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Sample records for partial-thickness supraspinatus tendon

  1. Effect of partial-thickness tear on loading capacities of the supraspinatus tendon: a finite element analysis.

    PubMed

    Engelhardt, Christoph; Ingram, David; Müllhaupt, Philippe; Farron, Alain; Becce, Fabio; Pioletti, Dominique; Terrier, Alexandre

    2016-06-01

    Partial-thickness tears of the supraspinatus tendon frequently occur at its insertion on the greater tubercule of the humerus, causing pain and reduced strength and range of motion. The goal of this work was to quantify the loss of loading capacity due to tendon tears at the insertion area. A finite element model of the supraspinatus tendon was developed using in vivo magnetic resonance images data. The tendon was represented by an anisotropic hyperelastic constitutive law identified with experimental measurements. A failure criterion was proposed and calibrated with experimental data. A partial-thickness tear was gradually increased, starting from the deep articular-sided fibres. For different values of tendon tear thickness, the tendon was mechanically loaded up to failure. The numerical model predicted a loss in loading capacity of the tendon as the tear thickness progressed. Tendon failure was more likely when the tendon tear exceeded 20%. The predictions of the model were consistent with experimental studies. Partial-thickness tears below 40% tear are sufficiently stable to persist physiotherapeutic exercises. Above 60% tear surgery should be considered to restore shoulder strength. PMID:26290956

  2. Effect of Supraspinatus Tendon Injury on Supraspinatus and Infraspinatus Muscle Passive Tension and Associated Biochemistry

    PubMed Central

    Silldorff, Morgan D.; Choo, Alexander D.; Choi, Anthony J.; Lin, Evie; Carr, J. Austin; Lieber, Richard L.; Lane, John G.; Ward, Samuel R.

    2014-01-01

    Background: Injury to the supraspinatus and infraspinatus tendons and the associated atrophic changes to the muscle remain a common clinical problem. Specifically, increased muscle stiffness has been implicated in failure of the repair and poor functional outcomes. We present a comparison of the passive mechanical properties and associated biochemical studies from patients with and without torn supraspinatus tendons. Methods: Muscle biopsy samples (n = 40) were obtained from twenty patients undergoing arthroscopic shoulder surgery. Passive mechanical tests of both individual fibers and fiber bundles as well as analysis of titin molecular weight and collagen content were performed. Results: At the fiber-bundle level, a significant increase in passive modulus was observed between intact supraspinatus samples (mean [and standard error], 237.41 ± 59.78 kPa) and torn supraspinatus samples (515.74 ± 65.48 kPa) (p < 0.05), a finding that was not observed at the single fiber level. Within the torn samples, elastic moduli in the supraspinatus were greater than in the infraspinatus at both the single fiber and the fiber-bundle level. There was a significant positive correlation between bundle elastic modulus and collagen content (r2 = 0.465) in the supraspinatus muscle as well as a significant positive correlation between tear size and bundle elastic modulus (r2 = 0.702) in the torn supraspinatus samples. Conclusions: Supraspinatus muscle passive tension increases in a tendon tear size-dependent manner after tendon injury. The increase in muscle stiffness appears to originate outside the muscle cell, in the extracellular matrix. Clinical Relevance: Muscle stiffness after rotator cuff tendon injury is more severe with large tears. This finding supports the concept of early intervention, when tendon tears are smaller, and interventions targeting the extracellular matrix. PMID:25320205

  3. Supraspinatus Intramuscular Calcified Hematoma or Necrosis Associated with Tendon Tear

    PubMed Central

    Lädermann, Alexandre; Genevay, Muriel; Abrassart, Sophie; Schwitzguébel, Adrien Jean-Pierre

    2015-01-01

    Introduction. Rotator cuff intramuscular calcification is a rare condition usually caused by heterotopic ossification and myositis ossificans. Case Presentation. We describe a patient with voluminous calcified mass entrapped in supraspinatus muscle associated with corresponding tendon tear. Histological examination corresponded to a calcified hematoma or necrosis. Patient was surgically managed with open excision of the calcified hematoma and rotator cuff arthroscopic repair. At 6 months, supraspinatus muscle was healed, and functional outcome was good. Discussion and Conclusion. We hypothesized that supraspinatus intramuscular calcified hematoma was responsible for mechanical stress on the tendon. This association has never been described. PMID:26380138

  4. Detection of partial-thickness tears in ligaments and tendons by Stokes-polarimetry imaging

    NASA Astrophysics Data System (ADS)

    Kim, Jihoon; John, Raheel; Walsh, Joseph T.

    2008-02-01

    A Stokes polarimetry imaging (SPI) system utilizes an algorithm developed to construct degree of polarization (DoP) image maps from linearly polarized light illumination. Partial-thickness tears of turkey tendons were imaged by the SPI system in order to examine the feasibility of the system to detect partial-thickness rotator cuff tear or general tendon pathology. The rotating incident polarization angle (IPA) for the linearly polarized light provides a way to analyze different tissue types which may be sensitive to IPA variations. Degree of linear polarization (DoLP) images revealed collagen fiber structure, related to partial-thickness tears, better than standard intensity images. DoLP images also revealed structural changes in tears that are related to the tendon load. DoLP images with red-wavelength-filtered incident light may show tears and related organization of collagen fiber structure at a greater depth from the tendon surface. Degree of circular polarization (DoCP) images exhibited well the horizontal fiber orientation that is not parallel to the vertically aligned collagen fibers of the tendon. The SPI system's DOLP images reveal alterations in tendons and ligaments, which have a tissue matrix consisting largely of collagen, better than intensity images. All polarized images showed modulated intensity as the IPA was varied. The optimal detection of the partial-thickness tendon tears at a certain IPA was observed. The SPI system with varying IPA and spectral information can improve the detection of partial-thickness rotator cuff tears by higher visibility of fiber orientations and thereby improve diagnosis and treatment of tendon related injuries.

  5. Genetic Response of Rat Supraspinatus Tendon and Muscle to Exercise

    PubMed Central

    Rooney, Sarah Ilkhanipour; Tobias, John W.; Bhatt, Pankti R.; Kuntz, Andrew F.; Soslowsky, Louis J.

    2015-01-01

    Inflammation is a complex, biologic event that aims to protect and repair tissue. Previous studies suggest that inflammation is critical to induce a healing response following acute injury; however, whether similar inflammatory responses occur as a result of beneficial, non-injurious loading is unknown. The objective of this study was to screen for alterations in a subset of inflammatory and extracellular matrix genes to identify the responses of rat supraspinatus tendon and muscle to a known, non-injurious loading condition. We sought to define how a subset of genes representative of specific inflammation and matrix turnover pathways is altered in supraspinatus tendon and muscle 1) acutely following a single loading bout and 2) chronically following repeated loading bouts. In this study, Sprague-Dawley rats in the acute group ran a single bout of non-injurious exercise on a flat treadmill (10 m/min, 1 hour) and were sacrificed 12 or 24 hours after. Rats in the chronic group ran 5 days/wk for 1 or 8 weeks. A control group maintained normal cage activity. Supraspinatus muscle and tendon were harvested for RNA extractions, and a custom Panomics QuantiGene 2.0 multiplex assay was used to detect 48 target and 3 housekeeping genes. Muscle/tendon and acute/chronic groups had distinct gene expression. Components of the arachidonic acid cascade and matrix metalloproteinases and their inhibitors were altered with acute and chronic exercise. Collagen expression increased. Using a previously validated model of non-injurious exercise, we have shown that supraspinatus tendon and muscle respond to acute and chronic exercise by regulating inflammatory- and matrix turnover-related genes, suggesting that these pathways are involved in the beneficial adaptations to exercise. PMID:26447778

  6. Tensile properties of a morphologically split supraspinatus tendon.

    PubMed

    Matsuhashi, Tomoya; Hooke, Alexander W; Zhao, Kristin D; Goto, Akira; Sperling, John W; Steinmann, Scott P; An, Kai-Nan

    2014-07-01

    The supraspinatus tendon consists morphologically of two sub-regions, anterior and posterior. The anterior sub-region is thick and tubular while the posterior is thin and strap-like. The purpose of this study was to compare the structural and mechanical properties of the anterior and posterior sub-regions of the supraspinatus tendon. The supraspinatus tendons from seven human cadaveric shoulders were morphologically divided into the anterior and posterior sub-regions. Length, width, and thickness were measured. A servo-hydraulic testing machine (MTS Systems Corporation, Minneapolis, MN) was used for tensile testing. The maximal load at failure, modulus of elasticity and ultimate tendon stress were calculated. Repeated measures were used for statistical comparisons. The mean anterior tendon cross-sectional area was 47.3 mm(2) and the posterior was 32.1 mm(2) . Failure occurred most often at the insertion site: anterior (5/7) and posterior (6/7). All parameters of the anterior sub-region were significantly greater than those of the posterior sub-region. The moduli of elasticity at the insertion site were 592.4 MPa in the anterior sub-region and 217.7 MPa in the posterior (P = 0.01). The ultimate failure loads were 779.2 N in the anterior sub-region and 335.6 N in the posterior (P = 0.003). The ultimate stresses were 22.1 MPa in the anterior sub-region and 11.6 MPa in the posterior (P = 0.008). We recognized that the anterior and posterior sub-regions of the SSP tendon have significantly different mechanical properties. In a future study, we need to evaluate how best to repair an SSP tendon considering these region-specific properties. PMID:24214830

  7. Repaired Supraspinatus Tendons in Clinically Improving Patients: Early Postoperative Findings and Interval Changes on MRI

    PubMed Central

    Lee, Jung Eun; Ryu, Kyung Nam; Rhee, Yong Girl; Yoon, So Hee; Park, So Young; Jin, Wook

    2015-01-01

    Objective To demonstrate and further determine the incidences of repaired supraspinatus tendons on early postoperative magnetic resonance imaging (MRI) findings in clinically improving patients and to evaluate interval changes on follow-up MRIs. Materials and Methods Fifty patients, who showed symptomatic and functional improvements after supraspinatus tendon repair surgery and who underwent postoperative MRI twice with a time interval, were included. The first and the second postoperative MRIs were obtained a mean of 4.4 and 11.5 months after surgery, respectively. The signal intensity (SI) patterns of the repaired tendon on T2-weighted images from the first MRI were classified into three types of heterogeneous high SI with fluid-like bright high foci (type I), heterogeneous high SI without fluid-like bright high foci (type II), and heterogeneous or homogeneous low SI (type III). Interval changes in the SI pattern, tendon thickness, and rotator cuff interval thickness between the two postoperative MRIs were evaluated. Results The SI patterns on the first MRI were type I or II in 45 tendons (90%) and type III in five (10%). SI decreased significantly on the second MRI (p < 0.050). The mean thickness of repaired tendons and rotator cuff intervals also decreased significantly (p < 0.050). Conclusion Repaired supraspinatus tendons exhibited high SI in 90% of clinically improving patients on MRI performed during the early postsurgical period. The increased SI and thickness of the repaired tendon decreased on the later MRI, suggesting a gradual healing process rather than a retear. PMID:25741199

  8. Multiscale mechanical integrity of human supraspinatus tendon in shear after elastin depletion.

    PubMed

    Fang, Fei; Lake, Spencer P

    2016-10-01

    Human supraspinatus tendon (SST) exhibits region-specific nonlinear mechanical properties under tension, which have been attributed to its complex multiaxial physiological loading environment. However, the mechanical response and underlying multiscale mechanism regulating SST behavior under other loading scenarios are poorly understood. Furthermore, little is known about the contribution of elastin to tendon mechanics. We hypothesized that (1) SST exhibits region-specific shear mechanical properties, (2) fiber sliding is the predominant mode of local matrix deformation in SST in shear, and (3) elastin helps maintain SST mechanical integrity by facilitating force transfer among collagen fibers. Through the use of biomechanical testing and multiphoton microscopy, we measured the multiscale mechanical behavior of human SST in shear before and after elastase treatment. Three distinct SST regions showed similar stresses and microscale deformation. Collagen fiber reorganization and sliding were physical mechanisms observed as the SST response to shear loading. Measures of microscale deformation were highly variable, likely due to a high degree of extracellular matrix heterogeneity. After elastase treatment, tendon exhibited significantly decreased stresses under shear loading, particularly at low strains. These results show that elastin contributes to tendon mechanics in shear, further complementing our understanding of multiscale tendon structure-function relationships. PMID:27472764

  9. Ultrasound assessment for grading structural tendon changes in supraspinatus tendinopathy: an inter-rater reliability study

    PubMed Central

    Hjarbaek, John; Eshoej, Henrik; Larsen, Camilla Marie; Vobbe, Jette; Juul-Kristensen, Birgit

    2016-01-01

    Aim To evaluate the inter-rater reliability of measuring structural changes in the tendon of patients, clinically diagnosed with supraspinatus tendinopathy (cases) and healthy participants (controls), on ultrasound (US) images captured by standardised procedures. Methods A total of 40 participants (24 patients) were included for assessing inter-rater reliability of measurements of fibrillar disruption, neovascularity, as well as the number and total length of calcifications and tendon thickness. Linear weighted κ, intraclass correlation (ICC), SEM, limits of agreement (LOA) and minimal detectable change (MDC) were used to evaluate reliability. Results ‘Moderate—almost perfect’ κ was found for grading fibrillar disruption, neovascularity and number of calcifications (k 0.60–0.96). For total length of calcifications and tendon thickness, ICC was ‘excellent’ (0.85–0.90), with SEM(Agreement) ranging from 0.63 to 2.94 mm and MDC(group) ranging from 0.28 to 1.29 mm. In general, SEM, LOA and MDC showed larger variation for calcifications than for tendon thickness. Conclusions Inter-rater reliability was moderate to almost perfect when a standardised procedure was applied for measuring structural changes on captured US images and movie sequences of relevance for patients with supraspinatus tendinopathy. Future studies should test intra-rater and inter-rater reliability of the method in vivo for use in clinical practice, in addition to validation against a gold standard, such as MRI. Trial registration number NCT01984203; Pre-results. PMID:27221128

  10. Repair versus shaving of partial-thickness articular-sided tears of the upper subscapularis tendon. A prospective randomized controlled trial

    PubMed Central

    RANDELLI, PIETRO; ARRIGONI, PAOLO; ALIPRANDI, ALBERTO; SDAO, SILVANA; RAGONE, VINCENZA; D’AMBROSI, RICCARDO; RANDELLI, FILIPPO; CABITZA, PAOLO; BANFI, GIUSEPPE

    2015-01-01

    Purpose the purpose of this study was to evaluate whether treating partial-thickness articular-sided tears of the upper subscapularis (SSC) tendon with a dedicated suture anchor would result in an internal rotation strength improvement compared with simple shaving of the SSC tendon and footprint. Methods twenty-six patients with a limited SSC tendon tear (equal or inferior to the most superior centimeter) in association with a posterosuperior cuff lesion were prospectively randomized to two treatments: repair with a dedicated suture anchor versus shaving of the tendon and footprint. The patients also underwent long head of the biceps (LHB) treatment and posterosuperior cuff tear repair. In each patient the following parameters were measured both preoperatively and at a minimum follow-up of 2.5 years: strength in internal rotation in the bear-hug testing position (using a digital tensiometer), DASH score and Constant scores. MRI assessment of tendon healing was performed at the final follow-up. Results twenty of the 26 patients (76%) were reviewed after a mean follow-up time of 42 months: 11 patients had undergone SSC tendon repair and nine simple shaving. At final follow-up no significant differences were found between the repaired and shaving group in strength in internal rotation (9.5 ± 3.8 kg versus 10.3±5.4 kg; p=0.7). The DASH score and Constant score also failed to show significant differences between the two groups. Furthermore, no significant difference in SSC tendon healing rate was observed on MRI evaluation. Conclusions partial-thickness articular-sided tear of the upper SSC tendon in association with a posterosuperior rotator cuff repair and LHB treatment, when limited to the superior centimeter of the SSC tendon, shows a comparable performance in terms of strength in internal rotation either after simple shaving or a tendon-to-bone repair. Level of evidence Level II, prospective comparative study. PMID:26889466

  11. PARTIAL ARTICULAR SUPRASPINATUS TENDON AVULSION (PASTA) LESION. CURRENT CONCEPTS IN REHABILITATION

    PubMed Central

    2016-01-01

    ABSTRACT Rotator cuff pathology can contribute to shoulder pain and may affect the performance of sport activities, work, and activities of daily living. The partial articular supraspinatus tendon avulsion (PASTA) lesion represents a very common type of rotator cuff pathology seen in rehabilitation. When conservative treatment fails, surgery is generally required. Success of recovery depends on several factors, including: repair techniques, healing process related to timing, rehabilitation programs, and patient compliance with home exercises. To date, most treatment modalities and rehabilitation programs are based on clinical experience rather than scientific evidence. Therefore, the purpose of this clinical commentary is to provide an overview on the PASTA lesion, discuss the common treatment approaches adopted to date and to propose a rehabilitation program based on the available scientific evidence. Level of Evidence 5 PMID:27274431

  12. Effect of preconditioning and stress relaxation on local collagen fiber re-alignment: inhomogeneous properties of rat supraspinatus tendon.

    PubMed

    Miller, Kristin S; Edelstein, Lena; Connizzo, Brianne K; Soslowsky, Louis J

    2012-03-01

    Repeatedly and consistently measuring the mechanical properties of tendon is important but presents a challenge. Preconditioning can provide tendons with a consistent loading history to make comparisons between groups from mechanical testing experiments. However, the specific mechanisms occurring during preconditioning are unknown. Previous studies have suggested that microstructural changes, such as collagen fiber re-alignment, may be a result of preconditioning. Local collagen fiber re-alignment is quantified throughout tensile mechanical testing using a testing system integrated with a polarized light setup, consisting of a backlight, 90 deg-offset rotating polarizer sheets on each side of the test sample, and a digital camera, in a rat supraspinatus tendon model, and corresponding mechanical properties are measured. Local circular variance values are compared throughout the mechanical test to determine if and where collagen fiber re-alignment occurred. The inhomogeneity of the tendon is examined by comparing local circular variance values, optical moduli and optical transition strain values. Although the largest amount of collagen fiber re-alignment was found during preconditioning, significant re-alignment was also demonstrated in the toe and linear regions of the mechanical test. No significant changes in re-alignment were seen during stress relaxation. The insertion site of the supraspinatus tendon demonstrated a lower linear modulus and a more disorganized collagen fiber distribution throughout all mechanical testing points compared to the tendon midsubstance. This study identified a correlation between collagen fiber re-alignment and preconditioning and suggests that collagen fiber re-alignment may be a potential mechanism of preconditioning and merits further investigation. In particular, the conditions necessary for collagen fibers to re-orient away from the direction of loading and the dependency of collagen reorganization on its initial distribution

  13. Effect of return to overuse activity following an isolated supraspinatus tendon tear on adjacent intact tendons and glenoid cartilage in a rat model.

    PubMed

    Reuther, Katherine E; Thomas, Stephen J; Sarver, Joseph J; Tucker, Jennica J; Lee, Chang-Soo; Gray, Chancellor F; Glaser, David L; Soslowsky, Louis J

    2013-05-01

    Rotator cuff tears are common conditions that can alter shoulder mechanics and may lead to damage of intact joint tissues. These injuries are of particular concern in populations who perform tasks requiring repetitive overhead activity (e.g., athletes and laborers) and who are likely to return to aggressive pre-injury activity levels despite limited understanding of the potentially damaging effects on the remaining tissues. Therefore, we investigated the effect of returning to overuse activity following a supraspinatus tear on shoulder function and the mechanical properties of the remaining intact tendons and glenoid cartilage. Forty rats underwent 4 weeks of overuse activity to create a tendinopathic condition followed by detachment of the supraspinatus tendon and were then randomized into two groups: continued overuse or cage activity. Ambulatory measurements were performed throughout the 8 weeks prior to euthaniasia, and properties of the adjacent tendons and cartilage were evaluated. Results demonstrated that shoulder function was not compromised in the return to overuse group. However, alterations of the glenoid cartilage and biceps tendon properties occurred. Our results help define the contributory roles of common mechanical injury mechanisms and provide a framework by which physicians could better prescribe long-term treatment strategies for patients. PMID:23280495

  14. Effect of Return to Overuse Activity Following an Isolated Supraspinatus Tendon Tear on Adjacent Intact Tendons and Glenoid Cartilage in a Rat Model

    PubMed Central

    Reuther, Katherine E.; Thomas, Stephen J.; Sarver, Joseph J.; Tucker, Jennica J.; Lee, Chang-Soo; Gray, Chancellor F.; Glaser, David L.; Soslowsky, Louis J.

    2013-01-01

    Rotator cuff tears are common conditions that can alter shoulder mechanics and may lead to damage of intact joint tissues. These injuries are of particular concern in populations who perform tasks requiring repetitive overhead activity (e.g., athletes and laborers) and who are likely to return to aggressive pre-injury activity levels despite limited understanding of the potentially damaging effects on the remaining tissues. Therefore, we investigated the effect of returning to overuse activity following a supraspinatus tear on shoulder function and the mechanical properties of the remaining intact tendons and glenoid cartilage. Forty rats underwent 4 weeks of overuse activity to create a tendinopathic condition followed by detachment of the supraspinatus tendon and were then randomized into two groups: continued overuse or cage activity. Ambulatory measurements were performed throughout the 8 weeks prior to euthaniasia, and properties of the adjacent tendons and cartilage were evaluated. Results demonstrated that shoulder function was not compromised in the return to overuse group. However, alterations of the glenoid cartilage and biceps tendon properties occurred. Our results help define the contributory roles of common mechanical injury mechanisms and provide a framework by which physicians could better prescribe long-term treatment strategies for patients. PMID:23280495

  15. 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. PMID:24570312

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

    PubMed Central

    Khor, Andrew Yu Keat; Wong, Steven Bak Siew

    2014-01-01

    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. PMID:24570312

  17. Collagen V-heterozygous and -null supraspinatus tendons exhibit altered dynamic mechanical behaviour at multiple hierarchical scales.

    PubMed

    Connizzo, Brianne K; Han, Lin; Birk, David E; Soslowsky, Louis J

    2016-02-01

    Tendons function using a unique set of mechanical properties governed by the extracellular matrix and its ability to respond to varied multi-axial loads. Reduction of collagen V expression, such as in classic Ehlers-Danlos syndrome, results in altered fibril morphology and altered macroscale mechanical function in both clinical and animal studies, yet the mechanism by which changes at the fibril level lead to macroscale functional changes has not yet been investigated. This study addresses this by defining the multiscale mechanical response of wild-type, collagen V-heterozygous and -null supraspinatus tendons. Tendons were subjected to mechanical testing and analysed for macroscale properties, as well as microscale (fibre re-alignment) and nanoscale (fibril deformation and sliding) responses. In many macroscale parameters, results showed a dose-dependent response with severely decreased properties in the null group. In addition, both heterozygous and null groups responded to load faster than in wild-type tendons via earlier fibre re-alignment and fibril stretch. However, the heterozygous group exhibited increased fibril sliding, while the null group exhibited no fibril sliding. These studies demonstrate that dynamic responses play an important role in determining overall function and that collagen V is a critical regulator in the development of these relationships. PMID:26855746

  18. 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

  19. Effect of fiber distribution and realignment on the nonlinear and inhomogeneous mechanical properties of human supraspinatus tendon under longitudinal tensile loading

    PubMed Central

    Lake, Spencer P.; Miller, Kristin S.; Elliott, Dawn M.; Soslowsky, Louis J.

    2010-01-01

    Tendon exhibits nonlinear stress-strain behavior that may be due, in part, to movement of collagen fibers through the extracellular matrix. While a few techniques have been developed to evaluate the fiber architecture of other soft tissues, the organizational behavior of tendon under load has not been determined. The supraspinatus tendon (SST) of the rotator cuff is of particular interest for investigation due to its complex mechanical environment and corresponding inhomogeneity. In addition, SST injury occurs frequently with limited success in treatment strategies, illustrating the need for a better understanding of SST properties. Therefore, the objective of this study was to quantitatively evaluate the inhomogeneous tensile mechanical properties, fiber organization and fiber realignment under load of human SST utilizing a novel polarized light technique. Fiber distributions were found to become more aligned under load, particularly during the low stiffness toe-region, suggesting that fiber realignment may be partly responsible for observed nonlinear behavior. Fiber alignment was found to correlate significantly with mechanical parameters, providing evidence for strong structure-function relationships in tendon. Human SST exhibits complex, inhomogeneous mechanical properties and fiber distributions, perhaps due to its complex loading environment. Surprisingly, histological grade of degeneration did not correlate with mechanical properties. PMID:19544524

  20. 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

  1. Multiscale regression modeling in mouse supraspinatus tendons reveals that dynamic processes act as mediators in structure-function relationships.

    PubMed

    Connizzo, Brianne K; Adams, Sheila M; Adams, Thomas H; Jawad, Abbas F; Birk, David E; Soslowsky, Louis J

    2016-06-14

    Recent advances in technology have allowed for the measurement of dynamic processes (re-alignment, crimp, deformation, sliding), but only a limited number of studies have investigated their relationship with mechanical properties. The overall objective of this study was to investigate the role of composition, structure, and the dynamic response to load in predicting tendon mechanical properties in a multi-level fashion mimicking native hierarchical collagen structure. Multiple linear regression models were investigated to determine the relationships between composition/structure, dynamic processes, and mechanical properties. Mediation was then used to determine if dynamic processes mediated structure-function relationships. Dynamic processes were strong predictors of mechanical properties. These predictions were location-dependent, with the insertion site utilizing all four dynamic responses and the midsubstance responding primarily with fibril deformation and sliding. In addition, dynamic processes were moderately predicted by composition and structure in a regionally-dependent manner. Finally, dynamic processes were partial mediators of the relationship between composition/structure and mechanical function, and results suggested that mediation is likely shared between multiple dynamic processes. In conclusion, the mechanical properties at the midsubstance of the tendon are controlled primarily by fibril structure and this region responds to load via fibril deformation and sliding. Conversely, the mechanical function at the insertion site is controlled by many other important parameters and the region responds to load via all four dynamic mechanisms. Overall, this study presents a strong foundation on which to design future experimental and modeling efforts in order to fully understand the complex structure-function relationships present in tendon. PMID:27067362

  2. Following rotator cuff tears, the remaining (intact) tendons are mechanically altered

    PubMed Central

    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 utilized an animal model of multiple rotator cuff tendon tears to investigate alterations in the remaining (intact) tendon mechanical properties at 4 and 8 weeks post-injury. Twenty-four animals served as uninjured controls, while seventy-two were divided among the tendon detachment groups (supraspinatus tendon detachment, supraspinatus+infraspinatus tendon detachment, supraspinatus+subscapularis tendon detachment). We found the remaining (intact) rotator cuff tendons have decreased mechanical properties in the presence of rotator cuff tears. Remaining (intact) subscapularis and infraspinatus tendon cross-sectional area increased, while tendon modulus decreased after both one and two tendon tears. Additionally, the remaining (intact) tendon cross-sectional areas continued to increase with time post-injury. These alterations could potentially lead to further tendon damage and tear progression. PMID:19095175

  3. Infraspinatus delamination does not affect supraspinatus tear repair.

    PubMed

    Zilber, Sébastien; Carillon, Yannick; Lapner, Peter C; Walch, Gilles; Nové-Josserand, Laurent

    2007-05-01

    Supraspinatus full-thickness tears with associated infraspinatus delamination are a frequent lesion, although the results of repair have not been reported. We retrospectively identified 35 patients treated for this cuff lesion among 378 open repaired full-thickness cuff tears. The aim of the study was to assess the subjective, objective, and anatomic outcomes of a subset of patients with supraspinatus tears involving delamination of the whole infraspinatus tendon. Thirty of the 35 patients were reviewed with magnetic resonance imaging at a minimum followup of 2 years (mean, 3.5 years; range, 2-6.5 years). The mean nonweighted Constant-Murley score at followup was 80/100 points, with an average gain of 17 points. Magnetic resonance imaging revealed all supraspinatus tendons but two were continuous. We observed no tear of the infraspinatus tendon, although a persistent delamination was present in 11 cases. One half of the patients had minor weakness in external rotation. One third of the infraspinatus muscles had minor fatty infiltration. Conservation of the infraspinatus tendon after closing the delamination did not seem to compromise the outcome of the supraspinatus repair. Avoiding resection of the infraspinatus delamination and treatment with simple curettage and closure yields satisfactory midterm functional and anatomic results. PMID:17308479

  4. Single ultrasound-guided platelet-rich plasma injection for treatment of supraspinatus tendinopathy in dogs

    PubMed Central

    Ho, Louisa K.; Baltzer, Wendy I.; Nemanic, Sarah; Stieger-Vanegas, Susanne M.

