. We explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. We express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensile direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip.

  14. On the tear resistance of skin

    DOE PAGES

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; ...

    2015-03-27

    Tear resistance is vitally important for the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. Here we explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. Finally, we express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensilemore » direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip.« less

  15. On the tear resistance of skin

    SciTech Connect

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O.; Meyers, Marc A.

    2015-03-27

    Tear resistance is vitally important for the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. Here we explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. Finally, we express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensile direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip.

  16. Partial Thickness Rotator Cuff Tears: Current Concepts

    PubMed Central

    Matthewson, Graeme; Beach, Cara J.; Nelson, Atiba A.; Woodmass, Jarret M.; Ono, Yohei; Boorman, Richard S.; Lo, Ian K. Y.; Thornton, Gail M.

    2015-01-01

    Partial thickness rotator cuff tears are a common cause of pain in the adult shoulder. Despite their high prevalence, the diagnosis and treatment of partial thickness rotator cuff tears remains controversial. While recent studies have helped to elucidate the anatomy and natural history of disease progression, the optimal treatment, both nonoperative and operative, is unclear. Although the advent of arthroscopy has improved the accuracy of the diagnosis of partial thickness rotator cuff tears, the number of surgical techniques used to repair these tears has also increased. While multiple repair techniques have been described, there is currently no significant clinical evidence supporting more complex surgical techniques over standard rotator cuff repair. Further research is required to determine the clinical indications for surgical and nonsurgical management, when formal rotator cuff repair is specifically indicated and when biologic adjunctive therapy may be utilized. PMID:26171251

  17. Tear film MMP accumulation and corneal disease

    PubMed Central

    Smith, V; Rishmawi, H; Hussein, H; Easty, D

    2001-01-01

    BACKGROUND/AIMS—Matrix metalloproteinases (MMPs) accumulate in the tears of patients with active peripheral ulcerative keratitis (PUK) but it is unknown whether these enzymes have a central role in disease progression. The aims of the present investigation were to determine the source of these enzymes and to ascertain whether their accumulation in tears is a phenomenon specific to PUK or a general feature of other anterior segment diseases.
METHODS—The experimental samples were obtained from the culture media of conjunctival and corneal epithelial cells, from fractionated blood plasma and leucocytes of healthy subjects and patients with rheumatoid arthritis, and from the tears of healthy subjects and patients with a variety of anterior segment diseases. The MMPs of all samples were visualised by zymography and tear samples were assayed using nitrophenol acetate and an MMP-9 susceptible quenched fluorescent peptide as substrate.
RESULTS—The major MMPs that accumulate in the tears of patients with rheumatoid arthritis with active ocular disease are MMP-9 and a species of Mr 116 000. By comparing the zymographic activity profiles of the gelatinases present in the samples obtained, it was deduced that the main source of these MMPs was granulocytes. Their accumulation in tears was not unique to patients with PUK; detectable amounts of the enzymes also occurred in the tears of patients with keratoconus with associated atopic disease, patients undergoing treatment for herpetic eye disease, and patients with systemic and non-systemic dry eye disease.
CONCLUSION—The MMPs that accumulate in tears are mainly derived from granulocytes. This may be effected by autoimmune diseases that involve ocular tissue or by ocular diseases that induce an inflammatory response.

 PMID:11159476

  18. Tear film measurement by optical reflectometry technique.

    PubMed

    Lu, Hui; Wang, Michael R; Wang, Jianhua; Shen, Meixiao

    2014-02-01

    Evaluation of tear film is performed by an optical reflectometer system with alignment guided by a galvanometer scanner. The reflectometer system utilizes optical fibers to deliver illumination light to the tear film and collect the film reflectance as a function of wavelength. Film thickness is determined by best fitting the reflectance-wavelength curve. The spectral reflectance acquisition time is 15 ms, fast enough for detecting film thickness changes. Fast beam alignment of 1 s is achieved by the galvanometer scanner. The reflectometer was first used to evaluate artificial tear film on a model eye with and without a contact lens. The film thickness and thinning rate have been successfully quantified with the minimum measured thickness of about 0.3 μm. Tear films in human eyes, with and without a contact lens, have also been evaluated. A high-contrast spectral reflectance signal from the precontact lens tear film is clearly observed, and the thinning dynamics have been easily recorded from 3.69 to 1.31 μm with lipid layer thickness variation in the range of 41 to 67 nm. The accuracy of the measurement is better than ±0.58% of the film thickness at an estimated tear film refractive index error of ±0.001. The fiber-based reflectometer system is compact and easy to handle.

  19. Tear film measurement by optical reflectometry technique

    PubMed Central

    Lu, Hui; Wang, Michael R.; Wang, Jianhua; Shen, Meixiao

    2014-01-01

    Abstract. Evaluation of tear film is performed by an optical reflectometer system with alignment guided by a galvanometer scanner. The reflectometer system utilizes optical fibers to deliver illumination light to the tear film and collect the film reflectance as a function of wavelength. Film thickness is determined by best fitting the reflectance-wavelength curve. The spectral reflectance acquisition time is 15 ms, fast enough for detecting film thickness changes. Fast beam alignment of 1 s is achieved by the galvanometer scanner. The reflectometer was first used to evaluate artificial tear film on a model eye with and without a contact lens. The film thickness and thinning rate have been successfully quantified with the minimum measured thickness of about 0.3 μm. Tear films in human eyes, with and without a contact lens, have also been evaluated. A high-contrast spectral reflectance signal from the precontact lens tear film is clearly observed, and the thinning dynamics have been easily recorded from 3.69 to 1.31 μm with lipid layer thickness variation in the range of 41 to 67 nm. The accuracy of the measurement is better than ±0.58% of the film thickness at an estimated tear film refractive index error of ±0.001. The fiber-based reflectometer system is compact and easy to handle. PMID:24500519

  20. The clinical effect of tendon repair for tendon spontaneous rupture after corticosteroid injection in hands

    PubMed Central

    Lu, Hui; Yang, Hu; Shen, Hui; Ye, Ganmin; Lin, Xiang-Jin

    2016-01-01

    Abstract Corticosteroid injections for hand tendinitis can lead to a rare significant complication of tendon spontaneous rupture. However, only sporadic cases were reported in the literature before. This study was designed to gauge the clinical effect of tendon repair in patients of tendon spontaneous rupture after corticosteroid injection and analyze our experience. This was a retrospective observational study of 13 patients (8 women and 5 men) operated between July 2011 and December 2015 for tendon spontaneous rupture after corticosteroid injection. Demographic data, clinical features, imaging data, and surgical treatments were carefully reviewed. The average age was 52.308 ± 15.381 years (range 29–71). The average injection times were 2.538 ± 1.664 times (range 1–6). The average rupture time (after last injection) was 10.923 ± 9.500 weeks (range 3–32). Nine patients were treated by tendon suture (69% of cases), and 4 patients were treated by tendon grafting (31% of cases). All patients received follow-up in our outpatient clinic. The sites of the tendon rupture (15 tendons of 13 patients had involved) include extensor pollicis longus (6 tendons, 40% of cases), extensor digiti quinti and extensor digiti minimi (4 tendons, 27% of cases), ring finger of extensor digitorum communis (3 tendons, 20% of cases), and middle finger of extensor digitorum communis (2 tendons, 13% of cases). Two patients who had tendon adhesion (15% of cases) were treated by tendon release. One patient who had tendon rerupture (8% of cases) was treated by tendon grafting. No patient had complications of infections, vascular, or nerve injury. Tendon spontaneous rupture is a serious complication after corticosteroid injection for tendinitis. Rigid standard of corticosteroid injection is very important. Magnetic resonance imaging was contributory to preoperative assess tendon defect and can be used to monitor healing quality of tendons during the follow-up. PMID:27741145

  1. [The rupture of the tibial anterior tendon in a world class veteran fencer].

    PubMed

    Kelm, J; Anagnostakos, K; Deubel, G; Schliessing, P; Schmitt, E

    2004-09-01

    The rupture of the tendon of the M. tibialis ant. is a rare sport injury and has not been yet described in fencing. The lunge, the most common offensive movement in fencing, displays a high stress on the spanned tendons and ligaments over the ankle joint and led to the rupture of the pre-damaged tendon of our patient. Pain over the inner side of the foot should be assessed as knells of this tendon injury. The exact patient's history and the precise clinical investigation are adequate for diagnosing the rupture. Hereby, an absence of the tendon shape over the ankle joint and a distinct active deficit of the extension are presented in comparison to the other side where a gap in the tendon course is palpable. An x-ray is obligate, a sonography and a MRI are helpful for the operative planning. The surgical treatment is necessary for athletes. If possible, a primary tendon suture should be aimed, in case of a distal torn an osseous reinsertion should occur. An early functional, postoperative treatment with an orthesis should be rather preferred for athletes than an immobilization.

  2. 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

  3. Alteration of Galectin-3 in Tears of Patients with Dry Eye Disease

    PubMed Central

    Uchino, Yuichi; Mauris, Jerome; Woodward, Ashley M.; Dieckow, Julia; Amparo, Francisco; Dana, Reza; Mantelli, Flavio; Argüeso, Pablo

    2015-01-01

    Purpose To investigate the expression, release, and proteolytic degradation of galectin-3 in patients with dry eye disease. Design Observational case series with a comparison group. Methods Tear washes and conjunctival impression cytology specimens were collected through standard procedures from 16 patients with dry eye and 11 age-matched healthy subjects. Galectin-3 content in tears was analyzed by quantitative Western blot, using recombinant galectin-3 protein to generate a calibration curve. The relative expression of galectin-3 and matrix metalloproteinase 9 (MMP9) was evaluated by quantitative polymerase chain reaction. The cleavage of galectin-3 was studied in vitro using activated recombinant MMP9 and protease inhibitors. Results The concentration of galectin-3 protein in tears, but not galectin-3 expression in conjunctival epithelium, was significantly higher in tears of patients with dry eye (0.38 ng/μg total protein, range 0.04-1.36) compared to healthy subjects (0.12 ng/μg total protein, range 0.00-0.41) (P < .01). By Western blot, an intact (∼28.0 kDa) galectin-3 band was identified in tear samples from healthy subjects, whereas 50% of the dry eye samples were characterized by the additional presence of a partially degraded form (∼25.4 kDa). In our experiments, elevated expression of MMP9 in dry eye subjects correlated with the ability of active MMP9 to cleave galectin-3 from recombinant origin. Interestingly, cleavage of endogenous galectin-3 in tear samples was impaired using a broad-spectrum proteinase inhibitor cocktail, but not the pan-specific MMP inhibitor GM6001, suggesting the presence of proteases other than MMPs in promoting galectin-3 degradation in dry eye. Conclusions Our results indicate that release of cellular galectin-3 into tears is associated with epithelial dysfunction in dry eye, and that galectin-3 proteolytic cleavage may contribute to impaired ocular surface barrier function. PMID:25703476

  4. Tear metabolite changes in keratoconus

    PubMed Central

    Karamichos, D; Zieske, JD; Sejersen, H; Sarker-Nag, A; Asara, John M; Hjortdal, J

    2015-01-01

    While efforts have been made over the years, the exact cause of keratoconus (KC) remains unknown. The aim of this study was to identify alterations in endogenous metabolites in the tears of KC patients compared with age-matched healthy subjects. Three groups were tested: 1) Age-matched controls with no eye disease (N=15), 2) KC – patients wearing Rigid Gas permeable lenses (N=16), and 3) KC – No Correction (N=14). All samples were processed for metabolomics analysis using LC-MS/MS. We identified a total of 296 different metabolites of which >40 were significantly regulated between groups. Glycolysis and gluconeogenesis had significant changes, such as 3-phosphoglycerate and 1,3 diphopshateglycerate. As a result the citric acid cycle (TCA) was also affected with notable changes in Isocitrate, aconitate, malate, and acetylphosphate, up regulated in Group 2 and/or 3. Urea cycle was also affected, especially in Group 3 where ornithine and aspartate were up-regulated by at least 3 fold. The oxidation state was also severely affected. Groups 2 and 3 were under severe oxidative stress causing multiple metabolites to be regulated when compared to Group 1. Group 2 and 3, both showed significant down regulation in GSH-to-GSSG ratio when compared to Group 1. Another indicator of oxidative stress, the ratio of lactate – pyruvate was also affected with Groups 2 and 3 showing at least a 2-fold up regulation. Overall, our data indicate that levels of metabolites related to urea cycle, TCA cycle and oxidative stress are highly altered in KC patients. PMID:25579606

  5. 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.

  6. 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

  7. 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

  8. Molecular mechanism of fatty degeneration in rotator cuff muscle with tendon rupture.

    PubMed

    Itoigawa, Yoshiaki; Kishimoto, Koshi N; Sano, Hirotaka; Kaneko, Kazuo; Itoi, Eiji

    2011-06-01

    Fatty degeneration often occurs in rotator cuff muscle with tendon rupture. However, the molecular mechanism underlying this change has not been fully clarified yet. We investigated the gene expression of Wnt10b and adipogenic marker gene, PPARγ and C/EBPα in C2C12 myogenic cell line under inhibition of Wnt10b by adipogenic induction medium, isobutylmethylxanthine, dexamethasone, and insulin (MDI). The role of Wnt-signal was confirmed by adding Lithium chloride (LiCl), which mimics Wnt signaling to the cultured cell with MDI. We also assessed the expression profiles of same genes in the rat rotator cuff tear model in vivo. MDI induced Oil red-O staining positive adipocytes and upregulated PPARγ and C/EBPα expression. LiCl inhibited adipogenic induction of MDI. Rotator cuff muscle with tendon rupture showed positive staining for Oil red-O. Real-time polymerase chain reaction analyses revealed decreased expression of Wnt10b followed by increased PPARγ and C/EBPα gene expression in the supraspinatus muscle. Fatty degeneration and its molecular events were remarkably seen in the distal one-third of the detached supraspinatus muscle versus control. Wnt signaling may regulate adipogenic differentiation both in the myoblasts in vitro and the muscle in vivo. Our results indicate that the reduction of Wnt10b in muscle with a rotator cuff tear is a key signal in fatty degeneration of the muscle.

  9. Outcome and structural integrity of rotator cuff after arthroscopic treatment of large and massive tears with double row technique: a 2-year followup.

    PubMed

    Carbonel, Ignacio; Martínez, Angel A; Aldea, Elisa; Ripalda, Jorge; Herrera, Antonio

    2013-01-01

    Purpose. The purpose of this study was to evaluate the functional outcome and the tendon healing after arthroscopic double row rotator cuff repair of large and massive rotator cuff tears. Methods. 82 patients with a full-thickness large and massive rotator cuff tear underwent arthroscopic repair with double row technique. Results were evaluated by use of the UCLA, ASES, and Constant questionnaires, the Shoulder Strength Index (SSI), and range of motion. Follow-up time was 2 years. Magnetic resonance imaging (MRI) studies were performed on each shoulder preoperatively and 2 years after repair. Results. 100% of the patients were followed up. UCLA, ASES, and Constant questionnaires showed significant improvement compared with preoperatively (P < 0.001). Range of motion and SSI in flexion, abduction, and internal and external rotation also showed significant improvement (P < 0.001). MRI studies showed 24 cases of tear after repair (29%). Only 8 cases were a full-thickness tear. Conclusions. At two years of followup, in large and massive rotator cuff tears, an arthroscopic double row rotator cuff repair technique produces an excellent functional outcome and structural integrity.

  10. Outcome and Structural Integrity of Rotator Cuff after Arthroscopic Treatment of Large and Massive Tears with Double Row Technique: A 2-Year Followup

    PubMed Central

    Carbonel, Ignacio; Martínez, Angel A.; Aldea, Elisa; Ripalda, Jorge

    2013-01-01

    Purpose. The purpose of this study was to evaluate the functional outcome and the tendon healing after arthroscopic double row rotator cuff repair of large and massive rotator cuff tears. Methods. 82 patients with a full-thickness large and massive rotator cuff tear underwent arthroscopic repair with double row technique. Results were evaluated by use of the UCLA, ASES, and Constant questionnaires, the Shoulder Strength Index (SSI), and range of motion. Follow-up time was 2 years. Magnetic resonance imaging (MRI) studies were performed on each shoulder preoperatively and 2 years after repair. Results. 100% of the patients were followed up. UCLA, ASES, and Constant questionnaires showed significant improvement compared with preoperatively (P < 0.001). Range of motion and SSI in flexion, abduction, and internal and external rotation also showed significant improvement (P < 0.001). MRI studies showed 24 cases of tear after repair (29%). Only 8 cases were a full-thickness tear. Conclusions. At two years of followup, in large and massive rotator cuff tears, an arthroscopic double row rotator cuff repair technique produces an excellent functional outcome and structural integrity. PMID:23533788

  11. Association of ACL tears and single nucleotide polymorphisms in the collagen 12 A1 gene in the Indian population - a preliminary case-control study

    PubMed Central

    John, Rakesh; Prabhakar, Sharad; Dhillon, Mandeep Singh; Anand, Akshay; Minhas, Gillipsie

    2016-01-01

    Summary Background Genetic predisposition to ACL tears has received tremendous interest in the past few years with many SNPs of different genes being linked to ACL tear. Study Objectives To examine if specific sequence variants in COL12A1 gene are associated with ACL tears in Indian population. Study design Case-control study. Materials and methods 50 patients with surgically diagnosed ACL tear and 52 healthy, age-matched controls without any ligament/tendon injuries were genotyped for rs970547 and rs240736 SNPs using real time PCR method. Results The AG and GG genotypes were significantly under-represented in study group patients in rs970547 region (p=0.0361). However, there was no significant difference in genotype/allele frequencies in the rs240736 region. Conclusions The COL12A1 rs970547 SNP is associated with ACL tears in the Indian population. However, these results need to be validated further so that predisposed individuals can be screened in the future for counselling and intervention. Level of evidence III PMID:27900301

  12. Tear film dynamics with evaporation and osmolarity

    NASA Astrophysics Data System (ADS)

    Siddique, Javed; Braun, Richard

    2011-11-01

    We consider a model problem for the evaporation and breakup up of tear film. The model includes the effects of surface tension, Marangoni stresses, insoluble surfactant transport, evaporation, osmolarity transport, osmosis and wetting of corneal surface. Evaporation is made dependent on surface concentration in order to mimic the lipid layer of the tear film when there is a single fluid layer in the model. In many cases for a single layer, the Marangoni effect seems to eliminate a localized area of increased evaporation due to reduced surfactant concentration. In this model the osmolarity in the tear film increases because of average evaporation rate rather than by a locally increased evaporation rate. If time permits, the effect of having a second fluid layer, representing the lipid layer, will be explored as well.

  13. Slab tears and intermediate-depth seismicity

    USGS Publications Warehouse

    Meighan, Hallie E.; Ten Brink, Uri; Pulliam, Jay

    2013-01-01

    Active tectonic regions where plate boundaries transition from subduction to strike slip can take several forms, such as triple junctions, acute, and obtuse corners. Well-documented slab tears that are associated with high rates of intermediate-depth seismicity are considered here: Gibraltar arc, the southern and northern ends of the Lesser Antilles arc, and the northern end of Tonga trench. Seismicity at each of these locations occurs, at times, in the form of swarms or clusters, and various authors have proposed that each marks an active locus of tear propagation. The swarms and clusters start at the top of the slab below the asthenospheric wedge and extend 30–60 km vertically downward within the slab. We propose that these swarms and clusters are generated by fluid-related embrittlement of mantle rocks. Focal mechanisms of these swarms generally fit the shear motion that is thought to be associated with the tearing process.

  14. [Tears' immunology in acute eye diseases].

    PubMed

    Ignat, F; Godeanu, L; Davidescu, L; Voiculescu, M

    2001-01-01

    The aim of the study is to research the immunoglobulins' concentration into the tears liquid and into the blood serum at the patients with acute affections of the anterior ocular pole. The study was accomplished on two groups of patients: one group with herpetic Keratitis, the other with anterior uveitis, the second having a different etiology--that the viral one. Another group of patients with senile cataract was used like witness-group. The immunoglobulins concentration were detected into the serum and into the tears by the Mancini method of the radial immunodiffusion. The results indicate a general immunodefficiency signed by the decrease of IgG and IgM into the serum on the one hand, and the increase of local defense mechanisms reflected on the growing of IgA and IgG level into the tears, on the other hand.

  15. Evaluation and treatment of rotator cuff tears.

    PubMed

    Lansdown, Drew A; Feeley, Brian T

    2012-05-01

    Rotator cuff injuries are common problems and a frequent reason for patients to present to primary care physicians. These injuries are seen more frequently now with the aging population. These muscles allow for movement of the arm in overhead activities and controlled movements through space. A thorough physical examination can lead to the diagnosis of rotator cuff pathology. Radiographic imaging may offer some insight into the underlying pathology, and magnetic resonance imaging provides for excellent visualization of the rotator cuff. Many rotator cuff tears, especially partial tears, will symptomatically improve with conservative management. Surgical treatment may offer improved pain relief and function in those patients for whom nonoperative care is insufficient. In cases in which rotator cuff repair is not possible, the reverse total shoulder arthroplasty is a possibility. New technologies are also under investigation that allow for biological augmentation of rotator cuff tears.

  16. Ruptured Tendons in Anabolic-Androgenic Steroid Users: A Cross-Sectional Cohort Study

    PubMed Central

    Kanayama, Gen; DeLuca, James; Meehan, William P.; Hudson, James I.; Isaacs, Stephanie; Baggish, Aaron; Weiner, Rory; Micheli, Lyle; Pope, Harrison G.

    2016-01-01

    Background Accumulating case reports have described tendon rupture in men using anabolic-androgenic steroids (AAS). However no controlled study, to our knowledge, has assessed history of tendon rupture in a large cohort of AAS users and comparison nonusers. Hypothesis We hypothesized that men reporting long-term AAS abuse would report an elevated lifetime incidence of tendon rupture as compared to non-AAS-using bodybuilders. Study Design Cross-sectional cohort study. Methods We obtained medical histories from 142 experienced male bodybuilders age 35–55, recruited in the course of two studies. Of these men, 88 reported at least two years of cumulative lifetime AAS use and 54 reported no history of AAS use. In men reporting a history of tendon rupture, we recorded circumstances of the injury, prodromal symptoms, concomitant drug or alcohol use, and details of current and lifetime AAS use if applicable. We also obtained surgical records for most participants. Results Nineteen (22%) of the AAS users, but only 3 (6%) of the nonusers reported at least one lifetime tendon rupture. The hazard ratio (95% confidence interval) for a first ruptured tendon in AAS users versus nonusers was 9.0 (2.5, 32.3); P <.001. Several men reported two or more independent lifetime tendon ruptures. Interestingly, upper body tendon ruptures occurred exclusively in the AAS group (15 [17%] of the AAS users versus 0 non-users; risk difference 0.17 (0.09, 0.25); P < 0.001 [hazard ratio not estimable]), whereas we found no significant difference between users and nonusers in risk for lower body ruptures (6 [7%] AAS users, 3 [6%] nonusers; hazard ratio 3.1 (0.7, 13.8), P = 0.13). Of 31 individual tendon ruptures that we assessed, only 6 (19%) occurred while weightlifting, with the majority occurring during other sports activities. Eight (26%) ruptures followed prodromal symptoms of nonspecific pain in the region. Virtually all ruptures were treated surgically with complete or near

  17. Bifurcated popliteus tendon: a descriptive arthroscopic study

    PubMed Central

    Ginés-Cespedosa, Albert; Monllau, Joan C.

    2008-01-01

    The objective of this study was to confirm the presence and frequency of a bifurcation of the popliteus tendon. The popliteus tendon has received attention due to its important function as a knee stabiliser. Several anatomical variants have recently been reported, one of them being a bifurcated tendon. However, the actual frequency as well as the possible role of this particular variant is still unknown. We prospectively analysed a series of 1,569 arthroscopies between January 2005 to December 2007. Six asymptomatic bifurcated popliteus tendons were found. No alterations in the magnetic resonance imaging were seen and no clinical signs (related to the popliteus tendon) were observed in these patients before surgery. In all cases the morphological variant was found by chance. Our results suggest that the presence of a bifurcated popliteus tendon is a fact and that its frequency, not previously reported, should not be ignored. PMID:18998130

  18. 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

  19. Comparison between surgery and physiotherapy in the treatment of small and medium-sized tears of the rotator cuff: A randomised controlled study of 103 patients with one-year follow-up.

