The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination.A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT). PMID:23396264
Guerini, H; Fermand, M; Godefroy, D; Feydy, A; Chevrot, A; Morvan, G; Gault, N; Drapé, J L
The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination. A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT).
Guerini, H.; Fermand, M.; Godefroy, D.; Feydy, A.; Chevrot, A.; Morvan, G.; Gault, N.; Drape, J.L.
Effect of glenohumeral abduction angle on the mechanical interaction between the supraspinatus and infraspinatus tendons for the intact, partial-thickness torn, and repaired supraspinatus tendon conditions.
Rotator cuff tears are difficult to manage because of the structural and mechanical inhomogeneity of the supraspinatus tendon. Previously, we showed that with the arm at the side, the supraspinatus and infraspinatus tendons mechanically interact such that conditions that increase supraspinatus tendon strain, such as load or full-thickness tears, also increase infraspinatus tendon strain. This suggests that the infraspinatus tendon may shield the supraspinatus tendon from further injury while becoming at increased risk of injury itself. In this study, the effect of glenohumeral abduction angle on the interaction between the two tendons was evaluated for supraspinatus tendon partial-thickness tears and two repair techniques. Principal strains were quantified in both tendons for 0 degrees , 30 degrees , and 60 degrees of glenohumeral abduction. Results showed that interaction between the two tendons is interrupted by an increase in abduction angle for all supraspinatus tendon conditions evaluated. Infraspinatus tendon strain was lower at 30 degrees and 60 degrees than at 0 degrees abduction angle. In conclusion, interaction between the supraspinatus and infraspinatus tendons is interrupted with increase in abduction angle. Additionally, 30 degrees abduction should be further evaluated for management of rotator cuff tears and repairs as it is the angle at which both supraspinatus and infraspinatus tendon strain is decreased. PMID:20058264
Andarawis-Puri, Nelly; Kuntz, Andrew F; Ramsey, Matthew L; Soslowsky, Louis J
Effect of Glenohumeral Abduction Angle on the Mechanical Interaction between the Supraspinatus and Infraspinatus Tendons for the Intact, Partial-thickness Torn and Repaired Supraspinatus Tendon Conditions
Rotator cuff tears are difficult to manage because of the structural and mechanical inhomogeneity of the supraspinatus tendon. Previously, we showed that with the arm at the side, the supraspinatus and infraspinatus tendons mechanically interact such that conditions that increase supraspinatus tendon strain, such as load or full-thickness tears, also increase infraspinatus tendon strain. This suggests that the infraspinatus tendon may shield the supraspinatus tendon from further injury while becoming at increased risk of injury itself. In this study, the effect of glenohumeral abduction angle on the interaction between the two tendons was evaluated for supraspinatus tendon partial-thickness tears and two repair techniques. Principal strains were quantified in both tendons for 0°, 30° and 60° of glenohumeral abduction. Results showed that interaction between the two tendons is interrupted by an increase in abduction angle for all supraspinatus tendon conditions evaluated. Infraspinatus tendon strain was lower at 30° and 60° than at 0° abduction angle. In conclusion, interaction between the supraspinatus and infraspinatus tendons is interrupted with increase in abduction angle. Additionally, 30° abduction should be further evaluated for management of rotator cuff tears and repairs as it is the angle at which both supraspinatus and infraspinatus tendon strain is decreased.
Andarawis-Puri, Nelly; Kuntz, Andrew F.; Ramsey, Matthew L.
Rotator cuff injury comprises a continual spectrum of lesions ranging from tendinopathy, which may progress to partial- or full-thickness tear. This progression may be influenced by the interplay of extrinsic and intrinsic factors. We describe the case of a 29-year-man who presented with right shoulder pain for one year. His initial magnetic resonance (MR) arthrogram showed supraspinatus tendinopathy. Subsequent MR arthrogram, obtained after a road traffic accident, showed a bursal-sided partial-thickness tear of the supraspinatus tendon. In view of his worsening clinical symptoms, surgery was performed ten months later, revealing a full-thickness rotator cuff tear near the tendon insertion, with a tight subacromial space and bony protuberance of the humeral head. The pathogenesis of rotator cuff injuries, the roles of different imaging modalities in the diagnosis of rotator cuff injuries, as well as the advantages and limitations of various radiological modalities, are discussed. PMID:24068062
Bhagwani, Sanjeev; Peh, Wilfred C G
The purpose of this study was to clarify the stress distribution in the rotator cuff tendon with 3 types of partial-thickness tears by use of 2-dimensional finite element analysis. In the finite element model of the normal human shoulder, a tendon defect was created on the articular surface, on the bursal surface, or in the midsubstance close to the insertion. A tensile force was applied to the proximal end of the tendon, and the stress distribution was calculated. In all 3 types of tears, a high stress concentration appeared around the articular surface at the insertion and at the site of the tear, which extended proximally. The maximum value of the von Mises stress increased with the presence of a partial-thickness tear. With the arm in abduction, a high stress concentration was also observed around the site of the tear. These biomechanical conditions of the supraspinatus tendon may eventually lead to a full-thickness tear at the critical zone. PMID:16414477
Sano, Hirotaka; Wakabayashi, Ikuko; Itoi, Eiji
Purpose The purpose of this study was to retrospectively evaluate sensitivity and specificity of a single magnetic resonance (MR)\\u000a arthrography series in abduction external rotation (ABER) position compared with conventional MR arthrography for detection\\u000a of supraspinatus tendon tears, with arthroscopy as gold standard, and to assess interobserver variability.\\u000a \\u000a \\u000a \\u000a Materials and methods Institutional review board approval was obtained; informed consent was waived. MR
Saskia A. Schreinemachers; Victor P. M. van der Hulst; W. Jaap Willems; Shandra Bipat; Henk-Jan van der Woude
Background and purpose Rotator cuff tears are associated with secondary rotator cuff muscle pathology, which is definitive for the prognosis of rotator cuff repair. There is little information regarding the early histological and immunohistochemical nature of these muscle changes in humans. We analyzed muscle biopsies from patients with supraspinatus tendon tears. Methods Supraspinatus muscle biopsies were obtained from 24 patients undergoing arthroscopic repair of partial- or full-thickness supraspinatus tendon tears. Tissue was formalin-fixed and processed for histology (for assessment of fatty infiltration and other degenerative changes) or immunohistochemistry (to identify satellite cells (CD56+), proliferating cells (Ki67+), and myofibers containing predominantly type 1 or 2 myosin heavy chain (MHC)). Myofiber diameters and the relative content of MHC1 and MHC2 were determined morphometrically. Results Degenerative changes were present in both patient groups (partial and full-thickness tears). Patients with full-thickness tears had a reduced density of satellite cells, fewer proliferating cells, atrophy of MHC1+ and MHC2+ myofibers, and reduced MHC1 content. Interpretation Full-thickness tears show significantly reduced muscle proliferative capacity, myofiber atrophy, and loss of MHC1 content compared to partial-thickness supraspinatus tendon tears.
Supraspinatus tendon tears are common and often propagate into larger tears that include the infraspinatus tendon, resulting in loss of function and increased pain. Previously, we showed that the supraspinatus and infraspinatus tendons mechanically interact through a range of rotation angles, potentially shielding the torn supraspinatus tendon from further injury while subjecting the infraspinatus tendon to increased risk of injury. Surgical repair of torn supraspinatus tendons is common, yet the effect of the repair on the infraspinatus tendon is unknown. Since we have established a relationship between strain in the supraspinatus and infraspinatus tendons the success of a supraspinatus tendon repair depends on its effect on the loading environment in the infraspinatus tendon. More specifically, the effect of transosseous supraspinatus tendon repair in comparison to one that utilizes suture anchors, as is commonly done with arthroscopic repairs, on this interaction through these joint positions will be evaluated. We hypothesize that at all joint positions evaluated, both repairs will restore the interaction between the two tendons. For both repairs, (1) increasing supraspinatus tendon load will increase infraspinatus tendon strain and (2) altering the rotation angle from internal to external will increase strain in the infraspinatus tendon. Strains were measured in the infraspinatus tendon insertion through a range of joint rotation angles and supraspinatus tendon loads, for the intact, transosseous, and suture anchor repaired supraspinatus tendons. Images corresponding to specific supraspinatus tendon loads were isolated for the infraspinatus tendon insertion for analysis. The effect of supraspinatus tendon repair on infraspinatus tendon strain differed with joint position. Altering the joint rotation did not change strain in the infraspinatus tendon for any supraspinatus tendon condition. Finally, increasing supraspinatus tendon load resulted in an increase in average maximum and decrease in average minimum principal strain in the infraspinatus tendon. There is a significant difference in infraspinatus tendon strain between the intact and arthroscopically (but not transosseous) repaired supraspinatus tendons that increases with greater loads. Results suggest that at low loads neither supraspinatus tendon repair technique subjects the infraspinatus tendon to potentially detrimental loads; however, at high loads, transosseous repairs may be more advantageous over arthroscopic repairs for the health of the infraspinatus tendon. Results emphasize the importance of limiting loading of the repaired supraspinatus tendon and that at low loads, both repair techniques restore the interaction to the intact supraspinatus tendon case. PMID:21303184
Andarawis-Puri, Nelly; Kuntz, Andrew F; Ramsey, Matthew L; Soslowsky, Louis J
Partial tears of the proximal hamstring tendon can successfully be managed with tendon repair in cases of failed conservative management. As in partial-thickness gluteus medius repair, a transtendinous technique can be used to repair partial-thickness undersurface tears of the hamstring origin. This report details an endoscopic transtendinous approach for the treatment of partial-thickness hamstring tendon tears.
Jackson, Timothy J.; Trenga, Anthony; Lindner, Dror; El-Bitar, Youseff; Domb, Benjamin G.
Background: Treatment of partial thickness supraspinatus tendon tears is controversial with no clearly defined treatment algorithms based on severity of tears. This study aims to evaluate the relationship between depth of partial thickness tears and strain. Methods: Bursal-sided partial thickness tears were created at 1 mm increments in depth at the anterior portion of the supraspinatus tendon to 3\\/4 tendon
Scott Yang; Hyung-Soon Park; Steven Flores; Steven D. Levin; Mohsen Makhsous; Fang Lin; Jason Koh; Gordon Nuber; Li-Qun Zhang
The vascular pattern of the supraspinatus tendon was studied in 18 human anatomic specimens. The ages of the specimens ranged from 26 to 84 years. Selective vascular injection with a silicon-rubber compound allowed visualization of the vascular bed of the rotator cuff and humeral head. The presence of a hypovascular or critical zone close to the insertion of the supraspinatus tendon into the humeral head was confirmed. However, only a uniformly sparse vascular distribution was found at the articular side, as opposed to the well-vascularized bursal side. This was also confirmed with histologic sections of the tendon. The poor vascularity of the tendon in this area could be a significant factor in the pathogenesis of degenerative rotator cuff tears. PMID:2323147
Lohr, J F; Uhthoff, H K
We analysed the morphological features of the human surgical specimens of supraspinatus tendon from patients with rotator\\u000a cuff tears. Tendon samples were harvested from 31 subjects (21 men and 10 women; mean age 51 years, range 38–64) who underwent\\u000a arthroscopic repair of a rotator cuff tear, and from five male patients who died of cardiovascular events (mean age, 69.6 years).\\u000a Histological examination
Umile Giuseppe Longo; Francesco Franceschi; Laura Ruzzini; Carla Rabitti; Sergio Morini; Nicola Maffulli; Francisco Forriol; Vincenzo Denaro
Rotator cuff tears are one of the most common tendon disorders found in the healthy population. Tendon tears not only affect the biomechanical properties of the tendon, but can also lead to debilitation of the muscles attached to the damaged tendons. The changes that occur in the muscle after tendon detachment are not well understood. A rat rotator cuff model was utilized to determine the time course of changes that occur in the supraspinatus muscle after tendon detachment. It was hypothesized that the lack of load on the supraspinatus muscle would cause a significant decrease in muscle mass and a conversion of muscle fiber properties toward those of fast fiber types. Tendons were detached at the insertion on the humerus without repair. Muscle mass, morphology and fiber properties were measured at one, two, four, eight, and 16 weeks after detachment. Tendon detachment resulted in a rapid loss of muscle mass, an increase in the proportion of fast muscle fibers, and an increase in the fibrotic content of the muscle bed, concomitant with the appearance of adhesions of the tendon to surrounding surfaces. At 16 weeks post-detachment, muscle mass and the fiber properties in the deep muscle layers returned to normal levels. However, the fiber shifts observed in the superficial layers persisted throughout the experiment. These results suggest that load returned to the muscle via adhesions to surrounding surfaces, which may be sufficient to reverse changes in muscle mass. PMID:15734235
Barton, Elisabeth R; Gimbel, Jonathan A; Williams, Gerald R; Soslowsky, Louis J
To clarify the aging process and pathogenesis of rotator cuff tears, left supraspinatus tendons from 268 cadaveric specimens (171 men and 97 women, ages 0 to 87 years) were studied. The incidence of complete thickness tear was 6.7%, and that of incomplete thickness tear was 13.8% (bursal side tears: 2.6%, intratendinous tears: 7.5% and joint side tears: 3.7%). Microscopic examinations were conducted topographically in five sites near the supraspinatus insertion. In the articular side of the tendon, there were fewer tenocytes, fewer arterioles and more chondrocyte like cells than in any other portions. The incidence of hyperplasia of intima was higher in the specimens of aged persons in all portions. At the insertion in the aged specimens the arrangement of four transitional zones became much more irregular and the numbers of tidemark was occasionally increased with granulomatous tissue. The pathogenesis of the rotator cuff tear can be ascribed to the combination of aging, enthesopathy, inherent property of the supraspinatus tendon, injury and subacromial impingement. PMID:3249097
Partial-thickness articular tears of the supraspinatus represent a not uncommon event in shoulder pathology, but their treatment\\u000a remains controversial. We believe that these lesions must be treated with surgical repair: we hereby describe our technique\\u000a of transtendon arthroscopic repair. We have treated 33 patients with an average age of 53.3 years (range 34–69). The average\\u000a follow-up was 33 months (range
R. Castricini; N. Panfoli; R. Nittoli; S. Spurio; O. Pirani
We present the case of a 13-year-old girl with painful calcific tendinitis of the supraspinatus tendon of the left shoulder. The pathologic finding was the presence of a small calcium deposit within the supraspinatus tendon. Pediatricians should be aware of this entity in shoulder pain in children. PMID:16432777
Supraspinatus tendon tears are complex yet common. We have shown that the supraspinatus and infraspinatus tendons interact, indicated by parallel changes in strain in the supraspinatus and infraspinatus with increasing size of supraspinatus tear, load applied to the supraspinatus, and changes in glenohumeral rotation but not abduction angle, suggesting disruption in the interaction between the two tendons with increase in abduction angle. While considering these factors individually is valuable, the contribution of each factor in the context of all others on strain in the supraspinatus, or on the interaction between the two tendons is unknown and has important implications in the management of rotator cuff tears. In this study, regression models using least-square estimation with backward and forward elimination were used to predict strains in the infraspinatus and supraspinatus from joint position, supraspinatus load, and supraspinatus tear size or repair. Interestingly, despite previous findings showing that supraspinatus tear size significantly affects infraspinatus strain, tear size was not a significant predictor of infraspinatus strain, emphasizing the importance of other factors evaluated such as joint position and shoulder loading in management of cuff tears and postoperative care. A better understanding of the loading environment in rotator cuff tendons necessitates multifactorial complex models.
Andarawis-Puri, Nelly; Kuntz, Andrew F.; Jawad, Abbas F.; Soslowsky, Louis J.
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.
Kim, Jihoon; John, Raheel; Walsh, Joseph T.
Objective. To measure the compressive stiffness of the supraspinatus tendon and to determine whether regional difference exists in the bursal and articular side of the tendon.Design. Indentation testing was performed on both the bursal and articular sides of the supraspinatus tendon, focused on the ‘critical area’, where rotator cuff tears often occur.Background. When the supraspinatus tendon wraps around the humeral
Seok-Beom Lee; Tomotaka Nakajima; Zong-Ping Luo; Mark E Zobitz; Yi-Wen Chang; Kai-Nan An
OBJECTIVE. Our objective was to determine the association between size and chronicity of full-thickness supraspinatus tendon tears with subscapularis tendon abnormalities on MRI. MATERIALS AND METHODS. One hundred forty-two MRI examinations with full- thickness supraspinatus tendon tears were categorized on the basis of the supraspinatus muscle (SS): normal muscle (SSnormal), suggesting a recent or small tear; reduced muscle bulk without
Diane Bergin; Laurence Parker; Adam Zoga; William Morrison
Disorders of the rotator cuff, particularly tears of the rotator cuff tendons, cause significant shoulder disability. Among numerous factors thought to be responsible for the initiation and progression of supraspinatus tears are those related to the tendon’s biomechanical properties. We hypothesized that in supraspinatus tendons subjected to tensile loading a strain gradient (difference) exists between the articular and bursal tendon
Chun-Yuh Huang; Vincent M. Wang; Robert J. Pawluk; John S. Bucchieri; William N. Levine; Louis U. Bigliani; Van C. Mow; Evan L. Flatow
A 45-year-old woman presented to the emergency department with a 2-day history of severe left shoulder pain made worse with movement. Emergency department (ED) bedside point-of-care static and dynamic ultrasound examination of the supraspinatus tendon revealed supraspinatus tendon calcification with impingement syndrome, and the patient was urgently referred to orthopedics after ED pain control was achieved. Bedside shoulder and supraspinatus tendon evaluation with static and dynamic ultrasonography can assist in the rapid diagnosis of supraspinatus tendon calcification and supraspinatus tendon impingement syndrome in the emergency department.
Rotator cuff tears are one of the most common tendon disorders found in the healthy population. Tendon tears not only affect the biomechanical properties of the tendon, but can also lead to debilitation of the muscles attached to the damaged tendons. The changes that occur in the muscle after tendon detachment are not well understood. A rat rotator cuff model
Elisabeth R. Barton; Jonathan A. Gimbel; Gerald R. Williams; Louis J. Soslowsky
Background: There are few biomechanical studies regarding partial-thickness rotator cuff tears and subsequent repair.Hypothesis: Partial-thickness intra-articular supraspinatus tendon tears increase articular-sided tendon strain as they increase in size. Repair of these tears will return strain to the intact state.Study Design: Controlled laboratory study.Methods: Twenty fresh-frozen human cadaveric shoulders were prepared by dissecting to the supraspinatus tendon and leaving the native
Augustus D. Mazzocca; Lina M. Rincon; Robert W. OConnor; Elifho Obopilwe; Matthew Andersen; Lauren Geaney; Robert A. Arciero
Background: Rotator cuff tears are common and not well-understood shoulder problems. Structural and mechanical inhomogeneity of the supraspinatus tendon complicates accurate prediction of risk of tear propagation and may affect appropriate clinical treatment.Hypothesis: We propose that interactions between the supraspinatus and infraspinatus tendons are critical to load bearing at the glenohumeral joint and warrant investigation.Study Design: Controlled laboratory study.Methods: Principal
Nelly Andarawis-Puri; Eric T. Ricchetti; Louis J. Soslowsky
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. Clin. Anat. 27:702-706, 2014. © 2013 Wiley Periodicals, Inc. PMID:24214830
Matsuhashi, Tomoya; Hooke, Alexander W; Zhao, Kristin D; Goto, Akira; Sperling, John W; Steinmann, Scott P; An, Kai-Nan
Background We analyzed the mechanical environment of the supraspinatus tendon using a three-dimensional finite element model with the\\u000a software programs MENTAT and MARC.\\u000a \\u000a \\u000a \\u000a Methods The supraspinatus tendon that attaches to the superior facet was extracted and modeled. The geometric shape of the humeral\\u000a head was determined from computed tomography images, and the shape of the supraspinatus tendon was determined from magnetic\\u000a resonance
Nobutoshi Seki; Eiji Itoi; Yotsugi Shibuya; Ikuko Wakabayashi; Hirotaka Sano; Ryuji Sashi; Hiroshi Minagawa; Nobuyuki Yamamoto; Hidekazu Abe; Kazuma Kikuchi; Kyoji Okada; Yoichi Shimada
Background: To date, no studies document the effect of anabolic steroids on rotator cuff tendons.Study Design: Controlled laboratory study.Hypothesis: Anabolic steroids enhance remodeling and improve the biomechanical properties of bioartificially engineered human supraspinatus tendons.Methods: Bioartificial tendons were treated with either nandrolone decanoate (nonload, steroid, n = 18), loading (load, nonsteroid, n = 18), or both (load, steroid, n = 18).
Ioannis K. Triantafillopoulos; Albert J. Banes; Karl F. Bowman; Melissa Maloney; William E. Garrett; Spero G. Karas
We performed 2-dimensional finite element model analysis to estimate the mechanical environment of the supraspinatus tendon. The geometric shape of the finite element model was determined by magnetic resonance imaging of a normal human shoulder obtained at 0°, 30°, and 60° of abduction, whereas the histologic location of noncalcified and calcified fibrocartilage was determined from a cadaveric specimen. The supraspinatus
Ikuko Wakabayashi; Eiji Itoi; Hirotaka Sano; Yotsugi Shibuya; Ryuji Sashi; Hiroshi Minagawa; Moto Kobayashi
We performed 2-dimensional finite element model analysis to estimate the mechanical environment of the supraspinatus tendon. The geometric shape of the finite element model was determined by magnetic resonance imaging of a normal human shoulder obtained at 0 degrees, 30 degrees, and 60 degrees of abduction, whereas the histologic location of noncalcified and calcified fibrocartilage was determined from a cadaveric specimen. The supraspinatus tendon was pulled proximally with the force of 10 N at 0 degrees, 53 N at 30 degrees, and 115 N at 60 degrees of abduction. The area of high principal stress maximum was observed on the articular side of the supraspinatus tendon, which shifted toward the insertion as the arm was abducted. High stress concentration on the articular side of the supraspinatus tendon near its insertion during arm elevation may explain the frequent occurrence of rotator cuff tears at this site. PMID:14671529
Wakabayashi, Ikuko; Itoi, Eiji; Sano, Hirotaka; Shibuya, Yotsugi; Sashi, Ryuji; Minagawa, Hiroshi; Kobayashi, Moto
Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repair of rotator cuff tendon tears depends on the time from onset of injury to the time of surgical repair. However, the effect of time from injury to repair remains poorly understood. A rat model was used to investigate the supraspinatus tendon organizational and
Jonathan A. Gimbel; Jonathan P. Van Kleunen; Samir Mehta; Stephanie M. Perry; Gerald R. Williams; Louis J. Soslowsky
The aim of this study was to compare the diagnostic reliability of US with MR arthrography in diagnosing supraspinatus tendon tears. Surgical findings were used as the gold standard in detecting tears. A total of 44 patients were assessed with transverse and longitudinal US scans with respect to the long axis of the rotator cuff tendons and then ex- amined
Francesco S. Ferrari; Simone Governi; Francesca Burresi; Francesco Vigni; Paolo Stefani
Disorders of the rotator cuff, particularly tears of the rotator cuff tendons, cause significant shoulder disability. Among numerous factors thought to be responsible for the initiation and progression of supraspinatus tears are those related to the tendon's biomechanical properties. We hypothesized that in supraspinatus tendons subjected to tensile loading a strain gradient (difference) exists between the articular and bursal tendon surfaces, that regional strain differences exist on each of these two tendon surfaces, and that tendon surface strains vary with glenohumeral abduction. To test these hypotheses, the intrinsic inhomogeneous deformational characteristics of the articular and bursal surfaces of eight intact human cadaveric supraspinatus tendons were studied at three glenohumeral abduction angles using a novel multiple strain measuring system which simultaneously recorded surface marker displacements on two opposing soft tissue surfaces. Under applied tensile loads, the articular surface exhibited greater strain at 22 degrees (7.4+/-2.6% vs. 1.3+/-0.7%, p=0.0002) and 63 degrees (6.4+/-1.6% vs. 2.7+/-1.2%, p=0.0001) whereas the bursal surface exhibited greater strain at 90 degrees (7.6+/-2.8% vs. 4.9+/-0.4%, p=0.013). At all abduction angles, insertion strains were higher than those of the mid-tendon and tendon-muscle junction regions. The existence of inhomogeneous surface strains in the intact supraspinatus tendon demonstrates that intratendinous shear occurs within the tendon. The higher strain on the articular side of the tendon, especially at the insertion region, suggests a propensity for tears to initiate in the articular tendinous zone. PMID:16023009
Huang, Chun-Yuh; Wang, Vincent M; Pawluk, Robert J; Bucchieri, John S; Levine, William N; Bigliani, Louis U; Mow, Van C; Flatow, Evan L
A distinct type of partial-thickness rotator cuff tear has been observed in overhead athletes, characterized by partial failure of the undersurface of the posterior supraspinatus and anterior infraspinatus tendons with intratendinous delamination. We present a technique of percutaneous intratendinous repair using nonabsorbable mattress sutures designed for the management of articular-side delaminated partial-thickness tears. After tear evaluation and preparation, the torn
Stephen F. Brockmeier; Christopher C. Dodson; Seth C. Gamradt; Struan H. Coleman; David W. Altchek
Background: Good functional results have been reported for arthroscopic repair of rotator cuff tears, but the rate of tendon-to-bone healing is still unknown. Our hypothesis was that arthroscopic repair of full-thickness supraspinatus tears achieves a rate of complete tendon healing equivalent to those reported in the literature with open or mini-open techniques. Methods: Sixty-five consecutive shoulders with a chronic full-thickness
PASCAL BOILEAU; NICOLAS BRASSART; DUNCAN J. WATKINSON; MICHEL CARLES; ARMODIOS M. HATZIDAKIS; SUMANT G. KRISHNAN
Summary \\u000a The traumatic tear of the rotator cuff has been discussed very intensively for a long time despite the fact that there do\\u000a not exist representative objective data about the native tensile strength of these tendons. The aim of this study was to evaluate\\u000a the age related native strength of the supraspinatus tendon. 25 fresh frozen cadaver specimen (age: 23–94,
M. Rickert; H. Georgousis; U. Witzel
Introduction Partial articular surface of the rotator cuff tendon tears has been recognized as a source of treatable shoulder pain and\\u000a a precursory pathology for full-thickness tendon tears. Arthroscopic rotator cuff repair is a possible surgical method of\\u000a treatment. Recent data have shown that the treating partial-thickness rotator cuff repairs with transtendon technique shows\\u000a good clinical outcome. The use of this
Jong-Hun Ji; Mohamed Shafi; Jae-Jung Jeong; Yeon Soo Lee; Edward G. McFarland; Tae-Kwen Kim; Jun-Young Chung
Objectives To examine the dose–response relationship between cumulative duration of work with highly elevated arms (work above shoulder\\u000a level) as well as of manual material handling and ruptures of the supraspinatus tendon in a population-based case–control\\u000a study.\\u000a \\u000a \\u000a \\u000a \\u000a Methods In 14 radiologic practices, we recruited 483 male patients aged 25–65 with radiographically confirmed partial (n = 385) or total (n = 98) supraspinatus tears associated with shoulder
Andreas Seidler; Ulrich Bolm-Audorff; Gabriela Petereit-Haack; Elke Ball; Magdalena Klupp; Noëlle Krauss; Gine Elsner
Background: The precise results of arthroscopic transtendon repair of partial-thickness articular-side tears of the rotator cuff remain to be reported.Hypothesis: Arthroscopic transtendon repair is useful in patients with Ellman grade 3 (>6 mm) partial-thickness articular-side tears of the supraspinatus tendon.Study Design: Descriptive laboratory study and case series; Level of evidence, 4.Methods: In 43 cadaveric shoulders (mean age, 80 years; range,
Junji Ide; Satoshi Maeda; Katsumasa Takagi
Background Rotator cuff repair re-tear rates range from 25-90% necessitating methods to improve repair strength. While numerous laboratory studies have compared single to double row fixation properties, little is known regarding regional (i.e., medial versus lateral) suture retention properties in both intact and torn tendons. Hypothesis A torn supraspinatus tendon will have reduced suture retention properties on the lateral aspect of the tendon compared to the more medial musculotendinous junction. Study Design Controlled Laboratory Study Methods Human supraspinatus tendons (torn and intact) were randomly assigned for suture retention mechanical testing, ultrastructural collagen fibril analysis, or histology following suture pullout testing. For biomechanical evaluation, sutures were placed either at the musculotendinous junction (medial) or 10 mm from the free margin (lateral), and tendons were elongated to failure. Collagen fibril assessments were performed using transmission electron microscopy (TEM). Results Intact tendons showed no regional differences with respect to suture retention properties. In contrast, among torn tendons the medial region exhibited significantly higher stiffness and work values relative to the lateral region. For the lateral region, work to 10 mm displacement (1592±261 N-mm) and maximum load (265±44 N) for intact tendons were significantly higher (p<0.05) than those of torn tendons (1086±388 N-mm and 177±71 N, respectively). For medial suture placement, maximum load, stiffness and work of intact and torn tendons were similar (p>0.05). Regression analyses for the intact and torn groups revealed generally low correlations between donor age and the three biomechanical indices. For both intact and torn tendons, the mean fibril diameter and area density were greater in the medial region relative to the lateral (p?0.05). In the lateral tendon, but not the medial region, torn specimens showed a significantly lower fibril area fraction (48.3±3.8%) than intact specimens (56.7±3.6%, p<0.05). Conclusions Superior pullout resistance of medial placed sutures may provide a strain shielding effect for the lateral row following double row repair. Larger diameter collagen fibrils as well as greater fibril area fraction in the medial supraspinatus tendon may provide greater resistance to suture migration. Clinical Relevance While clinical factors such as musculotendinous integrity warrant strong consideration for surgical decision making, the present ultrastructural and biomechanical results appear to provide a scientific rationale for double-row rotator cuff repair where sutures are placed more medial at the muscle tendon junction.
Wang, Vincent M.; Wang, FanChia; McNickle, Allison G.; Friel, Nicole A.; Yanke, Adam B.; Chubinskaya, Susan; Romeo, Anthony A.; Verma, Nikhil N.; Cole, Brian J.
During the repair of some rotator-cuff tears, the torn tendon cannot be freed up adequately to permit reattachment at its original anatomical site of insertion. An option is to advance the site of insertion medially and reattach the tendon to a trough in the sulcus or to the humeral head. The biomechanical effects of such medial advancement on the moment arm of the supraspinatus muscle during glenohumeral elevation were studied in ten fresh-frozen shoulders from cadavera. Medial advancement of the site of insertion of the supraspinatus tendon was simulated by the placement of suture anchors in the sulcus of the proximal part of the humerus at points three, ten, and seventeen millimeters medial to the junction of the supraspinatus tendon and the bone. These distances were chosen not because they represent clinical options but because the large range allowed biomechanical study of medial advancement. Nylon lines were attached to the suture anchors and were passed back through an eyehook at the midpoint of the supraspinatus muscle. The excursion of each line was measured as the humerus was elevated, and the moment arm was estimated from the joint angle and excursion data with use of the principle of virtual work. Three and ten millimeters of medial advancement of the tendon (attachment in the sulcus) had a minimum (non-significant) effect on the moment arm during elevation compared with the value determined for the intact condition. However, seventeen millimeters of medial advancement was found to reduce the moment arm significantly (p < 0.05). PMID:9655103
Liu, J; Hughes, R E; O'Driscoll, S W; An, K N
Exploration of the rotator interval during repair of 116 apparently "isolated" supraspinatus tendon lesions have revealed "hidden lesions" of the coracohumeral ligament, the superior glenohumeral ligament, and the superior portion of the subscapularis tendon in 19 cases. Epidemiologic characteristics were comparable with other series with the exception of involvement of the dominant shoulder in 95%. Arthroscopic computed tomography documented the lesion in 85% of the cases. At surgery the superficial layer of the coracohumeral ligament was always intact. After splitting of the rotator interval the lesion was visible and consisted of a local disinsertion of the common insertion of the superior glenohumeral ligament and the coracohumeral ligament and the deep superior fibers of the subscapularis tendon. It measured 1 to 2 cm in the superior-inferior direction. The biceps tendon was ruptured in 2 cases, subluxated in 14, and in its normal position in 5. The treatment consisted of intraosseous reinsertion of the supraspinatus tendon, recentering of the biceps, and reinsertion of the torn structures to reconstruct a functional pulley system. The patients have been reviewed with a mean follow-up of 20 months (range 12 to 36 months). A secondary rupture of the long head of the biceps has been observed in 25% of the cases after recentering of the tendon. PMID:22958839
Walch, G; Nove-Josserand, L; Levigne, C; Renaud, E
Background More than one-quarter of Americans are hypercholesterolemic and/or being treated with cholesterol-lowering medications. Given the systemic nature of hypercholesterolemia and remaining questions regarding its effect on tendons at a local level, we sought to assess the utility of small versus large animal model systems for translational studies by exploring the effect of hypercholesterolemia on supraspinatus tendon elastic mechanical properties in mice, rats, and monkeys. We hypothesized that stiffness and elastic modulus would be increased in tendons across species due to hypercholesterolemia. Materials and Methods Supraspinatus tendons from normal (CTL) and high-cholesterol (HC) mice, rats, and monkeys were used in this study. Following dissection, tendons were geometrically measured and tensile tested with tissue strain measured optically. Results Overall, HC animals had significantly altered plasma lipid profiles. Biomechanical testing showed a significant increase in stiffness compared to CTL in HC mice and rats, as well as a non-significant trend for HC monkeys. Elastic modulus was also significantly increased in HC mice and monkeys, with HC rats showing a trend. Conclusions The consistency of the present findings across species and between small and large animals, combined with the fact that the aged mice were exposed to lifelong hypercholesterolemia (compared with rats and non-human primates which were fed high-cholesterol diets) suggests that these increased properties may be inherent to the effect of hypercholesterolemia on supraspinatus tendon rather than due to an effect of cumulative exposure time to the effects of high cholesterol. Further investigation is needed to confirm this concept.
Beason, David P.; Hsu, Jason E.; Marshall, Stephanie M.; McDaniel, Allison L.; Temel, Ryan E.; Abboud, Joseph A.; Soslowsky, Louis J.
The collagen fibres in the area of attachment of the supraspinatus tendon to bone were studied immunohistochemically in 12 mature female New Zealand white rabbits. The labelling of type I collagen was uniformly prominent in the bone as well as in the fascicles of the tendon proper but inconspicuously scattered in the unmineralised and mineralised zones of the fibrocartilage. Type II collagen, not detected in the tendon proper, was widespread in both zones of the fibrocartilage. Type III collagen, on the other hand, appeared to be confined mainly to the zone of unmineralised fibrocartilage, in addition to its presence in the endotenon of the tendon proper. The region of the tidemark failed to show immunostaining for any of the collagen fibre types. In conclusion, this study demonstrates that, although all the principal fibrous collagen types are constituents of the supraspinatus tendon at its attachment site, the distribution pattern of immunolabelling varies from zone to zone. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5
Kumagai, J; Sarkar, K; Uhthoff, H K; Okawara, Y; Ooshima, A
A bursal- or joint-side incomplete thickness tearing of the rotator cuff is clinically important, because it is known that this tearing has the potential to develop into a complete tendon disruption. Normal cadaveric supraspinatus tendons were analyzed histologically and biomechanically to clarify the differences in pathomechanical causation of bursal- and joint-side incomplete tears. Histologically, the bursal-side layer was composed of tendon bundles with a decreasing muscular component toward the insertion. The joint-side layer was a complex of tendon, ligament, and joint capsule without transitional areas. Biomechanically, the bursal-side layer had greater deformation and tensile strength. When each layer was divided into three portions of equal length, the middle segment of the bursal-side layer elongated the most, whereas the entire joint-side layer increased evenly in length. We conclude that the joint-side layer is more vulnerable to a tensile load than the bursal-side layer. PMID:22959646
Nakajima, T; Rokuuma, N; Hamada, K; Tomatsu, T; Fukuda, H
Rotator cuff tears occur frequently and can cause significant pain and reduced shoulder function. A high percentage of patients are satisfied after surgical repair of rotator cuff tears, but a smaller percentage of patients with chronic tears continue to have pain and poor shoulder function. This may be partly attributable to an increase in the repair tension, the force required at repair to reappose the tendon to its original insertion site on the humerus. Increases in repair tension have been shown to occur for long-standing ruptures of the supraspinatus tendon, but the precise tension at various times after injury are unknown. Therefore, the objective of the current study was to determine the repair tension at various times after a rotator cuff tear. This was achieved by creating a full-thickness supraspinatus tendon tear in a rat model and measuring the mechanical characteristics of the musculotendinous unit at 0, 2, 4, 9, and 16 weeks after injury. The repair tension rapidly increased initially after injury followed by a progressive, but less dramatic, increase with additional time. These findings suggest that rotator cuff tears should be repaired early in the clinical setting. Future studies will investigate the effect of repair tension on tendon to bone healing after repair. PMID:15346083
Gimbel, Jonathan A; Mehta, Samir; Van Kleunen, Jonathan P; Williams, Gerald R; Soslowsky, Louis J
Rotator cuff tears of the shoulder are a common cause of pain and disability. The successful repair of rotator cuff tendon tears depends on the time from onset of injury to the time of surgical repair. However, the effect of time from injury to repair remains poorly understood. A rat model was used to investigate the supraspinatus tendon organizational and mechanical property changes that occur with time post-injury to understand the natural injury response in the absence of repair. It was hypothesized that increased time post-injury would result in increased detrimental changes to tendon organizational and mechanical properties. Tendons were detached at the insertion on the humerus without repair and the quantitative organizational and mechanical properties were analyzed at 1, 2, 4, 8, and 16 weeks post-detachment. Tendon detachment resulted in a dramatic decrease in mechanical properties initially followed by a progressive increase with time. The quantitative collagen fiber orientation results provided corroborating support to the mechanical property data. Based on similarities in histology and mechanical properties to rotator cuff tears in humans, the animal model presented here is promising for future investigations of the tendon's natural injury response in the absence of repair. PMID:15047003
Gimbel, Jonathan A; Van Kleunen, Jonathan P; Mehta, Samir; Perry, Stephanie M; Williams, Gerald R; Soslowsky, Louis J
Purpose The aim of the study was to evaluate whether arthroscopic (ASC) repair of rotator cuff ruptures causes less postoperative\\u000a pain and better range of motion (ROM) in the early postoperative period than a mini-open (MO) technique.\\u000a \\u000a \\u000a \\u000a \\u000a Methods Inclusion criteria were a rupture of the supraspinatus tendon with retraction with a maximum to the apex of the humeral head\\u000a and minor fatty
Philip Kasten; Christoph Keil; Thomas Grieser; Patric Raiss; Nikolaus Streich; Markus Loew
Background Rotator cuff tendon tear is a leading cause for atrophy, fibrosis and fatty infiltration of the rotator cuff muscles. The pathophysiology of fatty muscle infiltration is not well understood. An animal model suited to study cellular and molecular mechanisms would therefore be desirable. While a rat model has been established for chronic rotator cuff tendon pathology, sufficient and easily identifiable fatty infiltration of the muscle has not yet been shown in rats. As younger animals regenerate better, we hypothesized that the absence of a sufficient amount of fatty infiltration in previous experiments was due to the selection of young animals and that older animals would exhibit higher amounts of fatty infiltration after tendon tear. Findings The supraspinatus tendon was released using tenotomy in 3 young (6 weeks old) and in 3 aged (24 months old) Sprague Dawley rats (group I and II). Another 3 aged (24 months old) rats underwent sham surgery and served as a control group (group III). In group I and II retraction of the musculotendinous unit was allowed for 6 weeks. All animals were sacrificed 6 weeks after surgery and the supraspinatus muscles were harvested. Each sample was examined for fatty infiltration of the muscle by histological methods and micro-CT. In histology, fat cells were counted with a 10-fold magnification in 6 fields of view twice. An adjusted measurement setup was developed for the use of micro-CT to quantify the absorption coefficient of the muscle as a reciprocal indicator for fatty infiltration, based on the established procedure for quantification of fatty infiltration on CT in humans. Tenotomy resulted in an insignificant increase of fat cells in histological sections in both, aged and young rats. Micro-CT was able to quantify small differences in the absorption coefficients of muscle samples; the absorption coefficient was 8.1% ± 11.3% lower in retracted muscles (group I and II) compared with the control (group III), indicating a tendency towards a higher amount of intra- and/or extracellular fat. Absorption was 4.28% ± 3.2% higher in aged compared with young muscles; however, this difference could not be confirmed by histology. Conclusions Substantial fatty muscle infiltration following chronic retraction after supraspinatus tenotomy could be documented histologically neither in young nor aged rats. Although micro-CT was able to reveal minor differences in absorption between the studied groups, the differences were too small to make the rat supraspinatus model interesting to study fatty infiltration of the chronically retracted muscle.
