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1

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

PubMed Central

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.; Drape, J.L.

2012-01-01

2

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

PubMed

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

2012-02-01

3

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

NASA Astrophysics Data System (ADS)

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.

2008-02-01

4

Fiber distribution in a 3D FEM Model of the Supraspinatus Tendon  

E-print Network

Fiber distribution in a 3D FEM Model of the Supraspinatus Tendon Author: Romy Hasler Supervisors, the tendon's fiber were computed and the material was defined in the fiber direction and in the transverse and therefore is softer in the fiber direction and stronger in the transverse direction. The isotropic model

Dalang, Robert C.

5

Supraspinatus tendon and subacromial space parameters measured on ultrasonographic imaging in subacromial impingement syndrome.  

PubMed

PURPOSE: To characterize the supraspinatus tendon thickness, subacromial space, and the relationship between tendon thickness and subacromial space to further elucidate the mechanisms of subacromial impingement syndrome. METHODS: In a single-blind cross-sectional study, subjects were recruited with subacromial impingement syndrome (n = 20) and asymptomatic controls (n = 20) matched for age, gender, and hand dominance. Ultrasound images were collected using a 4-12-MHz linear transducer in B-mode of the supraspinatus tendon in the transverse (short axis) and the anterior aspect of the subacromial space outlet. Using image callipers, measurements of tendon thickness were taken at 3 points along the tendon and averaged for a single thickness measure. The subacromial space outlet was measured via the acromiohumeral distance (AHD) defined by the inferior acromion and superior humeral head. The occupation ratio was calculated as the tendon thickness as a percentage of AHD. RESULTS: The subacromial impingement syndrome group had a significantly thicker tendon (mean difference = 0.6 mm, p = 0.048) and a greater tendon occupation ratio (mean difference = 7.5 %, p = 0.014) compared to matched controls. There were no AHD group differences. CONCLUSIONS: The supraspinatus tendon was thicker and occupied a greater percentage of AHD, supporting an intrinsic mechanism. An extrinsic mechanism of tendon compression is theoretically supported, but future imaging studies need to confirm direct compression with elevation. Treatment to reduce tendon thickness may reduce symptoms, and surgical intervention to increase subacromial space may be considered if tendon compression can be verified. PMID:23736252

Michener, Lori A; Subasi Yesilyaprak, Sevgi S; Seitz, Amee L; Timmons, Mark K; Walsworth, Matthew K

2013-06-01

6

Arthroscopic Repair of Full-Thickness Tears of the Supraspinatus: Does the Tendon Really Heal?  

Microsoft Academic Search

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

7

Arthroscopic Intratendinous Repair of the Delaminated Partial-Thickness Rotator Cuff Tear in Overhead Athletes  

Microsoft Academic Search

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

2008-01-01

8

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

PubMed

Supraspinatus (SS) tendon tears are common musculoskeletal injuries whose surgical repair exhibits the highest incidence of re-tear of any tendon. Development of therapeutics for improving SS tendon healing is impaired by the lack of a model that allows biological perturbations to identify mechanisms that underlie ineffective healing. The objective of this study was to develop a mouse model of supraspinatus insertion site healing by creating a reproducible SS tendon detachment and surgical repair which can be applied to a wide array of inbred mouse strains and genetic mutants. Anatomical and structural analyses confirmed that the rotator cuff of the mouse is similar to that of human, including the presence of a coracoacromial (CA) arch and an insertion site that exhibits a fibrocartilagenous transition zone. The surgical repair was successfully conducted on seven strains of mice that are commonly used in Orthopaedic Research suggesting that the procedure can be applied to most inbred strains and genetic mutants. The quality of the repair was confirmed with histology through 14 days after surgery in two mouse strains that represent the variation in mouse strains evaluated. The developed mouse model will allow us to investigate mechanisms involved in insertion site healing. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:25-32, 2015. PMID:25231092

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

2015-01-01

9

Expression of Atrophy mRNA Relates to Tendon Tear Size in Supraspinatus Muscle  

PubMed Central

Skeletal muscle atrophy and fatty infiltration develop after tendon tearing. The extent of atrophy serves as one prognostic factor for the outcome of surgical repair of rotator cuff tendon tears. We asked whether mRNA of genes involved in regulation of degradative processes leading to muscle atrophy, ie, FOXOs, MSTN, calpains, cathepsins, and transcripts of the ubiquitin-proteasome pathway, are overexpressed in the supraspinatus muscle in patients with and without rotator cuff tears. We evaluated biopsy specimens collected during surgery of 53 consecutive patients with different sizes of rotator cuff tendon tears and six without tears. The levels of corresponding gene transcripts in total RNA extracts were assessed by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Supraspinatus muscle atrophy was assessed by MRI. The area of muscle tissue (or atrophy), decreased (increased) with increasing tendon tear size. The transcripts of CAPN1, UBE2B, and UBE3A were upregulated more than twofold in massive rotator cuff tears as opposed to smaller tears or patients without tears. These atrophy gene products may be involved in cellular processes that impair functional recovery of affected muscles after surgical rotator cuff repair. However, the damaging effects of gene products in their respective proteolytic processes on muscle structures and proteins remains to be investigated. PMID:18941855

Schmutz, Silvia; Fuchs, Thomas; Regenfelder, Felix; Steinmann, Patrick; Zumstein, M.