    2015-01-01

    The effect of a single platelet-rich plasma injection for supraspinatus tendinopathy was assessed in 10 dogs. Subjective (owner-assessed) improvement in lameness and function were seen in 40% of dogs with improved tendon heterogeneity and echogenicity in 60%. There were no significant changes in gait reaction forces 6 wk after treatment. PMID:26246631

  5. Effect of Scapular Dyskinesis on Supraspinatus Repair Healing in a Rat Model

    PubMed Central

    Reuther, Katherine E.; Tucker, Jennica J.; Thomas, Stephen J.; Vafa, Rameen P.; Liu, Stephen S.; Gordon, Joshua A.; Caro, Adam C.; Yannascoli, Sarah M.; Kuntz, Andrew F.; Soslowsky, Louis J.

    2015-01-01

    Background Rotator cuff tears are common conditions that often require surgical repair to improve function and relieve pain. Unfortunately, repair failure remains a common problem following rotator cuff repair surgery. Several factors may contribute to repair failure including age, tear size, and time from injury. However, the mechanical mechanisms resulting in repair failure are not well understood making clinical management difficult. Specifically, altered scapular motion (termed scapular dyskinesis) may be one important and modifiable factor contributing to the risk of repair failure. Therefore, the objective of this study was to determine the effect of scapular dyskinesis on supraspinatus tendon healing following repair. Methods A rat model of scapular dyskinesis was used. 70 adult male Sprague-Dawley rats (400-450 grams) were randomized into two groups: nerve transection of the accessory and long-thoracic nerves (SD) or sham nerve transection (Sham Control). Following this procedure, all rats underwent unilateral detachment and repair of the supraspinatus tendon. All rats were sacrificed at 2, 4, and 8 weeks after surgery. Shoulder function, passive joint mechanics, and tendon properties (mechanical, histological, organizational, and compositional) were evaluated. Results Scapular dyskinesis alters joint function and may lead to compromised supraspinatus tendon properties. Specifically, diminished mechanical properties, altered histology, and decreased tendon organization was observed for some parameters. Conclusion This study identifies scapular dyskinesis as one underlying mechanism leading to compromise of supraspinatus healing following repair. Identifying modifiable factors that lead to compromised tendon healing will help improve clinical outcomes following repair. Level of evidence Basic Science, in-vivo Animal Study. PMID:25745826

  6. High-Grade Articular, Bursal, and Intratendinous Partial-Thickness Rotator Cuff Tears: A Retrospective Study Comparing Functional Outcomes After Completion and Repair.

    PubMed

    Donohue, Nicholas K; Nickel, Brian T; Grindel, Steven I

    2016-01-01

    We conducted a study to assess the impact of tear location on functional outcomes in high-grade partial-thickness rotator cuff tears (PTRCTs) after arthroscopic completion and repair. Retrospectively, we evaluated the preoperative and postoperative findings of 60 patients who underwent arthroscopic completion and repair of Ellman grade 3 partial-thickness tears of the supraspinatus. The 60 patients were grouped by tear subtype (20 articular, 20 bursal, 20 intratendinous) as identified by preoperative imaging and confirmed at time of surgery. After surgery, the 3 subtypes showed similar significant (P < .001) improvements in American Shoulder and Elbow Surgeons scores (articular, 46.9, 85.1; bursal, 44.3, 80.3; intratendinous, 43.6, 86.1), Constant scores (articular, 54.3, 79.4; bursal, 49.9, 75.0; intratendinous, 56.8, 80.9), and visual analog scale scores (articular, 5.1, 1.2; bursal, 5.8, 1.6; intratendinous, 6.0, 1.2). Our study findings validate use of the current algorithm for Ellman grade 3 PTRCTs of the supraspinatus and advocate their completion and repair, regardless of tear location. PMID:27552462

  7. Anteriorly Based Partial Thickness Sternocleidomastoid Muscle Flap Following Parotidectomy.

    PubMed

    Dalmia, Deepak; Behera, Sanjaya Kumar; Bhatia, Jas Simran Singh

    2016-03-01

    The anteriorly based partial thickness sternocleidomastoid (SCM) muscle flap is among the various methods described to correct parotidectomy defects, but its indications and limitations are not clearly demonstrated in several reports. This study was done to test the aesthetic outcome of this method, its indications and limitations. At Dr. Babasaheb Ambedkar Memorial hospital, Mumbai, 20 patients presenting with benign parotid tumors underwent parotidectomy. 16 underwent superficial parotidectomy and 3 underwent adequate parotidectomy, 1 had total parotidectomy. The anteriorly based partial thickness SCM muscle flap was used to correct the contour deformity and to prevent Frey syndrome. The aesthetic result was evaluated by assessing and scoring the overall appearance of the scar, the degree of symmetry of the reconstructed parotid region and the site of the donor muscle in comparison to their contralateral normal sides. The overall aesthetic appearance was good in 17 patients, and moderate in 3 patients. 17/20 patients had an overall deep satisfaction with the result. The residual hollowness following total parotidectomy defect and the poor quality of scars were the main reasons affecting the aesthetic outcome. Superficial parotidectomy through modified Blair's incision with immediate reconstruction with anteriorly based partial thickness SCM flap allows a satisfactory aesthetic outcome and minimal donor site morbidity. Scores of the above two parameters were accessed. Patients' satisfaction was assessed by patients questionnaire. PMID:27066413

  8. Exercise protocol induces muscle, tendon, and bone adaptations in the rat shoulder

    PubMed Central

    Rooney, Sarah Ilkhanipour; Loro, Emanuele; Sarver, Joseph J.; Peltz, Cathryn D.; Hast, Michael W.; Tseng, Wei-Ju; Kuntz, Andrew F.; Liu, X. Sherry; Khurana, Tejvir S.; Soslowsky, Louis J.

    2014-01-01

    Summary Background: a rat model of supraspinatus overuse has suggested mechanisms governing tendon degeneration; however, delineating which changes are pathologic or simply physiologic adaptations to increased loading remains a question. The objective of this study was to develop and characterize a rat exercise model that induces systemic and local shoulder adaptations without mechanical injury to the supraspinatus tendon. Methods: exercise rats completed a treadmill training protocol for 12 weeks. Body, fat pad, and heart weights were determined. Supraspinatus tendon collagen content, cross-sectional area, and mechanical properties were measured. Supraspinatus muscle cross-sectional area, weight, and the expression of mitochondrial oxidative phosphorylation (OXPHOS) proteins were measured. Humeri were analyzed with μCT and mechanically tested. Results: exercise decreased fat pad mass. Supraspinatus muscle hypertrophied and had increased OXPHOS proteins. Humerus trabecular bone had increased anisotropic orientation, and cortical bone showed increased bone and tissue mineral density. Importantly, the supraspinatus tendon did not have diminished mechanical properties, indicating that this protocol was not injurious to the tendon. Conclusion: this study establishes the first rat exercise protocol that induces adaptations in the shoulder. Future research can use this as a comparison model to study how the supraspinatus tendon adapts to loading and undergoes degeneration with overuse. PMID:25767777

  9. 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

  10. EVALUATION OF THE EXTRACELLULAR MATRIX OF INJURED SUPRASPINATUS IN RATS

    PubMed Central

    Almeida, Luiz Henrique Oliveira; Ikemoto, Roberto; Mader, Ana Maria; Pinhal, Maria Aparecida Silva; Munhoz, Bruna; Murachovsky, Joel

    2016-01-01

    ABSTRACT Objective: To evaluate the evolution of injuries of the supraspinatus muscle by immunohistochemistry (IHC) and anatomopathological analysis in animal model (Wistar rats). Methods: Twenty-five Wistar rats were submitted to complete injury of the supraspinatus tendon, then subsequently sacrificed in groups of five animals at the following periods: immediately after the injury, 24h after the injury, 48h after, 30 days after and three months after the injury. All groups underwent histological and IHC analysis. Results: Regarding vascular proliferation and inflammatory infiltrate, we found a statistically significant difference between groups 1(control group) and 2 (24h after injury). IHC analysis showed that expression of vascular endothelial growth factor (VEGF) showed a statistically significant difference between groups 1 and 2, and collagen type 1 (Col-1) evaluation presented a statistically significant difference between groups 1 and 4. Conclusion: We observed changes in the extracellular matrix components compatible with remodeling and healing. Remodeling is more intense 24h after injury. However, VEGF and Col-1 are substantially increased at 24h and 30 days after the injury, respectively. Level of Evidence I, Experimental Study. PMID:26997907

  11. Change in the Pathologic Supraspinatus: A Three-Dimensional Model of Fiber Bundle Architecture within Anterior and Posterior Regions.

    PubMed

    Kim, Soo Y; Sachdeva, Rohit; Li, Zi; Lee, Dongwoon; Rosser, Benjamin W C

    2015-01-01

    Supraspinatus tendon tears are common and lead to changes in the muscle architecture. To date, these changes have not been investigated for the distinct regions and parts of the pathologic supraspinatus. The purpose of this study was to create a novel three-dimensional (3D) model of the muscle architecture throughout the supraspinatus and to compare the architecture between muscle regions and parts in relation to tear severity. Twelve cadaveric specimens with varying degrees of tendon tears were used. Three-dimensional coordinates of fiber bundles were collected in situ using serial dissection and digitization. Data were reconstructed and modeled in 3D using Maya. Fiber bundle length (FBL) and pennation angle (PA) were computed and analyzed. FBL was significantly shorter in specimens with large retracted tears compared to smaller tears, with the deeper fibers being significantly shorter than other parts in the anterior region. PA was significantly greater in specimens with large retracted tears, with the superficial fibers often demonstrating the largest PA. The posterior region was absent in two specimens with extensive tears. Architectural changes associated with tendon tears affect the regions and varying depths of supraspinatus differently. The results provide important insights on residual function of the pathologic muscle, and the 3D model includes detailed data that can be used in future modeling studies. PMID:26413533

  12. Change in the Pathologic Supraspinatus: A Three-Dimensional Model of Fiber Bundle Architecture within Anterior and Posterior Regions

    PubMed Central

    Kim, Soo Y.; Sachdeva, Rohit; Li, Zi; Lee, Dongwoon; Rosser, Benjamin W. C.

    2015-01-01

    Supraspinatus tendon tears are common and lead to changes in the muscle architecture. To date, these changes have not been investigated for the distinct regions and parts of the pathologic supraspinatus. The purpose of this study was to create a novel three-dimensional (3D) model of the muscle architecture throughout the supraspinatus and to compare the architecture between muscle regions and parts in relation to tear severity. Twelve cadaveric specimens with varying degrees of tendon tears were used. Three-dimensional coordinates of fiber bundles were collected in situ using serial dissection and digitization. Data were reconstructed and modeled in 3D using Maya. Fiber bundle length (FBL) and pennation angle (PA) were computed and analyzed. FBL was significantly shorter in specimens with large retracted tears compared to smaller tears, with the deeper fibers being significantly shorter than other parts in the anterior region. PA was significantly greater in specimens with large retracted tears, with the superficial fibers often demonstrating the largest PA. The posterior region was absent in two specimens with extensive tears. Architectural changes associated with tendon tears affect the regions and varying depths of supraspinatus differently. The results provide important insights on residual function of the pathologic muscle, and the 3D model includes detailed data that can be used in future modeling studies. PMID:26413533

  13. Distal Triceps Tendon Injuries.

    PubMed

    Keener, Jay D; Sethi, Paul M

    2015-11-01

    Acute triceps ruptures are an uncommon entity, occurring mainly in athletes, weight lifters (especially those taking anabolic steroids), and following elbow trauma. Accurate diagnosis is made clinically, although MRI may aid in confirmation and surgical planning. Acute ruptures are classified on an anatomic basis based on tear location and the degree of tendon involvement. Most complete tears are treated surgically in medically fit patients. Partial-thickness tears are managed according to the tear severity, functional demands, and response to conservative treatment. We favor an anatomic footprint repair of the triceps to provide optimal tendon to bone healing and, ultimately, functional outcome. PMID:26498552

  14. Do partial thickness, bursal side cuff tears affect outcome following arthroscopic subacromial decompression? A prospective comparative cohort study

    PubMed Central

    Al-Maiyah, Mohammed; Goodchild, Lorna; Fourie, J M Brendan; Finn, Paul; Rangan, Amar

    2014-01-01

    Background: The present study aimed to compare medium-term clinical outcomes of patients following arthroscopic subacromial decompression (ASAD): those with intact rotator cuff with two groups of increasing size of partial thickness bursal-side tears. Methods: Patients undergoing shoulder arthroscopy by a single surgeon had pre- and postoperative Constant scores prospectively recorded. Arthroscopic surgery included the assessment of any supraspinatus tears using the Ellman criteria, as well as ASAD and cuff debridement. Groups were created based on the status of rotator cuff and size of bursal tear. Outcome in these patient groups was then compared and analyzed Results: Seventy-four patients were suitable for inclusion in the study: 32 patients without a cuff tear; 21 patients with a cuff tear of 9 mm or less in length; and 21 patients with a cuff tear of 10 mm or more in length. Baseline characteristics of the three groups were similar. All three groups showed a significant improvement in their Constant scores following surgery. There was, however, no significant difference in Constant scores between the three groups. Conclusions: The results of the present study show that patients with varying sizes of bursal-side tears respond to ASAD as well as those with no rotator cuff tear.

  15. Tenascin-C and human tendon degeneration.

    PubMed Central

    Riley, G. P.; Harrall, R. L.; Cawston, T. E.; Hazleman, B. L.; Mackie, E. J.

    1996-01-01

    We investigated the distribution of tenascin in supraspinatus tendons to determine whether an alteration in tenascin expression was associated with human tendon degeneration. Tenascin was present in all of the tendons studied, although with two distinct patterns of expression. First, tenascin was associated with organized, fibrous regions of the tendon matrix that were typical of the normal tendon structure. This distribution is consistent with a role for tenascin in collagen fibril organization, perhaps maintaining the interface between fibrils and adjacent structures. Second, although tenascin was generally absent from poorly organized matrix in degenerate tendons, it was strongly associated with some rounded cells in disorganized fibrocartilaginous regions that were more abundant in pathological specimens. Tenascin was also found around infiltrating blood vessels, with more intense staining associated with a mononuclear cell infiltrate. Western blotting of tendon extracts showed differences in tenascin isoform expression, with only the small (200-kd) tenascin isoform found in normal tendons. Degenerate tendons also expressed the 300-kd isoform, consistent with a role for the larger tenascin isoform in tendon disease, potentially stimulating tenocyte proliferation, cell rounding, and fibrocartilaginous change. Proteolytic fragments of tenascin were detected but only in ruptured tendons, an indication of matrix remodeling in degenerate tendons, with fragment sizes consistent with the activity of matrix metalloproteinase enzymes. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:8780397

  16. Glycosaminoglycans of human rotator cuff tendons: changes with age and in chronic rotator cuff tendinitis.

    PubMed Central

    Riley, G P; Harrall, R L; Constant, C R; Chard, M D; Cawston, T E; Hazleman, B L

    1994-01-01

    OBJECTIVES--To analyse the glycosaminoglycans of the adult human rotator cuff tendon matrix, to characterise changes in the glycosaminoglycan composition with age and in chronic rotator cuff tendinitis. METHODS--Rotator cuff (supraspinatus) tendons (n = 84) and common biceps tendons (n = 26) were obtained from cadavers with no history of tendon pathology (age range 11-95 years). Biopsies of rotator cuff tendons (supraspinatus and subscapularis tendons, n = 53) were obtained during open shoulder surgery to repair shoulder lesions (age range 38-80 years). Glycosaminoglycans were extracted by papain digestion and analysed by cellulose acetate electrophoresis, the carbazole assay for uronic acid and the dimethylmethylene blue dye-binding assay for sulphated glycosaminoglycans. Some digests were analysed for keratan sulphate by 5D4 monoclonal antibody ELISA. Soluble proteoglycans were extracted in 4M guanidine hydrochloride and analysed by 4-15% SDS PAGE. RESULTS--The mean (SD) sulphated glycosaminoglycan (GAG) content of the normal cadaver supraspinatus tendon was 12.3 (4.3) micrograms/mg dry weight, between three and ten times greater than in the common biceps tendon [1.2 (0.6) micrograms/mg dry weight]. The major GAG was chondroitin sulphate [6.9 (2.6) micrograms/mg dry weight], with a smaller proportion of dermatan sulphate [2.5 (1.2) micrograms/mg dry weight]. In contrast, the common biceps tendon contained predominantly dermatan sulphate [0.8 (0.2) microgram/mg dry weight] with less chondroitin sulphate [0.2 (0.2) microgram/mg dry weight]. There was no difference in the concentration of hyaluronan in these tendons [9.3 (2.8) micrograms/mg dry weight and 10.8 (4.3) micrograms/mg dry weight respectively] and there was no significant change of hyaluronan with age. Keratan sulphate was a small but significant component of the supraspinatus tendon [0.43 (0.33) microgram/mg dry weight, n = 25], whereas there was little or none in the common biceps tendon [0.04 (0

  17. Clinical and Magnetic Resonance Imaging Results of Arthroscopic Repair of Intratendinous Partial-thickness Rotator Cuff Tears

    PubMed Central

    Xiao, Jian; Cui, Guo-Qing

    2015-01-01

    Background: Partial-thickness rotator cuff tears (PTRCTs) are being diagnosed more often because of high-resolution magnetic resonance imaging (MRI). Compared with articular and bursal side tears, there have been few studies about evaluating the clinical and structural outcomes after intratendinous tear repair. Methods: From 2008 to 2012, 33 consecutive patients with intratendinous PTRCTs underwent arthroscopic repair. All of them were retrospectively evaluated. The University of California at Los Angeles (UCLA) and constant scores were evaluated before operation and at the final follow-up. Postoperative cuff integrity was determined using MRI according to Sugaya's classification. Results: At the 2-year follow-up, the average UCLA score increased from 16.7 ± 1.9 to 32.5 ± 3.5, and the constant score increased from 66.2 ± 10.5 to 92.4 ± 6.9 (P < 0.001). Twenty seven patients received follow-up MRI examinations at an average of 15.2 months after surgery. Of these 27 patients, 22 (81.5%) had a healed tendon, and five patients had partial tears. There was no association between functional and anatomic results. Conclusions: For intratendinous PTRCT, clinical outcomes and tendon healing showed good results at a minimum 2-year after arthroscopic repair. PMID:26021507

  18. Subscapularis Tendon Repair Using Suture Bridge Technique

    PubMed Central

    Park, Yong Bok; Park, Young Eun; Koh, Kyoung Hwan; Lim, Tae Kang; Shon, Min Soo; Yoo, Jae Chul

    2015-01-01

    The subscapularis tendon plays an essential role in shoulder function. Although subscapularis tendon tears are less common than other rotator cuff tears, tears of the subscapularis tendon have increasingly been recognized with the advent of magnetic resonance imaging and arthroscopy. A suture bridge technique for the treatment of posterosuperior rotator cuff tears has provided the opportunity to improve the pressurized contact area and mean footprint pressure. However, suture bridge fixation of subscapularis tendon tears appears to be technically challenging. We describe an arthroscopic surgical technique for suture bridge repair of subscapularis tendon tears that obtains ideal cuff integrity and footprint restoration. Surgery using such a suture bridge technique is indicated for large tears, such as tears involving the entire first facet or more, tears with a disrupted lateral sling, and combined medium to large supraspinatus/infraspinatus tears. PMID:26052489

  19. 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 ...

  20. Spontaneous medial dislocation of the tendon of the long biceps brachii. An anatomic study of prevalence and pathomechanics.

    PubMed

    Petersson, C J

    1986-10-01

    Medial displacement of the tendon of the long biceps brachii muscle was analyzed in a dissection study on autopsy in 77 subjects, 42 men and 35 women. The tendon was found to be medially displaced in five shoulders in five different subjects (6.5%). Medial displacement of the tendon was always found in connection with full-thickness supraspinatus tendon ruptures. It is a common belief that the tendon is always displaced medially to the lesser tubercle riding over the subscapularis tendon. In the present series, this condition was found only in one case; in the other shoulders the tendon had slipped medially to the lesser tubercle under the subscapularis tendon, which was partially internally ruptured. In patients with rotator cuff lesions, medial displacement of the long biceps tendon might be one reason for pain over the front of the shoulder. PMID:3769261

  1. Tendon Innervation.

    PubMed

    Ackermann, Paul W; Salo, Paul; Hart, David A

    2016-01-01

    The regulation of tendon metabolism including the responses to loading is far from being well understood. During the last decade, however, accumulating data show that tendon innervation in addition to afferent functions, via efferent pathways has a regulatory role in tendon homeostasis via a wide range of neuromediators, which coordinate metabolic and neuro-inflammatory pathways.Innervation of intact healthy tendons is localized in the surrounding structures, i.e paratenon, endotenon and epitenon, whereas the tendon proper is practically devoid of neuronal supply. This anatomical finding reflects that the tendon metabolism is regulated from the tendon envelope, i.e. interfascicular matrix (see Chap. 1 ).Tendon innervation after injury and during repair, however, is found as extensive nerve ingrowth into the tendon proper, followed by a time-dependent emergence of different neuronal mediators, which amplify and fine-tune inflammatory and metabolic pathways in tendon regeneration. After healing nerve fibers retract to the tendon envelope.In tendinopathy innervation has been identified to consist of excessive and protracted nerve ingrowth in the tendon proper, suggesting pro-inflammatory, nociceptive and hypertrophic (degenerative) tissue responses.In metabolic disorders such as eg. diabetes impaired tendon healing has been established to be related to dysregulation of neuronal growth factors.Targeted approaches to the peripheral nervous system including neuronal mediators and their receptors may prove to be effective therapies for painful, degenerative and traumatic tendon disorders. PMID:27535247

  2. Effect of 1partial thickness actuation on stress concentration reduction near a hole

    NASA Technical Reports Server (NTRS)

    Sensharma, P. K.; Kadivar, M. H.; Haftka, R. T.

    1994-01-01

    Recently, there has been much interest in adaptive structures that can respond to a varying environment by changing their properties. Piezoelectric materials and shape memory alloys (SMA) are often used as partial thickness actuators to create such adaptivity by applied energy, usually electric curent. These actuators can be used to inducce strains in a structure and reduce stresses in regions of high stress concentration. Two of the present authors show that axisymmetric actuation strains applied troughout the thickness of a plate with a hole can reduce the stress concentration factor (SCF) in an isotropic plate from 3 to 2. However, in most cases actuators are expected to be bonded to or embedded in the plate, so that the actuation strains are applied in the actuators and not directly in the plate. The objective of this note is to show that such partial-thickness actuation cannot be used to reduce the stress concentration factor with axisymmetric actuations strain distribution.

  3. Rat rotator cuff tendon-to-bone healing properties are adversely affected by hypercholesterolemia

    PubMed Central

    Beason, David P.; Tucker, Jennica J.; Lee, Chang Soo; Edelstein, Lena; Abboud, Joseph A.; Soslowsky, Louis J.

    2014-01-01

    Background Rotator cuff tendon tears represent a major component of reported orthopaedic injuries. In addition, more than one quarter of U.S. adults either currently have high cholesterol levels or have reduced their previously high cholesterol levels through the use of pharmaceuticals. Our clinical data have already linked hypercholesterolemia to full-thickness rotator cuff tears, and experimental data from our laboratory have shown effects on native tendon properties in multiple species. The objective of this study was to evaluate healing of supraspinatus tendons in our rat rotator cuff injury model. We hypothesized that tendon healing would be inferior in rats receiving a high-cholesterol diet for 6 months compared with those receiving standard chow. Methods All animals were subjected to a unilateral supraspinatus detachment and repair surgery, with contralateral limbs serving as within-animal comparative data. Animals continued their respective diet courses, and their supraspinatus tendons were biomechanically or histologically evaluated at 2, 4, and 8 weeks postoperatively. Results Biomechanical testing revealed a significant reduction in normalized stiffness in hypercholesterolemic rats compared with controls at 4 weeks after injury, whereas histologic analyses showed no significant differences in collagen organization, cellularity, or cell shape between groups. Conclusion On the basis of our findings, hypercholesterolemia may have a detrimental biomechanical effect on tendon healing in our rat rotator cuff injury and repair model. Level of evidence Basic Science Study, Animal Model. PMID:24295837

  4. Inflammation activation and resolution in human tendon disease

    PubMed Central

    Dakin, Stephanie G; Martinez, Fernando O; Yapp, Clarence; Wells, Graham; Oppermann, Udo; Dean, Benjamin JF; Smith, Richard DJ; Wheway, Kim; Watkins, Bridget; Roche, Lucy; Carr, Andrew J

    2016-01-01

    Improved understanding of the role of inflammation in tendon disease is required to facilitate therapeutic target discovery. We studied supraspinatus tendons from patients experiencing pain before and after surgical subacromial decompression treatment. Tendons were classified as having early, intermediate or advanced disease and inflammation was characterized through activation of pathways mediated by Interferon, NF-κB, glucocorticoid receptor and STAT-6. Inflammation signatures revealed expression of genes and proteins induced by Interferon and NF-κB in early stage disease and genes and proteins induced by STAT-6 and glucocorticoid receptor activation in advanced stage disease. The pro-resolving proteins FPR2/ALX and ChemR23 were increased in early stage disease compared to intermediate-advanced stage disease. Patients who were pain-free post-treatment had tendons with increased expression of CD206 and ALOX15 mRNA compared to tendons from patients who continued to experience pain post-treatment, suggesting that these genes and their pathways may moderate tendon pain. Stromal cells from diseased tendons cultured in vitro showed increased expression of NF-κB and Interferon target genes after treatment with lipopolysaccharide or IFNγ compared to stromal cells derived from healthy tendons. We identified 15-epi Lipoxin A4, a stable lipoxin metabolite derived from aspirin treatment, as potentially beneficial in the resolution of tendon inflammation. PMID:26511510

  5. Three-dimensional ultrastructural analysis of development at the supraspinatus insertion by using focused ion beam/scanning electron microscope tomography in rats.

    PubMed

    Kanazawa, Tomonoshin; Gotoh, Masafumi; Ohta, Keisuke; Shiba, Naoto; Nakamura, Kei-Ichiro

    2016-06-01

    To obtain a successful outcome after rotator cuff repair, the repaired tendon must be biologically anchored to the bone. However, the histological structure at the repaired tendon-bone interface differs from that of the site of normal tendon insertion. Therefore, analyzing postnatal development in detail will contribute to understanding the repaired tendon-bone interface after rotator cuff repair. In this study, we analyzed postnatal development at the tendon-bone insertion in terms of temporal changes in SOX9/SCX expression and three-dimensional (3D) ultrastructure with FIB/SEM tomography, a new scanning electron microscopic method. Sixteen postnatal Sprague-Dawley rats were used for the study. One-, two-, three-, and four-week-old rats were sacrificed and both right and left shoulders were removed; eight normal supraspinatus tendon insertions were isolated for each time point. At each time point, four specimens were evaluated with fluorescent immunostaining for SOX9/SCX expression, and the remaining four specimens were evaluated with FIB/SEM tomography. Even in postnatal development, SOX9(+) /SCX(+) expression was observed at the tendon insertion; expression gradually decreased with postnatal development at the normal tendon insertion. In 3D ultrastructure, the morphology of the cells and the number/orientation of the cell processes drastically changed by postnatal week 4. The pattern of SOX9/SCX expression and 3D ultrastructural changes obtained in this study contribute to an understanding of the complicated development of normal tendon-bone insertion. Therefore, this study helps elucidate the pathophysiology of tendon-bone insertion, especially in cases of rotator cuff tear and repair. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:969-976, 2016. PMID:26599103

  6. Treatment of partial thickness burns with Zn-hyaluronan: lessons of a clinical pilot study

    PubMed Central

    Juhász, I.; Zoltán, P.; Erdei, I.