It was hypothesized that there would be an alteration in strain when macroscopically normal supraspinatus tendons were subjected to three patterns of surgically created tear. The propagation of joint-side partial-thickness tears was also examined. Cadaveric shoulders were tested on a purpose-built rig with static loading from 20 to 200 N and during glenohumeral abduction from 0° to 120° with a
Peter Reilly; Andrew A. Amis; Andrew L. Wallace; Roger J. H. Emery
The purpose was to evaluate histological changes of the supraspinatus tendon (SSP) after refixation under continuous growth factor application over 20 days in comparison to the native healing process. In a chronic rat tendon tear model (15 rats/group), a transosseous SSP refixation was performed and growth factors (control, G-CSF, b-FGF, combination) were continuously released into the subacromial space by an osmotic pump. Tendon healing was evaluated histologically by a modified MOVIN-Score, and Collagen I/III content was determined by immunohistology at 6 weeks. A modified MOVIN sum score showed significant lower counts for G-CSF and b-FGF in comparison to the control group (p = 0.050/p = 0.027) and the combined group (p = 0.050/p = 0.043). Collagen III was significantly reduced in the combined group compared to the control group (p = 0.028). Collagen I showed no significant differences. The Collagen I/III ratio was nearly doubled for b-FGF and the combined group compared to the control. At the study endpoint, 33% of pump dislocations were detected. The continuous application of both isolated growth factors (G-CSF/b-FGF) achieved improved tendon-remodeling. However, the continuous application via an osmotic pump showed a relative high dislocation rate when applied in the rat model. PMID:22912341
Buchmann, Stefan; Sandmann, Gunther H; Walz, Lars; Hoppe, Henriette; Beitzel, Knut; Wexel, Gabriele; Tian, Weiwei; Winter, Gerhard; Imhoff, Andreas B
Aim: This study aims to measure strains on the different rotator cuff tendons simultaneously and demonstrate the effect of\\u000a supraspinatus tear on other cuff tendons with an intact glenohumeral joint.\\u000a \\u000a Methodology: Four fresh-frozen shoulders were tested on a purpose-built rig in preliminary tests. With 10 kg loaded at the\\u000a rotator cuff muscles, displacement variable reluctance transducers (DVRTs) were used to
J. M. Sheng; S. M. Chou; S. H. Tan; D. T. T. Lie; K. S. A. Yew
Overuse activity has been implicated as an etiologic factor in injury to the rotator cuff and to the supraspinatus tendon in particular. Due in part to the lack of an appropriate animal model, experimental studies have not addressed this issue. With the use of a rat model, we measured the effects of an overuse running regimen on 36 Sprague-Dowley rats
L. J. Soslowsky; S. Thomopoulos; S. Tun; C. L. Flanagan; C. C. Keefer; J. Mostow; J. E. Carpenter
While tendons typically undergo primarily tensile loading, the human supraspinatus tendon (SST) experiences substantial amounts of tension, compression, and shear in vivo. As a result, the functional roles of the extracellular matrix components, in particular the proteoglycans (PGs), are likely complex and important. The goal of this study was to determine the PG content in specific regions of the SST that exhibit differing mechanical function. The concentration of aggrecan, biglycan, and decorin were determined in six regions of the human SST using immunochemical techniques. We hypothesized that: aggrecan concentrations would be highest in areas where the tendon likely experiences compression; biglycan levels would be highest in regions likely subjected to injury and/or active remodeling such as the anterior regions; decorin concentrations would be highest in regions of greatest tensile stiffness. Our results generally supported these hypotheses and demonstrated that aggrecan and biglycan share regional variability, with increased concentration in the anterior and posterior regions and smaller concentration in the medial regions. Decorin, however, was in high concentration throughout all regions. The data presented in this study represent the first regional measurements of PG in the SST. Together with our previous regional measurements of mechanical properties, these data can be used to evaluate SST structure-function relationships. With knowledge of the differences in specific PG content, their spatial variations in the SST, and their relationships to tendon mechanics, we can begin to associate defects in PG content with specific pathology, which may provide guidance for new therapeutic interventions.
Matuszewski, Paul E; Chen, Yi-Ling; Szczesny, Spencer E; Lake, Spencer; Elliott, Dawn M; Soslowsky, Louis J; Dodge, George R
The purpose of this investigation was to determine the relationship between the degree of degeneration at the supraspinatus insertion, the tensile strength, and the site of failure of this tendon. Thirty-three fresh cadaveric shoulders (average age: 62 years; range: 39-83 years) were examined. A tensile load to failure was applied at a constant crosshead speed of 25.4 mm/min to a 10 mm wide strip of the supraspinatus tendon that remained attached to the bone. Preexisting degenerative changes at the insertion were assessed and scored histologically and compared with the ultimate tensile stress. Twenty tendons failed at the insertion (the insertion group), and 11 failed in the midsubstance (the midsubstance group). The histologic score of degeneration for the insertion group was significantly higher than that for the midsubstance group (p = 0.0026). There was a negative correlation between the ultimate tensile stress at the insertion and the degeneration score for the insertion group (r = -0.60; p = 0.013). Histologic observations revealed that disruptions of tendon fibers were located mostly in the articular half of the tendon and that they enlarged during mechanical testing in 90% of the specimens of the insertion group. It seems that degenerative changes at the supraspinatus insertion reduce the tensile strength of the tendon and constitute a primary pathogenetic factor of rotator cuff tear. PMID:9420602
Sano, H; Ishii, H; Yeadon, A; Backman, D S; Brunet, J A; Uhthoff, H K
Mineralization of the supraspinatus tendon was diagnosed in 24 large-breed dogs as a probable cause for a chronic unilateral forelimb lameness. Owners of 12 dogs responded to a questionnaire survey evaluating the treatment that their dog had received which consisted of either surgical removal of the mineralization after failure of conservative treatment (operated group; n=9) or rest and nonsteroidal anti-inflammatory drugs (NSAIDs) (nonoperated group; n=3). In eight out of the 12 dogs, the mineralization was also present in the asymptomatic forelimb. Based on owner evaluation, the degree of lameness had decreased distinctly in both groups. Six dogs (four operated and two nonoperated) were reevaluated at Michigan State University Veterinary Teaching Hospital (MSU-VTH) and were without lameness except for one dog in the operated group. The mineralizations had reformed in all dogs in the operated group after a mean follow-up time of 5.1 years. PMID:10825100
Laitinen, O M; Flo, G L
Rotator cuff tears are a common shoulder pathology and are hypothesized to relate to excessive tissue deformation. Few data exist, however, describing deformation of the rotator cuff as an intact, functional unit. Our purpose was to determine regional variations of intratendinous rotator cuff strain over a range of clinically relevant joint positions. A novel, MRI-based technique was utilized to quantify intratendinous strains in cadaveric shoulder specimens at 15 degrees, 30 degrees, 45 degrees, and 60 degrees of glenohumeral abduction in the scapular plane. The strain data were grouped into superior, middle, and inferior locations across the region where most rotator cuff tears occur clinically. A repeated measures ANOVA assessed the effects of joint position and tendon region on intratendinous strain. Few differences in intratendinous strain existed across tendon regions, but joint position had a pronounced effect. Specifically, intratendinous strain increased with increasing joint angle, and the 60 degrees strain was significantly greater than the 15 degrees strain across all tendon regions. These data suggest that joint position plays a larger role in rotator cuff mechanics than previously believed. Future studies will utilize this technique for quantifying intratendinous strain to assess the effects of partial-thickness rotator cuff tears. PMID:12168680
Bey, Michael J; Song, Hee Kwon; Wehrli, Felix W; Soslowsky, Louis J
Ruptures of the subscapularis tendon, isolated or combined, are rare, and the treatment modalities are controversial. Of 1345 patients who underwent rotator cuff repair in a 7-year period, 73 had either an isolated rupture of the subscapularis or a subscapularis rupture combined with rupture of the supraspinatus. All reconstructions were performed through a deltopectoral approach. Reinsertion of the subscapularis was combined with reconstruction of the supraspinatus in 32 patients. Of the patients, 63 (86%) were re-examined at a mean follow-up of 35 months. The modified Constant score improved from 62% preoperatively to 91% at follow-up. Isolated or combined reconstructions did not result in significant differences with respect to the Constant score. Of the patients, 62 (98%) were satisfied with the operation. Rerupture was found by ultrasound in 8 subscapularis tendons (13%) and 4 supraspinatus tendons (13%). The rerupture rate showed a significant correlation with the Goutallier stage of fatty degeneration and the interval between injury and operation. PMID:17055750
Flury, Matthias P; John, M; Goldhahn, J; Schwyzer, H-K; Simmen, B R
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.
Reuther, Katherine E.; Thomas, Stephen J.; Sarver, Joseph J.; Tucker, Jennica J.; Lee, Chang-Soo; Gray, Chancellor F.; Glaser, David L.; Soslowsky, Louis J.
Rotator cuff tears frequently occur and can lead to pain and decreased shoulder function. Repair of the torn tendon back to bone is often successful in relieving pain, but failure of the repair commonly occurs. Post-operative activity level is an important treatment component that has received minimal attention for the shoulder, but may have the potential to enhance tendon to bone healing. The objective of this study was to investigate the effect of short and long durations of various activity levels on the healing supraspinatus tendon to bone insertion site. Rotator cuff tears were surgically created in Sprague-Dawley rats by detaching the supraspinatus tendon from its insertion on the humerus and these tears were immediately repaired back to the insertion site. The post-operative activity level was controlled through shoulder immobilization (IM), cage activity (CA), or moderate exercise (EX) for durations of 4 or 16 weeks. The healing tissue was evaluated utilizing biomechanical testing and a quantitative polarized light microscopy method. We found that activity level had no effect on the elastic properties (stiffness, modulus) of the insertion site at four weeks post injury and repair, and a decreased activity level had a positive effect on these properties at 16 weeks (IM>CA=EX). Furthermore, a decreased activity level had the greatest positive effect on these properties over time (IM>CA=EX). The angular deviation of the collagen, a measure of disorganization, was decreased with a decrease in activity level at 4 weeks (IM
Gimbel, J A; Van Kleunen, J P; Williams, G R; Thomopoulos, S; Soslowsky, L J
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 must be examined. PMID:22482687
Miller, Kristin S; Edelstein, Lena; Connizzo, Brianne K; Soslowsky, Louis J
We hypothesized that botulinumneurotoxin A (BoNtA) positively influences tissue characteristics at the re-insertion site when used as an adjuvant prior to rotator cuff repair. One hundred and sixty Sprague-Dawley rats were randomly assigned to either a BoNtA or saline-injected control group. BoNtA or saline solution was injected into the supraspinatus muscle one week prior to repair of an artificially created supraspinatus tendon defect. Post-operatively, one subgroup was immobilized using a cast on the operated shoulder while the other had immediate mobilization. Histologically, the fibrocartilage transition zone was more prominent and better organized in the BoNtA groups when compared to the saline control group. In the immediately mobilized BoNtA groups significantly more collagen 2 at the insertion was detected than in the control groups (p<0.05). Fiber orientation of all BoNtA groups was better organized and more perpendicular to the epiphysis compared with control groups. Tendon stiffness differed significantly (p<0.05) between casted BoNtA and casted saline groups. Tendon viscoelasticity was significantly higher (p<0.05) in the immobilized saline groups no matter if repaired with increased or normal repair load. The results of this study suggest that reduction of load at the healing tendon-to-bone interface leads to improved repair tissue properties. PMID:24409812
Ficklscherer, A; Scharf, M; Hartl, T K; Schröder, C; Milz, S; Roßbach, B P; Gülecyüz, M F; Pietschmann, M F; Müller, P E
We report the use of the double-pulley technique for arthroscopic fixation of the bony PASTA (partial articular surface tendon avulsion) lesion. Arthroscopic examination documented a 15-mm-long and 8-mm-wide comminuted bony avulsion with 2 main fragments. Two double-loaded suture anchors were placed with a transtendinous technique at the anterior and posterior edges of the lesion respecting the tendon insertion to the avulsed fragment. The medial sutures were retrieved through the intact supraspinatus tendon medially to the fracture. The sutures were initially coupled in a double-pulley configuration generating 2 sutures oriented from anterior to posterior; then a simple suture for each anchor oriented from medial to lateral was obtained. At the end of the procedure, the adequacy of reduction and stability of the fragments were confirmed. At 2 months from surgery, radiographic healing of the fracture was noted and integrity of the supraspinatus tendon insertion to the footprint was confirmed by arthro–magnetic resonance imaging, with full recovery of daily activities and complete active range of motion confirmed at 6 and 12 months. The double-pulley technique allows optimal reduction of bony fragments and reconstruction of normal footprint anatomy even in comminuted fractures. Moreover, it creates a waterproof reduction of the fragments, protecting the fracture site from synovial fluid.
Murena, Luigi; Canton, Gianluca; Falvo, Daniele A.; Genovese, Eugenio A.; Surace, Michele F.; Cherubino, Paolo
Purpose. The purpose of this study was to investigate supraspinatus tendon sonographic morphology in a population of young overhead\\u000a athletes in correlation with main pathologic models of secondary shoulder impingement syndrome.\\u000a \\u000a \\u000a \\u000a Subjects and methods. Between April and May 2004, 20 subjects (ten professional basketball players and ten non-athlete controls of the same age,\\u000a weight and height ranges) underwent bilateral, standardised, sonographic sholulder
R. Girometti; A. De Candia; M. Sbuelz; F. Toso; C. Zuiani; M. Bazzocchi
A distinct type of partial-thickness rotator cuff tear has been observed in overhead athletes, characterized by partial failure of the undersurface of the posterior supraspinatus and anterior infraspinatus tendons with intratendinous delamination. We present a technique of percutaneous intratendinous repair using nonabsorbable mattress sutures designed for the management of articular-side delaminated partial-thickness tears. After tear evaluation and preparation, the torn rotator cuff undersurface is held in a reduced position with a grasper through an anterolateral rotator interval portal while viewing intra-articularly. Two spinal needles are then placed percutaneously through the full thickness of the torn and intact rotator cuff. A polydioxanone suture is passed through each needle, retrieved out the anterior portal, and used to shuttle a single nonabsorbable No. 2 suture through the tissue, creating a mattress suture. Multiple mattress sutures can be placed as dictated by tear size and morphology, with suture retrieval and knot securing then proceeding in the subacromial space. We have adopted this approach with the goals of anatomically re-establishing the rotator cuff insertion and sealing the area of intratendinous delamination while preventing significant alteration to the anatomy of the rotator cuff insertion, which could lead to motion deficits, internal impingement, and potential tear recurrence. PMID:18657747
Brockmeier, Stephen F; Dodson, Christopher C; Gamradt, Seth C; Coleman, Struan H; Altchek, David W
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.
Lake, Spencer P.; Miller, Kristin S.; Elliott, Dawn M.; Soslowsky, Louis J.
It was hypothesized that there would be an alteration in strain when macroscopically normal supraspinatus tendons were subjected to three patterns of surgically created tear. The propagation of joint-side partial-thickness tears was also examined. Cadaveric shoulders were tested on a purpose-built rig with static loading from 20 to 200 N and during glenohumeral abduction from 0 degrees to 120 degrees with a 100-N tensile load. Differential variable reluctance transducers were used to calculate strain. Six-millimeter-wide midsubstance full-thickness tears (n = 2) caused an increase in bursal-side strain both with abduction 1.93% (90 degrees ) and with loading 0.33% (150 N). Intratendinous delamination (n = 2) increased joint-side strain during abduction and bursal-side strain with loading. A 2-mm-deep tear across the tendon insertion (n = 5) increased the bursal-side strain in abduction by 3.54% (120 degrees ) and with load by 2.53% (200 N). Tear propagation was observed from joint to bursal sides during abduction. Tendon failure occurred at the insertion. PMID:12700564
Reilly, Peter; Amis, Andrew A; Wallace, Andrew L; Emery, Roger J H
Muscle atrophy and fat accumulation occur after rotator cuff tearing. Whether these changes are reversible after a successful repair is still unknown. Imaging allows only a semi-quantitative assessment of muscle atrophy and fat deposition. As only experimental studies permit a quantification of both, a unilateral detachment and wrapping in a polyvinylidine fluoride membrane of the supraspinatus was done in 22
Fujio Matsumoto; Hans K. Uhthoff; Guy Trudel; Joachim F. Loehr
Shoulders with supraspinatus (SSP) tears are associated with significantly larger critical shoulder angles (CSA) compared to disease-free shoulders. We hypothesized that larger CSAs increase the ratio of joint shear to joint compression forces (defined as "instability ratio"), requiring substantially increased compensatory supraspinatus loads. A shoulder simulator with simulated deltoid, supraspinatus, infraspinatus/teres minor, and subscapularis musculotendinous units was constructed. The model was configured to represent either a normal CSA of 33° or a CSA characteristic of shoulders with rotator cuff tears (38°), and the components of the joint forces were measured. The instability ratio increased for the 38° CSA compared with the control CSA (33°) for a range of motion between 6° to 61° of thoracohumeral abduction with the largest differences in instability observed between 33° and 37° of elevation. In this range, SSP force had to be increased by 13-33% (15-23?N) to stabilize the arm in space. Our results support the concept that a high CSA can induce SSP overload particularly at low degrees of active abduction. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:952-957, 2014. PMID:24700399
Gerber, Christian; Snedeker, Jess G; Baumgartner, Daniel; Viehöfer, Arnd F
PurposeManagement of articular sided partial-thickness rotator cuff tears is controversial. Most management decisions rest on determining the thickness of tendon loss and location of tendon involvement, without any clear guidelines offered on how to make this determination. This study attempts to confirm the normal cuff thickness at its humeral head attachment and correlate the amount of exposed bone at the
Charles Ruotolo; Jonathan E Fow; Wesley M Nottage
Summary 30 MRI investigations of shoulders and 20 dissections of non embalmed cadaveric shoulders allowed us to demonstrate a particular organization of the supraspinatus muscle. In the anterior part of the muscle is an important fibrous frame with obliquely inserted muscle fibers. This organization suggests that this part of the supraspinatus muscle works as a “contractile tendon”.
N Gagey; O Gagey; G Bastian; JP Lassau
A rotator cuff tear (RCT) is a common musculoskeletal disorder among elderly people. RCT is often treated conservatively for functional compensation by the remaining muscles. However, the mode of such compensation after RCT has not yet been fully understood. Here, we used the RCT rat model to investigate the compensatory process in the remaining muscles. The involvement of insulin-like growth factor 1 (IGF-1)/Akt signaling which potentially contributes to the muscle growth was also examined. The RCT made by transecting the supraspinatus (SSP) tendon resulted in atrophy of the SSP muscle. The remaining infraspinatus (ISP) muscle weight increased rapidly after a transient decrease (3 days), which could be induced by posttraumatic immobilization. The IGF-1 mRNA levels increased transiently at 7 days followed by a gradual increase thereafter in the ISP muscle, and those of IGF-1 receptor mRNA significantly increased after 3 days. IGF-1 protein levels biphasically increased (3 and 14 days), then gradually decreased thereafter. The IGF-1 protein levels tended to show a negative correlation with IGF-1 mRNA levels. These levels also showed a negative correlation with the ISP muscle weight, indicating that the increase in IGF-1 secretion may contribute to the ISP muscle growth. The pAkt/Akt protein ratio decreased transiently by 14 days, but recovered later. The IGF-1 protein levels were negatively correlated with the pAkt/Akt ratio. These results indicate that transection of the SSP tendon activates IGF-1/Akt signaling in the remaining ISP muscle for structural compensation. Thus, the remaining muscles after RCT can be a target for rehabilitation through the activation of IGF-1/Akt signaling. PMID:24744876
Ichinose, Tsuyoshi; Lesmana, Ronny; Yamamoto, Atsushi; Kobayashi, Tsutomu; Shitara, Hitoshi; Shimoyama, Daisuke; Takatsuru, Yusuke; Iwasaki, Toshiharu; Shimokawa, Noriaki; Takagishi, Kenji; Koibuchi, Noriyuki
Abstract A rotator cuff tear (RCT) is a common musculoskeletal disorder among elderly people. RCT is often treated conservatively for functional compensation by the remaining muscles. However, the mode of such compensation after RCT has not yet been fully understood. Here, we used the RCT rat model to investigate the compensatory process in the remaining muscles. The involvement of insulin?like growth factor 1 (IGF?1)/Akt signaling which potentially contributes to the muscle growth was also examined. The RCT made by transecting the supraspinatus (SSP) tendon resulted in atrophy of the SSP muscle. The remaining infraspinatus (ISP) muscle weight increased rapidly after a transient decrease (3 days), which could be induced by posttraumatic immobilization. The IGF?1 mRNA levels increased transiently at 7 days followed by a gradual increase thereafter in the ISP muscle, and those of IGF?1 receptor mRNA significantly increased after 3 days. IGF?1 protein levels biphasically increased (3 and 14 days), then gradually decreased thereafter. The IGF?1 protein levels tended to show a negative correlation with IGF?1 mRNA levels. These levels also showed a negative correlation with the ISP muscle weight, indicating that the increase in IGF?1 secretion may contribute to the ISP muscle growth. The pAkt/Akt protein ratio decreased transiently by 14 days, but recovered later. The IGF?1 protein levels were negatively correlated with the pAkt/Akt ratio. These results indicate that transection of the SSP tendon activates IGF?1/Akt signaling in the remaining ISP muscle for structural compensation. Thus, the remaining muscles after RCT can be a target for rehabilitation through the activation of IGF?1/Akt signaling.
Ichinose, Tsuyoshi; Lesmana, Ronny; Yamamoto, Atsushi; Kobayashi, Tsutomu; Shitara, Hitoshi; Shimoyama, Daisuke; Takatsuru, Yusuke; Iwasaki, Toshiharu; Shimokawa, Noriaki; Takagishi, Kenji; Koibuchi, Noriyuki
Although the incidence of partial-thickness rotator cuff tears (PTRCTs) was reported to be from 13% to 32% in cadaveric studies, the actual incidence is not yet known. The causes of PTRCTs can be explained by either extrinsic or intrinsic theories. Studies suggest that intrinsic degeneration within the rotator cuff is the principal factor in the pathogenesis of rotator cuff tears. Extrinsic causes include subacromial impingement, acute traumatic events, and repetitive microtrauma. However, acromially initiated rotator cuff pathology does not occur and extrinsic impingement does not cause pathology on the articular side of the tendon. An arthroscopic classification system has been developed based on the location and depth of the tear. These include the articular, bursal, and intratendinous areas. Both ultrasound and magnetic resonance image are reported with a high accuracy of 87%. Conservative treatment, such as subacromial or intra-articular injections and suprascapular nerve block with or without block of the articular branches of the circumflex nerve, should be considered prior to operative treatment for PTRCTs.
Two dogs with supraspinatus calcifying tendinopathy were lame in their forelimbs and were treated by the surgical excision of the calcified lesion. The lameness in both dogs improved after surgery without additional medical treatment, as evidenced by force-plate analysis of their gait.
P. Muir; K. A. Johnson; A. J. Cooley; P. A. Manley
Heat shock proteins (HSPs) are often upregulated following oxidative and other forms of stress. Based on reports of excessive\\u000a apoptosis in torn supraspinatus tendon and mechanically loaded tendon cells, we hypothesized heat shock proteins may be present\\u000a in rodent and human models of tendinopathy due to their central role in caspase dependent apoptotic cell signaling. We used\\u000a a running rat
Neal L. Millar; Ai Q. Wei; Timothy J. Molloy; Fiona Bonar; George A. C. Murrell
The muscles and tendons of the rotator cuff of 37 fixed cadaver shoulder joints were dissected. In ten shoulder joints devoid of gross pathological lesions it was found that the supraspinatus muscle was inserted at two points — mainly into the major tubercle and partly into the lesser tubercle of the humerus. In one case of six, an additional insertion
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
Zilber, Sébastien; Carillon, Yannick; Lapner, Peter C; Walch, Gilles; Nové-Josserand, Laurent
Tendinopathy and small partial-thickness tears of the rotator cuff tendon are common presentations in sports medicine. No promising treatment has yet been established. Corticosteroid injections may improve symptoms in the short term but do not primarily treat the tendon pathology. Ultrasound-guided autologous tenocyte implantation (ATI) is a novel bioengineered treatment approach for treating tendinopathy. We report the first clinical case of ATI in a 20-year-old elite gymnast with a rotator cuff tendon injury. The patient presented with 12 months of increasing pain during gymnastics being unable to perform most skills. At 1 year after ATI the patient reported substantial improvement of clinical symptoms. Pretreatment and follow-up MRIs were reported and scored independently by two experienced musculoskeletal radiologists. Tendinopathy was improved and the partial-thickness tear healed on 3 T MRI. The patient was able to return to national-level competition. PMID:23314880
Wang, Allan W; Bauer, Stefan; Goonatillake, Matthew; Breidahl, William; Zheng, Ming-Hao
Microbial cellulose is a natural polymer that can hold an quantity of water without any disconformities. As a result it is considered to be a wound-dressing material. We report a case of 28% total body surface area partial-thickness flame burn, approximately 4.5% superficial partial-thickness burns on anterior face, and 23.5% mixed, between superficial and deep partial-thickness burns, on both upper
Pornprom Muangman; Supaporn Opasanon; Supaparn Suwanchot; Orapin Thangthed
Summary Axial MR images of the shoulder joint reveal a central linear band within the supraspinatus muscle void of signal which seems not to represent the only tendon of this muscle. Due to the importance of the supraspinatus muscle for the painful impingement syndrome of the shoulder we studied the fibrous architecture of this muscle comparing 30 MR images and
M Vahlensieck; K an Haack; H-M Schmidt
A rotator cuff tear causes morphologic changes in rotator cuff muscles and tendons and reduced shoulder strength. The mechanisms by which these changes affect joint strength are not understood. This study's purpose was to empirically determine rotation moment arms for subregions of supraspinatus, infraspinatus, and for teres minor, and to test the hypothesis that subregions of the cuff tendons increase
Joseph E. Langenderfer; Cameron Patthanacharoenphon; James E. Carpenter; Richard E. Hughes
Purpose. The purpose of this study was to compare the accuracy of the conventional method for determining the percentage of partial thickness rotator cuff tears to a method using an intra-articular depth guide. The clinical utility of the intra-articular depth guide was also examined. Methods. Partial rotator cuff tears were created in cadaveric shoulders. Exposed footprint, total tendon thickness, and percentage of tendon thickness torn were determined using both techniques. The results from the conventional and intra-articular depth guide methods were correlated with the true anatomic measurements. Thirty-two patients were evaluated in the clinical study. Results. Estimates of total tendon thickness (r = 0.41, P = 0.31) or percentage of thickness tears (r = 0.67, P = 0.07) using the conventional method did not correlate well with true tendon thickness. Using the intra-articular depth guide, estimates of exposed footprint (r = 0.92, P = 0.001), total tendon thickness (r = 0.96, P = 0.0001), and percentage of tendon thickness torn (r = 0.88, P = 0.004) correlated with true anatomic measurements. Seven of 32 patients had their treatment plan altered based on the measurements made by the intra-articular depth guide. Conclusions. The intra-articular depth guide appeared to better correlate with true anatomic measurements. It may be useful during the evaluation and development of treatment plans for partial thickness articular surface rotator cuff tears.
Carroll, Michael J.; More, Kristie D.; Sohmer, Stephen; Nelson, Atiba A.; Sciore, Paul; Boorman, Richard; Hollinshead, Robert; Lo, Ian K. Y.
The muscles and tendons of the rotator cuff of 37 fixed cadaver shoulder joints were dissected. In ten shoulder joints devoid of gross pathological lesions it was found that the supraspinatus muscle was inserted at two points--mainly into the major tubercle and partly into the lesser tubercle of the humerus. In one case of six, an additional insertion clearly occurred in a shoulder joint with rotator cuff tear. PMID:1389774
Objective. The purpose of this study was to analyze the effects of the procedure of superior transposition of the subscapularis on the biomechanics of glenohumeral abduction.Design. The abduction moment arms of the subscapularis muscle for the normal attachment and transposed tendon were measured on 10 cadaver shoulders and compared to that for the normal supraspinatus tendon for which it is
Tomotaka Nakajima; Jain Liu; Richard E. Hughes; Shawn O'Driscoll; Kai-Nan An
Objective. To determine why certain tendon transfers are mechanically more effective than other tendon transfers for the treatment of a massive rotator cuff tear.Design. A tendon transfer procedure of latissimus dorsi, teres major or a combination of these two to the insertions of either teres minor, infraspinatus, supraspinatus, or subscapularis is simulated using a biomechanical musculoskeletal model of the upper
D. J. Magermans; E. K. J. Chadwick; H. E. J. Veeger; P. M. Rozing
A rotator cuff tear causes morphologic changes in rotator cuff muscles and tendons and reduced shoulder strength. The mechanisms by which these changes affect joint strength are not understood. This study's purpose was to empirically determine rotation moment arms for subregions of supraspinatus, infraspinatus, and for teres minor, and to test the hypothesis that subregions of the cuff tendons increase their effective moment arms through connections to other subregions. Tendon excursions were measured for full ranges of rotation on 10 independent glenohumeral specimens with the humerus abducted in the scapular plane at 10 and 60 degrees . Supraspinatus and infraspinatus tendons were divided into equal width subregions. Two conditions were tested: tendon divided to the musculotendinous junction, and tendon divided to the insertion on the humerus. Moment arms were determined from tendon excursion via the principle of virtual work. Moment arms for the infraspinatus (p < 0.001) and supraspinatus (p < 0.001) were significantly greater when the tendon was only divided to the musculotendinous junction versus division to the humeral head. Moment arms across subregions of infraspinatus (p < 0.001) and supraspinatus (p < 0.001) were significantly different. A difference in teres minor moment arm was not found for the two cuff tendon conditions. Moment arm differences between muscle subregions and for tendon division conditions have clinical implications. Interaction between cuff regions could explain why some subjects retain strength after a small cuff tear. This finding helps explain why a partial cuff repair may be beneficial when a complete repair is not possible. Data presented here can help differentiate between cuff tear cases that would benefit from cuff repair and cases for which cuff repair might not be as favorable. PMID:16779813
Langenderfer, Joseph E; Patthanacharoenphon, Cameron; Carpenter, James E; Hughes, Richard E
A rotator cuff tear causes morphologic changes in rotator cuff muscles and tendons and reduced shoulder strength. The mechanisms by which these changes affect joint strength are not understood. This study’s purpose was to empirically determine rotation moment arms for subregions of supraspinatus, infraspinatus, and for teres minor, and to test the hypothesis that subregions of the cuff tendons increase their effective moment arms through connections to other subregions. Tendon excursions were measured for full ranges of rotation on 10 independent glenohumeral specimens with the humerus abducted in the scapular plane at 10 and 60°. Supraspinatus and infraspinatus tendons were divided into equal width subregions. Two conditions were tested: tendon divided to the musculotendinous junction, and tendon divided to the insertion on the humerus. Moment arms were determined from tendon excursion via the principle of virtual work. Moment arms for the infraspinatus (p < 0.001) and supraspinatus (p < 0.001) were significantly greater when the tendon was only divided to the musculotendinous junction versus division to the humeral head. Moment arms across subregions of infraspinatus (p < 0.001) and supraspinatus (p < 0.001) were significantly different. A difference in teres minor moment arm was not found for the two cuff tendon conditions. Moment arm differences between muscle subregions and for tendon division conditions have clinical implications. Interaction between cuff regions could explain why some subjects retain strength after a small cuff tear. This finding helps explain why a partial cuff repair may be beneficial when a complete repair is not possible. Data presented here can help differentiate between cuff tear cases that would benefit from cuff repair and cases for which cuff repair might not be as favorable.
Langenderfer, Joseph E.; Patthanacharoenphon, Cameron; Carpenter, James E.; Hughes, Richard E.
We evaluated the use of Suprathel(®), a synthetic skin substitute, for partial thickness burns in children. Thirty-three children (20 females, 13 males; mean age 29 months, range 5 months to 11 years) with burns were treated with Suprathel(®). The burns were superficial partial thickness (n=24) or mid-dermal (n=19); the median %TBSA was 4% (range 1-13%). Suprathel(®) was applied after debridement, followed by Vaseline gauze, dry gauze and crepe bandage. The outer dressings were changed every 5-10 days unless clinical problems dictated otherwise. Median healing time was 16 days (range 9-38 days). Ten patients took longer than 21 days to heal, of whom four developed hypertrophic scarring, which was strongly associated with wound infection (p<0.05). Healing time of superficial partial thickness and mid-dermal burns was not significantly different (p=0.494). Suprathel(®) is an effective skin substitute for the treatment of partial thickness burns in children. The majority of burns in children are mixed depth, and Suprathel(®) has the advantage that it may also be used to treat mid-dermal burns. It behaves like a biological dressing but is not animal derived, so is acceptable to all religious and ethnic groups. Further studies to evaluate the efficacy and cost effectiveness of Suprathel(®) compared to other dressings in children are warranted. PMID:22698841
Highton, Lyndsey; Wallace, Christopher; Shah, Mamta
Simple burn wound models are always warranted. In view of this a partial thickness reproducible 2 degrees C burn wound has been produced using hot molten wax. This model is simple, convenient, and could be used to monitor wound contraction and epithelization in burn wounds. PMID:9279135
Bairy, K L; Somayaji, S N; Rao, C M
Objective: To describe the evaluation, management, and rehabilitation of an acute, supraspinatus tendon injury in an intercollegiate football player. Background: While attempting to block a defender, a 19-year-old collegiate football player slipped on the artificial turf and landed on his right elbow, causing an injury to his right shoulder. The athlete was initially seen by the head athletic trainer and then referred to the team physician for further evaluation. Differential Diagnosis: acromioclavicular joint sprain, brachial plexopathy, subacromial impingement syndrome, supraspinatus lesion. Treatment: The athlete was managed surgically with an open acromioplasty and a 3-bone tunnel repair of the supraspinatus tendon. After surgery, the athlete underwent a 4-month rehabilitation protocol in preparation for return to competition. Uniqueness: This case involved a teenage athlete rather than the older individuals who normally sustain rotator cuff lesions. Also, the mechanism was a compressive force on the supraspinatus tendon rather than the tensile force common to rotator cuff lesions. Conclusions: By presenting this case report, we hope to give sports medicine clinicians a better understanding of rotator cuff injuries and how to successfully manage and rehabilitate supraspinatus lesions. ImagesFigure 1.Figure 2.
Gorse, Keith M.; Myers, Joseph B.; Radelet, Marirose; Scovazzo, Mary Lynn; D'Alessandro, Donald
Three muscles from the proximal equine forelimb were dissected in order to investigate their potential to contribute to proximal limb mechanics. Muscle mass, fibre length, tendon mass and tendon length were measured from biceps brachii, triceps brachii, supraspinatus and lacertus fibrosus (biceps lateral head mass 171-343.4 g and fibre length 0.5-0.8 cm; biceps medial head mass 283-500 g and fibre length 2.2-4 cm; biceps tendon mass 121.8-260 g and tendon length 35-44 cm; triceps long head mass 3200-6663 g and fibre length 19-26.3 cm; triceps lateral head mass 513.8-1240 g and fibre length 17.5-24 cm; triceps medial head mass 85.2-270.6 g and fibre length 9-16.8 cm; supraspinatus mass 793-1546 g and fibre length 4.7-12.4 cm; lacertus fibrosus mass 4.6-12.4 g and length 10-16 cm). Physiological cross-sectional area (PCSA) and maximum isometric force were estimated for each muscle, and moment arm measurements were taken at the shoulder and elbow joints. Biceps has a greater isometric force-generating capacity than supraspinatus. It also appears to have a larger shoulder moment arm, so could therefore have the potential to make a greater contribution to the shoulder moment than supraspinatus. Supraspinatus is likely to function primarily as a shoulder stabilizer rather than a shoulder extensor. Biceps also functions as an elbow flexor and data here indicate that it has a greater PCSA and isometric force-generating capacity than its antagonist triceps brachii. Calculation of tendon forces showed that the biceps tendon can withstand much greater forces than lacertus fibrosus. This study will enable further investigation into the interaction between energy recycling in elastic tissues and the generation and absorption of mechanical work by adjacent muscle groups in the equine forelimb. PMID:17229281
Watson, J C; Wilson, A M
Summary. This review is based on 66 patients with partial-thickness tears of the rotator cuff, verified at operation. Their average\\u000a age was 54 years, and all had symptoms of subacromial impingement. The duration of shoulder pain was for between 2 and 108\\u000a months (mean 11.4 months). Ultrasonography, arthrography and bursography were helpful in establishing the diagnosis. On exploration,\\u000a tears were
H. Fukuda; K. Hamada; T. Nakajima; N. Yamada; A. Tomonaga; M. Goto
OBJECTIVE: To evaluate the therapeutic effect of the herbal plaster Tangshangxiaobagao on partial thickness burn wound. METHODS: A randomized controlled trial was conducted with two herbal plasters: Tangshang-xiaobagao and Jingwanhong in 57 hospitalized burn patients. Both the effect and safety of two herbal plasters were noted in patients with partial thickness burns. RESTULTS: In superficial second degree burns, the 7 d healing rate of both groups was (61.35+/-36.26)%and (51.21+/-37.24)% and the healing time (10.56+/-3.43)d and (11.98+/-4.13)d P<0.05 respectively. While in deep second degree burns, the 14 d healing rate of both groups was (62.9+/-36.0) % and (53.9+/-32.2) % and the healing time (19.4+/-4.9)d and (21.5+/-5.5)d, respectively. Study group had lower VAS(visual analogue scale)score than control group. No obvious side effects were observed in study group. CONCLUSION: Tangshangxiaobagao is safe and may be an effective adjunct for treatment of partial thickness burn wounds. PMID:12601888
Hu, Xue-Qing; Tao, Yu-Juan; Xu, Jun; Chen, Guo-Xian; Pu, Shu-Song
An important factor in the healing of superficial and moderate partial thickness burn is early and effective coverage with a dressing that protects the wound from trauma and dessication and is non-adherent. In our country cost is also a very important factor. Disturbed by the pain and anxiety experienced by the patients during and after dressing changes, search for a new dressing material was begun for partial thickness burn wounds and the banana leaf dressing (BLD) was subsequently developed and optimised by June 1996. An open controlled study was carried out to compare banana leaf dressing and boiled potato peel bandage (BPPB), the dressing being used in our Burn Unit since 1994. Thirty patients all less than 40 years of age, with burn size less than 50% TBSA, involving comparable body areas with partial thickness burn, were included in the study. BLD along with a topical agent was applied over the right sided extremity while BPPB was applied with the same topical agent on the left sided extremity. Dressing was changed every day. The pain during dressing change, feeling of comfort and ease of handling dressing was assessed by awarding scores by the patients and care givers for each type of dressing. Analysis of the scores revealed that both BLD and BPPB caused easily tolerable, minimal pain during dressing change in majority of the patients. The days taken for epithelialisation, eschar formation and the need for skin grafting over deep partial thickness burns, did not reveal any significant difference between the areas treated by BLD and those by BPPB. So both the dressings were observed to have equal efficacy in protecting the wounds and aiding healing. Thus, the efficacy of BLD and BPPB was parallel in all respects. But BLD is 11 times cheaper than BPPB. Banana plants can be easily grown, the leaves are easily available throughout the year. The leaves of banana are large thus offering larger surface area and the surface is non-adherent, waxy and cool. The dressing can be prepared very easily with little training. It is also the cheapest dressing available today. We strongly recommend the use of banana leaf dressing for all partial thickness burn wounds in our environment. PMID:12880731
Gore, Madhuri A; Akolekar, Deepika
Calcific tendonitis, or calcifying tendonitis, is a common disorder characterized by the multifocal accumulation of basic calcium phosphate crystals within the rotator cuff tendons. In most cases, the multifocal calcifications are located 1 to 2 cm from the insertion of the supraspinatus tendon on the greater tuberosity. The initial treatment should be nonoperative including oral anti-inflammatory medication and physical therapy. If this is unsuccessful, arthroscopic debridement of the deposit is effective. The technique used is an arthroscopic localization and debridement without associated subacromial decompression. The rotator cuff should be evaluated for partial- and full-thickness tears before and after the debridement of calcifications. If a partial- or full-thickness rotator cuff tendon tear is identified, it should be treated in a fashion consistent with those without associated calcium deposits. In our hands, tears 5 mm or greater in depth are repaired using a tendon-to-tendon or tendon-to-bone technique. Tears with less depth are debrided and then left alone. Arthroscopic debridement of calcific tendonitis can yield excellent functional results and high patient satisfaction.
Barber, F. Alan; Cowden, Courtney H.