2008-01-01

10

Supraspinatus tears: Propagation and strain alteration  

Microsoft Academic Search

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

2003-01-01

11

Quantitative Ultrasound Facilitates the Exploration of Morphological Association of the Long Head Biceps Tendon with Supraspinatus Tendon Full Thickness Tear  

PubMed Central

Backgrounds Pathology of the long head biceps tendon (LHBT) is associated with rotator cuff tears but whether the LHBT texture changes following supraspinatus tendon full thickness tear (SSFT) can be detected at the extra-articular segment remains unknown. This cross-sectional study aimed to explore the morphological differences of the LHBT in shoulders with and without deficient rotator cuffs by using quantitative ultrasound. Materials and Methods We selected 145 cases with SSFT and 145 age-and- gender-matched controls. The width, thickness, flattening ratio, cross-sectional area, and echogenicity ratio of the LHBT were measured and a general linear model was used to clarify the relationship between rotator cuff pathology and LHBT morphology. The receiver operating characteristic curves of each parameter were constructed for SSFT discrimination and the maximal Youden indexes were used to define the best cut-off points. Results We found increased thickness and cross-sectional area but decreased flattening ratio in shoulders with SSFT, and no between-group differences in the width and echogenicity ratio. The LHBT appearance was modified by biceps peritendinous effusion and medial subluxation, but not by the size of SSFT. The flattening ratio was the best discriminator for SSFT with an area under curve of 0.81 (95% confidence interval, 0.76–0.86). The cut-off values to differentiate between the non-tear and tear groups were 2.00 mm of the thickness, 1.73 of the flattening ratio and 10.53 mm2 of the cross-sectional area. Conclusion Quantitative ultrasound facilitated the detection of the LHBT morphological changes following SSFT and demonstrated its potential utility in discriminating rotator cuff deficiency. PMID:25412357

Chang, Ke-Vin; Chen, Wen-Shiang; Wang, Tyng-Guey; Hung, Chen-Yu; Chien, Kuo-Liong

2014-01-01

12

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

PubMed Central

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

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

2013-01-01

13

Classification of the degenerative grade of lesions of supraspinatus rotator cuff tendons by FT-Raman spectroscopy  

NASA Astrophysics Data System (ADS)

FT-Raman spectroscopy was employed to access the biochemical alterations occurring on the degenerative process of the rotator cuff supraspinatus tendons. The spectral characteristic variations in the 351 spectra of samples of 39 patients were identified with the help of Principal Components Analysis. The main variations occurred in the 840-911; 1022- 1218; 1257; 1270; 1300; 1452; 1663; and 1751 cm -1 regions corresponding to the vibrational bands of proline, hydroxiproline, lipids, nucleic acids, carbohydrates, collagen, and elastin. These alterations are compatible with the pathology alterations reported on the literature. Scattering plots of PC 4 vs PC 2 and PC 3 vs PC 2 contrasted with histopathological analysis has enabled the spectral classification of the data into normal and degenerated groups of tendons. By depicting empiric lines the estimated sensibility and specificity were 39,6 % and 97,8 %, respectively for PC 4 vs PC 2 and 36,0 % and 100 %, respectively for PC 3 vs PC 2. These results indicate that Raman spectroscopy can be used to probe the general tendon quality and could be applied as co adjuvant element in the usual arthroscopy surgery apparatus to guide the procedure and possibly infer about the probability of rerupture.

Palma Fogazza, Bianca; da Silva Carvalho, Carolina; Godoy Penteado, Sergio; Meneses, Cláudio S.; Abrahão Martin, Airton; da Silva Martinho, Herculano

2007-02-01

14

Characterizing Local Collagen Fiber Re-Alignment and Crimp Behavior Throughout Mechanical Testing in a Mature Mouse Supraspinatus Tendon Model  

PubMed Central

Background Collagen fiber re-alignment and uncrimping are two postulated mechanisms of tendon structural response to load. Recent studies have examined structural changes in response to mechanical testing in a postnatal development mouse supraspinatus tendon model (SST), however, those changes in the mature mouse have not been characterized. The objective of this study was to characterize collagen fiber realignment and crimp behavior throughout mechanical testing in a mature mouse SST. Method of Approach A tensile mechanical testing set-up integrated with a polarized light system was utilized for alignment and mechanical analysis. Local collagen fiber crimp frequency was quantified immediately following the designated loading protocol using a traditional tensile set up and a flash-freezing method. The effect of number of preconditioning cycles on collagen fiber re-alignment, crimp frequency and mechanical properties in midsubstance and insertion site locations were examined. Results Decreases in collagen fiber crimp frequency were identified at the toe-region of the mechanical test at both locations. The insertion site re-aligned throughout the entire test, while the midsubstance re-aligned during preconditioning and the test’s linear-region. The insertion site demonstrated a more disorganized collagen fiber distribution, lower mechanical properties and a higher cross-sectional area compared to the midsubstance location. Conclusions Local collagen fiber re-alignment, crimp behavior and mechanical properties were characterized in a mature mouse SST model. The insertion site and midsubstance respond differently to mechanical load and have different mechanisms of structural response. Additionally, results support that collagen fiber crimp is a physiologic phenomenon that may explain the mechanical test toe-region. PMID:22776688

Miller, Kristin S.; Connizzo, Brianne K.; Feeney, Elizabeth; Soslowsky, Louis J.

2012-01-01

15

Tissue characteristics in tendon-to-bone healing change after rotator cuff repair using botulinumneurotoxin A for temporary paralysis of the supraspinatus muscle in rats.  

PubMed

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

2014-04-01

16

Supraspinatus tears: propagation and strain alteration.  