    2012-01-01

    Summary A clinical investigation to determine the effectiveness of Zn-hyaluronan gel for the treatment of partial thickness burns was carried out. 60 patients were enrolled in the study with an average of 3% TBSA burn. Exudation lasted 3 days, no infectious complications were observed. By day 14 the wounds of 52 patients have healed, average complete healing time was 10,5 days. An overall 93,3% healing rate was achieved within the planned observation period. Reduction of spontaneous and movementrelated pain was reduced to less than half of the initial values by day 5,5 and 6,3 respectively. Development of a thin, elastic, well tolerable and protective membrane-like layer was noted. This kept the wounds moist while clean during wound-healing, and was spontaneously shed as epithelisation proceeded. Zn-hyaluronan gel is a novel topical wound care product that has proven to be suitable for the treatment of partial thickness burns. PMID:23233826

  7. Estimating the time and temperature relationship for causation of deep-partial thickness skin burns.

    PubMed

    Abraham, John P; Plourde, Brian; Vallez, Lauren; Stark, John; Diller, Kenneth R

    2015-12-01

    The objective of this study is to develop and present a simple procedure for evaluating the temperature and exposure-time conditions that lead to causation of a deep-partial thickness burn and the effect that the immediate post-burn thermal environment can have on the process. A computational model has been designed and applied to predict the time required for skin burns to reach a deep-partial thickness level of injury. The model includes multiple tissue layers including the epidermis, dermis, hypodermis, and subcutaneous tissue. Simulated exposure temperatures ranged from 62.8 to 87.8°C (145-190°F). Two scenarios were investigated. The first and worst case scenario was a direct exposure to water (characterized by a large convection coefficient) with the clothing left on the skin following the exposure. A second case consisted of a scald insult followed immediately by the skin being washed with cool water (20°C). For both cases, an Arrhenius injury model was applied whereby the extent and depth of injury were calculated and compared for the different post-burn treatments. In addition, injury values were compared with experiment data from the literature to assess verification of the numerical methodology. It was found that the clinical observations of injury extent agreed with the calculated values. Furthermore, inundation with cool water decreased skin temperatures more quickly than the clothing insulating case and led to a modest decrease in the burn extent. PMID:26188899

  8. ERK2 dependent signaling contributes to wound healing after a partial-thickness burn

    SciTech Connect

    Satoh, Yasushi Saitoh, Daizoh; Takeuchi, Atsuya; Ojima, Kenichiro; Kouzu, Keita; Kawakami, Saki; Ito, Masataka; Ishihara, Masayuki; Sato, Shunichi; Takishima, Kunio

    2009-03-27

    Burn healing is a complex physiological process involving multiple cell activities, such as cell proliferation, migration and differentiation. Although extracellular signal-regulated kinases (ERK) have a pivotal role in regulating a variety of cellular responses, little is known about the individual functions of ERK isoform for healing in vivo. This study investigated the role of ERK2 in burn healing. To assess this, Erk2{sup +/-} mice generated by gene targeting were used. The resultant mice exhibited significant delay in re-epithelization of partial-thickness burns in the skin in comparison to wild-type. An in vitro proliferation assay revealed that keratinocytes from Erk2{sup +/-} mice grew significantly slower than those prepared from wild-type. These results highlight the importance of ERK2 in the process of burn healing.

  9. A Change of Traditional Method of Treatment of Partial Thickness Burn with Hydrofibre Dressings.

    PubMed

    Mitura, Kryspin; Osłowska, Jolanta; Mitura, Alicja

    2015-02-01

    Nearly 1% of population is affected with burn trauma annually. Among patients seeking advanced medical care almost 8% require hospital stay. Most burns are superficial and do not cause full thickness damage to the skin. Standard topical treatment of burn wounds with creams and ointments requires frequent dressings' changes. The healing process is long and expensive. The technological revolution, as occurred in the last decade in the field of dressing care allows us to introduce the use of advanced material solutions. Modern materials allow to shorten the treatment time, reduce the expenses and diminish the patient discomfort leading to good outcome. The study presented a case of four patients treated due to the partial thickness burn wound. Hydrofiber dressing with silver ions were introduced in the treatment. We observed good short and long term results. PMID:26146101

  10. Healing of partial thickness porcine skin wounds in a liquid environment.

    PubMed

    Breuing, K; Eriksson, E; Liu, P; Miller, D R

    1992-01-01

    This study employs a liquid-tight vinyl chamber for the topical fluid-phase treatment of experimental wounds in pigs. Continuous treatment with normal saline significantly reduced the early progression of tissue destruction in partial thickness burns. Uncovered burns formed a deep layer of necrosis (0.49 +/- 0.004 mm, mean +/- SD) although burn wounds covered with empty chambers demonstrated less necrosis (0.14 +/- 0.01 mm), fluid-treated wounds formed no eschar, and little tissue necrosis could be detected (less than 0.005 mm). Topical treatment with hypertonic dextran increased water flux across burn wounds by 0.24 ml/cm2/24 hr (mean, n = 95) over saline-treated wounds during the first 5 days after wounding. When partial thickness burn and excisional wounds were immersed in isotonic saline until healed, the daily efflux of water, protein, electrolytes, and glucose across the wound surface declined during healing to baseline values found in controls (saline-covered unwounded skin). The declining protein permeability was used as a reproducible, noninvasive, endogenous marker for the return of epithelial barrier function. Saline-treated excisional wounds healed within 8.6 +/- 0.6 days (mean +/- SD, n = 27) and burn wounds within 12.1 +/- 1.4 days (mean +/- SD, n = 15). Healing of fluid-treated wounds occurred without tissue maceration and showed less inflammation and less scar formation than healing of air exposed wounds (no attempt was made to compare rates of healing between air- and fluid-exposed wounds). We consider the fluid-filled chamber a potentially very useful diagnostic, monitoring, and delivery system for wound-healing research and for human wound therapy. PMID:1548868

  11. Intratendinous supraspinatus cyst as a cause of shoulder impingement

    PubMed Central

    Garg, Akshay; Karuppaiah, Karthik; Elias, David; Tavakkolizadeh, Adel

    2014-01-01

    We report the case of a 29-year-old gentleman with shoulder impingement. An articular-sided intratendinous supraspinatus cyst was identified as the cause of his symptoms. Arthroscopic cyst debridement resulted in a good outcome at 1-year follow-up. Cysts around the shoulder are a well described pathological entity. They consist of different categories, including intraosseus cysts of the humeral head and glenoid, paralabral cysts and cysts associated with the acromioclavicular joint. Although paralabral cysts that lie intramuscularly or between the muscle bellies have frequently been reported, this is the first report of an intratendinous supraspinatus cyst with an intact rotator cuff. We describe the case, its management and the postsurgical outcome. PMID:27582975

  12. Arthroscopic Repair of Articular Surface Partial-Thickness Rotator Cuff Tears: Transtendon Technique versus Repair after Completion of the Tear—A Meta-Analysis

    PubMed Central

    Woodmass, Jarret M.; Bois, Aaron J.; Boorman, Richard S.; Thornton, Gail M.

    2016-01-01

    Articular surface partial-thickness rotator cuff tears (PTRCTs) are commonly repaired using two different surgical techniques: transtendon repair or repair after completion of the tear. Although a number of studies have demonstrated excellent clinical outcomes, it is unclear which technique may provide superior clinical outcomes and tendon healing. The purpose was to evaluate and compare the clinical outcomes following arthroscopic repair of articular surface PTRCT using a transtendon technique or completion of the tear. A systematic review of the literature was performed following PRISMA guidelines and checklist. The objective outcome measures evaluated in this study were the Constant Score, American Shoulder and Elbow Surgeons score, Visual Analogue Scale, physical examination, and complications. Three studies met our criteria. All were prospective randomized comparative studies with level II evidence and published from 2012 to 2013. A total of 182 shoulders (mean age 53.7 years; mean follow-up 40.5 months) were analyzed as part of this study. Both procedures provided excellent clinical outcomes with no significant difference in Constant Score and other measures between the procedures. Both procedures demonstrated improved clinical outcomes. However, there were no significant differences between each technique. Further studies are required to determine the long-term outcome of each technique.

  13. Acute discrimination between superficial-partial and deep-partial thickness burns in a preclinical model with laser speckle imaging.

    PubMed

    Crouzet, Christian; Nguyen, John Quan; Ponticorvo, Adrien; Bernal, Nicole P; Durkin, Anthony J; Choi, Bernard

    2015-08-01

    A critical need exists for a robust method that enables early discrimination between superficial-partial and deep-partial thickness burn wounds. In this study, we report on the use of laser speckle imaging (LSI), a simple, non-invasive, optical imaging modality, to measure acute blood flow dynamics in a preclinical burn model. We used a heated brass comb to induce burns of varying severity to nine rats and collected raw speckle reflectance images over the course of three hours after burn. We induced a total of 12 superficial-partial and 18 deep-partial thickness burn wounds. At 3h after burn we observed a 28% and 44% decrease in measured blood flow for superficial-partial and deep-partial thickness burns, respectively, and that these reductions were significantly different (p=0.00007). This preliminary data suggests the potential role of LSI in the clinical management of burn wounds. PMID:25814299

  14. Tendon repair

    MedlinePlus

    ... Cannon DL. Flexor and extensor tendon injuries. In: Canale ST, Beaty JH, eds. Campbell's Operative Orthopaedics . ... Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, ...

  15. Four alginate dressings in the treatment of partial thickness wounds: a comparative experimental study.

    PubMed

    Agren, M S

    1996-03-01

    Alginate-based absorption materials for wound treatment are meeting with increasing clinical acceptance. The purpose of this study was to compare four different calcium alginate dressings (Algosteril, Comfeel Alginate, Kaltostat and Sorbsan) with respect to wound fluid retaining ability, adherence, dressing residues, epithelialisation and inflammatory cell infiltration using a standardised partial-thickness wound model in domestic pigs. Wound fluid spread laterally onto surrounding normal skin by about 40% more with Sorbsan than with the other alginate dressings after 24 h of treatment (P = 0.026). The corresponding figure after 66 h of treatment was 20% (P = 0.030). Algosteril (mean 1.7 [sem 0.3]) adhered significantly (P = 0.014) more to the wounds than Comfeel Alginate (mean 0.2 [0.2]). Kaltostat (mean 1.8 [0.3]) left significantly (P = 0.038) more dressing residues on the wound surface at dressing removal than the Comfeel Alginate dressing (mean 0.8 [0.2]). In the effect on epithelialisation or dermal inflammation there was no statistically significant difference at significance level 5% among the four alginate dressings, as assessed by light microscopy. In summary, the four alginate dressings showed significant differences in important handling characteristics and did not differ significantly in their effect on epithelialisation. PMID:8733355

  16. Effect of Topical Platelet-Rich Plasma on Burn Healing After Partial-Thickness Burn Injury

    PubMed Central

    Ozcelik, Umit; Ekici, Yahya; Bircan, Huseyin Yuce; Aydogan, Cem; Turkoglu, Suna; Ozen, Ozlem; Moray, Gokhan; Haberal, Mehmet

    2016-01-01

    Background To investigate the effects of platelet-rich plasma on tissue maturation and burn healing in an experimental partial-thickness burn injury model. Material/Methods Thirty Wistar albino rats were divided into 3 groups of 10 rats each. Group 1 (platelet-rich plasma group) was exposed to burn injury and topical platelet-rich plasma was applied. Group 2 (control group) was exposed to burn injury only. Group 3 (blood donor group) was used as blood donors for platelet-rich plasma. The rats were killed on the seventh day after burn injury. Tissue hydroxyproline levels were measured and histopathologic changes were examined. Results Hydroxyproline levels were significantly higher in the platelet-rich plasma group than in the control group (P=.03). Histopathologically, there was significantly less inflammatory cell infiltration (P=.005) and there were no statistically significant differences between groups in fibroblast development, collagen production, vessel proliferations, or epithelization. Conclusions Platelet-rich plasma seems to partially improve burn healing in this experimental burn injury model. As an initial conclusion, it appears that platelet-rich plasma can be used in humans, although further studies should be performed with this type of treatment. PMID:27262706

  17. Effect of Topical Platelet-Rich Plasma on Burn Healing After Partial-Thickness Burn Injury.

    PubMed

    Ozcelik, Umit; Ekici, Yahya; Bircan, Huseyin Yuce; Aydogan, Cem; Turkoglu, Suna; Ozen, Ozlem; Moray, Gokhan; Haberal, Mehmet

    2016-01-01

    BACKGROUND To investigate the effects of platelet-rich plasma on tissue maturation and burn healing in an experimental partial-thickness burn injury model. MATERIAL AND METHODS Thirty Wistar albino rats were divided into 3 groups of 10 rats each. Group 1 (platelet-rich plasma group) was exposed to burn injury and topical platelet-rich plasma was applied. Group 2 (control group) was exposed to burn injury only. Group 3 (blood donor group) was used as blood donors for platelet-rich plasma. The rats were killed on the seventh day after burn injury. Tissue hydroxyproline levels were measured and histopathologic changes were examined. RESULTS Hydroxyproline levels were significantly higher in the platelet-rich plasma group than in the control group (P=.03). Histopathologically, there was significantly less inflammatory cell infiltration (P=.005) and there were no statistically significant differences between groups in fibroblast development, collagen production, vessel proliferations, or epithelization. CONCLUSIONS Platelet-rich plasma seems to partially improve burn healing in this experimental burn injury model. As an initial conclusion, it appears that platelet-rich plasma can be used in humans, although further studies should be performed with this type of treatment. PMID:27262706

  18. A serum amyloid P-binding hydrogel speeds healing of partial thickness wounds in pigs

    PubMed Central

    Gomer, Richard H.; Pilling, Darrell; Kauvar, Lawrence M.; Ellsworth, Stote; Ronkainen, Sanna D.; Roife, David; Davis, Stephen C.

    2010-01-01

    During wound healing, some circulating monocytes enter the wound, differentiate into fibroblast-like cells called fibrocytes, and appear to then further differentiate into myofibroblasts, cells that play a key role in collagen deposition, cytokine release, and wound contraction. The differentiation of monocytes into fibrocytes is inhibited by the serum protein serum amyloid P (SAP). Depleting SAP at a wound site thus might speed wound healing. SAP binds to some types of agarose in the presence of Ca2+. We found that human SAP binds to an agarose with a KD of 7×10−8M and a Bmax of 2.1 μg SAP/mg wet weight agarose. Mixing this agarose 1: 5 w/v with 30 μg/mL human SAP (the average SAP concentration in normal serum) in a buffer containing 2mM Ca2+ reduced the free SAP concentration to ~0.02 μg/mL, well below the concentration that inhibits fibrocyte differentiation. Compared with a hydrogel dressing and a foam dressing, dressings containing this agarose and Ca2+ significantly increased the speed of wound healing in partial thickness wounds in pigs. This suggests that agarose/Ca2+ dressings may be beneficial for wound healing in humans. PMID:19660048

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

    PubMed Central

    Knobloch, Karsten

    2008-01-01

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

  20. Diabetes alters mechanical properties and collagen fiber re-alignment in multiple mouse tendons.

    PubMed

    Connizzo, Brianne K; Bhatt, Pankti R; Liechty, Kenneth W; Soslowsky, Louis J

    2014-09-01

    Tendons function to transfer load from muscle to bone through their complex composition and hierarchical structure, consisting mainly of type I collagen. Recent evidence suggests that type II diabetes may cause alterations in collagen structure, such as irregular fibril morphology and density, which could play a role in the mechanical function of tendons. Using the db/db mouse model of type II diabetes, the diabetic skin was found to have impaired biomechanical properties when compared to the non-diabetic group. The purpose of this study was to assess the effect of diabetes on biomechanics, collagen fiber re-alignment, and biochemistry in three functionally different tendons (Achilles, supraspinatus, patellar) using the db/db mouse model. Results showed that cross-sectional area and stiffness, but not modulus, were significantly reduced in all three tendons. However, the tendon response to load (transition strain, collagen fiber re-alignment) occurred earlier in the mechanical test, contrary to expectations. In addition, the patellar tendon had an altered response to diabetes when compared to the other two tendons, with no changes in fiber re-alignment and decreased collagen content at the midsubstance of the tendon. Overall, type II diabetes alters tendon mechanical properties and the dynamic response to load. PMID:24833253

  1. Diabetes Alters Mechanical Properties and Collagen Fiber Re-Alignment in Multiple Mouse Tendons

    PubMed Central

    Connizzo, Brianne K.; Bhatt, Pankti R.; Liechty, Kenneth W.; Soslowsky, Louis J.

    2014-01-01

    Tendons function to transfer load from muscle to bone through their complex composition and hierarchical structure, consisting mainly of type I collagen. Recent evidence suggests that type II diabetes may cause alterations in collagen structure, such as irregular fibril morphology and density, which could play a role in the mechanical function of tendons. Using the db/db mouse model of type II diabetes, the diabetic skin was found to have impaired biomechanical properties when compared to the non-diabetic group. The purpose of this study was to assess the effect of diabetes on biomechanics, collagen fiber re-alignment, and biochemistry in three functionally different tendons (Achilles, supraspinatus, patellar) using the db/db mouse model. Results showed that cross-sectional area and stiffness, but not modulus, were significantly reduced in all three tendons. However, the tendon response to load (transition strain, collagen fiber re-alignment) occurred earlier in the mechanical test, contrary to expectations. In addition, the patellar tendon had an altered response to diabetes when compared to the other two tendons, with no changes in fiber realignment and decreased collagen content at the midsubstance of the tendon. Overall, type II diabetes alters tendon mechanical properties and the dynamic response to load. PMID:24833253

  2. Comparison of three different dressings for partial thickness burns in children: study protocol for a randomised controlled trial

    PubMed Central

    2013-01-01

    Background In the paediatric population, pain and distress associated with burn injuries during wound care procedures remain a constant challenge. Although silver dressings are the gold standard for burn care in Australasia, very few high-level trials have been conducted that compare silver dressings to determine which will provide the best level of care clinically. Therefore, for paediatric patients in particular, identifying silver dressings that are associated with lower levels of pain and rapid wound re-epithelialisation is imperative. This study will determine whether there is a difference in time to re-epithelialisation and pain and distress experienced during wound care procedures among Acticoat™, Acticoat™ combined with Mepitel™ and Mepilex Ag™ dressings for acute, paediatric partial thickness burns. Methods/Design Children aged 0 to 15 years with an acute partial thickness (superficial partial to deep partial thickness inclusive) burn injury and a burn total body surface area of ≤10% will be eligible for the trial. Patients will be randomised to one of the three dressing groups: (1) Acticoat™ or (2) Acticoat™ combined with Mepitel™ or (3) Mepilex Ag™. A minimum of 28 participants will be recruited for each treatment group. Primary measures of pain, distress and healing will be repeated at each dressing change until complete wound re-epithelialisation occurs or skin grafting is required. Additional data collected will include infection status at each dressing change, physical function, scar outcome and scar management requirements, cost effectiveness of each dressing and staff perspectives of the dressings. Discussion The results of this study will determine the effects of three commonly used silver and silicone burn dressing combinations on the rate of wound re-epithelialisation and pain experienced during dressing procedures in acute, paediatric partial thickness burn injuries. Trial registration Australian New Zealand Clinical Trials

  3. Ciprofloxacin-loaded keratin hydrogels reduce infection and support healing in a porcine partial-thickness thermal burn.

    PubMed

    Roy, Daniel C; Tomblyn, Seth; Isaac, Kameel M; Kowalczewski, Christine J; Burmeister, David M; Burnett, Luke R; Christy, Robert J

    2016-07-01

    Infection is a leading cause of morbidity and mortality in burn patients. Current therapies include silver-based creams and dressings, which display limited antimicrobial effectiveness and impair healing. The need exists for a topical, point-of-injury antibiotic treatment that provides sustained antimicrobial activity without impeding wound repair. Fitting this description are keratin-based hydrogels, which are fully biocompatible and support the slow-release of antibiotics. Here we develop a porcine model of an infected partial-thickness burn to test the effects of ciprofloxacin-loaded keratin hydrogels on infection and wound healing. Partial-thickness burns were inoculated with either Pseudomonas aeruginosa or Methicillin-resistant Staphylococcus aureus, resulting in infections that persisted for >2 weeks that exceeded 10(5) and 10(6) cfu per gram of tissue, respectively. Compared to silver sulfadiazine, ciprofloxacin-loaded keratin hydrogel treatment significantly reduced the amount of P. aeruginosa and S. aureus in the burn by >99% on days 4, 7, 11, and 15 postinjury. Further, burns treated with ciprofloxacin-loaded keratin hydrogels exhibited similar healing patterns as uninfected burns with regards to reepithelialization, macrophage recruitment, and collagen deposition and remodeling. The ability of keratin hydrogels to deliver antibiotics to fight infection and support healing of partial-thickness burns make them a strong candidate as a first-line burn therapy. PMID:27238250

  4. Growth factor therapy in patients with partial-thickness burns: a systematic review and meta-analysis.

    PubMed

    Zhang, Yi; Wang, Tao; He, Jinguang; Dong, Jiasheng

    2016-06-01

    Growth factor (GF) therapy has shown promise in treating a variety of refractory wounds. However, evidence supporting its routine use in burn injury remains uncertain. We performed this systematic review and meta-analysis assessing randomised controlled trials (RCTs) to investigate efficacy and safety of GFs in the management of partial-thickness burns. Electronic searches were conducted in PubMed and the Cochrane databases. Endpoint results analysed included wound healing and scar formation. Thirteen studies comprising a total of 1924 participants with 2130 wounds (1131 GF receiving patients versus 999 controls) were identified and included, evaluating the effect of fibroblast growth factor (FGF), epidermal growth factor (EGF) and granulocyte macrophage-colony stimulating factor (GM-CSF) on partial-thickness burns. Topical application of these agents significantly reduced healing time by 5·02 (95% confidence interval, 2·62 to 7·42), 3·12 (95% CI, 1·11 to 5·13) and 5·1 (95% CI, 4·02 to 6·18) days, respectively, compared with standard wound care alone. In addition, scar improvement following therapy with FGF and EGF was evident in terms of pigmentation, pliability, height and vascularity. No significant increase in adverse events was observed in patients receiving GFs. These results suggested that GF therapy could be an effective and safe add-on to standard wound care for partial-thickness burns. High-quality, adequately powered trials are needed to further confirm the conclusion. PMID:25040572

  5. Aqueous humor outflow effects of partial thickness channel created by a femtosecond laser in ex-vivo human eyes

    NASA Astrophysics Data System (ADS)

    Chai, Dongyul; Chaudhary, Gautam; Kurtz, Ron; Juhasz, Tibor

    2007-02-01

    The reduced outflow rate caused by the increased resistance through trabecular meshwork (TM) has been thought to be the main reason for elevated intraocular pressure (IOP). It has been demonstrated that femtosecond laser pulses tuned to 1.7 μm wavelength can create the partial thickness channel in the sclera in ex vivo human eyes [1] and aqueous outflow can be increased by these channels in porcine eyes [2]. It was also shown that the outflow rate is reduced over time in ex vivo human eyes [3]. Therefore, the control experiment without laser treatment at the same condition was conducted and showed that outflow was reduced by 1.5 +/- 0.8 μl/min at 15mmHg and 1.8 +/- 1.0 μl/min at 25mmHg. However, the outflow rate increased by 0.26 μl/min at 15mmHg and 0.15 μl/min at 25mmHg after the partial thickness channel was created, meaning the amount of increased outflow rate might be more than measured considering the outflow reduction in control experiment. We suggest that the femtosecond laser created partial thickness channel can increase the outflow rate and delay the progression of glaucoma.

  6. Tendon latch

    SciTech Connect

    Watkins, B. J.

    1985-01-01

    A latch connects tendons run from a floating platform to a socket in a foundation on the sea floor. The latch includes a latch body having a plurality of dogs disposed within and urgible outward from the latch body. A piston is releasably disposed within the latch body above the dogs and moves downwardly when released to urge the dogs outwardly from the body into latching engagement with the socket. A trigger mechanism in the latch releases the piston when the latch body lands in the socket and contacts a trigger pin projecting upwardly from the bottom of the socket. A series of wedges are disposed exteriorally on the body and inhibit lateral movement of the body relative to the socket when the tendon is subjected to a cycle bending loads.

  7. Posterior Tibial Tendon Dysfunction

    MedlinePlus

    ... when the posterior tibial tendon becomes inflamed or torn. As a result, the tendon may not be ... repetitive use. Once the tendon becomes inflamed or torn, the arch will slowly fall (collapse) over time. ...