    PubMed

    Moosmayer, S; Lund, G; Seljom, U; Svege, I; Hennig, T; Tariq, R; Smith, H-J

    2010-01-01

    In order to compare the outcome from surgical repair and physiotherapy, 103 patients with symptomatic small and medium-sized tears of the rotator cuff were randomly allocated to one of the two approaches. The primary outcome measure was the Constant score, and secondary outcome measures included the self-report section of the American Shoulder and Elbow Surgeons score, the Short Form 36 Health Survey and subscores for shoulder movement, pain, strength and patient satisfaction. Scores were taken at baseline and after six and 12 months by a blinded assessor. Nine patients (18%) with insufficient benefit from physiotherapy after at least 15 treatment sessions underwent secondary surgical treatment. Analysis of between-group differences showed better results for the surgery group on the Constant scale (difference 13.0 points, p - 0.002), on the American Shoulder and Elbow surgeons scale (difference 16.1 points, p < 0.0005), for pain-free abduction (difference 28.8 degrees , p = 0.003) and for reduction in pain (difference on a visual analogue scale -1.7 cm, p < 0.0005).

  20. On conjoining pressures in the tear film

    NASA Astrophysics Data System (ADS)

    Siddique, Javed; Gewecke, Nicholas; Braun, Rich

    2012-11-01

    We study the local tear film dynamics in a two-layer model with a Newtonian extensional layer over a Newtonian shear layer with a surfactant between. The upper layer represents the lipid layer and the underlying layer the aqueous layer in the tear film. We study the effect of the ions on the conjoining pressure in the aqueous layer using a Debye-Huckel approximation. If time permits, we will treat the evaporation of the water from the underlying aqueous layer and the effect of increasing osmolarity of the aqueous and the interaction with the conjoining pressure. More complicated conjoining pressure contributions are added as needed.

  1. Structure and function of tuna tail tendons.

    PubMed

    Shadwick, Robert E; Rapoport, H Scott; Fenger, Joelle M

    2002-12-01

    The caudal tendons in tunas and other scombrid fish link myotomal muscle directly to the caudal fin rays, and thus serve to transfer muscle power to the hydrofoil-like tail during swimming. These robust collagenous tendons have structural and mechanical similarity to tendons found in other vertebrates, notably the leg tendons of terrestrial mammals. Biochemical studies indicate that tuna tendon collagen is composed of the (alpha1)(2),alpha2 heterotrimer that is typical of vertebrate Type I collagen, while tuna skin collagen has the unusual alpha1,alpha2,alpha3 trimer previously described in the skin of some other teleost species. Tuna collagen, like that of other fish, has high solubility due to the presence of an acid-labile intermolecular cross-link. Unlike collagen in mammalian tendons, no differences related to cross-link maturation were detected among tendons in tuna ranging from 0.05 to 72 kg (approx. 0.25-6 years). Tendons excised post-mortem were subjected to load cycling to determine the modulus of elasticity and resilience (mean of 1.3 GPa and 90%, respectively). These material properties compare closely to those of leg tendons from adult mammals that can function as effective biological springs in terrestrial locomotion, but the breaking strength is substantially lower. Peak tendon forces recorded during steady swimming appear to impose strains of much less than 1% of tendon length, and no more than 1.5% during bursts. Thus, the caudal tendons in tunas do not appear to function as elastic storage elements, even at maximal swimming effort.

  2. ACL Tears on The Rise Among Kids, Especially Girls

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_163730.html ACL Tears on the Rise Among Kids, Especially Girls ... A common knee injury -- an anterior cruciate ligament (ACL) tear -- has steadily increased among 6- to 18- ...

  3. Rotator cuff tear: physical examination and conservative treatment.

    PubMed

    Itoi, Eiji

    2013-03-01

    Rotator cuff tear is one of the most common shoulder diseases. It is interesting that some rotator cuff tears are symptomatic, whereas others are asymptomatic. Pain is the most common symptom of patients with a tear. Even in patients with an asymptomatic tear, it may become symptomatic with an increase in tear size. Physical examination is extremely important to evaluate the presence, location, and extent of a tear. It also helps us to understand the mechanism of pain. Conservative treatment often works. Patients with well-preserved function of the supraspinatus and infraspinatus are the best candidates for conservative treatment. After a successful conservative treatment, the symptom once disappeared may come back again. This recurrence of symptoms is related to tear expansion. Those with high risk of tear expansion and those with less functional rotator cuff muscles are less likely to respond to conservative treatment. They may need a surgical treatment.

  4. Retinal Pigment Epithelium Tears: Risk Factors, Mechanism and Therapeutic Monitoring.

    PubMed

    Clemens, Christoph R; Eter, Nicole

    2016-01-01

    Tears of the retinal pigment epithelium (RPE) are most commonly associated with vascularised RPE detachment due to age-related macular degeneration (AMD), and they usually involve a deleterious loss in visual acuity. Recent studies suggest an increase in RPE tear incidences since the introduction of anti-vascular endothelial growth factor (anti-VEGF) therapies as well as a temporal association between the tear event and the intravitreal injection. As the number of AMD patients and the number of administered anti-VEGF injections increase, both the challenge of RPE tear prevention and the treatment after RPE tear formation have become more important. At the same time, the evolution of retinal imaging has significantly contributed to a better understanding of RPE tear development in recent years. This review summarises the current knowledge on RPE tear development, predictive factors, and treatment strategies before and after RPE tear formation.

  5. [Effects of Gravity on Attachment of Tendon to Bone

    NASA Technical Reports Server (NTRS)

    Johnson, Roger B.

    1997-01-01

    We have received and processed all samples for either light or scanning electron microscopic analysis and have completed the histomorphometric analysis. We have characterized the changes caused by spaceflight to tendon attachments to the calcaneus, tibia, fibula and femur and compared them to hindlimbs and forelimbs from NIH.RZ. Soleus muscle histomorphometry has also been completed. Our results suggest severe osteoporosis in the femur, fibula and tibia of animals coincident to spaceflight, which had not resolved after 4-5 days following return to earth. This was evident at all sites, including sites of tendon attachments. This atrophy was not evident in the calcaneus. No muscle atrophy was evident. Comparison of scanning photomicrographs of flight animals with other lactating animals demonstrated structural similarities and suggested that it might be worthwhile to assess whether lactation is a factor in development of the osteoporosis in the spaceflight animals. In addition, evaluation of total calcium utilization by spaceflight animals would be beneficial.

  6. 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

  7. Magnetotail dynamics excited by the streaming tearing mode

    NASA Technical Reports Server (NTRS)

    Sato, T.; Walker, R. J.

    1982-01-01

    Magnetotail reconnection in the presence of plasma streaming parallel to the neutral sheet is modeled. The tearing mode is excited much more violently in the case with parallel plasma flow in the plasma sheet than in the case with no flow. The flow patterns for the nonlinear resistive tearing mode and the streaming tearing mode are much more complex than those for the linear tearing mode. Flow vortices are observed in both cases.

  8. 49 CFR 173.340 - Tear gas devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Tear gas devices. 173.340 Section 173.340... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.340 Tear gas devices. (a) Packagings for tear gas devices must be approved prior to initial transportation by the Associate Administrator....

  9. 49 CFR 173.340 - Tear gas devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Tear gas devices. 173.340 Section 173.340... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.340 Tear gas devices. (a) Packagings for tear gas devices must be approved prior to initial transportation by the Associate Administrator....

  10. 49 CFR 173.340 - Tear gas devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Tear gas devices. 173.340 Section 173.340... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.340 Tear gas devices. (a) Packagings for tear gas devices must be approved prior to initial transportation by the Associate Administrator....

  11. Passive mechanical properties of human gastrocnemius muscle tendon units, muscle fascicles and tendons in vivo.

    PubMed

    Hoang, P D; Herbert, R D; Todd, G; Gorman, R B; Gandevia, S C

    2007-12-01

    This study provides the first in vivo measures of the passive length-tension properties of relaxed human muscle fascicles and their tendons. A new method was used to derive passive length-tension properties of human gastrocnemius muscle-tendon units from measures of ankle stiffness obtained at a range of knee angles. Passive length-tension curves of the muscle-tendon unit were then combined with ultrasonographic measures of muscle fascicle length and pennation to determine passive length-tension curves of the muscle fascicles and tendons. Mean slack lengths of the fascicles, tendons and whole muscle-tendon units were 3.3+/-0.5 cm, 39.5+/-1.6 cm and 42.3+/-1.5 cm, respectively (means +/- s.d., N=6). On average, the muscle-tendon units were slack (i.e. their passive tension was zero) over the shortest 2.3+/-1.2 cm of their range. With combined changes of knee and ankle angles, the maximal increase in length of the gastrocnemius muscle-tendon unit above slack length was 6.7+/-1.9 cm, of which 52.4+/-11.7% was due to elongation of the tendon. Muscle fascicles and tendons underwent strains of 86.4+/-26.8% and 9.2+/-4.1%, respectively, across the physiological range of lengths. We conclude that the relaxed human gastrocnemius muscle-tendon unit falls slack over about one-quarter of its in vivo length and that muscle fascicle strains are much greater than tendon strains. Nonetheless, because the tendons are much longer than the muscle fascicles, tendons contribute more than half of the total compliance of the muscle-tendon unit.

  12. Tension-free cuff repairs with excision of macroscopic tendon lesions and muscular advancement: results in a prospective series with limited fatty muscular degeneration.

    PubMed

    Goutallier, D; Postel, J M; Van Driessche, S; Godefroy, D; Radier, C

    2006-01-01

    Recurrent tears after rotator cuff repairs are frequent. These could be influenced by excessive tension on a degenerated tendinous stump and by fatty degeneration of the cuff muscles. The goal of this study was to evaluate the anatomic and functional results of tension-free cuff repairs with the excision of macroscopic tendon lesions in a series with limited muscular fatty degeneration of the infraspinatus and a global fatty degeneration index of rotator cuff muscles equal to or lower than 2. We studied 27 tears, comprising 13 cases involving both supraspinatus and infraspinatus tears, 13 cases with 3-tendon tears, and 1 case with only a supraspinatus tear. All shoulders were operated on through a transacromial approach easily repaired with 2 titanium screws with washers. To obtain a repair without tension, a single advancement was performed in 20 cases and a double advancement of both the supraspinatus and infraspinatus was done in 7 cases. The shoulders were evaluated clinically preoperatively and postoperatively with the non-weighted Constant score and anatomically with computed arthrotomography scans. The mean age at operation was 59.5 years, and the length of follow-up ranged from 1 to 4 years. Of the cuffs, 23 (85%) were watertight 1 year after surgery. No predictive factor of retear could be found. The functional improvement was statistically significant only for watertight cuffs, with an improvement of the Constant score from 57.8 to 75. The only predictive factor of functional outcome in this watertight group was the preoperative Constant score. Single and double advancements yielded similar functional results regardless of the extent of the initial tear, provided that the cuff was watertight at revision.

  13. 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.

  14. Use of stem cells and growth factors in rotator cuff tendon repair.

    PubMed

    Akyol, Engin; Hindocha, Sandip; Khan, Wasim S

    2015-01-01

    In this review, we analysed the role of stem cell and growth factor therapy on rotator cuff tendon repair. The injury to the rotator cuff tendons can be sustained in numerous ways and generally causes significant pain and disability to the affected individual. Following surgical repair of ruptured rotator cuff tendons re-rupture rates can be as high as 20-60%. In order to augment this repair process and to decrease the re-rupture rates tissue engineering methods can be used. These include the use of stem cells and growth factors. Mesenchymal stem cells are stem cells which can differentiate into a variety of connective tissue cell types and can therefore be utilised in repairing tendons. So far there has only been one human study using stem cells in rotator cuff tendon repair. This study has produced a positive result but consisted of only 14 patients and lacks a control group for comparison. Similar work has also been done using growth factors. Both individual and combination growth factor therapy have been used to improve rotator cuff tendon repair. However, the results so far have been disappointing with growth factors. For the purpose of future studies better techniques should be explored with regards to the delivery of stem cells and growth factors as well as the possibility of combining growth factor and stem cell therapy to improve repair rates.

  15. 49 CFR 178.818 - Tear test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... IBC design types. (b) Special preparation for the tear test. The flexible IBC must be filled to not... the bottom surface and the top level of the contents. The IBC must then be subjected to a uniformly... five minutes. An IBC which is designed to be lifted from the top or the side must, after removal of...

  16. Tearing mode analysis in tokamaks, revisited

    SciTech Connect

    Nishimura, Y.; Callen, J.D.; Hegna, C.C.

    1997-12-01

    A new {Delta}{prime} shooting code has been developed to investigate tokamak plasma tearing mode stability in a cylinder and large aspect ratio ({epsilon} {le} 0.25) toroidal geometries, neglecting toroidal mode coupling. A different computational algorithm is used (shooting out from the singular surface instead of into it) to resolve the strong singularities at the mode rational surface, particularly in the presence of finite pressure term. Numerical results compare favorably with Furth et al. results. The effects of finite pressure, which are shown to decrease {Delta}{prime}, are discussed. It is shown that the distortion of the flux surfaces by the Shafranov shift, which modifies the geometry metric element stabilizes the tearing mode significantly, even in a low {beta} regime before the toroidal magnetic curvature effects come into play. Double tearing modes in toroidal geometries are examined as well. Furthermore, m {ge} 2 tearing mode stability criteria are compared with three dimensional initial value MHD simulation by the FAR code.

  17. Immunoglobulins in tears of normal Indian people.

    PubMed Central

    Sen, D. K.; Sarin, G. S.; Mani, K.; Saha, K.

    1976-01-01

    Immunoglobulin concentrations in tears from 50 healthy Indians aged from 14 to 50 years were measured by a standard immunodiffusion method. The levels of IgA were substantial; those of IgG were very low; and IgD and IgM were not present. The mean IgA level was 24-6 mg/100 ml. PMID:1276121

  18. 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.

  19. Water-evaporation reduction by duplex films: application to the human tear film.

    PubMed

    Cerretani, Colin F; Ho, Nghia H; Radke, C J

    2013-09-01

    Water-evaporation reduction by duplex-oil films is especially important to understand the physiology of the human tear film. Secreted lipids, called meibum, form a duplex film that coats the aqueous tear film and purportedly reduces tear evaporation. Lipid-layer deficiency is correlated with the occurrence of dry-eye disease; however, in-vitro experiments fail to show water-evaporation reduction by tear-lipid duplex films. We review the available literature on water-evaporation reduction by duplex-oil films and outline the theoretical underpinnings of spreading and evaporation kinetics that govern behavior of these systems. A dissolution-diffusion model unifies the data reported in the literature and identifies dewetting of duplex films into lenses as a key challenge to obtaining significant evaporation reduction. We develop an improved apparatus for measuring evaporation reduction by duplex-oil films including simultaneous assessment of film coverage, stability, and temperature, all under controlled external mass transfer. New data reported in this study fit into the larger body of work conducted on water-evaporation reduction by duplex-oil films. Duplex-oil films of oxidized mineral oil/mucin (MOx/BSM), human meibum (HM), and bovine meibum (BM) reduce water evaporation by a dissolution-diffusion mechanism, as confirmed by agreement between measurement and theory. The water permeability of oxidized-mineral-oil duplex films agrees with those reported in the literature, after correction for the presence of mucin. We find that duplex-oil films of bovine and human meibum at physiologic temperature reduce water evaporation only 6-8% for a 100-nm film thickness pertinent to the human tear film. Comparison to in-vivo human tear-evaporation measurements is inconclusive because evaporation from a clean-water surface is not measured and because the mass-transfer resistance is not characterized.

  20. Evaporation-driven instability of the precorneal tear film.

    PubMed

    Peng, Cheng-Chun; Cerretani, Colin; Braun, Richard J; Radke, C J

    2014-04-01

    Tear-film instability is widely believed to be a signature of eye health. When an interblink is prolonged, randomly distributed ruptures occur in the tear film. "Black spots" and/or "black streaks" appear in 15 to 40 s for normal individuals. For people who suffer from dry eye, tear-film breakup time (BUT) is typically less than a few seconds. To date, however, there is no satisfactory quantitative explanation for the origin of tear rupture. Recently, it was proposed that tear-film breakup is related to locally high evaporative thinning. A spatial variation in the thickness of the tear-film lipid layer (TFLL) may lead to locally elevated evaporation and subsequent tear-film breakup. We examine the local-evaporation-driven tear-film-rupture hypothesis in a one-dimensional (1-D) model for the evolution of a thin aqueous tear film overriding the cornea subject to locally elevated evaporation at its anterior surface and osmotic water influx at its posterior surface. Evaporation rate depends on mass transfer both through the coating lipid layer and through ambient air. We establish that evaporation-driven tear-film breakup can occur under normal conditions but only for higher aqueous evaporation rates. Predicted roles of environmental conditions, such as wind speed and relative humidity, on tear-film stability agree with clinical observations. More importantly, locally elevated evaporation leads to hyperosmolar spots in the tear film and, hence, vulnerability to epithelial irritation. In addition to evaporation rate, tear-film instability depends on the strength of healing flow from the neighboring region outside the breakup region, which is determined by the surface tension at the tear-film surface and by the repulsive thin-film disjoining pressure. This study provides a physically consistent and quantitative explanation for the formation of black streaks and spots in the human tear film during an interblink.

  1. Single-stage reconstruction of flexor tendons with vascularized tendon transfers.

    PubMed

    Cavadas, P C; Pérez-García, A; Thione, A; Lorca-García, C

    2015-03-01

    The reconstruction of finger flexor tendons with vascularized flexor digitorum superficialis (FDS) tendon grafts (flaps) based on the ulnar vessels as a single stage is not a popular technique. We reviewed 40 flexor tendon reconstructions (four flexor pollicis longus and 36 finger flexors) with vascularized FDS tendon grafts in 38 consecutive patients. The donor tendons were transferred based on the ulnar vessels as a single-stage procedure (37 pedicled flaps, three free flaps). Four patients required composite tendon and skin island transfer. Minimum follow-up was 12 months, and functional results were evaluated using a total active range of motion score. Multiple linear regression analysis was performed to evaluate the factors that could be associated with the postoperative total active range of motion. The average postoperative total active range of motion (excluding the thumbs) was 178.05° (SD 50°). The total active range of motion was significantly lower for patients who were reconstructed with free flaps and for those who required composite tendon and skin island flap. Age, right or left hand, donor/motor tendon and pulley reconstruction had no linear effect on total active range of motion. Overall results were comparable with a published series on staged tendon grafting but with a lower complication rate. Vascularized pedicled tendon grafts/flaps are useful in the reconstruction of defects of finger flexor tendons in a single stage, although its role in the reconstructive armamentarium remains to be clearly established.

  2. Arthroscopic treatment options for irreparable rotator cuff tears of the shoulder

    PubMed Central

    Anley, Cameron M; Chan, Samuel KL; Snow, Martyn

    2014-01-01

    The management of patients with irreparable rotator cuff tears remains a challenge for orthopaedic surgeons with the final treatment option in many algorithms being either a reverse shoulder arthroplasty or a tendon transfer. The long term results of these procedures are however still widely debated, especially in younger patients. A variety of arthroscopic treatment options have been proposed for patients with an irreparable rotator cuff tear without the presence of arthritis of the glenohumeral joint. These include a simple debridement with or without a biceps tenotomy, partial rotator cuff repair with or without an interval slide, tuberplasty, graft interposition of the rotator cuff, suprascapular nerve ablation, superior capsule reconstruction and insertion of a biodegradable spacer (Inspace) to depress the humeral head. These options should be considered as part of the treatment algorithm in patients with an irreparable rotator cuff and could be used as either as an interim procedure, delaying the need for more invasive surgery in the physiologically young and active, or as potential definitive procedures in the medically unfit. The aim of this review is to highlight and summarise arthroscopic procedures and the results thereof currently utilised in the management of these challenging patients. PMID:25405083

  3. Effects of Mold Temperature and Pouring Temperature on the Hot Tearing of Cast Al-Cu Alloys

    NASA Astrophysics Data System (ADS)

    Li, Shimin; Sadayappan, Kumar; Apelian, Diran

    2016-10-01

    The effects of mold temperature and pouring temperature on hot tearing formation and contraction behavior of a modified Al-Cu alloy 206 (M206) have been studied. The experiments were conducted using a newly developed Constrained Rod Mold, which simultaneously measures the contraction force/time/temperature during solidification for the restrained casting or linear contraction/time/temperature for a relaxed casting. Three mold temperatures [473 K, 573 K, and 643 K (200 °C, 300 °C, and 370 °C)] and three pouring temperatures [superheat of 50 K, 100 K, and 150 K (50 °C, 100 °C, and 150 °C)] were studied, and alloy A356 was used as reference for comparison. The results confirm that alloy A356 has high resistance to hot tearing. Hot tearing did not occur for the three mold temperatures evaluated, whereas alloy M206 exhibited significant hot tearing for the same casting and mold temperature conditions. Hot tearing severity and linear contraction in alloy 206 decreased significantly with increasing mold temperature. Increasing pouring temperature increases hot tearing in alloy M206, but the effect is not as significant as that of mold temperature. The results and underlying mechanism of these effects are discussed in correlation with the thermomechanical properties and microstructures.

  4. Calcific tendonitis of the tibialis posterior tendon at the navicular attachment

    PubMed Central

    Harries, Luke; Kempson, Susan; Watura, Roland

    2011-01-01

    Calcific tendinosis (tendonosis/tendonitis) is a condition which results from the deposition of calcium hydroxyapatite crystals in any tendon of the body. Calcific tendonitis usually presents with pain, which can be exacerbated by prolonged use of the affected tendon. We report a case of calcific tendinosis in the posterior tibialis tendon at the navicular insertion. The pathology is rare in the foot, and extremely rare in the tibialis posterior tendon, indeed there are only 2 reported in the published literature. This case report highlights the need to consider calcific tendinosis in the foot despite its rarity. If this diagnosis is considered early, appropriate investigations can then be requested and unnecessary biopsies, use of antibiotics and surgery can be avoided. We also discuss possible causes of calcific tendinosis in the tibialis posterior tendon, the role of imaging modalities and review treatment methods. PMID:22470798

  5. 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.

  6. Normal tear protein profiles and age-related changes.

    PubMed Central

    McGill, J I; Liakos, G M; Goulding, N; Seal, D V

    1984-01-01

    The specific and non-specific tear proteins have been analysed by means of the ELISA technique to establish the normal and age-related values. There is a linear and related decline of lysozyme and lactoferrin with age, and a similar but unrelated reduction in tear volume. IgA levels gradually decline, while caeruloplasmin and IgG both increase after the fifth decade. The results suggest that tear IgG and caeruloplasmin are probably transudates from the serum, that IgA is secreted independently of tear volume, and that lysozyme and lactoferrin are secreted at the same site but independently of tear volume. PMID:6712908

  7. Treatment of non-traumatic rotator cuff tears: A randomised controlled trial with one-year clinical results.

    PubMed

    Kukkonen, J; Joukainen, A; Lehtinen, J; Mattila, K T; Tuominen, E K J; Kauko, T; Aärimaa, V

    2014-01-01

    We have compared three different methods of treating symptomatic non-traumatic tears of the supraspinatus tendon in patients above 55 years of age. A total of 180 shoulders (173 patients) with supraspinatus tendon tears were randomly allocated into one of three groups (each of 60 shoulders); physiotherapy (group 1), acromioplasty and physiotherapy (group 2) and rotator cuff repair, acromioplasty and physiotherapy (group 3). The Constant score was assessed and followed up by an independent observer pre-operatively and at three, six and twelve months after the intervention. Of these, 167 shoulders were available for assessment at one year (follow-up rate of 92.8%). There were 55 shoulders in group 1 (24 in males and 31 in females, mean age 65 years (55 to 79)), 57 in group 2 (29 male and 28 female, mean age 65 years (55 to 79)) and 55 shoulders in group 3 (26 male and 29 female, mean age 65 years (55 to 81)). There were no between-group differences in the Constant score at final follow-up: 74.1 (sd 14.2), 77.2 (sd 13.0) and 77.9 (sd 12.1) in groups 1, 2 and 3, respectively (p = 0.34). The mean change in the Constant score was 17.0, 17.5, and 19.8, respectively (p = 0.34). These results suggest that at one-year follow-up, operative treatment is no better than conservative treatment with regard to non-traumatic supraspinatus tears, and that conservative treatment should be considered as the primary method of treatment for this condition.