PubMed

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

2003-01-01

17

Arthroscopic intratendinous repair of the delaminated partial-thickness rotator cuff tear in overhead athletes.  

PubMed

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

2008-08-01

18

Possible involvement of IGF-1 signaling on compensatory growth of the infraspinatus muscle induced by the supraspinatus tendon detachment of rat shoulder  

PubMed Central

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. PMID:24744876

Ichinose, Tsuyoshi; Lesmana, Ronny; Yamamoto, Atsushi; Kobayashi, Tsutomu; Shitara, Hitoshi; Shimoyama, Daisuke; Takatsuru, Yusuke; Iwasaki, Toshiharu; Shimokawa, Noriaki; Takagishi, Kenji; Koibuchi, Noriyuki

2014-01-01

19

Infraspinatus delamination does not affect supraspinatus tear repair.  

PubMed

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

2007-05-01

20

The behavior of rotator cuff tendon cells in three-dimensional culture  

E-print Network

The rotator cuff is composed of the supraspinatus, infraspinatus, subcapularis, and teres minor tendons. Rotator cuff injuries are common athletic and occupational injuries that surgery cannot fully repair. Therefore tendon ...

Gill, Harmeet (Harmeet Kaur)

2007-01-01

21

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

Microsoft Academic Search

OBJECTIVES--To analyse the glycosaminoglycans of the adult human rotator cuff tendon matrix, to characterise changes in the glycosaminoglycan composition with age and in chronic rotator cuff tendinitis. METHODS--Rotator cuff (supraspinatus) tendons (n = 84) and common biceps tendons (n = 26) were obtained from cadavers with no history of tendon pathology (age range 11-95 years). Biopsies of rotator cuff tendons

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

1994-01-01

22

Partial-thickness tears of the rotator cuff  

Microsoft Academic Search

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

1996-01-01

23

Innervation pattern of the suprascapular nerve within supraspinatus: a three-dimensional computer modeling study.  

PubMed

The relationship between the innervation pattern of the suprascapular nerve (SSN) and the muscle architecture of supraspinatus has not been thoroughly investigated. The supraspinatus is composed of two architecturally distinct regions: anterior and posterior. Each of these regions is further subdivided into three parts: superficial, middle and deep. The purpose of this study was to investigate the course of the SSN throughout the volume of supraspinatus and to relate the intramuscular branches to the distinct regions and parts of the supraspinatus. The SSN was dissected in thirty formalin embalmed cadaveric specimens and digitized throughout the muscle volume in six of those specimens. The digitized data were modeled using Autodesk(®) Maya(®) 2011. The three-dimensional (3D) models were used to relate the intramuscular innervation pattern to the muscle and tendon architecture defined by Kim et al. (2007, Clin Anat 20:648-655). The SSN bifurcated into two main trunks: medial and lateral. All parts of the anterior region were predominantly innervated by the medial trunk and its proximal and medial branches, whereas all parts of the posterior region predominantly by the lateral trunk and its posterolateral and/or posteromedial branches. The posterior region also received innervation from the proximal branch of the medial trunk in half of the specimens. These findings provide evidence that the anterior and posterior regions are distinct with respect to their innervation. The 3D map of the innervation pattern will aid in planning future clinical studies investigating muscle activation patterns and provide insight into possible injury of the nerve with supraspinatus pathology and surgical techniques. PMID:23649406

Hermenegildo, J A; Roberts, S L; Kim, S Y

2014-05-01

24

Arthroscopic treatment of calcific tendonitis.  

PubMed

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

2014-04-01

25

Development of a porcine deep partial thickness burn model.  

PubMed

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

2013-03-01

26

Effects of selective paralysis of the supraspinatus muscle using botulinum neurotoxin a in rotator cuff healing in rats.  

PubMed

We hypothesized that a temporary rotator cuff paralysis using botulinum-neurotoxin A (BoNtA) would lead to an improved tendon-to-bone healing after repair of supraspinatus lesions. One hundred sixty Sprague-Dawley rats were randomly assigned to either the BoNtA or the control (saline) group. BoNtA/saline-solution was injected into the supraspinatus muscle 1 week prior to surgery. A supraspinatus defect was made; we distinguished between a lesion with normal and increased repair load. Furthermore, one subgroup had the operated shoulder immobilized in a cast. Histologic analysis and biomechanical testing followed. Specimens from the BoNtA-group, which were treated with an increased repair load, showed less cellularity and more organization in the interface tissue compared to the saline control group. In addition, we found that the collagen 1-3 quotient in the BoNtA specimen was significantly (p?=?0.0051) higher than in the control group. Ultimate load at failure between the groups was not significantly different (p?>?0.05). We did not observe any significant differences between the mobilized and immobilized specimen (p?=?0.2079). The study shows that tendon-to-bone healing after rotator cuff repair can be altered positively using BoNtA pre-operatively. Tears with increased repair load seem to benefit the most-at least histologically. PMID:23239559

Ficklscherer, Andreas; Hartl, Tessa-Katharina; Scharf, Markus; Sievers, Birte; Schröder, Christian; Milz, Stefan; Niethammer, Thomas; Pietschmann, Matthias F; Müller, Peter E

2013-05-01

27

Transtendon rotator-cuff repair of partial-thickness articular surface tears can lead to medial rotator-cuff failure  