  8. Treatment of supraspinatus tendinopathy with ultrasound guided dry needling

    PubMed Central

    Settergren, Roy

    2013-01-01

    Objective The purpose of this case study is to describe the treatment of a patient with tendinopathy using sonographically guided dry needling. Tendinopathies are a highly prevalent problem in musculoskeletal medicine, and no one form of treatment has gained universal acceptance as being superior to another. Clinical Features A 30-year-old woman with a 4-month history of anterolateral right shoulder pain was diagnosed with supraspinatus tendinopathy upon physical examination, which was confirmed with diagnostic sonography. Intervention and Outcome Sonography was used to guide an acupuncture needle into the pathologic tissue to induce a humoral healing response. Therapeutic exercise was also prescribed. At 10-day follow-up, increased echogenicity was found in the previously heterogenous hypoechoic areas. The patient also experienced a subjective resolution of her shoulder pain, which did not return with increased physical activity. Conclusions Sonographically guided dry needling was shown to be beneficial for this patient as evident by sonographic changes pre- and postprocedure. PMID:23997721

  9. Tendon, tendon healing, hyperlipidemia and statins

    PubMed Central

    Esenkaya, Irfan; Unay, Koray

    2011-01-01

    Summary Both hyperlipidemia and metabolic syndrome have adverse effect on tendon structure. Atorvastatin is most widely used antihyperlipidemic drug. Statins have adverse effects on the tendon. Many studies have analyzed the relationship between atorvastatin and skeletal muscles. Atorvastatin administered after the surgical repair of a ruptured tendon appears to affect revascularization, collagenization, inflammatory cell infiltration, and collagen construction. Therefore, further investigations on the effects of atorvastatin on tendon healing are needed. PMID:23738266

  10. MRI-Arthroscopic Correlation in Rotator Cuff Tendon Pathologies; A Comparison between Various Centers

    PubMed Central

    Sefidbakht, Sepideh; Momenzadeh, Omid Reza; Dehghani, Sakineh; Gerami, Hadi

    2016-01-01

    Background: Magnetic resonance imaging (MRI) has long been considered a perfect imaging study for evaluation of shoulder pathologies despite occasional discrepancies between MR reports and arthroscopic findings. In this study we aim to evaluate impact of imaging center as an indicator of image quality on accuracy of MRI reports in diagnosis of rotator cuff tendon pathologies. Methods: We reviewed MR reports of 64 patients who underwent arthroscopy in university center hospital. MRIs were done in various centers including both university-affiliated and out-centers. All studies were reported by two radiologists in consensus unaware of the arthroscopic results or previous reports. An inter-observer agreement analysis using the kappa statistics was performed to determine consistency among imaging and surgical reports. Results: Kappa values for out-centers were as follows: 0.785 for biceps, 0.469 for suscapularis, 0.846 for supraspinatus and 0.785 for infraspinatus tendons. In university centers values were 0.799 for biceps, 0.802 for suscapularis, 0.789 for supraspinatus and 0.770 for infraspinatus tendons. Conclusion: Image reporting in university centers with proficient sequences increased accuracy of diagnosis in 3/4 of evaluated features and showed subtle decreased inter-observer agreement in 1/4 of features. Uniformity of the scanners and protocols as well as evaluation on a workstation rather than hard copies cumulatively resulted in a meaningful increase in the accuracy of the same radiologists in diagnosis of rotator cuff tendon tear. PMID:27200392

  11. Random Pattern Vertically Oriented, Partial Thickness Buccinator Myomucosal Flap for Intraoral Reconstruction:A Report of Two Cases

    PubMed Central

    Rahpeyma, Amin; khajehahmadi, Saeedeh

    2016-01-01

    Introduction: Reconstruction of the oral cavity with a flap design containing the buccal mucosa and buccinator muscle but excluding the facial artery and vein is the topic of these case reports. Case Reports: This article uses random pattern vertically oriented partial thickness buccinator myomucosal flap for intraoral reconstruction in two cases. The first was for lining the mandibular anterior vestibule in a trauma patient. The second was for oral side coverage of bone graft in special cleft patient. In both patients, this flap survived and good bone coverage with non-keratinized mucosa was obtained. Conclusion: Thin long buccal myomucosal flap not including facial artery and vein can survive. PMID:27429953

  12. Partial Flexor Tendon Laceration Assessment: Interobserver and Intraobserver Reliability.

    PubMed

    Barker, B Justin; Kolovich, Gregory P; Klinefelter, Ryan D

    2016-01-01

    Accurate assessment of partial-thickness flexor tendon lacerations in the hand is difficult owing to the subjectivity of evaluation. In this study, we created 12 partial-thickness flexor tendon lacerations in a cadaveric hand, evaluated the accuracy of 6 orthopedic residents and 4 fellowship-trained hand surgeons in estimating the percentage thickness of each laceration, and assessed the groups' interobserver and intraobserver agreement. The 10 participants estimated each laceration independently and on 2 separate occasions and indicated whether they would repair it. The actual thickness of each laceration was calculated from measurements made with a pair of digital microcalipers. Overall estimates differed significantly from calibrated measurements. Estimates grouped by residents and fellowship-trained hand surgeons also differed significantly. Third-year residents were the most accurate residents, and fellowship-trained hand surgeons were more accurate than residents. Overall interobserver agreement was poor for both readings. There was moderate overall intraobserver agreement. Fellowship-trained hand surgeons and first-year residents had the highest intraobserver agreement. These results highlight the difficulty in accurately assessing flexor tendon lacerations. Accuracy appears not to improve with surgeon experience. PMID:26991579

  13. Endoscopic adhesiolysis for extensive tibialis posterior tendon and Achilles tendon adhesions following compound tendon rupture

    PubMed Central

    Lui, Tun Hing

    2013-01-01

    Tendon adhesion is one of the most common causes of disability following tendon surgery. A case of extensive peritendinous adhesions of the Achilles tendon and tibialis posterior tendon after compound rupture of the tendons was reported. This was managed by endoscopic adhesiolysis of both tendons. The endoscopic approach allows early postoperative mobilisation which can relieve the tendon adhesion. PMID:24045762

  14. ARTHROSCOPY FOR TREATMENT OF REFRACTORY CALCIFIC TENDONITIS OF THE SHOULDER

    PubMed Central

    Fernandes, Marcos Rassi; Fernandes, Rui José

    2015-01-01

    Objective: To evaluate the results from arthroscopic treatment in patients with calcific tendonitis of the shoulder. Methods: Between September 2001 and June 2006, 55 patients with calcific tendonitis of the shoulder that was resistant to conservative treatment were evaluated, with follow-up of 12 to 70 months. The mean age was 42 years, ranging from 30 to 64 years; 44 patients were female (80%). There were 37 right shoulders, and 63.63% of the cases were on the dominant side. Pain was the main symptom, and the mean time between onset of symptoms and arthroscopy was 38 months (range: five to 120 months). The tendon affected was the supraspinatus in 42 cases, the infraspinatus in 11 cases and an association between these in two cases. Acromioplasty was carried out in 12 patients (21.82%) and subacromial bursectomy was performed in all cases. Results: According to the UCLA criteria, 46 cases were excellent and six were good, making a total of 52 satisfactory results (94.54%). Conclusion: Arthroscopic treatment of calcific tendonitis of the shoulder appears to be an effective method, with high rates of satisfactory results. Associated acromioplasty is not necessary. PMID:27019839

  15. Pressurized liquid filled tendons

    SciTech Connect

    Burns, G.E.

    1987-05-12

    This patent describes an apparatus for detecting a leak in a tension leg platform tendon, comprising: a fluid-tight tensioned tubular tendon, the tendon connected on its upper end to a buoyant offshore structure and on its lower end to an anchor means. The anchor means is connected to the sea floor; means for supplying liquid to the tendon; means for pressurizing the liquid in excess of the maximum hydrostatic pressure exerted by the sea water on the tendon; and means for monitoring pressure, the means monitoring variations in liquid pressure to the tendon.

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

    PubMed

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

    2016-01-01

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

  17. 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

  18. Transverse Compression of Tendons.

    PubMed

    Samuel Salisbury, S T; Paul Buckley, C; 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. PMID:26833218

  19. Achilles tendon: US examination

    SciTech Connect

    Fornage, B.D.

    1986-06-01

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

  20. The effects of exercise using PNF in patients with a supraspinatus muscle tear

    PubMed Central

    Kim, Jwa-jun; Lee, Sang-yeol; Ha, Kyungjin

    2015-01-01

    [Purpose] The aim of this study was to examine the effects of proprioceptive neuromuscular facilitation techniques and simple exercise on subjective pain reduction and blood flow velocity in supraspinatus tear patients and to evaluate muscle recovery. [Subjects and Methods] The 20 subjects of this study were diagnosed with supraspinatus tears by MRI. The subjects have performed PNF techniques and Simple exercise for 12 weeks. [Results] After 12 weeks of proprioceptive neuromuscular facilitation techniques and simple exercise, the blood flow velocity, Visual Analogue Scale, and disabilities of the arm, shoulder, and hand score showed statistically significant difference. Also, the difference between the proprioceptive neuromuscular facilitation techniques and simple exercise was statistically significant. [Conclusion] In conclusion, 12 weeks of proprioceptive neuromuscular facilitation treatment and simple exercise therapy had no effect on pain reduction in patients with supraspinatus tear, but in terms of functionality, the proprioceptive neuromuscular facilitation treatment was effective. PMID:26356542

  1. Biomechanics of Tendon Transfers.

    PubMed

    Livermore, Andrew; Tueting, Jonathan L

    2016-08-01

    The transfer of tendons in the upper extremity is a powerful technique to restore function to a partially paralyzed hand. The biomechanical principles of muscle tension and tendon excursion dictate motor function both in the native as well as transferred states. Appropriately tensioning transferred tendons to maximize the function of the associated muscle remains an area of focused research. Newer methods of tendon coaptation have proven similar in strength to the standard Pulvertaft weave, affording more options to the surgeon. PMID:27387073

  2. 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

  3. Achilles tendon repair

    MedlinePlus

    ... ency/article/007643.htm Achilles tendon repair To use the sharing features on this page, please enable JavaScript. Your Achilles tendon joins your calf muscle to your heel. You can tear your Achilles tendon if you land hard on your heel during sports, from a ...

  4. Pressurized gas filled tendons

    SciTech Connect

    Silcox, W. H.

    1985-06-04

    Pressurized gas filled tubular tendons provide a means for detecting leaks therein. Filling the tendon with a gaseous fluid provides increased buoyancy and reduces the weight supported by the buoyant structure. The use of a corrosion inhibiting gaseous fluid reduces the corrosion of the interior tendon wall.

  5. Radial Nerve Tendon Transfers.

    PubMed

    Cheah, Andre Eu-Jin; Etcheson, Jennifer; Yao, Jeffrey

    2016-08-01

    Radial nerve palsy typically occurs as a result of trauma or iatrogenic injury and leads to the loss of wrist extension, finger extension, thumb extension, and a reduction in grip strength. In the absence of nerve recovery, reconstruction of motor function involves tendon transfer surgery. The most common donor tendons include the pronator teres, wrist flexors, and finger flexors. The type of tendon transfer is classified based on the donor for the extensor digitorum communis. Good outcomes have been reported for most methods of radial nerve tendon transfers as is typical for positional tendon transfers not requiring significant power. PMID:27387076

  6. Overload and neovascularization of shoulder tendons in volleyball players

    PubMed Central

    2012-01-01

    Background In overhead sports like volleyball, the onset of a rotator cuff tendinopathy due to functional overload is a common observation. An angiofibroblastic etiopathogenesis has been hypothesized, whereby a greater anaerobic metabolism occurs in critical zones of the tendon with a lower degree of vascularization; this would induce collagen and extracellular matrix degradation, that could then trigger a compensatory neovascularization response. We performed a clinical observational study of 80 elite volleyball players, monitoring the perfusion values of the supraspinatus tendons by oximetry. Results No statistically significant differences were found between the oximetry data and age, sex or years of sports activity, nor when comparing the right and left arm or the dominant and non-dominant arm. A statistically significant difference was found for the dominant arm values in relation to the competitive role, higher values being obtained in outside hitters (62.7%) than middle hitters (53.7%) (p = 0.01), opposite hitters (55.5%) (p = 0.02) and libero players (54.4%) (p = 0.008), whereas there were no differences in setters (56.2%) (p > 0.05). Conclusions The different tendon vascularization values found in players with different roles in the team may be attributed to a response to the specific biomechanical demands posed by the different overhead throwing roles. PMID:22853746

  7. Tendon Structure and Composition.

    PubMed

    Thorpe, Chavaunne T; Screen, Hazel R C

    2016-01-01

    Tendons are soft, fibrous tissues that connect muscle to bone. Their main function is to transfer muscle generated force to the bony skeleton, facilitating movement around a joint, and as such they are relatively passive, inelastic structures, able to resist high forces. Tendons are predominantly composed of collagen, which is arranged in a hierarchical manner parallel to the long axis of the tendon, resulting in high tensile strength. Tendon also contains a range of non-collagenous proteins, present in low amounts, which nevertheless have important functional roles. In this chapter, we describe general tendon composition and structure, and discuss how variations in composition and structure at different levels of the tendon hierarchy confer specific mechanical properties, which are related to tendon function. PMID:27535244

  8. Efficacy of a bio-electric dressing in healing deep, partial-thickness wounds using a porcine model .

    PubMed

    Harding, Andrew C; Gil, Joel; Valdes, Jose; Solis, Michael; Davis, Stephen C

    2012-09-01

    Numerous physical modalities have been used in attempts to augment the healing process, including ultrasound, low- energy light therapy, and electrical stimulation (ES). ES has been shown to benefit tissue repair in a variety of wound types, but variations in study designs, administration, and parameters render its application in clinical practice somewhat unconventional. A dressing was designed to generate an electric potential of 0.6 V to 0.7 V in the presence of moisture, thereby delivering a sustained micro-current without the need for an external power source. The purpose of this study was to examine the effects of this bio-electric dressing (BED) on deep, partial-thickness wounds using six female specific pathogen-free animals and a well established porcine model for wound healing. Wounds (10 mm x 7 mm x 0.5 mm) were created in paravertebral and thoracic areas of these animals using a specialized electrokeratome and covered with the active polyester BED and a polyurethane film dressing (n = 30) (treatment) or an inactive polyester and film dressing (n = 30). Using an epidermal migration assay, wounds were assessed daily from day 4 through day 8 post-wounding. Differences in the proportion of wounds healed were statistically significant (P <0.001) on days 5 and 6 post-wounding. These results show BED is more effective than a control dressing treatment with moisture-retentive dressings in this animal model. Controlled clinical studies are warranted to elucidate the potential clinical implications of this treatment modality. PMID:22933701

  9. Role of Endogenous TRPV1 Agonists in a Post-Burn Pain Model of Partial-Thickness Injury

    PubMed Central

    Green, Dustin; Ruparel, Shivani; Roman, Linda; Henry, Michael A.; Hargreaves, Kenneth M.

    2013-01-01

    Oxidized linoleic acid metabolites (OLAMs) are a class of endogenous transient receptor potential vanilloid 1 (TRPV1) channel agonists released upon exposure of tissue to transient noxious temperatures. These lipid compounds also contribute to inflammatory and heat allodynia. As persistent pain after a burn injury represents a significant clinical challenge for treatment, we developed an in vivo rat model of partial thickness cutaneous thermal injury and examined whether TRPV1 and specific OLAM metabolites play a role in mediating post-burn pain injury. This peripheral model of burn injury had marked thermal allodynia peaking at 24 hours post thermal injury, with allodynia being maintained for up to 7 days. Immunohistochemical characterization of tissue taken from injury site revealed an increase of leukocyte/macrophage infiltration that was co-localized with TRPV1-positive fibers. Utilizing this peripheral thermal injury model we found that pharmacological blockade of peripheral TRPV1 receptors reduced thermal allodynia by about 67%. Moreover, there was a significant increase in OLAM levels compared to naïve controls in hindpaw skin biopsies. Additional studies on metabolism of [C14]-linoleic acid in skin biopsies revealed the role of the cytochrome P450 (CYP) system in mediating the metabolism of linoleic acid post thermal injury. Finally, we demonstrated direct inhibition of OLAMs using OLAM antibodies and indirect inhibition using the CYP inhibitor ketoconazole significantly reduced post-burn thermal allodynia. Collectively, these findings point to a novel role of the OLAMs and CYP-related enzymes in generating post-burn allodynia via activation of peripheral TRPV1. PMID:23891895

  10. Tendon Functional Extracellular Matrix

    PubMed Central

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

    2015-01-01

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

  11. Novel fiber-based pure chitosan scaffold for tendon augmentation: biomechanical and cell biological evaluation.

    PubMed

    Nowotny, J; Aibibu, D; Farack, J; Nimtschke, U; Hild, M; Gelinsky, M; Kasten, P; Cherif, Ch

    2016-07-01

    One possibility to improve the mechanical properties after tendon ruptures is augmentation with a scaffold. Based on wet spinning technology, chitosan fibres were processed to a novel pure high-grade multifilament yarn with reproducible quality. The fibres were braided to obtain a 3D tendon scaffold. The CS fibres and scaffolds were evaluated biomechanically and compared to human supraspinatus (SSP) tendons. For the cytobiological characterization, in vitro cell culture experiments with human mesenchymal stem cells (hMSC) were performed. Three types of 3D circular braided scaffolds were fabricated. Significantly, higher ultimate stress values were measured for scaffold with larger filament yarn, compared to scaffold with smaller filament yarn. During cultivation over 28 days, the cells showed in dependence of isolation method and/or donor a doubling or tripling of the cell number or even a six-fold increase on the CS scaffold, which was comparable to the control (polystyrene) or in the case of cells obtained from human biceps tendon even higher proliferation rates. After 14 days, the scaffold surface was covered homogeneously with a cell layer. In summary, the present work demonstrates that braided chitosan scaffolds constitute a straightforward approach for designing tendon analogues, maintaining important flexibility in scaffold design and providing favourable mechanical properties of the resulting construct. PMID:27109607

  12. Principles of Tendon Transfer.

    PubMed

    Wilbur, Danielle; Hammert, Warren C

    2016-08-01

    Tendon transfers provide a substitute, either temporary or permanent, when function is lost due to neurologic injury in stroke, cerebral palsy or central nervous system lesions, peripheral nerve injuries, or injuries to the musculotendinous unit itself. This article reviews the basic principles of tendon transfer, which are important when planning surgery and essential for an optimal outcome. In addition, concepts for coapting the tendons during surgery and general principles to be followed during the rehabilitation process are discussed. PMID:27387072

  13. 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

  14. Riser and tendon management system

    SciTech Connect

    Devlin, P.V.

    1992-02-18

    This patent describes a riser and tendon management system. It comprises means to set nominal conditions for the risers and tendons; means to measure actual riser and tendon conditions; means to compare the actual and nominal conditions of the risers and tendons; and means responsive to a differential between the actual and nominal riser and tendon conditions, which difference exceeds specified limits, and recommending corrective action to bring the risers and tendons back to within nominal conditions.

  15. Tendon Transfers for Tetraplegia.

    PubMed

    Bednar, Michael S

    2016-08-01

    It is estimated that 65% to 75% of patients with cervical spinal cord injuries could benefit from upper extremity tendon transfer surgery. The goals of surgery are to restore elbow extension, as well as hand pinch, grasp, and release. Patients who have defined goals, actively participate in therapy, and understand expected outcomes, appear to have the highest satisfaction following tendon transfer procedures. PMID:27387082

  16. Fatigue loading of tendon

    PubMed Central

    Shepherd, Jennifer H; Screen, Hazel R C

    2013-01-01

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

  17. Peroneal Tendon Injuries

    MedlinePlus

    ... ACFAS | Información en Español Advanced Search Home » Foot & Ankle Conditions » Peroneal Tendon Injuries Text Size Print Bookmark ... foot run side-by-side behind the outer ankle bone. One peroneal tendon attaches to the outer ...

  18. Advantages of collagen based biological dressings in the management of superficial and superficial partial thickness burns in children

    PubMed Central

    Mathangi Ramakrishnan, K.; Babu, M.; Mathivanan; Jayaraman, V.; Shankar, J.

    2013-01-01

    Summary Collagen based dressings for acute burn wound management have been extensively used in India, particularly in the city of Chennai. Due to the high levels of humidity in our city, closed dressings become infected and treatment with topical antimicrobials, like Silver Sulfadiazine cream, quickly become desiccated. Collagen membrane dressings were manufactured by the biomaterial laboratory of the Central Leather Research Institute (CLRI), Government of India in Chennai, and then the process was patented. Collagen was extracted from bovine skin and Achilles tendons, and then reconstituted. This was used on burn wounds as dressings after clearance from the Institutional Review Board and Ethics Committees of the Hospital and CLRI. Continued research in this field to enable resulted in the design of silver sulphadiazine loaded alginate microspheres which were embedded in the reconstituted collagen. Controlled delivery of silver sulphadiazine. This collagen membrane was used in chronic infected burns. Low molecular weight heparin was given subcutaneously to improve wound healing in burn injuries and collagen membrane dressings were also applied. After several trials the process technology was patented. The advantages and disadvantages of the collagen membrane cover is elaborated in a group of 487 pediatric burn patients. The trial was conducted at the burn unit of Kanchi Kamakoti Childs Trust Hospital (KKCTH) in Chennai, India. PMID:24133405

  19. Influence of Hyperlipidemia on the Treatment of Supraspinatus Tendinopathy With or Without Tear

    PubMed Central

    2016-01-01

    Objective To investigate the influence of hyperlipidemia on the treatment of supraspinatus tendinopathy, with or without tear. Methods We retrospectively reviewed the data of patients with shoulder pain and patients with supraspinatus tendinopathy, with or without tear, were included in the study. Exclusion criteria were prior shoulder surgery, prior steroid injection, neurological diseases that could lead to shoulder pain, and use of lipid-lowering medication. According to the serum lipid profiles, patients were assigned to either the hyperlipidemia or non-hyperlipidemia group. By analyzing the numeric rating scale (NRS) before treatment, and at 2 weeks and 8 weeks after treatment, we compared the difference in treatment effect between the two groups. Results No significant baseline difference was found among the two groups for age, gender, body mass index, duration of pain, side of pain, range of motion of affected shoulder, or physical examination. On the repeated-measures analysis of variance, NRS scores significantly decreased with time for both groups (p<0.001). When analyzing the effect of time between the subjects factor, there was significant difference in the treatment effect between the two groups (p<0.001), namely NRS was less decreased in the hyperlipidemia group. Conclusion We found that hyperlipidemia may be an adversely affecting factor in the treatment of supraspinatus tendinopathy with or without tear. PMID:27446783

  20. A method to test contractility of the supraspinatus muscle in mouse, rat, and rabbit.

    PubMed

    Valencia, Ana P; Iyer, Shama R; Pratt, Stephen J P; Gilotra, Mohit N; Lovering, Richard M

    2016-02-01

    The rotator cuff (RTC) muscles not only generate movement but also provide important shoulder joint stability. RTC tears, particularly in the supraspinatus muscle, are a common clinical problem. Despite some biological healing after RTC repair, persistent problems include poor functional outcomes with high retear rates after surgical repair. Animal models allow further exploration of the sequela of RTC injury such as fibrosis, inflammation, and fatty infiltration, but there are few options regarding contractility for mouse, rat, and rabbit. Histological findings can provide a "direct measure" of damage, but the most comprehensive measure of the overall health of the muscle is contractile force. However, information regarding normal supraspinatus size and contractile function is scarce. Animal models provide the means to compare muscle histology, imaging, and contractility within individual muscles in various models of injury and disease, but to date, most testing of animal contractile force has been limited primarily to hindlimb muscles. Here, we describe an in vivo method to assess contractility of the supraspinatus muscle and describe differences in methods and representative outcomes for mouse, rat, and rabbit. PMID:26586911

  1. Sustainable antimicrobial effect of silver sulfadiazine-loaded nanosheets on infection in a mouse model of partial-thickness burn injury.

    PubMed

    Ito, Keisuke; Saito, Akihiro; Fujie, Toshinori; Nishiwaki, Keisuke; Miyazaki, Hiromi; Kinoshita, Manabu; Saitoh, Daizoh; Ohtsubo, Shinya; Takeoka, Shinji

    2015-09-01

    Partial-thickness burn injury has the potential for reepithelialization and heals within 3weeks. If the wound is infected by bacteria before reepithelization, however, the depth of disruption increases and the lesion easily progresses to the full-thickness dermal layers. In the treatment of partial-thickness burn injury, it is important to prevent the wound area from bacterial infection with an antimicrobial dressing. Here, we have tested the antimicrobial properties of polymeric ultra-thin films composed of poly(lactic acid) (termed "PLA nanosheets"), which have high flexibility, adhesive strength and transparency, and silver sulfadiazine (AgSD), which exhibits antimicrobial efficacy. The AgSD-loaded nanosheet released Ag(+) for more than 3days, and exerted antimicrobial efficacy against methicillin-resistant Staphylococcus aureus (MRSA) in an in vitro Kirby-Bauer test. By contrast, a cell viability assay indicated that the dose of AgSD used in the PLA nanosheets did not show significant cytotoxicity toward fibroblasts. In vivo evaluation using a mouse model of infection in a partial-thickness burn wound demonstrated that the nanosheet significantly reduced the number of MRSA bacteria on the lesion (more than 10(5)-fold) and suppressed the inflammatory reaction, thereby preventing a protracted wound healing process. PMID:26079191

  2. In vitro effects of glutamate and N-methyl-D-aspartate receptor (NMDAR) antagonism on human tendon derived cells.

    PubMed

    Dean, Benjamin John Floyd; Snelling, Sarah J B; Dakin, Stephanie Georgina; Javaid, Muhammad Kassim; Carr, Andrew Jonathan

    2015-10-01

    It is known that extracellular glutamate concentrations are increased in tendinopathy but the effects of glutamate upon human tendon derived cells are unknown. The primary purpose was to investigate the effect of glutamate exposure on human tendon-derived cells in terms of viability, protein, and gene expression. The second purpose was to assess whether NMDAR antagonism would affect the response of tendon-derived cells to glutamate exposure. Human tendon-derived cells were obtained from supraspinatus tendon tissue obtained during rotator cuff repair (tendon tear derived cells) and from healthy hamstring tendon tissue (control cells). The in vitro impact of glutamate exposure and NMDAR antagonism (MK-801) was measured using the Alamar blue cell viability assay, immunocytochemistry, and quantitative real-time PCR. Glutamate reduced cell viability at 24 h in tendon tear derived cells but not in control cells at concentrations of 7.5 mM and above. Cell viability was significantly reduced after 72 h of 1.875 mM glutamate in both cell groups; this deleterious effect was attenuated by NMDAR antagonism with 10 µM MK-801. Both 24 and 72 h of 1.875 mM glutamate exposure reduced Type 1 alpha 1 collagen (COL1A1) and Type 3 alpha 1 collagen (COL3A1) gene expression, but increased Aggrecan gene expression. We propose that these effects of glutamate on tendon derived cells including reduced cell viability and altered matrix gene expression contribute to the pathogenesis of tendinopathy. PMID:26041147

  3. How Obesity Affects Tendons?

    PubMed

    Abate, Michele; Salini, Vincenzo; Andia, Isabel

    2016-01-01

    Several epidemiological and clinical observations have definitely demonstrated that obesity has harmful effects on tendons. The pathogenesis of tendon damage is multi-factorial. In addition to overload, attributable to the increased body weight, which significantly affects load-bearing tendons, systemic factors play a relevant role. Several bioactive peptides (chemerin, leptin, adiponectin and others) are released by adipocytes, and influence tendon structure by means of negative activities on mesenchymal cells. The ensuing systemic state of chronic, sub-clinic, low-grade inflammation can damage tendon structure. Metabolic disorders (diabetes, impaired glucose tolerance, and dislipidemia), frequently associated with visceral adiposity, are concurrent pathogenetic factors. Indeed, high glucose levels increase the formation of Advanced Glycation End-products, which in turn form stable covalent cross-links within collagen fibers, modifying their structure and functionality.Sport activities, so useful for preventing important cardiovascular complications, may be detrimental for tendons if they are submitted to intense acute or chronic overload. Therefore, two caution rules are mandatory: first, to engage in personalized soft training program, and secondly to follow regular check-up for tendon pathology. PMID:27535258

  4. A new technique for MR elastography of the supraspinatus muscle: A gradient-echo type multi-echo sequence.

    PubMed

    Ito, Daiki; Numano, Tomokazu; Mizuhara, Kazuyuki; Takamoto, Koichi; Onishi, Takaaki; Nishijo, Hisao

    2016-10-01

    Magnetic resonance elastography (MRE) can measure tissue stiffness quantitatively and noninvasively. Supraspinatus muscle injury is a significant problem among throwing athletes. The purpose of this study was to develop an MRE technique for application to the supraspinatus muscle by using a conventional magnetic resonance imaging (MRI). MRE acquisitions were performed with a gradient-echo type multi-echo MR sequence at 100Hz pneumatic vibration. A custom-designed vibration pad was used as a pneumatic transducer in order to adapt to individual shoulder shapes. In a gradient-echo type multi-echo MR sequence, without motion encoding gradient (MEG) that synchronizes with vibrations, bipolar readout gradient lobes achieved a similar function to MEG (MEG-like effect). In other words, a dedicated MRE sequence (built-in MEG) is not always necessary for MRE. In this study, 7 healthy volunteers underwent MRE. We investigated the effects of direction of the MEG-like effect and selected imaging planes on the patterns of wave propagation (wave image). The results indicated that wave images showed clear wave propagation on a condition that the direction of the MEG-like effect was nearly perpendicular to the long axis of the supraspinatus muscle, and that the imaging plane was superior to the proximal supraspinatus muscle. This limited condition might be ascribed to specific features of fibers in the supraspinatus muscle and wave reflection from the boundaries of the supraspinous fossa. The mean stiffness of the supraspinatus muscle was 10.6±3.17kPa. Our results demonstrated that using MRE, our method can be applied to the supraspinatus muscle by using conventional MRI. PMID:27374984

  5. Regulatory role of collagen V in establishing mechanical properties of tendons and ligaments is tissue dependent.

    PubMed

    Connizzo, Brianne K; Freedman, Benjamin R; Fried, Joanna H; Sun, Mei; Birk, David E; Soslowsky, Louis J

    2015-06-01

    Patients with classic (type I) Ehlers-Danlos syndrome (EDS), characterized by heterozygous mutations in the Col5a1 and Col5a2 genes, exhibit connective tissue hyperelasticity and recurrent joint dislocations, indicating a potential regulatory role for collagen V in joint stabilizing soft tissues. This study asked whether the contribution of collagen V to the establishment of mechanical properties is tissue dependent. We mechanically tested four different tissues from wild type and targeted collagen V-null mice: the flexor digitorum longus (FDL) tendon, Achilles tendon (ACH), the anterior cruciate ligament (ACL), and the supraspinatus tendon (SST). Area was significantly reduced in the Col5a1(ΔTen/ΔTen) group in the FDL, ACH, and SST. Maximum load and stiffness were reduced in the Col5a1(ΔTen/ΔTen) group for all tissues. However, insertion site and midsubstance modulus were reduced only for the ACL and SST. This study provides evidence that the regulatory role of collagen V in extracellular matrix assembly is tissue dependent and that joint instability in classic EDS may be caused in part by insufficient mechanical properties of the tendons and ligaments surrounding each joint. PMID:25876927

  6. Achilles Tendon Disorders

    MedlinePlus

    ... after periods of rest, then improves somewhat with motion but later worsens with increased activity. Tenderness, or ... foot and ankle and evaluate the range of motion and condition of the tendon. The extent of ...