  8. Duplication of the extensor carpi ulnaris tendon.

    PubMed

    Barfred, T; Adamsen, S

    1986-05-01

    Three cases are presented, in which an anomalous tendon slip between the extensor carpi ulnaris tendon and the extensor apparatus of the fifth finger was found. One of the patients was a violinist, who had serious impairment of the left wrist joint and the small finger due to the anomaly. The symptoms disappeared after excision.

  9. 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.

  10. Temporal features of human tendon vibration illusions.

    PubMed

    Fuentes, Christina T; Gomi, Hiroaki; Haggard, Patrick

    2012-12-01

    Muscle spindles provide information about the position and movement of our bodies. One method for investigating spindle signals is tendon vibration. Vibration of flexor tendons can produce illusions of extension, and vibration of extensor tendons can produce illusions of flexion. Here we estimate the temporal resolution and persistence of these illusions. In Experiments 1 and 2, sequences of alternating vibration of wrist flexor and extensor tendons produced position illusions that varied with alternation period. When vibrations alternated at 1 Hz or slower, perceived position at the end of the sequence depended on the last vibration. When vibrations alternated every 0.3 s, perceived position was independent of the last vibration. Experiment 2 verified and extended these results using more trials and concurrent electromyographic recording. Although tendon vibrations sometimes induce reflexive muscle activity, we found no evidence that such activity contributed to these effects. Experiment 3 investigated how long position sense is retained when not updated by current information from spindles. Our first experiments suggested that vibrating antagonistic tendons simultaneously could produce conflicting inputs, leaving position sense reliant on memory of position prior to vibration onset. We compared variability in position sense after different durations of such double vibration. After 12 s of double vibration, variability across trials exceeded levels predicted from vibrations of flexor or extensor tendons alone. This suggests that position sense memory had decayed too much to substitute for the current conflicting sensory information. Together, our results provide novel, quantitative insight into the temporal properties of tendon vibration illusions.

  11. Acellular and glutaraldehyde-preserved tendon allografts for reconstruction of superficial digital flexor tendon in bovines: Part I--Clinical, radiological and angiographical observations.

    PubMed

    Ramesh, R; Kumar, N; Sharma, A K; Maiti, S K; Singh, G R

    2003-12-01

    Sixteen tenorrhaphies were performed at the mid-metatarsal region in eight buffalo calves under lignocaine epidural analgesia. A 2 cm long gap was created in the superficial digital flexor (SDF) tendon and immediately repaired with acellular grafts in animals of group I, 1% glutaraldehyde-preserved tendon allografts in group II. In group III, the defect was repaired with autografts. This group served as control. The contralateral limb in each animal was operated after an interval of 60 days and the animals underwent the same procedure according to the designed groups. Diclofenac sodium and Enrofloxacin was given post-operatively for 5 days. Clinical examination revealed significant increase (P < 0.05) in rectal temperature, heart and respiratory rate for 3-4 postoperative days in all the animals. Mild pain and exudation as well as early restoration of tendon gliding movements and weight-bearing were observed earlier in group I in comparison with group II. Air-tendograms revealed early organization, minimal adhesion formation and lesser thickening of tendon at the reconstructive site in the acellular group whereas in the glutaraldehyde group dense homogenous swelling with adhesions was seen along the flexors. Angiography on day 30 showed that the area of proximal and distal host tendon graft junction appeared hypervascularized, whereas the area occupied by the graft appeared relatively less vascularized. Normal vascularization was observed on day 90 in all the three groups.

  12. 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

  13. 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.

  14. 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.

  15. The Role of Detraining in Tendon Mechanobiology

    PubMed Central

    Frizziero, Antonio; Salamanna, Francesca; Della Bella, Elena; Vittadini, Filippo; Gasparre, Giuseppe; Nicoli Aldini, Nicolò; Masiero, Stefano; Fini, Milena

    2016-01-01

    Introduction: Several conditions such as training, aging, estrogen deficiency and drugs could affect the biological and anatomo-physiological characteristics of the tendon. Additionally, recent preclinical and clinical studies examined the effect of detraining on tendon, showing alterations in its structure and morphology and in tenocyte mechanobiology. However, few data evaluated the importance that cessation of training might have on tendon. Basically, we do not fully understand how tendons react to a phase of training followed by sudden detraining. Therefore, within this review, we summarize the studies where tendon detraining was examined. Materials and Methods: A descriptive systematic literature review was carried out by searching three databases (PubMed, Scopus and Web of Knowledge) on tendon detraining. Original articles in English from 2000 to 2015 were included. In addition, the search was extended to the reference lists of the selected articles. A public reference manager (www.mendeley.com) was adopted to remove duplicate articles. Results: An initial literature search yielded 134 references (www.pubmed.org: 53; www.scopus.com: 11; www.webofknowledge.com: 70). Fifteen publications were extracted based on the title for further analysis by two independent reviewers. Abstracts and complete articles were after that reviewed to evaluate if they met inclusion criteria. Conclusions: The revised literature comprised four clinical studies and an in vitro and three in vivo reports. Overall, the results showed that tendon structure and properties after detraining are compromised, with an alteration in the tissue structural organization and mechanical properties. Clinical studies usually showed a lesser extent of tendon alterations, probably because preclinical studies permit an in-depth evaluation of tendon modifications, which is hard to perform in human subjects. In conclusion, after a period of sudden detraining (e.g., after an injury), physical activity should

  16. 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

  17. Is higher serum cholesterol associated with altered tendon structure or tendon pain? A systematic review

    PubMed Central

    Tilley, Benjamin J; Cook, Jill L; Docking, Sean I; Gaida, James E

    2015-01-01

    Background Tendon pain occurs in individuals with extreme cholesterol levels (familial hypercholesterolaemia). It is unclear whether the association with tendon pain is strong with less extreme elevations of cholesterol. Objective To determine whether lipid levels are associated with abnormal tendon structure or the presence of tendon pain. Methods We conducted a systematic review and meta-analysis. Relevant articles were found through an electronic search of 6 medical databases—MEDLINE, Cochrane, AMED, EMBASE, Web of Science and Scopus. We included all case–control or cross-sectional studies with data describing (1) lipid levels or use of lipid-lowering drugs and (2) tendon structure or tendon pain. Results 17 studies (2612 participants) were eligible for inclusion in the review. People with altered tendon structure or tendon pain had significantly higher total cholesterol, low-density lipoprotein cholesterol and triglycerides, as well as lower high-density lipoprotein cholesterol; with mean difference values of 0.66, 1.00, 0.33, and −0.19 mmol/L, respectively. Conclusions The results of this review indicate that a relationship exists between an individual’s lipid profile and tendon health. However, further longitudinal studies are required to determine whether a cause and effect relationship exists between tendon structure and lipid levels. This could lead to advancement in the understanding of the pathoaetiology and thus treatment of tendinopathy. PMID:26474596

  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. Coupled thermal stress simulations of ductile tearing

    DOE PAGES

    Neilsen, Michael K.; Dion, Kristin

    2016-03-01

    Predictions for ductile tearing of a geometrically complex Ti-6Al-4V plate were generated using a Unified Creep Plasticity Damage model in fully coupled thermal stress simulations. Uniaxial tension and butterfly shear tests performed at displacement rates of 0.0254 and 25.4 mm/s were also simulated. Results from these simulations revealed that the material temperature increase due to plastic work can have a dramatic effect on material ductility predictions in materials that exhibit little strain hardening. Furthermore, this occurs because the temperature increase causes the apparent hardening of the material to decrease which leads to the initiation of deformation localization and subsequent ductilemore » tearing earlier in the loading process.« less

  20. Coupled thermal stress simulations of ductile tearing

    SciTech Connect

    Neilsen, Michael K.; Dion, Kristin

    2016-03-01

    Predictions for ductile tearing of a geometrically complex Ti-6Al-4V plate were generated using a Unified Creep Plasticity Damage model in fully coupled thermal stress simulations. Uniaxial tension and butterfly shear tests performed at displacement rates of 0.0254 and 25.4 mm/s were also simulated. Results from these simulations revealed that the material temperature increase due to plastic work can have a dramatic effect on material ductility predictions in materials that exhibit little strain hardening. Furthermore, this occurs because the temperature increase causes the apparent hardening of the material to decrease which leads to the initiation of deformation localization and subsequent ductile tearing earlier in the loading process.

  1. Tearing mode analysis in tokamaks, revisited

    SciTech Connect

    Nishimura, Y.; Callen, J.D.; Hegna, C.C.

    1998-12-01

    A new {Delta}{sup {prime}} shooting code has been developed to investigate tokamak plasma tearing mode stability in a cylinder and large aspect ratio ({epsilon}{le}0.25) toroidal geometries, neglecting toroidal mode coupling. A different computational algorithm is used (shooting out from the singular surface instead of into it) to resolve the strong singularities at the mode rational surface, particularly in the presence of the finite pressure term. Numerical results compare favorably with Furth {ital et al.} [H. P. Furth {ital et al.}, Phys. Fluids {bold 16}, 1054 (1973)] results. The effects of finite pressure, which are shown to decrease {Delta}{sup {prime}}, are discussed. It is shown that the distortion of the flux surfaces by the Shafranov shift, which modifies the geometry metric elements, stabilizes the tearing mode significantly, even in a low-{beta} regime before the toroidal magnetic curvature effects come into play. {copyright} {ital 1998 American Institute of Physics.}

  2. Immunoglobulins in tear in trachoma patients.

    PubMed Central

    Sen, D. K.; Sarin, G. S.; Saha, K.

    1977-01-01

    Tear immunoglobulin concentrations have been measured in 100 healthy people and 62 patients in different stages of trachoma. In healthy people the average IgA level was 27-8 mg/100 ml. There was no significant difference in the IgA level in various age groups and between the sexes. IgG was detected in 92 samples, and it was less than 1 mg/100 ml. IgM in tears was detected in only one sample. IgD was not detected in any specimen. In tracoma cases, the mean IgA level was found to be significantly lower (22-0 mg/100 ml) than in healthy people. There was no significant difference in IgA level between different stages of trachoma, IgG, IgD, and IgM could not be detected in any sample from the trachoma cases. PMID:856248

  3. Bladder tear during revision total hip arthroplasty.

    PubMed

    Grauer, Jonathan N; Halim, Andrea; Keggi, Kristaps J

    2014-08-01

    Total hip arthroplasty (THA) and revision total hip arthroplasty are among the most commonly performed orthopedic procedures. There are many reported complications of THA, but intrapelvic complications are a rare subset. Bladder injuries have infrequently been described in association with this common procedure. We present an unusual case of a bladder tear occurring intraoperatively during a revision THA. It is suspected that the patient's history of multiple prior hip procedures caused adhesions of the bladder to the pelvic floor and predisposed the bladder to injury during acetabular revision. Previous reports of bladder injury relating to THA have described thermal necrosis, component migration, and occasional direct perforation. There are no prior case reports describing bladder tears related to adhesions occurring intraoperatively during revision THA. This case report highlights the importance of surgeon awareness of an unusual complication. In this case, intraoperative and postoperative recognition of a hematuria diagnosis led to the appropriate treatment, and this patient had an acceptable outcome.

  4. Over the counter (OTC) artificial tear drops for dry eye syndrome

    PubMed Central

    Pucker, Andrew D; Ng, Sueko M; Nichols, Jason J

    2016-01-01

    Background Over the counter (OTC) artificial tears historically have been the first line of treatment for dry eye syndrome and dry eye-related conditions like contact lens discomfort, yet currently we know little regarding the overall efficacy of individual, commercially available artificial tears. This review provides a much needed meta-analytical look at all randomized and quasi-randomized clinical trials that have analyzed head-to-head comparisons of OTC artificial tears. Objectives To evaluate the effectiveness and toxicity of OTC artificial tear applications in the treatment of dry eye syndrome compared with another class of OTC artificial tears, no treatment, or placebo. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2015, Issue 12), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to December 2015), EMBASE (January 1980 to December 2015), Latin American and Caribbean Health Sciences (LILACS) (January 1982 to December 2015), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en) and the US Food and Drugs Administration (FDA) website (www.fda.gov). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 4 December 2015. We searched reference lists of included trials for any additional trials not identified by the electronic searches. Selection criteria This review includes randomized controlled trials with adult participants who were diagnosed with dry eye, regardless of race and gender. We included trials in which the age of participants was not reported, and clinical trials comparing OTC artificial tears with another class of OTC artificial tears, placebo, or no treatment. This review did not

  5. Proprioceptive deficit in patients with complete tearing of the anterior cruciate ligament☆☆☆

    PubMed Central

    Godinho, Pedro; Nicoliche, Eduardo; Cossich, Victor; de Sousa, Eduardo Branco; Velasques, Bruna; Salles, José Inácio

    2014-01-01

    Objective To investigate the existence of proprioceptive deficits between the injured limb and the uninjured (i.e. contralateral normal) limb, in individuals who suffered complete tearing of the anterior cruciate ligament (ACL), using a strength reproduction test. Methods Sixteen patients with complete tearing of the ACL participated in the study. A voluntary maximum isometric strength test was performed, with reproduction of the muscle strength in the limb with complete tearing of the ACL and the healthy contralateral limb, with the knee flexed at 60°. The meta-intensity was used for the procedure of 20% of the voluntary maximum isometric strength. The proprioceptive performance was determined by means of absolute error, variable error and constant error values. Results Significant differences were found between the control group and ACL group for the variables of absolute error (p = 0.05) and constant error (p = 0.01). No difference was found in relation to variable error (p = 0.83). Conclusion Our data corroborate the hypothesis that there is a proprioceptive deficit in subjects with complete tearing of the ACL in an injured limb, in comparison with the uninjured limb, during evaluation of the sense of strength. This deficit can be explained in terms of partial or total loss of the mechanoreceptors of the ACL. PMID:26229870

  6. 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.

  7. 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

  8. Tear Dysfunction and the Cornea: LXVII Edward Jackson Memorial Lecture

    PubMed Central

    Pflugfelder, Stephen C.

    2011-01-01

    Purpose To describe the cause and consequence of tear dysfunction related corneal disease. Design Perspective on effects of tear dysfunction on the cornea Methods Evidence is presented on the effects of tear dysfunction on corneal morphology, function and health, as well as efficacy of therapies for tear dysfunction related corneal disease. Results Tear dysfunction is a prevalent eye disease and the most frequent cause for superficial corneal epithelial disease that results in corneal barrier disruption, an irregular optical surface, light scattering, optical aberrations and exposure and sensitization of pain sensing nerve endings (nociceptors). Tear dysfunction related corneal disease causes irritation and visual symptoms, such as photophobia, blurred and fluctuating vision that may decrease quality of life. Dysfunction of one or more components of the lacrimal functional unit results in changes in tear composition, including elevated osmolarity and increased concentrations of matrix metalloproteinases, inflammatory cytokines and chemokines. These tear compositional changes promote disruption of tight junctions, alter differentiation and accelerate death of corneal epithelial cells. Conclusions Corneal epithelial disease resulting from tear dysfunction causes eye irritation and decreases visual function. Clinical and basic research has improved understanding of the pathogenesis of tear dysfunction related corneal epithelial disease, as well as treatment outcomes. PMID:22019306

  9. Characterization of ocular gland morphology and tear composition of pinnipeds

    PubMed Central

    Davis, Robin Kelleher; Doane, Marshall G.; Knop, Erich; Knop, Nadja; Dubielzig, Richard R.; Colitz, Carmen M. H.; Argüeso, Pablo; Sullivan, David A.

    2012-01-01

    Objective The importance of tear film integrity to ocular health in terrestrial mammals is well established, however, in marine mammals, the role of the tear film in protection of the ocular surface is not known. In an effort to better understand the function of tears in maintaining health of the marine mammal eye surface, we examined ocular glands of the California sea lion, and began to characterize the biochemical nature of the tear film of pinnipeds. Procedures Glands dissected from California sea lion eyelids and adnexa were examined for gross morphology, sectioned for microscopic analysis, and stained with haematoxylin and eosin. The tear film was examined using interferometry. Tears were collected from humans and pinnipeds for analysis of protein and carbohydrate content. Results The sea lion has sebaceous glands in the lid, but these glands are different in size and orientation compared to typical meibomian glands of terrestrial mammals. Two other accessory ocular glands located dorsotemporally and medially appeared to be identical in morphology, with tubulo-acinar morphology. An outer lipid layer on the ocular surface of the sea lion was not detected using interferometry, consistent with the absence of typical meibomian glands. Similar to human tears, the tears of pinnipeds contain several proteins but the ratio of carbohydrate to protein was greater than that in human tears. Conclusions Our findings indicate that the ocular gland architecture and biochemical nature of the tear film of pinnipeds have evolved to adapt to the challenges of an aquatic environment. PMID:23067374

  10. Assessment of tear secretions in healthy Indian volunteers.

    PubMed

    Mishra, Panna; Srivastava, Divya; Rajesh Misra; Malik, V K; Trivedi, Vikas

    2014-01-01

    Dry eye syndrome is currently seen with increasing frequency throughout the world including India. An evaluation of tear physiology in the form of tear secretion and tear film stability is the most important aspect of dry eye diagnosis. The aim of this study is to investigate the age and gender related changes in the result of these tear function tests (Schirmers Test and Tear Break up time) in normal Indian population. This cross- sectional observational study included 120 normal subjects (60 Male and 60 females) with no ocular symptoms or ocular surface disorders. Schirmer and tear film break-up time tests were assessed in both eyes of each subject. The study subjects were divided into 4 groups according to their ages (<20 y, 20-40 y, 41-60 y and >60 y) each group was composed of 60 eyes of 30 subjects (15 male and 15 female subjects). The One way ANOVA test and the Statagraphic software was used for statistical analysis. We detected a statistically significant decline in both the tear function tests with increasing age. Tear function tests did not show statistically significant difference according to sex. This study suggests that the age of subjects should be taken into consideration in the evaluation of tear function test results. It is also revealed that Indian population values are different from Caucasian and Chinese values. We propose age specific cut off values of tear function tests in Indian population to aid in the diagnosis of dry eye in Indian conditions.

  11. Biological Augmentation of Rotator Cuff Tendon Repair

    PubMed Central

    Kovacevic, David

    2008-01-01

    A histologically normal insertion site does not regenerate following rotator cuff tendon-to-bone repair, which is likely due to abnormal or insufficient gene expression and/or cell differentiation at the repair site. Techniques to manipulate the biologic events following tendon repair may improve healing. We used a sheep infraspinatus repair model to evaluate the effect of osteoinductive growth factors and BMP-12 on tendon-to-bone healing. Magnetic resonance imaging and histology showed increased formation of new bone and fibrocartilage at the healing tendon attachment site in the treated animals, and biomechanical testing showed improved load-to-failure. Other techniques with potential to augment repair site biology include use of platelets isolated from autologous blood to deliver growth factors to a tendon repair site. Modalities that improve local vascularity, such as pulsed ultrasound, have the potential to augment rotator cuff healing. Important information about the biology of tendon healing can also be gained from studies of substances that inhibit healing, such as nicotine and antiinflammatory medications. Future approaches may include the use of stem cells and transcription factors to induce formation of the native tendon-bone insertion site after rotator cuff repair surgery. PMID:18264850

  12. Percutaneous techniques for tendon transfers in the foot and ankle.

    PubMed

    Panchbhavi, Vinod Kumar

    2014-03-01

    Tendon transfer procedures are useful for replacing a dysfunctional or diseased tendon or for restoring muscle imbalance. The tendon to be transferred is harvested as distal as is necessary to provide adequate length for rerouting and attachment at the different site. The harvesting of tendon itself can be attained using an open surgical approach or minimally invasive percutaneous techniques that limit surgical exposure. This article describes percutaneous techniques for tendon transfer procedures used to address foot and ankle disorders.

  13. Exercise following a short immobilization period is detrimental to tendon properties and joint mechanics in a rat rotator cuff injury model.

    PubMed

    Peltz, Cathryn D; Sarver, Joseph J; Dourte, Leann M; Würgler-Hauri, Carola C; Williams, Gerald R; Soslowsky, Louis J

    2010-07-01

    Rotator cuff tears are a common clinical problem that can result in pain and disability. Previous studies in a rat model showed enhanced tendon to bone healing with postoperative immobilization. The objective of this study was to determine the effect of postimmobilization activity level on insertion site properties and joint mechanics in a rat model. Our hypothesis was that exercise following a short period of immobilization will cause detrimental changes in insertion site properties compared to cage activity following the same period of immobilization, but that passive shoulder mechanics will not be affected. We detached and repaired the supraspinatus tendon of 22 Sprague-Dawley rats, and the injured shoulder was immobilized postoperatively for 2 weeks. Following immobilization, rats were prescribed cage activity or exercise for 12 weeks. Passive shoulder mechanics were determined, and following euthanasia, tendon cross-sectional area and mechanical properties were measured. Exercise following immobilization resulted in significant decreases compared to cage activity in range of motion, tendon stiffness, modulus, percent relaxation, and several parameters from both a structurally based elastic model and a quasi-linear viscoelastic model. Therefore, we conclude that after a short period of immobilization, increased activity is detrimental to both tendon mechanical properties and shoulder joint mechanics, presumably due to increased scar production.

  14. Tendon injury and tendinopathy: healing and repair.

    PubMed

    Sharma, Pankaj; Maffulli, Nicola

    2005-01-01

    Tendon disorders are frequent and are responsible for substantial morbidity both in sports and in the workplace. Tendinopathy, as opposed to tendinitis or tendinosis, is the best generic descriptive term for the clinical conditions in and around tendons arising from overuse. Tendinopathy is a difficult problem requiring lengthy management, and patients often respond poorly to treatment. Preexisting degeneration has been implicated as a risk factor for acute tendon rupture. Several physical modalities have been developed to treat tendinopathy. There is limited and mixed high-level evidence to support the, albeit common, clinical use of these modalities. Further research and scientific evaluation are required before biological solutions become realistic options.

  15. Fibromatosis of the flexor pollicus longus tendon

    PubMed Central

    Damkat-Thomas, L; Black, CE; Herbert, K

    2010-01-01

    An unusual case of fibromatosis of the dominant left flexor pollicus longus (FPL) in a thirteen year old schoolboy. Initially presenting with pain in the thenar eminence and difficulty flexing the metacarpal phalangeal joint (MPJ), other symptoms include locking, triggering and difficulty writing. MRI showed a 4cm segment of thickened abnormal tendon. Intra-operatively three 1cm nodules were excised from the FPL while preserving the tendon. Histopathology reported the nodules as fibromatosis. A literature search revealed that this has not previously been reported although symptomatic tendon sheath fibromas have. Our patient achieved a good result following surgical intervention and the two year review has shown no complications. PMID:24946359

  16. A review of work on artificial tendons.

    PubMed

    Murray, G A; Semple, J C

    1979-07-01

    Work done to date on artificial tendons by many authors is described in chronological order. A brief description of the techniques and materials is given in each case, with a summary of the results. The overall implications of the work are discussed in terms of prosthesis durability, the attachment to bone and tendon, mechanical properties and the volume of scar tissue generated. It is concluded that construction of a permanent artificial tendon is a realistic and worthwhile aim; further experimental work ought to include long term in vivo testing with means provided for monitoring any drift of the attachment points.

  17. 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

  18. Ultrasonic stress measurements in prestressing tendons

    NASA Astrophysics Data System (ADS)

    Washer, Glenn A.; Green, Robert E.

    2002-05-01

    The goal of this research was to examine ultrasonic stress measurement techniques for the condition assessment of prestressing tendons. Acoustoelastic measurements were made in prestressing rods and strands, and constants are reported that relate the change in ultrasonic velocity to the change in stress. The effects of dispersion in prestressing tendons, which act as circular wave guides for ultrasonic waves, were measured and evaluated. For this research, narrow-band, noncontact Electromagnetic Acoustic Transducers (EMATs) were designed to launch and receive ultrasonic waves propagating within the tendons.