PubMed Central

Purpose The purpose of this study was to evaluate clinical and anatomic outcomes of patients following transtendon rotator-cuff repair of partial articular supraspinatus tendon avulsion (PASTA) lesions. Patients and methods Patients in the senior author’s practice who had isolated PASTA lesions treated by transtendon rotator-cuff repair were included (n=8) and retrospectively reviewed. All patients were evaluated preoperatively and at a mean of 21.2 months (±9.7 months) postoperatively using standardized clinical evaluation (physical exam, American Shoulder and Elbow Surgeons, and Simple Shoulder Test). All patients underwent postoperative imaging with a magnetic resonance imaging arthrogram. Results There was a significant improvement in American Shoulder and Elbow Surgeons (42.7±17.5 to 86.9±25.2) and Simple Shoulder Test (4.6±3.2 to 10.1±3.8) scores from pre- to postoperative, respectively. Postoperative imaging demonstrated full-thickness medial cuff tearing in seven patients, and one patient with a persistent partial articular surface defect. Conclusion Transtendon repair of PASTA lesions may lead to improvements in clinical outcome. However, postoperative imaging demonstrated a high incidence of full-thickness rotator-cuff defects following repair. PMID:25114604

Woods, Tom C; Carroll, Michael J; Nelson, Atiba A; More, Kristie D; Berdusco, Randa; Sohmer, Stephen; Boorman, Richard S; Lo, Ian KY

2014-01-01

28

Matrix metalloproteases and their inhibitors are altered in torn rotator cuff tendons, but also in the macroscopically and histologically intact portion of those tendons  

PubMed Central

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. PMID:24367772

Castagna, Alessandro; Cesari, Eugenio; Garofalo, Raffaele; Gigante, Antonio; Conti, Marco; Markopoulos, Nikolaos; Maffulli, Nicola

2013-01-01

29

The efficacy of ultrasound in the diagnosis of long head of the biceps tendon pathology.  

PubMed

The use of shoulder ultrasound as an imaging modality has recently gained widespread attention; however, the ability of ultrasound to diagnose long head of the biceps tendon pathology accurately still remains unclear. The biceps tendons in 71 patients were prospectively evaluated by comparison of standard ultrasonographic and arthroscopic examinations. Arthroscopic examination was used as the gold standard comparison. Ultrasound showed a 100% specificity and 96% sensitivity for subluxation or dislocation. Ultrasound detected all complete ruptures of the biceps tendon but detected none of the 23 partial-thickness tears. Overall, ultrasound diagnosed 35 of 36 normal biceps tendons (specificity, 97%) and 17 of 35 abnormal biceps tendons (sensitivity, 49%). Ultrasound can reliably diagnose complete rupture, subluxation, or dislocation of the biceps tendon. It is not reliable for detecting intraarticular partial-thickness tears. PMID:16414462

Armstrong, April; Teefey, Sharlene A; Wu, Thomas; Clark, Aileen M; Middleton, William D; Yamaguchi, Ken; Galatz, Leesa M

2006-01-01

30

Preservation methods of allografts and their (lack of) influence on clinical results in partial thickness burns.  

PubMed

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

2011-08-01

31

Partial-thickness Articular Surface Rotator Cuff Tears: An All-inside Repair Technique  

Microsoft Academic Search

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

2010-01-01

32

Current concepts in the management of tendon disorders.  

PubMed

Primary disorders of tendons are common and constitute a high proportion of referrals to rheumatologists. Certain tendons are particularly vulnerable to degenerative pathology; these include the Achilles, patella, elements of the rotator cuff, forearm extensors, biceps brachi and tibialis posterior tendons. Disorders of these tendons are often chronic and can be difficult to manage successfully in the long term. Significant advances have been made in understanding the pathophysiology of these conditions. Histopathological evidence, together with advances in imaging techniques, has made us more appreciative of the degenerative (rather that inflammatory) nature of these conditions. Additionally the presence of neovascularization is now well-recognized in long-standing tendinopathy. We review the mechanical, vascular and developing neural theories that attempt to explain the aetiology of degenerative tendinopathy. We also explore theories of why specific tendons (such as the Achilles and supraspinatus tendons) are particularly prone to degenerative pathology. Traditionally, treatments have placed a heavy emphasis on anti-inflammatory strategies, which are often inappropriate. Recently, however, significant advances in the practical management of tendon disorders have been made. In particular the advent of 'eccentric loading' training programmes has revolutionized the treatment of Achilles tendinopathy in some patients. This concept is currently being extended to include other commonly injured tendons. Other current treatments are reviewed, as are potential future treatments. PMID:16490749

Rees, J D; Wilson, A M; Wolman, R L

2006-05-01

33

Nonoperative treatment of partial-thickness meniscal tears identified during anterior cruciate ligament reconstruction.  

PubMed

The reported incidence and treatment of partial-thickness meniscal tears seen at anterior cruciate ligament (ACL) reconstruction varies widely. The success of nonoperative treatment of partial meniscal tears identified during ACL reconstruction at our institution was reviewed. All incomplete meniscal tears were treated with observation, all full-thickness tears were treated with repair or partial meniscectomy. Partial tears of the lateral meniscus were noted three times more commonly than in the medial meniscus and were seen more acutely after ACL injury than full-thickness tears. At 2-year follow-up, excellent knee function was noted when these tears were treated nonoperatively. PMID:15315046

Zemanovic, Jason R; McAllister, David R; Hame, Sharon L

2004-07-01

34

The effect of medical exercise therapy on a patient with chronic supraspinatus tendinitis. Diagnostic ultrasound--tissue regeneration: a case study.  