  7. 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 ...

  8. Subrupture Tendon Fatigue Damage

    PubMed Central

    Laudier, Damien M.; Shine, Jean H.; Basta-Pljakic, Jelena; Jepsen, Karl J.; Schaffler, Mitchell B.; Flatow, Evan L.

    2016-01-01

    The mechanical and microstructural bases of tendon fatigue, by which damage accumulates and contributes to degradation, are poorly understood. To investigate the tendon fatigue process, rat flexor digitorum longus tendons were cyclically loaded (1–16 N) until reaching one of three levels of fatigue damage, defined as peak clamp-to-clamp strain magnitudes representing key intervals in the fatigue life: i) Low (6.0%–7.0%); ii) Moderate (8.5%–9.5%); and iii) High (11.0%–12.0%). Stiffness, hysteresis, and clamp-to-clamp strain were assessed diagnostically (by cyclic loading at 1–8 N) before and after fatigue loading and following an unloaded recovery period to identify mechanical parameters as measures of damage. Results showed that tendon clamp-to-clamp strain increased from pre- to post-fatigue loading significantly and progressively with the fatigue damage level (p≤0.010). In contrast, changes in both stiffness and hysteresis were significant only at the High fatigue level (p≤0.043). Correlative microstructural analyses showed that Low level of fatigue was characterized by isolated, transverse patterns of kinked fiber deformations. At higher fatigue levels, tendons exhibited fiber dissociation and localized ruptures of the fibers. Histomorphometric analysis showed that damage area fraction increased significantly with fatigue level (p≤0.048). The current findings characterized the sequential, microstructural events that underlie the tendon fatigue process and indicate that tendon deformation can be used to accurately assess the progression of damage accumulation in tendons. PMID:18683881

  9. 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

  10. Tendon of the long head of the biceps originating from the rotator cuff – An uncommon anatomical variation: case report☆

    PubMed Central

    Andreoli, Carlos Vicente; Esteves, Leonardo Roure; Figueiredo, Eduardo; Belangero, Paulo Santoro; de Castro Pochini, Alberto; Ejnisman, Benno

    2015-01-01

    Anatomical variations at the origin of the biceps tendon have been described by several authors, but occurrences of an origin in the supraspinatus are rare. It is unclear whether this variation might contribute toward pathological conditions of the shoulder. Our objective here was to describe a case of an anatomical variation in the origin of the tendon of the long head of the biceps. The clinical information, preoperative images and arthroscopic images relating to a patient with an aberrant origin of the long head of the biceps, which was observed during shoulder arthroscopy, were reviewed. In this case study, the origin of the biceps was found in the rotator cuff, without any origin from the supraglenoid tubercle or upper labrum. This variant did not seem to contribute toward the pathological condition of the shoulder, and standard treatment for the concomitant condition was sufficient for treating it. PMID:26962493

  11. Intra-articular changes precede extra-articular changes in the biceps tendon following rotator cuff tears in a rat model

    PubMed Central

    Peltz, Cathryn D.; Hsu, Jason E.; Zgonis, Miltiadis H.; Trasolini, Nicholas A.; Glaser, David L.; Soslowsky, Louis J.

    2011-01-01

    Background Biceps tendon pathology is common with rotator cuff tears. The mechanisms for biceps changes, and therefore its optimal treatment, are unknown. Our objective was to determine the effect of rotator cuff tears on regional biceps tendon pathology. We hypothesized that histological and compositional changes would appear before organizational changes, both would appear before mechanical changes, and changes would begin at the tendon’s insertion site. Methods Sixty-five Sprague-Dawley rats received either detachment of supraspinatus and infraspinatus tendons or sham surgery. Rats were sacrificed at 1, 4 or 8 weeks for regional measurements of histological, compositional, organizational (1, 4 and 8 weeks) or mechanical properties (4 and 8 weeks only). Results One week following tendon detachments, decreased organization and more rounded cell shape were found in the intra-articular space of the biceps tendon. Aggrecan expression was increased along the entire length of the tendon while all other compositional changes were at the tendon’s proximal insertion into bone only. With time, this disorganization and more rounded cell shape extended the length of the tendon. Organizational and cell shape changes also preceded detrimental mechanical changes, as decreased modulus in the intra-articular space was found after 8 weeks. Conclusions Results support a degenerative component to pathology in the biceps tendon. Additionally, changes resembling a tendon exposed to compressive loading occurring first in the intra-articular space indicate that the biceps tendon plays an increased role as a load bearing structure against the humeral head in the presence of rotator cuff tears. PMID:21816629

  12. Platelet-Rich Plasma Treatment With Physical Therapy in Chronic Partial Supraspinatus Tears

    PubMed Central

    Ilhanli, Ilker; Guder, Necip; Gul, Murat

    2015-01-01

    Background: Despite the insufficient evidence, due to potential contribution to the improvement, platelet-rich plasma (PRP) is emerging as a promising method. Objectives: The aim of this study was to assess the effectiveness of PRP injection in partial supraspinatus tears by comparing with physical therapy (PT). Patients and Methods: Seventy patients with chronic partial supraspinatus tears in magnetic resonance imaging were randomized into two groups; PRP (n = 35) and PT (n = 35). Before the treatment, at the end of the treatment and at the 12th month after the end of the treatment, range of motion (ROM), visual analog scale (VAS) for pain, Disabilities of Arm, Shoulder and Hand questionnaire (DASH), Neer’s, Hawkins’ and drop arm tests and Beck Depression Inventory were investigated. Results: Statistical analysis was made for 62 subjects (PRP group, n = 30; PT group, n = 32). There were no differences between the groups according to demographic data. At the 12th month after the end of the treatment, significant improvement in ROM was detected in both groups, pain was reduced significantly in both groups and improvement of the DASH score was observed in both groups. At all the evaluation steps, increases in ROM degrees were significantly higher in the PT group than the PRP group. For VAS in activity and in rest, after the treatment, improvement was higher in the PT group than the PRP group. However, improvement of the DASH score of the PRP group was significantly better than the PT group. Conclusions: When we compared with PT, PRP seemed to be a well-tolerated application which showed promising results in patients with chronic partial supraspinatus tears. PMID:26473076

  13. Hyperuricemia in Tendons.

    PubMed

    Andia, Isabel; Abate, Michele

    2016-01-01

    Hyperuricemia, particularly gout, and the immune inflammatory response are highly integrated. Both, long standing hyperuricemia and monosodium urate (MSU) crystal deposition can challenge tendon homeostasis because of their potential to cause inflammation to the host. Knowledge is emerging from clinical imaging research depicting where MSU crystals deposit, including patellar tendon, triceps and quadriceps tendons. Remarkably, subclinical tendon inflammation and damage are also present in asymptomatic hyperuricemia. Monosodium urate crystals act as danger activating molecular patterns (DAMPs), activating the inflammasome and inducing the secretion of IL-1beta, a key mediator of the inflammatory response. The crucial role of IL-1beta in driving the inflammatory events during gout attacks is supported by the clinical efficacy of IL-1beta blockade. Some data implicating IL-1beta as an initiator of tendinopathy exist, but the link between hyperuricemia and the development of tendinopathy remains to be validated. Further knowledge about the interactions of uric acid with both innate immune and tendon cells, and their consequences may help to determine if there is a subclass of hyperuricemic-tendinopathy. PMID:27535254

  14. Nonsilver treatment vs. silver sulfadiazine in treatment of partial-thickness burn wounds in children: a systematic review and meta-analysis.

    PubMed

    Rashaan, Zjir M; Krijnen, Pieta; Klamer, Rachel R M; Schipper, Inger B; Dekkers, Olaf M; Breederveld, Roelf S

    2014-01-01

    The evidence for application of silver-containing dressings and topicals in the treatment of partial-thickness burns in pediatric patients is largely based on clinical trials involving adult patients despite the important differences between the skin of children and adults. A systematic review and meta-analysis was performed of all randomized controlled trials comparing nonsilver treatment with silver-containing dressings and silver topical agents in children with partial-thickness burns in the acute stage. Endpoints were wound healing, grafting, infection, pain, number of dressing changes, length of hospital stay, and scarring. Seven randomized controlled trials were included involving 473 participants. All trials used silver sulfadiazine as control in comparison with five different nonsilver treatments. Most trials were of moderate quality with high risk of bias. Use of nonsilver treatment led to shorter wound healing time (weighted mean difference: -3.43 days, 95% confidence interval: -4.78, -2.07), less dressing changes (weighted mean difference: -19.89 dressing changes, 95% confidence interval: -38.12, -1.66), and shorter length of hospital stay (weighted mean difference: -2.07 days, 95% confidence interval: -2.63, -1.50) compared with silver sulfadiazine treatment, but no difference in the incidence of wound infection or grafting was found. In conclusion, nonsilver treatment may be preferred over silver sulfadiazine, but high-quality randomized controlled trials are needed to validly confirm the effectiveness of silver containing preparations, in particular silver-containing dressings, above nonsilver treatments. PMID:24899251

  15. Management of the Acute Partial-thickness Burned Hand; Moist Exposed Burn Ointment or Silver Sulphadiazine Cream both Combined with a Polyethylene Bag

    PubMed Central

    Allam, A.M.; Mostafa, W.; Zayed, E.; El-Gamaly, J.

    2007-01-01

    Summary Hand burns predominantly affect young adults, and therefore have serious social and financial implications. In the present work, 106 patients with less than 25% body surface area burns and acute partial-thickness burned hands were managed using polyethylene bags and 1% local silver sulphadiazine (SSD) cream or moist exposed burn ointment (MEBO). Females made up 61.3% of the cases and flame burn was the majority cause (54.7%). There were no significant differences between the two groups regarding either the analgesic effect after local ointment application or hand movement inside the polyethylene bag. Local agent crustation over the wound was very evident in the hands managed by local 1% SSD cream (69.81%). On follow-up, the burned hands healed faster using local MEBO (10.48 versus 14.53 days), with fewer post-burn hand deformities and better active hand movements; however, the total cost until complete hand burn wound healing was higher with MEBO than with 1% SSD, although the final results were superior, with early return to work, when MEBO was used. We concluded that the use of MEBO as a topical agent and of polyethylene bags for the dressing of the acute partial-thickness burned hand accelerated healing; daily wound evaluation was easy as there was no crustation over it of the agent. It was more expensive than 1% SSD cream but presented fewer post-burn complications and more rapid healing, with shorter hospital stay. PMID:21991086

  16. 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.

  17. Arthroscopic Marginal Resection of a Lipoma of the Supraspinatus Muscle in the Subacromial Space

    PubMed Central

    Pagán Conesa, Alejandro; Aznar, Carlos Verdú; Herrera, Manuel Ruiz; Lopez-Prats, Fernando Anacleto

    2015-01-01

    Subacromial impingement syndrome is a common cause of shoulder pain in young adults and seniors at present. The etiology of this syndrome is associated with several shoulder disorders, most related to aging, overhead activities, and overuse. The subacromial space is well circumscribed and limited in size, and soft-tissue growing lesions, such as tumors, can endanger the normal function of the shoulder girdle. We present a case of shoulder impingement syndrome caused by an intramuscular lipoma of the supraspinatus muscle in the subacromial space in a 50-year-old male bank manager. Radiographs, magnetic resonance imaging, and a computed tomography scan showed a well-circumscribed soft-tissue tumor at the supraspinatus-musculotendinous junction. It was arthroscopically inspected and dissected and complete marginal excision was performed through a conventional augmented anterolateral portal, avoiding the need to open the trapezius fascia or perform an acromial osteotomy. Microscopic study showed a benign lipoma, and the shoulder function of the patient was fully recovered after a rehabilitation period of 4 months. This less invasive technique shows similar results to conventional open surgery. PMID:26759779

  18. Arthroscopic Marginal Resection of a Lipoma of the Supraspinatus Muscle in the Subacromial Space.

    PubMed

    Pagán Conesa, Alejandro; Aznar, Carlos Verdú; Herrera, Manuel Ruiz; Lopez-Prats, Fernando Anacleto

    2015-08-01

    Subacromial impingement syndrome is a common cause of shoulder pain in young adults and seniors at present. The etiology of this syndrome is associated with several shoulder disorders, most related to aging, overhead activities, and overuse. The subacromial space is well circumscribed and limited in size, and soft-tissue growing lesions, such as tumors, can endanger the normal function of the shoulder girdle. We present a case of shoulder impingement syndrome caused by an intramuscular lipoma of the supraspinatus muscle in the subacromial space in a 50-year-old male bank manager. Radiographs, magnetic resonance imaging, and a computed tomography scan showed a well-circumscribed soft-tissue tumor at the supraspinatus-musculotendinous junction. It was arthroscopically inspected and dissected and complete marginal excision was performed through a conventional augmented anterolateral portal, avoiding the need to open the trapezius fascia or perform an acromial osteotomy. Microscopic study showed a benign lipoma, and the shoulder function of the patient was fully recovered after a rehabilitation period of 4 months. This less invasive technique shows similar results to conventional open surgery. PMID:26759779

  19. Is the Supraspinatus Muscle Atrophy Truly Irreversible after Surgical Repair of Rotator Cuff Tears?

    PubMed Central

    Chung, Seok Won; Kim, Sae Hoon; Tae, Suk-Kee; Yoon, Jong Pil; Choi, Jung-Ah

    2013-01-01

    Background Atrophy of rotator cuff muscles has been considered an irreversible phenomenon. The purpose of this study is to evaluate whether atrophy is truly irreversible after rotator cuff repair. Methods We measured supraspinatus muscle atrophy of 191 patients with full-thickness rotator cuff tears on preoperative magnetic resonance imaging and postoperative multidetector computed tomography images, taken at least 1 year after operation. The occupation ratio was calculated using Photoshop CS3 software. We compared the change between pre- and postoperative occupation ratios after modifying the preoperative occupation ratio. In addition, possible relationship between various clinical factors and the change of atrophy, and between the change of atrophy and cuff integrity after surgical repair were evaluated. Results The mean occupation ratio was significantly increased postoperatively from 0.44 ± 0.17 to 0.52 ± 0.17 (p < 0.001). Among 191 patients, 81 (42.4%) showed improvement of atrophy (more than a 10% increase in occupation ratio) and 33 (17.3%) worsening (more than a 10% decrease). Various clinical factors such as age tear size, or initial degree of atrophy did not affect the change of atrophy. However, the change of atrophy was related to repair integrity: cuff healing failure rate of 48.5% (16 of 33) in worsened atrophy; and 22.2% (18 of 81) in improved atrophy (p = 0.007). Conclusions The supraspinatus muscle atrophy as measured by occupation ratio could be improved postoperatively in case of successful cuff repair. PMID:23467404

  20. Posterior Tibial Tendon Transfer.

    PubMed

    Shane, Amber M; Reeves, Christopher L; Cameron, Jordan D; Vazales, Ryan

    2016-01-01

    When performed correctly with the right patient population, a tibialis posterior muscle/tendon transfer is an effective procedure. Many different methods have been established for fixating the tendon, each of which has its' own indications. Passing through the interosseous membrane is the preferred and recommended method and should be used unless this is not possible. Good surgical planning based on patient needs and expectations, along with excellent postoperative care including early range of motion and physical therapy minimizes risk of complications and allows for the optimal outcome to be achieved. PMID:26590722

  1. Tibialis Anterior Tendon Transfer.

    PubMed

    Mulhern, Jennifer L; Protzman, Nicole M; Brigido, Stephen A

    2016-01-01

    Tendon transfer procedures are used commonly for the correction of soft tissue imbalances and instabilities. The complete transfer and the split transfer of the tibialis anterior tendon are well-accepted methods for the treatment of idiopathic equinovarus deformity in children and adults. Throughout the literature, complete and split transfer have been shown to yield significant improvements in ankle and foot range of motion and muscle function. At present, there is insufficient evidence to recommend one procedure over the other, although the split procedure has been advocated for consistently achieving inversion to eversion muscle balance without overcorrection. PMID:26590723

  2. Histomorphometric analysis of early epithelialization and dermal changes in mid-partial-thickness burn wounds in humans treated with porcine small intestinal submucosa and silver-containing hydrofiber.

    PubMed

    Salgado, Rosa M; Bravo, Leonardo; García, Mario; Melchor, Juan M; Krötzsch, Edgar

    2014-01-01

    The objective of this study was to determine the healing rates of mid-partial-thickness burns treated with a porcine intestinal submucosa (SIS) vs. silver-containing cellulose hydrofiber (AgH) dressings. This was done by comparing healing response of burn wounds treated with SIS vs that of burns treated with AgH dressings. Five patients with mid-partial-thickness burns ≤10% of body surface were treated simultaneously, but in different areas, with SIS and AgH dressings; full-thickness biopsies were taken at days 0 and 7. Tissues treated with SIS presented higher epithelial maturation index (6.2 ± 0.84 vs. 3.2 ± 3.28; [mean ± standard deviation], P = .029), better orientation and differentiation of epithelial cells, as well as an appropriate basal lamina structure, collagen deposition, and higher transforming growth factor-β3 expression (7.4 ± 8.1 vs. 2.1 ± 2.6; P = .055) than tissues treated with AgH dressings. Importantly, after the treatment SIS was not integrated in healed tissues. After 3 months of treatment, SIS produced a lower score according to Vancouver Scar Scale (3.6 ± 2.6 vs. 7.2 ± 2.5, P = .025).The submucosa dressing does not simply act as scaffolding for the wound, it provides stimulation in the healing area, probably via growth factors initially present in SIS or matrikines derived from its digestion in the wound site. In conclusion, the present study demonstrated that biological matrices favor the wound-healing process. PMID:24823330

  3. Regulatory Role of Collagen V in Establishing Mechanical Properties of Tendons and Ligaments is Tissue-Dependent

    PubMed Central

    Connizzo, Brianne K.; Freedman, Benjamin R.; Fried, Joanna H.; Sun, Mei; Birk, David E.; Soslowsky, Louis J.

    2015-01-01

    Patients with classic (type I) Ehlers-Danlos Syndrome (EDS), characterized by heterozygous mutations in the Col5a1 and Col5a2 genes, exhibit connective tissue hyperelasticity and recurrent joint dislocations, indicating a potential regulatory role for collagen V in joint stabilizing soft tissues. This study asked whether the contribution of collagen V to the establishment of mechanical properties is tissue-dependent. We mechanically tested four different tissues from wild type and targeted collagen V-null mice: the flexor digitorum longus tendon (FDL), Achilles tendon (ACH), the anterior cruciate ligament (ACL) and the supraspinatus tendon (SST). Area was significantly reduced in the Col5a1ΔTen/ΔTen group in the FDL, ACH, and SST. Maximum load and stiffness were reduced in the Col5a1ΔTen/ΔTen group for all tissues. However, insertion site and midsubstance modulus were reduced only for the ACL and SST. This study provides evidence that the regulatory role of collagen V in extracellular matrix assembly is tissue-dependent and that joint instability in classic EDS may be caused in part by insufficient mechanical properties of the tendons and ligaments surrounding each joint. PMID:25876927

  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. [Diseases of the Achilles tendon].

    PubMed

    Schönbauer, H R

    1986-01-01

    In this report diseases of the Achilles tendon are discussed. First an anatomical survey of this region is presented including anatomical variations together with the results of the author's own investigations on corpses. Certain positions and insertions of the plantaris tendon with respect to the Achilles tendon may have pathological influence. Pathological aspects are discussed after a review of the physiology of the Achilles tendon, including functional and tensile tests. The clinical picture changes according to the location of the pathological disorder--tendon, paratenon, insertion and bursae--and whether the disease is acute or chronic. There are various reasons for degenerative changes in the tendon, which can even lead to rupture. Surgical and non-surgical treatment and their indications are presented. In conclusion treatment methods and their results for 36 cases are given. PMID:3087066

  6. Traumatic flexor tendon injuries.

    PubMed

    Lapegue, F; Andre, A; Brun, C; Bakouche, S; Chiavassa, H; Sans, N; Faruch, M

    2015-12-01

    The flexor system of the fingers consisting of flexor tendons and finger pulleys is a key anatomic structure for the grasping function. Athletes and manual workers are particularly at risk for closed injuries of the flexor system: ruptured pulleys, ruptures of the flexor digitorum profundus from its distal attachment ("jersey finger"), and less frequently, ruptures of the flexor digitorum superficialis and of the lumbrical muscles. Open injuries vary more and their imaging features are more complex since tendons may be torn in several locations, the locations may be unusual, the injuries may be associated with nerve and vascular injuries, fibrosis… Sonography is the best imaging modality to associate with the clinical exam for it allows an experienced physician to make an accurate and early diagnosis, crucial to appropriate early treatment planning. PMID:26564614

  7. Tribological characteristics of healthy tendon.

    PubMed

    Theobald, Peter S; Dowson, Duncan; Khan, Ilyas M; Jones, Michael D

    2012-07-26

    Tendons transfer muscular forces efficiently and painlessly, facilitating joint motion. Whilst the tribology of articular cartilage is constantly explored, a poorer understanding remains of tendon lubrication and friction. This study reports experimental data describing the tribological characteristics of tendon and its surrounding tissue, before presenting an arithmetic solution to facilitate numerical modelling. The experimental characteristics of the tensile (i.e. mid-substance) and compressive (i.e. fibrocartilaginous) regions of bovine flexor tendon were investigated using a pin-on-plate tribometer, with immunofluroscence analysis describing the relative intensity and distribution of surface-bound lubricin. Arithmetic analysis considering the digital extensor tendon determined that, in physiological conditions, the tensile tendon region was able to generate elastohydrodynamic lubrication (EHL). The equivalent region of compressive tendon exhibited a higher intensity of surface-bound lubricin which, it is hypothesised, serves to minimise the increased frictional resistance due to generating only mixed or boundary lubrication regimes. Arithmetic analysis indicates that, given a more favourable biomechanical environment, this region can also generate EHL. Whilst acknowledging the limitations of transferring data from an animal model to a clinical environment, by providing the first data and equations detailing the film thicknesses and lubrication regime for these two tendon regions it is hoped that clinicians, engineers and scientists can consider improved clinical strategies to tackle both tendinopathy and tendon rupture. PMID:22704825

  8. Mechanisms of collagen fibril alignment in tendon injury: from tendon regeneration to artificial tendon.

    PubMed

    Torigoe, Kojun; Tanaka, Hirohito F; Yonenaga, Kazumichi; Ohkochi, Hiroki; Miyasaka, Muneo; Sato, Ryota; Kuzumaki, Toru; Yoshida, Kazuharu; Yoshida, Toshiko

    2011-12-01

    The process by which collagen fibrils are aligned following tendon injury remains unknown. Therefore, we analyzed the process of tendon regeneration by transmission electron microscopy, using a film model method. In mice, the Achilles tendon of medial head was transected. On day 3, after only the proximal end of the transected tendon was placed on film and kept in vivo, a translucent substance containing granules, called tendon gel, was secreted. On day 5, the granules assembled in a loose (L) layer, and coalesced tightly in a dense (D) layer, forming an L-D-L layered pattern. On day 10, granules showed high electron density in H layers, which developed into D-H-D layers on day 13. The distal end was placed on film to face the proximal end. On day 10, the tendon gel showed a D-H-D layer pattern. On day 11, mechanical stress from muscular constriction changed the tendon gel to aligned collagen fibrils (6 ± 2 nm in diameter). Thereafter, the diameter of the fibrils increased. Tendon gel harvested on day 5 or day 10 was pulled manually or by hanging weights (about 0.6 MPa). Aligned collagen fibrils (32 ± 7 nm in diameter) were created by traction using tendon gel harvested on day 10. PMID:21618275

  9. Principles of tendon transfers.

    PubMed

    Coulet, B

    2016-04-01

    Tendon transfers are carried out to restore functional deficits by rerouting the remaining intact muscles. Transfers are highly attractive in the context of hand surgery because of the possibility of restoring the patient's ability to grip. In palsy cases, tendon transfers are only used when a neurological procedure is contraindicated or has failed. The strategy used to restore function follows a common set of principles, no matter the nature of the deficit. The first step is to clearly distinguish between deficient muscles and muscles that could be transferred. Next, the type of palsy will dictate the scope of the program and the complexity of the gripping movements that can be restored. Based on this reasoning, a surgical strategy that matches the means (transferable muscles) with the objectives (functions to restore) will be established and clearly explained to the patient. Every paralyzed hand can be described using three parameters. 1) Deficient segments: wrist, thumb and long fingers; 2) mechanical performance of muscles groups being revived: high energy-wrist extension and finger flexion that require strong transfers with long excursion; low energy-wrist flexion and finger extension movements that are less demanding mechanically, because they can be accomplished through gravity alone in some cases; 3) condition of the two primary motors in the hand: extrinsics (flexors and extensors) and intrinsics (facilitator). No matter the type of palsy, the transfer surgery follows the same technical principles: exposure, release, fixation, tensioning and rehabilitation. By performing an in-depth analysis of each case and by following strict technical principles, tendon transfer surgery leads to reproducible results; this allows the surgeon to establish clear objectives for the patient preoperatively. PMID:27117119

  10. TLP tendon bottom connector

    SciTech Connect

    Owens, H.S.

    1986-09-16

    This patent describes a bottom connector for connecting a tendon segment of a tension leg platform to a subsea template which includes a receptacle for the connector comprising: a first body member adapted to be received within an anchor receptacle, a second body member connected to the first body member through a flexible joint for universally pivotal movement and adapted to be connected to the tendon segment, a latch carrier movable with respect to the first body member and having latch segments pivotally connected to the latch carrier, the latch segments being such that in one position of the latch carrier, the latch segments engage both a recess in the receptacle and the first body member when the connector is inserted into the receptacle a sufficient distance so that the latch segments and carrier will react to the recess and such that when the latch carrier is in another position, the latch segments are clear of the recess to enable the connector to move further into the receptacle or to allow the bottom connector to be removed from the receptacle, and release means operative to maintain the carrier in the other position if a decision is made to remove the connector from the receptacle.

  11. Effect of red and near-infrared wavelengths on low-level laser (light) therapy-induced healing of partial-thickness dermal abrasion in mice.