  19. Les plaies du tendon patellaire

    PubMed Central

    Mechchat, Atif; Elidrissi, Mohammed; Mardy, Abdelhak; Elayoubi, Abdelghni; Shimi, Mohammed; Elibrahimi, Abdelhalim; Elmrini, Abdelmajid

    2014-01-01

    Les plaies du tendon patellaire sont peu fréquentes et sont peu rapportés dans la littérature, contrairement aux ruptures sous cutanées. Les sections du tendon patellaire nécessitent une réparation immédiate afin de rétablir l'appareil extenseur et de permettre une récupération fonctionnelle précoce. A travers ce travail rétrospectif sur 13 cas, nous analysons les aspects épidémiologiques, thérapeutiques et pronostiques de ce type de pathologie en comparant différents scores. L’âge moyen est de 25 ans avec une prédominance masculine. Les étiologies sont dominées par les accidents de la voie publique (68%) et les agressions par agent tranchant (26%) et contendant (6 %). Tous nos patients ont bénéficié d'un parage chirurgical avec suture tendineuse direct protégée par un laçage au fils d'aciers en légère flexion. La rééducation est débutée après sédation des phénomènes inflammatoires. Au dernier recul les résultats sont excellents et bon à 92%. Nous n'avons pas noté de différence de force musculaire et d'amplitude articulaire entre le genou sain et le genou lésé. Les lésions ouvertes du tendon patellaire est relativement rare. La prise en charge chirurgicale rapide donne des résultats assez satisfaisants. La réparation est généralement renforcée par un semi-tendineux, synthétique ou métallique en forme de cadre de renfort pour faciliter la réadaptation et réduire le risque de récidive après la fin de l'immobilisation. PMID:25170379

  20. Changes in the Chemical Barrier Composition of Tears in Alzheimer's Disease Reveal Potential Tear Diagnostic Biomarkers.

    PubMed

    Kalló, Gergő; Emri, Miklós; Varga, Zsófia; Ujhelyi, Bernadett; Tőzsér, József; Csutak, Adrienne; Csősz, Éva

    2016-01-01

    Alzheimer's disease (AD) is one of the most common neurodegenerative diseases, with increasing prevalence affecting millions of people worldwide. Currently, only autopsy is able to confirm the diagnosis with a 100% certainty, therefore, biomarkers from body fluids obtained by non-invasive means provide an attractive alternative for the diagnosis of Alzheimer`s disease. Global changes of the protein profile were examined by quantitative proteomics; firstly, electrophoresis and LC-MS/MS were used, thereafter, SRM-based targeted proteomics method was developed and applied to examine quantitative changes of tear proteins. Alterations in the tear flow rate, total tear protein concentration and composition of the chemical barrier specific to AD were demonstrated, and the combination of lipocalin-1, dermcidin, lysozyme-C and lacritin was shown to be a potential biomarker, with an 81% sensitivity and 77% specificity.

  1. 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.

  2. 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.

  3. Traumatic tibialis anterior tendon rupture: treatment with a two-stage silicone tube and an interposition hamstring tendons graft protocol.

    PubMed

    Kontogeorgakos, Vasileios; Koutalos, Antonios; Hantes, Michael; Manoudis, Gregory; Badras, Leonidas; Malizos, Konstantinos

    2015-03-01

    A novel technique for managing ruptured tibialis anterior tendon complicated by infection and tendon substance loss in a young adult is described. A two-stage reconstruction technique with a silicon tube and tendon autograft was performed. At first, after local control of the infection, scar excision and placement of a silicone tube was performed. Ten weeks later, ipsilateral hamstrings tendons were harvested and bridged the 7 cm tendon gap. Eighteen months later, the patient has excellent clinical and functional outcome.

  4. Osseous Injury Associated With Ligamentous Tear of the Knee.

    PubMed

    Lee, Chee Hwee; Tan, Chih Feng; Kim, Okwha; Suh, Kyung Jin; Yao, Min-Szu; Chan, Wing P; Wu, Jim S

    2016-11-01

    One of the most common knee injuries is ligament tear, which may initially manifest as an osseous injury in radiographs. Radiologists should therefore be able to recognize ligament tears of the knee as osseous abnormalities in images. This review focuses on the imaging features of knee ligament injuries and their related osseous injuries: anterior cruciate ligament (ACL) tear with Segond fracture; associated marrow contusion; ACL avulsion fracture; posterior cruciate ligament (PCL) tear with osseous avulsion of the ligament including arcuate sign; reverse Segond fracture; PCL avulsion fracture; medial collateral ligament tear with Pellegrini-Stieda disease; lateral collateral ligament tear with avulsion fracture of the fibular head; and patellar ligament injuries with Osgood-Schlatter and Sinding-Larsen-Johansson.

  5. Management of irreparable rotator cuff tears and glenohumeral arthritis.

    PubMed

    Laudicina, Laurence; D'Ambrosia, Robert

    2005-04-01

    Glenohumeral arthritis with irreparable rotator cuff tears remain a difficult entity to treat. Varied causes include rotator cuff tear arthropathy, osteoarthritis, or rheumatoid arthritis with irreparable cuff tear. Common symptoms are progressive pain and dysfunction. Physical examination may reveal pain, crepitance, rotator cuff weakness, and loss of motion and function. Radiographs may reveal varying degrees of osteophyte formation, sclerotic bone, superior humeral head migration, and bony erosion. Additional imaging modalities may reveal cuff tear size, retraction, atrophy, and fatty infiltration. Failure of nonoperative management may lead to operative intervention. Rotator cuff repair or reconstruction may help prevent progression of tears and future arthritic changes. In patients with moderate to severe glenohumeral arthritis and irreparable rotator cuff tears, hemiarthroplasty is currently the procedure of choice. For patients with severe cuff dysfunction or loss of coracoacromial arch, or for patients who require revision, the reverse shoulder prosthesis may offer a treatment option. Future management continues to be defined with additional study.

  6. 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.

  7. Jumper's Knee (Patellar Tendonitis) (For Parents)

    MedlinePlus

    ... Looking for Health Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development ( ... area of the body). Constant jumping, landing, and changing direction can cause strains, tears, and damage to ...

  8. Idiopathic horseshoe-like macular tear: a case report

    PubMed Central

    Kubota, Masaomi; Shibata, Tomohiro; Gunji, Hisato; Tsuneoka, Hiroshi

    2016-01-01

    Background Although a few cases with idiopathic horseshoe-like macular tear have been reported, the mechanism remains unknown and a standard treatment has yet to be determined. Objective To report the outcome for a patient with idiopathic horseshoe-like macular tear who underwent vitreous surgery. Case report A 65-year-old man with no previous injury or ophthalmic disease presented with abnormal vision in his left eye. Best-corrected visual acuity was 0.8 in the right and 0.3 in the left, and the relative afferent pupillary defect was negative. Ophthalmoscopy revealed a horseshoe-like tear on the temporal side of the macula in the left eye. The tear size was 0.75 disc diameters (DD). Optical coherence tomography showed that the focal retinal detachment reached the fovea. A few days after the first visit, there was no longer adhesion of the flap of the tear to the retina and the tear size had increased to 1.5 DD. The patient underwent vitreous surgery similar to large macular hole surgery, with the tear closure repaired using the inverted internal limiting membrane flap technique with 20% SF6 gas tamponade. Although the tear decreased to 0.5 DD after the surgery, complete closure of the tear was not achieved. Conclusion While cases with horseshoe-like macular tear following trauma and branch retinal vein occlusion have been reported, to the best of our knowledge, this is the first reported idiopathic case. In the present case, there was expansion of the tear until the patient actually underwent surgery. If vertical vitreous traction indeed plays a role in horseshoe-like macular tears, this will need to be taken into consideration at the time of the vitreous surgery in these types of cases. PMID:27555798

  9. Development of high shrinkage polyethylene terephthalate (PET) shape memory polymer tendons for concrete crack closure

    NASA Astrophysics Data System (ADS)

    Teall, Oliver; Pilegis, Martins; Sweeney, John; Gough, Tim; Thompson, Glen; Jefferson, Anthony; Lark, Robert; Gardner, Diane

    2017-04-01

    The shrinkage force exerted by restrained shape memory polymers (SMPs) can potentially be used to close cracks in structural concrete. This paper describes the physical processing and experimental work undertaken to develop high shrinkage die-drawn polyethylene terephthalate (PET) SMP tendons for use within a crack closure system. The extrusion and die-drawing procedure used to manufacture a series of PET tendon samples is described. The results from a set of restrained shrinkage tests, undertaken at differing activation temperatures, are also presented along with the mechanical properties of the most promising samples. The stress developed within the tendons is found to be related to the activation temperature, the cross-sectional area and to the draw rate used during manufacture. Comparisons with commercially-available PET strip samples used in previous research are made, demonstrating an increase in restrained shrinkage stress by a factor of two for manufactured PET filament samples.

  10. The "dark tendon sign" (DTS): a sonographic indicator for idiopathic trigger finger.

    PubMed

    Gruber, Hannes; Peer, Siegfried; Loizides, Alexander

    2011-05-01

    Although the diagnosis of "idiopathic trigger finger" (stenosing tenovaginitis) is normally based on clinical examination alone, to date there is no reliable evaluation defining this idiopathic disease beyond an exclusion of secondary causes or an unnecessary sonographic certification of high-grade impairment. By standardized assessment of 32 patients who retrospectively fulfilled the study inclusion criteria and their comparison to a matched group of volunteers, we defined the diagnostic efficiency of the here newly proposed sonographic dark tendon sign (DTS) alone, of impaired tendon gliding alone and the combination of these two features. Pulley thickness in patients and volunteers was significantly different. The combination of clinically impaired tendon gliding plus the DTS reached a sensitivity and diagnostic efficiency of 100%. We propose this diagnostic combination as the new first line assessment features for the quick definition of idiopathic stenosing tendovaginitis during daily routine

  11. Fiber Bragg grating displacement sensor for movement measurement of tendons and ligaments.

    PubMed

    Ren, Liang; Song, Gangbing; Conditt, Michael; Noble, Philip C; Li, Hongnan

    2007-10-01

    Biomechanical studies often involve measurements of the strains developed in tendons or ligaments in posture or locomotion. Fiber-optic sensors present an attractive option for the measurement of strains in tendons and ligaments because of their low cost, ease of implementation, and increased accuracy compared with other implantable transducers. A new displacement sensor based on a fiber Bragg grating and shape memory alloy technology is proposed for the monitoring of tendon and ligament strains in different postures and in locomotion. After sensor calibration in the laboratory, a comparison of the fiber sensors and traditional camera displacement sensors was carried out to evaluate the performance of the fiber sensor during the application of tension to the Achilles tendon. Additional experiments were performed in cadaver knees to assess the suitability of these fiber sensors to measure ligament deformation in a variety of simulated postures. The results demonstrate that the proposed fiber Bragg grating sensor is a highly accurate, easily implantable, and minimally invasive method of measuring tendon and ligament displacement.

  12. Position Control of Tendon-Driven Fingers

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  13. Flexor tendon repair in zone III.

    PubMed

    Al-Qattan, Mohammad M

    2011-01-01

    There is a paucity of the literature on the outcome of zone III flexor tendon injuries. In this paper, we report on the results of zone III flexor tendon repair in 35 consecutive adult patients with clean cut lacerations of both flexor tendons in 42 fingers. There were 25 men and 10 women with an average age of 32 years. Repair of both flexor tendons was performed using 'figure of eight' core sutures and a continuous epitendinous suture. Postoperatively, an immediate active range of motion protocol was applied to ensure full active extension of the interphalangeal joints. The results were assessed using the Strickland-Glogovac grading system. There were no ruptures. One patient with two injured fingers developed complex regional pain syndrome and the final outcome was fair in both fingers. In the remaining 34 patients (40 fingers), 33 patients (38 fingers) had an excellent outcome and the remaining patient (two fingers) had a good outcome.

  14. Glycosaminoglycans in Tendon Physiology, Pathophysiology, and Therapy.

    PubMed

    Ryan, Christina N M; Sorushanova, Anna; Lomas, Alex J; Mullen, Anne Maria; Pandit, Abhay; Zeugolis, Dimitrios I

    2015-07-15

    Although glycosaminoglycans constitute a minor portion of native tissues, they play a crucial role in various physiological processes, while their abnormal expression is associated with numerous pathophysiologies. Glycosaminoglycans have become increasingly prevalent in biomaterial design for tendon repair, given their low immunogenicity and their inherent capacity to stimulate the regenerative processes, while maintaining resident cell phenotype and function. Further, their incorporation into three-dimensional scaffold conformations significantly improves their mechanical properties, while reducing the formation of peritendinous adhesions. Herein, we discuss the role of glycosaminoglycans in tendon physiology and pathophysiology and the advancements achieved to date using glycosaminoglycan-functionalized scaffolds for tendon repair and regeneration. It is evidenced that glycosaminoglycan functionalization has led to many improvements in tendon tissue engineering and it is anticipated to play a pivotal role in future reparative therapies.

  15. Assessment and treatment strategies for rotator cuff tears

    PubMed Central

    Al-Hakim, Wisam; Noorani, Ali

    2014-01-01

    Tears of the rotator cuff are common and becoming an increasingly frequent problem. There is a vast amount of literature on the merits and limitations of the various methods of clinical and radiological assessment of rotator cuff tears. This is also the case with regard to treatment strategies. Certain popular beliefs and principles practiced widely and the basis upon which they are derived may be prone to inaccuracy. We provide an overview of the historical management of rotator cuff tears, as well as an explanation for how and why rotator cuff tears should be managed, and propose a structured methodology for their assessment and treatment. PMID:27582960

  16. Effects of smoking on tear film and ocular surface.

    PubMed

    Yoon, Kyung-Chul; Song, Byoung-Yong; Seo, Man-Seong

    2005-03-01

    This study was performed to evaluate the changes of tear film and ocular surface caused by smoking. Symptom scoring, tear film break-up time (BUT), basal tear secretion test, corneal sensitivity test, keratoepitheliopathy scoring, and conjunctival impression cytology were performed in 29 smokers (58 eyes) and 26 non-smokers (52 eyes). Tear film BUT, basal tear secretion, corneal sensitivity, and squamous metaplasia were 7.71+/-2.66 sec, 6.29+/-2.85 mm, 53.69+/-5.69 mm, and 2.45+/-1.26 in smokers and 9.62+/-3.14 sec, 10.04+/-3.87 mm, 56.46+/-4.79 mm, and 1.12+/-0.83 in non-smokers, respectively (p<0.05). Symptom score, keratoepitheliopathy score, and goblet cell density were not significantly different between the two groups. Tear film BUT was shorter, basal tear secretion and corneal sensitivity were lower, and squamous metaplasia was higher in heavy smokers than in light smokers. In conclusion, smoking deteriorates the tear film and ocular surface with decreased quantity and quality of tear film, decreased corneal sensitivity, and squamous metaplasia, and this deterioration is related to the amount of smoking.

  17. Integrated multimodal metrology for objective and noninvasive tear evaluation.

    PubMed

    Kottaiyan, Ranjini; Yoon, Geunyoung; Wang, Qi; Yadav, Rahul; Zavislan, James M; Aquavella, James V

    2012-01-01

    The clinical tests used to assess tear film and diagnose dry eye are invasive and produce results that are different from natural tear characteristics. There is a need to objectively and noninvasively assess tear parameters under controlled environmental circumstances to refine dry eye diagnosis and therapy. We have developed multimodal tear imaging systems integrated in a chamber in which individual environmental factors can be precisely varied to investigate their impacts on tear parameters. With the custom-built high-resolution wavefront sensor combined with placido disc, it is possible to objectively detect two-dimensional tear breakups in real time and evaluate its impact on visual quality. Micrometer ultra-high resolution optical coherence tomography (OCT) enables us to quantify thickness and volume of the tear over the cornea and tear menisci. The ocular surface imaging ellipsometer uses polarized illumination from which both the lipid refractive index and thickness can be measured at a very high resolution. Using an enhanced thermal camera, we measure the ocular surface temperature noninvasively, which makes it possible to study spatial and temporal changes in tear evaporation. The multimodal deployment of these four components in the controlled chamber will assist in better differentiating the various clinical dry eye entities and will lead to the development of specific dry eye treatments.

  18. Lipoma arborescens of the biceps tendon sheath.

    PubMed

    White, Eric A; Omid, Reza; Matcuk, George R; Domzalski, Jerome T; Fedenko, Alexander N; Gottsegen, Christopher J; Forrester, Deborah M; Patel, Dakshesh B

    2013-10-01

    Lipoma arborescens, described as lipomatous infiltration and distention of synovial villi resulting in a frond-like appearance, most frequently affects the suprapatellar recess of the knee. While there have been reports of this entity involving the upper extremity joints, bursa, and tendon sheaths, we present the first reported case of lipoma arborescens isolated to the biceps tendon sheath. We describe imaging and histologic findings with clinical correlation.

  19. Mechanical properties of human patellar tendon at the hierarchical levels of tendon and fibril.

    PubMed

    Svensson, René B; Hansen, Philip; Hassenkam, Tue; Haraldsson, Bjarki T; Aagaard, Per; Kovanen, Vuokko; Krogsgaard, Michael; Kjaer, Michael; Magnusson, S Peter

    2012-02-01

    Tendons are strong hierarchical structures, but how tensile forces are transmitted between different levels remains incompletely understood. Collagen fibrils are thought to be primary determinants of whole tendon properties, and therefore we hypothesized that the whole human patellar tendon and its distinct collagen fibrils would display similar mechanical properties. Human patellar tendons (n = 5) were mechanically tested in vivo by ultrasonography. Biopsies were obtained from each tendon, and individual collagen fibrils were dissected and tested mechanically by atomic force microscopy. The Young's modulus was 2.0 ± 0.5 GPa, and the toe region reached 3.3 ± 1.9% strain in whole patellar tendons. Based on dry cross-sectional area, the Young's modulus of isolated collagen fibrils was 2.8 ± 0.3 GPa, and the toe region reached 0.86 ± 0.08% strain. The measured fibril modulus was insufficient to account for the modulus of the tendon in vivo when fibril content in the tendon was accounted for. Thus, our original hypothesis was not supported, although the in vitro fibril modulus corresponded well with reported in vitro tendon values. This correspondence together with the fibril modulus not being greater than that of tendon supports that fibrillar rather than interfibrillar properties govern the subfailure tendon response, making the fibrillar level a meaningful target of intervention. The lower modulus found in vitro suggests a possible adverse effect of removing the tissue from its natural environment. In addition to the primary work comparing the two hierarchical levels, we also verified the existence of viscoelastic behavior in isolated human collagen fibrils.

  20. Grasp Assist Device with Shared Tendon Actuator Assembly

    NASA Technical Reports Server (NTRS)

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

    2015-01-01

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

  1. Tension Distribution in a Tendon-Driven Robotic Finger

    NASA Technical Reports Server (NTRS)

    Abdallah, Muhammad E. (Inventor); Platt, Robert (Inventor); Wampler, II, Charles W. (Inventor)

    2013-01-01

    A method is provided for distributing tension among tendons of a tendon-driven finger in a robotic system, wherein the finger characterized by n degrees of freedom and n+1 tendons. The method includes determining a maximum functional tension and a minimum functional tension of each tendon of the finger, and then using a controller to distribute tension among the tendons, such that each tendon is assigned a tension value less than the maximum functional tension and greater than or equal to the minimum functional tension. The method satisfies the minimum functional tension while minimizing the internal tension in the robotic system, and satisfies the maximum functional tension without introducing a coupled disturbance to the joint torques. A robotic system includes a robot having at least one tendon-driven finger characterized by n degrees of freedom and n+1 tendons, and a controller having an algorithm for controlling the tendons as set forth above.

  2. Laminar Tendon Composites with Enhanced Mechanical Properties

    PubMed Central

    Alberti, Kyle A.; Sun, Jeong-Yun; Illeperuma, Widusha R.; Suo, Zhigang; Xu, Qiaobing

    2015-01-01

    Purpose A strong isotropic material that is both biocompatible and biodegradable is desired for many biomedical applications, including rotator cuff repair, tendon and ligament repair, vascular grafting, among others. Recently, we developed a technique, called “bioskiving” to create novel 2D and 3D constructs from decellularized tendon, using a combination of mechanical sectioning, and layered stacking and rolling. The unidirectionally aligned collagen nanofibers (derived from sections of decellularized tendon) offer good mechanical properties to the constructs compared with those fabricated from reconstituted collagen. Methods In this paper, we studied the effect that several variables have on the mechanical properties of structures fabricated from tendon slices, including crosslinking density and the orientation in which the fibers are stacked. Results We observed that following stacking and crosslinking, the strength of the constructs is significantly improved, with crosslinked sections having an ultimate tens ile strength over 20 times greater than non-crosslinked samples, and a modulus nearly 50 times higher. The mechanism of the mechanical failure mode of the tendon constructs with or without crosslinking was also investigated. Conclusions The strength and fiber organization, combined with the ability to introduce transversely isotropic mechanical properties makes the laminar tendon composites a biocompatiable material that may find future use in a number of biomedical and tissue engineering applications. PMID:25691802

  3. The cell biology of suturing tendons

    PubMed Central

    Wong, J.K.F.; Alyouha, S.; Kadler, K.E.; Ferguson, M.W.J.; McGrouther, D.A.

    2010-01-01

    Trauma by suturing tendon form areas devoid of cells termed “acellular zones” in the matrix. This study aimed to characterise the cellular insult of suturing and acellular zone formation in mouse tendon. Acellular zone formation was evaluated using single grasping sutures placed using flexor tendons with time lapse cell viability imaging for a period of 12 h. Both tension and injury were required to induce cell death and cell movement in the formation of the acellular zone. DNA fragmentation studies and transmission electron microscopy indicated that cells necrosed. Parallel in vivo studies showed that cell-to-cell contacts were disrupted following grasping by the suture in tensioned tendon. Without tension, cell death was lessened and cell-to-cell contacts remained intact. Quantitative immunohistochemistry and 3D cellular profile mapping of wound healing markers over a one year time course showed that acellular zones arise rapidly and showed no evidence of healing whilst the wound healing response occurred in the surrounding tissues. The acellular zones were also evident in a standard modified “Kessler” clinical repair. In conclusion, the suture repair of injured tendons produces acellular zones, which may potentially cause early tendon failure. PMID:20600895

  4. 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.