PubMed

There is an increased focus on the importance of using active exercise regimes for treating dysfunction in the musculoskeletal system. However, we have little exact knowledge on how to dose and grade exercises or the effect of exercise on the regeneration of low metabolic tissue structures in vivo. This case study deals with both topics and emphasizes the use of exercise only when treating a 73-year-old patient with a 1-year history of shoulder pain. His evaluation indicated chronic supraspinatus syndrome. Different treatment methods had no effect, and medical exercise therapy was tried as a last resort. The patient recovered after 21/2 months with four treatments per week. Diagnostic ultrasound taken before treatment and after a 51/2-month period showed that the supraspinatus tendon had regenerated. These findings are encouraging, supporting the possibility of tendon repair with biomechanical stresses from exercise. To our knowledge, it has never been shown in vivo that it is possible for a low metabolic structure to regenerate using exercise only. Instead of having surgery with an uncertain outcome, today the patient is free of symptoms and living a normal life enjoying his sporting activities nearly 4 years after he finished the treatment. PMID:7849752

Torstensen, T A; Meen, H D; Stiris, M

1994-12-01

35

Optimal treatment of partial thickness burns in children: a systematic review.  

PubMed

A large part of the patient population of a burn centre consists of children, most of whom are younger than four years. The majority of these young children suffer from superficial and deep partial thickness scald burns that may easily deepen to full thickness burns. A proper wound therapy, that prevents infection and ensures a moist wound condition, might prevent the deterioration of the wound. Therefore, we performed a systematic review of wound management and dressing materials to select the best treatment option for children with burns. A search in Medline and Embase revealed 51 articles for a critical appraisal. The articles were divided into randomized controlled trials, cohort studies and a group of case-reports. Total appraisal did not differ much amongst the groups; the level of evidence was highest in the randomized controlled trials and lowest in the case-reports. In 16 out of 34 comparative studies, silver sulfadiazine or a silver sulfadiazine/chlorhexidine-gluconate combination was the standard of wound care treatment. The competitor dressing was Biobrane(®) in six studies and amnion membrane in three. Tulle gauze, or tulle gauze impregnated with an antibacterial addition were the standard of care treatment in seven studies. In general, membranous dressings like Biobrane(®) and amnion membrane performed better than the standard of care on epithelialization rate, length of hospital stay and pain for treatment of partial thickness burns in children. However, hardly any of the studies investigated long-term results like scar formation. PMID:24290852

Vloemans, A F P M; Hermans, M H E; van der Wal, M B A; Liebregts, J; Middelkoop, E

2014-03-01

36

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

SciTech Connect

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

Satoh, Yasushi [Department of Biochemistry, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan)], E-mail: ys@ndmc.ac.jp; Saitoh, Daizoh [Division of Traumatology, Research Institute, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Takeuchi, Atsuya; Ojima, Kenichiro; Kouzu, Keita; Kawakami, Saki [Department of Biochemistry, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Ito, Masataka [Department of Developmental Anatomy and Regenerative Biology, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Ishihara, Masayuki [Division of Biomedical Engineering, Research Institute, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Sato, Shunichi [Division of Biomedical Information Science, Research Institute, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Takishima, Kunio [Department of Biochemistry, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan)

2009-03-27

37

Achilles Tendonitis  

MedlinePLUS

... strong as they can be. Strong, flexible muscles work more efficiently and put less stress on your tendon. Increase the intensity and length ... as much as possible. Vary your exercise routine. Work different muscle ... or doing activities that put stress on your feet. Wait until all the pain ...

38

Mineral Distributions at the Developing Tendon Enthesis  

PubMed Central

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. PMID:23152788

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

2012-01-01

39

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

PubMed Central

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

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

2010-01-01

40

The effect of moist and moist exposed dressings on healing and barrier function restoration of partial thickness wounds  

Microsoft Academic Search

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

2003-01-01

41

Effect of Extracorporeal Shock Wave Treatment on Deep Partial-Thickness Burn Injury in Rats: A Pilot Study  

PubMed Central

Extracorporeal shock wave therapy (ESWT) enhances tissue vascularization and neoangiogenesis. Recent animal studies showed improved soft tissue regeneration using ESWT. In most cases, deep partial-thickness burns require skin grafting; the outcome is often unsatisfactory in function and aesthetic appearance. The aim of this study was to demonstrate the effect of ESWT on skin regeneration after deep partial-thickness burns. Under general anesthesia, two standardized deep partial-thickness burns were induced on the back of 30 male Wistar rats. Immediately after the burn, ESWT was given to rats of group 1 (N = 15), but not to group 2 (N = 15). On days 5, 10, and 15, five rats of each group were analyzed. Reepithelialization rate was defined, perfusion units were measured, and histological analysis was performed. Digital photography was used for visual documentation. A wound score system was used. ESWT enhanced the percentage of wound closure in group 1 as compared to group 2 (P < 0.05). The reepithelialization rate was improved significantly on day 15 (P < 0.05). The wound score showed a significant increase in the ESWT group. ESWT improves skin regeneration of deep partial-thickness burns in rats. It may be a suitable and cost effective treatment alternative in this type of burn wounds in the future.

Kamelger, Florian Stefan; Jeschke, Johannes; Piza-Katzer, Hildegunde

2014-01-01

42

Effect of timing of surgical SSP tendon repair on muscle alterations.  