Calcific tendonitis, or calcifying tendonitis, is a common disorder characterized by the multifocal accumulation of basic calcium phosphate crystals within the rotator cuff tendons. In most cases, the multifocal calcifications are located 1 to 2 cm from the insertion of the supraspinatus tendon on the greater tuberosity. The initial treatment should be nonoperative including oral anti-inflammatory medication and physical therapy. If this is unsuccessful, arthroscopic debridement of the deposit is effective. The technique used is an arthroscopic localization and debridement without associated subacromial decompression. The rotator cuff should be evaluated for partial- and full-thickness tears before and after the debridement of calcifications. If a partial- or full-thickness rotator cuff tendon tear is identified, it should be treated in a fashion consistent with those without associated calcium deposits. In our hands, tears 5 mm or greater in depth are repaired using a tendon-to-tendon or tendon-to-bone technique. Tears with less depth are debrided and then left alone. Arthroscopic debridement of calcific tendonitis can yield excellent functional results and high patient satisfaction. PMID:24904767
Barber, F Alan; Cowden, Courtney H
Rotator cuff tears are a major cause of morbidity. Following rotator cuff tears, muscle atrophy and fatty infiltration begin in the tissue, limiting repair potential and leading to a higher re-tear rate and a worse functional outcome. We evaluated whether fatty degeneration resulting from a complete supraspinatus tear with retraction is associated with an injury to the suprascapular nerve. Four skeletally mature New Zealand white rabbits were randomized to receive an index procedure on either their right or left shoulder with the opposite shoulder serving as a control. At the index procedure, the supraspinatus tendon was transected at its insertion and allowed to retract. At 3 months, the rabbits were euthanized, and both supraspinatus muscles were harvested. The specimens were then examined with confocal microscopy and histology. Atrophy was grossly visible in all four test muscles, and fatty infiltration was confirmed with osmium tetroxide staining. In all four rabbits, the degree of denervation (p?=?0.71) and partial denervation (p?=?0.91) was not significantly different between control and experimental muscle. Rotator cuff tear does not affect the motor endplate or innervation status of the supraspinatus. Fatty infiltration occurs independent of denervation of the supraspinatus. PMID:22836785
Gayton, J Christopher; Rubino, L Joseph; Rich, Mark M; Stouffer, Mark H; Wang, Qingbo; Boivin, Gregory P
Swine are the preferred animal models to study the effects of burns on dermal wound healing. Various studies have been published in which little emphasis was placed on minimizing burn variability and inconsistency. We developed a novel method to create deep partial thickness burns that are highly consistent. A custom-made burn device was fabricated to control the pressure applied on the swine skin during burn creation. Cylindrical brass blocks, measuring 3 cm in diameter, are used to create the burns. A stainless steel post extends from the block for insertion into the device holder. In this study, burns were created in four female Yorkshire swine. Heating of the brass blocks was conducted using a boiling azeotropic solution of 80% polyethylene glycol (PEG) and 20% water and boiling water alone. Contact times ranging from 12 to 20 s were used. At 24 h and 7 d post-injury, two swine were euthanized and tissues collected for digital image evaluation and histological assessment using Gomori trichrome staining. Digital image analysis showed inconsistent healing in burns created using boiling water as compared to the boiling PEG:H(2)O solution. Additionally, histological analyses showed that burns created using boiling water were superficial and more variable compared to those created using the boiling PEG:H(2)O solution. With a burn contact time of 20 s, 48.5±5.7% tissue damage was demonstrated at 24 h when the PEG:H(2)O solution was used, whereas only 11.9±1.3% was observed with boiling water. PMID:22981797
Gaines, Carmen; Poranki, Deepika; Du, Wei; Clark, Richard A F; Van Dyke, Mark
Microbial cellulose is a natural polymer that can hold a quantity of water without any disconformities. Therefore, it is proposed for use as wound dressing material. We report a case of 28% total body surface area partial-thickness flame burn: approximately 4.5% superficial partial-thickness burns on anterior face and 23.5% combined superficial and deep partial-thickness burns on both upper arms and
Pornprom Muangman; Supaporn Opasanon; Supaparn Suwanchot; Orapin Thangthed
Purpose: To evaluate the effect of monopolar radiofrequency (RF) energy on partial-thickness defects of articular cartilage, comparing the outcome of partial-thickness defects treated with monopolar RF energy with that of treatment by conversion of partial-thickness defects to full-thickness defects by curettage and microfracture. Type of Study: Randomized trial using adult female sheep. Materials and Methods: Thirty-six sheep were used in
Yan Lu; Kei Hayashi; Paul Hecht; Gary S. Fanton; George Thabit; A. J. Cooley; Ryland B. Edwards; Mark D. Markel
The collagen composition of the supraspinatus, infraspinatus, and subscapularis tendons, which form part of the rotator cuff of the shoulder, was determined. Tendons were obtained from adult, male beagle dogs and total collagen was estimated by measurement of hydroxyproline. There was little variation in collagen content among the three major cuff tendons and the quantity approximated that cited in the literature for other tendons. However, the collagen content in the insertion zone of the supraspinatus tendon was significantly higher than in the tendon proper. NaCl fractionation of supraspinatus collagen indicated that type I was the predominant collagen but significant amounts of type III and possibly some type II and type V were also present. Interestingly, there appeared to be more type III collagen in the insertion zone than in the tendon proper, cyanogen bromide digestion and peptide mapping confirmed this finding. The differential collagen composition of the supraspinatus tendon may contribute to the high incidence of tear that is associated with this rotator cuff tendon. PMID:9262514
Fan, L; Sarkar, K; Franks, D J; Uhthoff, H K
Purpose: Partial-thickness articular-sided rotator cuff tears have a multifactorial etiology and are associated with degeneration of the tendon. They are often described as an injury of the young athlete, although they are also found in the older population. The aim of this study was to investigate the frequency and associations of partial-thickness articular-sided tears in patients over the age of 35 years. Design: Retrospective Materials and Methods: A retrospective study of all arthroscopic procedures for rotator cuff pathology in patients over the age of 35 years over a 2-year period by a single surgeon was performed. The included patients were divided into two groups based on the arthroscopic findings: those with a partial-thickness articular-sided rotator cuff tear and those with pure tendinopathy. The groups were then compared to identify the associated pathology with the rotator cuff lesions. 2×2 contingency table analysis and unpaired Student's t-test were used for statistical analysis. Results: One hundred patients were included in the study of whom 62 had a partial articular-sided tear. Those with a partial articular-sided tear were older (P=0.0001), were more commonly associated with a documented injury (P=0.03), and more commonly had biceps degeneration (P=0.001) and synovitis (P=0.02) within the joint. Conclusion: Partial-thickness articular-sided tears are a common occurrence in patients requiring arthroscopic surgery for rotator cuff pathology over the age of 35 years. This probably reflects an injury in an already degenerate cuff. This would support the theory of intrinsic degeneration of the tendon in this age group and probably represent a different etiology to those seen in the young athletes. Level of Evidence: Level 3
Modi, Chetan S; Smith, Christopher D; Drew, Stephen J
The human supraspinatus muscle is clinically important as it is frequently injured in older adults and the elderly. We have previously shown that the supraspinatus has a complex architecture with two distinct regions each consisting of three parts. Further we have found dynamic changes in architectural parameters such as fiber bundle length markedly vary between these regions. Fiber types of the supraspinatus have not been thoroughly investigated throughout its volume and are of interest to clinicians treating supraspinatus pathologies. In this study we investigated the distribution of fiber types within the distinct regions and parts of supraspinatus. Samples of supraspinatus were excised from six distinct parts of each muscle from five formalin embalmed specimens (one male, four female; mean age 77±11.1 years) free of tendon pathology. Samples were frozen in liquid nitrogen and then cryosectioned. Serial sections were labeled using immunohistochemical techniques and antibodies against fast or slow myosin heavy chain isoforms. The mean percentage of Type I (slow) fibers ranged from 56.73% to 63.97%. Results demonstrated significant variations in fiber type distribution. The middle part of the anterior region has a significantly greater percentage of Type I fibers compared to that of the posterior. The superficial part of the anterior region has a greater percentage of Type II (fast) fibers compared to the middle and deep parts. Findings aid in highlighting the distinct functions of the anterior and posterior regions, and prompt the need to re-evaluate assessment and treatment techniques established on a limited understanding of the fiber type distribution. PMID:23463598
Kim, S Y; Lunn, D D; Dyck, R J; Kirkpatrick, L J; Rosser, B W C
Objective. To determine what the most effective tendon transfer is in the case of a dysfunctional rotator cuff.Design. A tendon transfer procedure of latissimus dorsi, teres major or a combination of these two to the insertions of either teres minor, infraspinatus, supraspinatus, or subscapularis is simulated using a biomechanical musculoskeletal model of the upper extremity.Background. Massive rotator cuff tears are
D. J. Magermans; E. K. J. Chadwick; H. E. J. Veeger; P. M. Rozing; F. C. T van der Helm
The pathophysiology of rotator cuff tears can be elucidated by examining the tendinous insertion of the supraspinatus muscle. As seen by light microscopy, the granulation tissue around the insertion of a torn supraspinatus tendon appears to induce osteochondral destruction by means of multinucleated giant cells and chemical mediators. The purpose of this study was to examine the contribution of certain chemical mediators to osteochondral destruction using immunohistochemical analysis of interleukin-beta, cathepsin D, and matrix metalloprotease-1. Sixteen supraspinatus insertions with portions of the greater tuberosity, including eight complete-thickness tears and eight incomplete-thickness tears, were obtained during surgery. Six fresh cadaveric supraspinatus tendons without grossly evident tears served as normal controls. Strong immunoreactivity was found in all 16 torn supraspinatus insertions but not in the six insertions of apparently intact tendons. Macrophages and multinucleated giant cells, which showed immunoreactivity for all three chemical mediators, were often found at the interface between the osteochondral margin of the enthesis and the granulation tissue, suggesting that they may be involved in osteochondral destruction. We therefore concluded that, in addition to repetitive subacromial impingement, this granulation tissue may contribute to the development of rotator cuff tears by weakening the insertion. PMID:9066524
Gotoh, M; Hamada, K; Yamakawa, H; Tomonaga, A; Inoue, A; Fukuda, H
Drugs hypersensitivity should be remembered when placing patients on any form of medications. In this case we present skin hypersensitivity to sun light due to doxycycline ingestion causing hand partial-thickness burn.
Simman, Richard; Raynolds, David
Microbial cellulose is a natural polymer that can hold a quantity of water without any disconformities. Therefore, it is proposed for use as wound dressing material. We report a case of 28% total body surface area partial-thickness flame burn: approximately 4.5% superficial partial-thickness burns on anterior face and 23.5% combined superficial and deep partial-thickness burns on both upper arms and anterior trunk. A microbial cellulose dressing, Nanocell (Thai Nano Cellulose Co Ltd, Bangkok, Thailand), was applied to the face wound only once, without any further dressing change. Progress of healing, until full epithelialization on the face, was observed for 2 weeks. During the treatment period, the patient did not show any irritation or allergic reaction to this new dressing, and wound swab culture showed no evidence of bacteria presence. This innovative material can be an alternative dressing for superficial partial-thickness burn wounds.
Muangman, Pornprom; Opasanon, Supaporn; Suwanchot, Supaparn; Thangthed, Orapin
Summary In laser-induced partial-thickness burns of pig skin, moist exposed burn ointment (MEBO) produces a moist environment, allows drainage of exudates, reduces eschar formation, and accelerates debridement and wound healing. A prospective multi-center study was conducted to evaluate the effect of MEBO on the healing of partial-thickness burn wounds. We included 52 patients with 100 burn sites ranging from 0.5% to
J. D. Ioannovich; G. Magliacani; M. Costagliola; B. Attiyeh; R. Dahm; A. Berger; M. Masselis; A. Gravvanis
. The collagen composition of the supraspinatus, infraspinatus, and subscapularis tendons, which form part of the rotator cuff\\u000a of the shoulder, was determined. Tendons were obtained from adult, male beagle dogs and total collagen was estimated by measurement\\u000a of hydroxyproline. There was little variation in collagen content among the three major cuff tendons and the quantity approximated\\u000a that cited in
L. Fan; K. Sarkar; D. J. Franks; H. K. Uhthoff
We determined on histologic examination the degree of degeneration at the insertion of 3 rotator cuff tendons in 76 cadaveric shoulders, 17 of which had a partial tear of the supraspinatus. Fiber thinning, the presence of granulation tissue, and incomplete tearing of fibers, all evidence of degeneration, were quantified separately for each tendon. Among the shoulders that were intact on
Hirotaka Sano; Hirotada Ishii; Guy Trudel; Hans K Uhthoff
To develop a method of tendon attachment to a metallic endoprosthesis, we evaluated fixation strength, clinical function of the tendon, and morphological changes in an experimental model. The canine supraspinatus tendon was removed from the greater tubercle of the humerus and attached to a titanium prosthesis. In 12 animals, the bone block underlying the tendon insertion was preserved and attached in one limb; the soft part of the tendon was attached directly to the prosthesis in the contralateral limb. Fixation strength was evaluated after 16 weeks of in vivo implantation (12 specimens) and compared with the in vitro fixation strength (12 specimens) and with intact normal controls (six specimens from cadavera). Function of the tendon in vivo was evaluated by force-plate analysis (at 3-week intervals). All specimens were evaluated histologically. Sixteen weeks after surgery, the tendon-bone block attachment was significantly stronger (mean, 16%) than the direct tendon attachment and not significantly different from the normal control, and the direct tendon attachment was significantly weaker (mean, 68%) than the normal control. There was significantly more weight-bearing on the limbs with a tendon-bone block attachment than on the limbs with a direct tendon attachment at both 3 and 6 weeks postoperatively. Both front legs showed increased weight-bearing with time, but the differences were not statistically significant. Anchorage by tissue ingrowth to the titanium prosthesis was found consistently--there was bone ingrowth in the tendon-bone block attachments and fibrous tissue ingrowth in the direct tendon attachments. When a bone block was preserved, the strength and stiffness were comparable with those of a normal tendon insertion.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7983557
Gottsauner-Wolf, F; Egger, E L; Schultz, F M; Sim, F H; Chao, E Y
Background Chronic rotator cuff tears are often associated with pain or poor function. In a rat with only a detached supraspinatus tendon,\\u000a the tendon heals spontaneously which is inconsistent with how tears are believed to heal in humans.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes We therefore asked whether a combined supraspinatus and infraspinatus detachment in the rat would fail to heal and result\\u000a in a chronic injury
LeAnn M. Dourte; Stephanie M. Perry; Charles L. Getz; Louis J. Soslowsky
Reconstruction of partial-thickness defects of the cheek can be challenging. In addition to maintaining function, the repair must restore contour, minimise donor-site deformity and not distort the eyelid, mouth or jaw line. Since the demands for repair differ according to the site, so do the reconstructive options. To aid in selecting the best method, we classify the cheek into five
R. Y. Chandawarkar; A. L. Cervino
Allografts, cadaver skin and amnion membrane are considered the golden standard in the management of partial thickness burns. However, debate on whether the tissue needs to be viable is on-going, since many believe that viable grafts result in better healing. The objective of this literature survey was to analyse the evidence on the method of preservation of allografts (cadaver skin or amnion membrane, glycerol, cryopreservation, lyophilisation) having a clinical impact on the healing of partial thickness burns. The survey focussed on preservation techniques and clinical outcomes (reepithelialisation) in partial thickness burns, as well as on differences in viability, immunogenicity and antimicrobial properties of the preservation methods. Most studies on allograft treatment of partial thickness burns are observational, with only one study of a (historical) comparative nature. A true meta-analysis was not performed and the results of this survey are observational in nature as well: they indicate that there is no evidence that viability of the graft influences healing outcomes. Thus, instead of viability, other aspects, such as intrinsic antimicrobial safety of the preservation method and cost should be the primary criteria for the choice of preservation method to be used for allografts. PMID:21353745
Hermans, Michel H E
Summary We evaluated whether matrix metalloproteases and their inhibitors are involved in extracellular matrix remodelling and degradation of chronic rotator cuff tears. Tendon samples were harvested from 13 patients who underwent arthroscopic repair of a rotator cuff tear. Supraspinatus specimens were harvested en bloc from the arthroscopically intact middle portion of the tendon, more than 1 cm lateral to the torn edge, from the lateral edge of the tear, and from the superior margin of the macroscopically intact subscapularis tendon, used as control. The collagenases, the stromelysins, and the tissue inhibitors of metalloprotease arrays were analyzed blindly by multiplex sandwich ELISA in each specimen. Histological evidence of tendinopathy was present in all patients with a rotator cuff tear, but not in the macroscopically intact subscapularis tendon. There were significantly increased levels of MMP 1, MMP 2, MMP 3, TIMP-1, and TIMP-2 in all specimens examined, including the macroscopically intact portion of the supraspinatus tendon and the subscapularis (control specimens). The levels of specific matrix metalloproteases and their inhibitors are altered in torn rotator cuff tendons, but also in the macroscopically and histologically intact tendons. These changes extended medially to the site of tendon tear, and to other tendons.
Castagna, Alessandro; Cesari, Eugenio; Garofalo, Raffaele; Gigante, Antonio; Conti, Marco; Markopoulos, Nikolaos; Maffulli, Nicola
We evaluated whether matrix metalloproteases and their inhibitors are involved in extracellular matrix remodelling and degradation of chronic rotator cuff tears. Tendon samples were harvested from 13 patients who underwent arthroscopic repair of a rotator cuff tear. Supraspinatus specimens were harvested en bloc from the arthroscopically intact middle portion of the tendon, more than 1 cm lateral to the torn edge, from the lateral edge of the tear, and from the superior margin of the macroscopically intact subscapularis tendon, used as control. The collagenases, the stromelysins, and the tissue inhibitors of metalloprotease arrays were analyzed blindly by multiplex sandwich ELISA in each specimen. Histological evidence of tendinopathy was present in all patients with a rotator cuff tear, but not in the macroscopically intact subscapularis tendon. There were significantly increased levels of MMP 1, MMP 2, MMP 3, TIMP-1, and TIMP-2 in all specimens examined, including the macroscopically intact portion of the supraspinatus tendon and the subscapularis (control specimens). The levels of specific matrix metalloproteases and their inhibitors are altered in torn rotator cuff tendons, but also in the macroscopically and histologically intact tendons. These changes extended medially to the site of tendon tear, and to other tendons. PMID:24367772
Castagna, Alessandro; Cesari, Eugenio; Garofalo, Raffaele; Gigante, Antonio; Conti, Marco; Markopoulos, Nikolaos; Maffulli, Nicola
Summary The structure of a tendon is an important example of complexity of ECM three-dimensional organization. The extracellular matrix (ECM) is a macromolecular network with both structural and regulatory functions. ECM components belong to four major types of macromolecules: the collagens, elastin, proteoglycans, and noncollagenous glycoproteins. Tendons are made by a fibrous, compact connective tissue that connect muscle to bone designed to transmit forces and withstand tension during muscle contraction. Here we show the ultrastructural features of tendon’s components.
Tresoldi, Ilaria; Oliva, Francesco; Benvenuto, Monica; Fantini, Massimo; Masuelli, Laura; Bei, Roberto; Modesti, Andrea
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.
Sensharma, P. K.; Kadivar, M. H.; Haftka, R. T.
Objective We have previously shown (Hunziker and Rosenberg, J Bone Joint Surg 1996;78A:721–33) that synovial cells can be induced to migrate into partial-thickness articular cartilage defects, therein to proliferate and subsequently to deposit a scar-like tissue. We now wished to ascertain whether these synovial cells could be stimulated to transform into chondrocytes, and thus to lay down cartilage tissue, by
E. B. Hunziker
Background Treatment of partial-thickness articular surface rotator cuff tears varies from simple débridement with or without an acromioplasty\\u000a to various repair techniques. These repair techniques have included in situ transtendinous methods, as well as completion\\u000a of the tear and repairing the full-thickness defect. The transtendinous techniques can be associated with stiffness and completing\\u000a the tear takes down normal intact tissue. Therefore,
Edwin E. Spencer Jr
Some treatments for full thickness defects of articular cartilage, such as cultured chondrocyte transplantation, have already been done. However, to overcome osteoarthritis, we must further study the partial thickness defect of articular cartilage. It is much more difficult to repair a partial thickness defect because few repairing cells can address such injured sites. We herein show that bioengineered layered chondrocyte
Nagatoshi Kaneshiro; Masato Sato; Miya Ishihara; Genya Mitani; Hideaki Sakai; Joji Mochida
A clinical trial was devised to determine whether the healing of partial thickness burns was retarded by the use of silver sulphadiazine cream (SSD) compared with simple, non-bacteriocidal dressings. Biopsy-confirmed partial thickness burns of at least 2% confluent area were dressed according to a strict protocol to compare the rate of epithelialisation of the control dressing, tulle gras, with that obtained with the use of silver sulphadiazine. The same comparative dressing regimen was carried out on a series of split thickness graft donor sites. Twenty such donor sites and fifteen burn areas were admitted to the trial. The mean time to healing of SSD-treated burn areas was longer than that for tulle gras; the difference when analysed by paired t-test was statistically significant (p less than 0.05). There was very little difference in the compared healing rates of the donor sites, which implies that SSD does not retard epithelialisation of dermal depth injuries but rather that the delayed healing is a unique response of the partial thickness burn wound to the presence of SSD. A review of the relevant literature is included in the discussion. PMID:2679953
Stern, H S
Aquacel Hydrofiber is a moisture retentive topical dressing that has been demonstrated to be safe and efficacious for the management of partial-thickness burns, showing parity for most dressing related aspects to cadaver skin for this indication. Recently, 1.2% w/w silver has been added to the Aquacel Hydrofiber, to create Aquacel Ag. This new material releases silver within the dressing for up to two weeks, and it is this duration that differentiates it from other sustained release silver delivery products indicated for burn management. The dressing was tested in a phase II noncomparative trial in superficial, mid dermal, and mixed partial-thickness burns. Percentage and speed of reepithelialization were satisfactory and appear to be similar at least to results noted with silver sulfadiazine, although, no direct comparisons were performed in this study. Pain reduction between baseline and postburn day number three and five was statistically significant. Conformability, general ease of use and other functional dressing properties were rated very positively. Overall, Aquacel Ag combines several properties known to be beneficial for the management of partial-thickness burns and is a very good choice for superficial and mid-thickness burn injuries. PMID:14726745
Caruso, Daniel M; Foster, Kevin N; Hermans, Michel H E; Rick, Christina
BackgroundIn massive rotator cuff tears a teres major (TMj) tendon transfer to the insertion of the supraspinatus (SSp) reverses its adduction moment arm into abduction which is supposed to be an adequate salvage procedure. Analysis of muscle function to find biomechanical ground of such success is scarce.
Frans Steenbrink; Rob G. H. H. Nelissen; Carel G. M. Meskers; Michiel A. J. van de Sande; Piet M. Rozing; Jurriaan H. de Groot
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.
Beason, David P.; Tucker, Jennica J.; Lee, Chang Soo; Edelstein, Lena; Abboud, Joseph A.; Soslowsky, Louis J.
Seventy-eight pediatric burn patients treated by enzymatic debridement with collagenase clostridiopeptidase A (CCA), were compared to 41 patients those burn wounds were excised surgically. Patients whose burn wounds were initially assessed as partial-thickness at admission were enrolled in the study. Total removal of eschar was achieved in 49 of 78 (62.8%) patients by CCA only (group D). In 29 patients (37.2%), therapy with CCA was ceased because of the development of burn wound infection or a manifest need for grafting of the wound, therefore, these patients underwent tangential wound excision (group DS). The records of 41 patients, treated by early tangential excision, having similar burn wounds by extent and depth with groups D and DS were used as controls (group S). There was no significant difference between the time to achieve a clean wound bed in groups D, DS and S (mean 7.8, 8, and 7 days, respectively, P>0.05). In group D, none of the patients required blood transfusion, except one. Patients in group DS were found to have fewer excisions (mean 1.1) when compared to those in group S (mean 1.5, P<0.05). The shortest hospital stay was found in group D (12.5 days, P<0.01). In conclusion, the use of CCA, provided a short hospital stay, reduced the overall need for surgery and blood transfusions in patients with partial-thickness burns. Thus, CCA should be considered as an initial treatment of choice for removal of eschar in children, having a partial-thickness burn wound without infection. PMID:12464480
Ozcan, Co?kun; Ergün, Orkan; Celik, Ahmet; Cördük, Nergül; Ozok, Geylani
We determined on histologic examination the degree of degeneration at the insertion of 3 rotator cuff tendons in 76 cadaveric shoulders, 17 of which had a partial tear of the supraspinatus. Fiber thinning, the presence of granulation tissue, and incomplete tearing of fibers, all evidence of degeneration, were quantified separately for each tendon. Among the shoulders that were intact on macroscopy, no significant difference in degeneration score could be found. In all 3 tendons degeneration was more prominent on the articular sides compared with the bursal sides (P < .0001). The degeneration score of partially torn supraspinatus was significantly higher than that of the intact tendons (P < .0001). The extent of granulation tissue, 1 criterion of degeneration, seemed to contribute mostly to this difference. Intrinsic degeneration occurred foremost in the articular side of the rotator cuff and might constitute the primary cause of rotator cuff tearing. PMID:10633891
Sano, H; Ishii, H; Trudel, G; Uhthoff, H K
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
Breuing, K; Eriksson, E; Liu, P; Miller, D R
This study investigated critical physicochemical attributes of low (LV), medium (MV) and high molecular weight (HV) sodium carboxymethylcellulose (SCMC) scaffolds in partial thickness wound healing. SCMC scaffolds were prepared by solvent-evaporation technique. Their in vitro erosion, moisture affinity, morphology, tensile strength, polymer molecular weight and carboxymethyl substitution, and in vivo wound healing profiles were determined. Inferring from rat wound size, re-epithelialization and histological profiles, wound healing progressed with HV scaffold>LV-MV scaffold>control with no scaffold. The transepidermal water loss (TEWL) from wound of rats treated by control>HV scaffold>LV-MV scaffold. HV scaffold had the highest tensile strength of all matrices and was resistant to erosion in simulated wound fluid. In spite of constituting small nanopores, it afforded a substantial TEWL than MV and LV scaffolds from wound across an intact matrix through its low moisture affinity characteristics. The HV scaffold can protect moisture loss without its excessive accumulation at wound bed which hindered re-epithelialization process. Regulation of transepidermal water movement and wound healing by scaffolds was governed by SCMC molecular weight instead of its carboxymethyl substitution degree or matrix pore size distribution, with large molecular weight HV preferred over lower molecular weight samples. PMID:20974238
Ramli, Nor Amlizan; Wong, Tin Wui
Improved healing of full- and partial-thickness cutaneous wounds in wet and moist environments is due primarily to retention of biological fluids over the wound preventing desiccation of denuded dermis or deeper tissues. This also allows faster and unimpeded migration of keratinocytes over the wound surface and enables the naturally occurring cytokines and growth factors to exert their beneficial effect on
B. S. Atiyeh; C. A. Al-Amm; K. A. El-Musa; A. Sawwaf; R. Dham
Oxidized linoleic acid metabolites (OLAMs) are a class of endogenous transient receptor potential vanilloid 1 (TRPV1) channel agonists released on exposure of tissue to transient noxious temperatures. These lipid compounds also contribute to inflammatory and heat allodynia. Because 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 postburn pain injury. This peripheral model of burn injury had marked thermal allodynia peaking at 24h after thermal injury, with allodynia being maintained for up to 7d. Immunohistochemical characterization of tissue taken from injury sites revealed an increase in leukocyte/macrophage infiltration that was colocalized with TRPV1-positive fibers. Using this peripheral thermal injury model, we found that pharmacological blockade of peripheral TRPV1 receptors reduced thermal allodynia by about 98%. Moreover, there was a significant increase in OLAM levels compared to naive controls in hind paw skin biopsies. Additional studies of the metabolism of [C(14)]-linoleic acid in skin biopsies revealed the role of the cytochrome P450 (CYP) system in mediating the metabolism of linoleic acid after thermal injury. Finally, we demonstrated that direct inhibition of OLAMs using OLAM antibodies and indirect inhibition using the CYP inhibitor ketoconazole significantly reduced postburn thermal allodynia. Collectively, these findings point to a novel role of the OLAMs and CYP-related enzymes in generating postburn allodynia via activation of peripheral TRPV1. PMID:23891895
Green, Dustin P; Ruparel, Shivani; Roman, Linda; Henry, Michael A; Hargreaves, Kenneth M
Extracellular adenosine triphosphate (ATP), present in thermally injured tissue, modulates the inflammatory response and causes significant tissue damage. The authors hypothesize that neutrophil infiltration and ensuing tissue necrosis would be mitigated by removing ATP-dependent signaling at the burn site. Mice were subjected to 30% TBSA partial-thickness scald burn by dorsal skin immersion in a water bath at 60 or 20°C (nonburn controls). In the treatment arm, an ATP hydrolyzing enzyme, apyrase, was applied directly to the site immediately after injury. Skin was harvested after 24 hours and 5 days for hematoxylin and eosin stain, elastase, and Ki-67 staining. Tumor necrosis factor (TNF)-? and interferon (IFN)-? expression were measured through quantitative real-time polymerase chain reaction. At 24 hours, the amount of neutrophil infiltration was different between the burn and burn + apyrase groups (P < .001). Necrosis was less extensive in the apyrase group when compared with the burn group at 24 hours and 5 days. TNF-? and IFN-? expression at 24 hours in the apyrase group was lower than in the burn group (P < .05). However, Ki-67 signaling was not significantly different among the groups. The results of this study support the role of extracellular ATP in neutrophil activity. The authors demonstrate that ATP hydrolysis at the burn site allays the neutrophil response to thermal injury and reduces tissue necrosis. This decrease in inflammation and tissue necrosis is at least partially because of TNF-? and IFN-? signaling. Apyrase could be used as topical inflammatory regulators to quell the injury caused by inflammation. PMID:23877144
Bayliss, Jill; Delarosa, Sara; Wu, Jianfeng; Peterson, Jonathan R; Eboda, Oluwatobi N; Su, Grace L; Hemmila, Mark; Krebsbach, Paul H; Cederna, Paul S; Wang, Stewart C; Xi, Chuanwu; Levi, Benjamin
Tendon attaches to bone across a functionally graded interface, “the enthesis”. A gradient of mineral content is believed to play an important role for dissipation of stress concentrations at mature fibrocartilaginous interfaces. Surgical repair of injured tendon to bone often fails, suggesting that the enthesis does not regenerate in a healing setting. Understanding the development and the micro/nano-meter structure of this unique interface may provide novel insights for the improvement of repair strategies. This study monitored the development of transitional tissue at the murine supraspinatus tendon enthesis, which begins postnatally and is completed by postnatal day 28. The micrometer-scale distribution of mineral across the developing enthesis was studied by X-ray micro-computed tomography and Raman microprobe spectroscopy. Analyzed regions were identified and further studied by histomorphometry. The nanometer-scale distribution of mineral and collagen fibrils at the developing interface was studied using transmission electron microscopy (TEM). A zone (?20 µm) exhibiting a gradient in mineral relative to collagen was detected at the leading edge of the hard-soft tissue interface as early as postnatal day 7. Nanocharacterization by TEM suggested that this mineral gradient arose from intrinsic surface roughness on the scale of tens of nanometers at the mineralized front. Microcomputed tomography measurements indicated increases in bone mineral density with time. Raman spectroscopy measurements revealed that the mineral-to-collagen ratio on the mineralized side of the interface was constant throughout postnatal development. An increase in the carbonate concentration of the apatite mineral phase over time suggested possible matrix remodeling during postnatal development. Comparison of Raman-based observations of localized mineral content with histomorphological features indicated that development of the graded mineralized interface is linked to endochondral bone formation near the tendon insertion. These conserved and time-varying aspects of interface composition may have important implications for the growth and mechanical stability of the tendon-to-bone attachment throughout development.
Schwartz, Andrea G.; Pasteris, Jill D.; Genin, Guy M.; Daulton, Tyrone L.; Thomopoulos, Stavros
The objectives of this study were to use magnetic resonance (MR) imaging to evaluate the prevalence, size, location, and clinical relevance of tendon rerupture following complete repair of full-thickness rotator cuff tear (RCT). A total of 78 surgically proven full-thickness rotator cuff tears in 74 patients were retrospectively included in the study. Clinical assessment was performed using the University of California at Los Angeles score. Postoperative MR imaging was evaluated to determine prevalence, size, and location of tendon rerupture. At a mean 48.4 months' follow-up, 62 shoulders (79.5%) had favorable outcomes and 45 shoulders (57.6%) showed rerupture on MR imaging studies. Reruptures were significantly more prevalent among patients with intermediate-to-bad outcomes (81.3%), with surgically demonstrated two-tendon tears (78.9%) or three-tendon tears (100%), and with preoperative fatty degeneration of the supraspinatus muscle greater than 1 (91.6%). Reruptures were also significantly larger in those subgroups. Complete repair of RCT of all sizes may have favorable outcomes in a significant proportion of patients in spite of a high prevalence of reruptures. Preoperative tear size and degree of muscle fatty degeneration influence the prevalence and rerupture size. After repair of supraspinatus tears, reruptures tend to invade the posterior aspect of the tendon. PMID:16518655
Mellado, J M; Calmet, J; Olona, M; Ballabriga, J; Camins, A; Pérez del Palomar, L; Giné, J
The standard treatment of partial-thickness burns includes topical silver products such as silver sulfadiazine (SSD) cream and enclosed dressings including silver-impregnated foam (Mepilex Ag; Molnlycke Health Care, Gothenburg, Sweden) and silver-laden sheets (Aquacel Ag; ConvaTec, Skillman, NJ). The current state of health care is limited by resources, with an emphasis on evidence-based outcomes and cost-effective treatments. This study includes a decision analysis with an incremental cost-utility ratio comparing enclosed silver dressings with SSD in partial-thickness burn patients with TBSA less than 20%. A comprehensive literature review was conducted to identify clinically relevant health states in partial-thickness burn patients. These health states include successful healing, infection, and noninfected delayed healing requiring either surgery or conservative management. The probabilities of these health states were combined with Medicare CPT reimbursement codes (cost) and patient-derived utilities to fit into the decision model. Utilities were obtained using a visual analog scale during patient interviews. Expected cost and quality-adjusted life years (QALYs) were calculated using the roll-back method. The incremental cost-utility ratio for enclosed silver dressing relative to SSD was $40,167.99/QALY. One-way sensitivity analysis of complication rates confirmed robustness of the model. Assuming a maximum willingness to pay $50,000/QALY, the complication rate for SSD must be 22% or higher for enclosed silver dressing to be cost effective. By varying complication rates for SSD and enclosed silver dressings, the two-way sensitivity analysis demonstrated the cost effectiveness of using enclosed silver dressing at the majority of complication rates for both treatment modalities. Enclosed silver dressings are a cost-effective means of treating partial thickness burns. PMID:24121806
Sheckter, Clifford C; Van Vliet, Michael M; Krishnan, Naveen M; Garner, Warren L
Objective: To determine if the experimental (keratin-based) dressing accelerates epithelialization rates during healing of partial-thickness wounds, relative to a Standard Care dressing. Method: A randomized control trial was conducted using a Standard Care dressing side by side with the experimental dressing on a sample (n=26) of partial-thickness donor site wounds. The proximal/distal placement of the control and treatment was randomized. Percentage epithelialization after approximately 7 days was estimated from which time to fully epithelialize can be inferred. Patients were grouped into “young” (?50 y/o) and “old” (>50 y/o). Results: For the “old” patients (n=15), the median epithelialization percentage at 7 days is 5% and was significantly (P=.023) greater for the experimental dressing. For the “young” patients (n=11), the median epithelialization percentage at 7 days was 80% and there is no significant difference between the experimental and Standard Care control dressings. Conclusions: The experimental dressing significantly increases the rate of epithelialization of acute, traumatic partial-thickness wounds in older patients. We suggest that the dressing may be clinically useful in similar situations where epithelialization may be delayed because of patient or wound characteristics.
Davidson, Andrew; Jina, N. Hamesh; Marsh, Clive; Than, Martin; Simcock, Jeremy W.
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 Î¼m wavelength can create the partial thickness channel in the sclera in ex vivo human eyes  and aqueous outflow can be increased by these channels in porcine eyes . It was also shown that the outflow rate is reduced over time in ex vivo human eyes . Therefore, the control experiment without laser treatment at the same condition was conducted and showed that outflow was reduced by 1.5 +/- 0.8 Î¼l/min at 15mmHg and 1.8 +/- 1.0 Î¼l/min at 25mmHg. However, the outflow rate increased by 0.26 Î¼l/min at 15mmHg and 0.15 Î¼l/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.
Chai, Dongyul; Chaudhary, Gautam; Kurtz, Ron; Juhasz, Tibor
Internal snapping hip syndrome, or psoas tendonitis, is a recognised cause of nonarthritic hip pain. The majority of patients are treated conservatively; however, occasionally patients require surgical intervention. The two surgical options for iliopsoas tendinopathy are step lengthening of the iliopsoas tendon or releasing the tendon at the lesser trochanter. Although unusual, refractory snapping usually occurs soon after tenotomy. We report a case of a 47-year-old active female with internal snapping and pain following an open psoas tenotomy. Postoperatively she was symptom free for 13 years. An MRI arthrogram revealed reformation of a pseudo iliopsoas tendon reinserting into the lesser trochanter. The pain and snapping resolved after repeat iliopsoas tendon release. Reformation of tendons is an uncommon sequela of tenotomies. However the lack of long-term studies makes it difficult to calculate prevalence rates. Tendon reformation should be included in the differential diagnosis of failed tenotomy procedures after a period of symptom relief.
Garala, K.; Power, R. A.
Internal snapping hip syndrome, or psoas tendonitis, is a recognised cause of nonarthritic hip pain. The majority of patients are treated conservatively; however, occasionally patients require surgical intervention. The two surgical options for iliopsoas tendinopathy are step lengthening of the iliopsoas tendon or releasing the tendon at the lesser trochanter. Although unusual, refractory snapping usually occurs soon after tenotomy. We report a case of a 47-year-old active female with internal snapping and pain following an open psoas tenotomy. Postoperatively she was symptom free for 13 years. An MRI arthrogram revealed reformation of a pseudo iliopsoas tendon reinserting into the lesser trochanter. The pain and snapping resolved after repeat iliopsoas tendon release. Reformation of tendons is an uncommon sequela of tenotomies. However the lack of long-term studies makes it difficult to calculate prevalence rates. Tendon reformation should be included in the differential diagnosis of failed tenotomy procedures after a period of symptom relief. PMID:23662230
Garala, K; Power, R A
Silver sulfadiazine has been used as a topical burn wound treatment for many years. Pain associated with dressing changes is a common problem in burn wounds. Aquacel Ag, a hydrofiber dressing coated with ionic silver has been reported to reduce burn wound infection and promote antimicrobial activity. The purpose of this study was to show the benefits of Aquacel Ag for the treatment of partial thickness burns. This prospective randomized study was conducted in 70 patients who had partial thickness burns less than 15% of total body surface area and were treated at Siriraj outpatient burn clinic during December 2006-February 2008. Patients were divided into two groups: Aquacel Ag-treated group with dressing changes every 3 days (35 patients) and 1% silver sulfadiazine-treated group, with daily dressing changes (35 patients). There was no difference in demographic data including age, gender, burn percentage between groups. Time-to-wound healing pain score during dressing change and cost of treatment were compared between both groups. Time-to-wound closure was significantly shorter in the Aquacel Ag-treated group (10 +/- 3 versus 13.7 +/- 4 days, P < 0.02) as well as pain scores at days 1, 3 and 7 (4.1 +/- 2.1, 2.1 +/- 1.8, 0.9 +/- 1.4 versus 6.1 +/- 2.3, 5.2 +/- 2.1, 3.3 +/- 1.9, respectively, P < 0.02). Total cost of treatment was 52 +/- 29 US dollars for the Aquacel Ag-treated group versus 93 +/- 36 US dollars for the silver sulfadiazine-treated group. This study showed that Aquacel Ag increased time to healing, decreased pain symptoms and increased patient convenience because of limiting the frequency of replacement of the dressing at lower total cost. This study confirms the efficacy of Aquacel Ag for the treatment of partial thickness burns at an outpatient clinic. PMID:20528992
Muangman, Pornprom; Pundee, Chanin; Opasanon, Supaporn; Muangman, Saipin
Partial-thickness rotator cuff tears comprise a partial interruption of the continuity of the tendon, with no relation to glenohumeral joint and subacromial bursa, as opposed to complete tears or the rotator cuff, and essentially affect the supraspinatus tendon. These might be in the form of bursal side tears, articular side tears or intrasubstance tears. Partial bursal side tears are explained
Philippe Goupille; Isabelle Griffoul; Saloua Mammou; Denis Mulleman
This prospective, randomized study compared protocols of care using either AQUACEL Ag Hydrofiber (ConvaTec, a Bristol-Myers Squibb company, Skillman, NJ) dressing with silver (n = 42) or silver sulfadiazine (n = 42) for up to 21 days in the management of partial-thickness burns covering 5% to 40% body surface area (BSA). AQUACEL Ag dressing was associated with less pain and anxiety during dressing changes, less burning and stinging during wear, fewer dressing changes, less nursing time, and fewer procedural medications. Silver sulfadiazine was associated with greater flexibility and ease of movement. Adverse events, including infection, were comparable between treatment groups. The AQUACEL Ag dressing protocol tended to have lower total treatment costs (Dollars 1040 vs. Dollars 1180) and a greater rate of re-epithelialization (73.8% vs 60.0%), resulting in cost-effectiveness per burn healed of Dollars 1,409.06 for AQUACEL Ag dressing and Dollars 1,967.95 for silver sulfadiazine. A protocol of care with AQUACEL(R) Ag provided clinical and economic benefits compared with silver sulfadiazine in patients with partial-thickness burns. PMID:16679897
Caruso, Daniel M; Foster, Kevin N; Blome-Eberwein, Sigri A; Twomey, John A; Herndon, David N; Luterman, Arnold; Silverstein, Paul; Antimarino, Jeffrey R; Bauer, Gregory J
ObjectiveTo investigate cartilage response to fibroblast growth factor-2 (FGF-2) with increasing age in vivo, we examined the effect of FGF-2 on partial thickness defects of immature and mature rabbits.
Tetsuya Yamamoto; Shigeyuki Wakitani; Kazuhiko Imoto; Takako Hattori; Hiroyuki Nakaya; Masanobu Saito; Kazuo Yonenobu
Background: Partial-thickness defects involving the vermilion and mucosa of the lip are difficult to repair surgically. Objective: The purpose of this study was to evaluate the cosmetic and functional effectiveness of second-intention healing in the repair of partial-thickness defects confined predominantly to the vermilion and mucosa of the lip. Methods: Thirteen patients with squamous cell carcinoma of the lip underwent
Hugh M. Gloster
We describe a case of an avulsion of the scapular spine at the origin of the supraspinatus muscle, with successful conservative treatment. An isolated avulsion is rare, as most avulsions occur in combination with other (more severe) injuries such as fractures of the scapula body or neck, coracoid process, glenoid or humerus. These injuries are mostly seen in high-energy trauma cases and need their own specific treatment. One should therefore always rule out concurrent trauma before treating conservatively. PMID:22134393
Vochteloo, Anne J; Henket, Marjolijn; Vincken, Patrice W; Nagels, Jochem
Latissimus dorsi transfer is a well-established method for the treatment of posterosuperior massive irreparable rotator cuff tears. We propose using an arthroscopically assisted technique that avoids insult to the deltoid. With the patient in the lateral decubitus position, an L-shaped incision is made along the anterior belly of the latissimus muscle and then along the posterior axillary line. The latissimus and teres major are identified and separated. The tendon insertion of the latissimus is isolated, and a FiberWire traction suture (Arthrex, Naples, FL) is placed, facilitating dissection of the muscle to the thoracodorsal neurovascular pedicle and subsequent mobilization. The interval deep to the deltoid and superficial to the teres minor is developed into a subdeltoid tunnel for arthroscopic tendon transfer. The latissimus tendon is then transferred and stabilized arthroscopically to the lateral aspect of the infraspinatus and supraspinatus footprints by multiple suture anchors. PMID:23767006
Villacis, Diego; Merriman, Jarrad; Wong, Karlton; Rick Hatch, George F
Atrophy of both the supraspinatus and infraspinatus muscles is usually caused by chronic rotator cuff tear, but may also derive from suprascapular nerve entrapment at the spinoglenoid notch. Isolated infraspinatus muscle atrophy is uncommon, and typically associates with suprascapular nerve entrapment occurring distal to the spinoglenoid notch. However, isolated atrophy of the infraspinatus muscle due to insertional tear of the infraspinatus tendon may also occur. We present a case of a 43-year-old male with isolated infraspinatus muscle atrophy and fatty degeneration following an isolated full-thickness infraspinatus tendon tear at the insertion site on the humerus. While it is important to rule out other causes of infraspinatus muscle atrophy, such as concomitant rotator cuff tendon/muscle pathology or suprascapular nerve palsy, we present this case to increase awareness of this uncommon clinical presentation and the potential implications for treatment. PMID:21918868
Kolbe, Amy B; Collins, Mark S; Sperling, John W
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.