    PubMed

    Gupta, Asheesh; Dai, Tianhong; Hamblin, Michael R

    2014-01-01

    Low-level laser (light) therapy (LLLT) promotes wound healing, reduces pain and inflammation, and prevents tissue death. Studies have explored the effects of various radiant exposures on the effect of LLLT; however, studies of wavelength dependency in in vivo models are less common. In the present study, the healing effects of LLLT mediated by different wavelengths of light in the red and near-infrared (NIR) wavelength regions (635, 730, 810, and 980 nm) delivered at constant fluence (4 J/cm(2)) and fluence rate (10 mW/cm(2)) were evaluated in a mouse model of partial-thickness dermal abrasion. Wavelengths of 635 and 810 nm were found to be effective in promoting the healing of dermal abrasions. However, treatment using 730- and 980-nm wavelengths showed no sign of stimulated healing. Healing was maximally augmented in mice treated with an 810-nm wavelength, as evidenced by significant wound area reduction (p < 0.05), enhanced collagen accumulation, and complete re-epithelialization as compared to other wavelengths and non-illuminated controls. Significant acceleration of re-epithelialization and cellular proliferation revealed by immunofluorescence staining for cytokeratin-14 and proliferating cell nuclear antigen (p < 0.05) was evident in the 810-nm wavelength compared with other groups. Photobiomodulation mediated by red (635 nm) and NIR (810 nm) light suggests that the biological response of the wound tissue depends on the wavelength employed. The effectiveness of 810-nm wavelength agrees with previous publications and, together with the partial effectiveness of 635 nm and the ineffectiveness of 730 and 980 nm wavelengths, can be explained by the absorption spectrum of cytochrome c oxidase, the candidate mitochondrial chromophore in LLLT. PMID:23619627

  12. Biomechanical Effect of Margin Convergence Techniques: Quantitative Assessment of Supraspinatus Muscle Stiffness.

    PubMed

    Hatta, Taku; Giambini, Hugo; Zhao, Chunfeng; Sperling, John W; Steinmann, Scott P; Itoi, Eiji; An, Kai-Nan

    2016-01-01

    Although the margin convergence (MC) technique has been recognized as an option for rotator cuff repair, little is known about the biomechanical effect on repaired rotator cuff muscle, especially after supplemented footprint repair. The purpose of this study was to assess the passive stiffness changes of the supraspinatus (SSP) muscle after MC techniques using shear wave elastography (SWE). A 30 × 40-mm U-shaped rotator cuff tear was created in 8 cadaveric shoulders. Each specimen was repaired with 6 types of MC technique (1-, 2-, 3-suture MC with/without footprint repair, in a random order) at 30° glenohumeral abduction. Passive stiffness of four anatomical regions in the SSP muscle was measured based on an established SWE method. Data were obtained from the SSP muscle at 0° abduction under 8 different conditions: intact (before making a tear), torn, and postoperative conditions with 6 techniques. MC techniques using 1-, or 2-suture combined with footprint repair showed significantly higher stiffness values than the intact condition. Passive stiffness of the SSP muscle was highest after a 1-suture MC with footprint repair for all regions when compared among all repair procedures. There was no significant difference between the intact condition and a 3-suture MC with footprint repair. MC techniques with single stitch and subsequent footprint repair may have adverse effects on muscle properties and tensile loading on repair, increasing the risk of retear of repairs. Adding more MC stitches could reverse these adverse effects. PMID:27583402

  13. THE COMPARISON OF THE EMPTY CAN AND FULL CAN TECHNIQUES AND A NEW DIAGONAL HORIZONTAL ADDUCTION TEST FOR SUPRASPINATUS MUSCLE TESTING USING CROSS‐SECTIONAL ANALYSIS THROUGH ULTRASONOGRAPHY

    PubMed Central

    White, Douglas M.; Smith, Wayne

    2013-01-01

    Purpose/Background: Several examination tests are currently used for diagnosing a supraspinatus lesion. The empty can (EC) test is currently considered the gold standard for testing, but full can (FC) testing is also utilized. Both of these tests do not fully eliminate the deltoid synergistic when resistance is applied. A new diagonal horizontal adduction (DHA) technique has been developed for evaluation of the supraspinatus that has not yet been compared with the existing techniques (EC/FC). Cross‐sectional analysis (CSA) change during contraction as an ultrasonographic means of visualizing and measuring contraction of the supraspinatus has been reported previously. Objective: The purpose of this study was to use diagnostic musculoskeletal ultrasound (MSK) to compare CSA of the supraspinatus during the FC, EC, and the DHA tests. Methods: The supraspinatus muscle of 37 healthy, uninjured volunteers (21 males and 16 females, mean age of 26.9) were visualized and CSA was captured during 4 randomly assigned test positions (including control) using MSK. Results: A one‐way Analysis of Variance with repeated measures of the mean CSA obtained in the testing positions was performed followed by least significant difference (LSD) for post‐hoc analysis. Significant differences (p < 0.05) were found between the mean CSA of the controls and the CSA of each of the three testing procedures analyzed using the MSK. There were no significant differences (p < 0.05) in CSA between any of the three testing procedures. Conclusions: In this study, MSK visualized and objectified activity of the supraspinatus muscle as evidenced through increased mean CSA when resisted. All the testing positions (FC, EC, and DHA) demonstrated significantly increased mean CSA of the muscle when isometrically contracted when compared to the resting control. The DHA procedure also elicited significant increase in CSA of the supraspinatus. However, no significant difference was found between the CSA of

  14. Partial Tendon Release for Treatment of a Symptomatic Snapping Biceps Femoris Tendon

    PubMed Central

    Crow, Scott A.; Quach, Tony; McAllister, David R.

    2009-01-01

    Snapping of the biceps femoris tendon over the fibular head is an uncommon condition. Reported causes include an anomalous insertion of the tendon, trauma at the insertion site of the tendon, and an abnormality of the fibular head. This article reports a case of a painful snapping biceps femoris tendon in a patient without an anomalous tendon insertion or an abnormality of the fibular head. Partial release of the superior aspect of the tendon resulted in resolution of symptoms. PMID:23015904

  15. 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

  16. 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

  17. Tendon Transfers for Combined Peripheral Nerve Injuries.

    PubMed

    Makarewich, Christopher A; Hutchinson, Douglas T

    2016-08-01

    Combined peripheral nerve injuries present a unique set of challenges to the hand surgeon when considering tendon transfers. They are often associated with severe soft tissue trauma, including lacerations to remaining innervated muscles and tendons, significant scar formation, and substantial sensory loss. In the case of combined nerve injuries, there are typically fewer options for tendon transfers due to fewer tendons of shared function that are expendable as well as associated injuries to tendon or muscle bellies. As such, careful preoperative planning must be performed to make the most of remaining muscle tendon units. PMID:27387081

  18. Extensive Loss of Tibialis Anterior Tendon: Surgical Repair With Split Tendon Transfer of Tibialis Posterior Tendon: A Case Report.

    PubMed

    Miyazaki, Tsuyoshi; Uchida, Kenzo; Kokubo, Yasuo; Inukai, Tomoo; Sakamoto, Takumi; Yamagishi, Atsushi; Kitade, Makoto; Baba, Hisatoshi

    2016-01-01

    Extensive damage of the tibialis anterior tendon is rare and mainly caused by trauma. Surgical treatment of these injuries can become challenging owing to the limited availability of autogenous graft resources for reconstruction of the defect. In the present case report, we describe a large defect in the midfoot soft tissue after a traffic injury, which included complete loss of the tibialis anterior tendon. The tendon was reconstructed by split tendon transfer of the tibialis posterior tendon without sacrificing function, which was confirmed by the follow-up examination at 6 years after injury. We believe split tendon transfer of the tibialis posterior tendon can be one of the treatment options for patients with extensive disruption of the tibialis anterior tendon. PMID:26213163

  19. Achilles tendon rupture rehabilitation

    PubMed Central

    Kearney, R. S.; Parsons, N.; Underwood, M.; Costa, M. L.

    2015-01-01

    Objectives The evidence base to inform the management of Achilles tendon rupture is sparse. The objectives of this research were to establish what current practice is in the United Kingdom and explore clinicians’ views on proposed further research in this area. This study was registered with the ISRCTN (ISRCTN68273773) as part of a larger programme of research. Methods We report an online survey of current practice in the United Kingdom, approved by the British Orthopaedic Foot and Ankle Society and completed by 181 of its members. A total of ten of these respondents were invited for a subsequent one-to-one interview to explore clinician views on proposed further research in this area. Results The survey showed wide variations in practice, with patients being managed in plaster cast alone (13%), plaster cast followed by orthoses management (68%), and orthoses alone (19%). Within these categories, further variation existed regarding the individual rehabilitation facets, such as the length of time worn, the foot position within them and weight-bearing status. The subsequent interviews reflected this clinical uncertainty and the pressing need for definitive research. Conclusions The gap in evidence in this area has resulted in practice in the United Kingdom becoming varied and based on individual opinion. Future high-quality randomised trials on this subject are supported by the clinical community. Cite this article: Bone Joint Res 2015;4:65–9 PMID:25868938

  20. Common Disorders of the Achilles Tendon

    MedlinePlus

    ... stress on the tendon too quickly, leading to micro-injury of the tendon fibers. Due to this ... with over-pronation or gait abnormalities, custom orthotic devices may be prescribed. Night splints. Night splints help ...

  1. Silastic tendon graft: its role in neglected tendon repair.

    PubMed

    LaBarbiera, A P; Solitto, R J

    1990-01-01

    A case history is presented of the repair of a neglected traumatic tendon laceration by the use of a permanent Silastic tendon implant, originally manufactured for hand surgery by a staged procedure. Stage I consists of implantation of the Silastic implant and allowance of a 2- to 3-month period for the production of a pseudosheath. Stage II consists of removal of the implant after using it to guide an auto- or allograft, through the newly formed pseudosheath for attachment to the anastomotic sites. PMID:2258563

  2. Rerouting extensor pollicis longus tendon transfer.

    PubMed

    Colantoni Woodside, Julie; Bindra, Randip R

    2015-04-01

    Following radial nerve palsy, loss of the extensor pollicis longus (EPL), abductor pollicis longus and extensor pollicis brevis tendons results in loss of thumb extension and radial abduction. Multiple tendon transfers are described to address the loss of thumb extension following radial palsy utilizing the palmaris longus or flexor digitorum sublimis transferred to the EPL tendon. Owing to its ulnar vector of pull, the EPL tendon is a secondary adductor of the thumb, and in order to mitigate the tendency for thumb adduction, the EPL tendon is divided at the wrist and brought subcutaneously to the radial side of the wrist for repair to the donor tendon to improve the line of pull for the donor tendon. We describe the use of a technique to reroute the EPL tendon through the first compartment in a retrograde fashion prior to repair with the donor tendon on the radial side of the wrist. The use of the first dorsal compartment provides a pulley to maintain the position of the transfer and to prevent potential bowstringing of the tendon as wrist flexion and thumb extension are attempted. because the repair is performed proximal to the extensor retinaculum, the donor tendon length is not compromised. Because the tendon is redirected through the first dorsal compartment and inserts into the distal phalanx, a single transfer attempts to restores both thumb extension and radial abduction. PMID:25746145

  3. Staged tendon grafts and soft tissue coverage

    PubMed Central

    Elliot, David

    2011-01-01

    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. PMID:22022043

  4. Madelung Deformity and Extensor Tendon Rupture.

    PubMed

    Shahcheraghi, Gholam Hossain; Peyman, Maryam; Mozafarian, Kamran

    2015-07-01

    Extensor tendon rupture in chronic Madelung deformity, as a result of tendon attrition on the dislocated distal ulna, is a rare occurrence. It is, however, seen more often in rheumatoid arthritis. There are few case reports in the English-language literature on this issue. We report a case of multiple tendon ruptures in a previously undiagnosed Madelung deformity. PMID:26161772

  5. 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.

  6. Tibialis Anterior Tendon Transfer for Posterior Tibial Tendon Insufficiency.

    PubMed

    Ramanujam, Crystal L; Stapleton, John J; Zgonis, Thomas

    2016-01-01

    The Cobb procedure is useful for addressing stage 2 posterior tibial tendon dysfunction and is often accompanied by a medial displacement calcaneal osteotomy and/or lateral column lengthening. The Cobb procedure can also be combined with selected medial column arthrodesis and realignment osteotomies along with equinus correction when indicated. PMID:26590721

  7. Tendon Ruptures Associated With Corticosteroid Therapy

    PubMed Central

    Halpern, Alan A.; Horowitz, Bruce G.; Nagel, Donald A.

    1977-01-01

    In five patients, tendon ruptures occurred in association with corticosteroid therapy, either systemic or local infiltration. The chronic nature of the pain in all of these patients suggests that what we often call tendinitis may in fact be early or partial ruptures of tendons. Patients who receive local infiltration of corticosteroids should perhaps be advised of the risk of a ruptured tendon. In addition, particularly when the Achilles tendon is involved, immobilization should be utilized initially for a presumed tendinitis or early rupture, to protect the tendon from further injury. ImagesFigure 1.Figure 2. PMID:919538

  8. 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

  9. Efficacy of Various Analgesics on Shoulder Function and Rotator Cuff Tendon-to-Bone Healing in a Rat (Rattus norvegicus) Model

    PubMed Central

    Caro, Adam C; Tucker, Jennica J; Yannascoli, Sarah M; Dunkman, Andrew A; Thomas, Stephen J; Soslowsky, Louis J

    2014-01-01

    Although relief of postoperative pain is an imperative aspect of animal welfare, analgesics that do not interfere with the scientific goals of the study must be used. Here we compared the efficacy of different analgesic agents by using an established rat model of supraspinatus tendon healing and a novel gait-analysis system. We hypothesized that different analgesic agents would all provide pain relief in this model but would cause differences in tendon-to-bone healing and gait parameters. Buprenorphine, ibuprofen, tramadol–gabapentin, and acetaminophen were compared with a no-analgesia control group. Gait measures (stride length and vertical force) on the operative forelimb differed between the control group and both the buprenorphine (2 and 4 d postsurgery) and ibuprofen (2 d postsurgery) groups. Step length was different in the control group as compared with the tramadol–gabapentin (2 d after surgery), buprenorphine (2 and 4 d after surgery), and ibuprofen (2 d after surgery) groups. Regarding tendon-to-bone healing, the ibuprofen group showed less stiffness at the insertion site; no other differences in tendon-to-bone healing were detected. In summary, the analgesics evaluated were associated with differences in both animal gait and tendon-to-bone healing. This information will be useful for improving the management of postsurgical pain without adversely affecting tissue healing. Given its ability to improve gait without impeding healing, we recommend use of buprenorphine for postsurgical pain management in rats. In addition, our gait-analysis system can be used to evaluate new analgesics. PMID:24602546

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

    PubMed Central

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

    2013-01-01

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

  11. Posterior Tibial Tendon Dysfunction (PTTD)

    MedlinePlus

    ... ACFAS | Información en Español Advanced Search Home » Foot & Ankle Conditions » Posterior Tibial Tendon Dysfunction (PTTD) Text Size ... the arch, and an inward rolling of the ankle. As the condition progresses, the symptoms will change. ...

  12. Hyperuricemic PRP in tendon cells.

    PubMed

    Andia, I; Rubio-Azpeitia, E; Maffulli, N

    2014-01-01

    Platelet-rich plasma (PRP) is injected within tendons to stimulate healing. Metabolic alterations such as the metabolic syndrome, diabetes, or hyperuricemia could hinder the therapeutic effect of PRP. We hypothesise that tendon cells sense high levels of uric acid and this could modify their response to PRP. Tendon cells were treated with allogeneic PRPs for 96 hours. Hyperuricemic PRP did not hinder the proliferative actions of PRP. The gene expression pattern of inflammatory molecules in response to PRP showed absence of IL-1b and COX1 and modest expression of IL6, IL8, COX2, and TGF-b1. IL8 and IL6 proteins were secreted by tendon cells treated with PRP. The synthesis of IL6 and IL8 proteins induced by PRP is decreased significantly in the presence of hyperuricemia (P = 0.017 and P = 0.012, resp.). Concerning extracellular matrix, PRP-treated tendon cells displayed high type-1 collagen, moderate type-3 collagen, decorin, and hyaluronan synthase-2 expression and modest expression of scleraxis. Hyperuricemia modified the expression pattern of extracellular matrix proteins, upregulating COL1 (P = 0.036) and COMP (P = 0.012) and downregulating HAS2 (P = 0.012). Positive correlations between TGF-b1 and type-1 collagen (R = 0.905, P = 0.002) and aggrecan (R = 0.833, P = 0.010) and negative correlations between TGF-b1 and IL6 synthesis (R = -0.857, P = 0.007) and COX2 (R = -0.810, P = 0.015) were found. PMID:25276832

  13. Pectoralis Major Tendon Repair

    PubMed Central

    Cordasco, Frank A.; Degen, Ryan; Mahony, Gregory Thomas; Tsouris, Nicholas

    2016-01-01

    Objectives: Systematic reviews of the literature have identified 365 reported cases of Pectoralis Major Tendon (PMT) injuries. While surgical treatment has demonstrated improved outcomes compared to non-operative treatment, there is still relatively limited data on the functional outcome, return to sport and need for 2nd surgery in athletes following PMT repair. This study comprises the largest series of athletes following PMT repair reported to date. The Objective is to report on the functional outcomes, return to sport and need for 2nd surgery in a consecutive series of PMT tears. Methods: From 2009, 81 patients with PMT tears were enrolled in this prospective series. Baseline evaluation included patient demographics, mechanism of injury, physical examination and PMT specific MRI for confirmation of the diagnosis and analysis of the extent of injury. Each patient underwent surgical repair by the senior author utilizing a previously published surgical technique. Patients were then followed at 2 weeks, 6 weeks, 3 months and 6 months and further follow-up was conducted annually thereafter with functional outcome scores and adduction strength testing. The return to sport and incidence of 2nd surgery data were recorded. This study includes the first 40 athletes to reach the 2-year post-operative period. Results: All athletes were male, with an average age of 34.4 years (range 23-59). The patient cohort consisted of 4 professional NFL players and 36 recreational athletes. Average follow-up duration was 2.5 years (range 2 - 6.0 years). The most common mechanisms of injury occurred during the bench press (n=26) and contact sport participation (n=14). Sixteen injuries were complete avulsions involving both the clavicular and sternocostal heads, while 24 were isolated sternocostal head avulsions. Average pre-injury bench press of 396 lbs (range 170-500 lbs) was restored to 241 lbs post-operatively (range 140-550 lbs). Single Assessment Numeric Evaluation (SANE) scores

  14. Metastatic pleomorphic adenoma to the supraspinatus muscle: a case report and review of a rare aggressive clinical entity

    PubMed Central

    McGarry, James G; Redmond, Maeve; Tuffy, John B; Wilson, Lorraine; Looby, Seamus

    2015-01-01

    We report a case of a 65-year-old female with a recurrent right parotid pleomorphic adenoma (PA) 24 years after initial surgical excision. Positron-emission tomography (PET) and computed tomography (CT) demonstrated an unusual suspicious FDG-avid erosive rim enhancing mass centered in the right supraspinatus muscle. Cytology from CT-guided aspiration of the mass was consistent with a histologically benign PA, and the patient was diagnosed with metastatic pleomorphic adenoma (MPA). The patient later developed diffuse pulmonary metastases and died within 3 months. MPA, although rare, is recognised as a potentially lethal malignant complication of recurrent or longstanding benign PA. As no biochemical or genetic parameters are predictive of malignant change, patients presenting with recurrent PA should be considered for screening for metastatic disease. PMID:26629288

  15. Mechanisms of tendon injury and repair

    PubMed Central

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

    2015-01-01

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

  16. The Effects of Glucocorticoid on Tendon and Tendon Derived Cells.

    PubMed

    Dean, Benjamin John Floyd; Carr, Andrew Jonathan

    2016-01-01

    Glucocorticoids are generally used to relieve pain and/or inflammation in a wide variety of musculoskeletal disorders including osteoarthritis, inflammatory arthritis, tendinopathy and degenerative spine disease. Glucocorticoids reduce tendon derived cell proliferation in vitro and reduce extracellular matrix synthesis both in vitro and in vivo, in particular type I collagen synthesis. Glucocorticoids also appear to result in acute deleterious changes in healthy in vivo tendon including collagen necrosis, collagen disorganisation and inflammatory cell infiltration; while the overall effect of glucocorticoid administration on the mechanical properties of healthy in vivo tendon are generally negative. Overall the existing in vitro and in vivo evidence suggests that glucocorticoids should be used with caution in treating painful tendinopathy. Certainly a real need exists to follow up the long term clinical effects of glucocorticoid in treating tendinopathy, as there is currently a paucity of evidence in this area. However in this context while the short term benefits are clear, glucocorticoids remain a useful treatment option provided they are used in the right patients in sensible moderation. PMID:27535266

  17. Active Achilles tendon kinesitherapy accelerates Achilles tendon repair by promoting neurite regeneration.

    PubMed

    Jielile, Jiasharete; Aibai, Minawa; Sabirhazi, Gulnur; Shawutali, Nuerai; Tangkejie, Wulanbai; Badelhan, Aynaz; Nuerduola, Yeermike; Satewalede, Turde; Buranbai, Darehan; Hunapia, Beicen; Jialihasi, Ayidaer; Bai, Jingping; Kizaibek, Murat

    2012-12-15

    Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon. However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14 weeks, underwent tenotomy followed immediately by Achilles tendon microsurgery to repair the Achilles tendon rupture. The tendon was then immobilized or subjected to postoperative early motion treatment (kinesitherapy). Mass spectrography results showed that after 14 days of motion treatment, 18 protein spots were differentially expressed, among which, 12 were up-regulated, consisting of gelsolin isoform b and neurite growth-related protein collapsing response mediator protein 2. Western blot analysis showed that gelsolin isoform b was up-regulated at days 7-21 of motion treatment. These findings suggest that active Achilles tendon kinesitherapy promotes the neurite regeneration of a ruptured Achilles tendon and gelsolin isoform b can be used as a biomarker for Achilles tendon healing after kinesitherapy. PMID:25317130

  18. Active Achilles tendon kinesitherapy accelerates Achilles tendon repair by promoting neurite regeneration☆

    PubMed Central

    Jielile, Jiasharete; Aibai, Minawa; Sabirhazi, Gulnur; Shawutali, Nuerai; Tangkejie, Wulanbai; Badelhan, Aynaz; Nuerduola, Yeermike; Satewalede, Turde; Buranbai, Darehan; Hunapia, Beicen; Jialihasi, Ayidaer; Bai, Jingping; Kizaibek, Murat

    2012-01-01

    Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon. However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14 weeks, underwent tenotomy followed immediately by Achilles tendon microsurgery to repair the Achilles tendon rupture. The tendon was then immobilized or subjected to postoperative early motion treatment (kinesitherapy). Mass spectrography results showed that after 14 days of motion treatment, 18 protein spots were differentially expressed, among which, 12 were up-regulated, consisting of gelsolin isoform b and neurite growth-related protein collapsing response mediator protein 2. Western blot analysis showed that gelsolin isoform b was up-regulated at days 7–21 of motion treatment. These findings suggest that active Achilles tendon kinesitherapy promotes the neurite regeneration of a ruptured Achilles tendon and gelsolin isoform b can be used as a biomarker for Achilles tendon healing after kinesitherapy. PMID:25317130

  19. Tensile mechanical properties of human forearm tendons.

    PubMed

    Weber, J F; Agur, A M R; Fattah, A Y; Gordon, K D; Oliver, M L

    2015-09-01

    Previous studies of the mechanical properties of tendons in the upper limb have used embalmed specimens or sub-optimal methods of measurement. The aim of this study was to determine the biomechanical properties of all tendons from five fresh frozen cadaveric forearms using updated methodology. The cross-sectional area of tendons was accurately measured using a laser reflectance system. Tensile testing was done in a precision servo-hydraulic device with cryo-clamp fixation. We determined that the cross-sectional area of some tendons is variable and directly influences the calculated material properties; visual estimation of this is unreliable. Data trends illustrate that digital extensor tendons possess the greatest tensile strength and a higher Young's modulus than other tendon types. PMID:25940499

  20. On the mechanical function of tendon.

    PubMed

    Kafka, V; Jírová, J; Smetana, V

    1995-01-01

    A mesoscopic approach is followed for mathematical modelling of the specific deformation properties of tendon. The approach starts from our general concept of modelling mechanical behaviour of heterogeneous media and assumes that the structure of tendon is optimized in such a way that it enables its adjacent muscle to work with a constant performance in the course of increasing loading (acting like a gearbox in a car). The model based on this assumption gives results that are in a very good accordance with observed properties of tendons. Clinical experience reveals that if this function of tendon is violated pathological changes appear in the respective muscle. RELEVANCE: Clarification and mathematical modelling of the mechanical function of tendon is of intellectual interest in its own right, but it is important also for cautioning surgeons against unnecessary violation of this function, and for tissue engineering aspects if tendon must be replaced. PMID:11415531

  1. Dynamic behavior of tendons in random seas

    SciTech Connect

    Niedzwecki, J.M.; Rijken, O.R.; Soemantri, D.S.

    1995-12-31

    The dynamic behavior of large scale (1:55) undistorted models of TLP tendons were investigated. The tendons modeled were for a TLP designed to be deployed in a water depth of 914 m. The tendon motions were studied without the presence of the hull, In the study reported, the tendon models were subjected to three quite different design seas and the single and paired tendon configurations were compared under identical wave conditions. The main objective of this study was to examine the dynamic response of TLP tendons under controlled environmental conditions in order to better quantify the observed dynamic behavior. Underwater video tracking techniques were utilized in the experiments to obtain direct measurement of the inline and transverse displacements. Envelopes characterizing the extreme displacement behavior, spatial variations in response and collision behavior are presented and discussed.

  2. Nutrient pathways of flexor tendons in primates

    SciTech Connect

    Manske, P.R.; Lesker, P.A.

    1982-09-01

    The perfusion and diffusion pathways to the flexor profundus tendons of 40 monkeys were investigated by measuring the uptake of tritiated proline by various tendon segments. In the absence of all vascular connections, the process of diffusion provides nutrients to all areas of flexor tendon and in this study the process of diffusion was greater. The distal segment of tendon was observed to be profused most rapidly. The proximal tendon segment is perfused from both the muscular-tendinous junction and the vinculum longus; vincular segment perfusion is via the vinculum longus vessels alone; central segment perfusion is shared by the vinculum longus and vinculum brevis vasculature. The distal segment uptake is by both the process of diffusion or vinculum brevis perfusion. The osseous attachment at the distal phalanx contributes little to tendon nutrition.

  3. 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. PMID:24414293

  4. Ulnar Nerve Injury after Flexor Tendon Grafting.

    PubMed

    McCleave, Michael John

    2016-10-01

    A 43-year-old female is presented who underwent a two-stage tendon reconstruction and developed a low ulnar nerve palsy postoperatively. Exploration found that the tendon graft was passing through Guyon's canal and that the ulnar nerve was divided. This is a previously unreported complication. The reconstruction is discussed, the literature reviewed and a guide is given on how to identify the correct tissue plane when passing a tendon rod. PMID:27595967

  5. Crucial transcription factors in tendon development and differentiation: their potential for tendon regeneration.

    PubMed

    Liu, Huanhuan; Zhu, Shouan; Zhang, Can; Lu, Ping; Hu, Jiajie; Yin, Zi; Ma, Yue; Chen, Xiao; OuYang, Hongwei

    2014-05-01

    Tendons that connect muscles to bone are often the targets of sports injuries. The currently unsatisfactory state of tendon repair is largely attributable to the limited understanding of basic tendon biology. A number of tendon lineage-related transcription factors have recently been uncovered and provide clues for the better understanding of tendon development. Scleraxis and Mohawk have been identified as critical transcription factors in tendon development and differentiation. Other transcription factors, such as Sox9 and Egr1/2, have also been recently reported to be involved in tendon development. However, the molecular mechanisms and application of these transcription factors remain largely unclear and this prohibits their use in tendon therapy. Here, we systematically review and analyze recent findings and our own data concerning tendon transcription factors and tendon regeneration. Based on these findings, we provide interaction and temporal programming maps of transcription factors, as a basis for future tendon therapy. Finally, we discuss future directions for tendon regeneration with differentiation and trans-differentiation approaches based on transcription factors. PMID:24705622

  6. High axial load termination for TLP tendons

    SciTech Connect

    Salama, M.M.

    1992-03-03

    This patent describes a hollow high axial load termination for a composite tubular tendon. It comprises: a curved hollow termination body open at one end wit a circular opening and connected at the opposite curved end with an elongated hollow member of lesser diameter than the diameter of the circular opening of the termination body, a composite tubular tendon containing axial fibers and helical fibers laid on an inner hollow liner; fibers of the composite tubular tendon extending over and covering the termination body from the abutment with the composite tubular tendon to the elongated member of lesser diameter than the termination body.

  7. Tendon Transfers in the Rheumatoid Hand for Reconstruction.

    PubMed

    O'Sullivan, Michael Brody; Singh, Hardeep; Wolf, Jennifer Moriatis

    2016-08-01

    Long-standing rheumatoid arthritis can result in spontaneous tendon rupture caused by attrition of the tendons. Ruptures of the ulnar-sided extensor tendons, flexor pollicis longus, and the flexor digitorum profundus can be seen. Primary repair of these tendon ruptures is frequently not possible because of delayed presentation and tendon damage by the disease process. Tendon transfers are the preferred method of treatment in patients with rheumatoid arthritis. At surgery, it is critical to address the underlying cause of rupture to prevent future tendon ruptures. Rates of tendon rupture may decrease due to improved medications for rheumatoid arthritis. PMID:27387084

  8. Extracorporeal shock wave therapy for non-calcific supraspinatus tendinitis - 10-year follow-up of a randomized placebo-controlled trial.