PubMed

To investigate the impacts of delayed repairs of a supraspinatus tendon tear on the supraspinatus muscle, we used an animal model data from two previously published studies in which one supraspinatus (SSP) tendon was detached. In one cohort, the rabbits were killed in groups of 10 at 4, 8, and 12?weeks. In the other cohort, a repair was done at these time points, 12 rabbits each, and the animals killed were 12 weeks later. SSP fossa volume (Muscle belly plus extramuscular fat [e-fat] volume), percentage of intramuscular fat (i-fat), and muscle tissue volume (muscle belly volume minus i-fat), as well as CT determination of e-fat and i-fat of both cohorts, were compared. Fossa volume increased (p??0.05), but early repair prevented further volume losses, a fact not seen after 8 and 12?weeks delay of repair. No reversal of e-fat or of i-fat occurred, in fact i-fat almost doubled after 4?weeks delay of repair (p?

Uhthoff, Hans K; Coletta, Elizabeth; Trudel, Guy

2014-11-01

43

Muscle loading is necessary for the formation of a functional tendon enthesis  

PubMed Central

Muscle forces are essential for skeletal patterning during development. Eliminating muscle forces, e.g., through paralysis, leads to bone and joint deformities. Botulinum toxin (BtxA)-induced paralysis of mouse rotator cuffs throughout postnatal development closely mimics neonatal brachial plexus palsy, a significant clinical condition in infants. In these mice, the tendon-to-bone attachment (i.e., the tendon enthesis) presents defects in mineral accumulation and fibrocartilage formation, presumably impairing the function of the tissue. The objective of the current study was to investigate the functional consequences of muscle unloading using BtxA on the developing supraspinatus tendon enthesis. We found that the maximum endurable load and stiffness of the supraspinatus tendon attachment decreased after four and eight weeks of post-natal BtxA-muscle unloading relative to controls. Tendon cross-sectional area was significantly reduced by BtxA-unloading, suggesting that the reduction of mechanical function resulted in part from geometric changes. However, strength, modulus, and toughness were also decreased in the BtxA-unloaded group compared to controls, indicating a decrease in tissue quality. Polarized-light microscopy and Raman microprobe analysis were used to determine collagen fiber alignment and mineral characteristics, respectively, in the tendon enthesis that might contribute to the reduced biomechanical performance in BtxA-unloaded shoulders. Collagen fiber alignment was significantly reduced in BtxA-unloaded shoulders. The mineral-to-matrix ratio in mineralized fibrocartilage was not affected by loading. However, the crystallographic atomic order of the hydroxylapatite phase (a measure of crystallinity) was reduced and the amount of carbonate (substituting for phosphate) in the hydroxylapatite crystals was increased. Taken together, these micrometer-scale structural and compositional changes partly explain the observed decreases in the mechanical functionality of the tendon enthesis in the absence of muscle loading. PMID:23542869

Schwartz, AG; Lipner, JH; Pasteris, JD; Genin, GM; Thomopoulos, S

2013-01-01

44

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

NASA Astrophysics Data System (ADS)

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

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

2007-02-01

45

Lateral Patellofemoral Ligament Reconstruction Using a Quadriceps Tendon Graft  

PubMed Central

Medial patellar subluxation (MPS) is normally described after a lateral retinacular release. However, isolated MPS in the absence of a previous lateral release does occur. This type of patellar instability is often overlooked, and a high index of suspicion is needed for appropriate diagnosis and treatment. This report describes a technique developed in response to episodes of isolated MPS. The technique uses a partial-thickness graft from the quadriceps tendon to reconstruct the lateral patellofemoral ligament and provide stability to the lateral side of the patella.

Saper, Michael G.; Shneider, David A.

2014-01-01

46

A prospective, randomized trial of silver containing hydrofiber dressing versus 1% silver sulfadiazine for the treatment of partial thickness burns.  

PubMed

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

2010-08-01

47

Tendon Transfer Surgery  

MedlinePLUS

... in hand function occurs. The muscle imbalance or muscle loss due to nervous system disease may be treated with tendon transfers. Common nervous system disorders treated with tendon ... muscle atrophy. Finally, there are some conditions in which ...

48

Extensor Tendon Injuries  

MedlinePLUS

... these small-muscle tendons that allow delicate finger motions and coordination. CAUSES Extensor tendons are just under ... a splint with slings that allows some finger motion, may be used for injuries of this kind. ...

49

Randomized clinical study of Hydrofiber dressing with silver or silver sulfadiazine in the management of partial-thickness burns.  

PubMed

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

2006-01-01

50

Overload and neovascularization of shoulder tendons in volleyball players  

PubMed Central

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

2012-01-01

51

The role of transforming growth factor beta isoforms in tendon-to-bone healing.  

PubMed

The purpose of this study was to examine the role of two of the three transforming growth factor beta (TGF-?) isoforms at the healing tendon-to-bone insertion. The supraspinatus tendons of 64 rats were transected at their bony insertions and repaired to the humeral head. One shoulder of each rat received an osmotic pump for sustained delivery of the following factors at the repair site: (1) TGF-?1 and neutralizing antibodies to TGF-?2 and 3 (TGF-?1 group), (2) TGF-?3 and neutralizing antibodies to TGF-?1 and 2 (TGF-?3 group), (3) neutralizing antibodies to TGF-?1, 2, and 3 (anti-TGF-? group), and (4) saline (saline group). The contralateral shoulders received saline to serve as paired controls. The repairs were evaluated at multiple time points postmortem using histology-based assays and biomechanical testing. Treated shoulders in the TGF-?1 group showed increased type III collagen production compared to the paired control shoulders, indicative of a scar-mediated response. There was a trend toward reduced mechanical properties in the TGF-?1 group, but these changes did not reach statistical significance. The anti-TGF-? group showed no difference in tissue volume, but significantly inferior mechanical properties, compared to the paired control shoulders. The TGF-?3 group did not show any differences compared to the paired control shoulders. Although TGF-? isoforms play important roles in tendon-to-bone development and healing, application of exogenous TGF-? isoforms and neutralizing antibodies to the subacromial space using osmotic pumps did not improve supraspinatus tendon-to-bone healing. PMID:20615095

Kim, H Mike; Galatz, Leesa M; Das, Rosalina; Havlioglu, Necat; Rothermich, Stefan Y; Thomopoulos, Stavros

2011-04-01

52

Single-detector polarization-sensitive optical coherence tomography for assessment of rotator cuff tendon integrity.  