Many alternative therapies are used as first aid treatment for burns, despite limited evidence supporting their use. In this study, Aloe vera, saliva and a tea tree oil impregnated dressing (Burnaid) were applied as first aid to a porcine deep dermal contact burn, compared to a control of nothing. After burn creation, the treatments were applied for 20 min and the wounds observed at weekly dressing changes for 6 weeks. Results showed that the alternative treatments did significantly decrease subdermal temperature within the skin during the treatment period. However, they did not decrease the microflora or improve re-epithelialisation, scar strength, scar depth or cosmetic appearance of the scar and cannot be recommended for the first aid treatment of partial thickness burns. PMID:18603378
Cuttle, Leila; Kempf, Margit; Kravchuk, Olena; George, Narelle; Liu, Pei-Yun; Chang, Hong-En; Mill, Julie; Wang, Xue-Qing; Kimble, Roy M
Achilles tendon disorders include tendinosis, paratenonitis, insertional tendinitis, retrocalcaneal bursitis, and frank rupture. Patients present with pain and swelling in the posterior aspect of the ankle. Magnetic resonance imaging and ultrasound are helpful in confirming the diagnosis and guiding treatment. Nonsurgical management of Achilles tendon disorders includes nonsteroidal anti-inflammatory drugs, physical therapy, bracing, and footwear modification. Surgical treatment includes debridement of the diseased area of the tendon with direct repair. Tendon transfer may be necessary to augment the strength of the Achilles tendon. PMID:24559878
Weinfeld, Steven B
Two studies into the use of allograft skin in the treatment of partial thickness burn injuries in this burn centre have provided the opportunity to discuss changes and similarities over a 20 year period. The first study described results obtained with cryopreserved allografts in partial thickness burns in the period 1979-1981. The second study concerned patients with partial thickness injuries treated with glycerol-preserved allografts in the period 1998-2000. A reduction was noted concerning the need for secondary autografting in the group treated with glycerolized allografts. The probability that this difference has occurred by chance is small (P=0.089). Various other factors that might account for the differences in outcome, include general improvements in health and social welfare, differences in treatment protocols, and differences in allograft properties. A prospective comparative trial is indicated to study direct differences between the two types of allograft. PMID:12237059
Vloemans, A F P M; Middelkoop, E; Kreis, R W
\\u000a Aim: This study aims to simultaneously measure the bursal and articular strains on the supraspinatus and demonstrate the effect\\u000a of tears and repairs with an intact glenohumeral joint.\\u000a \\u000a \\u000a Methodology: Nine fresh-frozen shoulders were tested on a purpose-built rig. Weights totaling 10 kg were loaded at the rotator\\u000a cuff muscles and displacement variable reluctance transducers (DVRTs) were used to measure the
J. M. Sheng; K. S. A. Yew; S. M. Chou; S. H. Tan; D. T. T. Lie
Objectives: To evaluate the use of EZ Derm® (Molnlycke Health Care, US, LLC, Norcross, GA) on partial-thickness burns. Methods: A retrospective review of medical records from patients presenting to the Tampa General Regional Burn Center from January 1, 2008, through January 1, 2012, was conducted. A hospitalwide list of patients was generated on the basis of the presence of charge codes for EZ Derm®. All encounters that did not pass through the Burn Unit were excluded. Applicable charts were reviewed for basic patient characteristics, burn characteristics, outcomes, and complications. Complications were defined as premature separation of EZ Derm®, deviation from a flat fully epithelized wound at the time of final EZ Derm® separation and hypertrophic/keloid scaring. Results: A total of 157 patients were identified and met the study criteria. Eighteen complications were reported from 16 of the 157 patients. Complications were attributed to positioning (2/133 = 1.5%), infection (4/133 = 3.0%), incomplete epithelialization at time of separation (3/133 = 2.2%), need for additional excision and grafting (6/133 = 4.5%), hypertrophic scaring (2/60 = 3.3), and cryptogenic (1/133 = 0.75). Conclusions: EZ Derm® has proven to be a robust wound dressing that provides cost-effective, consistent durable wound coverage with minimal complications that resolve without long-term sequela.
Troy, Jared; Karlnoski, Rachel; Downes, Katheryne; Brown, Kimberly S.; Cruse, C. Wayne; Smith, David J.; Payne, Wyatt G.
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.
Summary Tendon imaging plays a critical role in evaluating tendon diseases and injuries including mechanical, degenerative, and overuse disease, inflammatory enthesitis, as well as partial and full thickness tears. Ultrasound and magnetic resonance imaging (MRI), each with unique benefits and limitations, are commonly utilized to assist in diagnosing these diseases and conditions. This review delineates important structural properties of tendon and biochemical changes occurring in tendon pathology. This review also examines commonly injured tendons including tendons of the elbow, tendons of the rotator cuff of the shoulder, hip abductor tendons, patellar tendons, and the Achilles tendon to help clinicians better recognize tendon disease. Finally, this paper introduces several emerging imaging techniques including T2 mapping, ultra-short echo time MRI, and sonoelastography as ways in which tendon imaging and evaluation may be improved.
Weinreb, Jeffrey H.; Sheth, Chirag; Apostolakos, John; McCarthy, Mary-Beth; Barden, Benjamin; Cote, Mark P.; Mazzocca, Augustus D.
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.
Hodgson, R J; O'Connor, P J; Grainger, A J
Little knowledge exists about the healing process of the tendon to bone insertion, and hence little can be done to improve tissue healing. The goal of this study is to describe the healing of the supraspinatus tendon to its bony insertion under a variety of loading conditions. Tendons were surgically detached and repaired in rats. Rat shoulders were then immobilized, allowed cage activity, or exercised. Shoulders that were immobilized demonstrated superior structural (significantly higher collagen orientation), compositional (expression of extracellular matrix genes similar to the uninjured insertion), and quasilinear viscoelastic properties (A = 0.30 +/- 0.10 MPa vs. 0.16 +/- 0.08 MPa, B = 17.4 +/- 2.9 vs. 15.1 +/- 0.9, and tau 2 = 344 +/- 161 s vs. 233 +/- 40 s) compared to those that were exercised, contrary to expectations. With this knowledge of the healing response, treatment modalities for rotator cuff tears can be developed. PMID:12661203
Thomopoulos, S; Williams, G R; Soslowsky, L J
A number of in vivo and ex vivo skin models have been applied to human wound healing studies. A reliable skin model, which recapitulates the features of human wound repair, is essential for the clinical and mechanical investigation of human cutaneous wound healing. Full-skin ex vivo culture systems have been used in wound healing studies. However, important structures of the skin, such as the differentiation of keratinocytes and epidermis-dermis junction, are poorly characterized in this model. This study aims to develop an optimized partial-thickness human ex vivo skin culture (HESC) model to maintain human skin characteristics in vitro. During our culture, the basal layer, suprabasal layer, and stratum granulosum layer of epidermis were preserved until day 8. Analyses of hemidesmosome proteins, bullous pemphigoid antigen 1 (BP180) and 2 (BP230), showed that the integrity of the basement membrane of the epidermis was well preserved in the HESC model. In contrast, an organotypic culture with human keratinocytes and fibroblasts failed to show an integrated basement membrane. Maintenance of skin structure by histological analysis and proliferation of epidermal keratinocytes by Ki67 staining were observed in our model for 12 days. Complete re-epithelialization of the wounding area was observed at day 6 post wounding when a superficial incisional wound was created. The expression of Ki-67 and keratin 6, indicators of activated keratinocytes in epidermis, was significantly upregulated and new collagen synthesis was found in the dermis during the wound healing process. As control, we also used organotypic culture in studying the differentiation of the keratinocyte layers and incisional wound repair. It turned out that our model has advantage in these study fields. The results suggest that our HESC model retains important elements of in vivo skin and has significant advantages for the wound healing studies in vitro. PMID:22231737
Xu, Wei; Jong Hong, Seok; Jia, Shengxian; Zhao, Yanan; Galiano, Robert D; Mustoe, Thomas A
We conducted this Institutional Review Board-approved retrospective study to compare Aquacel Ag Hydrofiber dressing (Aquacel Ag) to a standard dressing for the treatment of partial thickness burns in children. We used the St. Christopher's Hospital burn center registry to identify 20 pediatric patients who had sustained partial thickness burns over a 10-month period. Ten of these patients had been treated with Aquacel Ag Hydrofiber dressing and 10 were treated with conventional Xeroflo gauze with Bacitracin Zinc ointment, the institutional standard of care for nonoperative partial-thickness burn wounds. Inclusion criteria included anyone with partial-thickness burns below the age of 18 years and in excellent baseline health. Exclusion criteria included inhalation injury, presence of full-thickness burns necessitating surgical debridement, cellulitic, or infected wounds, and percentage total body surface area involvement greater than 40%. Outcomes measured for the Aquacel Ag versus the Xeroflo gauze with Bacitracin Zinc ointment group included hospital length of stay (2.4 vs. 9.6 days), total number of in-house dressing changes (2.7 vs. 17.1), pain on a 10-point scale associated with dressing changes (6.4 vs. 8.2), total number of intravenous narcotic administrations (2.3 vs. 14.4), nursing time adjusted for percentage total body surface area (1.9 vs. 3.5 min), time to wound reepithelialization (10.3 vs. 16.3 days), and patient primary caregiver satisfaction score using a 4-point scale--with four delineating maximum satisfaction (3.8 vs. 1.8). Aquacel Ag proved to be a safe and effective means of treating partial thickness burns with a significant reduction in nursing time and patient pain involved with dressing changes. PMID:19349897
Saba, Salim Charles; Tsai, Roger; Glat, Paul
Flexible forefoot deformities, such as hallux varus, clawed hallux, hammer toes, and angular lesser toe deformities, can be treated effectively with tendon transfers. Based on the presentation of the flexible forefoot deformities, tendon transfers can be used as the primary treatment or as adjuncts to bony procedures when there are components of fixed deformities. PMID:24548515
Veljkovic, Andrea; Lansang, Edward; Lau, Johnny
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.
Tendon injuries are the second most common injuries of the hand and therefore an important topic in trauma and orthopedic patients. Most injuries are open injuries to the flexor or extensor tendons, but less frequent injuries, e.g., damage to the functional system tendon sheath and pulley or dull avulsions, also need to be considered. After clinical examination, ultrasound and magnetic resonance imaging have proved to be important diagnostic tools. Tendon injuries mostly require surgical repair, dull avulsions of the distal phalanges extensor tendon can receive conservative therapy. Injuries of the flexor tendon sheath or single pulley injuries are treated conservatively and multiple pulley injuries receive surgical repair. In the postoperative course of flexor tendon injuries, the principle of early passive movement is important to trigger an “intrinsic” tendon healing to guarantee a good outcome. Many substances were evaluated to see if they improved tendon healing; however, little evidence was found. Nevertheless, hyaluronic acid may improve intrinsic tendon healing.
Schoffl, Volker; Heid, Andreas; Kupper, Thomas
Both magnetic resonance imaging (MRI) and sonography are well suited to tendon imaging. A normal tendon on MRI demonstrates low signal intensity and on sonography, an echogenic fibrillar pattern. MRI is considered the imaging gold standard, providing an anatomic overview and excellent soft tissue contrast. Sonography is a more rapidly performed examination; it has greater resolution than that of MRI; it allows dynamic evaluation of tendons and muscles; and it can guide percutaneous therapeutic procedures. Moreover, the advent of sonographic extended-field-of-view imaging allows the demonstration of the entire length of a tendon, matching MRI’s ability to display a large anatomic region. Sonography should best be considered a focused examination, concentrating on the area of pain and clinical suspicion of pathology, whereas MRI can provide a global assessment of the region of concern. Both modalities demonstrate high accuracy for abnormalities of various tendons. This article reviews normal tendon anatomy and its imaging appearance, as well as the imaging appearances of tendon degeneration and tear.
Chang, Anthony; Miller, Theodore T.
Snail extracts have been increasingly used in numerous dermatologic conditions and recent literature attributes healing, soothing and anti-aging properties to them. This study evaluates the efficacy of Helix aspersa extract in an open wound management protocol for deep partial thickness (PT) facial burns and compares it to moist exposure burn ointment(MEBO). A total of 27 adult patients with deep partial thickness facial burns (group A) were treated by application of a snail extract cream twice daily for a maximum period of 14 days or until full epithelialization. Times until debridement and epithelialization of the burn surface were compared with those of 16 patients (group B, control) treated by MEBO. Pain scores were recorded using a visual analogue scale (VAS) on the fourth post-burn day before and 30 min after application. Mean times for eschar detachment were 9 +/- 2 days (group A) and 11 +/- 2 days (group B) (p = 0.003) and for burn surface epithelialization were 11 +/- 2 days and 15 +/- 3 days respectively (p < 0.001). VAS pain scores after application in group A were significantly lower compared to group B (p < 0.001). Helix aspersa extract is a natural, safe and effective alternative treatment in open wound management of partial thickness burns in adults. PMID:19058081
Tsoutsos, Dimosthenis; Kakagia, Despoina; Tamparopoulos, Konstantinos
The authors report a rupture of the distal tendon of biceps brachii in a 42-year-old athlete. Magnetic resonance imaging confirmed the injury. Early surgical repair was performed by reinsertion of the tendon on the radial tuberosity according to modified Boyd-Anderson technique. Indomethacin was administered prophylactically. No complications were noted. At the latest follow-up, the patient had full elbow range of
Olga D. Savvidou; Panayiotis J. Papagelopoulos; Andreas F. Mavrogenis; Antonios A. Partsinevelos; Evangelos J. Karadimas; Demetrios S. Korres
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
Fung, David T; Wang, Vincent M; Laudier, Damien M; Shine, Jean H; Basta-Pljakic, Jelena; Jepsen, Karl J; Schaffler, Mitchell B; Flatow, Evan L
Biceps tendon pathology is a common clinical problem often seen in conjunction with rotator cuff tears. A previous study found detrimental changes to biceps tendons in the presence of rotator cuff tears in a rat model. Therefore, the objective of this study was to utilize this model along with models of altered loading to investigate the effect of altered loading on the initiation of these detrimental changes. We created supraspinatus and infraspinatus rotator cuff tears in the rat and followed these tears with either increased or decreased loading. Mechanical properties were determined along the length of the biceps tendon 4 and 8 weeks following injury. At the insertion site, stiffness increased with decreased loading, while detrimental changes were seen with increased loading 4 weeks following detachments. Increased loading resulted in decreased mechanical properties along the entire tendon length at both time points. Decreased loading resulted in both increased and decreased tendon properties at different regions of the tendon at 4 weeks, but by 8 weeks, there were no differences between decreased loading and detachment alone. We could not conclude where changes begin in the tendon with altered loading, but did demonstrate that regional differences exist. These results support that there is an effect of altered loading, as decreased loading resulted in variable changes at 4 weeks that were no different from detachment alone by 8 weeks, and increased loading resulted in detrimental properties along the entire length at both 4 and 8 weeks. PMID:20719313
Peltz, Cathryn D; Hsu, Jason E; Zgonis, Miltiadis H; Trasolini, Nicholas A; Glaser, David L; Soslowsky, Louis J
The treatment of acute of Achilles tendon rupture experienced a dynamic development in the last ten years. Decisive for this development was the application of MRI and above all the ultrasonography in the diagnostics of the pathological changes and injuries of tendons. The question of rupture morphology as well as different courses of healing could be now evaluated objectively. These advances led consequently to new modalities in treatment concepts and rehabilitation protocols. The decisive input for improvements of the outcome results and particularly the shortening of the rehabilitation period came with introduction of the early functional treatment in contrast to immobilizing plaster treatment. In a prospective randomized study (1987-1989) at the Trauma Dept. of the Hannover Medical School could show no statistical differences comparing functional non-operative with functional operative therapy with a special therapy boot (Variostabil/Adidas). The crucial criteria for therapy selection results from the sonographically measured position of the tendon stumps in plantar flexion (20 degrees). With complete adaptation of the tendons' ends surgical treatment does not achieve better results than non-operative functional treatment in term of tendon healing and functional outcome. Regarding the current therapeutic standards each method has is advantages and disadvantages. Both, the operative and non-operative functional treatment enable a stable tendon healing with a low risk of re-rupture (1-2%). Meanwhile there is consensus for early functional after-treatment of the operated Achilles' tendons. There seems to be a trend towards non-operative functional treatment in cases of adequate sonographical findings, or to minimal invasive surgical techniques. PMID:10798233
Thermann, H; Hüfner, T; Tscherne, H
Herein we describe a previously seldom recognized variety of snapping hip, which is caused by snapping of the iliopsoas tendon over the iliopectineal eminence when the femur is moved from the flexed position at the hip and extended through 45 degrees of flexion. The finding is demonstrated with the patient supine and gently resisting gravity with the iliopsoas muscle, thus placing it under tension. At approximately 45 degrees of flexion, the iliopsoas tendon in two patients was confirmed radiographically to snap abruptly, coincident with an audible sound over the iliopectineal eminence of the pelvis. We believe that this occurs relatively frequently and is generally asymptomatic. PMID:6727425
Lyons, J C; Peterson, L F
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.
Allam, A.M.; Mostafa, W.; Zayed, E.; El-Gamaly, J.
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
Allam, A M; Mostafa, W; Zayed, E; El-Gamaly, J
Moist Exposed Burn Ointment (MEBO(®)) is widely used topical agent applied on skin burn. This study investigated the effect of MEBO topical application on activation and proliferation of epidermal stem cells through the immunohistochemical localization of cytokeratin 19 (CK19) as a known marker expressed in epidermal stem cells. Biopsies from normal skin and burn wounds were taken from 21 patients with partial thickness burn 1, 4, 7, 14, 21, and 28 days after treatment with MEBO. Tissue sections were prepared for histological study and for CK19 immunohistochemical localization. In control skin, only few cells showed a positive CK19 immune-reaction. Burned skin showed necrosis of full thickness epidermis that extended to dermis. Gradual regeneration of skin accompanied with an enhancement in CK19 immune-reactivity was noted 4, 7, 14 and 21 days after treatment with MEBO. On day 28, a complete regeneration of skin was observed with a return of CK19 immune-reactivity to the basal pattern again. In conclusion, the enhancement of epidermal stem cell marker CK19 after treatment of partial thickness burn injuries with MEBO suggested the role of MEBO in promoting epidermal stem cell activation and proliferation during burn wound healing. PMID:24576560
El-Hadidy, M R; El-Hadidy, A R; Bhaa, A; Asker, S A; Mazroa, S A
Conventional management of partial-thickness burn wounds includes the use of paraffin gauze dressing, frequently with topical silver-based antibacterial creams. Some creams form an overlying slough that renders wound assessment difficult and are painful upon application. An alternative to conventional management, moist exposed burn ointment (MEBO), has been proposed as a topical agent that may accelerate wound healing and have antibacterial and analgesic properties. One hundred fifteen patients with partial-thickness burns were randomly assigned to conventional (n = 58) or MEBO treatment (n = 57). A verbal numerical rating score of pain was made in the morning, after burn dressing, and some 8 hours later. Patient pain profiles were summarized by locally weighted regression smoothing technique curves and the difference between treatments estimated using multilevel regression techniques. Mean verbal numerical rating scale pain levels (cm) in week 1 for all patients were highest at 3.2 for the after dressing assessment, lowest in the evening at 2.6, and intermediate in the morning at 3.0. This pattern continued at similar levels in week 2 and then declined by a mean of 0.5 in all groups in week 3. There was little evidence to suggest a difference in pain levels by treatment group with the exception of the postdressing pain levels in the first week when those receiving MEBO had a mean level of 0.7 cm (95% confidence interval, 0.2 to 1.1) lower than those on conventional therapy. MEBO appeared to bring greater pain relief for the postdressing assessment during the first week after burns. This initial relief, together with comparable pain levels experienced on other occasions, indicates that MEBO could be an alternative to conventional burns management. PMID:14501397
Ang, Erik; Lee, S-T; Gan, Christine S-G; Chan, Y-H; Cheung, Y-B; Machin, D
The mechanical effect of a partial thickness tear or laceration of a tendon is analytically modeled under various assumptions and results are compared with previous experimental data from porcine flexor tendons. Among several fibril-level models considered, a shear-lag model that incorporates fibril-matrix interaction and a fibril-fibril interaction defined by the contact area of the interposed matrix best matched published data for tendons with shallow cuts (less than 50% of the cross-sectional area). Application of this model to the case of many disrupted fibrils is based on linear superposition and is most successful when more fibrils are incorporated into the model. An equally distributed load sharing model for the fraction of remaining intact fibrils was inadequate in that it overestimates the strength for a cut less than half of the tendon's cross-sectional area. In a broader sense, results imply that shear-lag contributes significantly to the general mechanical behavior of tendons when axial loads are nonuniformly distributed over a cross section, although the predominant hierarchical level and microstructural mediators for this behavior require further inquiry. PMID:24845861
Pensalfini, Marco; Duenwald-Kuehl, Sarah; Kondratko-Mittnacht, Jaclyn; Lakes, Roderic; Vanderby, Ray
Objective To investigate the interobserver reproducibility and diagnostic feasibility of a visual grading system for assessing atrophy of the supraspinatus muscle on magnetic resonance imaging (MRI). Materials and Methods Three independent radiologists retrospectively evaluated the occupying ratio of the supraspinatus muscle in the supraspinatus fossa on 192 shoulder MRI examinations in 188 patients using a 3-point visual grading system (1, ? 60%; 2, 30-59%; 3, < 30%) on oblique sagittal T1-weighted images. The inter-reader agreement and the agreement with the reference standard (3-point grades according to absolute occupying ratio values quantitatively measured by directly contouring the muscles on MRI) were analyzed using weighted kappa. The visual grading was applied by a single reader to a group of 100 consecutive patients who had undergone rotator cuff repair to retrospectively determine the association between the visual grades at preoperative state and postsurgical occurrences of retear. Results The inter-reader weighted kappa value for the visual grading was 0.74 when averaged across three reader pairs (0.70-0.77 for individual reader pairs). The weighted kappa value between the visual grading and the reference standard ranged from 0.75 to 0.83. There was a significant difference in retear rates of the rotator cuff between the 3 visual grades of supraspinatus muscle atrophy on MRI in univariable analysis (p < 0.001), but not in multivariable analysis (p = 0.026). Conclusion The 3-point visual grading system may be a feasible method to assess the severity of supraspinatus muscle atrophy on MRI and assist in the clinical management of patients with rotator cuff tear.
Lim, Hyun Kyong; Yoo, Hye Jin; Choi, Ja-Young; Kim, Sae Hoon; Choi, Jung-Ah; Kang, Heung Sik
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.
Longo, Umile Giuseppe; Lamberti, Alfredo; Petrillo, Stefano; Maffulli, Nicola; Denaro, Vincenzo
Isolated avulsion of the vastus lateralis tendon is a very rare injury. To our knowledge, only 1 case has been reported in the literature. This tendon is crucial to knee stability and proper patellofemoral tracking. As isolated avulsion of the tendon tends to occur in young, active males, early surgical repair is recommended to allow them to maintain a high level of functional ability. We present the case of a 49-year-old man who sustained an isolated vastus lateralis tendon avulsion injury. The injury was successfully treated with suture anchor repair. PMID:24278905
Frank, Jonathan M; Riedel, Matthew D; McCormick, Frank M; Nho, Shane J
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
Theobald, Peter S; Dowson, Duncan; Khan, Ilyas M; Jones, Michael D
During routine dissection of an adult human cadaver, a suite of tendinous anomalies was discovered in the left hallucal region. Whereas the main tendon of the extensor hallucis longus muscle inserted normally, two accessory tendons were found coursing medial and lateral to the main tendon. The most lateral tendon originated from a supernumerary muscle belly and merged with the tendon of extensor hallucis brevis to form a composite tendon. The most medial tendon crossed the metatarsophalangeal joint and joined the composite tendon deep to the tendon of extensor hallucis longus. A terminal tendon, consisting of these three contributions, inserted upon the proximal hallucal phalanx. This variant likely arose due to atypical differentiation of the common extensor muscle mass during development, and is of particular significance to clinicians performing arthroscopy, tendon transfers, and other surgical procedures. PMID:19159364
Hill, Robert V; Gerges, Luke
Rotator cuff tears are a common clinical problem that can result in pain and disability. Previous studies in a rat model showed enhanced tendon to bone healing with postoperative immobilization. The objective of this study was to determine the effect of postimmobilization activity level on insertion site properties and joint mechanics in a rat model. Our hypothesis was that exercise following a short period of immobilization will cause detrimental changes in insertion site properties compared to cage activity following the same period of immobilization, but that passive shoulder mechanics will not be affected. We detached and repaired the supraspinatus tendon of 22 Sprague-Dawley rats, and the injured shoulder was immobilized postoperatively for 2 weeks. Following immobilization, rats were prescribed cage activity or exercise for 12 weeks. Passive shoulder mechanics were determined, and following euthanasia, tendon cross-sectional area and mechanical properties were measured. Exercise following immobilization resulted in significant decreases compared to cage activity in range of motion, tendon stiffness, modulus, percent relaxation, and several parameters from both a structurally based elastic model and a quasi-linear viscoelastic model. Therefore, we conclude that after a short period of immobilization, increased activity is detrimental to both tendon mechanical properties and shoulder joint mechanics, presumably due to increased scar production. PMID:20058271
Peltz, Cathryn D; Sarver, Joseph J; Dourte, Leann M; Würgler-Hauri, Carola C; Williams, Gerald R; Soslowsky, Louis J
The Achilles tendon is susceptible to various types of acute and chronic injuries as a consequence of its large size, enormous continuous functional demands during gait, and poor blood supply. Also, the occurrence of overuse syndromes of the Achilles tendon is increasing due to the modern physical life style. In this article the different forms of tendinitis (insertional and non-insertional),
Aleksander Lesic; Marko Bumbasirevic
The official consumer website of: Visit ACFAS.org | About ACFAS | Información en Español ... tendon serves as one of the major supporting structures of the foot, helping it to function while walking. Posterior tibial tendon dysfunction (PTTD) is a condition caused ...
A potential treatment for chronic tendinosis or tendinopathy is percutaneous ultrasound-guided tendon fenestration, also termed dry needling or tenotomy. This procedure involves gently passing a needle through the abnormal tendon multiple times to change a chronic degenerative process into an acute condition that is more likely to heal. This article reviews the literature on tendon fenestration and describes the technical aspects of this procedure including postprocedural considerations. Although peer-reviewed literature on this topic is limited, studies to date have shown that ultrasound-guided tendon fenestration can improve patient symptoms. Several other percutaneous treatments for tendinopathy that include prolotherapy, autologous whole-blood injection, and autologous platelet-rich plasma injection are often performed in conjunction with fenestration. It is currently unknown if these other percutaneous procedures have any benefit over ultrasound-guided tendon fenestration alone. PMID:23487340
Chiavaras, Mary M; Jacobson, Jon A
Background The superiority of tenotomy vs. tenodesis for surgery on lesions of the long head of the biceps brachii tendon is still under debate. Indeed, high-quality evidence is lacking, mainly because of methodological problems, such as retrospective design, population sample size or lack of patient randomization. Methods/Design The study will be a two-center, double-blind, randomized, controlled trial to compare patients treated with biceps tenotomy or tenodesis for lesions of the long head of the biceps brachii tendon over a 2-year follow-up period. The study participants will be 128 adults with biceps brachii tendinopathy and supraspinatus tendon tears. The primary end point will be the postoperative difference in the Constant-Murley score (CMS) between the 2 groups at the two-year follow-up. A comparison of the mean improvement with standard age- and gender-related CMS will be performed. The secondary end point will be evaluation of the postoperative general health of patients, as evaluated with Short Form 36 (SF-36) scores. The number and severity of complications associated with use of the different surgical techniques will be assessed. Discussion This study will be the first randomized and appropriately powered clinical trial to directly compare tenotomy and biceps tenodesis. The results of this study will help to establish clinical practice guidelines for patients suffering from lesions of the long head of the biceps brachii tendon, providing important information to patients and health care providers about the possible complications, outcome predictors and effectiveness of the targeted interventions. Trial Registration Current Controlled Trials ISRCTN38839558
We previously developed chitosan cryogels from chitosan-gluconic acid conjugate without using toxic additives for wound care. In this study, we improved physiological characteristics of the previous cryogels by incorporating poly(vinyl alcohol) that also form cryogels. Mechanical strength of the cryogels was more than two times higher than that of the previous cryogels. Furthermore, the incorporation of poly(vinyl alcohol) enhanced water retention and resistance to degradation of the gels by lysozyme. The cryogels retained the favorable biological properties of the previous cryogels that they accelerate infiltration of inflammatory cells into wound sites. Time period for repairing 50 % of initial area of partial-thickness skin wound treated with the cryogels (4.0 ± 1.1 days) was shorter than those with gauze (6.5 ± 0.3 days) or a commercial hydrogel dressing (5.7 ± 0.3 days). Finally, we confirmed that incorporation of basic fibroblast growth factor into the cryogels was effective to further accelerate wound healing (2.7 ± 1.0 days). These results demonstrate that the cryogels in this study are promising for wound care. PMID:23801501
Takei, Takayuki; Nakahara, Hideki; Tanaka, Sadao; Nishimata, Hiroto; Yoshida, Masahiro; Kawakami, Koei
This paper presents an analysis of the results of repair of 102 complete flexor tendon disruptions in zone 1 which were rehabilitated by an early active mobilization technique during a 7 year period from 1992 to 1998. These injuries were subdivided into: distal tendon divisions requiring reinsertion; more proximal tendon divisions but still distal to the A4 pulley; tendon divisions
N. S. MOIEMEN; D. ELLIOT
During routine dissection of an adult human cadaver, a suite of tendinous anomalies was discovered in the left hallucal region.\\u000a Whereas the main tendon of the extensor hallucis longus muscle inserted normally, two accessory tendons were found coursing\\u000a medial and lateral to the main tendon. The most lateral tendon originated from a supernumerary muscle belly and merged with\\u000a the tendon
Robert V. Hill; Luke Gerges
Introduction: Conventional management of partial thickness facial burn wounds includes the use of silver sulphadiazine dressing s. Silver sulphadiazine forms an overlying slough that makes wound healing assessment difficult. Moist exposed burn ointment (MEBO) has b een proposed as the ideal burn wound dressing both for burns of the face and other sites. Proponents of MEBO claim that it accelera
E S W Ang; S T Lee; C S G Gan; L H Ng; D Machin
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.
Crow, Scott A.; Quach, Tony; McAllister, David R.
Extensor hallucis longus tendon injuries are uncommon, representing < 2% of tendon injuries. Lacerations are more common than spontaneous ruptures, and if neglected are often difficult to primarily repair because of tendon retraction and scarring. Few reports address the operative treatment of chronic extensor hallucis longus tendon injuries. To our knowledge the use of a gracilis tendon autograft has not been reported. We describe the use of this free tendon autograft with a hallux interphalangeal joint arthrodesis in one patient. PMID:19225994
Smith, Bertil; Coughlin, Michael
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
Gupta, Asheesh; Dai, Tianhong; Hamblin, Michael R
A discussion is presented on the practical use of preserved fascia and tendon homografts. Clinical observations on 58 patients treated at the clinic of traumatology and orthopedics at the Military Medical Academy are reviewed.
I. L. Krupko S. S. Tkachenko
Rotator cuff tendon tears are one of the most common shoulder injuries. Although surgical repair is typically beneficial, re-tearing of the tendons frequently occurs. It is generally accepted that healing is worse for chronic tears than acute tears, but the reasons for this are unknown. One potential cause may be the large tensions that are sometimes required to repair chronically torn tendons back to bone (i.e., repair tension). Therefore, the objective of this study was to utilize an animal model of chronic rotator cuff repairs to investigate the role of increased repair tension on tendon to bone healing. We hypothesized that an increase in repair tension would be related to detrimental changes to the healing insertion site. To test this hypothesis, the supraspinatus tendon of rats was surgically detached and then repaired immediately or after a delay of 2, 4, or 16 weeks. The repair tension was measured using a tensiometer and the mechanical properties, collagen organization, and protein expression of the healing insertion site were evaluated 4 and/or 16 weeks following repair. We found that the repair tension increased with time following detachment, and was related to a decrease in the failure properties and viscoelastic peak stress and an increase in cross-sectional area and stiffness of the insertion site. Therefore, repair tension should be minimized in the clinical setting. Future studies will include additional animal model studies involving the relationship between tension and muscle properties and a clinical study investigating the role of repair tension on repair failure. PMID:16600252
Gimbel, Jonathan A; Van Kleunen, Jonathan P; Lake, Spencer P; Williams, Gerald R; Soslowsky, Louis J
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 mobilisation pre and post surgery.
Griffin, M; Hindocha, S; Jordan, D; Saleh, M; Khan, W
Membranous dressings for the treatment of partial and mixed thickness burns are among the most innovative and promising new developments of the last years. In this study, we present data of a randomised prospective comparative study on a carboxymethylcellulose based dressing, Hydrofibre((R)) and glycerolized human allograft skin. In a 2 year period, 80 patients (40 for each material) were enrolled in the trial. Study wounds (<10% TBSA) that had not re-epithelialised after 14+/-3 days were debrided and grafted or, if small enough, managed with a topical antimicrobial agent. Mean total TBSA was 8.3+/-5.2%, study burn 3.7+/-2.0% for the Hydrofibre((R)) group and 7.3+/-4.3% total, 3.4+/-2.1% study burn for the allograft skin group (n.s. Wilcoxon rank sum test). No significant differences between groups were established in number of patients with superficial/deep burns. In both groups about 2/3 of the patients healed completely with the dressings applied (24/40 versus 27/40 for Hydrofibre((R)) versus allograft skin, respectively). However, a higher incidence of post-study excision and grafting was found in the Hydrofibre((R)) group (45% versus 15% in the allograft skin group, P=0.004, Mann-Whitney). At 10 weeks follow-up no significant differences were seen in scar colour, pigmentation, pliability, height or itching (Vancouver Scar Scale). Skin elasticity, measured by the Cutometer((R)), was significantly better for the allograft group (P=0.010, Wilcoxon). These differences were no longer found at 6 months and 1 year follow-up. Incidence of hypertrophy after 6 months was higher, but not significantly, in the Hydrofibre((R)) compared to the allograft skin group (52.5% versus 30%, P=0.09, chi-square). In view of the results from our comparative study on Hydrofibre((R)) versus allograft skin, we prefer the use of allograft skin for the category of larger burns of mixed depth, usually presented to burn centres. However, for partial thickness and small burns Hydrofibre((R)) can be the first choice in treatment. PMID:14556729
Vloemans, A F P M; Soesman, A M; Suijker, M; Kreis, R W; Middelkoop, E
Background Zone 2 flexor tendon injuries still represent a challenging problem to hand surgeons despite the well developed surgical techniques and suture materials. Meticulous surgical repair with atraumatic handling of the severed tendon stumps and minimal damage to the tendon sheath are particularly important to prevent postoperative adhesions and ruptures in this area. In zone 2 flexor tendon injuries proximal to the vinculas, the cut ends of the flexor tendons retract to the palm with muscle contraction. To retrieve the severed proximal flexor tendon under tendon sheath and pulley system is very difficult without damaging these structures. Many techniques are described in the literature for the delivery of the retracted proximal tendon stump to the repair site. Methods In this report we would like to present a simple and relatively atraumatic technique that facilitates passing of the retracted flexor tendon through the pulleys in zone 2. We sutured the proximal tendon stump at the distal palmar crease with 3–0 polypropylene suture and used a 14 gauge plastic feeding tube, acting like a conduit for the passage of straightened needle to the finger. Results We have used this technique 21 times without any complication in our clinic. We have not seen any suture breakage during the passage or needle breakage due to the bending of the needle. Conclusions We have found this technique is very simple and very effective in retrieving the retracted tendon stump without causing undue damage to the tendon stump or tendon sheath.
This is a study on the histologic pattern and mechanical properties of tissue-engineered tendon implanted for treatment of tendon defects. Tendons were resected from Roman chickens. Tendon cells were isolated from the tendons and cultured in vitro. The 2nd-4th passages of tendon cells were seeded on the degradable polyglycolic acid mesh to form cell-scaffold composites, which were further cultured for 7-10 days to construct tissue-engineered tendons. The tendon defects, 0.5 cm-0.8 cm in length, were made in the second digit flexor tendon bilaterally in 20 Roman chickens and then bridged with the constructed tissue-engineered tendons. At 2 weeks, 4 weeks, 6 weeks, and 8 weeks post-operation, the samples of regenerated tendons were collected for gross examination, histologic staining and biomechanical test. After implantation of the tissue-engineered tendons, the wounds healed well. The gross appearance, the cells and collagen fibers arrangement of the regenerated tendons were similar to those of natural tendons, but there were relatively not many closely packed collagen fiber bundles organized in parallel with the tendons ("remodel"), so the maximum tensile force increased slowly and its value was 15.40+/-10.63 N at 8 weeks after surgery, reaching only 23% of that of natural tendon. The maximum strain was 22.49%+/-10.21% at 8 weeks, being 10% higher than that of natural tendons. Polyglycolic acid scaffolds are degraded in vivo so rapidly that the regenerated tendons lose the normal biomechanical stimulus and then are unable to be remodeled. As a result, the mechanical strength of regenerated tendons is much lower than that of natural tendons. These results suggest that the normal biomechanical stimulus may be an important factor for the regenerated tendons to remodel. PMID:15357423
Qin, Tingwu; Zhang, Shujiang; Yang, Zhiming; Li, Xiuqun
Tears of the subscapularis are much less common than tears of the supraspinatus and infraspinatus. Subscapularislesions are usually traumatic in etiology and occur in younger patients. These lesions can be complete or limited to the superior insertion of the subscapularis, and they may be isolated or occur with other rotator cuff lesions. In most instances, treatment of subscapularis tears is
T. Bradley Edwards; Gilles Walch
Adhesion of the tendon, which can occur during healing of tendon repair, is negatively affected by the outcome of surgery. In this experimental study, we sought to prevent adhesion of the tendon, and determined the mechanical stiffness of repair tissue by wrapping sodium hyaluronate and carboxymethylcellulose (Seprafilm; Genzyme, Cambridge, Massachusetts) around the repaired tendon segments. The study group comprised 2 groups of 20 chickens. In group I, the right gastrocnemius tendons of the chickens were cut smoothly, and after tendon and sheath repair, the skin was sutured. In group II, the right gastrocnemius tendons of the chickens were cut, the tendons were repaired, and before skin closure, Seprafilm was wrapped around the repaired tendon segments. Plastic splints were used for holding the chickens' ankles in a neutral position, and they were allowed weight bearing for 8 weeks. In group II, anatomic space between the tendon-sheath and tendon was clear and the tendon-sheath complex was sliding easily around the repaired tendon segment, and this complex was more functional both biomechanically and histologically. Also, the Seprafilm-applied tendons (group II) were observed to be biomechanically more resistant to the tensile forces in group I. Seprafilm is an easily applied interpositional material that can be used safely to prevent adhesion during the tendon healing process. PMID:20349872
Yilmaz, Erhan; Avci, Mustafa; Bulut, Mehmet; Kelestimur, Halidun; Karakurt, Lokman; Ozercan, Ibrahim
Summary PRP is widely used to treat tendon and other tissue injuries in orthopaedics and sports medicine; however, the efficacy of PRP treatment on injured tendons is highly controversial. In this commentary, I reason that there are many PRP- and patient-related factors that influence the outcomes of PRP treatment on injured tendons. Therefore, more basic science studies are needed to understand the mechanism of PRP on injured tendons. Finally, I suggest that better understanding of the PRP action mechanism will lead to better use of PRP for the effective treatment of tendon injuries in clinics.
Wang, James H-C.
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.
Halpern, Alan A.; Horowitz, Bruce G.; Nagel, Donald A.
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.
Wang, Tao; Gardiner, Bruce S.; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B.; Wang, Allan; Xu, Jiake
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-?2. This study demonstrates EGR1 involvement in adult tendon formation, healing, and repair and identifies Egr1 as a putative target in tendon repair strategies.