  5. DISSEMINATED REFRACTARY TUBERCULOSIS WITH BICEPS TENDON INVOLVEMENT IN AN IMMUNOCOMPETENT PATIENT

    PubMed Central

    dos Reis Oliveira, Marcelo; Schiefer, Márcio; da Silva, Marcos Britto; Fontenelle, César; Júnior, Yonder Archanjo Ching-San; Franco, José Sérgio

    2015-01-01

    Objective: The authors report a rare case of disseminated tuberculosis which had compromised the long head of biceps tendon and shoulder joint, during standard drug therapy. Methods: On a first sight, the accurate diagnosis wasn't accomplished and the patient had been treated with physiotherapy for rotator cuff tear. However, the patient presented with a fast growing mass in anterior region of the proximal third of the arm, complaining of pain increase. Aspirative punction of the mass revealed a yellow fluid and the laboratorial analysis confirmed infection by M. Tuberculosis. The patient was treated with surgical debridement and his drug therapy was changed. Results: Resolution of infectious status and complete shoulder function restoration was succeeded. Conclusion: Due to its high prevalence in Brazil, tuberculosis must always be considered as a possible cause of inflammatory joint disease, even in immunocompetent patients. PMID:27004180

  6. Assessment of Tear Film Quality among Smokers Using Tear Ferning Patterns

    PubMed Central

    Al-Shehri, Adil; Alanazi, Saud A.; Abusharaha, Ali; Fagehi, Raied

    2016-01-01

    Purpose. To investigate the effect of cigarette smoking on the ocular tear film. Methods. Thirty healthy young male cigarette smokers (20–38 years old) and 30 healthy age matched nonsmokers were enrolled in the study. McMonnies questionnaire, slit lamp, and PRT test were used to screen the subjects. Tear samples were collected from the right eyes and tear ferning patterns were observed and graded. Results. The mean MacMonnies scores and TF grades were significantly higher in the smoker subjects (mean ± SD = 9.83 ± 5.22 and 0.96 ± 0.54, resp.) compared to nonsmokers (mean ± SD = 5.96 ± 3.06 and 0.41 ± 0.38, resp.). The mean values obtained from PRT and TBUT tests were 22.23 ± 6.35 mm and 12.17 ± 3.81 s for smokers and 22.16 ± 5.63 mm and 14.13 ± 2.62 s for nonsmokers, respectively. Strong correlations were found between MacMonnies scores and both PRT (r = 0.596) and TF (r = 0.516). There was statistically significant difference in TF grades (p = 0.00), TBUT (p = 0.036) and McMonnies (p = 0.02) between smokers and nonsmokers. Conclusion. Cigarette smoking could have a significant effect on the tear film quality of the eye. PMID:28003910

  7. A Prospective Comparative Study of High Resolution Ultrasound and MRI in the Diagnosis of Rotator Cuff Tears in a Tertiary Hospital of North India

    PubMed Central

    Chauhan, Narvir Singh; Ahluwalia, Ajay; Sharma, Yash Paul; Thakur, Lokesh

    2016-01-01

    Summary Background To evaluate the accuracy of high resolution ultrasound (USG) and MRI in the diagnosis of rotator cuff tears (RCT) and to determine if high resolution USG compares favorably in sensitivity and specificity to MRI in the diagnosis of rotator cuff injury. Material/Methods In this prospective comparative study, 40 patients with clinically suspected rotator cuff tears underwent both ultrasound and MRI of the shoulder. Out of these 40 patients, 31 patients who had positive findings for rotator cuff tears on ultrasound and/or MRI were finally included in the study while the remaining 9 patients with negative or unrelated findings were excluded. The USG and MRI were interpreted by two radiologists experienced in musculoskeletal radiology and blinded to findings of each other. Comparison was done using MRI as a standard reference. Results The agreement between USG and MRI for diagnosis of RCTs was statistically excellent; USG showed a sensitivity of 86.7% and a specificity of 100% for full-thickness tears, and a sensitivity of 89.7% and a specificity of 98.8% for partial-thickness tears; observed accuracy for full thickness tears was 98.4% and 95.9% for partial thickness tears. The Kappa coefficient of association was 0.91 for full thickness tears and 0.90 for partial thickness tears. Conclusions Considering the comparable diagnostic accuracy of USG and MRI, the former modality can be used as a first-line investigation for diagnosis of RCT. MRI should be used secondarily as a problem-solving tool either following an equivocal shoulder USG or for delineation of anatomy in cases where surgical correction is needed. PMID:27800039

  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. Neurostimulation of the Lacrimal Nerve for Enhanced Tear Production

    PubMed Central

    Kossler, Andrea L.; Wang, Jianhua; Feuer, William; Tse, David T.

    2014-01-01

    Purpose To design a proof-of-concept study to assess the effect of lacrimal nerve stimulation (LNS) with an implantable pulse generator (IPG) to increase aqueous tear production. Methods Experimental animal study design of six Dutch Belted rabbits. Ultra high-resolution optical coherence tomography (UHR-OCT) quantified tear production by measuring the baseline tear volume of each rabbit’s right and left eye. A neurostimulator was implanted adjacent to the right lacrimal nerve. After two minutes of LNS (100 μs, 1.6 mAmp, 20 Hz, 5–8 volts), the tear volumes were measured with UHR-OCT. The change in tear volume was quantified and compared to the non-stimulated left eye. Three rabbits underwent chronic LNS (100 μS, 1.6 mAmp, 10 Hz, 2 volts) and their lacrimal glands were harvested for histopathologic analysis. Results UHR-OCT imaging of the right eyes tear volume showed a 441% average increase in tear production after LNS as a percent of baseline. After stimulation, right eyes had statistically significant greater increase in tear volumes than left eyes (p=0.028, Wilcoxon test). Post-stimulation right eye tear volumes were significantly greater compared to baseline (p=0.028, Wilcoxon test). Histopathologic examination of the lacrimal glands showed no discernible tissue damage from chronic neurostimulation. Additionally, there were no gross adverse effects on the general well-beings of the animals due to chronic stimulation. Conclusions Lacrimal nerve stimulation with an implantable pulse generator appears to increase aqueous tear production. Chronic LNS showed no histopathologic lacrimal gland damage. This study suggests LNS is a promising new treatment strategy to increase aqueous tear production. PMID:25126767

  10. 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.

  11. Acute partial rupture of the common extensor tendon.

    PubMed

    Kachrimanis, G; Papadopoulou, O

    2010-06-01

    Rupture of the common extensor tendon is the most common acute tendon injury of the elbow. The authors describe a case of a patient with a clinical history of tendinopathy caused by functional overload of the common extensor tendon, treated also with infiltrations of steroids, and subsequent partial rupture of the tendon during sport activity. The diagnosis was made clinically and at ultrasound (US) examination; US follow-up after some time showed the healing of the lesion. This case confirms that injections of steroids may be a contributory cause of tendon rupture, and emphasizes the sensitivity and specificity of US in the study of pathologies of the elbow tendons.

  12. Bi-fluid and neoclassical effect on a Double-Tearing mode in Tore Supra

    SciTech Connect

    Maget, Patrick Garbet, Xavier; Février, Olivier; Ségui, Jean-Luc; Lütjens, Hinrich; Luciani, Jean-François

    2014-06-15

    Tearing modes associated to hollow current profiles are prone to grow in moderate performance plasmas and often constrain the realization of non-inductive discharges in the Tore Supra tokamak, where long pulse duration is performed using Lower Hybrid waves for providing most of the plasma current. The prediction of MHD boundaries in such scenarios is complicated by the importance of diamagnetic effects, combined with curvature stabilization, which determine the stability of these modes. We show that diamagnetic effects, as well as neoclassical forces, are playing a key role in the linear and nonlinear regimes of Double-Tearing Modes on q = 5/3 and q = 2 in these experimental conditions. Detailed comparison with experimental measurements, combined with a scaling in plasma resistivity, give constraints about the experimental equilibrium. Resistive-Interchange Modes destabilized by diamagnetic rotation could also play a role in degrading the energy confinement in the negative magnetic shear region.

  13. A Comparison of Two Injection Locations in Obese Patients Having Lower Leg/Foot Surgery

    ClinicalTrials.gov

    2015-10-13

    Strain of Muscle and/or Tendon of Lower Leg; Fracture of Lower Leg; Crushing Injury of Lower Leg; Fracture Malunion - Ankle and/ or Foot; Complete Tear, Ankle and/or Foot Ligament; Pathological Fracture - Ankle and/or Foot; Loose Body in Joint of Ankle and/or Foot

  14. Novel Model of Tendon Regeneration Reveals Distinct Cell Mechanisms Underlying Regenerative and Fibrotic Tendon Healing

    PubMed Central

    Howell, Kristen; Chien, Chun; Bell, Rebecca; Laudier, Damien; Tufa, Sara F.; Keene, Douglas R.; Andarawis-Puri, Nelly; Huang, Alice H.

    2017-01-01

    To date, the cell and molecular mechanisms regulating tendon healing are poorly understood. Here, we establish a novel model of tendon regeneration using neonatal mice and show that neonates heal via formation of a ‘neo-tendon’ that differentiates along the tendon specific lineage with functional restoration of gait and mechanical properties. In contrast, adults heal via fibrovascular scar, aberrant differentiation toward cartilage and bone, with persistently impaired function. Lineage tracing identified intrinsic recruitment of Scx-lineage cells as a key cellular mechanism of neonatal healing that is absent in adults. Instead, adult Scx-lineage tenocytes are not recruited into the defect but transdifferentiate into ectopic cartilage; in the absence of tenogenic cells, extrinsic αSMA-expressing cells persist to form a permanent scar. Collectively, these results establish an exciting model of tendon regeneration and uncover a novel cellular mechanism underlying regenerative vs non-regenerative tendon healing. PMID:28332620

  15. Management of Giant Retinal Tear Detachments

    PubMed Central

    Berrocal, Maria H.; Chenworth, Megan L.; Acaba, Luis A.

    2017-01-01

    Giant retinal tears (GRTs) are full-thickness circumferential tears of more than 90 degrees of the retina that are associated with vitreous detachment. They are related to ocular trauma, high myopia, aphakia, pseudophakia, genetic mutations involving collagen and young age. GRTs comprise 1.5% of all rhegmatogenous retinal detachments and the average age of incidence is 42 years. GRTs are more common in males, as 72% of all cases occur in males. The incidence of GRTs in the general population is estimated to be 0.05 per 100,000 individuals. Common techniques used in the management of GRTs include fluid-air exchange, pneumatic retinopexy, scleral buckling, primary vitrectomy with gas or silicone oil tamponade, and combined scleral buckle-vitrectomies. However, management of GRTs poses a great challenge to physicians due to the high risk of intra- and post-operative complications and the many technical difficulties involved. The advent of perfluorocarbon liquids (PFCL) and the use of micro-incisional surgery for the treatment of GRTs has provided new opportunities for the management of GTRs. Today, retinal reattachment can be achieved in 94-100% of cases. PMID:28299011

  16. Tearing Mode Stability with Sheared Toroidal Flows

    NASA Astrophysics Data System (ADS)

    White, Ryan; Coppi, Bruno

    2016-10-01

    Toroidal plasma flow induced by neutral beam heating has been found to increase the stability of tearing modes in tokamak plasmas. The need to extrapolate current (experimentally-based) knowledge of tearing mode onset to future machines, requiresa better understanding of the essential physics. We consider the physics of flow near the rational surfaces. For realistic flow profiles, the velocity shear near the rational surface can be treated as a perturbation, and is found to amplify the dominant stabilizing effect of magnetic curvature. This effect can be seen using a cylindrical model if large-aspect-ratio corrections to the magnetic curvature are incorporated. On the other hand, the physical effects of toroidal rotation are completely absent in a cylinder, and require a fully-toroidal calculation to study. The toroidal rotation near the rational surface is found to couple to a geometrical parameter which vanishes for up-down symmetric profiles. Physically, the dominant effects of rotation arise from a Coriolis force, leading to flow directional dependence. This work is supported by the US DOE.

  17. Rotator Cuff Tears in the Elderly Patients

    PubMed Central

    Geary, Michael B.

    2015-01-01

    Rotator cuff tears (RCT) are a common clinical problem in the geriatric population, and debate exists over how to best provide pain relief and restore shoulder function. Treatment options can be broadly divided into nonsurgical and surgical, with the majority of patients initially placed on a trial of conservative therapy. For those with irreparable RCT, low functional demand, or interest in nonoperative management, there are a number of nonsurgical treatments to consider, including rehabilitation and injections of corticosteroids, hyaluronate, and platelet-rich plasma. Surgical treatment is increasingly common, as geriatric patients remain active with high functional demands. Studies in elderly populations have demonstrated satisfactory healing and clinical results following surgical repair. Predictors of poor outcome after repair are large tear size as well as higher stages of fatty infiltration. Decompression is a less invasive surgical option that has been shown to provide short-term pain relief, though the lasting effects may deteriorate over time. A number of factors must be weighed when considering which patients are likely to benefit from surgical intervention. PMID:26328240

  18. Extensor-tendons reconstruction using autogenous palmaris longus tendon grafting for rheumatoid arthritis patients

    PubMed Central

    Chu, Po-Jung; Lee, Hung-Maan; Hou, Yao-Tung; Hung, Sheng-Tsai; Chen, Jung-Kuei; Shih, Jui-Tien

    2008-01-01

    Background The purpose of the study is to retrospectively review the clinical outcome of our study population of middle-aged RA patients who had suffered extensor-tendon rupture. We reported the outcome of autogenous palmaris tendon grafting of multiple extensor tendons at wrist level in 14 middle-aged rheumatoid patients. Methods Between Feb. 2000 to Feb. 2004, thirty-six ruptured wrist level extensor tendons were reconstructed in fourteen rheumatoid patients (11 women and three men) using autogenous palmaris longus tendon as a free interposition graft. In each case, the evaluation was based on both subjective and objective criteria, including the range of MCP joint flexion after surgery, the extension lag at the metacarpophalangeal joint before and after surgery, and the ability of the patient to work. Results and Discussion The average of follow-up was 54.1 months (range, 40 to 72 months). The average range of MCP joint flexion after reconstruction was 66°. The extension lag at the metacarpophalangeal joint significantly improved from a preoperative mean of 38° (range, 25°–60°) to a postoperative mean of 16° (range, 0°–30°). Subjectively all patients were satisfied with the clinical results, and achieved a return to their level of ability before tendon rupture. We found good functional results in our series of interposition grafting using palmaris longus to reconstruct extensor tendon defects in the rheumatoid patients. Conclusion Reconstruction for multiple tendon ruptures is a salvage procedure that is often associated with extensor lag and impairment of overall function. Early aggressive treatment of extensor tendon reconstruction using autogenous palmaris longus tendon as a free interposition graft in the rheumatoid wrist is another viable option to achieve good clinical functional result. PMID:18435845

  19. 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.

  20. Arthroscopic suture bridge technique for intratendinous tear of rotator cuff in chronically painful calcific tendinitis of the shoulder.

    PubMed

    Ji, Jong-Hun; Shafi, Mohamed; Moon, Chang-Yun; Park, Sang-Eun; Kim, Yeon-Jun; Kim, Sung-Eun

    2013-11-01

    Arthroscopic removal, now the main treatment option, has almost replaced open surgery for treatment of resistant calcific tendinitis. In some cases of chronic calcific tendinitis of the shoulder, the calcific materials are hard and adherent to the tendon. Removal of these materials can cause significant intratendinous tears between the superficial and deep layers of the degenerated rotator cuff. Thus far, there are no established surgical techniques for removing the calcific materials while ensuring cuff integrity. Good clinical results for rotator cuff repair were achieved by using an arthroscopic suture bridge technique in patients with long-standing calcific tendinitis. Intact rotator cuff integrity and recovery of signal change on follow-up magnetic resonance imaging scans were confirmed. This is a technical note about a surgical technique and its clinical results with a review of relevant published reports.

  1. Measurement of Tear Production in English Angora and Dutch Rabbits.

    PubMed

    Rajaei, Seyed Mehdi; Rafiee, Siamak Mashhady; Ghaffari, Masoud Selk; Masouleh, Mohammad N; Jamshidian, Mahmoud

    2016-03-01

    The purpose of this study was to establish normal values for tear production tests in different breeds of domestic rabbits. Healthy adult rabbits (n = 60; 120 eyes) of 2 different breeds (English angora and Dutch; n = 15 of each sex and breed) were used in this study. Tear production was measured by using the 1-min Schirmer tear test (STT), phenol red thread test (PRTT), and endodontic absorbent paper point tear test (EAPTT). In addition, horizontal palpebral fissure length was evaluated as a measure of ocular adnexal dimensions. Tear production (mean ± 1 SD) in English angora rabbits was 5.4 ± 1.6 mm/min according to the STT, 25.0 ± 2.7 mm in 15 s for the PRTT, and 18.8 ± 2.1 mm/min by the EAPTT; in Dutch rabbits, these values were 4.6 ± 1.2 mm/min, 23.6 ± 2.3 mm in 15 s, and 16.9 ± 1.7 mm/min, respectively. Only the EAPTT revealed a significant difference in tear production between English Angora and Dutch rabbits. These results provide reference values for tear production in English Angora and Dutch rabbits according to 3 different quantitative tear film assessment methods.

  2. The effect of line-tying on tearing modes

    SciTech Connect

    Delzanno, Gian Luca; Finn, John M.

    2008-03-15

    Cylindrical magnetohydrodynamic (MHD) constant-{psi} or nonconstant-{psi} tearing modes that are linearly unstable with periodic axial boundary conditions are studied in a line-tied cylinder. Examples of these two respective classes of modes, with m=1 and m=2 (m being the azimuthal mode number), are studied. With a suitable MHD equilibrium, the former modes are marginally stable in ideal MHD for periodic axial boundary conditions, and occur as fast tearing modes (resistive kinks) in the presence of resistivity {eta}. The latter modes are stable in ideal MHD for periodic axial boundary conditions, and with resistivity occur as constant-{psi} tearing modes, unstable in a range of parameters. In both cases, the results for the line-tied modes show the expected tearing scaling with {eta} for very long plasmas, but the scaling becomes {gamma}{proportional_to}{eta} for smaller cylinder lengths L. These results are consistent with the following interpretation: For L{yields}{infinity}, the modes have a tearing width characteristic of tearing, leading to characteristic tearing mode growth. As L decreases, the modes develop a geometric width, which increases as L decreases; the {gamma}{proportional_to}{eta} scaling occurs when L is small enough that the geometric width exceeds the tearing width.

  3. Tear Film Dynamics: the roles of complex structure and rheology

    NASA Astrophysics Data System (ADS)

    Dey, Mohar; Feng, James; Vivek, Atul S.; Dixit, Harish N.; Richhariya, Ashutosh

    2016-11-01

    Ocular surface infections such as microbial and fungal keratitis are among leading causes of blindness in the world. A thorough understanding of the pre-corneal tear film dynamics is essential to comprehend the role of various tear layer components in the escalation of such ocular infections. The pre-corneal tear film comprises of three layers of complex fluids, viz. the innermost mucin layer, a hydrophilic protective cover over the sensitive corneal epithelium, the intermediate aqueous layer that forms the bulk of the tear film and is often embedded with large number of bio-polymers either in the form of soluble mucins or pathogens, and finally the outermost lipid layer that stabilizes the film by decreasing the air/tear film interfacial tension. We have developed a comprehensive mathematical model to describe such a film by incorporating the effects of the non-uniform mucin distribution along with the complex rheology of the aqueous layer with/without pathogens, Marangoni effects from the lipid layer and the slip effects at the base of the tear film. A detailed linear stability analysis and a fully non-linear solution determine the break up time (BUT) of such a tear film. We also probe the role of the various components of the pre-corneal tear film in the dynamics of rupture.

  4. State Secret: North Carolina and the Cherokee Trail of Tears

    ERIC Educational Resources Information Center

    Bryant, James

    2008-01-01

    This paper is an analytic essay that examines the treatment of the Cherokee Trail of Tears in a North Carolina fourth grade textbook. I begin by offering a satiric look at an imaginary textbook's treatment of the Holocaust that is based closely on the actual narrative of the Trail of Tears written in the fourth grade text. Following this, close…

  5. Specialization of tendon mechanical properties results from interfascicular differences

    PubMed Central

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

    2012-01-01

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

  6. Outcome of arthroscopic subscapularis tendon repair: Are the results improving with improved techniques and equipment?: A retrospective case series

    PubMed Central

    Arun, G R; Kumar, Pradeep; Patnaik, Sarthak; Selvaraj, Karthik; Rajan, David; Singh, Anant; Kumaraswamy, Vinay

    2016-01-01

    Background: Rotator cuff tears are a common cause of shoulder pain and dysfunction. More recently, there has been a renewed interest in understanding the subscapularis tears. There are multiple articles in the literature showing the short term results of isolated subscapularis tendon repair. However, the midterm and long term outcome studies for arthroscopic subscapularis repair are few. This study evaluates the functional outcome after arthroscopic subscapularis repair. Materials and Methods: The records of 35 patients who underwent an arthroscopic subscapularis repair between May 2008 and June 2012 were included in this retrospective study. The records of all patients were reviewed. There were 22 males and 13 female patients with mean age of 58.2 years (range 41-72 years). All patients had a complete history, physical examination, and radiographs of their shoulders. Visual analogue scale (VAS), range of movements, power of cuff muscles, and modified University of California at Los Angeles (UCLA) score were assessed. Results: The mean followup was 2.8 years (range 2-4 year). Functional outcome after arthroscopic subscapularis repair has an excellent outcome as analysed by clinical outcome, VAS score and UCLA score. Results were analyzed and had statistically significant values. The VAS for pain improved significantly (P < 0.001), and the mean modified UCLA score improved significantly (P < 0.001) from 14.24 ± 4.72 preoperatively to 33.15 ± 2.29 at 2 years postoperative. According to the UCLA system, there were 22 excellent, 11 good, and 2 fair results. Around 95% of patients returned to their usual work after surgery. Conclusion: At a median followup of 2 years, 95% of patients had a good to excellent result after an arthroscopic subscapularis tendon repair. We conclude that the midterm results show that arthroscopic subscapularis repair remains a good option for the treatment of patients with subscapularis tendon repair. PMID:27293291

  7. [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.

  8. Gyrokinetic Simulation of Low-n Tearing Modes

    NASA Astrophysics Data System (ADS)

    Chen, Yang

    2015-11-01

    Direct gyrokinetic simulation of the low-n tearing mode in a tokamak plasma has been a great computational challenge, for two reasons. First, low-n tearing modes, unlike the micro-tearing modes, have very small growth rates and very fine mode structure in the tearing layer, which requires a large number of radial grid cells and fine control of numerical dissipation. Second, kinetic electron effects are needed in the tearing layer. Here, we first present linear gyrokinetic simulation of the low-n tearing mode in cylindrical geometry. Ions are gyrokinetic and electrons are either drift kinetic or fluid. New field solvers have been developed in the gyrokinetic code GEM [Chen and Parker, J. Comput. Phys. 220, 839 (2007)] to simulate low-n modes. For the fluid electron model, an eigenmode analysis with finite Larmor radius effects has been developed to study the linear resistive tearing mode. Excellent agreement between eigenmode analysis and initial value gyrokinetic simulation is obtained. The mode growth rate is shown to scale with resistivity as η 1 / 3, the same as the semi-collisional regime in previous kinetic treatments. Simulation of the collisionless and semi-collisional tearing mode with drift kinetic electrons has been carried out with GEM's direct split-weight control-variate algorithm. It is found that a full torus simulation of the m=2, n=1 tearing mode in a present day large tokamak is still difficult with kinetic electrons, but a generalized matching technique can be used to ameliorate the problem. The radial dimension is divided into an external region and the tearing region, with the external region described by a reduced model that gives the boundary condition for the tearing region. The size of the tearing region is small compared with the minor radius, but not arbitrarily small as done in the standard asymptotic matching approach. Gyrokinetic simulation verifies the collisionless tearing mode growth rate with finite electron mass, the semi

  9. Effect of Airflow Exposure on the Tear Meniscus

    PubMed Central

    Koh, Shizuka; Tung, Cynthia; Kottaiyan, Ranjini; Zavislan, James; Yoon, Geunyoung; Aquavella, James

    2012-01-01

    Purpose. To compare the effect of airflow exposure on the tear meniscus and blink frequency in normal and evaporative dry eye subjects. Methods. In 9 normal subjects and 9 short tear breakup time (SBUT) dry eye subjects, lower tear meniscus height (TMH) and area (TMA) and blink frequency were measured with anterior segment optical coherence tomography (OCT) before and after 5 minutes of airflow exposure (1.5 ± 0.5 m/s). Results. In SBUT dry eyes, both TMH and TMA decreased significantly (P = 0.027, P = 0.027) with a significant increase of blink frequency after airflow exposure, while significant increase in TMA was found in normal eyes. Conclusion. Measurement of the tear meniscus with anterior segment OCT seems to be useful as a noninvasive and objective method for evaluating the effect of airflow on tear film. PMID:22570766

  10. Preliminary Results of a Consecutive Series of Large & Massive Rotator Cuff Tears Treated with Arthroscopic Rotator Cuff Repairs Augmented with Extracellular Matrix

    PubMed Central

    Consigliere, Paolo; Polyzois, Ioannis; Sarkhel, Tanaya; Gupta, Rohit; Levy, Ofer; Narvani, A. Ali

    2017-01-01

    Background: Recurrence rate of rotator cuff tears is still high despite the improvements of surgical techniques, materials used and a better knowledge of the healing process of the rotator cuff tendons. Large to massive rotator cuff tears are particularly associated with a high failure rate, especially in elderly. Augmentation of rotator cuff repairs with extracellular matrix or synthetic patches has gained popularity in recent years with the aim of reducing failure. The aim of this study was to investigate the outcome of rotator cuff repairs augmented with denatured extracellular matrix in a series of patients who underwent arthroscopic rotator cuff repair for large to massive tears. Methods: Ten consecutive patients, undergoing arthroscopic rotator cuff repair with extracellular matrix augment for large and massive tears, were prospectively enrolled into this single surgeon study. All repairs were performed arthroscopically with a double row technique augmented with extracellular matrix. Oxford Shoulder Score, Constant Score and pain visual analogue scale (VAS) were used to monitor the shoulder function and outcome pre-operatively and at three, six and 12-month follow-up. Minimum follow up was three months. Mean follow up was 7 months. Results: Mean Constant score improved from 53 (SD=4) pre-operatively to 75 (SD=11) at final follow up. Mean Oxford score also increased from 30 (SD=8) pre-operatively to 47 (SD=10) at the final follow up. The visual analogue scale (VAS) improved from seven out of 10 (SD=2) preoperatively to 0.6 (SD=0.8) at final follow up. Additionally, there was significant improvement at three months mark in Constant score. Conclusion: Arthroscopic repair and augmentation of large and massive rotator cuff tears with extracellular matrix patch has good early outcome. PMID:28271082

  11. 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

  12. 'Bald trochanter' spontaneous rupture of the conjoined tendons of the gluteus medius and minimus presenting as a trochanteric bursitis.