PubMed

This preliminary study assessed trimmed supraspinatus tendons from rotator cuff repairs (RCRs) to compare the samples' surgically cut ends and torn ends with histopathology and polarization-sensitive optical coherence tomography (PS-OCT) imaging. PS-OCT can be used to assess collagen content and organization in birefringent tissue and shows promise in RCR. The data were compared to determine correlations between luminosity measured from histopathology and PS-OCT. Bivariate plots and a simple regression were performed to assess the linearity of the 2 groups, with a predictive value of less than .05 showing significant correlation. Approximately 50% of the visually inspected supraspinatus tendons acceptable for RCR exhibited collagen depletion when examined by histopathology, compared with PS-OCT. Because a strong correlation in collagen concentrations existed between histopathology and PS-OCT polarized back-reflection intensity, this study established the potential of PS-OCT for clinical use in the assessment of collagen content and organization to improving outcomes in RCR. PMID:22900245

Rashidifard, Christopher; Martin, Scott; Kumar, Namita; Azimi, Ehsan; Liu, Bin; Brezinski, Mark E

2012-08-01

53

Bipolar infrapatellar tendon rupture.  

PubMed

Traumatic patella alta in children occurs either distal to the patellar tendon as a tibial tubercle apophyseal fracture or proximally as an osteochondral sleeve fracture of the inferior patellar pole. Acute surgical exploration in a pediatric case of a knee extensor mechanism rupture revealed both proximal and distal (bipolar) patellar tendon pathology. PMID:7790483

Berg, E E

1995-01-01

54

The Use of EZ Derm(R) in Partial-Thickness Burns: An Institutional Review of 157 Patients  

PubMed Central

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. PMID:23573334

Troy, Jared; Karlnoski, Rachel; Downes, Katheryne; Brown, Kimberly S.; Cruse, C. Wayne; Smith, David J.; Payne, Wyatt G.

2013-01-01

55

Acellular flexor tendon allografts: a new horizon for tendon reconstruction.  

PubMed

Flexor tendon injuries continue to pose a significant challenge to the hand surgeon. In particular, chronic tendon ruptures with adhesions of the tendons and sheath, damage or loss of the intrasynovial flexor tendons in zone II, and combined soft tissue and bone injuries present especially difficult problems for restoring satisfactory digital function. This challenge in flexor tendon reconstruction has motivated hand surgeons to explore and develop novel solutions for nearly a century. Recent advances and techniques in processing and decellularizing allograft human flexor tendon constructs may prove to be a new horizon for tendon reconstruction. PMID:23707595

Drake, David B; Tilt, Alexandra C; DeGeorge, Brent R

2013-12-01

56

Allograft tendon for second-stage tendon reconstruction.  

PubMed

Tendons are made of compact dense collagen fibers with only sparse cellularity and naturally low immunogenicity. Allogenic tendons may be preserved through deep freezing methods and retain excellent mechanical properties after revitalization. Allogenic tendons were used in 22 patients (30 tendons) for second-stage tendon reconstruction in the hand. Preliminary results indicate no observable adverse tissue reactions, and functional recovery after tendon grafting does not seem different from reconstruction using tendon autografts. This type of allogenic graft does not seem to produce serious concern as a foreign tissue in the body, at least in the short term. PMID:23101600

Xie, Ren Guo; Tang, Jin Bo

2012-11-01

57

Tendon Gradient Mineralization for Tendon to Bone Interface Integration  

PubMed Central

Tendon-to-bone integration is a great challenge for tendon or ligament reconstruction regardless of use of autograft or allograft tendons. We mineralized the tendon, thus transforming the tendon-to-bone into a “bone-to-bone” interface for healing. Sixty dog flexor digitorum profundus (FDP) tendons were divided randomly into 5 groups: 1) normal FDP tendon, 2) CaP (Non-extraction and mineralization without fetuin), 3) CaPEXT (Extraction by Na2HPO4 and mineralization without fetuin), 4) CaPFetuin (Non-extraction and mineralization with fetuin), and 5) CaPEXTFetuin (Extraction and mineralization with fetuin). The calcium and phosphate content significantly increased in tendons treated with combination of extraction and fetuin compared to the other treatments. Histology also revealed a dense mineral deposition throughout the tendon outer layers and penetrated into the tendon to a depth of 200 ?m in a graded manner. Compressive moduli were significantly lower in the four mineralized groups compared with normal control group. No significant differences in maximum failure strength or stiffness were found in the suture pull-out test among all groups. Mineralization of tendon alters the interface from tendon to bone into mineralized tendon to bone, which may facilitate tendon-to-bone junction healing following tendon or ligament reconstruction. PMID:23939935

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

2014-01-01

58

Imaging of Tendons  

PubMed Central

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. PMID:23015886

Chang, Anthony; Miller, Theodore T.