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
Degeneration of tendon tissue is a common cause of tendon dysfunction with the symptoms of repeated episodes of pain and palpable increase of tendon thickness. Tendon mechanical properties are directly related to its physiological composition and the structural organization of the interior collagen fibers which could be altered by tendon degeneration due to overuse or injury. Thus, measuring mechanical properties
Injured rat Achilles tendons were treated with botulism toxin to create a mechanically unloaded condition (unloaded) or left untreated (loaded), and then treated with phosphate-buffered saline (PBS), platelet-rich plasma (PRP), tendon stem cells (TSCs), or a combination (TSCs?+?PRP). mRNA and protein expression of collagen I, collagen III, tenascin C, and Smad 8 were determined by real time PCR and immunostaining, respectively. Loaded tendons treated with PBS, PRP, or TSCs for 3 or 14 days had higher collagen I mRNA expression than unloaded tendons. Loaded tendons treated with PBS for 3 or 14 days or with PRP for 3 days had higher collagen I protein levels than unloaded tendons. Loaded tendons treated for 3 days with PBS, for 14 days with PRP or TSCs or TSCs?+?PRP for 3 or 14 days had higher collagen III protein levels than unloaded tendons. Collagen I mRNA levels were higher in TSCs?+?PRP-treated loaded tendons compared to PBS-treated loaded tendons on day 3 of treatment. Based on changes in the expression of tendon-healing genes, our data suggest that the combination of TSCs and PRP has synergistic effects on tendon healing under both loaded and unloaded conditions, and loaded conditions improve tendon healing. PMID:22161871
Chen, Lei; Dong, Shi-Wu; Liu, Jun-Peng; Tao, Xu; Tang, Kang-Lai; Xu, Jian-Zhong
Tendon is a strong connective tissue that transduces muscle-generated forces into skeletal motion. In fulfilling this role, tendons are subjected to repeated mechanical loading and high stress, which may result in injury. Tissue engineering with stem cells offers the potential to replace injured/damaged tissue with healthy, new living tissue. Critical to tendon tissue engineering is the induction and guidance of stem cells towards the tendon phenotype. Typical strategies have relied on adult tissue homeostatic and healing factors to influence stem cell differentiation, but have yet to achieve tissue regeneration. A novel paradigm is to use embryonic developmental factors as cues to promote tendon regeneration. Embryonic tendon progenitor cell differentiation in vivo is regulated by a combination of mechanical and chemical factors. We propose that these cues will guide stem cells to recapitulate critical aspects of tenogenesis and effectively direct the cells to differentiate and regenerate new tendon. Here, we review recent efforts to identify mechanical and chemical factors of embryonic tendon development to guide stem/progenitor cell differentiation toward new tendon formation, and discuss the role this work may have in the future of tendon tissue engineering. PMID:24484642
Glass, Zachary A; Schiele, Nathan R; Kuo, Catherine K
Tendon properties contribute to the complex interaction of the central nervous system, muscle–tendon unit and bony structures to produce joint movement. Until recently limited information on human tendon behaviour in vivo was available; however, novel methodological advancements have enabled new insights to be gained in this area. The present review summarizes the progress made with respect to human tendon and aponeurosis function in vivo, and how tendons adapt to ageing, loading and unloading conditions. During low tensile loading or with passive lengthening not only the muscle is elongated, but also the tendon undergoes significant length changes, which may have implications for reflex responses. During active loading, the length change of the tendon far exceeds that of the aponeurosis, indicating that the aponeurosis may more effectively transfer force onto the tendon, which lengthens and stores elastic energy subsequently released during unloading, in a spring-like manner. In fact, data recently obtained in vivo confirm that, during walking, the human Achilles tendon provides elastic strain energy that can decrease the energy cost of locomotion. Also, new experimental evidence shows that, contrary to earlier beliefs, the metabolic activity in human tendon is remarkably high and this affords the tendon the ability to adapt to changing demands. With ageing and disuse there is a reduction in tendon stiffness, which can be mitigated with resistance exercises. Such adaptations seem advantageous for maintaining movement rapidity, reducing tendon stress and risk of injury, and possibly, for enabling muscles to operate closer to the optimum region of the length–tension relationship.
Magnusson, S Peter; Narici, Marco V; Maganaris, Constantinos N; Kjaer, Michael
Pathologic processes intrinsic and extrinsic to the tendons have been proposed as the underlying cause of rotator cuff disease, but the precise etiology is not known. Tear formation is, in part, attributable to the accumulation of subrupture tendon fatigue damage. We review the molecular, mechanical, and structural changes induced in tendons subjected to controlled amounts of fatigue loading in an animal model of early tendinopathy. The distinct tendon responses to low and moderate levels of loading, as opposed to high levels, provide insight into the potential mechanisms for the therapeutic benefits of exercise in the treatment of rotator cuff tendinopathy. The progression of damage accumulation leading to fiber rupture and eventual tendon tearing seen with higher loading illustrates the progression from tendinopathy to full-thickness tearing. We hope that this more realistic animal model of tendon fatigue damage will allow better assessment of biologic, mechanical, tissue-engineering, and rehabilitation strategies to improve repair success.
Neviaser, Andrew; Andarawis-Puri, Nelly; Flatow, Evan
Background While a great deal is known regarding the performance of muscle with intact tendon, little is known about muscle performance when tendon is surgically lengthened or shortened. This knowledge may allow surgeons to more accurately predict functional outcome following tendon repair when correcting a simple tendon laceration or performing a more complex vascularized neuromuscular transfer. Materials and Methods We studied muscle performance 12 weeks following extensor tendon repairs producing altered tendon lengths. Forty male Fischer 344 rats underwent division of the proximal and distal tendons of the extensor digitorum longus muscle. Tendons were immediately repaired producing tendons with increased length, decreased length, or pre-surgical length (control). Observation confirmed that altered tendon length produced inverse changes in initial resting muscle tension. Results Muscle in the Decreased Tendon Length group demonstrated a 15.2% greater muscle mass, 4.9% greater muscle length, 9.6% greater physiologic cross-sectional area, 12.6% greater maximum isometric force, and 31.9% greater maximum power relative to the Control Tendon Length group (p < 0.05). The Increased Tendon Length group did not differ significantly from the Control Tendon Length group for any measurement. Histologically, muscles set with a decreased tendon length demonstrated normal appearing hypertrophied fibers, without evidence of detrimental histological effects such as fibrosis, denervation, necrosis, inflammation, fiber type changes, or fiber splitting. Conclusion These data support the clinical practice of setting muscles with increased passive tension when performing tendon transfer surgeries. Conversely, setting muscles with decreased tension does not necessarily result in a force or power deficit.
Krochmal, Daniel J.; Kuzon, William M.; Urbanchek, Melanie G.
The typical badminton player with an Achilles tendon rupture is 36 years old and, despite limbering up, is injured at the rear line in a sudden forward movement. He resumes work within three months and has a slight lack of dorsiflexion in the ankle as the main complication. Most patients resume badminton within one year, but some finish their sports career, mainly due to fear of a new injury. The investigation discusses predisposing factors and prophylactic measures.
Kaalund, S; Lass, P; H?gsaa, B; N?hr, M
The surgical approach of severe insertional Achilles tendonitis involves debridement, repair, and reattachment. Previously described techniques for bone-tendon reattachment involved the use of suture anchors in the sparsely trabeculated calcaneus. The following technique tip is a reintroduction of bicortical transosseous fixation previously used in rotator cuff repairs. Bone tunnels are a viable option in the treatment of insertional Achilles tendonitis; however, additional research is necessary to validate its efficacy in this application. PMID:22841157
Sundararajan, Priya Ponnapula
This paper describes the design and use of a novel system for quantification of active tendon forces. An arthroscopically implantable force probe (AIFP) was inserted arthroscopically into the subscapularis tendon of the shoulder in vivo. The output response of this device was calibrated in situ with known forces applied to the tendon using an arthroscopic technique. On recovery of motor
Anthony M. J. Bull; Peter Reilly; Andrew L. Wallace; Andrew A. Amis; Roger J. H. Emery
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.
Fractures of ossified tibialis anterior tendon have been successfully managed by the excision of the ossified tendon and transfer of the extensor hallucis longus tendon. A 64-year-old man sustained an injury during mountain hiking 2 weeks prior to presentation, falling down on his heels with his ankle fully plantarflexed. Two tender and bony hard masses were palpable along the course of the tibialis anterior tendon, one at the anteromedial aspect of the ankle and another at the dorsum of the talonavicular joint. Radiographs of the ankle demonstrated an approximately 2x1-cm ovoid-shaped bony mass at the anterior aspect of the ankle joint and another bony mass of similar size and shape at the dorsal aspect of the talonavicular joint. He underwent operative exploration, and complete rupture of the tendon through a bony mass was observed. The gap between the torn ends of the tendon after excision of the mass was too long to be repaired directly. Extensor hallucis longus tendon was retrieved 1 cm proximal to the metatarsophalangeal joint and was passed through the insertion of the anterior tibial tendon and pulled proximally and sutured to itself with the ankle in neutral. At 1 year after surgery, plain radiographs and ultrasonography showed no recurrence of calcification or ossification in the tendon and good mobility of the tibialis anterior muscle was observed. PMID:19301787
Lee, Woo-Chun; Moon, Jeong-Seok; Kim, Ji-Yeong; Ko, Hyeong-Tak
Injured tendons heal slowly and often result in the formation of mechanically and functionally inferior fibrotic scar tissue or fibrous adhesions. This study investigated the use of tendon-derived stem cells (TDSCs) for tendon repair in a rat patellar tendon window defect model. Fibrin glue constructs with or without GFP-TDSCs were transplanted into the window defect. The patellar tendons were harvested for histology, ex vivo fluorescent imaging and biomechanical test at various time points up to week 4. Our results showed that TDSCs significantly enhanced tendon healing as indicated by the increase in collagen production as shown by hematolxylin stain-ability of the tissue, improvement of cell alignment, collagen fiber alignment and collagen birefringence typical of tendon. The labeled cells were observed at weeks 1 and 2 and became almost undetectable at week 4. Both the ultimate stress and Young's modulus were significantly higher in the TDSCs group compared to those in the fibrin glue group at week 4. In conclusion, TDSCs promoted earlier and better repair in a rat patellar tendon window defect model. PMID:21928428
Ni, Ming; Lui, Pauline Po Yee; Rui, Yun Feng; Lee, Yuk Wa; Lee, Yuk Wai; Tan, Qi; Wong, Yin Mei; Kong, Siu Kai; Lau, Pui Man; Li, Gang; Chan, Kai Ming
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
G. Thomas; A. Brown
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
Graham H. Thomas; Albert E. Brown
Diagnosis and treatment of longitudinal tears of the tibialis anterior tendon are not well documented in the surgical literature. Described here is successful primary surgical repair of a longitudinally torn tibialis anterior tendon in a 60-year-old woman. PMID:16037556
Hamilton, Graham A; Ford, Lawrence A
Injuries to the tendon (e.g., wrist tendonitis, epicondyltis) due to overuse are common in sports activities and the workplace. Most are associated with repetitive, high force hand activities. The mechanisms of cellular and structural damage due to cyclical loading are not well known. The purpose of this video is to present a new system that can simultaneously load four tendons in tissue culture. The video describes the methods of sterile tissue harvest and how the tendons are loaded onto a clamping system that is subsequently immersed into media and maintained at 37°C. One clamp is fixed while the other one is moved with a linear actuator. Tendon tensile force is monitored with a load cell in series with the mobile clamp. The actuators are controlled with a LabView program. The four tendons can be repetitively loaded with different patterns of loading, repetition rate, rate of loading, and duration. Loading can continue for a few minutes to 48 hours. At the end of loading, the tendons are removed and the mid-substance extracted for biochemical analyses. This system allows for the investigation of the effects of loading patterns on gene expression and structural changes in tendon. Ultimately, mechanisms of injury due to overuse can be studies with the findings applied to treatment and prevention.
Asundi, Krishna; Rempel, David
Injuries to the tendon (e.g., wrist tendonitis, epicondyltis) due to overuse are common in sports activities and the workplace. Most are associated with repetitive, high force hand activities. The mechanisms of cellular and structural damage due to cyclical loading are not well known. The purpose of this video is to present a new system that can simultaneously load four tendons in tissue culture. The video describes the methods of sterile tissue harvest and how the tendons are loaded onto a clamping system that is subsequently immersed into media and maintained at 37 degrees C. One clamp is fixed while the other one is moved with a linear actuator. Tendon tensile force is monitored with a load cell in series with the mobile clamp. The actuators are controlled with a LabView program. The four tendons can be repetitively loaded with different patterns of loading, repetition rate, rate of loading, and duration. Loading can continue for a few minutes to 48 hours. At the end of loading, the tendons are removed and the mid-substance extracted for biochemical analyses. This system allows for the investigation of the effects of loading patterns on gene expression and structural changes in tendon. Ultimately, mechanisms of injury due to overuse can be studies with the findings applied to treatment and prevention. PMID:18979013
Asundi, Krishna; Rempel, David
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
Atesok, Kivanc; Fu, Freddie H; Wolf, Megan R; Ochi, Mitsuo; Jazrawi, Laith M; Doral, M Nedim; Lubowitz, James H; Rodeo, Scott A
The load-strain and stress-relaxation behavior of wet rat tail tendon has been examined with respect to the parameters strain, rate of strain- ing, and temperature. It is found that this mechanical behavior is reproducible after resting tile tendon for a few minutes after each extension so long as the strain does not exceed about 4 per cent. If this strain
BERNARD J. RIGBY; OHN D. SPIKES; HENRY EYRING
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
Breidenbach, Andrew P; Gilday, Steven D; Lalley, Andrea L; Dyment, Nathaniel A; Gooch, Cynthia; Shearn, Jason T; Butler, David L
The Achilles tendon is believed to have first developed two million years ago enabling humans to run twice as fast. However if the Achilles tendon is so important in terms of evolution, then why is this tendon so prone to injury – especially for those more active like athletes. The Achilles tendon had an integral role in evolving apes from
S. Malvankar; W. S. Khan
A histologically normal insertion site does not regenerate following rotator cuff tendon-to-bone repair, which is likely due to abnormal or insufficient gene expression and/or cell differentiation at the repair site. Techniques to manipulate the biologic events following tendon repair may improve healing. We used a sheep infraspinatus repair model to evaluate the effect of osteoinductive growth factors and BMP-12 on tendon-to-bone healing. Magnetic resonance imaging and histology showed increased formation of new bone and fibrocartilage at the healing tendon attachment site in the treated animals, and biomechanical testing showed improved load-to-failure. Other techniques with potential to augment repair site biology include use of platelets isolated from autologous blood to deliver growth factors to a tendon repair site. Modalities that improve local vascularity, such as pulsed ultrasound, have the potential to augment rotator cuff healing. Important information about the biology of tendon healing can also be gained from studies of substances that inhibit healing, such as nicotine and antiinflammatory medications. Future approaches may include the use of stem cells and transcription factors to induce formation of the native tendon-bone insertion site after rotator cuff repair surgery.
Tendon transfer procedures are useful for replacing a dysfunctional or diseased tendon or for restoring muscle imbalance. The tendon to be transferred is harvested as distal as is necessary to provide adequate length for rerouting and attachment at the different site. The harvesting of tendon itself can be attained using an open surgical approach or minimally invasive percutaneous techniques that limit surgical exposure. This article describes percutaneous techniques for tendon transfer procedures used to address foot and ankle disorders. PMID:24548514
Panchbhavi, Vinod Kumar
Tendon healing is fraught with complications such as reruptures and adhesion formation due to the formation of scar tissue at the injury site as opposed to the regeneration of native tissue. Stem cells are an attractive option in developing cell-based therapies to improve tendon healing. However, several questions remain to be answered before stem cells can be used clinically. Specifically, the type of stem cell, the amount of cells, and the proper combination of growth factors or mechanical stimuli to induce differentiation all remain to be seen. This paper outlines the current literature on the use of stem cells for tendon augmentation.
Gulotta, Lawrence V.; Chaudhury, Salma; Wiznia, Daniel
Despite various attempts to repair and replace injured tendon, an understanding of the repair processes and a systematic approach to achieving functional efficacy remain elusive. In this review the epidemiology of tendon injury and repair is first examined. Using a traditional paradigm for repair assessment, the biology and biomechanics of normal tendon, natural healing, and repair are then explored. New treatment strategies such as functional tissue engineering are discussed, including a functional approach to treatment that involves the development of in vivo functional design parameters to judge the acceptability of a repair outcome. The paper concludes with future directions. PMID:15255772
Butler, David L; Juncosa, Natalia; Dressler, Matthew R
This paper aims to highlight the need for a refined tendon model to reproduce the main mechanical features of the integrated\\u000a muscle–tendon unit (MTU). Elastic nonlinearities of the tendon, both at the nano and microscale, are modeled by a multiscale\\u000a approach, accounting for the hierarchical arrangement (from molecules up to the fibers) of the collagen structures within\\u000a the tissue. This
Franco Maceri; Michele Marino; Giuseppe Vairo
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.
Ag?r, Ismail; Aytekin, Mahmut Nedim; Basc?, Onur; Cayp?nar, Bar?s; Erol, Bulent
[Purpose] The purpose of this study was to investigate differences in upper extremity muscle activities of women college students' due to method of bag-carrying and weight. [Subjects] Thirty healthy adult females participated in this study. The exclusion criteria were orthopedic or neurologic disease, or a dominant left side. [Methods] Electromyographic activities of the supraspinatus and upper trapezius were recorded bilaterally under two conditions: crossbody bag, ipsilateral bag. [Results] There were no significant differences in the supraspinatus and upper trapezius muscles according to the weight carried; however, there was significant difference in the right supraspinatus and both upper trapezius muscles according to the method of carrying. [Conclusion] An effective backpack safety program for female college students is necessary to educate them how to prevent possible musculoskeletal pain related to the weight carried and the method of carrying from the perspective of an ergonomical approach.
Cho, Sung-Hyoun; Lee, Jung-Ho; Kim, Cheol-Yong
Tendon injuries are common in hand wounds and their functional consequences are not negligible. In emergency, tendon repairs techniques are well codified to restore function. These tendon repairs can be made in one session, in two sessions, or even use tendon transfers. Tendon transfers are not usual in the emergency but more common in the treatment of sequelae or failure of primary repair. We report one case of transfer to restore thumb flexion in emergency. PMID:23499269
Mesnil, P; Szymanski, C; Fontaine, C; Chantelot, C
We present the case of a patient with flexor digitorum profundus tendon laceration at the A2 pulley level caused by an injury to the base of the right ring finger by a knife. The patient was treated by flexor tendon reconstruction from the palm to the fingertip by using the left second toe flexor tendon as a graft, which improved the active range of motion. Further improvement was achieved by subsequent tenolysis, which eventually restored nearly normal function. Our experience with this case indicates that the intrasynovial tendon is a reasonable graft source for the synovial space in fingers and may enable restoration of excellent postoperative function.
Sasaki, Jun; Itsubo, Toshiro; Nakamura, Koichi; Hayashi, Masanori; Uchiyama, Shigeharu; Kato, Hiroyuki
Sonoelastography is a newly introduced ultrasound technique that evaluates tissue elasticity and thus provides additional information to that offered by conventional ultrasound images. In the musculoskeletal field, sonoelastography can help improve estimation of tendon stiffness. In this article, the principles and future developments of sonoelastography are discussed using the strongest and thickest tendon of the human body, the Achilles tendon, for illustrative purposes. Preliminary findings of sonoelastography in healthy and pathological Achilles tendons, technical considerations, examination technique and several limitations are addressed. The usefulness of elastography can be expected to increase rapidly in the musculoskeletal field, as soon as we learn to interpret elastographic artifacts as well as to take advantage of the new information provided by sonoelastography. PMID:20539957
Klauser, Andrea S; Faschingbauer, Ralph; Jaschke, Werner R
A histologically normal insertion site does not regenerate following rotator cuff tendon-to-bone repair, which is likely due\\u000a to abnormal or insufficient gene expression and\\/or cell differentiation at the repair site. Techniques to manipulate the biologic\\u000a events following tendon repair may improve healing. We used a sheep infraspinatus repair model to evaluate the effect of osteoinductive\\u000a growth factors and BMP-12 on
David Kovacevic; Scott A. Rodeo
When splitting a metacarpal pulley, a diagonal incision allows, after sliding its margins and suturing them, to restore a pulley larger than before. With a small counter incision, it is possible to have a yet larger one. It is a very proper way to treat a "trigger finger". A similar technique may be used in flexor tendons lacerations, which make possible the suture of both tendons. This technique permits the tenolysis with pulley reconstruction. PMID:9382649
Kapandji, I A
Three patients were seen for pain and snapping over their medial knee during active knee flexion and extension. Physical examination\\u000a revealed an audible and visible subluxation that was localized to the posteromedial aspect of their symptomatic knee. One\\u000a patient underwent a semitendinosus tendon harvest, and two patients underwent a release of their semitendinosus and gracilis\\u000a tendons. All three patients had
Andrew G. Geeslin; Robert F. LaPrade
Information for all cattle with a diagnosis of tendon injury entered into the Veterinary Medical Data Base (VMDB) was retrieved and selected medical records reviewed. The proportional morbidity rate for tendon disruption was 0.89 cattle/1,000 cattle admissions and 95 of 99 cattle survived. Female and dairy cattle had a greater risk of tendon disruption than male or beef cattle, respectively. Also, cattle 6 months to 7 years old had a greater risk than cattle younger than 6 months old. Complete medical records were examined for 27 cattle. Affected cattle were 2.5 +/- 1.8 years old and weighed 593.6 +/- 315.6 kg. Injuries were most commonly caused by accidents involving farm machinery (72%). Unilateral superficial digital flexor tendon injury occurred in 8 cattle (30%); multiple tendon injury occurred in the other 19 cattle (70%). A single limb was involved in 25 cattle, a rear limb was involved in 24 cattle, and an open wound was associated with the injury in 26 cattle. Wounds were identified most commonly at the mid (13 cattle) and proximal metatarsus (4 cattle). Treatment of tendon disruption included tenorrhaphy and casting (9 cattle), external coaptation, alone, (14 cattle), stall confinement, alone, (1 cow), and euthanasia or salvage (3 cattle). External coaptation was maintained for 74.4 +/- 34.3 days, and total confinement period was 88.3 +/- 59.5 days. Short-term complications included severe tendon laxity (one cow) and fatal septic peritonitis (one bull). Twenty-two of 24 cattle treated for tendon disruption survived. Follow-up information was available for 16 cattle; 14 cattle (87%) returned to productivity and 11 of 15 cattle with long-term follow-up (73%) were considered productive. Long-term complications included persistent lameness (56%) and persistent hyperextension of the digits (19%). PMID:8810022
Anderson, D E; St-Jean, G; Morin, D E; Ducharme, N G; Nelson, D R; Desrochers, A
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.
Abdallah, Muhammad E. (Inventor); Platt, Robert (Inventor); Wampler, II, Charles W. (Inventor)
Background Long head biceps (LHB) degeneration, in combination with rotator cuff tears, can be a source of chronic shoulder pain. LHB tenotomy reduces pain and improves joint function although the pathophysiological context is not well understood. Tendon integrity depends on the extracellular matrix (ECM), which is regulated by matrix metalloproteinases (MMP). It is unclear which of these enzymes contribute to LHB but we chose to study MMP 1, 3, and 9 and hypothesized that one or more of them may be altered in LHB, whether diagnosed preoperatively or intraoperatively. We compared expression of these MMPs in both LHB and healthy tendon samples. Methods LHB samples of 116 patients with degenerative rotator cuff tears were harvested during arthroscopic tenotomy. Patients were assigned to 4 groups (partial thickness tear, full thickness tear, cuff arthropathy, or control) based upon intraoperative findings. Partial and full thickness tears were graded according to Ellman and Bateman's classifications, respectively. MMP expression was determined by immunohistochemistry. Results MMP 1 and 9 expression was significantly higher in the presence of rotator cuff tears than in controls whereas MMP 3 expression was significantly decreased. MMP 1 and 9 expression was significantly higher in articular-sided than bursal-sided partial thickness tears. No significant association was found between MMP 1 and 9 expression and full thickness tears, and the extent of the cuff tear by Bateman's classification. Conclusion Increased MMP 1 and 9 expression, and decreased MMP 3 expression are found in LHB degeneration. There is a significant association between the size and location of a rotator cuff tear and MMP expression.
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.
Wong, J.K.F.; Alyouha, S.; Kadler, K.E.; Ferguson, M.W.J.; McGrouther, D.A.
In the present experiment we obtained the tensile properties of the human gastrocnemius tendon, a high-stressed tendon suitable for spring-like action during locomotion. Measurements were taken in vivo in six men. The gastrocnemius tendon elongation during tendon loading-unloading induced by muscle contraction-relaxation was measured using real-time ultrasonography. Tendon forces were calculated from the moment generated during isometric plantarflexion contraction, using tendon moment arm length data obtained in vivo with the tendon travel method. Tendon stiffness data were calculated from the slope of the tendon force-elongation curve, and were then normalized to the tendon's original dimensions, obtained from morphometric analysis of sonographs, to estimate the tendon Young's modulus. Mechanical hysteresis values were obtained from area calculations by numerical integration. The elongation of the tendon increased curvilinearly with the force acting upon it, from 1.7+/-1mm (0.8+/-0.3% strain) at 87.5+/-8.5 N to 11.1+/-3.1mm (4.9+/-1% strain) at 875+/-85 N. The tendon Young's modulus and mechanical hysteresis were 1.16+/-0.15 GPa and 18+/-3%, respectively. These values fall within the range of values obtained from in vitro experiments and are very similar to the respective values recently obtained from in vivo measurements in the less highly stressed human tibialis anterior tendon (1.2 GPa and 19%), thus indicating that the material properties of tendon are independent of physiological loading and function. Combining the present tendon force-elongation data with previously reported Achilles tendon force data recorded during walking indicates that the gastrocnemius tendon would provide approximately 6% of the total external work produced by the locomotor system. This estimate illustrates the contribution of passive elastic mechanisms on the economy and efficiency of walking. The contributions would be greater in more active exercise such as running. PMID:12445617
Maganaris, Constantinos N; Paul, John P
The Achilles tendon is believed to have first developed two million years ago enabling humans to run twice as fast. However if the Achilles tendon is so important in terms of evolution, then why is this tendon so prone to injury - especially for those more active like athletes. The Achilles tendon had an integral role in evolving apes from a herbivorous diet to early humans who started hunting for food over longer distances, resulting in bipedal locomotion. Evolutionary advantages of the Achilles tendon includes it being the strongest tendon in the body, having an energy-saving mechanism for fast locomotion, allows humans to jump and run, and additionally is a spring and shock absorber during gait. Considering these benefits it is therefore not surprising that studies have shown athletes have thicker Achilles tendons than subjects who are less active. However, contradictory to these findings that show the importance of the Achilles tendon for athletes, it is well known that obtaining an Achilles tendon injury for an athlete can be career-altering. A disadvantage of the Achilles tendon is that the aetiology of its pathology is complicated. Achilles tendon ruptures are believed to be caused by overloading the tensed tendon, like during sports. However studies have also shown athlete Achilles tendon ruptures to have degenerative changes in the tendon. Other flaws of the Achilles tendon are its non-uniform vascularity and incomplete repair system which may suggest the Achilles tendon is on the edge of evolution. Research has shown that there is a genetic influence on the predisposition a person has towards Achilles tendon injuries. So if this tendon is here to stay in our anatomy, and it probably is due to the slow rate of evolution in humans, research in genetic modification could be used to decrease athletes' predisposition to Achilles tendinopathy. PMID:21900004
Malvankar, S; Khan, W S
Tendons transfer force from muscle to bone. Specific tendons, including the equine superficial digital flexor tendon (SDFT), also store and return energy. For efficient function, energy-storing tendons need to be more extensible than positional tendons such as the common digital extensor tendon (CDET), and when tested in vitro have a lower modulus and failure stress, but a higher failure strain. It is not known how differences in matrix organization contribute to distinct mechanical properties in functionally different tendons. We investigated the properties of whole tendons, tendon fascicles and the fascicular interface in the high-strain energy-storing SDFT and low-strain positional CDET. Fascicles failed at lower stresses and strains than tendons. The SDFT was more extensible than the CDET, but SDFT fascicles failed at lower strains than CDET fascicles, resulting in large differences between tendon and fascicle failure strain in the SDFT. At physiological loads, the stiffness at the fascicular interface was lower in the SDFT samples, enabling a greater fascicle sliding that could account for differences in tendon and fascicle failure strain. Sliding between fascicles prior to fascicle extension in the SDFT may allow the large extensions required in energy-storing tendons while protecting fascicles from damage.
Thorpe, Chavaunne T.; Udeze, Chineye P.; Birch, Helen L.; Clegg, Peter D.; Screen, Hazel R. C.
Rotator cuff tears can cause irreversible changes (e.g., fibrosis) to the structure and function of the injured muscle(s). Fibrosis leads to increased muscle stiffness resulting in increased tension at the rotator cuff repair site. This tension influences repairability and healing potential in the clinical setting. However, the micro- and meso-scale structural and molecular sources of these whole-muscle mechanical changes are poorly understood. Here, single muscle fiber and fiber bundle passive mechanical testing was performed on rat supraspinatus and infraspinatus muscles with experimentally induced massive rotator cuff tears (Tenotomy) as well as massive tears with chemical denervation (Tenotomy?+?BTX) at 8 and 16 weeks post-injury. Titin molecular weight, collagen content, and myosin heavy chain profiles were measured and correlated with mechanical variables. Single fiber stiffness was not different between controls and experimental groups. However, fiber bundle stiffness was significantly increased at 8 weeks in the Tenotomy?+?BTX group compared to Tenotomy or control groups. Many of the changes were resolved by 16 weeks. Only fiber bundle passive mechanics was weakly correlated with collagen content. These data suggest that tendon injury with concomitant neuromuscular compromise results in extra-cellular matrix production and increases in stiffness of the muscle, potentially complicating subsequent attempts for surgical repair. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1111-1116, 2014. PMID:24838823
Sato, Eugene J; Killian, Megan L; Choi, Anthony J; Lin, Evie; Esparza, Mary C; Galatz, Leesa M; Thomopoulos, Stavros; Ward, Samuel R
For both tendon allografts and autografts, the surface, initially optimized for gliding, may not be ideal to facilitate tissue integration for graft healing to host tendon or bone. As a prelude to studying tendon-bone integration, we investigated the effect of surface treatments with trypsin or mechanical abrasion on cell attachment to the tendon surface in a canine ex vivo intrasynovial tendon tissue culture model. Intrasynovial tendon allograft surfaces were seeded with cells after the following treatments: 1) no treatment, 2) mechanical abrasion, 3) trypsin, 4) abrasion and trypsin. The area covered by cells was determined using confocal laser microscopy at one and two weeks. Results were compared to untreated extrasynovial tendon. Additional tendons were characterized with scanning electron microscopy. Tendons with trypsin treatment had significantly more surface coverage with cells than the other groups, after both one and two weeks of culture. In terms of the cellular shape and size, cells on tendons with trypsin treatment spread more and were more polygonal in shape, whereas tendons with mechanical abrasion with/without trypsin treatment contained smaller, more spindle-like cells. Surface roughening can affect cell behavior with topographical stimulation. Trypsin surface digestion exposes a mesh-like structure on the tendon surface, which could enhance cell adherence and, possibly, tendon/bone healing.
Hashimoto, Takahiro; Sun, Yu-Long; An, Kai-Nan; Amadio, Peter C.; Zhao, Chunfeng
An investigation was carried out on the sheaths which envelop rat tail tendons. The samples were processed for observation by light and electron microscopy. In the case of electron microscopy, thin sections of specimens embedded in epoxy resin and replicas of freeze etched samples were used. On the basis of histological and ultrastructural observations, four distinct connective tissue sheaths have been detected. The paratendineum is a thick fibrous sheath that covers externally the four groups of tendons arranged around the vertebrae of the tail; the epitendineum is a distinct fibrous sheath surrounding each tendon group; the peritendineum is composed of concentric cellular laminae enveloping each tendon; lastly, the endotendineum is made up of one cellular lamella which adheres to the fibres of the tendon, projecting trabeculae between the individual tendon fascicles. In the para- and epitendineum, thick bundles of collagen fibrils, running parallel to the fibres of the tendon, were visible. The collagen fibrils had a wide variability of diameters (from 35 to 220 nm) and, when examined in replica, their microfibrillar arrangement appeared to be straight. In the peri- and endotendineum, thin bundles of collagen fibrils were visible between the cellular laminae, parallel to the main axis of the tendon. Among these collagen bundles, elastic fibres and numerous glycoproteins containing microfibril-like filaments were visible. The collagen fibrils were small and of uniform diameter (50 nm) and, when observed on replica, showed a helicoidal microfibrillar arrangement. The cell layers of the peri- and endotendineum were made up of flattened fibroblasts which were connected by specialised junctions and which contained numerous micropinocytotic vesicles. A thin layer of granular electron-dense material, with ultrastructural characteristics similar to those of a basement membrane, was visible on the surface of the most external cellular layer of the peritendineum and on the outer surface of the cellular lamella of the endotendineum. Due to their morphological characteristics it is supposed that the four tendon sheaths are involved in different and special functions. Moreover, collagen Type I and collagen Type III, demonstrated by means of immunofluorescence techniques in previous investigations, show respectively a close similarity in distribution to the thick collagen fibrils, with a straight microfibrillar arrangement, of the two external sheaths, and to the thin collagen fibrils, with a helicoidal microfibrillar arrangement, of the two internal sheaths. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9
Strocchi, R; Leonardi, L; Guizzardi, S; Marchini, M; Ruggeri, A
...SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices Â§ 888.3025 Passive tendon prosthesis. (a...use in the surgical reconstruction of a flexor tendon of the hand. The device is implanted for a period of 2 to 6...
...SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices Â§ 888.3025 Passive tendon prosthesis. (a...use in the surgical reconstruction of a flexor tendon of the hand. The device is implanted for a period of 2 to 6...
Whether adjacent collagen fascicles transmit force in parallel is unknown. The purpose of the present study was to examine the magnitude of lateral force transmission between adjacent collagen fascicles from the human patellar and Achilles tendon. From each sample two adjacent strands of fascicles (phi 300-530 mum) enclosed in a fascicular membrane were dissected. The specimen was deformed to approximately 3% strain in three independent load-displacement cycles in a small-scale tensile testing device. Cycle 1: the fascicles and the fascicular membrane were intact. Cycle 2: one fascicle was transversally cut while the other fascicle and the fascicular membrane were kept intact. Cycle 3: both fascicles were cut in opposite ends while the fascicular membrane was left intact. A decline in peak force of 45% and 55% from cycle 1 to cycle 2, and 93% and 92% from cycle 2 to cycle 3 was observed in the patellar and Achilles tendon fascicles, respectively. A decline in stiffness of 39% and 60% from cycle 1 to cycle 2, and of 93% and 100% from cycle 2 to cycle 3 was observed in the patellar and Achilles tendon fascicles, respectively. The present data demonstrate that lateral force transmission between adjacent collagen fascicles in human tendons is small or negligible, suggesting that tendon fascicles largely act as independent structures and that force transmission principally takes place within the individual fascicles. PMID:17931846
Haraldsson, Bjarki T; Aagaard, Per; Qvortrup, Klaus; Bojsen-Moller, Jens; Krogsgaard, Michael; Koskinen, Satu; Kjaer, Michael; Magnusson, S Peter
Tendons transmit forces generated from muscle to bone making joint movements possible. Tendon collagen has a complex supramolecular structure forming many hierarchical levels of association; its main functional unit is the collagen fibril forming fibers and fascicles. Since tendons are enclosed by loose connective sheaths in continuity with muscle sheaths, it is likely that tendon sheaths could play a role in absorbing/transmitting the forces created by muscle contraction. In this study rat Achilles tendons were passively stretched in vivo to be observed at polarized light microscope (PLM), scanning electron microscope (SEM) and transmission electron microscope (TEM). At PLM tendon collagen fibers in relaxed rat Achilles tendons ran straight and parallel, showing a periodic crimp pattern. Similarly tendon sheaths showed apparent crimps. At higher magnification SEM and TEM revealed that in each tendon crimp large and heterogeneous collagen fibrils running straight and parallel suddenly changed their direction undergoing localized and variable modifications. These fibril modifications were named fibrillar crimps. Tendon sheaths displayed small and uniform fibrils running parallel with a wavy course without any ultrastructural aspects of crimp. Since in passively stretched Achilles tendons fibrillar crimps were still observed, it is likely that during the tendon stretching, and presumably during the tendon elongation in muscle contraction, the fibrillar crimp may be the real structural component of the tendon crimp acting as shock absorber. The peritendinous sheath can be stretched as tendon, but is not actively involved in the mechanism of shock absorber as the fibrillar crimp. The different functional behaviour of tendons and sheaths may be due to the different structural and molecular arrangement of their fibrils. PMID:17703588
Franchi, M; Quaranta, M; De Pasquale, V; Macciocca, M; Orsini, E; Trirè, A; Ottani, V; Ruggeri, A
The purpose of the current review is to highlight the structure-function relationship of tendons and related structures to provide an overview for readers whose interest in tendons needs to be underpinned by anatomy. Because of the availability of several recent reviews on tendon development and entheses, the focus of the current work is primarily directed towards what can best be described as the ‘tendon proper’ or the ‘mid-substance’ of tendons. The review covers all levels of tendon structure from the molecular to the gross and deals both with the extracellular matrix and with tendon cells. The latter are often called ‘tenocytes’ and are increasingly recognized as a defined cell population that is functionally and phenotypically distinct from other fibroblast-like cells. This is illustrated by their response to different types of mechanical stress. However, it is not only tendon cells, but tendons as a whole that exhibit distinct structure-function relationships geared to the changing mechanical stresses to which they are subject. This aspect of tendon biology is considered in some detail. Attention is briefly directed to the blood and nerve supply of tendons, for this is an important issue that relates to the intrinsic healing capacity of tendons. Structures closely related to tendons (joint capsules, tendon sheaths, pulleys, retinacula, fat pads and bursae) are also covered and the concept of a ‘supertendon’ is introduced to describe a collection of tendons in which the function of the whole complex exceeds that of its individual members. Finally, attention is drawn to the important relationship between tendons and fascia, highlighted by Wood Jones in his concept of an ‘ectoskeleton’ over half a century ago – work that is often forgotten today.
Benjamin, M; Kaiser, E; Milz, S
The purpose of this study was to compare the tensile strength of the central one third patellar tendon--as used for reconstruction of the anterior cruciate ligament--to that of the residual patellar tendon. Ten matched pairs of human cadaveric knees were used for this study, each specimen consisting of an intact patella-patellar tendon-proximal tibial unit. One knee from each pair was randomly selected for removal of both the medial and lateral one third of the patellar tendon, leaving the central one third intact. The contralateral knee of each pair underwent removal of the central one third of the patellar tendon, leaving the residual two thirds intact. Each specimen was then mounted in a materials testing machine and tensile tested to failure at a strain rate of 100%.s-1. The most important result to emerge from these experiments was that there was no significant difference in maximum force to failure for the residual patellar tendon compared to the central one third. Thus any thought that removal of the central one third as a graft still leaves a tendon twice as wide and therefore twice as strong as a graft is dispelled by these experiments. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5
Matava, M J; Hutton, W C
PURPOSE: The present study evaluated the presence of stem cells in hamstring tendons from adult subjects of different ages. The aim was to isolate, characterize and expand these cells in vitro, and to evaluate whether cell activities are influenced by age. METHODS: Tendon stem cells (TSCs) were isolated through magnetic sorting from the hamstring tendons of six patients. TSC percentage, morphology and clonogenic potential were evaluated, as well as the expression of specific surface markers. TSC multi-potency was also investigated as a function of age, and quantitative polimerase chain reaction was used to evaluate gene expression of TSCs cultured in suitable differentiating media. RESULTS: The presence of easily harvestable stem cell population within adult human hamstring tendons was demonstrated. These cells exhibit features such as clonogenicity, multi-potency and mesenchymal stem cells markers expression. The age-related variations in human TSCs affect the number of isolated cells and their self-renewal potential, while multi-potency assays are not influenced by tendon ageing, even though cells from younger individuals expressed higher levels of osteogenic and adipogenic genes, while chondrogenic genes were highly expressed in cells from older individuals. CONCLUSIONS: These results may open new opportunities to study TSCs to better understand tendon physiology, healing and pathological processes such as tendinopathy and degenerative age-related changes opening new frontiers in the management of tendinopathy and tendon ruptures. PMID:23503946
Ruzzini, Laura; Abbruzzese, Franca; Rainer, Alberto; Longo, Umile Giuseppe; Trombetta, Marcella; Maffulli, Nicola; Denaro, Vincenzo
Flexor tendon injuries still remain a challenging condition to manage to ensure optimal outcome for the patient. Since the first flexor tendon repair was described by Kirchmayr in 1917, several approaches to flexor tendon injury have enabled successful repairs rates of 70-90%. Primary surgical repair results in better functional outcome compared to secondary repair or tendon graft surgery. Flexor tendon injury repair has been extensively researched and the literature demonstrates successful repair requires minimal gapping at the repair site or interference with tendon vascularity, secure suture knots, smooth junction of tendon end and having sufficient strength for healing. However, the exact surgical approach to achieve success being currently used among surgeons is still controversial. Therefore, this review aims to discuss the results of studies demonstrating the current knowledge regarding the optimal approach for flexor tendon repair. Post-operative rehabilitation for flexor tendon surgery is another area, which has caused extensive debate in hand surgery. The trend to more active mobilisation protocols seems to be favoured but further study in this area is needed to find the protocol, which achieves function and gliding but avoids rupture of the tendons. Lastly despite success following surgery complications commonly still occur post surgery, including adhesion formation, tendon rupture and stiffness of the joints. Therefore, this review aims to discuss the appropriate management of these difficulties post surgery. New techniques in management of flexor tendon will also be discussed including external laser devices, addition of growth factors and cytokines. PMID:22431948
Griffin, M; Hindocha, S; Jordan, D; Saleh, M; Khan, W
We describe a novel technique of tubularizing flat tendons in tendon transfer procedures, including Jones procedure and Chrisman-Snook reconstruction. The technique strengthens the tendon, facilitates passage and fixation through bony tunnels, and helps protect it from fraying. PMID:18348833
Pace, Alistair; Dhar, Sunil
The central third of the patellar tendon of the right knee was removed in 40 adult New Zealand White (NZW) rabbits. The animals were divided into two groups of 20 animals each. In group 1 the tendon defect was left open and in group 2 the tendon defect was closed. The peritenon was closed in all cases. The animals were
Giuseppe Milano; Antonio Gigante; Alfredo Schiavone Panni; Pier Damiano Mulas; Carlo Fabbriciani
The snapping tendon syndrome may be caused by abnormalities of the fascia lata, gluteus maximus muscle, or less commonly, the iliopsoas tendon. One case is reported in which fluoroscopic monitoring after computed tomography-guided injection of contrast material confirmed the diagnosis of snapping iliopsoas tendon syndrome. PMID:3340787
Staple, T W; Jung, D; Mork, A
Phylogenetically, tendinous tissue first appears in the invertebrate chordate Branchiostoma as myosepta. This two-dimensional array of collagen fibers is highly organized, with fibers running along two primary axes. In hagfish the first linear tendons appear and the myosepta have developed specialized regions with unidirectional fiber orientation—a linear tendon within the flat sheet of myoseptum. Tendons react to compressive load by
Adam P. Summers; Thomas J. Koob
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.