    PubMed

    Efe, Turgay; Felgentreff, Markus; Heyse, Thomas J; Stein, Thomas; Timmesfeld, Nina; Schmitt, Jan; Roessler, Philip P

    2014-10-01

    Evidence for the efficacy of extracorporeal shock wave therapy (ESWT) in supraspinatus tendinopathy without calcification is sparse, and therefore this treatment option is often controversial. Patients of a randomized placebo-controlled study to analyze the effects of ESWT on function and pain were revisited 10 years after the initial consultation. The former verum group received 6000 impulses (energy flux density, 0.11 mJ/mm²) in three sessions after local anesthesia between 1999 and 2000. The placebo group had 6000 impulses of a sham ESWT after local anesthesia in the same period. Re-evaluation of the patients included a relative Constant score as well as pain measurements (visual analogue scale) during activity and at rest. No significant changes (p>0.05) in relative Constant scores, pain at rest, or pain during activity could be found after a 10-year follow-up between the placebo and verum groups after ESWT. The treatment of non-calcific supraspinatus tendinopathy with ESWT does not seem to have an effect on function or pain improvement in the long run. The results of the present study cannot advise the use of ESWT in cases of non-calcific supraspinatus tendinopathy. PMID:24728846

  9. Distribution of proteins within different compartments of tendon varies according to tendon type.

    PubMed

    Thorpe, Chavaunne T; Karunaseelan, Kabelan J; Ng Chieng Hin, Jade; Riley, Graham P; Birch, Helen L; Clegg, Peter D; Screen, Hazel R C

    2016-09-01

    Although the predominant function of all tendons is to transfer force from muscle to bone and position the limbs, some tendons additionally function as energy stores, reducing the energetic cost of locomotion. To maximise energy storage and return, energy-storing tendons need to be more extensible and elastic than tendons with a purely positional function. These properties are conferred in part by a specialisation of a specific compartment of the tendon, the interfascicular matrix, which enables sliding and recoil between adjacent fascicles. However, the composition of the interfascicular matrix is poorly characterised and we therefore tested the hypothesis that the distribution of elastin and proteoglycans differs between energy-storing and positional tendons, and that protein distribution varies between the fascicular matrix and the interfascicular matrix, with localisation of elastin and lubricin to the interfascicular matrix. Protein distribution in the energy-storing equine superficial digital flexor tendon and positional common digital extensor tendon was assessed using histology and immunohistochemistry. The results support the hypothesis, demonstrating enrichment of lubricin in the interfascicular matrix in both tendon types, where it is likely to facilitate interfascicular sliding. Elastin was also localised to the interfascicular matrix, specifically in the energy-storing superficial digital flexor tendon, which may account for the greater elasticity of the interfascicular matrix in this tendon. A differential distribution of proteoglycans was identified between tendon types and regions, which may indicate a distinct role for each of these proteins in tendon. These data provide important advances into fully characterising structure-function relationships within tendon. PMID:27113131

  10. Ultrasonographic assessment of the equine palmar tendons

    PubMed Central

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

    2015-01-01

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

  11. Simultaneous and spontaneous bilateral quadriceps tendons rupture.

    PubMed

    Celik, Evrim Coşkun; Ozbaydar, Mehmet; Ofluoglu, Demet; Demircay, Emre

    2012-07-01

    Simultaneous and spontaneous bilateral quadriceps tendon rupture is an uncommon injury that is usually seen in association with multiple medical conditions and some medications. We report a case of simultaneous and spontaneous bilateral quadriceps tendon rupture that may be related to the long-term use of a statin. PMID:22561379

  12. 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.

  13. Augmentation of tendon-to-bone healing.

    PubMed

    Atesok, Kivanc; Fu, Freddie H; Wolf, Megan R; Ochi, Mitsuo; Jazrawi, Laith M; Doral, M Nedim; Lubowitz, James H; Rodeo, Scott A

    2014-03-19

    Tendon-to-bone healing is vital to the ultimate success of the various surgical procedures performed to repair injured tendons. Achieving tendon-to-bone healing that is functionally and biologically similar to native anatomy can be challenging because of the limited regeneration capacity of the tendon-bone interface. Orthopaedic basic-science research strategies aiming to augment tendon-to-bone healing include the use of osteoinductive growth factors, platelet-rich plasma, gene therapy, enveloping the grafts with periosteum, osteoconductive materials, cell-based therapies, biodegradable scaffolds, and biomimetic patches. Low-intensity pulsed ultrasound and extracorporeal shockwave treatment may affect tendon-to-bone healing by means of mechanical forces that stimulate biological cascades at the insertion site. Application of various loading methods and immobilization times influence the stress forces acting on the recently repaired tendon-to-bone attachment, which eventually may change the biological dynamics of the interface. Other approaches, such as the use of coated sutures and interference screws, aim to deliver biological factors while achieving mechanical stability by means of various fixators. Controlled Level-I human trials are required to confirm the promising results from in vitro or animal research studies elucidating the mechanisms underlying tendon-to-bone healing and to translate these results into clinical practice. PMID:24647509

  14. Growth factors in porcine full and partial thickness burn repair. Differing targets and effects of keratinocyte growth factor, platelet-derived growth factor-BB, epidermal growth factor, and neu differentiation factor.

    PubMed Central

    Danilenko, D. M.; Ring, B. D.; Tarpley, J. E.; Morris, B.; Van, G. Y.; Morawiecki, A.; Callahan, W.; Goldenberg, M.; Hershenson, S.; Pierce, G. F.

    1995-01-01

    The topical application of recombinant growth factors such as epidermal growth factor, platelet-derived growth factor-BB homodimer (rPDGF-BB), keratinocyte growth factor (rKGF), and neu differentiation factor has resulted in significant acceleration of healing in several animal models of wound repair. In this study, we established highly reproducible and quantifiable full and deep partial thickness porcine burn models in which burns were escharectomized 4 or 5 days postburn and covered with an occlusive dressing to replicate the standard treatment in human burn patients. We then applied these growth factors to assess their efficacy on several parameters of wound repair: extracellular matrix and granulation tissue production, percent reepithelialization, and new epithelial area. In full thickness burns, only rPDGF-BB and the combination of rPDGF-BB and rKGF induced significant changes in burn repair. rPDGF-BB induced marked extracellular matrix and granulation tissue production (P = 0.013) such that the burn defect was filled within several days of escharectomy, but had no effect on new epithelial area or reepithelialization. The combination of rPDGF-BB and rKGF in full thickness burns resulted in a highly significant increase in extracellular matrix and granulation tissue area (P = 0.0009) and a significant increase in new epithelial area (P = 0.007), but had no effect on reepithelialization. In deep partial thickness burns, rKGF induced the most consistent changes. Daily application of rKGF induced a highly significant increase in new epithelial area (P < 0.0001) but induced only a modest increase in reepithelialization (83.7% rKGF-treated versus 70.2% control; P = 0.016) 12 days postburn. rKGF also doubled the number of fully reepithelialized burns (P = 0.02) at 13 days postburn, at least partially because of marked stimulation of both epidermal and follicular proliferation as assessed by proliferating cell nuclear antigen expression. In situ hybridization for

  15. Ultrasonic evaluation of flood gate tendons

    SciTech Connect

    Thomas, G.; Brown, A.

    1997-10-01

    Our water resources infrastructure is susceptible to aging degradation just like the rest of this country`s infrastructure. A critical component of the water supply system is the flood gate that controls the outflow from dams.Long steel rods called tendons attach these radial gates to the concrete in the dam. The tendons are typically forty feet long and over one inch in diameter. Moisture may seep into the grout around the tendons and cause corrosion. Lawrence Livermore National Laboratory is working with the California Department of Water Resources to develop advanced ultrasonic techniques for nondestructively inspecting their tendons. A unique transducer was designed and fabricated to interrogate the entire tendon. A robust,portable unit was assembled that included a computer controlled data acquisition system and specialized data processing software to analyze the ultrasonic signals. This system was tested on laboratory specimens and is presently being fielded at two dam sites.

  16. Blood supply of the Achilles tendon.

    PubMed

    Ahmed, I M; Lagopoulos, M; McConnell, P; Soames, R W; Sefton, G K

    1998-09-01

    The Achilles tendon is one of the most common sites of injury and rupture as a result of overuse. Evidence suggests that the pathogenesis of rupture could involve the pattern of its blood supply. With use of angiographic and histological techniques, the blood supply of the Achilles tendon was investigated in 12 human cadaveric specimens. Angiography confirmed Mayer's 1916 finding that the blood supply to the tendon is from three areas: the musculotendinous and osseotendinous junctions and the paratenon, with the posterior tibial artery providing the major contribution. However, qualitative and quantitative histological analyses in this study showed that the Achilles tendon has a poor blood supply throughout its length, as determined by the small number of blood vessels per cross-sectional area, which do not in general vary significantly along its length. In light of these findings, it is suggested that poor vascularity may prevent adequate tissue repair following trauma, leading to further weakening of the tendon. PMID:9820283

  17. 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

  18. Secondary repair of flexor tendon injuries.

    PubMed

    Battiston, B; Triolo, P F; Bernardi, A; Artiaco, S; Tos, P

    2013-03-01

    Tendon adhesions or even secondary ruptures causing severe hand functional impairment still represent a frequent complication after repair of flexor tendon injuries. Secondary treatment of these problems includes tenolysis, one or two stages flexor tendons reconstruction by grafts or even the use of tendon prosthesis. The mechanism and severity of injury, the status of the surrounding tissues and injured finger, the presence of associated lesions, the age of the patient, post-operative management, patient motivation and the surgeon's skill, may all have implications in the final outcome of the tendon reconstruction. A correct evaluation of the problem by means of classifications such as the one described by Boyes, may help the surgeon in choosing the appropriate technique. PMID:23347767

  19. Mathematical modeling of ligaments and tendons.

    PubMed

    Woo, S L; Johnson, G A; Smith, B A

    1993-11-01

    Ligaments and tendons serve a variety of important functions in maintaining the structure of the human body. Although abundant literature exists describing experimental investigations of these tissues, mathematical modeling of ligaments and tendons also contributes significantly to understanding their behavior. This paper presents a survey of developments in mathematical modeling of ligaments and tendons over the past 20 years. Mathematical descriptions of ligaments and tendons are identified as either elastic or viscoelastic, and are discussed in chronological order. Elastic models assume that ligaments and tendons do not display time dependent behavior and thus, they focus on describing the nonlinear aspects of their mechanical response. On the other hand, viscoelastic models incorporate time dependent effects into their mathematical description. In particular, two viscoelastic models are discussed in detail; quasi-linear viscoelasticity (QLV), which has been widely used in the past 20 years, and the recently proposed single integral finite strain (SIFS) model. PMID:8302027

  20. 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

  1. 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

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

    PubMed

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

    2014-06-27

    Improving tendon repair using Functional Tissue Engineering (FTE) principles has been the focus of our laboratory over the last decade. Although our primary goals were initially focused only on mechanical outcomes, we are now carefully assessing the biological properties of our tissue-engineered tendon repairs so as to link biological influences with mechanics. However, given the complexities of tendon development and healing, it remains challenging to determine which aspects of tendon biology are the most important to focus on in the context of tissue engineering. To address this problem, we have formalized a strategy to identify, prioritize, and evaluate potential biological success criteria for tendon repair. We have defined numerous biological properties of normal tendon relative to cellular phenotype, extracellular matrix and tissue ultra-structure that we would like to reproduce in our tissue-engineered repairs and prioritized these biological criteria by examining their relative importance during both normal development and natural tendon healing. Here, we propose three specific biological criteria which we believe are essential for normal tendon function: (1) scleraxis-expressing cells; (2) well-organized and axially-aligned collagen fibrils having bimodal diameter distribution; and (3) a specialized tendon-to-bone insertion site. Moving forward, these biological success criteria will be used in conjunction with our already established mechanical success criteria to evaluate the effectiveness of our tissue-engineered tendon repairs. PMID:24200342

  3. Functional Tissue Engineering of Tendon: Establishing Biological Success Criteria for Improving Tendon Repair

    PubMed Central

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

    2013-01-01

    Improving tendon repair using Functional Tissue Engineering (FTE) principles has been the focus of our laboratory over the last decade. Although our primary goals were initially focused only on mechanical outcomes, we are now carefully assessing the biological properties of our tissue-engineered tendon repairs so as to link biological influences with mechanics. However, given the complexities of tendon development and healing, it remains challenging to determine which aspects of tendon biology are the most important to focus on in the context of tissue engineering. To address this problem, we have formalized a strategy to identify, prioritize, and evaluate potential biological success criteria for tendon repair. We have defined numerous biological properties of normal tendon relative to cellular phenotype, extracellular matrix and tissue ultra-structure that we would like to reproduce in our tissue-engineered repairs and prioritized these biological criteria by examining their relative importance during both normal development and natural tendon healing. Here, we propose three specific biological criteria which we believe are essential for normal tendon function: 1) scleraxis-expressing cells; 2) well-organized and axially-aligned collagen fibrils having bimodal diameter distribution; and 3) a specialized tendon-to-bone insertion site. Moving forward, these biological success criteria will be used in conjunction with our already established mechanical success criteria to evaluate the effectiveness of our tissue-engineered tendon repairs. PMID:24200342

  4. Achilles tendon: US diagnosis of pathologic conditions. Work in progress

    SciTech Connect

    Blei, C.L.; Nirschl, R.P.; Grant, E.G.

    1986-06-01

    Twenty-three patients were prospectively examined with ultra-sound (US) for acute or recurrent Achilles tendon symptoms. Three types of pathologic conditions of the Achilles tendon were found: tendinitis/tenosynovitis, acute tendon trauma, and postoperative changes. US appears to enable differentiation of these conditions and to contribute to the diagnosis of a broad range of Achilles tendon disorders.

  5. Tendon rupture associated with simvastatin/ezetimibe therapy.

    PubMed

    Pullatt, Raja C; Gadarla, Mamatha Reddy; Karas, Richard H; Alsheikh-Ali, Alawi A; Thompson, Paul D

    2007-07-01

    A case of spontaneous biceps tendon rupture in a physician during therapy with the combination of simvastatin and ezetimibe (Vytorin) is reported. Rechallenge produced tendinopathy in the contralateral biceps tendon that abated with drug discontinuation. Tendon rupture generally occurs in injured tendons. Physiological repair of an injured tendon requires degradation and remodeling of the extracellular matrix through matrix metalloproteinases (MMPs). Statins are known to inhibit MMPs. It was hypothesized that statins may increase the risk of tendon rupture by altering MMP activity. In conclusion, statins may increase the risk of tendon rupture by altering MMP activity. PMID:17599460

  6. The role of mechanobiology in tendon healing.

    PubMed

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

    2012-02-01

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

  7. Viscoelasticity of Tendons Under Transverse Compression.

    PubMed

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

    2016-10-01

    Tendons are highly anisotropic and also viscoelastic. For understanding and modeling their 3D deformation, information is needed on their viscoelastic response under off-axis loading. A study was made, therefore, of creep and recovery of bovine digital extensor tendons when subjected to transverse compressive stress of up to ca. 100 kPa. Preconditioned tendons were compression tested between glass plates at increasing creep loads. The creep response was anomalous: the relative rate of creep reduced with the increasing stress. Over each ca. 100 s creep period, the transverse creep deformation of each tendon obeyed a power law dependence on time, with the power law exponent falling from ca. 0.18 to an asymptote of ca. 0.058 with the increasing stress. A possible explanation is stress-driven dehydration, as suggested previously for the similar anomalous behavior of ligaments. Recovery after removal of each creep load was also anomalous. Relative residual strain reduced with the increasing creep stress, but this is explicable in terms of the reducing relative rate of creep. When allowance was made for some adhesion occurring naturally between tendon and the glass plates, the results for a given load were consistent with creep and recovery being related through the Boltzmann superposition principle (BSP). The tendon tissue acted as a pressure-sensitive adhesive (PSA) in contact with the glass plates: explicable in terms of the low transverse shear modulus of the tendons. PMID:27496279

  8. 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

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

    PubMed Central

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

    2014-01-01

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

  10. An insight on multiscale tendon modeling in muscle-tendon integrated behavior.

    PubMed

    Maceri, Franco; Marino, Michele; Vairo, Giuseppe

    2012-03-01

    This paper aims to highlight the need for a refined tendon model to reproduce the main mechanical features of the integrated muscle-tendon unit (MTU). Elastic nonlinearities of the tendon, both at the nano and microscale, are modeled by a multiscale approach, accounting for the hierarchical arrangement (from molecules up to the fibers) of the collagen structures within the tissue. This model accounts also for the variation of tendon stiffness due to physical activity. Since the proposed tendon model is based on tissue-structured histology, the training-driven adaptation laws are directly formulated starting from histological evidences. Such a tendon description is integrated into a viscoelastic Hill-type model of the whole MTU. A fixed-end contraction test is numerically simulated, and results based on both linear and nonlinear tendon elastic model are compared. Sound and effective time-histories of muscle contractile force and fiber length are obtained only accounting for tendon elastic nonlinearities, which allow to quantitatively recover some experimental data. Finally, proposed numerical results give clear indications toward a rational explanation of the influence of tendon remodeling induced by physical activity on muscular contractile force. PMID:21739087

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

    PubMed

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

    2014-01-01

    Hand surgeons continue to search for the best surgical flexor tendon repair and treatment of the tendon sheaths and pulleys, and they are attempting to establish postoperative regimens that fit diverse clinical needs. It is the purpose of this report to present the current views, methods, and suggestions of six senior hand surgeons from six different countries - all experienced in tendon repair and reconstruction. Although certainly there is common ground, the report presents provocative views and approaches. The report reflects an update in the views of the committee. We hope that it is helpful to surgeons and therapists in treating flexor tendon injuries. PMID:23962872

  12. Multi-layer electrospun membrane mimicking tendon sheath for prevention of tendon adhesions.

    PubMed

    Jiang, Shichao; Yan, Hede; Fan, Dapeng; Song, Jialin; Fan, Cunyi

    2015-01-01

    Defect of the tendon sheath after tendon injury is a main reason for tendon adhesions, but it is a daunting challenge for the biomimetic substitute of the tendon sheath after injury due to its multi-layer membrane-like structure and complex biologic functions. In this study, a multi-layer membrane with celecoxib-loaded poly(l-lactic acid)-polyethylene glycol (PELA) electrospun fibrous membrane as the outer layer, hyaluronic acid (HA) gel as middle layer, and PELA electrospun fibrous membrane as the inner layer was designed. The anti-adhesion efficacy of this multi-layer membrane was compared with a single-layer use in rabbit flexor digitorum profundus tendon model. The surface morphology showed that both PELA fibers and celecoxib-loaded PELA fibers in multi-layer membrane were uniform in size, randomly arrayed, very porous, and smooth without beads. Multi-layer membrane group had fewer peritendinous adhesions and better gliding than the PELA membrane group and control group in gross and histological observation. The similar mechanical characteristic and collagen expression of tendon repair site in the three groups indicated that the multi-layer membrane did not impair tendon healing. Taken together, our results demonstrated that such a biomimetic multi-layer sheath could be used as a potential strategy in clinics for promoting tendon gliding and preventing adhesion without poor tendon healing. PMID:25822877

  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. PMID:20807720

  14. Heel pain and Achilles tendonitis - aftercare

    MedlinePlus

    ... the length of the tendon when walking or running. Your pain and stiffness might increase in the ... or decrease activities that cause pain, such as running or jumping. Do activities that do not strain ...

  15. Pectoralis Major Tendon Repair Post Surgical Rehabilitation

    PubMed Central

    Prohaska, Dan

    2007-01-01

    Pectoralis major tendon rupture is a rare shoulder injury, most commonly seen in weight lifters. This injury is being seen more regularly due to the increased emphasis on healthy lifestyles. Surgical repair of the pectoralis major tendon rupture has been shown to provide superior outcomes regarding strength return. Thus it appears that surgical repair is the treatment of choice for those wishing to return to competitive or recreational athletic activity. This article describes the history and physical examination process for the athlete with pectoralis tendon major rupture. Surgical vs conservative treatment will be discussed. This manuscript provides post surgical treatment guidelines that can be followed after surgical repair of the pectoralis tendon rupture. PMID:21522200

  16. 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

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

    PubMed

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

    2014-12-01

    This short story of flexor tendon repair aims to illustrate hesitations and wanderings of this surgery. Obviously tendon repair was very early considered, but it developed and diffused rather lately. It became a routine practice only in 20th century. This was due on the one hand, in Occident, to the Galen's dogmatic interdiction, on the other hand, to the repair difficulties of this paradoxical structure. Actually tendon is made of fibroblasts and collagen (sticky substances), and then its only goal is to move. According to this necessity, whatever the used techniques are, gliding is the final purpose. Technical evolutions are illustrated by historical contributions to flexor tendon surgery of several "giants" of hand surgery. PMID:24837978

  18. Structure of the tendon connective tissue.

    PubMed

    Kannus, P

    2000-12-01

    Tendons consist of collagen (mostly type I collagen) and elastin embedded in a proteoglycan-water matrix with collagen accounting for 65-80% and elastin approximately 1-2% of the dry mass of the tendon. These elements are produced by tenoblasts and tenocytes, which are the elongated fibroblasts and fibrocytes that lie between the collagen fibers, and are organized in a complex hierarchical scheme to form the tendon proper. Soluble tropocollagen molecules form cross-links to create insoluble collagen molecules which then aggregate progressively into microfibrils and then into electronmicroscopically clearly visible units, the collagen fibrils. A bunch of collagen fibrils forms a collagen fiber, which is the basic unit of a tendon. A fine sheath of connective tissue called endotenon invests each collagen fiber and binds fibers together. A bunch of collagen fibers forms a primary fiber bundle, and a group of primary fiber bundles forms a secondary fiber bundle. A group of secondary fiber bundles, in turn, forms a tertiary bundle, and the tertiary bundles make up the tendon. The entire tendon is surrounded by a fine connective tissue sheath called epitenon. The three-dimensional ultrastructure of tendon fibers and fiber bundles is complex. Within one collagen fiber, the fibrils are oriented not only longitudinally but also transversely and horizontally. The longitudinal fibers do not run only parallel but also cross each other, forming spirals. Some of the individual fibrils and fibril groups form spiral-type plaits. The basic function of the tendon is to transmit the force created by the muscle to the bone, and, in this way, make joint movement possible. The complex macro- and microstructure of tendons and tendon fibers make this possible. During various phases of movements, the tendons are exposed not only to longitudinal but also to transversal and rotational forces. In addition, they must be prepared to withstand direct contusions and pressures. The above

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

    PubMed

    Amlang, M H; Zwipp, H

    2012-02-01

    Tendinosis of the Achilles tendon is a degenerative-reparative structural change of the tendon with microdefects, increases in cross-section due to cicatricial tendon regeneration, neoangiogenesis and reduction of elasticity. The previously used term tendinitis is only rarely used for the chronic form since signs of inflammation such as redness and hyperthermia or elevated levels of inflammatory parameters on laboratory testing are generally absent. Duplex sonography with visualization of the neovascularization has become a valuable supplement not only for diagnostics but also for therapy planning. The classic, conservative therapy for painful tendinosis consists of oral anti-inflammatory drugs, pain-adapted load reduction, raising the heel, stretching the calf musculature, and various physiotherapeutic interventions. When conservative treatment over a period of 4 - 6 months fails to produce any or non-adequate pain relief, an indication for surgical treatment should be considered. In the therapy for fresh ruptures of the Achilles tendon further developments in minimally invasive techniques have led to a worldwide paradigm change over the past 10 years. The decisive advantage of minimally invasive surgical techniques is the lower risk of wound infection as compared to the sutures of the open technique. When compared with conservative functional therapy the minimally invasive repair has the advantage of being less dependent on the compliance of the patient since, in the early phase of tendon healing the suture prevents a separation of the tendon ends upon controlled movements. However, not every patient with a ruptured Achilles tendon should be treated with a minimally invasive repair. Open tendon reconstruction and functional conservative therapy are still justified when the correct indication is given. PMID:22344862

  20. Dynamic ultrasound of peroneal tendon instability.

    PubMed

    Pesquer, Lionel; Guillo, Stéphane; Poussange, Nicolas; Pele, Eric; Meyer, Philippe; Dallaudière, Benjamin

    2016-07-01

    Ankle snapping may be caused by peroneal tendon instability. Anterior instability occurs after traumatic superior peroneal retinaculum injury, whereas peroneal tendon intrasheath subluxation is atraumatic. Whereas subluxation is mainly dynamic, ultrasound allows for the diagnosis and classification of peroneal instability because it allows for real-time exploration. The purpose of this review is to describe the anatomic and physiologic bases for peroneal instability and to heighten the role of dynamic ultrasound in the diagnosis of snapping. PMID:26943704

  1. Grasp Assist Device with Shared Tendon Actuator Assembly

    NASA Technical Reports Server (NTRS)

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

    2015-01-01

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

  2. 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.

  3. Acute Patellar Tendon Rupture after Total Knee Arthroplasty Revision

    PubMed Central

    Rhee, Seung Joon; Pham, The Hien

    2015-01-01

    Patellar tendon rupture is a catastrophic complication following total knee arthroplasty (TKA). Though revision TKA has been suspected of being a predisposing factor for the occurrence of patellar tendon rupture, there are few reports on patellar tendon rupture after revision TKA. Here, we present a case of acute patellar tendon rupture that occurred after TKA revision. In the patient, the patellar tendon was so thin and could not be repaired, and accordingly was sutured end to end. We used the anterior tibialis tendon allograft to augment the poor quality patellar tendon tissue. Fixation of the allograft was done by using the bone tunnel created through tibial tuberosity and suturing the allograft to the patellar tendon and quadriceps tendon. The patient was instructed to wear a full extension knee splint and was kept non-weight bearing for 6 weeks after operation. Full knee extension could be achieved 6 weeks postoperatively. PMID:26060612

  4. 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

  5. The cell biology of suturing tendons.

    PubMed

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

    2010-07-01

    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 12h. 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

  6. 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

  7. Shear Load Transfer in High and Low Stress Tendons

    PubMed Central

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

    2016-01-01

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

  8. Achilles tendon disorders in runners--a review.

    PubMed

    Smart, G W; Taunton, J E; Clement, D B

    1980-01-01

    The Achilles tendon and the classification, etiology, diagnosis, treatment, and management of Achilles tendon disorders in runners are reviewed. Due to the presence of a paratenon sheath, the classification of Achilles tendon disease should be revised. Several etiological mechanisms have been proposed in Achilles tendon disease. The authors recognize: faulty foot biomechanics; poor lower leg flexibility; poorly designed athletic footwear; training surfaces; training intensity; overuse through excessive mileage; inactivity; local steroid injections; rheumatic conditions; and indirect violence. An accurate, thorough differential diagnosis is essential when the athlete presents with an Achilles tendon disorder. Except in total rupture and in extensive partial rupture, the authors do not recommend cast immobilization in the treatment of Achilles tendon disease. When the athlete presents with total rupture of the Achilles tendon, the authors believe that surgical repair is the treatment method of choice. Rehabilitation programs to follow successful treatment of Achilles tendon disease are also presented. PMID:6999281

  9. 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. PMID:26921066

  10. 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.

  11. Modelling approaches for evaluating multiscale tendon mechanics.

    PubMed

    Fang, Fei; Lake, Spencer P

    2016-02-01

    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

  12. 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

  13. Vascular changes in the ruptured Achilles tendon and paratenon.

    PubMed

    Kvist, M; Józsa, L; Järvinen, M

    1992-01-01

    Thirty patients with ruptures of the Achilles tendon were studied. There were 21 men and 9 women with an average age of 36 years. Specimens from the tendon and paratenon in 24 were examined histologically. Tissue samples of 20 were studied by electron microscopy. Marked degenerative, obliterative and/or inflammatory vascular changes were found in all the ruptured tendons and their paratenon. Our findings indicate that poor vascularity play a role in the aetiology of rupture of the Achilles tendon. PMID:1473893

  14. 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

  15. 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

  16. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  17. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) 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...