    PubMed

    LaBan, Myron M; Weir, Susan K; Taylor, Ronald S

    2004-10-01

    A 66-yr-old white woman presented with progressive complaints of right lateral hip and thigh pain associated with a disabling limp without an antecedent history of trauma. Physical examination revealed localized pain over the right greater trochanter to palpation. A full pain-free range of motion of the right hip was associated with weakness in the hip abductors. The patient ambulated with a compensated right Trendelenburg gait. Subsequent magnetic resonance imaging demonstrated a trochanteric bursitis and an effusion of the hip and a full-thickness tear of the gluteus medius muscle, with both a disruption and retraction of the tendon of an atretic gluteus minimus muscle. Conjoined tendon pathology of both the gluteus medius and minimus as, revealed by magnetic resonance examination, is probably more frequent than heretofore commonly recognized. In patients presenting with "intractable" complaints of a trochanteric bursitis and an ambulatory limp due to weakness in the hip abductors, imaging studies calling attention to a possible tendon rupture may be diagnostic.

  13. 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.

  14. Closed Zone III Rupture of the Flexor Digitorum Profundus Tendons of the Right Index, Long, and Ring Fingers in a Bowler: Gutterball Syndrome.

    PubMed

    Ostric, Srdjan Andrei; Russell, Robert C; Petrungaro, Jason

    2010-12-01

    Zone III flexor tendon injuries are relatively rare in comparison to other flexor tendon injuries in zones I, II, IV, and V. Often, these are open injuries resulting from an electrical device like a saw; however, closed injures are even rarer, and those mid-substance ruptures resulting from bowling with no evidence of underlying tendinopathy from diseases like gout are highly unusual. The principles underlying tendon repair remain the same regardless of the etiology. In this case, we delineate some of the options and stress the guiding principles of the various methods available in this interesting and unusual case.

  15. Robot Arm with Tendon Connector Plate and Linear Actuator

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

  16. Nutritional research may be useful in treating tendon injuries.

    PubMed

    Curtis, Luke

    2016-06-01

    Tendon injures cause a great deal of disability and pain, and increase medical costs. However, relatively little is known about tendon biology and healing. Many tendon-related surgical procedures are not very successful and leave the patient with essentially a chronic injury. New therapeutic approaches for tendon injury are needed. Preliminary evidence suggests that various nutrients such as proteins, amino acids (leucine, arginine, glutamine), vitamins C and D, manganese, copper, zinc, and phytochemicals may be useful in improving tendon growth and healing. More research on nutrition and tendon health is needed. Because many nutrients are required for tendon health, nutritional interventions involving multiple nutrients may be more effective than single-nutrient strategies. In the future, ideal treatment regimens for tendon injuries may include a multifaceted "bundle" of nutrition, drugs, biologic products, extracellular matrix therapies, exercise/physical therapy, and possibly surgery.

  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. 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

  19. Modelling approaches for evaluating multiscale tendon mechanics

    PubMed Central

    Fang, Fei; Lake, Spencer P.

    2016-01-01

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

  20. No Telescoping Effect with Dual Tendon Vibration

    PubMed Central

    Bellan, Valeria; Wallwork, Sarah B.; Stanton, Tasha R.; Reverberi, Carlo; Gallace, Alberto; Moseley, G. Lorimer

    2016-01-01

    The tendon vibration illusion has been extensively used to manipulate the perceived position of one’s own body part. However, findings from previous research do not seem conclusive sregarding the perceptual effect of the concurrent stimulation of both agonist and antagonist tendons over one joint. On the basis of recent data, it has been suggested that this paired stimulation generates an inconsistent signal about the limb position, which leads to a perceived shrinkage of the limb. However, this interesting effect has never been replicated. The aim of the present study was to clarify the effect of a simultaneous and equal vibration of the biceps and triceps tendons on the perceived location of the hand. Experiment 1 replicated and extended the previous findings. We compared a dual tendon stimulation condition with single tendon stimulation conditions and with a control condition (no vibration) on both ‘upward-downward’ and ‘towards-away from the elbow’ planes. Our results show a mislocalisation towards the elbow of the position of the vibrated arm during dual vibration, in line with previous results; however, this did not clarify whether the effect was due to arm representation contraction (i.e., a ‘telescoping’ effect). Therefore, in Experiment 2 we investigated explicitly and implicitly the perceived arm length during the same conditions. Our results clearly suggest that in all the vibration conditions there was a mislocalisation of the entire arm (including the elbow), but no evidence of a contraction of the perceived arm length. PMID:27305112

  1. 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.

  2. Structure-function relationships in tendons: a review

    PubMed Central

    Benjamin, M; Kaiser, E; Milz, S

    2008-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  4. Comparison of desired radiographic advancement distance and true advancement distance required for patellar tendon-tibial plateau angle reduction to the ideal 90° in dogs by use of the modified Maquet technique.

    PubMed

    Pillard, Paul; Livet, Veronique; Cabon, Quentin; Bismuth, Camille; Sonet, Juliette; Remy, Denise; Fau, Didier; Carozzo, Claude; Viguier, Eric; Cachon, Thibaut

    2016-12-01

    OBJECTIVE To evaluate the validity of 2 radiographic methods for measurement of the tibial tuberosity advancement distance required to achieve a reduction in patellar tendon-tibial plateau angle (PTA) to the ideal 90° in dogs by use of the modified Maquet technique (MMT). SAMPLE 24 stifle joints harvested from 12 canine cadavers. PROCEDURES Radiographs of stifle joints placed at 135° in the true lateral position were used to measure the required tibial tuberosity advancement distance with the conventional (A(M)) and correction (A(E)) methods. The MMT was used to successively advance the tibial crest to A(M) and A(E). Postoperative PTA was measured on a mediolateral radiograph for each advancement measurement method. If none of the measurements were close to 90°, the advancement distance was modified until the PTA was equal to 90° within 0.1°, and the true advancement distance (TA) was measured. Results were used to determine the optimal commercially available size of cage implant that would be used in a clinical situation. RESULTS Median A(M) and A(E) were 10.6 mm and 11.5 mm, respectively. Mean PTAs for the conventional and correction methods were 93.4° and 92.3°, respectively, and differed significantly from 90°. Median TA was 13.5 mm. The A(M) and A(E) led to the same cage size recommendations as for TA for only 1 and 4 stifle joints, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Both radiographic methods of measuring the distance required to advance the tibial tuberosity in dogs led to an under-reduction in postoperative PTA when the MMT was used. A new, more accurate radiographic method needs to be developed.

  5. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Identification. A passive tendon prosthesis is a device intended to be implanted made of silicon elastomer or a... flexor tendon of the hand. The device is implanted for a period of 2 to 6 months to aid growth of a new tendon sheath. The device is not intended as a permanent implant nor to function as a replacement for...

  6. Tibialis posterior tendon rupture: a cause of rheumatoid flat foot.

    PubMed

    Downey, D J; Simkin, P A; Mack, L A; Richardson, M L; Kilcoyne, R F; Hansen, S T

    1988-03-01

    Flat foot, a major cause of foot pain and disability, may result from rupture of the tibialis posterior tendon. We describe 2 patients with rheumatoid arthritis who developed flat feet secondary to surgically confirmed tendon rupture, and we discuss the anatomy and diagnosis of this condition. In the second patient, we also present the results of tendon imaging with both magnetic resonance and ultrasound.

  7. An Overview of the Management of Flexor Tendon Injuries

    PubMed Central

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

    2012-01-01

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

  8. Biodegradable synthetic scaffolds for tendon regeneration

    PubMed Central

    Reverchon, Ernesto; Baldino, Lucia; Cardea, Stefano; De Marco, Iolanda

    2012-01-01

    Summary Tissue regeneration is aimed at producing biological or synthetic scaffolds to be implanted in the body for regenerate functional tissues. Several techniques and materials have been used to obtain biodegradable synthetic scaffolds, on which adhesion, growth, migration and differentiation of human cells has been attempted. Scaffolds for tendon regeneration have been less frequently proposed, because they have a complex hierarchical structure and it is very difficult to mimic their peculiar mechanical properties. In this review, we critically analyzed the proposed materials and fabrication techniques for tendon tissue engineering and we indicated new preparation processes, based on the use of supercritical fluids, to produce scaffolds with characteristics very similar to the native tendon structure. PMID:23738295

  9. Gyrokinetic simulations of the tearing instability

    SciTech Connect

    Numata, Ryusuke; Dorland, William; Howes, Gregory G.; Loureiro, Nuno F.; Tatsuno, Tomoya

    2011-11-15

    Linear gyrokinetic simulations covering the collisional-collisionless transitional regime of the tearing instability are performed. It is shown that the growth rate scaling with collisionality agrees well with that predicted by a two-fluid theory for a low plasma beta case in which ion kinetic dynamics are negligible. Electron wave-particle interactions (Landau damping), finite Larmor radius, and other kinetic effects invalidate the fluid theory in the collisionless regime, in which a general non-polytropic equation of state for pressure (temperature) perturbations should be considered. We also vary the ratio of the background ion to electron temperatures and show that the scalings expected from existing calculations can be recovered, but only in the limit of very low beta.

  10. Blepharophimosis syndrome with absent tear production.

    PubMed

    Ng, Jacqueline K; Stout, Ann U; Aaby, Aazy A; Ng, John D

    2015-01-01

    The purpose of this report was to present a case of congenital alacrima in a patient with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES). A 9-month-old boy presented with characteristic clinical findings of BPES confirmed by genetic testing. On further history taking and evaluation, the patient was noted to have no tear production, despite clinically present palpebral lobes of the lacrimal glands. BPES is an autosomal dominant condition characterized by narrowed horizontal palpebral fissures, severe bilateral symmetric ptosis, epicanthus inversus, and telecanthus. To the authors' knowledge, this represents the second reported case of congenital alacrima in this syndrome. The first case described in the literature was in a 9-month-old girl who had congenital absence of the lacrimal glands. BPES may present with alacrima requiring vigilant lifelong lubrication and careful consideration in decisions for eyelid surgery including ptosis repair.

  11. Effects of tear gases on the eye.

    PubMed

    Kim, Yonwook J; Payal, Abhishek R; Daly, Mary K

    2016-01-01

    Chemical agents that target the eyes have been a popular choice for law enforcement during riots and for military training for nearly a century. The most commonly used agents are chloroacetophenone (formerly sold as Mace), o-chlorobenzylidene malononitrile, and oleoresin capsicum (OC or pepper spray, current ingredient for Mace). Initially, most severe ocular injuries were caused by the explosive force rather than the chemical itself. The development of sprays reduced the mechanical severity of ocular injuries, but resulted in a variety of chemical injuries. The effects on eyes include conjunctival injection, complete corneal epithelial defects, pseudopterygium, corneal neovascularization, persistent conjunctivalization, corneal opacities, and reduced visual acuity. Current management, based on limited human studies, emphasizes decontamination and symptomatic treatment. We review the literature related to clinical and histopathologic effects of tear gas agents on the eye and their management.

  12. Observation of Spontaneous Neoclassical Tearing Modes

    SciTech Connect

    E.D. Fredrickson

    2001-10-03

    We present data in this paper from the Tokamak Fusion Test Reactor (TFTR) which challenges the commonly held belief that extrinsic MHD events such as sawteeth or ELMs [edge localized modes] are required to provide the seed islands that trigger Neoclassical Tearing Modes (NTMs). While sawteeth are reported to provide the trigger for most of the NTMs on DIII-D [at General Atomics in San Diego, California] and ASDEX-U [at Max-Planck-Institut fuer Plasmaphysik in Garching, Germany], the majority of NTMs seen in TFTR occur in plasmas without sawteeth, that is which are above the beta threshold for sawtooth stabilization. Examples of NTMs appearing in the absence of any detectable extrinsic MHD activity will be shown. Conversely, large n=1 modes in plasmas above the NTM beta threshold generally do not trigger NTMs. An alternative mechanism for generating seed islands will be discussed.

  13. Crocodile tears and thread test of lacrimation.

    PubMed

    Yagi, N; Nakatani, H

    1986-01-01

    Patients with incomplete recovery from peripheral facial paralysis often complain of eye-watering while eating (crocodile tears or gustolacrimal reflex). In 55 patients (22 completely recovered from peripheral facial paralysis, 23 incompletely recovered, and ten with hemifacial spasm), lacrimation was monitored by the thread test (a modification of the Schirmer test) during taste stimulation. In the 22 patients with complete recovery, the results of the thread test did not differ before and after a sweet-sour candy was given (taste stimulation). All the patients with incomplete recovery showed either synkinesis or contracture. Lacrimation on the side of the lesion was high even before taste stimulation. After taste stimulation, a rapid and definite increase in lacrimation was observed. The results show that in patients with synkinesis and incomplete recovery after peripheral facial paralysis, the misdirected regeneration of the injured nerve fiber often occurs from the gustatory nerve to the lacrimal nerve, as well as between motor fibers.

  14. Energy balance of the collisional tearing mode

    SciTech Connect

    Bondeson, A.; Sobel, J.R.

    1984-08-01

    The energy balance of the collisional tearing mode is examined within linear theory. It is found that in an asymmetric case the quadratic form given by Furth for the net release of magnetic energy must be completed with a term connected with the current gradient in the resistive layer. The growth-rate and the inner-layer solution are calculated in the limit where viscosity dominates over inertia. The amounts of energy going into Joule heating and either kinetic energy or viscous dissipation are calculated analytically. In the inertial regime 1/4 of the net decrease in magnetic energy goes into kinetic energy and (3)/(4) into Joule heating, while, in viscous regime, (1)/(6) goes into viscous dissipation and (5)/(6) into Joule heating. The analytical results, based on the constant-psi approximation, are in good agreement with numerical simulations when the resistive layer is sufficiently narrow.

  15. Viscoplastic tearing of polyethylene thin film

    NASA Astrophysics Data System (ADS)

    Hegyi, Dezso; Pellegrino, Sergio

    2015-05-01

    Recent advances in noncontact strain measurement techniques and large-strain constitutive modeling of the linear low-density polyethylene film used in NASA superpressure balloons StratoFilm 420 are combined to provide a novel measurement technique for the tear propagation critical value of the J-integral. Previously these measurements required complex test configurations and procedures. It is found that the critical value of the J-integral increases by approximately 50 % when the strain rate is decreased from 1.33×10-4 s-1 to 1.33×10-5 s-1. It is shown that there is good correlation between measurements made on uniaxially loaded dogbone samples and circular diaphragms loaded by pressure, both with a 2-mm-wide slit in the middle. This result indicates that more extensive studies of strain-rate dependence may be made with the simpler, uniaxial test configuration.

  16. Can Grafts Provide Superior Tendon Healing and Clinical Outcomes After Rotator Cuff Repairs?

    PubMed Central

    Ono, Yohei; Dávalos Herrera, Diego Alejandro; Woodmass, Jarret M.; Boorman, Richard S.; Thornton, Gail M.; Lo, Ian K. Y.

    2016-01-01

    Background: Arthroscopic repair of large to massive rotator cuff tears commonly retear. To improve healing rates, a number of different approaches have been utilized, including the use of grafts, which may enhance the biomechanical and biologic aspects of the repair construct. However, the outcomes after the use of grafts are diverse. Purpose: To systematically review the literature for large to massive rotator cuff tears to determine whether the use of grafts generally provides superior tendon healing and clinical outcomes to the repairs without grafts. Study Design: Systematic review; Level of evidence, 3. Methods: A systematic review of the literature was performed. Clinical studies comparing the repairs with (graft group) and without grafts (control group) were included and analyzed. The primary outcome was tendon healing on either magnetic resonance imaging or ultrasound. The secondary outcome measures included visual analog scale for pain, University of California at Los Angles (UCLA) score, and forward elevation range. Differences between groups in all outcome measures were statistically analyzed. Results: Six comparative studies (level of evidence 2 or 3) with 13 study groups were included. A total of 242 repairs in the graft group (mean age, 62.5 ± 4.6 years) and 185 repairs in the control group (mean age, 62.5 ± 5.0 years) were analyzed. The graft types utilized included autograft (fascia lata) in 1 study, allograft (human dermis) in 2 studies, xenograft (bovine pericardium, porcine small intestine submucosa) in 2 studies, synthetic graft (polypropylene) in 1 study, and a combination of autograft (the long head of biceps) and synthetic graft (polypropylene) in 1 study. The overall mean follow-up time was 28.4 ± 9.0 months. When 1 or 2 studies/study groups were excluded due to practical or statistical reasons, the graft group demonstrated significantly improved healing (odds ratio, 2.48; 95% CI, 1.58-3.90; P < .0001) and all clinical outcome measures at

  17. Tear Mediators in Corneal Ectatic Disorders

    PubMed Central

    Pásztor, Dorottya; Kolozsvári, Bence Lajos; Csutak, Adrienne; Berta, András; Hassan, Ziad; Ujhelyi, Bernadett; Gogolák, Péter; Fodor, Mariann

    2016-01-01

    Purpose To compare the concentrations of 11 tear mediators in order to reveal the biochemical difference between pellucid marginal degeneration (PMD) and keratoconus (KC). Methods We have designed a cross-sectional study in which patients with corneal ectasia based on slit-lamp biomicroscopy and Pentacam HR (keratometry values (K1, K2, Kmax), astigmatism, minimal radius of curvature (Rmin), corneal thickness (Apex and Min), indices (surface variation, vertical asymmetry, keratoconus, central keratoconus, height asymmetry and decentration)) were enrolled. Eyes of keratoconic patients were similar to the PMD patients in age and severity (K2, Kmax and Rmin). Non-stimulated tear samples were collected from nine eyes of seven PMD patients, 55 eyes of 55 KC patients and 24 eyes of 24 healthy controls. The mediators’ (interleukin -6, -10, chemokine ligand 5, -8, -10, matrix metalloproteinase (MMP) -9, -13, tissue inhibitor of metalloproteinases (TIMP)-1, tissue plasminogen activator, plasminogen activator inhibitor, nerve growth factor) concentrations were measured using Cytometric Bead Array. Results MMP-9 was the only mediator which presented relevant variances between the two patient groups (p = 0.005). The ratios of MMP-9 and TIMP-1 were 2.45, 0.40 and 0.23 in PMD, KC and the controls, respectively. Conclusion As far as we are aware, this is the first study that aims to reveal the biochemical differences between PMD and KC. Further studies of biomarkers to investigate the precise role of these mediators need to be defined, and it is important to confirm the observed changes in a larger study to gain further insights into the molecular alterations in PMD. PMID:27074131

  18. Tear film lipid layer: A molecular level view.

    PubMed

    Cwiklik, Lukasz

    2016-10-01

    Human cornea is covered by an aqueous tear film, and the outermost layer of the tear film is coated by lipids. This so-called tear film lipid layer (TFLL) reduces surface tension of the tear film and helps with the film re-spreading after blinks. Alterations of tear lipids composition and properties are related to dry eye syndrome. Therefore, unveiling structural and functional properties of TFLL is necessary for understanding tear film function under both normal and pathological conditions. Key properties of TFLL, such as resistance against high lateral pressures and ability to spread at the tear film surface, are directly related to the chemical identity of TFLL lipids. Hence, a molecular-level description is required to get better insight into TFLL properties. Molecular dynamics simulations are particularly well suited for this task and they were recently used for investigating TFLL. The present review discusses molecular level organization and properties of TFLL as seen by these simulation studies. This article is part of a Special Issue entitled: Biosimulations edited by Ilpo Vattulainen and Tomasz Róg.

  19. Acute flexor tendon repairs in zone II.

    PubMed

    Coats, Robert W; Echevarría-Oré, Julio C; Mass, Daniel P

    2005-05-01

    Flexor tendon repair in zone II is still a technically demanding procedure, but the outcomes have become more predictable and satisfying. Of keystone importance for obtaining the goals of normal strength and gliding of repaired flexor tendons are an atraumatic surgical technique, an appropriate suture material, a competent pulley system, and the use of early motion rehabilitation protocols. The overall goal of hand and finger function also implies timely addressing of neurovascular injuries. New devices such as the TenoFix (Ortheon Medical; Winter Park, Florida) have shown adequate strength in the laboratory but are bulky and untested for work of flexion. Insufficient clinical data and high cost may prevent widespread use.

  20. Flexor Tendon Pulley Injuries in Rock Climbers.

    PubMed

    King, Elizabeth A; Lien, John R

    2017-02-01

    Closed pulley ruptures are rare in the general population but occur more frequently in rock climbers due to biomechanical demands on the hand. Injuries present with pain and swelling over the affected pulley, and patients may feel or hear a pop at the time of injury. Sequential pulley ruptures are required for clinical bowstringing of the flexor tendons. Ultrasound confirms diagnosis of pulley rupture and evaluates degree of displacement of the flexor tendons. Isolated pulley ruptures frequently are treated conservatively with early functional rehabilitation. Sequential pulley ruptures require surgical reconstruction. Most climbers are able to return to their previous activity level.

  1. Tendon ruptures: mallet, flexor digitorum profundus.

    PubMed

    Yeh, Peter C; Shin, Steven S

    2012-08-01

    Mallet injuries are the most common closed tendon injury in the athlete. Flexor digitorum profundus ruptures are rare in baseball, but are common injuries in contact sports. The diagnosis for each condition is based on clinical examination, although radiographs should be evaluated for a possible bony component. Treatment for mallet injury depends on the athlete's goals of competition and understanding of the consequences of any treatment chosen. Gripping, throwing, and catching would be restricted or impossible with the injured finger immobilized. Treatment of FDP ruptures is almost always surgical and requires reattachment of the torn tendon to the distal phalanx.

  2. [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

  3. The potential of optical coherence tomography in meniscal tear characterization

    NASA Astrophysics Data System (ADS)

    Ling, Hang-yin; Guo, Shuguang; Thieman, Kelley M.; Wise, Brent T.; Pozzi, Antonio; Xie, Huikai; Horodyski, MaryBeth

    2009-02-01

    Meniscal tear is one of the most common knee injuries leading to pain and discomfort. Partial and total meniscectomies have been widely used to treat the avascular meniscal injuries in which tears do not heal spontaneously. However, the meniscectomies would cause an alteration of the tibiofemoral contact mechanics resulting in progressive osteoarthritis (OA). To mitigate the progression of OA, maximal preservation of meniscal tissue is recommended. The clinical challenge is deciding which meniscal tears are amenable to repair and which part of damaged tissues should be removed. Current diagnosis techniques such as arthroscopy and magnetic resonance imaging can provide macrostructural information of menisci, but the microstructural changes that occur prior to the observable meniscal tears cannot be identified by these techniques. Serving as a nondestructive optical biopsy, optical coherence tomography (OCT), a newly developed imaging modality, can provide high resolution, cross-sectional images of tissues and has been shown its capabilty in arthroscopic evaulation of articular cartilage. Our research was to demonstrate the potential of using OCT for nondestructive characterization of the histopathology of different types of meniscal tears from clinical cases in dogs, providing a fundamental understanding of the failure mechanism of meniscal tears. First, cross-sectional images of torn canine menisci obtained from the OCT and scanning electronic microscopy (SEM) were be compared. By studying the organization of collegan fibrils in torn menisci from the SEM images, the feasibility of using OCT to characterize the organization of collegan fibrils was elucidated. Moreover, the crack size of meniscal tears was quantatitively measured from the OCT images. Changes in the crack size of the tear may be useful for understanding the failure mechanism of meniscal tears.