Reverchon, Ernesto; Baldino, Lucia; Cardea, Stefano; De Marco, Iolanda
We report 22 patients (19 women and three men) of mean age 20.8 years who had painful snapping sensations in the groin. Most were able to reproduce the click by extending the affected hip from a flexed, abducted and externally rotated position and most were tender in the adductor triangle. Plain radiographs and an arthrogram were normal. A clinical diagnosis of subluxation of the iliopsoas tendon was made. Conservative management failed in 14 patients, two of whom had bilateral pain. All 14 had surgical release of the iliopsoas tendon through a medial approach. At follow-up (mean 17 months) the click had resolved in ten hips, was occasional but painless in five and unchanged in one. The syndrome of a painful 'snapping' psoas may result in disproportionately disabling symptoms. It may be diagnosed on clinical grounds and effectively treated, when severe, by release of the iliopsoas tendon. PMID:7593099
Taylor, G R; Clarke, N M
\\u000a \\u000a Background and Purpose:\\u000a Calcifying tendonitis is a degenerative inflammatory joint disorder. Pain relief can be successfully achieved with low-dose\\u000a radiotherapy. It is actually unknown which types of calcifying tendonitis respond to radiotherapy and which do not. The authors\\u000a tried to get predictive objectives for the response to radiotherapy on the basis of different morphological patterns of calcifications\\u000a evaluated by X-ray
Boris Adamietz; Rüdiger Schulz-Wendtland; Sedat Alibek; Michael Uder; Rolf Sauer; Oliver Ott; Ludwig Keilholz
Rupture of the Achilles tendon is a considerable cause of morbidity with reduced function following injury. Recent studies have shown little difference in outcome between the techniques of open and non-operative treatment using an early active rehabilitation programme. Meta-analyses have shown that non-operative management has increased risk of re-rupture whereas surgical intervention has risks of complications related to the wound and iatrogenic nerve injury. Minimally invasive surgery has been adopted as a way of reducing infections rates and wound breakdown however avoiding iatrogenic nerve injury must be considered. We discuss the techniques and outcomes of percutaneous and minimally invasive repairs of the Achilles tendon.
Flat foot due to rupture of the tibialis posterior tendon has not previously been described in children. We present three young patients who developed unilateral pes planus after old undiagnosed lacerations of the tendon. Transfer of the flexor hallucis longus to the distal stump of the tibialis posterior tendon achieved good results in all three cases. PMID:8175850
Masterson, E; Jagannathan, S; Borton, D; Stephens, M M
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
Hast, M W; Zuskov, A; Soslowsky, L J
Management of patella infera remains a difficult therapeutic endeavor. We report a case of a 21-year-old man, who had development of patella infera and knee flexion contracture after a patella fracture. Patella infera was treated by patellar tendon lengthening and augmentation with a tibialis anterior tendon allograft fixed with bioabsorbable cross-pins. The patient regained an anatomic patellar position and full range of motion at two years after surgery. PMID:24231623
Jeong, Ju Seon; Wang, Joon Ho
Bacterial contamination of tendon allografts at the completion of processing has historically been about 2 %, with tendons that are found to be culture positive being discarded. Treatment of tendon allograft with hydrogen peroxide at the beginning of tissue processing may reduce bacterial contamination, however, the potential side effects of hydrogen peroxide treatment include hydrolysis of the collagen and this may alter the mechanical properties of the graft. Pairs of human tendons were used. One was washed in 3 % hydrogen peroxide for 5 min and the untreated tendon was used as a control. The ultimate tensile strength of the tendons was determined using a material testing machine. A freeze clamp technique was used to hold the tendons securely at the high loads required to cause tendon failure. There was no statistical difference in the ultimate tensile strength between the treated and untreated tendons. Mean strength ranged from Extensor Hallucis Longus at 588 Newtons to Tibialis Posterior at 2,366 Newtons. Hydrogen peroxide washing may reduce bacterial contamination of tendon allograft and does not affect the strength of the tendon. PMID:23681552
Gardner, E M H; VonderHeide, N; Fisher, R; Brooker, G; Yates, P J
The purpose of this study was to measure the tension in the flexor digitorum profundus (FDP) tendon in zone II and the digit angle during joint manipulations that replicate rehabilitation protocols. Eight FDP tendons from eight human cadavers were used in this study. The dynamic tension in zone II of the tendon and metacarpophalangeal (MCP) joint angle were measured in various wrist and digit positions. Tension in the FDP tendon increased with MCP joint extension. There was no tension with the finger fully flexed and wrist extended (synergistic motion), but the tendon force reached 1.77 ± 0.43 N with the MCP joint hyperextended 45 degrees with the distal interphalangeal and proximal interphalangeal joints flexed. The combination of wrist extension and MCP joint hyperextension with the distal interphalangeal and proximal interphalangeal joints fully flexed, what the authors term ‘‘modified synergistic motion,’’ produced a modest tendon tension and may be a useful alternative configuration to normal synergistic motion in tendon rehabilitation.
Tanaka, Tatsuro; Amadio, Peter C.; Zhao, Chunfeng; Zobitz, Mark E.; An, Kai-Nan
Conflicts, snapping and instability of the tendons are common, and ultrasound (US) is the method of choice for evidencing these conditions thanks to the possibility to perform dynamic maneuvers during imaging studies. A conflict can occur between a tendon and a bone structure, other tendons, the retinacula or pulleys. Snapping can occur due to instability caused by rupture of the retinaculum, conflict between a thickened retinaculum and a bone prominence or due to an abnormal position of the tendon. Instability can occur due to insufficient ability of the retinaculum to keep the tendons in the bone groove or its failure to hold the tendons applied to the bone. The technique for evidencing conflicts, snapping and instability of the tendons is very demanding because it requires a thorough knowledge of the US appearance and dynamic maneuvers. However, at the present time US examination completed with dynamic maneuvers is the investigation of choice for evidencing these disorders and providing the clinicians with the necessary information.
Fantino, Olivier; Borne, J.; Bordet, Bertrand
Wrist injuries in the gymnast are due to the transformation of the upper extremity into a weight bearing entity. Gymnast wrist pain presents a difficult diagnostic and therapeutic challenge. Here, we present a new case of extensor tendon impingement in an elite gymnast. To our knowledge, there is no similar report in the literature. PMID:16253406
Wilson, S M; Dubert, T; Rozenblat, M
This study aims to verify the effects of AsGa Laser in the scarring of tendon lesion in rats with low nourishment condition and to analyze the ideal light density by means of histopathologic findings highlighted by light microscopy. After the proposed nutritional condition was verified the animals were divided into 3 groups denominated as follows: GI control group, GII laser
P. T. C. Carvalho; Cheila O. C. Batista; C. Fabíola
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
Csapo, R; Maganaris, C N; Seynnes, O R; Narici, M V
We report the clinical features, radiographic findings, management and results of a patient with a post-traumatic synovial sarcoma of the anterior tibialis tendon. Our patient was managed operatively and with radiotherapy with good clinical results. No evidence of recurrence or metastatic disease was seen at 3-year follow-up. PMID:22461273
Papapietro, Nicola; Longo, Umile Giuseppe; Palumbo, Alessio; Bianchi, Antonella; Maffuli, Nicola; Denaro, Vincenzo
Flexor tendon injuries were already treated in antiquity by Hippocrates, Galien and Avicenne. Since the Renaissance, other surgeons have attempted to repair flexor tendon injuries, but without success due to problems related to unsuitable materials and ignorance of the basic rules of asepsis and the absence of antiseptics until the second half of the 19th century. The first successful flexor tendon grafts in man were performed by K. Biesalski in 1910, E. Lexer in 1912 and L. Mayer in 1916. These three authors published their series of grafts and described in detail the anatomical, physiological and technical principles to be respected. St. Bunnell, in 1918, developed various pull-out direct suture procedures, but faced with the problems of adhesions, he abandoned this technique and proposed not to repair flexors in the digital tunnels but to graft them. He defined the famous zone which he called No man's land, which subsequently became Claude Verdan's zone II, in 1959. In 1960, C. Verdan published his first series of sutures maintained by 2 pins in zone II with comparable results to those obtained after grafting. In 1967, H. Kleinert, with his mobile suture, became the leader of direct tendon repair in zone II. 2-stage grafts were introduced in 1965 under the impetus of J. Hunter, who revised and popularized the studies conducted by A. Bassett and R.E. Caroll in 1950. PMID:9131943
The simultaneous, complete rupture of both quadriceps tendons is a rare event. Only 30 previous cases have been reported and the majority have had well-documented predisposing factors, such as chronic renal failure, gout, hyperparathyroidism, diabetes and obesity. We report a case which presented without any predisposing cause, and review the literature to date. PMID:2692688
Ribbans, W J; Angus, P D
The Achilles tendon is one of the most frequently injured tendons in humans, and yet the mechanisms underlying its injury are not well understood. This study examines the ex vivo mechanical behavior of excised human Achilles tendons to elucidate the relationships between mechanical loading and Achilles tendon injury. Eighteen tendons underwent creep testing at constant stresses from 35 to 75
Tishya A. L. Wren; Derek P. Lindsey; Gary S. Beaupré; Dennis R. Carter
The regulatory mechanisms involved in tendon homeostasis and repair are not fully understood. Accumulating data, however, demonstrate that the nervous system, in addition to afferent (sensory) functions, through efferent pathways plays an active role in regulating pain, inflammation, and tissue repair. In normal-, healing- and tendinopathic tendons three neurosignalling pathways consisting of autonomic, sensory and glutamatergic neuromediators have been established. In healthy tendons, neuromediators are found in the paratenon, whereas the proper tendon is practically devoid of nerves, reflecting that normal tendon homeostasis is regulated by pro- and anti-inflammatory mediators from the tendon surroundings. During tendon repair, however, there is extensive nerve ingrowth into the tendon proper and subsequent time-dependent appearance of sensory, autonomic and glutamatergic mediators, which amplify and fine-tune inflammation and tendon regeneration. In tendinopathy, excessive and protracted sensory and glutamatergic signalling may be involved in inflammatory, painful and hypertrophic tissue reactions. As our understanding of these processes improves, neuronal mediators may prove to be useful in the development of targeted pharmacotherapy and tissue engineering approaches to painful, degenerative and traumatic tendon disorders. PMID:24896349
Ackermann, Paul W; Franklin, Sarah L; Dean, Benjamin J F; Carr, Andrew J; Salo, Paul T; Hart, David A
PURPOSE: The purpose of this study was to establish a relationship between the lengthening of the Achilles tendon post-rupture and surgical repair to muscle activation patterns during walking in order to serve as a reference for post-surgical assessment. METHOD: The Achilles tendon lengths were collected from 4 patients with an Achilles tendon rupture 6 and 12 months post-surgery along with 5 healthy controls via ultrasound. EMG was collected from the triceps surae muscles and tibialis anterior during overground walking. RESULTS: Achilles lengths at 6 and 12 months post-surgery were significantly longer (p < 0.05) on the involved side compared to the uninvolved side, but there were no side-to-side differences in the healthy controls. The integrated EMG (iEMG) of the involved side was significantly higher than the uninvolved side in the lateral gastrocnemius at 6 months and for the medial gastrocnemius at 12 months in the patients with Achilles tendon rupture; no side-to-side difference was found in the healthy controls. The triceps surae muscles' activations were fair to moderately correlated to the Achilles lengths (0.38 < r < 0.52). CONCLUSIONS: The increased Achilles tendon length and iEMG from the triceps surae muscles indicate that loss of function is primarily caused by anatomical changes in the tendon and the appearance of muscle weakness is due to a lack of force transmission capability. This study indicates that when aiming for full return of function and strength, an important treatment goal appears to be to minimize tendon elongation. LEVEL OF EVIDENCE: Prognostic prospective case series, Level IV. PMID:23609529
Suydam, Stephen M; Buchanan, Thomas S; Manal, Kurt; Silbernagel, Karin Gravare
Fibrous extracellular matrix of tendon is considered to be an inextensible anatomical structure consisting of type I collagen fibrils arranged in parallel bundles. Under polarized light microscopy the collagen fibre bundles appear crimped with alternating dark and light transverse bands. This study describes the ultrastructure of the collagen fibrils in crimps of both relaxed and in vivo stretched rat Achilles tendon. Under polarized light microscopy crimps of relaxed Achilles tendons appear as isosceles or scalene triangles of different size. Tendon crimps observed via SEM and TEM show the single collagen fibrils that suddenly change their direction containing knots. The fibrils appear partially squeezed in the knots, bent on the same plane like bayonets, or twisted and bent. Moreover some of them lose their D-period, revealing their microfibrillar component. These particular aspects of collagen fibrils inside each tendon crimp have been termed 'fibrillar crimps' and may fulfil the same functional role. When tendon is physiologically stretched in vivo the tendon crimps decrease in number (46.7%) (P<0.01) and appear more flattened with an increase in the crimp top angle (165 degrees in stretched tendons vs. 148 degrees in relaxed tendons, P<0.005). Under SEM and TEM, the 'fibrillar crimps' are still present, never losing their structural identity in straightened collagen fibril bundles of stretched tendons even where tendon crimps are not detectable. These data suggest that the 'fibrillar crimp' may be the true structural component of the tendon crimp acting as a shock absorber during physiological stretching of Achilles tendon. PMID:17229278
Franchi, Marco; Fini, Milena; Quaranta, Marilisa; De Pasquale, Viviana; Raspanti, Mario; Giavaresi, Gianluca; Ottani, Vittoria; Ruggeri, Alessandro
We hypothesized that the transplantation of Scx-transduced tendon-derived stem cells (TDSCs) promoted better tendon repair compared to the transplantation of mock-transduced cells. This study thus aimed to investigate the effect of Scx transduction on the expression of lineage markers in TDSCs and the effect of the resulting cell line in the promotion of tendon repair. Rat non-GFP or GFP-TDSCs were transduced with Scx or empty lentiviral vector (Mock) and selected by blasticidin. The mRNA expressions of Scx and different lineage markers were examined by qRT-PCR. The effect of the transplantation of GFP-TDSC-Scx on tendon repair was then tested in a rat unilateral patellar tendon window injury model. The transplantation of GFP-TDSC-Mock and scaffold-only served as controls. At week 2, 4 and 8 post-transplantation, the repaired patellar tendon was harvested for ex vivo fluorescent imaging, vivaCT imaging, histology, immunohistochemistry and biomechanical test. GFP-TDSC-Scx consistently showed higher expressions of most of tendon- and cartilage- related markers compared to the GFP-TDSC-Mock. However, the effect of Scx transduction on the expressions of bone-related markers was inconclusive. The transplanted GFP-TDSCs could be detected in the window wound at week 2 but not at week 4. Ectopic mineralization was detected in some samples at week 8 but there was no difference among different groups. The GFP-TDSC-Scx group only statistically significantly improved tendon repair histologically and biomechanically compared to the Scaffold-only group and the GFP-TDSC-Mock group at the early stage of tendon repair. There was significant higher expression of collagen type I in the window wound in the GFP-TDSC-Scx group compared to the other two groups at week 2. The transplantation of GFP-TDSC-Scx promoted healing at the early stage of tendon repair in a rat patellar tendon window injury model.
Lee, Yuk Wa; Wong, Yin Mei
The aim of this study was to investigate the association between foot type and the morphometry of selected muscles and tendons of the lower limb. Sixty-one healthy participants (31 male, 30 female; aged 27.1?±?8.8 years) underwent gray-scale musculoskeletal ultrasound examination to determine the anterior-posterior (AP) thickness of tibialis anterior, tibialis posterior, and peroneus longus muscles and tendons as well as the Achilles tendon. Foot type was classified based on arch height and footprint measurements. Potentially confounding variables (height, weight, hip and waist circumference, rearfoot and ankle joint range of motion, and levels of physical activity) were also measured. Multiple linear regression models were used to determine the association between foot type with muscle and tendon morphometry accounting for potentially confounding variables. Foot type was significantly and independently associated with AP thickness of the tibialis anterior tendon, peroneus longus muscle, and Achilles tendon, accounting for approximately 7% to 16% of the variation. Flat-arched feet were associated with a thicker tibialis anterior tendon, a thicker peroneus longus muscle, and a thinner Achilles tendon. Foot type is associated with morphometry of tendons that control sagittal plane motion of the rearfoot; and the peroneus longus muscle that controls frontal plane motion of the rearfoot. These findings may be related to differences in tendon loading during gait. PMID:23301865
Murley, G S; Tan, J M; Edwards, R M; De Luca, J; Munteanu, S E; Cook, J L
Background Among the various complications described in literature, the patellar tendon ossification is an uncommon occurrence in anterior cruciate ligament (ACL) reconstruction using bone – patellar tendon – bone graft (BPTB). The heterotopic ossification is linked to knee traumatism, intramedullary nailing of the tibia and after partial patellectomy, but only two cases of this event linked to ACL surgery have been reported in literature. Case presentation We present a case of a 42-year-old Caucasian man affected by symptomatic extended heterotopic ossification of patellar tendon after 20 months from ACL reconstruction using BPTB. The clinical diagnosis was confirmed by Ultrasound, X-Ray and Computed Tomography studies, blood tests were performed to exclude metabolic diseases then the surgical removal of the lesion was performed. After three years from surgery, the patient did not report femoro-patellar pain, there was not range of motion limitation and the clinical-radiological examinations resulted negative. Conclusion The surgical removal of the ossifications followed by anti-inflammatory therapy, seems to be useful in order to relieve pain and to prevent relapses. Moreover, a thorough cleaning of the patellar tendon may reveal useful, in order to prevent bone fragments remain inside it and to reduce patellar tendon heterotopic ossification risk.
46 fingers in 42 patients undergoing 2-stage flexor tendon grafting for traumatic injury in zone 2 were evaluated with an average follow up of 13 months (range 6 to 120 months). 24 anastomoses between FDS and FDP were performed according to the Paneva Holevitch procedure. In all other cases, palmaris longus or plantaris were used as tendon grafts during the second stage. Proximal fixation was always performed in the palm. 3 or more pulleys were reconstructed in all cases. In 21 cases, pulley reconstruction required the use of excised tendon remnants or retina-culum dorsalis. Distal fixation was performed to the distal phalanx in 42 cases and to the second phalanx in 4 cases, during the second stage. Overall, 85% patients obtained a good or fair result in terms of TAM (total active motion) with
Alnot, J Y; Mouton, P; Bisson, P
Ossification of the Achilles tendon is a rare condition. We recently treated a patient with ossification of bilateral Achilles tendons. The patient was a 50 year old male whose chief complaint was discomfort around the Achilles tendon. He had a previous history of treatment of bilateral club feet. On the roentgenograms, the length of the bony mass in the Achilles tendon was 5.5 cm on the right side and 1.5 cm on the left side. The left side was treated by surgical removal of a bony mass and suture of the tendon. Microscopic examination of the extirpated specimen revealed bone formation through enchondral and intramembranous ossification in the Achilles tendon. PMID:7981796
Hatori, M; Kita, A; Hashimoto, Y; Watanabe, N; Sakurai, M
Mathematical and computational modeling is in demand to help address current challenges in mechanobiology of musculoskeletal tissues. In particular for tendon, the high clinical importance of the tissue, the huge mechanical demands placed on it and its ability to adapt to these demands, require coupled, multiscale models incorporating complex geometrical and microstructural information as well as time-based descriptions of cellular activity and response.This review introduces the information sources required to develop such multiscale models. It covers tissue structure and biomechanics, cell biomechanics, the current understanding of tendon's ability in health and disease to update its properties and structure and the few already existing multiscale mechanobiological models of the tissue. Finally, a sketch is provided of what such models could achieve ideally, pointing out where experimental data and knowledge are still missing. PMID:23681792
Thompson, Mark S
It is well known that rupture of the flexor hallucis longus tendon can be associated with open injuries and that closed rupture of the flexor hallucis longus tendon is rare. Tendon injuries of the foot can occur secondary to direct, indirect, or repetitive injury. Repetitive tendon injuries can cause tendinitis or stenosing tenosynovitis. Tendinitis is associated with internal tendon injury that can present with tendon thickening, mucinoid degeneration, nodule development, or in situ partial tears. Stenosing tenosynovitis is the development of tendon adhesions within the tendon sheath that interfere with tendon gliding, known as trigger toe. The flexor hallucis longus tendon is susceptible to injury along its entire course. A total of 35 cases of complete or partial closed ruptures of the flexor hallucis longus tendon have been reported. We present the case of complete subcutaneous rupture of the flexor hallucis longus tendon associated with trauma at the proximal phalangeal head. PMID:22153296
Noda, Daisuke; Yoshimura, Ichiro; Kanazawa, Kazuki; Hagio, Tomonobu; Naito, Masatoshi
\\u000a Stark first described distal biceps tendon rupture in 1843.1 The earliest reports of surgical repair was in 1897 by Johnson and later in 1898 by Acquaviva.1, 2 Fischer and Shepanek in 19563 and Meherin and Kilgore in 19604 reported on a single incision for reattachment of the biceps to the radial tuberosity. This was shown to significantly improve\\u000a flexion and
Jason A. Schneider; Peter D. McCann
The technique of arthroscopic subscapularis repair continues to evolve. A three-sided subscapularis release (e.g. anterior, posterior, superior) is commonly advocated for improving tendon excursion to bone. However, a lateral release is commonly required as well, particularly for full thickness, upper subscapularis tears and full thickness, complete subscapularis tears. We describe the techniques to identify and release the lateral subscapularis border, which aids in the completion of other releases.
Lo, Ian K.Y.; Nelson, Atiba A.; Burkhart, Stephen S
Atypical tuberculous tenosynovitis of the foot and ankle is extremely rare. The determination of the Mycobacterium species is essential because resistance of atypical mycobacterial strains to antituberculous drugs is often encountered. We report a case of Mycobacterium chelonae paratendinous and intratendinous infection involving the Achilles tendon. Repeat aggressive irrigation and debridement procedures, coupled with removal of foreign materials and the appropriate use of prolonged antibiotic therapy, can result in a successful long-term outcome. PMID:24529751
Lui, Tun Hing; Chan, Kwok Bill
We present a case of quadriceps tendon (QT) rupture. QT ruptures can occur in all ages. The cause is mostly traumatic in origin. Spontaneous ruptures that are thought to result from predisposing conditions are rare. Post-convulsion QT ruptures lacking traumas in their history can be overlooked in clinical examinations. This should be born in mind by the attending physician, as early diagnosis and treatment of the condition can lead to satisfactory outcomes.
Erkut, Adem; Guvercin, Yilmaz; Sahin, Rifat; Keskin, Davut
Eighteen patients with 20 symptomatic hips underwent lengthening of the iliopsoas tendon for persistent painful snapping of this "internal" variety of snapping hip. We referred to the pathologic, painful snapping of the iliopsoas in the deep anterior groin as the "internal" snapping hip. This is in contrast to the more common and better-known "external" snapping that involves the greater trochanter and its overlying soft tissues. The results of our iliopsoas lengthening procedure are presented here. Lengthening of the iliopsoas tendon was accomplished by step cutting of the tendinous portion of the iliopsoas. The pathoanatomy of this poorly understood symptom complex was described in 1984 paper from this institution and is reviewed here. Iliopsoas bursography demonstrated a sudden jerking movement of the iliopsoas tendon between the anterior inferior iliac spine and iliopectineal eminence, synchronous with the patient's pain and often accompanied by an audible snap. The average preoperative duration of symptoms was 2.9 years, and the average length of postoperative followup was 25 months. All patients, except one, had a marked reduction in the frequency of snapping after tendon lengthening, and 14 of 20 hips had no snapping postoperatively. Of the six patients who had recurrence of snapping, all but one stated that this occurred much less frequently and was much less painful compared to the preoperative state. Two hips required reoperation. Postoperatively, only three patients complained of subjective weakness, and most patients were unlimited in physical activity with return to activities such as competitive football, pole vaulting, and long-distance running.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2252086
Jacobson, T; Allen, W C
We present a case of a closed rupture of the flexor digitorum profundus tendon of the small finger. It is our hypothesis that because of pisotriquetral instability as a result of a lesion of the pisotriquetral ligaments the flexor digitorum profundus tendon was entrapped repeatedly between the pisiform and triquetrum. This resulted in an attritional lesion of the tendon. The pisotriquetral joint showed no bone abnormalities. PMID:15043895
Corten, Eveline M L; van den Broecke, Duco G; Kon, Moshe; Schuurman, Arnold H
. The purpose of this study was to investigate the differences in the viscoelastic properties of human tendon structures (tendon\\u000a and aponeurosis) in the medial gastrocnemius muscle between men (n=16) and women (n=13). The elongation of the tendon and aponeurosis of the medial gastrocnemius muscle was measured directly by ultrasonography,\\u000a while the subjects performed ramp isometric plantar flexion up to
Keitaro Kubo; Hiroaki Kanehisa; Tetsuo Fukunaga
A coupling mechanism that can permanently fix a forcefully contracting muscle to a bone anchor or any totally inert prosthesis would meet a serious need in orthopaedics. Our group developed the OrthoCoupler™ device to satisfy these demands. The objective of this study was to test OrthoCoupler’s performance in vitro and in vivo in the goat semitendinosus tendon model. For in vitro evaluation, 40 samples were fatigue-tested, cycling at 10 load levels, n=4 each. For in vivo evaluation, the semitendinosus tendon was removed bilaterally in 8 goats. Left sides were reattached with an OrthoCoupler, and right sides were reattached using the Krackow stitch with #5 braided polyester sutures. Specimens were harvested 60 days post-surgery and assigned for biomechanics and histology. Fatigue strength of the devices in vitro was several times the contractile force of the semitendinosus muscle. The in vivo devices were built equivalent to two of the in vitro devices, providing an additional safety factor. In strength testing at necropsy, suture controls pulled out at 120.5 ± 68.3 N, whereas each OrthoCoupler was still holding after the muscle tore, remotely, at 298±111.3N (mean ± SD)(p<0.0003). Muscle tear strength was reached with the fiber-muscle composite produced in healing still soundly intact. This technology may be of value for orthopaedic challenges in oncology, revision arthroplasty, tendon transfer, and sports-injury reconstruction.
Melvin, Alan; Litsky, Alan; Mayerson, Joel; Witte, David; Melvin, David; Juncosa-Melvin, Natalia
This study aims to verify the effects of AsGa Laser in the scarring of tendon lesion in rats with low nourishment condition and to analyze the ideal light density by means of histopathologic findings highlighted by light microscopy. After the proposed nutritional condition was verified the animals were divided into 3 groups denominated as follows: GI control group, GII laser 1 J/sq.cm. and GIII laser 4 J/sq.cm. The lesions were induced by means of routine surgical process for tendon exposure: There was a crushing process with Allis pincers followed by saturated incision. The data obtained in relation to the amount of macrophage, leukocyte, fibroblast, vessel neoformation, fibrosis and collagen were submitted to parametric statistic procedures of variance analysis and "Tukey" Test and the result obtained was p < 0,05. According to the obtained results it can be concluded that low power laser therapy proved to be efficient in tendon repairing even though the animals suffered from malnutrition as well as the 1 J energy density proved to be more efficient in this case.
Carvalho, P. T. C.; Batista, Cheila O. C.; Fabíola, C.
Surgical reattachment of tendon and bone such as in rotator cuff repair, patellar-patella tendon repair and anterior cruciate ligament (ACL) reconstruction often fails due to the failure of regeneration of the specialized tissue ("enthesis") which connects tendon to bone. Tendon-to-bone healing taking place between inhomogenous tissues is a slow process compared to healing within homogenous tissue, such as tendon to tendon or bone to bone healing. Therefore special attention must be paid to augment tendon to bone insertion (TBI) healing. Apart from surgical fixation, biological and biophysical interventions have been studied aiming at regeneration of TBI healing complex, especially the regeneration of interpositioned fibrocartilage and new bone at the healing junction. This paper described the biology and the factors influencing TBI healing using patella-patellar tendon (PPT) healing and tendon graft to bone tunnel healing in ACL reconstruction as examples. Recent development in the improvement of TBI healing and directions for future studies were also reviewed and discussed.
With recent advances in multidetector computed tomography (MDCT) acquisition and reconstruction options, MDCT can now be used successfully for evaluating tendon abnormalities. In this article, MDCT protocol optimization for the imaging of tendons is underscored, and applications of MDCT for assessing tendon pathology are highlighted. Although our retrospective experience of CT imaging with 2-dimensional multiplanar reconstructions and 3-dimensional postprocessing techniques is reviewed, potential applications for newer CT technologies, including dual-energy CT and 4-dimensional CT imaging of the peripheral tendons, are also discussed. PMID:24625602
Demehri, Shadpour; Chalian, Majid; Farahani, Sahar J; Fishman, Elliot K; Fayad, Laura M
We report a rare case of subcutaneous peroneus longus tendon rupture associated with os peroneum fracture. Three dimensional computed tomographic scan was useful to understand this disorder. We treated the patient with excision of fractured os peroneum and tenodesis of the proximal stump of the ruptured peroneus longus tendon to the lateral aspect of the calcaneus. Key points In order to understand a rare case of subcutaneous peroneus longus tendon rupture associated with os peroneum fracture, three dimensional computed tomographic scan was useful. The patient was treated with excision of fractured os peroneum and tenodesis of the proximal stump of the ruptured peroneus longus tendon to the lateral aspect of the calcaneus.
Fujioka, Hiroyuki; Kokubu, Takeshi; Makino, Takeshi; Nagura, Issei; Maeda, Toshihisa; Kurosaka, Masahiro; Okuno, Hiroaki; Yamagiwa, Tokuyoshi; Tanaka, Juichi; Yoshiya, Shinichi
Tendons are collagen-rich structures that link muscle to cartilage. By using quail-chick chimeras, it has been shown that tendon and cartilage cells originate from the same mesodermic compartment, which is distinct from that giving rise to muscle cells. Axial tendons originate from the sclerotomal compartment, and limb tendons originate from the lateral plate, whereas axial and limb muscles derive from dermomyotomes. Despite these different embryologic origins, muscle and tendon morphogenesis occurs in close spatial and temporal association. Facilitated by the distinct embryologic origin of myogenic and tendon cells, surgical studies in the avian embryo have highlighted interactions between tendons and muscles, during embryonic development. However, these interactions seem to differ between axial and limb levels. The molecular mechanisms underlying muscle and tendon interactions have been shown recently to involve different members of the fibroblast growth factor family. This review covers the available data on the early steps of tendon formation in the limb and along the primary axis. The relationship with muscle morphogenesis will be highlighted. PMID:14991700
Edom-Vovard, Frédérique; Duprez, Delphine
Tendon adhesions are one of the most concerning complications after surgical repair of flexor tendon injury. Extracellular signal-regulated kinase (ERK) 2 plays crucial roles in fibroblast proliferation and collagen expression which contributes to the formation of tendon adhesions after flexor tendon surgery. Using a chicken model, we have examined the effects of a small interfering RNA (siRNA) targeting ERK2 delivered by a lentiviral system on tendon adhesion formation with an adhesion scoring system, histological assessment, and biomechanical evaluation. It was found that ERK2 siRNA effectively suppressed the increase of fibroblasts and the formation of tendon adhesions (p < 0.05 compared with the control group). Moreover, no statistically significant reduction in breaking force was detected between the ERK2 siRNA group and the control group. These results show that the lentiviral-mediated siRNA system is effective in preventing tendon adhesion formation but not to tendon healing, and may be used for tendon repair after confirmation and improvement by future detailed studies.
Ruan, Hongjiang; Liu, Shen; Li, Fengfeng; Li, Xujun; Fan, Cunyi
Patients undergoing surgery for posterior tibial tendon dysfunction may require tendon transfer. The flexor digitorum longus is most commonly transferred, although the flexor hallucis longus and peroneus brevis have also been described in the literature. This article discusses the advantages and disadvantages of the different tendons, the surgical techniques used to perform them, and their results in the literature, concentrating principally on studies in which additional bone procedures were not performed. This article will also discuss the potential role for isolated soft tissue procedures in the treatment of stage 2 posterior tibial tendon dysfunction. PMID:22541521
Aronow, Michael S
The purpose of this study was to examine patellar tendon (PT) size and mechanical properties in subjects with a side-to-side strength difference of > or =15% due to sport-induced loading. Seven elite fencers and badminton players were included. Cross-sectional area (CSA) of the PT obtained from MRI and ultrasonography-based measurement of tibial and patellar movement together with PT force during isometric contractions were used to estimate mechanical properties of the PT bilaterally. We found that distal tendon and PT, but not mid-tendon, CSA were greater on the lead extremity compared with the nonlead extremity (distal: 139 +/- 11 vs. 116 +/- 7 mm(2); mid-tendon: 85 +/- 5 vs. 77 +/- 3 mm(2); proximal: 106 +/- 7 vs. 83 +/- 4 mm(2); P < 0.05). Distal tendon CSA was greater than proximal and mid-tendon CSA on both the lead and nonlead extremity (P < 0.05). For a given common force, stress was lower on the lead extremity (52.9 +/- 4.8 MPa) compared with the nonlead extremity (66.0 +/- 8.0 MPa; P < 0.05). PT stiffness was also higher in the lead extremity (4,766 +/- 716 N/mm) compared with the nonlead extremity (3,494 +/- 446 N/mm) (P < 0.05), whereas the modulus did not differ (lead 2.27 +/- 0.27 GPa vs. nonlead 2.16 +/- 0.28 GPa) at a common force. These data show that a habitual loading is associated with a significant increase in PT size and mechanical properties. PMID:18556433
Couppé, C; Kongsgaard, M; Aagaard, P; Hansen, P; Bojsen-Moller, J; Kjaer, M; Magnusson, S P
Pentadecapeptide BPC 157, composed of 15 amino acids, is a partial sequence of body protection compound (BPC) that is discovered in and isolated from human gastric juice. Experimentally it has been demonstrated to accelerate the healing of many different wounds, including transected rat Achilles tendon. This study was designed to investigate the potential mechanism of BPC 157 to enhance healing of injured tendon. The outgrowth of tendon fibroblasts from tendon explants cultured with or without BPC 157 was examined. Results showed that BPC 157 significantly accelerated the outgrowth of tendon explants. Cell proliferation of cultured tendon fibroblasts derived from rat Achilles tendon was not directly affected by BPC 157 as evaluated by MTT assay. However, the survival of BPC 157-treated cells was significantly increased under the H(2)O(2) stress. BPC 157 markedly increased the in vitro migration of tendon fibroblasts in a dose-dependent manner as revealed by transwell filter migration assay. BPC 157 also dose dependently accelerated the spreading of tendon fibroblasts on culture dishes. The F-actin formation as detected by FITC-phalloidin staining was induced in BPC 157-treated fibroblasts. The protein expression and activation of FAK and paxillin were determined by Western blot analysis, and the phosphorylation levels of both FAK and paxillin were dose dependently increased by BPC 157 while the total amounts of protein was unaltered. In conclusion, BPC 157 promotes the ex vivo outgrowth of tendon fibroblasts from tendon explants, cell survival under stress, and the in vitro migration of tendon fibroblasts, which is likely mediated by the activation of the FAK-paxillin pathway. PMID:21030672
Chang, Chung-Hsun; Tsai, Wen-Chung; Lin, Miao-Sui; Hsu, Ya-Hui; Pang, Jong-Hwei Su
The formation of the musculoskeletal system represents an intricate process of tissue assembly involving heterotypic inductive interactions between tendons, muscles and cartilage. An essential component of all musculoskeletal systems is the anchoring of the force-generating muscles to the solid support of the organism: the skeleton in vertebrates and the exoskeleton in invertebrates. Here, we discuss recent findings that illuminate musculoskeletal assembly in the vertebrate embryo, findings that emphasize the reciprocal interactions between the forming tendons, muscle and cartilage tissues. We also compare these events with those of the corresponding system in the Drosophila embryo, highlighting distinct and common pathways that promote efficient locomotion while preserving the form of the organism.
Schweitzer, Ronen; Zelzer, Elazar; Volk, Talila
Sixteen patients underwent detailed arthroscopic evaluation; all had moderate to severe, primarily unexplained shoulder pain provoked by anterior elevation and internal rotation, and all were nonresponsive to subacromial injection of local anesthetic. None of the patients had any symptoms or signs of instability. Partial subscapularis lesions were documented in 10 of 13 patients who had undergone preoperative arthro-magnetic resonance imaging. At arthroscopy, an isolated lesion of the common humeral insertion of the superior glenohumeral and coracohumeral ligaments (a so-called pulley lesion) was found in 3 cases, a lesion associating a pulley and an articular side partial subscapularis lesion in 10 cases, and an isolated articular side partial subscapularis tear in 3 cases. The most painful movement, which consisted of flexion and internal rotation, caused impingement of the involved ligamentous and/or capsular insertions in all patients. If the arm was elevated above 90 degrees, the zone of mechanical contact was between the long head of the biceps and the pulley region and superiormost aspect of the labrum; if elevation was decreased, impingement occurred between the tendinous insertion of the subscapularis and the anterior glenoid labrum and rim. This study suggests that in addition to the posterosuperior impingement of the supraspinatus tendon originally described by Walch, anterosuperior impingement of the deep surface of the subscapularis is a form of intraarticular impingement responsible for painful structural disease of the shoulder. PMID:11155300
Gerber, C; Sebesta, A
Arthroscopic suprapectoral techniques for tenodesis of the long head of the biceps tendon (LHB) are appropriate for the treatment of proximal biceps lesions. Several types of techniques and fixation devices have been described and evaluated in biomechanical studies regarding primary stability. In this technical note, we describe an all-arthroscopic suprapectoral technique using the 6.25-mm Bio-SwiveLock device (Arthrex, Naples, FL) for an interference screw–like bony fixation after having armed the tendon with a lasso-loop stitch. Both the interference screw fixation and securing of the lasso-loop tendon have been well described and approved in biomechanical tests concerning the primary stability. One advantage of this technique performed from the glenohumeral space, in addition to the strong and secure fixation with ingrowth of the tendon in a bony canal, is the avoidance of touching the soft tissue above the bicipital groove, which results in a smooth fitting of the tendon into its natural canal and therefore avoids mechanical irritation of the stump at the rotator interval. In conclusion, the all-arthroscopic suprapectoral LHB tenodesis performed from the glenohumeral space with the modified lasso-loop stitch for securing of the tendon and the 6.25-mm Bio-SwiveLock suture anchor for interference screw–like bony tendon fixation is an appropriate technique for the treatment of LHB-associated lesions.
Patzer, Thilo; Kircher, Jorn; Krauspe, Ruediger
The deep tendon reflex (DTR) is often utilized to characterize the neuromuscular health of individuals because it is cheap, quick to implement, and requires limited equipment. However, DTR assessment is unreliable and assessor-dependent improve the reliability of the DTR assessment, we devised a novel standardization procedure. Our approach is based on the hypothesis that the neuromuscular state of a muscle changes systematically with respect to the indentation depth of its tendon. We tested the hypothesis by progressively indenting the biceps tendons on each side of nine hemiplegic stroke survivors to different depths, and then superimposing a series of brief controlled taps at each indentation depth to elicit a reflex response. Our results show that there exists a unique indentation depth at which reflex responses are consistently recorded (termed the Reflex Threshold) with increasing amplitude along increasing indentation depth. We further show that the reflex threshold depth is systematically smaller on the affected side of stroke survivors and that it is negatively correlated with the Modified Ashworth Score (VAF 70%). Our procedure also enables measurement of passive mechanical properties at the indentation location. In conclusion, our study shows that controlling for the indentation depth of the tendon of a muscle alters its reflex response predictably. Our novel device and method could be used to estimate neuromuscular changes in muscle (e.g., spasticity). Although some refinement is needed, this method opens the door to more reliable quantification of the DTR. PMID:24621852
Chardon, Matthieu K; Rymer, W Zev; Suresh, Nina L
Scleraxis is a bHLH transcription factor that plays a central role in promoting fibroblast proliferation and matrix synthesis during the embryonic development of tendons. Mice with a targeted inactivation of scleraxis (Scx?/?) fail to properly form limb tendons, but the role that scleraxis has in regulating the growth and adaptation of tendons of adult organisms is unknown. To determine if scleraxis expression changes in response to a physiological growth stimulus to tendons, we subjected adult mice that express GFP under the control of the scleraxis promoter (ScxGFP) to a six week treadmill training program designed to induce adaptive growth in Achilles tendons. Age matched sedentary ScxGFP mice were used as controls. Scleraxis expression was sparsely observed in the epitenon region of sedentary mice, but in response to treadmill training, scleraxis was robustly expressed in fibroblasts that appeared to be emerging from the epitenon and migrating into the superficial regions of tendon fascicles. Treadmill training also led to an increase in scleraxis, tenomodulin, and type I collagen gene expression as measured by qPCR. These results suggest that in addition to regulating the embryonic formation of limb tendons, scleraxis also appears to play an important role in the adaptation of adult tendons to physiological loading.
Mendias, Christopher L; Gumucio, Jonathan P; Bakhurin, Konstantin I; Lynch, Evan B; Brooks, Susan V
The standard post-mortem storage method for biomechanical testing is freezing. Freezing minimally alters the biomechanical characteristics of tendons but only suspends the process of decay. Chemical fixation arrests decay and overcomes risk of infection, but alters the biomechanical properties of tendons. On the other hand, Thiel preservation has been reported to maintain soft tissue consistency similar to that of living tissue. The current study investigates the effects of Thiel embalming on human digitorum profundus tendons (FDP) from fresh-frozen and Thiel embalmed cadavers. Cross-sectional area was measured at pre-load, samples were preconditioned and then ramped at a constant strain-rate to failure. Thiel preserved tendons had statistically lower failure stress with median of 38MPa compared to fresh frozen samples with median of 60MPa (p-value=0.048) and trended to a decreased tangential modulus. To overcome limited donor number and masking factors of age, gender, and time embalmed, we also performed experiments in rat tail tendon fascicle. Similar quasi-static ramp to failure tests were performed with control and Thiel treated sample pairs. Similar differences were observed to those found as in human FDP, however these trends were statistically significant. In both tendons, Thiel preserved samples demonstrated altered failure characteristics, indicating a different collagen fiber/collagen network failure mechanism most likely due to partial denaturing by boric acid in Thiel solution. In conclusion, Thiel embalmed tendons did not faithfully represent the biomechanical characteristics of fresh frozen tendons. PMID:21511447
Fessel, Gion; Frey, Kevin; Schweizer, Andreas; Calcagni, Maurizio; Ullrich, Oliver; Snedeker, Jess G
An important function of skeletal muscle is deceleration via active muscle fascicle lengthening, which dissipates movement energy. The mechanical interplay between muscle contraction and tendon elasticity is critical when muscles produce energy. However, the role of tendon elasticity during muscular energy dissipation remains unknown. We tested the hypothesis that tendon elasticity functions as a mechanical buffer, preventing high (and probably damaging) velocities and powers during active muscle fascicle lengthening. We directly measured lateral gastrocnemius muscle force and length in wild turkeys during controlled landings requiring rapid energy dissipation. Muscle-tendon unit (MTU) strain was measured via video kinematics, independent of muscle fascicle strain (measured via sonomicrometry). We found that rapid MTU lengthening immediately following impact involved little or no muscle fascicle lengthening. Therefore, joint flexion had to be accommodated by tendon stretch. After the early contact period, muscle fascicles lengthened and absorbed energy. This late lengthening occurred after most of the joint flexion, and was thus mainly driven by tendon recoil. Temporary tendon energy storage led to a significant reduction in muscle fascicle lengthening velocity and the rate of energy absorption. We conclude that tendons function as power attenuators that probably protect muscles against damage from rapid and forceful lengthening during energy dissipation.