  18. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) 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...

  19. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) 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...

  20. 21 CFR 888.3025 - Passive tendon prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) 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...

  1. Effect of pulley excision on flexor tendon biomechanics.

    PubMed

    Peterson, W W; Manske, P R; Bollinger, B A; Lesker, P A; McCarthy, J A

    1986-01-01

    Flexor tendon function following excision of various portions of the fibro-osseous pulley system was measured biomechanically using a tensile testing machine. The biomechanical parameters measured were tendon excursion (the excursion of the tendon required to fully flex the digit) and work of flexion (the area under the force-excursion curve, representing all the forces that resist tendon flexion). In this experiment, work of flexion included the forces necessary to accomplish full digital flexion against a 15-g counter-weight, as well as the frictional forces that resist tendon gliding. The results indicate that the work of flexion was affected to a greater degree by pulley loss than was tendon excursion, suggesting that it is a more sensitive measurement of tendon function. A2 was found to be the single most important pulley for flexor tendon function, followed by A4. However, both A2 and A4 had to be present if near-normal hand function was to be achieved; sacrificing the A1 pulley was not associated with a significant loss of flexion. The "pulley effect" of the skin and soft tissue as a supplement to the fibro-osseous pulleys in reducing tendon bow-stringing was also noted. Although the parameters of tendon excursion and work of flexion were used in this study to determine the effect of pulley loss on tendon function, they can also be used to evaluate other flexor tendon studies, such as pulley reconstruction. PMID:3950813

  2. 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

  3. Ultrasonic properties of tendon: velocity, attenuation, and backscattering in equine digital flexor tendons.

    PubMed

    Miles, C A

    1996-05-01

    Ultrasound velocity, attenuation, and backscattering were measured in vitro in samples of equine digital flexor tendon sandwiched between plane, parallel rexolite buffer rods. The buffer rods were coupled to transmitting and receiving transducers (nominally 10 MHz) mounted in-line and facing one another on the jaws of a digital caliper. Six superficial digital flexor (SDF) tendons and six deep digital flexor (DDF) tendons were measured in three orthogonal directions: along the long axis of the tendon (D), and across the tendon in the dorsal-volar (C), and lateral (L) directions. Substantial anisotropy was apparent in all the measured properties. The velocity data, which in both tendons showed a higher velocity along the fibers than across (e.g., in the DDF tendon at 0 degrees C: 1713 +/- 9 m/s in the D direction compared with 1650 +/- 5 m/s in the C direction), were consistent with a composite comprising stiff fibers embedded in a less stiff medium of lower speed. The apparent backscattering coefficient adjusted for the tissue's frequency-dependent attenuation (e.g., in the C direction of the DDF tendon at 0 degrees C: 7.4 x 10(-3) cm-1 sr-1), was independent of frequency in both transverse directions and larger than that measured along the long axis of the tendon (e.g., in DDF tendon at 0 degrees C: 1.2 x 10(-3) cm-1 sr-1 at 7 MHz) in which direction the apparent backscattering coefficient increased with frequency as f4.0 +/- 1.2. The frequency-independent backscattering was thought to be due to specular reflection from the boundaries between the fascicles, i.e., the bundles of fibers making up the tendon, while backscattering along the axis was due to structures of unknown origin, but of a size much smaller than 45 microns. Attenuation of ultrasound directed along the fibers was higher than that across (at 7 MHz in DDF tendon at 0 degrees C: 58 dB/cm in the D direction compared with 11.3 dB/cm in the C direction). Calculations indicated that the attenuation was

  4. Tendon and ligament injuries: the genetic component

    PubMed Central

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

    2007-01-01

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

  5. [Isolated injury of the subscapular muscle tendon].

    PubMed

    Thielemann, F W; Kley, U; Holz, U

    1992-03-01

    Avulsion of the subscapularis tendon is caused by a combined abduction and external rotation trauma of the upper limb. Weakness of internal rotation and a positive apprehension test are clinical signs of the injury. A fracture of the lesser tuberosity in the x-ray film or a disruption of the subscapularis tendon documented in dynamic sonography of the shoulder clarify the diagnosis. Operative treatment is indicated of prevent weakness of internal rotation as well as anterior instability. This recommendation is supported by four cases with full range of motion and good anterior stability after surgery. PMID:1585252

  6. A new device for flexor tendon injuries.

    PubMed

    Dymarczyk, M

    2001-01-01

    Managing the treatment of patients with zone II flexor tendon injuries for successful outcomes has always been a challenge for the hand therapist. Working closely with the patient to help ensure follow-through with the protocol is frequently necessary. If a patient is compliant, the therapist's concern then becomes one of "scar wars" (to use a phrase coined by Ken Flowers). Early active range of motion and tendon gliding are critical parts of most programs. This author has developed a new idea in conjunction with the Indiana Hand Center protocol. PMID:11511017

  7. [Comprehensive treatment in Achilles tendon rupture].

    PubMed

    Matus-Jiménez, Juan; Avalos, Cecilia Henríquez

    2007-01-01

    Due to incapacity caused by calcaneal tendon injuries for the reintegration of patients back to their daily activities and/or sparts it is necessary to decrease the time of reinstatement of patients. At present these times have improved by a good surgical technique and an early rehabilitation, and the patient is returned quickly as he sees less disability. It is proposed in this paper a type of surgical treatment and an early rehabilitation program, which have shortened the time of disability and incorporation to their daily activities and sports to eight weeks in 10 patients with Achilles tendon plasty. PMID:18159917

  8. An unusual cause of Achilles tendon xanthoma.

    PubMed

    Parente, Fabienne; Vesnaver, Matthew; Massie, Rami; Baass, Alexis

    2016-01-01

    Tendinous xanthomas are often thought to be pathognomonic for familial hypercholesterolemia. In this report, we present the case of a young man with a normal lipid profile and Achilles tendon xanthoma. Biochemical and genetic studies confirmed the diagnosis of cerebrotendinous xanthomatosis in this patient. Cerebrotendinous xanthomatosis is a rare autosomal recessive disease associated with xanthoma in tendons and the brain as well as progressive neurologic deficits. Unfortunately, this rare form of reversible dementia is thought to be underdiagnosed. Early diagnosis and treatment of this disease with chenodeoxycholic acid is essential and has been shown to greatly improve the patient's symptoms and prognosis. PMID:27578138

  9. Spontaneous Achilles tendon rupture in alkaptonuria

    PubMed Central

    Alajoulin, Omar A.; Alsbou, Mohammed S.; Ja’afreh, Somayya O.; Kalbouneh, Heba M.

    2015-01-01

    Alkaptonuria (AKU) is a rare inborn metabolic disease characterized by accumulation of homogentisic acid (HGA). Excretion of HGA in urine causes darkening of urine and its deposition in connective tissues causes dark pigmentation (ochronosis), early degeneration of articular cartilage, weakening of the tendons, and subsequent rupture. In this case report, we present a rare case of a patient presented with unilateral spontaneous rupture of Achilles tendon due to AKU. The patient developed most of the orthopedic manifestations of the disease earlier than typical presentations. Alkaptonuria patients should avoid strenuous exercises and foot straining especially in patients developing early orthopedic manifestations. PMID:26620992

  10. 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

  11. 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. PMID:15178003

  12. A Rare Case of Simultaneous Acute Bilateral Quadriceps Tendon Rupture and Unilateral Achilles Tendon Rupture

    PubMed Central

    Leong, Wei Yee; Gheorghiu, Daniel; Rao, Janardhan

    2013-01-01

    Introduction: There have been multiple reported cases of bilateral quadriceps tendon ruptures (QTR) in the literature. These injuries frequently associated with delayed diagnosis, which results in delayed surgical treatment. In very unusual cases, bilateral QTRs can be associated with other simultaneous tendon ruptures. Case Report: We present a rare case of bilateral QTR with a simultaneous Achilles Tendon Rupture involving a 31 years old Caucasian man who is a semi-professional body builder taking anabolic steroids. To date bilateral QTR with additional TA rupture has only been reported once in the literature and to our knowledge this is the first reported case of bilateral QTR and simultaneous TA rupture in a young, fit and healthy individual. Conclusion: The diagnosis of bilateral QTR alone can sometimes be challenging and the possibility of even further tendon injuries should be carefully assessed. A delay in diagnosis could result in delay in treatment and potentially worse outcome for the patient. PMID:27298913

  13. Tendon Injuries of the Hand in Kirikkale, Turkey

    PubMed Central

    Sari, Elif

    2016-01-01

    BACKGROUND Tendon injuries are one of the most common injuries of the hand and challenging problems in trauma surgery. They usually require surgical repair and unlike the single tendon injuries, flexor tendon injuries have higher morbidities when accompanied with nerve injuries. In the present study, I aimed to report the clinical experiences and outcomes about tendon injuries. METHODS A total of 180 patients (149 males, 31 females) between 17 and 56 years old were operated in the clinic due to tendon injury. Seventy isolated extensor tendon injuries, 60 isolated flexor tendon injuries, 30 multiple flexor tendon and major nerve injuries, 18 combined extensor and flexor tendon injuries, and 2 combined extensor, flexor and major nerve injuries were treated. All patients were admitted to the clinic in acute phase and operated immediately. Physiotherapy was started in the third day of the operation. RESULTS Patients were followed up between 6 and 18 months (mean 12.4 months). There was not any major complications except one female patient (0.5%) who did not conform to the treatment protocol after flexor tendon injury. Fifteen patients (8.5%) had poor flexor range of motion. The other patients were healed uneventfully. CONCLUSION Tendon healing may cause some complications from mild to severe degrees. However, atraumatic surgery and a comprehensive postoperative early physiotherapy could decrease these complication rates.

  14. Bilateral patellar tendon rupture associated with statin use.

    PubMed

    Kearns, Marie C; Singh, Vinay K

    2016-01-01

    Patellar tendon rupture is an uncommon clinical presentation, which generally affects the under 40s who are active in sport. Bilateral rupture of both tendons is much rarer. It occurs most frequently in patients with predisposing factors such as corticosteroid use or systemic diseases. The authors present the case of a 56-year-old male on long-term statin therapy who sustained this injury following a fall on ice. He had no known risk factors for tendon rupture. Surgical treatment involved tendon repair using Krakow suture via bony tunnels in the patella. Statins have previously been associated with tendon ruptures at other sites but there have been no published cases of bilateral patellar tendon rupture linked to statin use. We review the literature regarding the association between statins and tendon rupture. PMID:27165749

  15. Bilateral patellar tendon rupture associated with statin use

    PubMed Central

    Kearns, Marie C.; Singh, Vinay K.

    2016-01-01

    Patellar tendon rupture is an uncommon clinical presentation, which generally affects the under 40s who are active in sport. Bilateral rupture of both tendons is much rarer. It occurs most frequently in patients with predisposing factors such as corticosteroid use or systemic diseases. The authors present the case of a 56-year-old male on long-term statin therapy who sustained this injury following a fall on ice. He had no known risk factors for tendon rupture. Surgical treatment involved tendon repair using Krakow suture via bony tunnels in the patella. Statins have previously been associated with tendon ruptures at other sites but there have been no published cases of bilateral patellar tendon rupture linked to statin use. We review the literature regarding the association between statins and tendon rupture. PMID:27165749

  16. Anatomical heterogeneity of tendon: Fascicular and interfascicular tendon compartments have distinct proteomic composition

    PubMed Central

    Thorpe, Chavaunne T.; Peffers, Mandy J.; Simpson, Deborah; Halliwell, Elizabeth; Screen, Hazel R. C.; Clegg, Peter D.

    2016-01-01

    Tendon is a simple aligned fibre composite, consisting of collagen-rich fascicles surrounded by a softer interfascicular matrix (IFM). The composition and interactions between these material phases are fundamental in ensuring tissue mechanics meet functional requirements. However the IFM is poorly defined, therefore tendon structure-function relationships are incompletely understood. We hypothesised that the IFM has a more complex proteome, with faster turnover than the fascicular matrix (FM). Using laser-capture microdissection and mass spectrometry, we demonstrate that the IFM contains more proteins, and that many proteins show differential abundance between matrix phases. The IFM contained more protein fragments (neopeptides), indicating greater matrix degradation in this compartment, which may act to maintain healthy tendon structure. Protein abundance did not alter with ageing, but neopeptide numbers decreased in the aged IFM, indicating decreased turnover which may contribute to age-related tendon injury. These data provide important insights into how differences in tendon composition and turnover contribute to tendon structure-function relationships and the effects of ageing. PMID:26842662

  17. In vitro fatigue of human tendons.

    PubMed

    Schechtman, H; Bader, D L

    1997-08-01

    The purpose of this study was to determine the fatigue behaviour of human tendons in vitro. The testing was accomplished with the use of specially designed grips and the local measurement of tendon cross-sectional area. Ninety specimens prepared from Extensor digitorum longus (EDL) tendons of the foot were subjected to a cyclic square tension-tension stress waveform at physiological frequencies. The maximum tensile stress was normalised to values corresponding to prescribed levels between 10% and 90% of the calculated ultimate tensile strength (UTS) of 100 MPa. The minimum stress was set at 1% of the UTS. A replication of 10 specimens per stress level allowed the use of statistical models for the distribution of fatigue life. Results followed a linear model, of form S = 101.3 - 14.8 log(N), relating the normalised stress to the median number of cycles to failure, therefore suggesting the absence of an endurance limit. The Weibull distribution was found to describe adequately the probability of failure at each stress level. A model which takes into account in vivo healing was proposed. This model was able to explain the presence of intact tendons throughout the lifetime of an individual. PMID:9239568

  18. Minimally Invasive Approach to Achilles Tendon Pathology.

    PubMed

    Hegewald, Kenneth W; Doyle, Matthew D; Todd, Nicholas W; Rush, Shannon M

    2016-01-01

    Many surgical procedures have been described for Achilles tendon pathology; however, no overwhelming consensus has been reached for surgical treatment. Open repair using a central or paramedian incision allows excellent visualization for end-to-end anastomosis in the case of a complete rupture and detachment and reattachment for insertional pathologies. Postoperative wound dehiscence and infection in the Achilles tendon have considerable deleterious effects on overall functional recovery and outcome and sometimes require plastic surgery techniques to achieve coverage. With the aim of avoiding such complications, foot and ankle surgeons have studied less invasive techniques for repair. We describe a percutaneous approach to Achilles tendinopathy using a modification of the Bunnell suture weave technique combined with the use of interference screws. No direct end-to-end repair of the tendon is performed, rather, the proximal stump is brought in direct proximity of the distal stump, preventing overlengthening and proximal stump retraction. This technique also reduces the suture creep often seen with end-to-end tendon repair by providing a direct, rigid suture to bone interface. We have used the new technique to minimize dissection and exposure while restoring function and accelerating recovery postoperatively. PMID:26385574

  19. Achilles Tendon Repair, A Modified Technique

    PubMed Central

    Keyhani, Sohrab; Mardani-Kivi, Mohsen; Abbasian, Mohammadreza; Emami-Moghaddam Tehrani, Mohammad; Lahiji, Farivar Abdollahzadeh

    2013-01-01

    Background: Wound complications following open repair for acute Achilles tendon ruptures (AATR) remain the subject of significant debate. The aim of this study is to investigate the effects of covering repaired AATR using well-nourished connective tissues (paratenon and deep fascia) to avoid complications after open repair. Methods: In this case series study, open repair was performed for 32 active young patients with AATR. After the tendon was repaired, the deep fascia and paratenon was used to cover the Achilles tendon. Patients were followed for two years and any wound complication was recorded. During the last visit, the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot score was completed for all patients. Calf circumference and ankle range of motion were measured and compared with the contralateral side. Patients were asked about returning to previous sports activities and limitations with footwear. Results: Only, one patient developed deep wound infection (3%). None of the patients had any discomfort around the operation area, limitation with footwear, sural nerve injury, re-rupture, and skin adhesion. The AOFAS score averaged 92.5±6. Two patients (7%) were unable to return to previous sports activities because of moderate pain in heavy physical exercises. The calf circumference and ankle ROM were similar between healthy and operated sides. Conclusion: The present study showed that fascial envelope for full covering of the repaired Achilles tendon may help to prevent the occurrence of wound complications. PMID:25207295

  20. On muscle, tendon and high heels.

    PubMed

    Csapo, R; Maganaris, C N; Seynnes, O R; Narici, M V

    2010-08-01

    Wearing high heels (HH) places the calf muscle-tendon unit (MTU) in a shortened position. As muscles and tendons are highly malleable tissues, chronic use of HH might induce structural and functional changes in the calf MTU. To test this hypothesis, 11 women regularly wearing HH and a control group of 9 women were recruited. Gastrocnemius medialis (GM) fascicle length, pennation angle and physiological cross-sectional area (PCSA), the Achilles' tendon (AT) length, cross-sectional area (CSA) and mechanical properties, and the plantarflexion torque-angle and torque-velocity relationships were assessed in both groups. Shorter GM fascicle lengths were observed in the HH group (49.6+/-5.7 mm vs 56.0+/-7.7 mm), resulting in greater tendon-to-fascicle length ratios. Also, because of greater AT CSA, AT stiffness was higher in the HH group (136.2+/-26.5 N mm(-1) vs 111.3+/-20.2 N mm(-1)). However, no differences in the GM PCSA to AT CSA ratio, torque-angle and torque-velocity relationships were found. We conclude that long-term use of high-heeled shoes induces shortening of the GM muscle fascicles and increases AT stiffness, reducing the ankle's active range of motion. Functionally, these two phenomena seem to counteract each other since no significant differences in static or dynamic torques were observed. PMID:20639419

  1. 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. PMID:25919320

  2. A new strategy for the decellularisation of large equine tendons as biocompatible tendon substitutes.

    PubMed

    Bottagisio, M; Pellegata, A F; Boschetti, F; Ferroni, M; Moretti, M; Lovati, A B

    2016-01-01

    Tendon ruptures and/or large losses remain to be a great clinical challenge and often require full replacement of the damaged tissue. The use of auto- and allografts or engineered scaffolds is an established approach to restore severe tendon injuries. However, these grafts are commonly related to scarce biocompatibility, site morbidity, chronic inflammation and poor biomechanical properties. Recently, the decellularisation techniques of allo- or xenografts using specific detergents have been studied and have been found to generate biocompatible substitutes that resemble the native tissue. This study aims to identify a novel decellularisation protocol for large equine tendons that would produce an extracellular matrix scaffold suitable for the regeneration of injured tendons in humans. Specifically, equine tendons were treated either with tri (n-butyl) phosphate alone, or associated to multiple concentrations of peracetic acid (1, 3 and 5 %), which has never before been tested in vitro.Samples were then analysed by histology and with biochemical, biomechanical, and cytotoxicity tests. The best decellularisation protocol, resulting from these examinations, was selected and the chosen scaffold was re-seeded with murine fibroblasts. Resulting grafts were tested for cell viability, histologic analysis, DNA and collagen content. The results identified 1 % tri (n-butyl) phosphate combined with 3 % peracetic acid as the most suitable decellularised matrix in terms of biochemical and biomechanical properties. Moreover, the non-cytotoxic nature of the decellularised matrix allowed for good fibroblast reseeding, thus demonstrating a biocompatible matrix that will be suitable for tendon tissue engineering and hopefully as substitutes in severe tendon damages. PMID:27386840

  3. 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

  4. EGR1 and EGR2 involvement in vertebrate tendon differentiation.

    PubMed

    Lejard, Véronique; Blais, Frédéric; Guerquin, Marie-Justine; Bonnet, Aline; Bonnin, Marie-Ange; Havis, Emmanuelle; Malbouyres, Maryline; Bidaud, Christelle Bonod; Maro, Géraldine; Gilardi-Hebenstreit, Pascale; Rossert, Jérome; Ruggiero, Florence; Duprez, Delphine

    2011-02-18

    The molecules involved in vertebrate tendon formation during development remain largely unknown. To date, only two DNA-binding proteins have been identified as being involved in vertebrate tendon formation, the basic helix-loop-helix transcription factor Scleraxis and, recently, the Mohawk homeobox gene. We investigated the involvement of the early growth response transcription factors Egr1 and Egr2 in vertebrate tendon formation. We established that Egr1 and Egr2 expression in tendon cells was correlated with the increase of collagen expression during tendon cell differentiation in embryonic limbs. Vertebrate tendon differentiation relies on a muscle-derived FGF (fibroblast growth factor) signal. FGF4 was able to activate the expression of Egr genes and that of the tendon-associated collagens in chick limbs. Egr gene misexpression experiments using the chick model allowed us to establish that either Egr gene has the ability to induce de novo expression of the reference tendon marker scleraxis, the main tendon collagen Col1a1, and other tendon-associated collagens Col3a1, Col5a1, Col12a1, and Col14a1. Mouse mutants for Egr1 or Egr2 displayed reduced amounts of Col1a1 transcripts and a decrease in the number of collagen fibrils in embryonic tendons. Moreover, EGR1 and EGR2 trans-activated the mouse Col1a1 proximal promoter and were recruited to the tendon regulatory regions of this promoter. These results identify EGRs as novel DNA-binding proteins involved in vertebrate tendon differentiation by regulating type I collagen production. PMID:21173153

  5. A Tendon Cell Specific RNAi Screen Reveals Novel Candidates Essential for Muscle Tendon Interaction.

    PubMed

    Tiwari, Prabhat; Kumar, Arun; Das, Rudra Nayan; Malhotra, Vivek; VijayRaghavan, K

    2015-01-01

    Tendons are fibrous connective tissue which connect muscles to the skeletal elements thus acting as passive transmitters of force during locomotion and provide appropriate body posture. Tendon-derived cues, albeit poorly understood, are necessary for proper muscle guidance and attachment during development. In the present study, we used dorsal longitudinal muscles of Drosophila and their tendon attachment sites to unravel the molecular nature of interactions between muscles and tendons. We performed a genetic screen using RNAi-mediated knockdown in tendon cells to find out molecular players involved in the formation and maintenance of myotendinous junction and found 21 candidates out of 2507 RNAi lines screened. Of these, 19 were novel molecules in context of myotendinous system. Integrin-βPS and Talin, picked as candidates in this screen, are known to play important role in the cell-cell interaction and myotendinous junction formation validating our screen. We have found candidates with enzymatic function, transcription activity, cell adhesion, protein folding and intracellular transport function. Tango1, an ER exit protein involved in collagen secretion was identified as a candidate molecule involved in the formation of myotendinous junction. Tango1 knockdown was found to affect development of muscle attachment sites and formation of myotendinous junction. Tango1 was also found to be involved in secretion of Viking (Collagen type IV) and BM-40 from hemocytes and fat cells. PMID:26488612

  6. A Tendon Cell Specific RNAi Screen Reveals Novel Candidates Essential for Muscle Tendon Interaction

    PubMed Central

    Tiwari, Prabhat; Malhotra, Vivek; VijayRaghavan, K.

    2015-01-01

    Tendons are fibrous connective tissue which connect muscles to the skeletal elements thus acting as passive transmitters of force during locomotion and provide appropriate body posture. Tendon-derived cues, albeit poorly understood, are necessary for proper muscle guidance and attachment during development. In the present study, we used dorsal longitudinal muscles of Drosophila and their tendon attachment sites to unravel the molecular nature of interactions between muscles and tendons. We performed a genetic screen using RNAi-mediated knockdown in tendon cells to find out molecular players involved in the formation and maintenance of myotendinous junction and found 21 candidates out of 2507 RNAi lines screened. Of these, 19 were novel molecules in context of myotendinous system. Integrin-βPS and Talin, picked as candidates in this screen, are known to play important role in the cell-cell interaction and myotendinous junction formation validating our screen. We have found candidates with enzymatic function, transcription activity, cell adhesion, protein folding and intracellular transport function. Tango1, an ER exit protein involved in collagen secretion was identified as a candidate molecule involved in the formation of myotendinous junction. Tango1 knockdown was found to affect development of muscle attachment sites and formation of myotendinous junction. Tango1 was also found to be involved in secretion of Viking (Collagen type IV) and BM-40 from hemocytes and fat cells. PMID:26488612

  7. Mechanical properties of stapedial tendon in human middle ear.

    PubMed

    Cheng, Tao; Gan, Rong Z

    2007-12-01

    Measurement on mechanical properties of the stapedial tendon in human middle ear has not been reported in the literature. In this paper, we used the material testing system to conduct uniaxial tensile, stress relaxation, and failure tests on stapedial tendon specimens harvested from human temporal bones. The digital image correlation method was employed to assess the boundary effect on experimental data. The stress-strain relationship of the tendon obtained from experiments was analyzed using the hyperelastic Ogden model. The results presented include (1) the constitutive equation of the tendon for stretch ratio of 1-1.4 or stress range of 0-1.45 MPa, (2) the mean ultimate stress and stretch ratio of the tendon at 4.04 MPa and 1.65, respectively, and (3) the hysteresis and normalized stress relaxation function of the tendon. The data reported in this paper contribute to ear mechanics, especially for theoretical analysis of human ear function. PMID:18067396

  8. Biceps femoris tendon injuries sustained while playing hockey

    PubMed Central

    Watura, Christopher; Harries, William

    2011-01-01

    A 42-year-old female nurse presented in March 2008 with a left proximal hamstring tendon injury sustained while playing hockey. At surgery, the proximal biceps femoris tendon and semitendonosus were found to be ruptured and were repaired. The patient made a good recovery but sustained a further hockey injury in January 2010 involving a complete tear and rupture of the biceps femoris tendon distally. This was managed conservatively and the patient was able to return to playing hockey 10 months later. Biceps femoris tendon injuries have been reported in sport but this is the first documented case of the injury occurring while playing hockey and is also the first reported case of a biceps tendon rupture proximally (hamstring tendon) followed by distal biceps femoris rupture at the knee in the same leg. PMID:22715185

  9. Tendon graft substitutes-rotator cuff patches.

    PubMed

    Coons, David A; Alan Barber, F

    2006-09-01

    Over the past few years, many biologic patches have been developed to augment repairs of large or complex tendon tears. These patches include both allograft and xenografts. Regardless of their origins, these products are primarily composed of purified type I collagen. Many factors should be considered when choosing an augmentation patch including tissue origin, graft processing, cross-linking, clinical experience, and physical properties. The purpose of this article is to familiarize the sports medicine community with several tendon augmentation grafts: GraftJacket (Wright Medical Technology, Arlington, TN), CuffPatch (Organogenesis, Canton, MA, licensed to Arthrotek, Warsaw, IN), Restore (Depuy, Warsaw, IN), Zimmer Collagen Repair (Permacol) patch (Tissue Science Laboratories Covington, GA, licensed to Zimmer, Warsaw, IN), TissueMend (TEI Biosciences, Boston, MA, licensed to Stryker Howmedica Osteonics, Kalamazoo, MI), OrthoADAPT (Pegasus Biologics, Irvine, CA), and BioBlanket (Kensey Nash, Exton, PA). PMID:17135966

  10. An efficient robotic tendon for gait assistance.

    PubMed

    Hollander, Kevin W; Ilg, Robert; Sugar, Thomas G; Herring, Donald

    2006-10-01

    A robotic tendon is a spring based, linear actuator in which the stiffness of the spring is crucial for its successful use in a lightweight, energy efficient, powered ankle orthosis. Like its human analog, the robotic tendon uses its inherent elastic nature to reduce both peak power and energy requirements for its motor. In the ideal example, peak power required of the motor for ankle gait is reduced from 250 W to just 77 W. In addition, ideal energy requirements are reduced from nearly 36 J to just 21 J. Using this approach, an initial prototype has provided 100% of the power and energy necessary for ankle gait in a compact 0.95 kg package, seven times less than an equivalent motor/gearbox system. PMID:16995768