  4. 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.

  5. Onset Time of Nerve Block: A Comparison of Two Injection Locations in Patients Having Lower Leg/ Foot Surgery

    ClinicalTrials.gov

    2014-03-20

    Strain of Muscle and/or Tendon of Lower Leg; Fracture of Lower Leg; Crushing Injury of Lower Leg; Fracture Malunion - Ankle and/or Foot; Disorder of Joint of Ankle and/or Foot; Complete Tear, Ankle and/or Foot Ligament; Pathological Fracture - Ankle and/or Foot; Loose Body in Joint of Ankle and/or Foot

  6. Finite-distance singularities in the tearing of thin sheets.

    PubMed

    Bayart, E; Boudaoud, A; Adda-Bedia, M

    2011-05-13

    We investigate the interaction between two cracks propagating quasistatically in a thin sheet. Two different experimental geometries allow us to tear sheets by imposing an out-of-plane shear loading. A single tear propagates in a straight line independently of its position in the sheet. In contrast, we find that two tears converge along self-similar paths and annihilate each other. These finite-distance singularities display geometry-dependent similarity exponents, which we retrieve using scaling arguments based on a balance between the stretching and the bending of the sheet close to the tips of the cracks.

  7. Threshold condition for nonlinear tearing modes in tokamaks

    SciTech Connect

    Zabiego, M.F.; Callen, J.D.

    1996-03-01

    Low-mode-number tearing, mode nonlinear evolution is analyzed emphasizing the need for a threshold condition, to account for observations in tokamaks. The discussion is illustrated by two models recently introduced in the literature. The models can be compared with the available data and/or serve as a basis for planning some experiments in order to either test theory (by means of beta-limit scaling laws, as proposed in this paper) or attempt to control undesirable tearing modes. Introducing a threshold condition in the tearing mode stability analysis is found to reveal some bifurcation points and thus domains of intrinsic stability in the island dynamics operational space.

  8. [Traumatic and degenerative tendon lesions of the hand].

    PubMed

    Schöffl, V; Winkelmann, H-P

    2010-12-01

    Tendon lesions are the second most common injury in the hand and therefore an important factor in orthopedic patients. Most injuries are open injuries to the flexor or extensor tendons; nevertheless, also less frequent injuries such as damage to the functional system of tendon sheath and pulley or dull avulsions need to be considered. Besides the clinical examination, ultrasound and MRI have proven to be important diagnostic tools. In the postoperative course of flexor tendon injuries, the principle of early passive movement is important to trigger "intrinsic" tendon healing to guarantee a good outcome.

  9. The role of animal models in tendon research

    PubMed Central

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

    2014-01-01

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

  10. Mechanical properties of UV irradiated rat tail tendon (RTT) collagen.

    PubMed

    Sionkowska, Alina; Wess, Tim

    2004-04-01

    The mechanical properties of RTT collagen tendon before and after UV irradiation have been investigated by mechanical testing (Instron). Air-dried tendon were submitted to treatment with UV irradiation (wavelength 254 nm) for different time intervals. The changes in such mechanical properties as breaking strength and percentage elongation have been investigated. The results have shown, that the mechanical properties of the tendon were greatly affected by time of UV irradiation. Ultimate tensile strength and ultimate percentage elongation decreased after UV irradiation of the tendon. Increasing UV irradiation leads to a decrease in Young's modulus of the tendon.

  11. In vivo tear film thickness measurement and tear film dynamics visualization using spectral domain OCT and an efficient delay estimator

    NASA Astrophysics Data System (ADS)

    Aranha dos Santos, Valentin; Schmetterer, Leopold; Gröschl, Martin; Garhofer, Gerhard; Werkmeister, René M.

    2016-03-01

    Dry eye syndrome is a highly prevalent disease of the ocular surface characterized by an instability of the tear film. Traditional methods used for the evaluation of tear film stability are invasive or show limited repeatability. Here we propose a new noninvasive approach to measure tear film thickness using an efficient delay estimator and ultrahigh resolution spectral domain OCT. Silicon wafer phantoms with layers of known thickness and group index were used to validate the estimator-based thickness measurement. A theoretical analysis of the fundamental limit of the precision of the estimator is presented and the analytical expression of the Cramér-Rao lower bound (CRLB), which is the minimum variance that may be achieved by any unbiased estimator, is derived. The performance of the estimator against noise was investigated using simulations. We found that the proposed estimator reaches the CRLB associated with the OCT amplitude signal. The technique was applied in vivo in healthy subjects and dry eye patients. Series of tear film thickness maps were generated, allowing for the visualization of tear film dynamics. Our results show that the central tear film thickness precisely measured in vivo with a coefficient of variation of about 0.65% and that repeatable tear film dynamics can be observed. The presented method has the potential of being an alternative to breakup time measurements (BUT) and could be used in clinical setting to study patients with dry eye disease and monitor their treatments.

  12. Inhibition of PDGFR signaling prevents muscular fatty infiltration after rotator cuff tear in mice.

    PubMed

    Shirasawa, Hideyuki; Matsumura, Noboru; Shimoda, Masayuki; Oki, Satoshi; Yoda, Masaki; Tohmonda, Takahide; Kanai, Yae; Matsumoto, Morio; Nakamura, Masaya; Horiuchi, Keisuke

    2017-01-31

    Fatty infiltration in muscle is often observed in patients with sizable rotator cuff tear (RCT) and is thought to be an irreversible event that significantly compromises muscle plasticity and contraction strength. These changes in the mechanical properties of the affected muscle render surgical repair of RCT highly formidable. Therefore, it is important to learn more about the pathology of fatty infiltration to prevent this undesired condition. In the present study, we aimed to generate a mouse model that can reliably recapitulate some of the important characteristics of muscular fatty infiltration after RCT in humans. We found that fatty infiltration can be efficiently induced by a combination of the following procedures: denervation of the suprascapular nerve, transection of the rotator cuff tendon, and resection of the humeral head. Using this model, we found that platelet-derived growth factor receptor-α (PDGFRα)-positive mesenchymal stem cells are induced after this intervention and that inhibition of PDGFR signaling by imatinib treatment can significantly suppress fatty infiltration. Taken together, the present study presents a reliable fatty infiltration mouse model and suggests a key role for PDGFRα-positive mesenchymal stem cells in the process of fatty infiltration after RCT in humans.

  13. Inhibition of PDGFR signaling prevents muscular fatty infiltration after rotator cuff tear in mice

    PubMed Central

    Shirasawa, Hideyuki; Matsumura, Noboru; Shimoda, Masayuki; Oki, Satoshi; Yoda, Masaki; Tohmonda, Takahide; Kanai, Yae; Matsumoto, Morio; Nakamura, Masaya; Horiuchi, Keisuke

    2017-01-01

    Fatty infiltration in muscle is often observed in patients with sizable rotator cuff tear (RCT) and is thought to be an irreversible event that significantly compromises muscle plasticity and contraction strength. These changes in the mechanical properties of the affected muscle render surgical repair of RCT highly formidable. Therefore, it is important to learn more about the pathology of fatty infiltration to prevent this undesired condition. In the present study, we aimed to generate a mouse model that can reliably recapitulate some of the important characteristics of muscular fatty infiltration after RCT in humans. We found that fatty infiltration can be efficiently induced by a combination of the following procedures: denervation of the suprascapular nerve, transection of the rotator cuff tendon, and resection of the humeral head. Using this model, we found that platelet-derived growth factor receptor-α (PDGFRα)-positive mesenchymal stem cells are induced after this intervention and that inhibition of PDGFR signaling by imatinib treatment can significantly suppress fatty infiltration. Taken together, the present study presents a reliable fatty infiltration mouse model and suggests a key role for PDGFRα-positive mesenchymal stem cells in the process of fatty infiltration after RCT in humans. PMID:28139720

  14. A nonlinear constitutive model for stress relaxation in ligaments and tendons.

    PubMed

    Davis, Frances M; De Vita, Raffaella

    2012-12-01

    A novel constitutive model that describes stress relaxation in transversely isotropic soft collagenous tissues such as ligaments and tendons is presented. The model is formulated within the nonlinear integral representation framework proposed by Pipkin and Rogers (J. Mech. Phys. Solids. 16:59-72, 1968). It represents a departure from existing models in biomechanics since it describes not only the strain dependent stress relaxation behavior of collagenous tissues but also their finite strains and transverse isotropy. Axial stress-stretch data and stress relaxation data at different axial stretches are collected on rat tail tendon fascicles in order to compute the model parameters. Toward this end, the rat tail tendon fascicles are assumed to be incompressible and undergo an isochoric axisymmetric deformation. A comparison with the experimental data proves that, unlike the quasi-linear viscoelastic model (Fung, Biomechanics: Mechanics of Living Tissues. Springer, New York, 1993) the constitutive law can capture the observed nonlinearities in the stress relaxation response of rat tail tendon fascicles.

  15. Comparative biochemical analysis of sea urchin peristome and rat tail tendon collagen.

    PubMed

    Robinson, J J

    1997-06-01

    We report here a biochemical comparison between type 1 rat tail tendon collagen and collagen isolated from sea urchin peristome tissue. The sea urchin collagen consisted of two species of apparent mol masses, 140 and 116 kDa. Amino acid compositional analysis of the 140 and 116 kDa species revealed the presence of hydroxyproline and hydroxylysine as well as a glycine content of 28.1 mol.%. In solubility experiments the rat tail tendon collagen was found to precipitate at sodium chloride concentrations between 1 and 2 M while peristome collagen remained soluble at salt concentrations as high as 4 M. Incubation of the peristome and rat tail tendon collagen preparations with a sea urchin collagenase/gelatinase resulted in cleavage of the former but not the latter collagen. Upon heat denaturation at 60 degrees C, however, the rat tail tendon collagen served as a substrate for the gelatinase. Cyanogen bromide cleavage of rat tail and peristome collagens generated largely unique peptide maps. Collectively, these results suggest that structural differences exist between echinoderm and vertebrate type 1 collagens.

  16. Severe extensor tendon attrition and multiple tendon ruptures resulting from Kienböck's disease.

    PubMed

    Ramkumar, S; Josty, I C; Sykes, P J

    2000-12-01

    Kienböck's disease is a rare but recognized cause of chronic wrist pain. Occasionally, complications arise leading to tendon rupture. The authors present the first reported case of attrition to all extensors of the hand, and extensor tendon rupture to the little finger in a patient with a 45-year history of Kienböck's disease. This is also the first reported incidence of this complication in whites. Clinical features, surgical management, and the successful outcome are discussed.

  17. 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

  18. Muscle - tendon unit mechanical and morphological properties and sprint performance.

    PubMed

    Stafilidis, Savvas; Arampatzis, Adamantios

    2007-07-01

    The objective of this study was to determine whether sprint performance is related to the mechanical (elongation - force relationship of the tendon and aponeurosis, muscle strength) and morphological (fascicle length, pennation angle, muscle thickness) properties of the quadriceps femoris and triceps surae muscle - tendon units. Two groups of sprinters (slow, n = 11; fast, n = 17) performed maximal isometric knee extension and plantar flexion contractions on a dynamometer at 11 different muscle - tendon unit lengths. Elongation of the tendon and aponeurosis of the gastrocnemius medialis and the vastus lateralis was measured using ultrasonography. We observed no significant differences in maximal joint moments at the ankle and knee joints or morphological properties of the gastrocnemius medialis and vastus lateralis between groups (P > 0.05). The fast group exhibited greater elongation of the vastus lateralis tendon and aponeurosis at a given tendon force, and greater maximal elongation of the vastus lateralis tendon and aponeurosis during maximum voluntary contraction (P < 0.05). Furthermore, maximal elongation of the vastus lateralis tendon and aponeurosis showed a significant correlation with 100-m sprint times (r = -0.567, P = 0.003). For the elongation - force relationship at the gastrocnemius medialis tendon and aponeurosis, the two groups recorded similar values. It is suggested that the greater elongation of the vastus lateralis tendon and aponeurosis of the fast group benefits energy storage and return as well as the shortening velocity of the muscle - tendon unit.

  19. Abductor pollicis longus tendon division with swan neck thumb deformity.

    PubMed

    Zacharia, Balaji; Puthezhath, Kishore

    2012-08-01

    Swan neck thumb deformity can be caused by osteoarthritis, rheumatoid arthritis, systemic lupus erythematosus, tendon transfers and paralytic diseases. Abductor pollicis longus is one of the major stabilizing tendon of the carpometacarpal joint of thumb. To the best of our knowledge, swan neck thumb deformity owing to division of abductor pollicis longus tendon is rare. In this article, we describe a case of isolated division of abductor pollicis longus tendon presenting with swan-neck deformity of thumb and discuss the mechanism, management and outcome. The patient was treated by repair of the divided tendon using palmaris longus tendon graft. At approximately 107 weeks following treatment, the patient was having full range of thumb movement and the deformity completely disappeared. We also describe the unusual mechanism whereby an isolated division of abductor pollicis longus tendon results in swan neck thumb deformity. Level of clinical evidence IV.

  20. [Flexor tendon pulley system: anatomy, pathology, treatment].

    PubMed

    Moutet, F

    2003-02-01

    Flexor tendon pulley has been very early noticed and described. Terminology usually accepted recognizes 6 arcifom pulleys (A0 to A5) and 3 cruciform pulleys (C1 to C3). Anatomy and physiology of this flexor tendon gliding and reflection system at the level of the digital sheet are exposed. The integrity necessity of this system became obvious regarding the flexor tendons repair. Four main pathologies may be concerned: the trigger finger congenital or progressive, due to a chondroid metaplasia of the A1 pulley; tenosynovial ganglions arising at the weak point between A1 and A2 pulley; lesions of the flexor tendon sheet during traumatic lacerations or surgical repairs; quite experimental lesions creating isolated ruptures of one or several pulleys which occur during sport practice, especially high level rock climbing. The repair techniques are exposed to allow to graduate and hierarchy the reparation technique regarding the pathology. A2 and A4 repair is always indicated. The best reconstruction material is an extensor retinaculum graft. But its poor surface available often draws to use conventional palmaris longus free graft.

  1. The acoustoelastic effect in prestressing tendons

    NASA Astrophysics Data System (ADS)

    Washer, Glenn Alden

    There are currently more than 130,000 prestressed concrete bridges in the United States and approximately 37,000 of these bridges are more than 30 years old. Steel tendons that are pre-tensioned to counteract the effect of design loads are critical to structural performance of these bridges. However, there are currently no accepted nondestructive evaluation techniques to evaluate the condition of these tendons. The goal of this research was to examine ultrasonic stress measurement techniques for the condition assessment of prestressing tendons. Acoustoelastic measurements were made in prestressing rods and strands, and constants are reported that relate the change in ultrasonic velocity to the change in stress. The effects of dispersion in prestressing tendons, which act as circular wave guides for ultrasonic waves, are evaluated. Factors that could effect the design of a practical sensor are examined, including temperature dependence, effect of varying boundary conditions, and the variation in acoustoelastic properties between typical materials produced by different manufacturers. It is concluded that several of these factors have a larger effect on the ultrasonic velocities than stress. Therefore, it may be impractical to design a sensor system to measure absolute stress, but measurement of stress changes from a known initial condition may be possible under certain circumstances.

  2. Mouse models in tendon and ligament research.

    PubMed

    Mienaltowski, Michael J; Birk, David E

    2014-01-01

    Mutant mouse models are valuable resources for the study of tendon and ligament biology. Many mutant mouse models are used because their manifested phenotypes mimic clinical pathobiology for several heritable disorders, such as Ehlers-Danlos Syndrome and Osteogenesis Imperfecta. Moreover, these models are helpful for discerning roles of specific genes in the development, maturation, and repair of musculoskeletal tissues. There are several categories of genes with essential roles in the synthesis and maintenance of tendon and ligament structures. The form and function of these tissues depend highly upon fibril-forming collagens, the primary extracellular macromolecules of tendons and ligaments. Models for these fibril-forming collagens, as well as for regulatory molecules like FACITs and SLRPs, are important for studying fibril assembly, growth, and maturation. Additionally, mouse models for growth factors and transcription factors are useful for defining regulation of cell proliferation, cell differentiation, and cues that stimulate matrix synthesis. Models for membrane-bound proteins assess the roles of cell-cell communication and cell-matrix interaction. In some cases, special considerations need to be given to spatio-temporal control of a gene in a model. Thus, conditional and inducible mouse models allow for specific regulation of genes of interest. Advances in mouse models have provided valuable tools for gaining insight into the form and function of tendons and ligaments.

  3. Tear production in three captive wild herbivores in Israel.

    PubMed

    Ofri, R; Horowitz, I; Kass, P H

    1999-01-01

    The Schirmer tear test (STT) I was performed to evaluate tear production in 12 captive Nubian ibex (Capra ibex nubiana), 10 captive Burchell's zebras (Equus burchelli) and five Arabian oryx (Oryx leucoryx) at the Tel-Aviv Ramat-Gan Zoological Center (Israel). Mean (+/- standard deviation) STT values were 13.2 +/- 5.1 mm/min in the ibex, 23.4 +/- 3.4 mm/min in the zebra and 12.7 +/- 4.8 mm/min in the oryx. There were no significant effects of gender, age, weight, or side of the eye. There were no significant differences in STT values between ibex and oryx, but tear production in both species was significantly lower than in zebras. Knowledge of normal tear production values is important for the differential diagnosis of conjunctivitis and keratitis in these species.

  4. Contact lens and tear film dynamics during blinking

    NASA Astrophysics Data System (ADS)

    Reid, Timothy; Anderson, Daniel

    2016-11-01

    We develop a mathematical model that couples the dynamics of the tear film and contact lens during blinking. We derive an ordinary differential equation for the motion of the contact lens (parallel to the cornea) driven and retarded by viscous forces in the thin fluid films separating the contact lens from the eyelids and the corneal surface. Using the contact lens motion and tear film dynamics models we calculate a numerical solution of tear film thickness, showing that the lens and lid motion influence the tear film dynamics. The numerical solution uses a mapped Chebyshev spectral method for the spatial derivatives to reduce the model to a system of differential algebraic equations. National Science Foundation Grants (DMS-1407087) and (DMS-1107848).

  5. Nonlinear tearing modes stabilization by oscillating the resonant surface

    NASA Astrophysics Data System (ADS)

    Yang, Xiaoqing; Wang, Shaojie

    2016-09-01

    The stabilization of the nonlinear tearing mode by rapidly oscillating the resonant surface has been investigated numerically in a large aspect ratio tokamak with a circular cross-section. By means of the radio frequency current drive, the plasma current can be modulated to make the resonant surface (rs) oscillate in time near its mean position. Previous results show that the linear tearing mode can be suppressed by oscillating the resonant surface with a suitable frequency and amplitude. At the nonlinear stage, the tearing mode stabilization shows different properties. The suppression effects not only depend on the modulation frequency and the oscillation width of the resonant surface but also depend on the relative size of χ0 to δ (here, χ0 is the oscillation width of the resonant surface and δ is the width of tearing layer) and the relative width of χ0 to the magnetic island width W.

  6. Tears of wine: new insights on an old phenomenon

    PubMed Central

    Venerus, David C.; Nieto Simavilla, David

    2015-01-01

    Anyone who has enjoyed a glass of wine has undoubtedly noticed the regular pattern of liquid beads that fall along the inside of the glass, or ‘tears of wine.’ The phenomenon is the result of a flow against gravity along the liquid film on the glass, which is induced by an interfacial tension gradient. It is generally accepted that the interfacial tension gradient is due to a composition gradient resulting from the evaporation of ethanol. We re-examine the tears of wine phenomenon and investigate the importance of thermal effects, which previously have been ignored. Using a novel experiment and simple model we find that evaporative cooling contributes significantly to the flow responsible for wine tears, and that this phenomenon occurs primarily because of the thermodynamic behavior of ethanol-water mixtures. Also, the regular pattern of tear formation is identified as a well-known hydrodynamic instability. PMID:26548566

  7. Tears of wine: new insights on an old phenomenon

    NASA Astrophysics Data System (ADS)

    Venerus, David C.; Nieto Simavilla, David

    2015-11-01

    Anyone who has enjoyed a glass of wine has undoubtedly noticed the regular pattern of liquid beads that fall along the inside of the glass, or ‘tears of wine.’ The phenomenon is the result of a flow against gravity along the liquid film on the glass, which is induced by an interfacial tension gradient. It is generally accepted that the interfacial tension gradient is due to a composition gradient resulting from the evaporation of ethanol. We re-examine the tears of wine phenomenon and investigate the importance of thermal effects, which previously have been ignored. Using a novel experiment and simple model we find that evaporative cooling contributes significantly to the flow responsible for wine tears, and that this phenomenon occurs primarily because of the thermodynamic behavior of ethanol-water mixtures. Also, the regular pattern of tear formation is identified as a well-known hydrodynamic instability.

  8. 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.

  9. Tear osmolarity and dry eye symptoms in diabetics

    PubMed Central

    Fuerst, Nicole; Langelier, Nicole; Massaro-Giordano, Mina; Pistilli, Maxwell; Stasi, Kalliopi; Burns, Carrie; Cardillo, Serena; Bunya, Vatinee Y

    2014-01-01

    Purpose To assess the relationship between tear osmolarity and dry eye symptoms in patients with diabetes. Patients and methods Fifty patients with diabetes were enrolled. Demographic information and past medical history were recorded. Symptoms were assessed using the ocular surface disease index (OSDI). Tear osmolarity of each eye was measured with the TearLab® Osmolarity System. Results The majority of the subjects were female (76%), African American (56%), and/or had a diagnosis of type 2 diabetes (82%). The mean ± standard deviation (SD) for age was 54.6±13.4, and maximum tear osmolarity was 304.6±12.7 mOsm/L. Men had higher osmolarity than women (mean ± standard error (SE) 311.8±4.0 mOsm/L versus 302.3±1.9 mOsm/L, P=0.02). Age, race, use of artificial tears, years of diabetes, and hemoglobin A1c did not have a statistically significant association with tear osmolarity. Longer duration of diabetes was associated with lower (less severe) OSDI scores (r=−0.35, P=0.01). Higher tear osmolarity was associated with lower (less severe) OSDI scores (r=−0.29, P=0.04). Conclusion Approximately half of the diabetic subjects in our study had elevated tear osmolarity, and half of our population also reported symptoms consistent with dry eye disease. However, the two were slightly inversely related in that those with higher osmolarity reported fewer symptoms. Subjects with a longer duration of diabetes also reported fewer dry eye symptoms. Therefore, health care providers should be aware that patients who are most likely to have ocular surface disease, including those with long-standing diabetes, may not experience symptoms and seek care in a timely manner. PMID:24648714

  10. Linear tearing modes in an electron-positron plasma

    NASA Astrophysics Data System (ADS)

    Guiliang, SONG; Huishan, CAI

    2017-04-01

    The general dispersion of tearing modes due to the effects of electron inertia and resistivity in pair plasmas is derived analytically, and is discussed in two cases: \\bigtriangleup \\prime \\gg 1 and \\bigtriangleup \\prime \\ll 1, where {{Δ }}\\prime is the instability criterion of the tearing mode. It is found that the conditions under which either resistivity or electron inertia dominates depend strongly on the limit of {{Δ }}\\prime considered.

  11. The severe acute respiratory syndrome coronavirus in tears

    PubMed Central

    Loon, S-C; Teoh, S C B; Oon, L L E; Se-Thoe, S-Y; Ling, A-E; Leo, Y-S; Leong, H-N

    2004-01-01

    Background: Severe acute respiratory syndrome (SARS) is a new infectious disease that caused a global outbreak in 2003. Research has shown that it is caused by a novel coronavirus. A series of cases is reported where polymerase chain reaction (PCR) testing on tears had demonstrated the presence of the virus. Detection of ocular infection from tears using the PCR technique has been widely used by ophthalmologists to diagnose infections for other viruses. Methods: This is a case series report from cases classified as probable or suspect SARS cases. Tear samples were collected from 36 consecutive patients who were suspected of having SARS in Singapore over a period of 12 days (7–18 April 2003), and analysed by PCR using protocols developed by the WHO network of laboratories. Results: Three patients with probable SARS (one female and two male patients) had positive results from their tear samples. Tear samples were used to confirm SARS in the female patient, who was positive only from her tears. The positive specimens were found in cases sampled early in their course of infection. Conclusions: This is the first case series reported with the detection of the SARS coronavirus from tears, and has important implications for the practice of ophthalmology and medicine. The ability to detect and isolate the virus in the early phase of the disease may be an important diagnostic tool for future patients and tear sampling is both simple and easily repeatable. Many healthcare workers are in close proximity to the eyes of patients and this may be a source of spread among healthcare workers and inoculating patients. Ophthalmic practices may need to change as more stringent barrier methods, appropriate quarantine, and isolation measures are vital when managing patients with SARS. PMID:15205225

  12. Dynamics of goat distal hind limb muscle–tendon function in response to locomotor grade

    PubMed Central

    McGuigan, M. Polly; Yoo, Edwin; Lee, David V.; Biewener, Andrew A.