Konow, Nicolai; Azizi, Emanuel; Roberts, Thomas J.
Posterior tibial tendon dysfunction is common and a major cause of flat foot (pes planus) and functional impairment in adults. It is frequently undiagnosed and therefore inappropriately managed. This review raises awareness of posterior tibial tendon dysfunction with the intention of improving patient management. PMID:22875521
Singh, Rahul; King, Amanda; Perera, Anthony
Achilles tendinopathy is a common disorder and is more prevalent in men. Although differences in tendon mechanics between men and women have been reported, understanding of tendon mechanics in young active people is limited. Moreover, there is limited understanding of changes in tendon mechanics in response to acute exercise. Our purpose was to compare Achilles tendon mechanics in active young adult men and women at rest and after light and strenuous activity in the form of repeated jumping with an added load. Participants consisted of 17 men and 14 women (18-30 years) who were classified as being at least moderately physically active as defined by the International Physical Activity Questionnaire. Tendon force/elongation measures were obtained during an isometric plantarflexion contraction on an isokinetic dynamometer with simultaneous ultrasound imaging of the Achilles tendon approximate to the soleus myotendinous junction. Data were collected at rest, after a 10-minute treadmill walk, and after a fatigue protocol of 100 toe jumps performed in a Smith machine, with a load equaling 20% of body mass. We found greater tendon elongation, decreased stiffness, and lower Young's modulus only in women after the jumping exercise. Force and stress were not different between groups but decreased subsequent to the jumping exercise bout. In general, women had greater elongation and strain, less stiffness, and a lower Young's modulus during plantarflexor contraction. These data demonstrate differences in tendon mechanics between men and women and suggest a potential protective mechanism explaining the lower incidence of Achilles tendinopathy in women. PMID:24552794
Joseph, Michael F; Lillie, Kurtis R; Bergeron, Daniel J; Cota, Kevin C; Yoon, Joseph S; Kraemer, William J; Denegar, Craig R
The authors describe a new radiographic sign of rupture of the Achilles tendon system. It is a fracture, with separation through an osteophyte at the insertion of this tendon. Previously reported signs are also discussed as well as the present case report.
Newmark, H.; Mellon, W.S. Jr.; Malhotra, A.K.; Olken, S.M.; Halls, J.
An important function of skeletal muscle is deceleration via active muscle fascicle lengthening, which dissipates movement energy. The mechanical interplay between muscle contraction and tendon elasticity is critical when muscles produce energy. However, the role of tendon elasticity during muscular energy dissipation remains unknown. We tested the hypothesis that tendon elasticity functions as a mechanical buffer, preventing high (and probably damaging) velocities and powers during active muscle fascicle lengthening. We directly measured lateral gastrocnemius muscle force and length in wild turkeys during controlled landings requiring rapid energy dissipation. Muscle-tendon unit (MTU) strain was measured via video kinematics, independent of muscle fascicle strain (measured via sonomicrometry). We found that rapid MTU lengthening immediately following impact involved little or no muscle fascicle lengthening. Therefore, joint flexion had to be accommodated by tendon stretch. After the early contact period, muscle fascicles lengthened and absorbed energy. This late lengthening occurred after most of the joint flexion, and was thus mainly driven by tendon recoil. Temporary tendon energy storage led to a significant reduction in muscle fascicle lengthening velocity and the rate of energy absorption. We conclude that tendons function as power attenuators that probably protect muscles against damage from rapid and forceful lengthening during energy dissipation. PMID:21957134
Konow, Nicolai; Azizi, Emanuel; Roberts, Thomas J
A musculoskeletal model of the hand is needed to investigate the pathomechanics of tendon-related disorders and carpal tunnel syndrome. The purpose of this thesis was to develop a model with realistic extrinsic finger flexor tendon excursions and moment arms. An existing upper extremity model served as a starting point, which had programmed movement for the index finger. Movement capabilities were
Aaron Michael Joseph Kociolek
A Clinical Decision Support System has been developed using the Exsys software for the flexor tendon injuries in Zone II encompassing the continuum from injury to complete rehabilitation of the tendon. The system architecture uses the rules based logic blocks to create a decision support system, which takes the user through series of questions, and based on the answers input,
Prashant Junankar; Dinesh P. Mital; Syed Haque; Shankar Srinivasan
The presence of tendon xanthomas is an almost certain indicator of familial hypercholesterolemia (FH). They also reflect coronary atherosclerotic burden and therefore must be treated aggressively. Tendon xanthomas also occur in two rare conditions, cerebrotendinous xanthomatosis and sitosterolemia, which are not easily confused with FH, can be easily differentiated with clinical history and biochemical tests. PMID:23993019
Patil, Shivanand; Kharge, Jayashree; Bagi, Vittal; Ramalingam, Rangaraj
The presence of tendon xanthomas is an almost certain indicator of familial hypercholesterolemia (FH). They also reflect coronary atherosclerotic burden and therefore must be treated aggressively. Tendon xanthomas also occur in two rare conditions, cerebrotendinous xanthomatosis and sitosterolemia, which are not easily confused with FH, can be easily differentiated with clinical history and biochemical tests.
Patil, Shivanand; Kharge, Jayashree; Bagi, Vittal; Ramalingam, Rangaraj
The purpose of this article is to update the orthopedic community on the planning and implementation of tendon transfers in the foot and ankle. This information will serve to reinforce those principles and factors that are inherent in successful performance of tendon transfer. In addition, the authors highlight recent updates that impact decision-making for these procedures. PMID:24548506
Dowd, Thomas; Bluman, Eric M
ObjectivesExtensor hallucis longus (EHL) tendon injuries can occur in taekwondo athletes when performing hyperplantarflexed barefoot kicking exercises. A state of full excursion of the extensor tendon is used to strike opponents in which the metatarsal bone and the proximal phalanx area is in contact with the opponent. The purpose of this study is to examine the incidence of extensor hallucis
Kyung Tai Lee; Yun Sun Choi; Young Koo Lee; Jeong Pil Lee; Ki Won Young; Shin Yi Park
Chronic tendon pathology is a common and often disabling condition, the causes of which remain poorly understood. The continuum model of tendon pathology was proposed to provide a model for the staging of tendon pathology and to assist clinicians in managing this often complex condition (Br. J. Sports Med., 43, 2009, 409). The model presents clinical, histological and imaging evidence for the progression of tendon pathology as a three-stage continuum: reactive tendinopathy, tendon disrepair and degenerative tendinopathy. It also provides clinical information to assist in identifying the stage of pathology, in addition to proposed treatment approaches for each stage. The usefulness of such a model is determined by its ability to incorporate and inform new and emerging research. This review examines the degree to which recent research supports or refutes the continuum model and proposes future directions for clinical and research application of the model.
McCreesh, Karen; Lewis, Jeremy
We present an unusual case of an athletic 17-year-old male cyclist with bilateral chronic dislocating biceps femoris tendons. On flexion of the knee, the biceps tendon subluxed over a large exostosis, creating a snapping sound. Snapping of tendons is common around the hip, ankles, shoulder, and elbow, but rare at the knee. When it does occur, snapping about the knee can be due to discoid meniscus, rheumatoid nodules, synovial plicae, iliotibial band syndrome, congenital snapping knee, and snapping tendons. Research revealed only 5 previous cases due to subluxation of the biceps femoris tendon. The case we present is the only one due to an exostosis, as well as the only one that required bilateral surgical repair. The patient presented when his pain became significant enough to interfere with his ability to continue competitive cycling. PMID:18300673
Fung, Daniel A; Frey, Steven; Markbreiter, Lance
Summary Pectoralis major (PM) muscle is the powerful dynamic stabiliser of the shoulder that acts as a flexor, adductor and internal rotator. The rupture of the PM tendon is a relatively rare injury that was firstly described in a French boy by Patissier in 1822 and later, in 1861, by Letenneur who reported another similiar case. To date, over 200 cases have been published. In this article we describe the clinical anatomy and the mechanism of injuries of PM and we review the surgical procedures for acute and chronic ruptures.
Merolla, Giovanni; Paladini, Paolo; Campi, Fabrizio; Porcellini, Giuseppe
Surgical reconstruction and mobilization therapy for a retracted extensor hallucis longus laceration and tendon defect repaired by split extensor hallucis longus tendon lengthening and dermal scaffold augmentation.
A reconstructive technique and physical therapy protocol is presented for the treatment of extensor hallucis longus (EHL) lacerations with critical size defects caused by tendon retraction. The primary goal of treatment was to restore EHL structure and function without the use of a bridging allograft or tendon transfer. The technique is performed by split lengthening the distal segment of the lacerated EHL and rotating the lengthened segment proximally 180° to bridge the tendon defect. The lengthened tendon is then sutured to the proximal segment of the EHL. The EHL is then tubularized with an acellular dermal scaffold at the region of tendon rotation to improve tendon strength, minimize the probability of tendon overlengthening or re-rupture, and improve the tendon gliding motion, which can be compromised by the tendon irregularity caused by rotation of the tendon. Postoperative range of motion therapy should be initiated at 3 weeks postoperatively. A case report of this technique and postoperative mobilization protocol is presented. The American Orthopaedic Foot and Ankle Society midfoot score at 3 and 6 months postoperatively was 90 of 100. The patient regained active dorsiflexion motion of the hallux without functional limitations, deformity, or contracture of the hallux. The advantages of this technique include that a large cadaveric allograft is not needed to bridge a critical size tendon defect and tendon lengthening provides a biologically active tendon graft without the secondary comorbidities and dysfunction commonly associated with tendon transfer procedures. PMID:22658790
Joseph, Robert M; Barhorst, Jessica
Summary Tendon lesions are among the most frequent musculoskeletal pathologies. Vascular endothelial growth factor (VEGF) is known to regulate angiogenesis. VEGF-111, a biologically active and proteolysis-resistant splice variant of this family, was recently identified. This study aimed at evaluating whether VEGF-111 could have a therapeutic interest in tendon pathologies. Surgical section of one Achilles tendon of rats was performed before a local injection of either saline or VEGF-111. After 5, 15 and 30 days, the Achilles tendons of 10 rats of both groups were sampled and submitted to a biomechanical tensile test. The force necessary to induce tendon rupture was greater for tendons of the VEGF-111 group (p<0.05) while the section areas of the tendons were similar. The mechanical stress was similar at 5 and 15 days in the both groups but was improved for the VEGF-111 group at day 30 (p <0.001). No difference was observed in the mRNA expression of collagen III, tenomodulin and MMP-9. In conclusion, we observed that a local injection of VEGF-111 improves the early phases of the healing process of rat tendons after a surgical section. Further confirmatory experimentations are needed to consolidate our results.
Kaux, Jean-Francois; Janssen, Lauriane; Drion, Pierre; Nusgens, Betty; Libertiaux, Vincent; Pascon, Frederic; Heyeres, Antoine; Hoffmann, Audrey; Lambert, Charles; Le Goff, Caroline; Denoel, Vincent; Defraigne, Jean-Olivier; Rickert, Markus; Crielaard, Jean-Michel; Colige, Alain
We hypothesized that altered fate of tendon-derived stem cells (TDSCs) might contribute to chondro-ossification and failed healing in the collagenase-induced (CI) tendon injury model. This study aimed to compare the yield, proliferative capacity, immunophenotypes, senescence, and differentiation potential of TDSCs isolated from healthy (HT) and CI tendons. TDSCs were isolated from CI and healthy Sprague-Dawley rat patellar tendons. The yield, proliferative capacity, immunophenotypes, and senescence of TDSCs (CI) and TDSCs (HT) were compared by colony-forming unit assay, BrdU assay, flow cytometry, and ?-galactosidase activity assay, respectively. Their osteogenic and chondrogenic differentiation potentials and mRNA expression of tendon-related markers were compared using standard assays. More TDSCs, which showed a lower proliferative potential and a higher cellular senescence were present in the CI patellar tendons compared to HT tendons. There was a higher alkaline phosphatase activity and mineralization in TDSCs (CI) in both basal and osteogenic media. More chondrocyte-like cells and higher proteoglycan deposition, Sox9 and collagen type II expression were observed in TDSCs (CI) pellets upon chondrogenic induction. There was a higher protein expression of Sox9, but a lower mRNA expression of Col1a1, Scx, and Tnmd in TDSCs (CI) in a basal medium. In conclusion, TDSCs (CI) showed altered fate, a higher cellular senescence, but a lower proliferative capacity compared to TDSCs (HT), which might contribute to pathological chondro-ossification and failed tendon healing in this animal model.
Rui, Yun Feng; Wong, Yin Mei; Tan, Qi; Chan, Kai Ming
Background: Increase in expression of substance P (SP) and calcitonin gene-related peptide (CGRP) has been reported in clinical samples of tendinopathy.Purpose: To examine the spatial-temporal expression of these neuropeptides as well as their association with activity-related tendon pain, matrix degeneration, failed healing, and pathologic calcification in an established collagenase-induced tendon injury rat model.Study Design: Controlled laboratory study.Methods: Collagenase or saline
Pauline Po-Yee Lui; Lai-shan Chan; Sai-chuen Fu; Kai-ming Chan
Development and metaplasia of ossified tendons in two hadrosaurine dinosaurs (Maiasaura peeblesorum and Brachylophosaurus canadensis) are described by comparison with the known developmental processes of ossified tendons in turkeys (Meleagris gallopavo). Mineralized primary tendon tissue and replacement patterns suggest that ossified tendons in hadrosaurs grew initially in a manner similar to those in turkeys. That is, biomineralization begins with apatite
Jason S. Adams; Christopher L. Organ
Background: Although many studies involving rotator cuff repair fixation have focused on ultimate fixation strength and ability to restore the tendon’s native footprint, no studies have characterized the stability of the repair with regard to motion between the tendon and repair site footprint.Hypothesis: Suture anchor fixation for rotator cuff repair has greater interface motion between tendon and bone than does
Christopher S. Ahmad; Andrew M. Stewart; Rolando Izquierdo; Louis U. Bigliani
Tendons are composed of fibroblasts and collagen fibrils. The fibrils are organized uniaxially and grouped together into fibers. Collagen VI is a non-fibrillar collagen expressed in developing and adult tendons. Human collagen VI mutations result in muscular dystrophy, joint hyperlaxity and contractures. The purpose of this study is to determine the functional roles of collagen VI in tendon matrix assembly. During tendon development, collagen VI was expressed throughout the extracellular matrix, but enriched around fibroblasts and their processes. To analyze the functional roles of collagen VI a mouse model with a targeted inactivation of Col6a1 gene was utilized. Ultrastructural analysis of Col6a1?/? versus wild type tendons demonstrated disorganized extracellular micro-domains and collagen fibers in the Col6a1?/? tendon. In the col6a1?/? tendon, fibril structure and diameter distribution was abnormal compared to wild type controls. Col6a1?/? fibrils had smaller diameters and the diameter distributions were shifted significantly toward the smaller diameters. An analysis of fibril density (number/?m2) demonstrated an ~2.5 fold increase in the Col6a1?/? versus wild type tendons. In addition, the fibril arrangement and structure was aberrant in the peri-cellular regions of Col6a1?/? tendons with frequent very large fibrils and twisted fibrils observed restricted to this region. The biomechanical properties were analyzed in mature tendons. A significant decrease in cross sectional area was observed. The percent relaxation, maximum load, maximum stress, stiffness and modulus were analyzed and Col6a1?/? tendons demonstrated a significant reduction in maximum load and stiffness compared to wild type tendons. An increase in matrix metalloproteinase activity was suggested in the absence of collagen VI. This suggests alterations in tenocyte expression due to disruption of cell-matrix interactions. The changes in expression may result in alterations in the peri-cellular environment. In addition, the absence of collagen VI may alter the sequestering of regulatory molecules such as leucine rich proteoglycans. These changes would result in dysfunctional regulation of tendon fibrillogenesis indirectly mediated by collagen VI.
Izu, Yayoi; Ansorge, Heather L.; Zhang, Guiyun; Soslowsky, Louis J.; Bonaldo, Paolo; Chu, Mon-Li; Birk, David E.
Background We developed a novel technique to improve tendon-bone attachment by hybridizing calcium phosphate (CaP) with a tendon graft using an alternate soaking process. However, the long-term result with regard to the interface between the tendon graft and the bone is unclear. Methods We analyzed bone tunnel enlargement by computed tomography and histological observation of the interface and the tendon graft with and without the CaP hybridization 2 years after anterior cruciate ligament (ACL) reconstruction in goats using EndoButton and the postscrew technique (CaP, n = 4; control, n = 4). Results The tibial bone tunnel enlargement rates in the CaP group were lower than those in the control group (p < 0.05). In the CaP group, in the femoral and tibial bone tunnels at the anterior and posterior of the joint aperture site, direct insertion-like formation that contained a cartilage layer without tidemarks was more observed at the tendon-bone interface than in the control group (p < 0.05). Moreover, the gap area between the tendon graft and the bone was more observed at the femoral bone tunnel of the joint aperture site in the control group than in the CaP group (p < 0.05). The maturation of the tendon grafts determined using the ligament tissue maturation index was similar in both groups. Conclusions The CaP-hybridized tendon graft enhanced the tendon-bone healing 2 years after ACL reconstruction in goats. The use of CaP-hybridized tendon grafts can reduce the bone tunnel enlargement and gap area associated with the direct insertion-like formation in the interface near the joint.
Tendon-to-bone healing following acute injury is generally poor and often fails to restore normal tendon biomechanical properties. In recent years, the murine patellar tendon (PT) has become an important model system for studying tendon healing and repair due to its genetic tractability and accessible location within the knee. However, the mechanical properties of native murine PT, specifically the regional differences in tissue strains during loading, and the biomechanical outcomes of natural PT-to-bone healing have not been well characterized. Thus, in this study, we analyzed the global biomechanical properties and regional strain patterns of both normal and naturally healing murine PT at three time points (2, 5, and 8weeks) following acute surgical rupture of the tibial enthesis. Normal murine PT exhibited distinct regional variations in tissue strain, with the insertion region experiencing approximately 2.5 times greater strain than the midsubstance at failure (10.80±2.52% vs. 4.11±1.40%; mean±SEM). Injured tendons showed reduced structural (ultimate load and linear stiffness) and material (ultimate stress and linear modulus) properties compared to both normal and contralateral sham-operated tendons at all healing time points. Injured tendons also displayed increased local strain in the insertion region compared to contralateral shams at both physiologic and failure load levels. 93.3% of injured tendons failed at the tibial insertion, compared to only 60% and 66.7% of normal and sham tendons, respectively. These results indicate that 8weeks of natural tendon-to-bone healing does not restore normal biomechanical function to the murine PT following injury. PMID:24210849
Gilday, Steven D; Chris Casstevens, E; Kenter, Keith; Shearn, Jason T; Butler, David L
All patients with badminton-related acute Achilles tendon ruptures registered during 1990 to 1994 at the University Hospital of Umeå were retrospectively followed up using a questionnaire. Thirty-one patients (mean age, 36.0 years), 27 men and 4 women, were included. Thirty patients (97%) described themselves as recreational players or beginners. The majority of the injuries (29 of 31, 94%) happened at the middle or end of the planned game. Previous local symptoms had been noticed by five patients (16%). Long-term results showed that patients treated with surgery had a significantly shorter sick leave absence than patients treated without surgery (50 versus 75 days). There was no obvious selection favoring any treatment modality. None of the surgically treated patients had reruptures, but two reruptures occurred in the nonsurgically treated group. There seemed to be fewer remaining symptoms and a higher sports activity level after the injury in the surgically treated group. Our results indicate that local muscle fatigue may interfere with strength and coordination. Preventive measures such as specific treatment of minor injuries and adequate training of strength, endurance, and coordination are important. Our findings also indicate that surgical treatment and careful postoperative rehabilitation is of great importance among badminton players of any age or sports level with Achilles tendon rupture. PMID:9617415
Fahlström, M; Björnstig, U; Lorentzon, R
Abstract The purpose of this study was to measure the tension in the flexor digitorum profundus (FDP) tendon in zone II and the digit angle during joint manipulations that replicate rehabilitation protocols. Eight FDP tendons from eight human cadavers were used in this study. The dynamic tension in zone II of the tendon and metacarpophalangeal (MCP) joint angle were measured in various wrist and digit positions. Tension in the FDP tendon increased with MCP joint extension. There was no tension with the finger fully flexed and wrist extended (synergistic motion), but the tendon force reached 1.77 +/- 0.43 N with the MCP joint hyperextended 45 degrees with the distal interphalangeal and proximal interphalangeal joints flexed. The combination of wrist extension and MCP joint hyperextension with the distal interphalangeal and proximal interphalangeal joints fully flexed, what the authors term "modified synergistic motion," produced a modest tendon tension and may be a useful alternative configuration to normal synergistic motion in tendon rehabilitation. PMID:16059854
Tanaka, Tatsuro; Amadio, Peter C; Zhao, Chunfeng; Zobitz, Mark E; An, Kai-Nan
Gastrointestinal motility is ensured by the correct coordination of the enteric nervous system and the visceral smooth muscle cells (SMCs), and defective development of SMCs results in gut malformations and intestinal obstructions. In order to identify the molecular mechanisms that control the differentiation of the visceral mesenchyme into SMCs in the vertebrate stomach, we developed microarrays to analyze the gene expression profiles of undifferentiated and differentiated avian stomachs. We identify Scleraxis, a basic-helix-loop-helix transcription factor, as a new marker of stomach mesenchyme and find that expression of Scleraxis defines the presence of two tendons closely associated to the two visceral smooth muscles. Using targeted gene misexpression, we show that FGF signaling is sufficient to induce Scleraxis expression and to establish two tendon domains adjacent to the smooth muscle structures. We also demonstrate that the tendon organization is perturbed by altering Scleraxis expression or function. Moreover, using primary cells derived from stomach mesenchyme, we find that undifferentiated stomach mesenchyme can give rise to both SMCs and tendon cells. These data show that upon FGF activation, selected stomach mesenchymal cells are primed to express Scleraxis and to differentiate into tendon cells. Our findings identify a new anatomical and functional domain in the vertebrate stomach that we characterize as being two intermuscular tendons closely associated with the visceral SMC structures. We also demonstrate that the coordinated development of both tendon and smooth muscle domains is essential for the correct morphogenesis of the stomach. PMID:19176584
Le Guen, Ludovic; Notarnicola, Cécile; de Santa Barbara, Pascal
Tendons are composed of longitudinally aligned collagen fibrils arranged in bundles with an undulating pattern, called crimp. The crimp structure is established during embryonic development and plays a vital role in the mechanical behaviour of tendon, acting as a shock-absorber during loading. However, the mechanism of crimp formation is unknown, partly because of the difficulties of studying tendon development in vivo. Here, we used a 3D cell culture system in which embryonic tendon fibroblasts synthesise a tendon-like construct comprised of collagen fibrils arranged in parallel bundles. Investigations using polarised light microscopy, scanning electron microscopy and fluorescence microscopy showed that tendon constructs contained a regular pattern of wavy collagen fibrils. Tensile testing indicated that this superstructure was a form of embryonic crimp producing a characteristic toe region in the stress-strain curves. Furthermore, contraction of tendon fibroblasts was the critical factor in the buckling of collagen fibrils during the formation of the crimp structure. Using these biological data, a finite element model was built that mimics the contraction of the tendon fibroblasts and monitors the response of the Extracellular matrix. The results show that the contraction of the fibroblasts is a sufficient mechanical impulse to build a planar wavy pattern. Furthermore, the value of crimp wavelength was determined by the mechanical properties of the collagen fibrils and inter-fibrillar matrix. Increasing fibril stiffness combined with constant matrix stiffness led to an increase in crimp wavelength. The data suggest a novel mechanism of crimp formation, and the finite element model indicates the minimum requirements to generate a crimp structure in embryonic tendon. PMID:21735243
Herchenhan, Andreas; Kalson, Nicholas S; Holmes, David F; Hill, Patrick; Kadler, Karl E; Margetts, Lee
Although the subscapularis has historically received less attention than posterosuperior rotator cuff tears, repair of a torn subscapularis tendon is critically important to restoring anatomy and achieving the best functional outcome possible. Arthroscopic repair begins with proper recognition of the tear. A systematic approach can then be used to arthroscopically repair all types of subscapularis tendon tears, from partial tears to full-thickness tears, as well as those which are retracted and have adhesions medially. Subscapularis footprint restoration can be accomplished with a variety of repair techniques that must be matched to the extent of the tear and mobility of the tendon.
Denard, Patrick J.; Burkhart, Stephen S.
The patient was a 47-year-old man who was evaluated by a physical therapist for a chief complaint of posterior right elbow pain. The patient routinely participated in weightlifting activities and reported a sudden onset of triceps weakness and posterior elbow pain while performing clap push-ups 3 days prior. A physician assistant ordered radiographs, which were initially interpreted as normal, and routine magnetic resonance imaging for the right elbow. Following examination by a physical therapist, due to concern for a triceps tendon tear, the previously ordered magnetic resonance imaging was expedited, which revealed a partial triceps tendon tear with partial tendon retraction medially. PMID:24175622
Molloy, Joseph M; Aberle, Curtis J; Escobar, Eduardo
Ossification of the Achilles tendon (OTA) is an unusual clinical condition. It is characterized by the presence of an ossified mass within the fibrocartilaginous substance of the Achilles tendon. The etiology of the ossification of the Achilles tendon is unknown. Review of the literature suggests that its etiology is multifactorial. The major contributing factors are trauma and surgery with other minor causes such as systemic diseases, metabolic conditions, and infections. To our knowledge, no previous reports suggest any genetic/hereditary predisposition in OAT. We report 3 siblings who have OAT with no history of any of the aforementioned predisposing factors. Could OAT have a hereditary component as one of its etiologies?
The preferred treatment of distal biceps tendon ruptures is by operative repair. However, the best approach for repair (single vs double incision) is still subject of debate. Grewal and colleagues recently presented the results of a randomized clinical trial evaluating two different surgical approaches for the repair of distal biceps tendon ruptures. Despite the fact that this article currently presents the highest level of evidence for the surgical repair of distal biceps tendon ruptures, we have some comments on the study that might be interesting to discuss. We think that some of the results and conclusions presented in this study need to be interpreted in the light of these comments.
Kodde, Izaak F; van den Bekerom, Michel P J; Eygendaal, Denise
Although the subscapularis has historically received less attention than posterosuperior rotator cuff tears, repair of a torn subscapularis tendon is critically important to restoring anatomy and achieving the best functional outcome possible. Arthroscopic repair begins with proper recognition of the tear. A systematic approach can then be used to arthroscopically repair all types of subscapularis tendon tears, from partial tears to full-thickness tears, as well as those which are retracted and have adhesions medially. Subscapularis footprint restoration can be accomplished with a variety of repair techniques that must be matched to the extent of the tear and mobility of the tendon. PMID:24400185
Denard, Patrick J; Burkhart, Stephen S
In vitro cell studies might be a useful tool for studying tendon pathology, but no suitable in vitro models exist for tendon disorders. The purpose of this study was to confirm whether cell scratch culture using tendon-derived fibroblasts can provide a suitable in vitro tendon disorder model. Extracellular matrix components were examined immunohistochemically in tendon tissue, and then their related gene expression levels were analyzed by conventional reverse transcription polymerase chain reaction (RT-PCR) and/or quantitative real-time RT-PCR in tissues and cells. Collagen type I (Col I), collagen type III (Col III), tenascin-C (TN-C) and cartilage oligomeric matrix protein (COMP) were detected in tendon tissue sections, and RT-PCR confirmed their expression in tendon tissue and cells. Cells that had been cultured from explanted tendon tissue maintained the characteristics of in vivo tendon cells. The combination of TN-C and COMP might be a useful marker of tendon cells because they display more tendon-specific expression than Col I and III. In particular, the significant increase of TN-C mRNA expression in the scratch wound assay, at 12 hr after scratching, concomitant with the regeneration of the cell sheet, indicates its crucial role in tendon cell proliferation and migration. Thus, TN-C appears to be a key factor in tendon wound healing. In vitro cell scratch assays using tendon cells appear to mimic the repair of tendon tissue after injury.
NEMOTO, Manabu; KIZAKI, Keiichiro; YAMAMOTO, Yoshio; OONUMA, Toshina; HASHIZUME, Kazuyoshi
Background. The optimal surgical treatment for Kienböck's disease with stages IIIB and IV remains controversial. A cadaver study was carried out to evaluate the use of coiled extensor carpi radialis longus tendon for tendon interposition and a strip obtained from the same tendon for ligament reconstruction in the late stages of Kienböck's disease. Methods. Coiled extensor carpi radialis longus tendon was used to fill the cavity of the excised lunate, and a strip obtained from this tendon was sutured onto itself after passing through the scaphoid and the triquetrum acting as a ligament to preserve proximal row integrity. Biomechanical tests were carried out in order to evaluate this new ligamentous reconstruction. Results. It was biomechanically confirmed that the procedure was effective against axial compression and distributed the upcoming mechanical stress to the distal row. Conclusion. Extensor carpi radialis longus tendon has not been used for tendon interposition and ligament reconstruction in the treatment of this disease before. In view of the biomechanical data, the procedure seems to be effective for the stabilization of scaphoid and carpal bones.
Karalezli, Naz?m; Uz, Aysun; Esmer, Ali F?rat; Demirtas, Mehmet; Tasc?, Arzu Gul; Kutahya, Harun; Ulusoy, Gurhan
Flexor tendon injuries are often encountered clinically and typically require surgical repair. Return of function after repair is limited due to adhesion formation, which leads to reduced tendon gliding, and due to a lack of repair site strength, which leads to repair site gap formation or rupture. The application of the growth factors basic fibroblastic growth factor (bFGF) and platelet derived growth factor BB (PDGF-BB) has been shown to have the potential to enhance tendon healing. The objectives of this study were to examine: (1) the conditions over which delivery of bFGF can be controlled from a heparin-binding delivery system (HBDS) and (2) the effect of bFGF and PDGF-BB released from this system on tendon fibroblast proliferation and matrix gene expression in vitro over a 10-day interval. Delivery of bFGF was controlled using a HBDS. Fibrin matrices containing the HBDS retained bFGF better than did matrices lacking the delivery system over the 10-day period studied. Delivery of bFGF and PDGF-BB using the HBDS stimulated tendon fibroblast proliferation and promoted changes in the expression of matrix genes related to tendon gliding, strength, and remodeling. Both growth factors may be effective in enhancing tendon healing in vivo.
Thomopoulos, Stavros; Das, Rosalina; Sakiyama-Elbert, Shelly; Silva, Matthew J.; Charlton, Nichole; Gelberman, Richard H.
Minimally invasive trauma and orthopedic surgery is increasingly common, though technically demanding. Its use for pathologies of the Achilles tendon (AT) hold the promise to allow faster recovery times, shorter hospital stays, and improved functional outcomes when compared to traditional open procedures, which can lead to difficulty with wound healing because of the tenuous blood supply and increased chance of wound breakdown and infection. We present the recent advances in the field of minimally invasive AT surgery for tendinopathy, acute ruptures, chronic tears, and chronic avulsions of the AT. In our hands, minimally invasive surgery has provided similar results to those obtained with open surgery, with decreased perioperative morbidity, decreased duration of hospital stay, and reduced costs. So far, the studies on minimally invasive orthopedic techniques are of moderate scientific quality with short follow-up periods. Multicenter studies with longer follow-up are needed to justify the long-term advantages of these techniques over traditional ones.
Maffulli, Nicola; Longo, Umile Giuseppe; Spiezia, Filippo; Denaro, Vincenzo
The aging population is at an increased risk of tendon injury and tendinopathy. Elucidating the molecular basis of tendon aging is crucial to understanding the age-related changes in structure and function in this vulnerable tissue. In this study, the structural and functional features of tendon aging are investigated. In addition, the roles of decorin and biglycan in the aging process were analyzed using transgenic mice at both mature and aged time points. Our hypothesis is that the increase in tendon injuries in the aging population is the result of altered structural properties that reduce the biomechanical function of the tendon and consequently increase susceptibility to injury. Decorin and biglycan are important regulators of tendon structure and therefore, we further hypothesized that decreased function in aged tendons is partly the result of altered decorin and biglycan expression. Biomechanical analyses of mature (day 150) and aged (day 570) patellar tendons revealed deteriorating viscoelastic properties with age. Histology and polarized light microscopy demonstrated decreased cellularity, alterations in tenocyte shape, and reduced collagen fiber alignment in the aged tendons. Ultrastructural analysis of fibril diameter distributions indicated an altered distribution in aged tendons with an increase of large diameter fibrils. Aged wild type tendons maintained expression of decorin which was associated with the structural and functional changes seen in aged tendons. Aged patellar tendons exhibited altered and generally inferior properties across multiple assays. However, decorin-null tendons exhibited significantly decreased effects of aging compared to the other genotypes. The amelioration of the functional deficits seen in the absence of decorin in aged tendons was associated with altered tendon fibril structure. Fibril diameter distributions in the decorin-null aged tendons were comparable to those observed in the mature wild type tendon with the absence of the subpopulation containing large diameter fibrils. Collectively, our findings provide evidence for age-dependent alterations in tendon architecture and functional activity, and further show that lack of stromal decorin attenuates these changes.
Dunkman, Andrew A.; Buckley, Mark R.; Mienaltowski, Michael J.; Adams, Sheila M.; Thomas, Stephen J.; Satchell, Lauren; Kumar, Akash; Pathmanathan, Lydia; Beason, David P.; Iozzo, Renato V.; Birk, David E.; Soslowsky, Louis J.
KEVLAR is a high strength, high modulus synthetic fiber manufactured by the E.I. DuPont de Nemours Company. The fiber is resistant to chloride and alkali attack. The resistance is enhanced when the fibers are assembled into a resin matrix and fabricated as rods. These properties suggest that KEVLAR reinforced rods may be a substitute for high strength steel prestress tendons in certain applications such as bridge decks and parking structures. This dissertation presents the background, theoretical development, and experimental investigations of KEVLAR reinforced rod strength, anchorage, fabrication and performance in prestressed concrete structures. The study concludes that KEVLAR has significant potential for these prestressed concrete applications. However, the reliability of the long term anchorage of the KEVLAR reinforced rods must be improved before production applications are undertaken. KEVLAR has a low shear strength compared to its tensile capacity. The anchorage of KEVLAR reinforced rods is sensitive to the shear forces generated in the anchorage assembly. Finite element analyses, using interface elements to simulate the addition of a mold release agent in a conic anchor, predict the behavior of resin socketed anchors. Test results confirm that mold release agents reduce the anchor shear stresses and suggest that moderate strength resins may be used in the anchor. KEVLAR is nearly linearly elastic to failure, yet ductility of a structure is an important design concern. Prestressed concrete beam tests using both bonded and unbonded tendons demonstrated that ductile structural behavior is obtained. Methods of predicting the strength and deflection behavior of the prestressed beams are presented and the theoretical predictions are compared to the experimental results. The overall correlation between predicted and theoretical results is satisfactory.
Crovace, A., Lacitignola, L., De siena, R., Rossi, G. and Francioso, E., 2007. Cell therapy for tendon repair in horses: An\\u000a experimental study. Veterinary Research Communications, 31(Suppl. 1), 281–283
A. Crovace; L. Lacitignola; R. De siena; G. Rossi; E. Francioso
... Subscribe Protect Your Tendons Preventing the Pain of Tendinitis You’ve probably heard of such sports injuries ... jumper’s knee. These are just 2 examples of tendinitis, a painful condition caused by overusing and straining ...
Rupture of the distal biceps tendon is a relatively un- common clinical entity. Typically, patients are middle-aged males who experience a sudden forced extension against an actively con- tracting biceps muscle. Patients usually describe a \\
WILLIAM HAMILTON; MATTHEW L. RAMSEY
Few case reports have described the surgical treatment of calcifying tendonitis of the subscapularis tendon. We present a case of symptomatic diffuse calcifying tendonitis involving the subscapularis and infraspinatus insertions that was difficult to detect arthroscopically. The patient was treated with arthroscopic incision of the tendinous insertions thorough removal of the calcific deposits and subsequent repair using a suture-anchor technique. Two years after the surgical procedure, the patient was completely pain-free and attained full range of motion. Radiographic evaluation performed 2 years after the procedure revealed no calcific deposits. We conclude that the combination of incision of the subscapularis and infraspinatus insertions, complete removal of the calcific deposits, and subsequent suture-anchor repair in an all-arthroscopic manner can lead to an excellent clinical outcome without compromising the functional integrity of the rotator cuff tendons.
Mitsui, Yasuhiro; Gotoh, Masafumi; Tanesue, Ryo; Shirachi, Isao; Shibata, Hideaki; Nakama, Kenjiro; Okawa, Takahiro; Higuchi, Fujio; Nagata, Kensei
OBJECTIVE: The purpose of this study was to histologically analyze allografts from cadaveric semitendinous muscle after cryopreservation at ?80°C in comparison to a control group kept at only ?4°C to test the hypothesis that the histological characteristics of the tissue are maintained when the tendons are kept at lower temperatures. METHODS: In a tissue bank, 10 semitendinous tendons from 10 cadavers were frozen at ?80ºC as a storage method for tissue preservation. They were kept frozen for 40 days, and then a histological study was carried out. Another 10 tendon samples were analyzed while still “fresh”. RESULTS: There was no histological difference between the fresh and frozen samples in relation to seven variables. CONCLUSIONS: Semitendinous muscle tendon allografts can be submitted to cryopreservation at ?80ºC without suffering histological modifications.
Bitar, Alexandre Carneiro; Santos, Luiz Augusto Ubirajara; Croci, Alberto Tesconi; Pereira, Joao Alberto Ramos Maradei; Franca Bisneto, Edgard N.; Giovani, Arlete Mazzini Miranda; Oliveira, Claudia Regina G. C. M.
Summary Over the past five decades we have seen numerous iterations of suture repair methods for tendon. The pursuit of the ultimate repair has led to many repair methods being described. This comprehensive compilation of the suture repair techniques will describe the factors that affect repair success, including repair strength, gapping resistance, glide and rehabilitation. Different approaches to rejoining severed tendons will be critiqued on their biomechanical ability to improve tendon repair strength, maintaining glide, reducing tendon damage, and minimising adhesion formation. It is important to highlight how the suture repairs have evolved and improved but also review how they may contribute to their own trauma. The apparent paradox between providing mechanical strength and minimising adhesions require refinements in the field to improve on functional outcomes.
Rawson, Shelley; Cartmell, Sarah; Wong, Jason
The intrasynovial bone-tendon interface is a gradual transition from soft tissue to bone, with two intervening zones of uncalcified and calcified fibrocartilage. Following injury, the native anatomy is not restored, resulting in inferior mechanical properties and an increased risk of re-injury. Recent in vivo studies provide evidence of improved healing when surgical repair of the bone-tendon interface is augmented with cells capable of undergoing chondrogenesis. In particular, cellular therapy in bone-tendon healing can promote fibrocartilage formation and associated improvements in mechanical properties. Despite these promising results in animal models, cellular therapy in human patients remains largely unexplored. This review highlights the development and structure-function relationship of normal bone-tendon insertions. The natural healing response to injury is discussed, with subsequent review of recent research on cellular approaches for improved healing. Finally, opportunities for translating in vivo findings into clinical practice are identified.
Rothrauff, Benjamin B; Tuan, Rocky S
Background: Although knee injuries are common among professional football players, ruptures of the patellar tendon are relatively rare. Predisposing factors, mechanisms of injury, treatment guidelines, and recovery expectations are not well established in high-level athletes.Hypothesis: Professional football players with isolated rupture of the patellar tendon treated with timely surgical repair will return to their sport.Study Design: Case series; Level of
Martin Boublik; Theodore Schlegel; Ryan Koonce; James Genuario; Charles Lind; David Hamming
\\u000a Ligaments and tendons are non-linear viscoelastic materials and their response functions are typically assessed using creep\\u000a and stress relaxation tests. Non-linear viscoelastic models such as multiple Maxwell elements in parallel and the quasilinear\\u000a viscoelastic model (QLV) used to capture the non-linear viscoelastic response of ligaments and tendons frequently employ multiple\\u000a relaxation time constants determined from curve-fitting the entire available data
Jinjin Ma; Ellen M. Arruda
Background: Isolated and combined subscapularis tendon tears are rare and are described in the literature only in small numbers.Hypothesis: The outcome of surgical intervention for isolated and combined subscapularis tendon tears may be influenced by the tear pattern of the anterior rotator cuff and the period of time between trauma and surgical procedure.Study Design: Case series; Level of evidence, 4.Methods:
Peter C. Kreuz; Andreas Remiger; Christoph Erggelet; Stefan Hinterwimmer; Philipp Niemeyer; Andre Gächter
Purpose: Various surgical repair techniques for distal biceps tendon ruptures have been reported, however, the optimal technique is unknown. Methods: Over a 4-year period 19 distal biceps tendon ruptures were repaired: 9 using a single anterior incision and 10 using a modified 2-incision Boyd and Anderson technique. The patients were followed-up prospectively and independently reviewed. Results: Patient-rated elbow evaluation and
Ron El-Hawary; Joy C. MacDermid; Kenneth J. Faber; Stuart D. Patterson; Graham J. W. King
Extensor hallucis longus tendon contracture can lead to hyperextension deformity of the big toe. We describe an endoscopic\\u000a approach of Z-lengthening of the tendon. Extensor hallucis longus tendoscopy is performed with a distal portal at the level\\u000a of the metatarsal neck and a proximal portal at the level of the navicular. At the distal portal, the medial half of the
T. H. Lui
With the role of the biceps tendon being the source of considerable controversy, the treatment of its disease has been even more confusing. Our understanding of its role in shoulder pathology has ranged from describing it as a vestigial structure, to a vital structure of shoulder function with distinct disease pathology. This chapter analyzes the anatomic and biomechanical functions of the proximal biceps tendon. PMID:18703968
SUMMARY Although post-rehabilitation is routinely performed following flexor tendon repair, in some clinical scenarios post-rehabilitation must be delayed. We investigated modification of the tendon surface using carbodiimide derivatized hyaluronic acid and lubricin (cd-HA-Lub) to maintain gliding function following flexor tendon repair with postoperative immobilization in a in vivo canine model. Flexor digitorum profundus tendons from the 2nd and 5th digits of one forepaw of six dogs were transected and repaired. One tendon in each paw was treated with cd-HA-Lub; the other repaired tendon was not treated. Following tendon repair, a forearm cast was applied to fully immobilize the operated forelimb for 10 days, after which the animals were euthanized. Digit normalized work of flexion (nWOF) and tendon gliding resistance were assessed. The nWOF of the FDP tendons treated with cd-HA-Lub was significantly lower than the nWOF of the untreated tendons (p < 0.01). The gliding resistance of cd-HA-Lub treated tendons was also significantly lower than that of the untreated tendons (p < 0.05). Surface treatment with cd-HA-Lub following flexor tendon repair provides an opportunity to improve outcomes for patients in whom the post-operative therapy must be delayed after flexor tendon repair.
Zhao, Chunfeng; Sun, Yu-Long; Jay, Gregory D.; Moran, Steven L.; An, Kai-Nan; Amadio, Peter C.
Due to their superficial course, the extensor tendons are frequently lacerated over the dorsum of the hand and fingers. Excellent functional results are obtained in repairs of simple tendon lacerations. ‘Open’ mallet lacerations over the distal IP joint or involving the central extensor slip over the proximal IP joint require more precise suturing methods. More proximal extensor tendon divisions near the wrist involve dissection of the retracted finger extensors or long thumb extensor in the distal forearm and more formal tendon repairs, including a possible tendon transfer to the thumb. ‘Closed injuries’, with varying degrees of extensor tendon disruption, occur at three main sites. The mallet injury at the DIP joint and the boutonnière deformity over the PIP joint are sometimes recognized late, but respond to conservative splinting for a minimum of four weeks with guarded motion avoiding secondary stiffening of the remaining small joints of the hand. Surgery of closed injuries most frequently involves the intra-articular traction fracture type of mallet deformities in which the DIP joint has taken the brunt of the injury.
Kontor, J. A.
Rotator cuff tears represent the most common shoulder injuries in the United States. The debilitating effect of this degenerative condition coupled with the high incidence of failure associated with existing graft choices underscores the clinical need for alternative grafting solutions. The 2 critical design criteria for the ideal tendon graft would require the graft to not only exhibit physiologically relevant mechanical properties but also be able to facilitate functional graft integration by promoting the regeneration of the native tendon-to-bone interface. Centered on these design goals, this review will highlight current approaches to functional and integrative tendon repair. In particular, the application of biomimetic design principles through the use of nanofiber- and nanocomposite-based scaffolds for tendon tissue engineering will be discussed. This review will begin with nanofiber-based approaches to functional tendon repair, followed by a section highlighting the exciting research on tendon-to-bone interface regeneration, with an emphasis on implementation of strategic biomimicry in nanofiber scaffold design and the concomitant formation of graded multi-tissue systems for integrative soft-tissue repair. This review will conclude with a summary and discussion of future directions. PMID:22244070
Zhang, Xinzhi; Bogdanowicz, Danielle; Erisken, Cevat; Lee, Nancy M; Lu, Helen H
Objective: The aim of this study was to determine the effects of resveratrol on the tendon healing process of streptozotocin-induced diabetic rats. Methods: The study included 16 male Sprague-Dawley rats. Streptozotocin was administered to induce diabetes and bilateral tenorrhaphy of the Achilles tendons was performed. Intraperitoneal resveratrol was injected in the experimental group (n=8) and saline in the control group (n=8) during the postoperative period. Rats were sacrificed at the 14th day. Right side tendons were evaluated biomechanically and left side tendons histologically. Results: Difference in mean tendon tensile strength was not statistically significant between groups (p>0.05). Histologic evaluations of the repair zones showed greater configuration of the newly synthesized collagen in the experimental group. The ratio of the newly synthesized collagen area to the healing region area was significantly higher in the experimental group then the control group (p<0.01). Conclusion: Resveratrol appears to have a positive impact on the process of tendon healing in diabetic conditions in the first 14 days. PMID:24901929
Zeytin, Kayhan; Cilo?lu, Nesibe Sinem; Ate?, Filiz; Vardar Aker, Fugen; Ercan, Feriha
The authors devised an alternative arthroscopic double bundle ACL reconstruction technique using a bone patellar tendon bone (BPTB)-gracilis tendon composite autograft. One tibial and two femoral tunnels were used to reconstruct two bundles of anterior cruciate ligaments (ACL) [an anteromedial bundle (AM) and a post-erolateral bundle (PL)]. BTBB was fixed in the tunnels produced on the isometric points of the tibia and femur using the conventional technique. The gracilis tendon was then fixed in a PL tunnel produced using the outside-in technique. The authors consider that the devised technique based on a combination of autogenous bone patellar bone graft and gracilis tendon, can minimize tunnel widening post-operatively, allow easier revision should the reconstructed ACL fail, and also provides an alternative means of restoring rotation stability. PMID:18066529
Jung, Kwang Am; Lee, Su Chan; Song, Moon Bok; Lee, Choon Key
Muscle tendon unit (MTU) transfer is a common procedure performed to restore hand function after peripheral nerve or spinal cord injury. The principles of MTU transfer established for hand surgery can be adopted to optimize the dynamic excursion of the temporalis tendon transfer procedure for facial reanimation. Additionally, the force generating ability of a transferred MTU depends on the ideal length-tension relationship of the donor muscle. There are unclear guideline for selecting the ideal tension at which a transferred MTU will generate maximum force and excursion and current practice often leads to overstretch and suboptimal actin myosin interaction. The use of intraoperative electrical stimulation is an option for determining the ideal tension to optimize excursion of transferred temporalis tendon units in simile restoration. Understanding the biomechanics and principles of MTU and applying it to the temporalis tendon transfer procedure is necessary to improve its use in facial reanimation. PMID:23208742
Boahene, Kofi D O
ABSTRACT We report here the clinical presentation, magnetic resonance imaging (MRI) findings and successful surgical management associated with triceps tendon avulsion in a dog. A definitive diagnosis of triceps tendon avulsion was made based on MRI with evidence of displacement of the triceps tendon. Surgical correction of triceps tendon avulsion was performed with two horizontal mattress sutures using polyester and two tunnels drilled in the olecranon to reattach the tendon to the proximal olecranon. At 9 months, there was no evidence of lameness on the left thoracic limb. This is the first case report to describe MRI evaluation for the diagnosis of the triceps tendon avulsion.
YOON, Hun-Young; JEONG, Soon-Wuk
We report here the clinical presentation, magnetic resonance imaging (MRI) findings and successful surgical management associated with triceps tendon avulsion in a dog. A definitive diagnosis of triceps tendon avulsion was made based on MRI with evidence of displacement of the triceps tendon. Surgical correction of triceps tendon avulsion was performed with two horizontal mattress sutures using polyester and two tunnels drilled in the olecranon to reattach the tendon to the proximal olecranon. At 9 months, there was no evidence of lameness on the left thoracic limb. This is the first case report to describe MRI evaluation for the diagnosis of the triceps tendon avulsion. PMID:23708931
Yoon, Hun-Young; Jeong, Soon-Wuk
We have developed a new device to measure the friction force and calculate the friction coefficient between a rabbit flexor tendon, a pulley and a proximal phalanx. The flexor digitorum fibularis tendon of a rabbit was taken intact with the proximal phalanx, and tendon pulleys were attached to both ends of the bone. Both ends of the tendon were clamped to acrylic plates and connected to stainless-steel plates equipped with strain gauges. A pretension of 1.96 N was applied so as not to loosen the tendon. The proximal phalanx was fixed to an acrylic plate on the actuator, which gave 8 mm of transfer to the acrylic plate at a speed of 2 mm/s. The interface between the tendon and the surrounded tissue created the friction force, when the load was applied on the distal pulley. The friction force could be obtained from the difference between the tension of both ends of the tendon, which was measured with strain gauges and sampled with a personal computer. The friction force and the friction coefficient were calculated from the measured force and the applied load. The load and the pre-loading time, which was defined as loading duration before gliding, were varied in order to observe the change of the friction coefficient. The friction coefficient was not affected by the load and increased with the pre-loading time. The value of mu(s) ranged from 0.027 to 0.111 (0.072 +/- 0.023), and that of (mu)d ranged from 0.010 to 0.069 (0.039 +/- 0.014) (pre-loading time was 5 s). Our method will allow for the examination of various surgical treatments and lubricants. Moreover, it can be applied to other tissues of any animals with similar structures to the rabbit's digitorum. PMID:10476853
Moro-oka, T; Miura, H; Higaki, H; Arimura, S; Mawatari, T; Murakami, T; Iwamoto, Y
Quantitative ultrasound (QUS) techniques have recently been widely applied for the characterization of tissues. For example, they can be used for the quantification of Achilles tendon properties based on the broadband ultrasound attenuation (BUA) and the speed of sound (SOS) when the ultrasound wave passes through the tissues. This study is to develop an integrated system to investigate the properties of Achilles tendons using QUS images from UBIS 5000 (DMS, Montpellier, France) and B-mode ultrasound images from HDI 5000 (ATL, Ultramark, USA). Subjects including young (32 females and 17 males; mean age: 23.7 ± 2.0) and middle-aged groups (8 female and 8 males; mean age: 47.3 ± 8.5 s) were recruited and tested for this study. Only subjects who did not exercise regularly and had no record of tendon injury were studied. The results show that the BUA is significantly higher for the young group (45.2 ± 1.6 dB MHz-1) than the middle-age group (40.5 ± 1.9 dB MHz-1), while the SOS is significantly lower for the young (1601.9 ± 11.2 ms-1) compared to the middle-aged (1624.1 ± 8.7 m s-1). On the other hand, the thicknesses of Achilles tendons for both groups (young: 4.31 ± 0.23 mm; middle age: 4.24 ± 0.23 mm) are very similar. For one patient who had an Achilles tendon lengthening (ATL) surgery, the thickness of the Achilles tendon increased from 4 mm to 4.33 mm after the surgery. In addition, the BUA increased by about 7.2% while the SOS decreased by about 0.6%. In conclusion, noninvasive ultrasonic assessment of Achilles tendons is useful for assisting clinical diagnosis and for the evaluation of a therapeutic regimen.
Du, Yi-Chun; Chen, Yung-Fu; Chen, Pei-Jarn; Lin, Yu-Ching; Chen, Tainsong; Lin, Chii-Jeng
Three percent of all biceps tendon ruptures occur at the distal aspect, where the tendon inserts into the radial tuberosity. Distal bicep tendon ruptures typically occur in middle-aged males after an eccentric extension load is applied to the elbow. Patients usually complain of a sudden, sharp, and painful tearing sensation in the antecubital region, with a palpable defect. The biceps squeeze and hook tests are specific maneuvers by which to diagnose distal biceps ruptures on physical examination. Magnetic resonance imaging (MRI) or ultrasound maybe be helpful to distinguish between partial and complete tears. Anatomic studies suggest there are two distinct insertions for the short and long heads of the distal biceps. The short head may be a more powerful flexor, and the long head may be a more powerful supinator. Nonoperative treatment typically results in loss of flexion and supination strength and endurance. Early anatomic re-attachment is the goal. Surgical approaches include one- or two-incision techniques, and tendon fixation methods include the use of suture anchors, bone tunnels, an endobutton, or biotenodesis screws. Biomechanical studies have shown that endobuttons have higher load-to-failure strengths, compared to the other fixation methods. However, clinical studies have demonstrated that patients do well regardless of surgical approach or fixation method. Possible complications include nerve injuries, heterotopic ossification, postoperative fracture, tendon rerupture, complex regional pain syndrome, and wound infection. Partial ruptures are significantly less common and initially can be treated conservatively. Chronic tears are more difficult to treat because of possible tendon retraction and poor tissue quality. Tendon grafts using semitendinosus, fascia lata, hamstring, Achilles (calcaneal), or flexor carpi radialis have been successfully used for length restoration in these cases. PMID:20632985
Quach, Tony; Jazayeri, Reza; Sherman, Orrin H; Rosen, Jeffrey E
The extracellular matrix (ECM) of connective tissues enables linking to other tissues, and plays a key role in force transmission and tissue structure maintenance in tendons, ligaments, bone and muscle. ECM turnover is influenced by physical activity, and both collagen synthesis and metalloprotease activity increase with mechanical loading. This can be shown by determining propeptide and proteinase activity by microdialysis, as well as by verifying the incorporation of infused stable isotope amino acids in biopsies. Local tissue expression and release of growth factors for ECM such as IGF-1, TGF-beta and IL-6 is enhanced following exercise. For tendons, metabolic activity (e.g. detected by positron emission tomography scanning), circulatory responses (e.g. as measured by near-infrared spectroscopy and dye dilution) and collagen turnover are markedly increased after exercise. Tendon blood flow is regulated by cyclooxygenase-2 (COX-2)-mediated pathways, and glucose uptake is regulated by specific pathways in tendons that differ from those in skeletal muscle. Chronic loading in the form of physical training leads both to increased collagen turnover as well as to some degree of net collagen synthesis. These changes modify the mechanical properties and the viscoelastic characteristics of the tissue, decrease its stress-susceptibility and probably make it more load-resistant. The mechanical properties of tendon fascicles vary within a given human tendon, and even show gender differences. The latter is supported by findings of gender-related differences in the activation of collagen synthesis with exercise. These findings may provide the basis for understanding tissue overloading and injury in both tendons and skeletal muscle.
Kjaer, Michael; Magnusson, Peter; Krogsgaard, Michael; M?ller, Jens Boysen; Olesen, Jens; Heinemeier, Katja; Hansen, Mette; Haraldsson, Bjarki; Koskinen, Satu; Esmarck, Birgitte; Langberg, Henning
Disorders of the flexor carpi radialis tendon (FCRt) are often missed even though they are a relatively frequent cause of volar radial wrist pain. They can manifest as tenosynovitis, tendinopathy, synovial sheath cysts with or without scaphoid-trapezoid-trapezium (STT) joint pathology, and partial or complete rupture. Because FCRt disorders often present with non-specific symptoms and a non-diagnostic clinical examination, imaging is often necessary for accurate evaluation and therapeutic planning. Conventional radiography provides good visualization of the neighboring bones and joints, as well as rare intratendinous calcifications. MRI enables evaluation of the FCRt and adjacent anatomical structures with excellent tissue resolution. In comparison, ultrasound (US) evaluation of the FCRt is less commonly described in the radiology literature, despite its affordability, exquisite soft tissue resolution, and the advantages of quick, dynamic diagnostic imaging. This pictorial essay describes and demonstrates the normal anatomy of the FCRt, its US examination technique and normal US appearance, and US findings of clinically relevant FCRt disorders. PMID:24658615
Luong, Dien Hung; Smith, Jay; Bianchi, Stefano
The pathogenesis and management of lateral epicondylalgia, or tennis elbow, a common ailment affecting middle-aged subjects of both genders continue to provoke controversy. Currently it is thought to be due to local tendon pathology, pain system changes, and motor system impairment. Its diagnosis is usually clinical, based on a classical history, as well as symptoms and signs. In selected cases, additional imaging (X-rays, ultrasound, and magnetic resonance imaging) can help to confirm the diagnosis. Different treatment modalities have been described, including the use of orthotics, non-steroidal anti-inflammatory drugs, steroid injections, topical glyceryl trinitrate, exercise therapy, manual therapy, ultrasound therapy, laser therapy, extracorporeal shockwave therapy, acupuncture, taping, platelet-rich plasma injections, hyaluronan gel injections, botulinum toxin injections, and surgery. Nevertheless, evidence to select the best treatment is lacking and the choice of therapy depends on the experience of the management team, availability of the equipment and expertise, and patient response. This article provides a snapshot of current medical practice for lateral epicondylalgia management. PMID:24584568
Luk, James K H; Tsang, Raymond C C; Leung, H B
A 27-year-old, right-hand-dominant woman with a posttraumatic anterior shoulder dislocation 3 months earlier after traffic accident presented because of pain and limited range of motion in the right shoulder. On physical examination, the patient had negative instability tests and a sulcus sign. On arthroscopic examination, a bifurcate long biceps tendon with two limbs was observed about 1 cm distal to the origin in the supraglenoid tubercle. We found no evidence of a tear in the long biceps tendon on probing, and the margin of each limb was smooth and round. Although this anatomic variant may be benign, its presence might be associated with other shoulder pathology. It is interesting to speculate whether the aberrant biceps anatomy in our patient contributed to transfer of injury at dislocation to the rotator cuff rather than to the classic anterior-inferior capsulolabral complex. In addition, recognition of the described anatomic variant on arthroscopy can aid the shoulder surgeon in focusing treatment on the actual pathology. PMID:17622545
Kim, Kyung Cheon; Rhee, Kwang Jin; Shin, Hyun Dae; Kim, Young Mo
Although the link between altered stem cell properties and tissue aging has been recognized, the molecular and cellular processes of tendon aging have not been elucidated. As tendons contain stem/progenitor cells (TSPC), we investigated whether the molecular and cellular attributes of TSPC alter during tendon aging and degeneration. Comparing TSPC derived from young/healthy (Y-TSPC) and aged/degenerated human Achilles tendon biopsies (A-TSPC), we observed that A-TSPC exhibit a profound self-renewal and clonogenic deficits, while their multipotency was still retained. Senescence analysis showed a premature entry into senescence of the A-TSPC, a finding accompanied by an upregulation of p16(INK4A). To identify age-related molecular factors, we performed microarray and gene ontology analyses. These analyses revealed an intriguing transcriptomal shift in A-TSPC, where the most differentially expressed probesets encode for genes regulating cell adhesion, migration, and actin cytoskeleton. Time-lapse analysis showed that A-TSPC exhibit decelerated motion and delayed wound closure concomitant to a higher actin stress fiber content and a slower turnover of actin filaments. Lastly, based on the expression analyses of microarray candidates, we suggest that dysregulated cell-matrix interactions and the ROCK kinase pathway might be key players in TSPC aging. Taken together, we propose that during tendon aging and degeneration, the TSPC pool is becoming exhausted in terms of size and functional fitness. Thus, our study provides the first fundamental basis for further exploration into the molecular mechanisms behind tendon aging and degeneration as well as for the selection of novel tendon-specific therapeutical targets. PMID:23826660
Kohler, Julia; Popov, Cvetan; Klotz, Barbara; Alberton, Paolo; Prall, Wolf Christian; Haasters, Florian; Müller-Deubert, Sigrid; Ebert, Regina; Klein-Hitpass, Ludger; Jakob, Franz; Schieker, Matthias; Docheva, Denitsa
Rotator Cuff Tendonitis; Bicipital Tendonitis; Subdeltoid Bursitis of the Shoulder; Subacromial Bursitis of the Shoulder; Medial Epicondylitis of the Elbow; Lateral Epicondylitis of the Elbow; DeQuervain's Tenosynovitis of the Wrist
...Inservice Inspection of Prestressed Concrete Containment Structures With Grouted Tendons...Inservice Inspection of Prestressed Concrete Containment Structures with Grouted Tendons...surveillance program for prestressed concrete containment structures with grouted...
The necessity of tendon interposition for the maintenance of joint space after basal joint resection arthroplasty with ligament reconstruction has not been established. A prospective, randomized study was performed. In Group I (nine patients), ligament reconstruction was performed to suspend the first metacarpal in addition to placement of a rolled tendon interposition to fill the void created by resection of the trapezium. In Group II (11 patients), ligament reconstruction alone was performed, with use of a Mitek suture anchor. No tendon interposition was performed. This allowed use of a more limited incision and shorter length of tendon graft. Average followup was 23 months. There was no difference between the two groups in range of motion of the thumb, grip strength, lateral pinch strength, the ability to perform activities of daily living, or subjective satisfaction with the procedure. Two- and three-point pinch strength was statistically significantly greater in Group II. Lateral radiographs of the basal joint at followup, at rest and with pinch, showed maintenance of the joint space, and no difference between the two groups. Tendon interposition is not necessary for maintenance of joint space after basal joint resection arthroplasty if ligament reconstruction is performed. PMID:9308523
Gerwin, M; Griffith, A; Weiland, A J; Hotchkiss, R N; McCormack, R R
Bovine and human tendon tissue do not induce calcification in vitro. However, extraction of those tissues with 3% Na2HPO4 converts them to calcifiable matrices. The supernatant fraction derived from the extraction contains a nondialyzable, perchloric acid soluble component that inhibits calcification of the extracted matrix. This inhibitory substance is characterized by a molecular weight in the range of 85,000-100,000. Exposure to pronase or hyaluronidase did not alter the inhibitory potency but did render the inhibitor dialyzable. Commercial sources of hyaluronic acid, chondrotitin-6-sulfate, chrondroitin-4-sulfate, dermatan sulfate, heparin and lysozyme did not inhibit calcification of the extracted matrix. Phosvitin, a phosphoglycoprotein is a potent inhibitor. Although phosvitin and the tendon extract also inhibit calcification of previously calcified matrix, they have no detectable effect on the rate of decalcification. We conclude that the mechanism of inhibition is characterized by a degree of specificity and that phosvitin and a macromolecular component of tendon tissue blocks conversion of an intermediate matrix-bound CaP complex to crystalline apatite. It seems reasonable that the tendon inhibitor could function in situ and possibly in vivo to control calcification of tendon tissue. PMID:667663
Quittner, C; Wadkins, C L
The assembly, deposition and organization of collagen fibril bundles and their composite fibrils were studied during morphogenesis of the chick embryo tendon using electron microscopy, serial sections and computer-assisted three-dimensional reconstruction techniques. The 14-day chick embryo is a stage when tendon architecture is being established and rapid changes in the mechanical properties occur between days 14 and 17 of development. Tendon matrix structure develops from discrete subunits, bundles of collagen fibrils. The bundles branch; undergo a gradual rotation over several micrometers; are intimately associated with the cellular elements of the developing tendon; and form arborizing networks within and among fascicles. The organization of discrete fibril segments into bundles, during the establishment of tendon architecture and function, where the segmental fibrillar components could interact with the interfibrillar matrix as well as with adjacent fibrils would contribute to the stabilization of this structure. The observed gradual rotation of the bundles would serve to stabilize the immature bundle through the physical twining of the composite fibrils while the extensive branching of the bundles observed at 14-days of development and their intimate association with the cellular elements would provide a higher order of structure stabilization. PMID:2612371
Birk, D E; Southern, J F; Zycband, E I; Fallon, J T; Trelstad, R L
Biological fixation of soft tissue-based grafts for anterior cruciate ligament (ACL) reconstruction poses a major clinical challenge. The ACL integrates with subchondral bone through a fibrocartilage enthesis, which serves to minimize stress concentrations and enables load transfer between two distinct tissue types. Functional integration thus requires the reestablishment of this fibrocartilage interface on reconstructed ACL grafts. We designed and characterized a novel mechanoactive scaffold based on a composite of poly-?-hydroxyester nanofibers and sintered microspheres; we then used the scaffold to test the hypothesis that scaffold-induced compression of tendon grafts would result in matrix remodeling and the expression of fibrocartilage interface-related markers. Histology coupled with confocal microscopy and biochemical assays were used to evaluate the effects of scaffold-induced compression on tendon matrix collagen distribution, cellularity, proteoglycan content, and gene expression over a 2-week period. Scaffold contraction resulted in over 15% compression of the patellar tendon graft and upregulated the expression of fibrocartilage-related markers such as Type II collagen, aggrecan, and transforming growth factor-?3 (TGF-?3). Additionally, proteoglycan content was higher in the compressed tendon group after 1 day. The data suggest the potential of a mechanoactive scaffold to promote the formation of an anatomic fibrocartilage enthesis on tendon-based ACL reconstruction grafts.
Spalazzi, Jeffrey P.; Vyner, Moira C.; Jacobs, Matthew T.; Moffat, Kristen L.
Objective: To describe the evaluation, diagnosis, and conservative treatment of a 31-year-old female recreational athlete with a snapping iliopsoas tendon. Background: The iliopsoas tendon has been implicated as an inflamed structure in this unique form of snapping hip. Hip pain, limitation of motion, or both may severely restrict vocational and recreational function and activities of daily living. Differential Diagnosis: Left snapping hip syndrome secondary to the iliopsoas tendon or the iliotibial band. Treatment: The treatment goal was to restore the athlete's pain-free, functional abilities. The primary focus of the treatment program was stretching of the left hip flexors. The patient demonstrated reduced pain and improved function following a 4-week stretching program and was fully functional and symptom free at 6 months. Uniqueness: Snapping hip syndrome is a clinical entity that may be described as hip pain associated with an audible snap of the hip during motion. The most common and well-known cause of this syndrome involves the snapping of the iliotibial band over the greater trochanter. A less common cause is the snapping of the iliopsoas tendon over the iliopectineal eminence. Conclusions: Understanding the anatomy and function of the iliopsoas tendon and related structures provides a basis for evaluation and treatment of this unique problem. ImagesFigure 1.Figure 2.
Keskula, Douglas R.; Lott, Jason; Duncan, Jewell B.
Chronic insertional tendinopathy of the Achilles tendon is a frequent and disabling pathologic entity. Operative treatment is indicated for patients for whom nonoperative management has failed. The treatment can consist of the complete detachment of the tendon insertion and extensive debridement. We biomechanically tested a new operative technique that uses buttons for fixation of the Achilles tendon insertion on the posterior calcaneal tuberosity and compared it with 2 standard bone anchor techniques. A total of 40 fresh-frozen cadaver specimens were used to compare 3 fixation techniques for reinserting the Achilles tendon: single row anchors, double row anchors, and buttons. The ultimate loads and failure mechanisms were recorded. The button assembly (median load 764 N, range 713 to 888) yielded a median fixation strength equal to 202% (range 137% to 251%) of that obtained with the double row anchors (median load 412 N, range 301 to 571) and 255% (range 213% to 317%) of that obtained with the single row anchors (median load 338 N, range 241 to 433N). The most common failure mechanisms were suture breakage with the buttons (55%) and pull out of the implant with the double row (70%) and single row (85%) anchors. The results of the present biomechanical cadaver study have shown that Achilles tendon reinsertion fixation using the button technique provides superior pull out strength than the bone anchors tested. PMID:24556479
Awogni, David; Chauvette, Guillaume; Lemieux, Marie-Line; Balg, Frédéric; Langelier, Ève; Allard, Jean-Pascal
A laboratory study was performed to evaluate the histopathological features of the macroscopically intact portion of the Achilles\\u000a tendon in patients undergoing surgery for an acute rupture of the Achilles tendon. Tendon samples were harvested from 29 individuals\\u000a (21 men, 8 women; mean age: 46 ± 12) who underwent repair of an Achilles tendon tear tear, and from 11 male patients who
Nicola MaffulliUmile; Umile Giuseppe Longo; Gayle D. Maffulli; Carla Rabitti; Anil Khanna; Vincenzo Denaro
Single-row, double-row, and transosseous equivalent techniques for isolated supraspinatus tendon tears with minimal atrophy: A retrospective comparative outcome and radiographic analysis at minimum 2-year followup
Purpose: The purpose of this study was to measure and compare the subjective, objective, and radiographic healing outcomes of single-row (SR), double-row (DR), and transosseous equivalent (TOE) suture techniques for arthroscopic rotator cuff repair. Materials and Methods: A retrospective comparative analysis of arthroscopic rotator cuff repairs by one surgeon from 2004 to 2010 at minimum 2-year followup was performed. Cohorts were matched for age, sex, and tear size. Subjective outcome variables included ASES, Constant, SST, UCLA, and SF-12 scores. Objective outcome variables included strength, active range of motion (ROM). Radiographic healing was assessed by magnetic resonance imaging (MRI). Statistical analysis was performed using analysis of variance (ANOVA), Mann — Whitney and Kruskal — Wallis tests with significance, and the Fisher exact probability test <0.05. Results: Sixty-three patients completed the study requirements (20 SR, 21 DR, 22 TOE). There was a clinically and statistically significant improvement in outcomes with all repair techniques (ASES mean improvement P = <0.0001). The mean final ASES scores were: SR 83; (SD 21.4); DR 87 (SD 18.2); TOE 87 (SD 13.2); (P = 0.73). There was a statistically significant improvement in strength for each repair technique (P < 0.001). There was no significant difference between techniques across all secondary outcome assessments: ASES improvement, Constant, SST, UCLA, SF-12, ROM, Strength, and MRI re-tear rates. There was a decrease in re-tear rates from single row (22%) to double-row (18%) to transosseous equivalent (11%); however, this difference was not statistically significant (P = 0.6). Conclusions: Compared to preoperatively, arthroscopic rotator cuff repair, using SR, DR, or TOE techniques, yielded a clinically and statistically significant improvement in subjective and objective outcomes at a minimum 2-year follow-up. Level of Evidence: Therapeutic level 3.
McCormick, Frank; Gupta, Anil; Bruce, Ben; Harris, Josh; Abrams, Geoff; Wilson, Hillary; Hussey, Kristen; Cole, Brian J.
In rare incidences of combined ruptures of the ACL and patellar tendon, either the patellar tendon ruptures or the associated ACL tear is often initially missed. Even when recognized, there is no established treatment regimen. We report a case of an intercollegiate football player with a combined rupture of the ACL and patellar tendon that was successfully treated by primary
Lydia A. Futch; William P. Garth; Greg J. Folsom; William K. Ogard
The authors present a case of a traumatic extensor hallucis longus tendon rupture sustained 2 days after hallux valgus and hammer toe correction. The ruptured tendon, separated by a 6-cm defect, was repaired using a fascia lata allograft. This case demonstrates a serious complication of a commonly performed procedure and a salvage technique useful for dealing with large tendon defects. PMID:12237269
Zielaskowski, Lorne A; Pontious, Jane
Most muscle stretching studies have focused on defin ing the biomechanical properties of isolated elements of the muscle-tendon unit or on comparing different stretching techniques. We developed an experimental model that was designed to evaluate clinically relevant biomechanical stretching properties in an entire muscle- tendon unit. Our objectives were to characterize the viscoelastic behavior of the muscle-tendon unit and to
Dean C. Taylor; James D. Dalton; Anthony V. Seaber; William E. Garrett
Magic angle magnetic resonance (MR) imaging consists of imaging tendons at 55° to the magnetic field. In people, magic angle MR imaging is valuable for detection of chronic tendon lesions and allows calculation of tendon T1 values. Increased T1 values occur in people with chronic tendinopathy. The T1 values of normal equine tendons have been reported but there are no available data for abnormal equine tendons. Twelve limbs were studied. Two limbs had diode laser tendon lesions induced postmortem, four limbs had diode laser tendon lesions induced in vivo and six limbs had naturally occurring tendon lesions. The limbs were imaged at 1.5 T using both conventional MR imaging and magic angle MR imaging. The post-mortem laser induced lesions were identified only with magic angle MR imaging. The in vivo induced lesions and naturally occurring lesions were identified with both techniques but had a different appearance with the two imaging techniques. Magic angle imaging was helpful at identifying lesions that were hypointense on conventional imaging. Increased T1 values were observed in all abnormal tendons and in several tendons with a subjectively normal MR appearance. The increased T1 value may reflect diffuse changes in the biochemical composition of tendons. Magic angle imaging has potential as a useful noninvasive tool to assess the changes of the extracellular tendon matrix using T1 values. PMID:22548673
Spriet, Mathieu; Murphy, Brian; Vallance, Stuart A; Vidal, Martin A; Whitcomb, Mary Beth; Wisner, Erik R
The distal attachments of the extensor hallucis longus (EHL) tendons in 47 amputated legs and in eight cadavers were examined. The EHL had two tendons in 34 of the amputated legs and bilaterally in five cadavers. The lateral tendon was inserted to the middle of the dorsal aspect of the base of the distal phalanx of the hallux and the
C. C. Denk; A. Öznur; H. S. Surucu
A simple modification of the catheter technique for retrieving flexor tendons is presented. The technique is based on the Seldinger principle. A flexible metal guide-wire is used to route a polythene catheter through the flexor tendon sheath, enabling tendon retrieval. PMID:8771486
Titley, O G
In the last few years, the effectiveness of cement grout in galvanized or polyethylene ducts, the most widely used corrosion protection system for multistrand bonded post-tensioned concrete tendons, has been under debate, due to significant tendon corrosion damage, several reported failures of individual tendons as well as a few collapses of non-typical structures. While experience in the USA has been
Ruben Mario Salas Pereira
This study evaluated the insertional anatomy and orientation of the biceps tuberosity and tendon to assess the anatomic validity of repairs made with 1 incision vs 2 incisions. Computed axial tomography was used to image 30 cadaver radii, and each tendon insertion was measured with a digital micrometer. Specimens were sectioned and imaged with Faxitron radiography (Faxitron X-Ray Corp, Wheeling, IL) to determine the angular orientation of the biceps tendon insertion relative to the tuberosity apex. The tuberosity axis of orientation averaged 65 degrees (range, 15 degrees -120 degrees ) of pronation from anterior, with angular orientation encompassing a mean 59 degrees (range, 15 degrees -100 degrees ) arc with the midpoint of the insertion averaging 50 degrees (range, -5 degrees to 105 degrees ). Most biceps tendons inserted on the anterior aspect of the apex of the tuberosity, with an average width of 7 mm and length of 22 mm. The biceps tuberosity is oriented in more pronation than is typically described, prohibiting anatomic reinsertion of the tendon in 35% of specimens with current single-incision techniques. PMID:18325797
Forthman, Christopher L; Zimmerman, Ryan M; Sullivan, Michael J; Gabel, Gerard T
Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a new disease associated with limited mouth opening that is often misdiagnosed as a temporomandibular disorder; subsequently, patients are mistakenly treated with irreversible operations. Due to the poor presentation and characterization of symptoms, the underlying pathological conditions remain unclear. We have previously conducted a proteomic analysis of tendons derived from one MMTAH subject and one facial deformity subject using two-dimensional fluorescence difference gel electrophoresis and liquid chromatography coupled with tandem mass spectrometry. However, the results were obtained for only one subject. The aim of the present study was to confirm the expression of specific molecules in tendon tissues from multiple subjects with MMTAH by applying two-dimensional polyacrylamide gel electrophoresis with matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Of the 19 proteins identified in tendons from both MMTAH and facial deformity patients, fibrinogen fragment D and beta-crystallin A4 were up-regulated, whereas myosin light chain 4 was down-regulated in MMTAH. We also found fibrinogen to be expressed robustly in tendon tissues of MMTAH patients. Our data provide the possibility that the distinctive expression of these novel proteins is associated with the pathology of MMTAH. PMID:23870541
Nakamoto, A; Sato, T; Hirosawa, N; Nakamoto, N; Enoki, Y; Chida, D; Usui, M; Takeda, S; Nagai, T; Sasaki, A; Sakamoto, Y; Yoda, T
Left ventricular (LV) false tendons are chordlike structures that traverse the LV cavity. They attach to the septum, to the papillary muscles, or to the free wall of the ventricle but not to the mitral valve. They are found in approximately half of human hearts examined at autopsy. Although it has been more than 100 years since their initial description, the functional significance of these structures remains largely unexplored. It has been suggested that they retard LV remodeling by tethering the walls to which they are attached, but there are few data to substantiate this. Some studies have suggested that false tendons reduce the severity of functional mitral regurgitation by stabilizing the position of the papillary muscles as the left ventricle enlarges. LV false tendons may also have deleterious effects and have been implicated in promoting membrane formation in discrete subaortic stenosis. This article reviews current understanding of the anatomy, echocardiographic characteristics, and pathophysiology of these structures. PMID:23602169
Silbiger, Jeffrey J
A total of 32 digits, including 3 thumbs, were reconstructed in an outpatient clinic. The patients were allowed to go home 3-4 hours after the operation. The patients had injury to the flexor tendon in no man's land without other complications except for an injury to the digital nerve in 6 cases. The tendon was reconstructed secondarily using a free graft. The minimum follow-up time was 6 months. The results were classified in three ways. With all methods the results, which were deemed satisfactory in 79% and poor in 21%, reached the average standard for this type of repair. Increasing age of the patients, injury to the pulley, preoperative adhesions, digital nerve injury, and time elapsed from injury to surgery impaired the results. This study indicates that tendon surgery of the hand with short postoperative care can also be conducted with satisfactory results in an outpatient clinic. PMID:4083778
Jaroma, H; Suomalainen, O; Sivula, U M; Turpeinen, L
A technique has been developed for the repair of Achilles tendon ruptures that allows for early mobilization of the patient. A Dacron vascular graft is woven from distal to proximal and across the site of the rupture in a Bunnell-type fashion. The patients are immobilized in a short-leg cast for two weeks and are then fitted for a posterior fiberglass splint. Seven patients with acute ruptures who were treated with repair with the Dacron graft were followed for a period ranging from ten to 38 months. They were allowed to return to their normal level of activity approximately five months after surgery. There have been no reruptures. This technique also holds particular promise for the late reconstruction of an Achilles tendon rupture as well as for the treatment of partial tears in the severely degenerated tendon. PMID:2970358
Lieberman, J R; Lozman, J; Czajka, J; Dougherty, J
Cell and matrix composites recently have been used to repair tendons and ligaments. In the current study the authors briefly review prior studies in this area, and the contributions these findings have made toward solving this clinical problem. The authors then provide a perspective on the necessary characteristics that the cells and delivery vehicles of these composites must possess, separately and in combination, to function successfully after surgery. The authors conclude by applying these functional tissue engineering principles to two tendon injury models in which mesenchymal stem cells have been suspended in Type I collagen gel to form composites for patellar and Achilles tendon repair. In the first study, mesenchymal stem cells were suspended in gel (5 million cells/mL) with no attempt to align the cells during incubation. The resulting composites were implanted in window defects in one patellar tendon in the rabbit knee, with gel alone in a matching defect on the contralateral side. Biomechanical evaluation at 4 weeks showed that the material properties of the mesenchy-mal stem cell based repairs were 18% to 33% greater than results for contralateral controls. In the second study, mesenchymal stem cells were suspended in gel (4 million cells/mL), contracted on a tensioned suture during incubation, placed in an Achilles gap defect, and compared with repairs of contralateral gap injuries containing suture alone (controls). By 4 weeks, the repairs treated with mesenchymal stem cells had achieved twice the structural properties of the contralateral controls and 50% to 60% of the stiffness and strength of normal tendons that were not surgically treated. In addition, the material properties of the repairs treated with mesenchymal stem cells had increased with time to 37% of normal by 12 weeks after surgery. Both studies reveal the benefits of using pluripotential cells in a collagen gel matrix, and suggest additional research that might enhance the repair quality of healing tendons. PMID:10546656
Butler, D L; Awad, H A
Surgical approaches to postoperative mediastinitis that imply wire removal achieve earlier infection recovery but leave the patient with sternal instability. In 10 patients after wound surgical debridement, my colleagues and I achieved sternal synthesis by using Achilles tendons retrieved from multiorgan donors and stored in glutaraldehyde. Three tendons were used in each patient; they were passed through the bone at the manubrium and parasternally at the midsternum and the lower sternum. Thirty-day computed tomographic scan results, infection recovery, and quality of life were satisfactory. PMID:15620987
De Feo, Marisa; Carozza, Antonio; Della Corte, Alessandro; Quarto, Cesare; Torella, Michele; De Santo, Luca Salvatore; Nappi, Gianantonio; Cotrufo, Maurizio
Proper replacement or repair of damaged tendons or ligaments requires functionally engineered tissue that mimics their native mechanical properties. While tendon structure–function relationships are generally assumed, there exists little quantitative evidence of the roles of distinct tendon components in tendon function. Previous work has used linear correlations to assess the independent, univariate effects of one structural or one biochemical variable
Paul S. Robinson; Tony W. Lin; Abbas F. Jawad; Renato V. Iozzo; Louis J. Soslowsky
A study of nutrition of various tendon graft preparations in adult chickens (up to 2 weeks after grafting), using tritiated proline and a trichloracetic acid extraction technique which separated the free and metabolized amino acid fractions, suggests that diffusion of nutrients is an important process in the initial nutrition of tendon grafts, that tendon grafts are metabolically active and viable structures, that adhesions which are frequently associated with tendon grafts do not appear to be essential to the nutrition of grafts, and that tendon grafts within fibrous pseudosheaths are nourished as effectively as grafts within synovial sheaths. PMID:512314
Manske, P R; Lesker, P A; Bridwell, K
Background: For arthroscopic anterior cruciate ligament reconstruction, the most commonly used graft constructs are either the hamstring tendon or patellar tendon. Well-controlled, long-term studies are needed to determine the differences between the 2 materials.Hypothesis: There is a difference between hamstring and patellar tendon grafts in the clinical results of anterior cruciate ligament reconstructions at 7 years.Study Design: Cohort study; Level
Justin Roe; Leo A. Pinczewski; Vivianne J. Russell; Lucy J. Salmon; Tomomaro Kawamata; Melvin Chew