    2009-01-01

    Summary The functional roles of the lateral gastrocnemius (LG), medial gastrocnemius (MG) and superficial digital flexor (SDF) muscle–tendon units (MTUs) in domestic goats (N=6) were studied as a function of locomotor grade, testing the hypothesis that changes in distal limb muscle work would reflect changes in mechanical work requirements while goats walked or trotted on the level, 15 deg. decline and 15 deg. incline. As steep terrain-adapted animals, changes in muscle work output are expected to be particularly important for goats. In vivo muscle–tendon forces, fascicle length changes and muscle activation were recorded via tendon force buckles, sonomicrometry and electromyography to evaluate the work performance and elastic energy recovery of the three distal MTUs. These recordings confirmed that fascicle strain and force within goat distal hind limb muscles are adjusted in response to changes in mechanical work demand associated with locomotor grade. In general, muscle work was modulated most consistently by changes in fascicle strain, with increased net shortening (P<0.001) observed as goats switched from decline to level to incline locomotion. Peak muscle stresses increased as goats increased speed from a walk to a trot within each grade condition (P<0.05), and also increased significantly with grade (P<0.05 to P<0.01). Due to the increase in net fascicle shortening and muscle force, net muscle work per cycle also increased significantly (P<0.05 to P<0.005) as goats switched from decline to level to incline conditions (LG work: 20 mJ to 56 mJ to 209 mJ; MG work: –7 mJ to 34 mJ to 179 mJ; SDF work: –42 mJ to 14 mJ to 71 mJ, at a 2.5 ms–1 trot). Although muscle work was modulated in response to changes in grade, the amount of work produced by these three distal pennate muscles was small (being <3%) in comparison with the change in mechanical energy required of the limb as a whole. Elastic energy recovery in the SDF and gastrocnemius (GA) tendons was

  13. 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

  14. Retinal tear: an unusual complication of ocular toxoplasmosis

    PubMed Central

    Celebi, Ali Riza Cenk; Kilavuzoglu, Ayse Ebru; Altiparmak, Ugur Emrah; Cosar, Cemile Banu; Ozkiris, Abdullah

    2015-01-01

    Purpose It is aimed to report on a 16-year-old patient with acquired ocular toxoplasmosis complicated by a retinal tear. Methods Retrospective medical chart review Results A 16-year-old Caucasian female presented with vision loss in her right eye. In addition to a white active lesion between the fovea and the optic nerve head, marked vitreous opacification was noted. She was diagnosed with ocular toxoplasmosis. The patient was treated with oral azithromycin, clindamycin, and trimethoprimsulfamethoxazole. One month later, retinochoroiditis resolved and vitreous cleared. Three months after onset, patient presented with floaters in the right eye and a retinal tear was located at the temporal region of the retina. Prophylactic argon laser treatment that encircled the retinal tear was performed. No other abnormalities were noted during 6 months of follow-up. Conclusions Retinal tear associated with ocular toxoplasmosis is rare; however, a retinal tear can occur due to vitreoretinal traction following post-inflammatory structural alteration of the vitreous. Retinal tears may be seen during the healing phase, when the inflammation turns into tightening of vitreous substance. Careful retinal examination in cases of ocular toxoplasmosis is warranted, especially in patients with severe vitreous inflammation. PMID:28352754

  15. [Potential for use of hydroxypropyl guar in tear substitute therapy].

    PubMed

    Brzhesky, V V; Golubev, S Yu

    2017-01-01

    Of the large number of polymers used in artificial tear formulations, natural polysaccharides - hydroxypropyl guar, sodium hyaluronate, chondroitin sulfate, dextran, etc., are gaining more and more popularity. Hydroxypropyl guar stands out through its ability to form a long-lasting structured matrix adhered to the damaged ocular surface and ensuring good wettability of the latter and regeneration of epithelial cells. At that, the viscosity of hydroxypropyl guar increases with increasing tear pH (which, in turn, correlates with the severity of xerosis) and further prolongs the moisturizing effect. According to experimental studies, the in vitro protective activity of hydroxypropyl guar surpasses that of sodium hyaluronate, which is widely used. Thus, corneal epithelial cell cultures were more tolerant to drying and pericardial leaflets showed lower friction coefficient, if pretreated with hydroxypropyl guar and not hyaluronic acid. Subsequent clinical studies showed that Systane Ultra was more effective in patients with dry eye syndrome than a carboxymethylcellulose and glycerol-containing drug. It has been also proved that Systane Balance provides a greater increase in thickness of the tear film lipid layer and in overall stability of the tear film as compared to SootheXP, which has a similar lipid composition. The present review also covers potential utility of other artificial tear formulations that, besides the moisturizing effect, are able to reduce the tear film osmolarity, prevent further oxidative stress, and abate the inflammatory process.

  16. Anatomic variation of the 5th extensor tendon compartment and extensor digiti minimi tendon.

    PubMed

    Tanaka, Toshikazu; Moran, Steven L; Zhao, Chunfeng; Zobitz, Mark E; An, Kai-Nan; Amadio, Peter C

    2007-08-01

    Anatomic variation within the 5th extensor compartment may contribute to the development of tenosynovitis and limit the usefulness of the extensor digiti minimi (EDM) for tendon transfer. The purpose of this study was to assess the anatomic variation of the EDM tendon and its surrounding retinaculum, with particular attention to anatomical variation between specimens. Forty-one fresh cadaver hands were dissected. The length of the 5th compartment retinaculum was noted. The incidence of an intercompartmental septum was noted in each specimen as well as the type of tendinous attachments present between the EDM and extensor digitorum communis (EDC) tendons. The presence and length of any accessory retinacular bands distal to the edge of proper extensor retinaculum was also noted. Only one specimen contained a single EDM tendon, while 71% (n = 29) of specimens contained two slips and 23% (n = 9) had three slips; 24% (n = 10) of EDC tendons had no slip to the small finger, while 61% (n = 25) of specimens had a single slip to the small finger. The EDC's contribution to the small finger was found to be an independent tendon in 42% of cases (n = 17), while 34% (n = 14) of specimens were found to have a common EDC slip, which branched to both the ring and small finger. Three EDM tendons divided distal to the extensor retinaculum, while the remaining EDM tendons divided beneath or proximal to the extensor retinaculum. Seventy-three percent (n = 30) of the specimens had an accessory retinacular band surrounding the EDM tendon identified at the base of the 5th metacarpal. Eighty-eight percent (n = 36) of hands had a septum between the EDM slips. The surgeon should be aware of variability within the 5th dorsal compartment in cases of trauma and in cases of tendon transfer. In our series 30 of 41 specimens were noted to contain an accessory dorsal retinacular band surrounding the EDM and 36 specimens were noted to contain a septum within the 5th compartment. The presence of an

  17. Collisionless tearing instability of a bi-Maxwellian neutral sheet - An integrodifferential treatment with exact particle orbits

    NASA Technical Reports Server (NTRS)

    Burkhart, G. R.; Chen, J.

    1989-01-01

    The integrodifferential equation describing the linear tearing instability in the bi-Maxwellian neutral sheet is solved without approximating the particle orbits or the eigenfunction psi. Results of this calculation are presented. Comparison between the exact solution and the three-region approximation motivates the piecewise-straight-line approximation, a simplification that allows faster solution of the integrodifferential equation, yet retains the important features of the exact solution.

  18. In Vivo Evaluation of Adipose-Derived Stromal Cells Delivered with a Nanofiber Scaffold for Tendon-to-Bone Repair

    PubMed Central

    Lipner, Justin; Shen, Hua; Cavinatto, Leonardo; Liu, Wenying; Havlioglu, Necat; Xia, Younan; Galatz, Leesa M.

    2015-01-01

    Rotator cuff tears are common and cause a great deal of lost productivity, pain, and disability. Tears are typically repaired by suturing the tendon back to its bony attachment. Unfortunately, the structural (e.g., aligned collagen) and compositional (e.g., a gradient in mineral) elements that produce a robust attachment in the healthy tissue are not regenerated during healing, and the repair is prone to failure. Two features of the failed healing response are deposition of poorly aligned scar tissue and loss of bone at the repair site. Therefore, the objective of the current study was to improve tendon-to-bone healing by promoting aligned collagen deposition and increased bone formation using a biomimetic scaffold seeded with pluripotent cells. An aligned nanofibrous poly(lactic-co-glycolic acid) scaffold with a gradient in mineral content was seeded with adipose-derived stromal cells (ASCs) and implanted at the repair site of a rat rotator cuff model. In one group, cells were transduced with the osteogenic factor bone morphogenetic protein 2 (BMP2). The healing response was examined in four groups (suture only, acellular scaffold, cellular scaffold, and cellular BMP2 scaffold) using histologic, bone morphology, and biomechanical outcomes at 14, 28, and 56 days. Histologically, the healing interface was dominated by a fibrovascular scar response in all groups. The acellular scaffold group showed a delayed healing response compared to the other groups. When examining bone morphology parameters, bone loss was evident in the cellular BMP2 group compared to other groups at 28 days. When examining repair-site mechanical properties, strength and modulus were decreased in the cellular BMP2 groups compared to other groups at 28 and 56 days. These results indicated that tendon-to-bone healing in this animal model was dominated by scar formation, preventing any positive effects of the implanted biomimetic scaffold. Furthermore, cells transduced with the osteogenic factor

  19. Tearing Mode Stability of Evolving Toroidal Equilibria

    NASA Astrophysics Data System (ADS)

    Pletzer, A.; McCune, D.; Manickam, J.; Jardin, S. C.

    2000-10-01

    There are a number of toroidal equilibrium (such as JSOLVER, ESC, EFIT, and VMEC) and transport codes (such as TRANSP, BALDUR, and TSC) in our community that utilize differing equilibrium representations. There are also many heating and current drive (LSC and TORRAY), and stability (PEST1-3, GATO, NOVA, MARS, DCON, M3D) codes that require this equilibrium information. In an effort to provide seamless compatibility between the codes that produce and need these equilibria, we have developed two Fortran 90 modules, MEQ and XPLASMA, that serve as common interfaces between these two classes of codes. XPLASMA provides a common equilibrium representation for the heating and current drive applications while MEQ provides common equilibrium and associated metric information needed by MHD stability codes. We illustrate the utility of this approach by presenting results of PEST-3 tearing stability calculations of an NSTX discharge performed on profiles provided by the TRANSP code. Using the MEQ module, the TRANSP equilibrium data are stored in a Fortran 90 derived type and passed to PEST3 as a subroutine argument. All calculations are performed on the fly, as the profiles evolve.

  20. Meniscus tear surgery and meniscus replacement

    PubMed Central

    Vaquero, Javier; Forriol, Francisco

    2016-01-01

    Summary Objective the menisci are easily injured and difficult to repair. The aim of this study was to analyze the current state of meniscal surgery aimed at preserving morphology and conserving the biomechanics of the knee to prevent joint degeneration. Methodology a search of the electronic medical literature database Medline was conducted, from http://www.ncbi.nlm.nih.gov/pubmed. The search was not limited by language. Candidate articles were identified by searching for those that included the keywords meniscus, surgery, suture, implant, allograft. The limits were included for clinical research and clinical trials. Basic research was not included. The studies selected were evaluated and classified in three different categories: basic science, reconstruction (suture and meniscectomy) and implants (scaffolds and allograft). Results the consequences of meniscectomy performed at a young age can lead to a joint cartilage degeneration twenty years later. There are few surgical options for the repair of meniscal injuries in order both to preserve the meniscus and to ensure the long term survival of the knee joint, meniscectomy, repair, suturing the tear, or reconstruction, when a meniscal allograft or synthetic substitute is used to replace the meniscus, but the biomechanical properties of the native meniscus are not reproduced entirely by the scaffolds that exist today. Conclusion therapies that successfully repair or replace the meniscus are therefore likely to prevent or delay osteoarthritis progression. PMID:27331034

  1. STRESS CORROSION CRACKING IN TEAR DROP SPECIMENS

    SciTech Connect

    Lam, P; Philip Zapp, P; Jonathan Duffey, J; Kerry Dunn, K

    2009-05-01

    Laboratory tests were conducted to investigate the stress corrosion cracking (SCC) of 304L stainless steel used to construct the containment vessels for the storage of plutonium-bearing materials. The tear drop corrosion specimens each with an autogenous weld in the center were placed in contact with moist plutonium oxide and chloride salt mixtures. Cracking was found in two of the specimens in the heat affected zone (HAZ) at the apex area. Finite element analysis was performed to simulate the specimen fabrication for determining the internal stress which caused SCC to occur. It was found that the tensile stress at the crack initiation site was about 30% lower than the highest stress which had been shifted to the shoulders of the specimen due to the specimen fabrication process. This finding appears to indicate that the SCC initiation took place in favor of the possibly weaker weld/base metal interface at a sufficiently high level of background stress. The base material, even subject to a higher tensile stress, was not cracked. The relieving of tensile stress due to SCC initiation and growth in the HAZ and the weld might have foreclosed the potential for cracking at the specimen shoulders where higher stress was found.

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

    PubMed

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

    2010-06-01

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

  3. 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

  4. Flexor tendon injuries. Part 5. Flexor tenolysis, rehabilitation and results.

    PubMed

    Strickland, J W

    1987-03-01

    In this five-part series, we have attempted to review our current understanding of flexor tendon anatomy, physiology, biomechanics, healing and adhesion formation around a repaired tendon. The methods of acute flexor tendon repair, conventional free tendon grafting, staged flexor tendon reconstruction and pulley restoration have been discussed as well as flexor tenolysis, rehabilitation and results. From these articles it may be seen that flexor tendon surgery is a complex and difficult art which requires a thorough appreciation of the normal flexor tendon system, the exact status of that system following injury and a strong understanding of the techniques which may be best utilized to restore flexor tendon function. The procedures described require both technical skill and experience and postoperative therapy programs must be carefully instituted based on the unique status of each patient. With the important advances occurring in many areas of flexor tendon surgery, it is realistic to believe that in the near future the techniques described in these articles may be substantially altered and modified. Results will continue to improve until the patient and surgeon can realistically expect to return most digits to nearly full function after flexor tendon interruption.

  5. The Cellular Biology of Flexor Tendon Adhesion Formation

    PubMed Central

    Wong, Jason K.F.; Lui, Yin H.; Kapacee, Zoher; Kadler, Karl E.; Ferguson, Mark W. J.; McGrouther, Duncan A.

    2009-01-01

    Intrasynovial flexor tendon injuries of the hand can frequently be complicated by tendon adhesions to the surrounding sheath, limiting finger function. We have developed a new tendon injury model in the mouse to investigate the three-dimensional cellular biology of intrasynovial flexor tendon healing and adhesion formation. We investigated the cell biology using markers for inflammation, proliferation, collagen synthesis, apoptosis, and vascularization/myofibroblasts. Quantitative immunohistochemical image analysis and three-dimensional reconstruction with cell mapping was performed on labeled serial sections. Flexor tendon adhesions were also assessed 21 days after wounding using transmission electron microscopy to examine the cell phenotypes in the wound. When the tendon has been immobilized, the mouse can form tendon adhesions in the flexor tendon sheath. The cell biology of tendon healing follows the classic wound healing response of inflammation, proliferation, synthesis, and apoptosis, but the greater activity occurs in the surrounding tissue. Cells that have multiple “fibripositors” and cells with cytoplasmic protrusions that contain multiple large and small diameter fibrils can be found in the wound during collagen synthesis. In conclusion, adhesion formation occurs due to scarring between two damaged surfaces. The mouse model for flexor tendon injury represents a new platform to study adhesion formation that is genetically tractable. PMID:19834058

  6. 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

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

    PubMed Central

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

    2015-01-01

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

  8. Afferents contributing to autogenic inhibition of gastrocnemius following electrical stimulation of its tendon.

    PubMed

    Khan, Serajul I; Burne, John A

    2009-07-28

    Electrical stimulation of the Achilles tendon produced strong reflex inhibition of the ongoing voluntary EMG activity in the two heads of the gastrocnemius (GA) muscle in all tested subjects. The inhibition was seen clearly in both averaged and single sweep surface EMG records. The inhibitory response was produced without electrical (M wave) or mechanical, (muscle twitch) signs of direct muscle stimulation. The onset latency and duration for the first period of inhibition (I(1)) were 47-49 ms and 67 ms, respectively. A second inhibition (I(2)) had an onset latency of 187-193 ms and duration under 40 ms. Non-noxious stimuli in the range of 2.6-7.6 x mean perceptual threshold, when delivered to four locations over the GA tendon, all produced clear inhibition of the voluntary muscle activity. The inhibition was maximal when the cathode was a large metal plate located near the musculotendinous junction and decreased approximately linearly with distances more distal to that site. The effect of passive muscle stretch on the electrically induced tendon reflex inhibition (TRE) was tested at ankle joint angles incremented in steps of 20 degrees. It was found that TRE is strongly dependent on joint angle, being maximal in the fully stretched muscle. TRE was lost completely after partial tibial nerve block. In comparison, GA inhibition produced by cutaneous (sural) nerve stimulation was of a higher threshold, longer latency and persisted after partial tibial nerve block. We thus demonstrated a powerful autogenic inhibition in the lower limb arising from tendon afferents in conscious subjects that is increased by passive muscle stretch and likely to originate from group I tendon afferents.

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

    PubMed

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

    2015-04-15

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

  11. 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.

  12. 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

  13. 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.

  14. Fetal development of the pulley for muscle insertion tendons: A review and new findings related to the tensor tympani tendon.

    PubMed

    Rodríguez-Vázquez, Jose Francisco; Honkura, Yohei; Katori, Yukio; Murakami, Gen; Abe, Hiroshi

    2017-01-01

    The existence of hard tissue pulleys that act to change the direction of a muscle insertion tendon is well known in the human body. These include (1) the trochlea for the extraocular obliquus superior muscle, (2) the pterygoid hamulus for the tensor veli palatini muscle, (3) the deep sulcus on the plantar aspect of the cuboid bone for the peroneus longus tendon, (4) the lesser sciatic notch for the obturator internus muscle, and (5) the bony trochleariformis process for the tensor tympani muscle tendon. In addition, (6) the stapedius muscle tendon shows a lesser or greater angulation at the pyramidal eminence of the temporal bone. Our recent studies have shown that the development of pulleys Nos. 1 and 2 can be explained by a change in the topographical relationship between the pulley and the tendon, that of pulley No. 3 by the rapidly growing calcaneus pushing the tendon, and that of pulley No. 4 by migration of the insertion along the sciatic nerve and gluteus medius tendon. Therefore, in Nos. 1-4, an initially direct tendon curves secondarily and obtains an attachment to the pulley. In case No. 6, the terminal part of the stapedius tendon originates secondarily from the interzone mesenchymal tissue of the incudostapedial joint. In the case of pulley No. 5, we newly demonstrated that its initial phase of development was similar to No. 6, but the tensor tympani tendon achieved a right-angled turn under guidance by a specific fibrous tissue and it migrated along the growing malleus manubrium.

  15. LRT, a tendon-specific leucine-rich repeat protein, promotes muscle-tendon targeting through its interaction with Robo.

    PubMed

    Wayburn, Bess; Volk, Talila

    2009-11-01

    Correct muscle migration towards tendon cells, and the adhesion of these two cell types, form the basis for contractile tissue assembly in the Drosophila embryo. While molecules promoting the attraction of muscles towards tendon cells have been described, signals involved in the arrest of muscle migration following the arrival of myotubes at their corresponding tendon cells have yet to be elucidated. Here, we describe a novel tendon-specific transmembrane protein, which we named LRT due to the presence of a leucine-rich repeat domain (LRR) in its extracellular region. Our analysis suggests that LRT acts non-autonomously to better target the muscle and/or arrest its migration upon arrival at its corresponding tendon cell. Muscles in embryos lacking LRT exhibited continuous formation of membrane extensions despite arrival at their corresponding tendon cells, and a partial failure of muscles to target their correct tendon cells. In addition, overexpression of LRT in tendon cells often stalled muscles located close to the tendon cells. LRT formed a protein complex with Robo, and we detected a functional genetic interaction between Robo and LRT at the level of muscle migration behavior. Taken together, our data suggest a novel mechanism by which muscles are targeted towards tendon cells as a result of LRT-Robo interactions. This mechanism may apply to the Robo-dependent migration of a wide variety of cell types.

  16. 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.

  17. Relationships among Tear Film Stability, Osmolarity, and Dryness Symptoms

    PubMed Central

    Yeh, Thao N.; Graham, Andrew D.; Lin, Meng C.

    2016-01-01

    Purpose To examine the relationships among tear osmolarity, tear film stability, and several measures of dry eye (DE) symptoms in a multivariable analysis. Methods A cross-sectional study was conducted with 137 subjects (68 non–contact lens [CL] wearers and 69 soft CL wearers) recruited from a university campus. Tear breakup time (TBUT) was measured noninvasively (NITBUT) and with fluorescein (FTBUT). Tear osmolarity was measured by an osmometer. Dry eye symptoms were assessed using the Dry Eye Flow Chart and several different questionnaires. Results Subjects ranged in age from 18 to 67 years, with a mean of 28 years. Subjects had a mean (SD) osmolarity of 293 (10) mOsm/L, NITBUT of 14.1 (10.9) seconds, and FTBUT of 14.8 (12.6) seconds. Shorter NITBUT and FTBUT were significantly associated with female sex (p = 0.001 and p = 0.027, respectively) and Asian ethnicity (p = 0.030 and p = 0.004, respectively). There were no clinically significant relationships between tear osmolarity and FTBUT, NITBUT, or DE symptoms. Higher Dry Eye Flow Chart score (i.e., worse symptoms) was associated with older age (p < 0.001), female sex (p = 0.014), CL wear (p < 0.001), shorter NITBUT (p < 0.001), and shorter FTBUT (p = 0.028). The sensitivities and specificities for using clinical measurements to diagnose moderate to severe DE were as follows: osmolarity, 0.67 and 0.46, respectively; NITBUT, 0.72 and 0.52, respectively; and FTBUT, 0.68 and 0.57, respectively. Conclusions In a population of asymptomatic, mild and moderate DE patients, increased tear osmolarity was not significantly associated with reported symptom severity and frequency. Tear osmolarity, NITBUT, and FTBUT exhibited similar sensitivities and specificities when used to diagnose moderate to severe DE. PMID:26154693

  18. Bifurcated intraarticular long head of biceps tendon

    PubMed Central

    Pandey, Vivek; van Laarhoven, Simon Nurettin; Arora, Gaurav; Rao, Sripathi

    2014-01-01

    Though rare, many anomalous origins of long head of the biceps tendon (LHBT) have been reported in the literature. Anatomic variations commonly explained are a third humeral head, anomalous insertion, congenital absence and adherence to the rotator cuff. We report a rare case who underwent shoulder arthroscopy with impingement symptoms where in LHBT was found to be bifurcated with a part attached to superior labrum and the other part to the posterior capsule of joint. Furthermore, intraarticular portion of LHBT was adherent to the undersurface of the supraspinatus tendon. Awareness of such an anatomical aberration during the shoulder arthroscopy is of great importance as it can potentially avoid unnecessary confusion and surgery. PMID:25143652

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

    PubMed

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

    2011-01-01

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

  20. 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.

  1. Surgical Management of Fractures and Tendons.

    PubMed

    Pentecost, Rebecca; Niehaus, Andrew J; Anderson, David E

    2016-11-01

    Long bone fractures and disorders of tendons and ligaments represent a significant proportion