2009-01-01

59

Bilateral Achilles tendon enlargement.  

PubMed

Cerebrotendinous xanthomatosis is a rare, autosomal-recessive, lipid-storage disease with accumulation of cholestanol in most tissues, particularly within the Achilles tendons. It has been characterized both clinically and biochemically, and recently from the molecular biological aspect as well. Juvenile cataract, childhood diarrhea, mental retardation, cerebellar ataxia, and tendon xanthomas are the most prominent features of this disease. Bilateral symmetrical firm masses of Achilles tendons may be the first symptom the patient recognizes because it can jeopardize his or her ability to walk. However, the treatment strategies for tendon tumors vary. In a recent case, we diagnosed the disease properly, according to the clinical manifestations and the radiological and laboratory examinations. The genetic mutation was characterized by analyzing sterol 27-hydroxylase from the patient's family (located on nucleotide 599) and led to a nonsense mutation. It is a unique type of mutation that has never been reported to our knowledge. Tendon lesions are characterized by the loss of muscle fibers and accumulation of lipid products. To help the patient regain the strength of the Achilles tendon and walking abilities, a large area of tendon tumor was excised, followed by reconstruction with a tibialis posterior allograft, which is the second strongest tendon in the foot and ankle. Although the use of this type of graft is uncommon, the final result was satisfactory. At the 10-month follow-up examination, the patient could walk easily without pain. This case report suggests that the surgical procedure will provide an alternative for the repair of large-area degenerative Achilles tendons. PMID:22146219

Huang, Lu; Miao, Xu-dong; Yang, Di-sheng; Tao, Hui-min

2011-12-01

60

The use of type 1 collagen scaffold containing stromal cell-derived factor-1 to create a matrix environment conducive to partial-thickness cartilage defects repair.  

PubMed

Despite the presence of cartilage-derived mesenchymal stem cells (C-MSCs) and synovial membrane-derived mesenchymal stem cells (SM-MSCs) populations, partial-thickness cartilage defects, in contrast to the full-thickness defects, are devoid of spontaneous repair capacity. This study aims to create an in situ matrix environment conducive to C-MSCs and SM-MSCs to promote cartilage self-repair. Spontaneous repair with MSCs migration into the defect area was observed in full-thickness defects, but not in partial-thickness defects in rabbit model. Ex vivo and in vitro studies showed that subchondral bone or type 1 collagen (col1) scaffold was more permissive for MSCs adhesion than cartilage or type 2 collagen (col2) scaffold and induced robust stromal cell-derived factors-1 (SDF-1) dependent migration of MSCs. Furthermore, creating a matrix environment with col1 scaffold containing SDF-1 enhanced in situ self-repair of partial-thickness defects in rabbit 6 weeks post-injury. Hence, the inferior self-repair capacity in partial-thickness defects is partially owing to the non-permissive matrix environment. Creating an in situ matrix environment conducive to C-MSCs and SM-MSCs migration and adhesion with col1 scaffold containing SDF-1 can be exploited to improve self-repair capacity of cartilage. PMID:23107295

Zhang, Wei; Chen, Jialin; Tao, Jiadong; Jiang, Yangzi; Hu, Changchang; Huang, Lu; Ji, Junfeng; Ouyang, Hong Wei

2013-01-01

61

Posterior Tibial Tendon Dysfunction  

MedlinePLUS

... patients will notice some limitation in activity a er surgery. Anatomy The posterior tibial tendon is one ... the pain to last another 6 months a er treatment starts. Rest Decreasing or even stopping activities ...

62

The tendons: Interventional sonography  

PubMed Central

While blind or fluoroscopically guided infiltration works well for intra-articular injections, injections into the tendon sheath are much more difficult. Ultrasound guidance with high-frequency transducers now allows visualization and infiltration of tendon sheaths. The interventional phase should be preceded by a diagnostic scan. Patients should be questioned to identify possible contraindications to the procedure and informed of the potential risks. Strict asepsis must be maintained for both patient and operator. This review includes separate discussions of the tendons in different areas of the body that are most commonly treated with ultrasound-guided injections, with descriptions of the lesions that are treated and the approach used for each. Interventional sonography is currently the only technique that allows visualization of the tendon being infiltrated. It requires training and experience as well as good knowledge of the indications and equipment used for the procedures, and the anatomy of the areas being treated. PMID:23396899

Campagna, R.; Guerini, H.

2012-01-01

63

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

PubMed

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

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

2013-06-30

64

Neuronal regulation of tendon homoeostasis  

PubMed Central

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

Ackermann, Paul W

2013-01-01

65

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

PubMed Central

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

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

2013-01-01

66

A three-dimensional model of the shoulder girdle. Forces developed in deltoid and supraspinatus muscles during abduction  

Microsoft Academic Search

The aim of this study was to design a three-dimensional model of the human shoulder girdle. Fourteen muscles were modelled geometrically using robotics software (Solid Dynamics System). A static study in reverse dynamics allowed the forces developed in seven muscles to be studied, particularly in the deltoid and supraspinatus during abduction of the arm with the forearm bent at 90°,

M. Scepi; J.-P. Faure; N. Ridoux; P. Kamina; J.-P. Richer

2004-01-01

67

Effect of chondroitinase ABC on adhesion and behavior of synovial membrane-derived mesenchymal stem cells in rabbit partial-thickness chondral defects.  

PubMed

Transplanted cells may have difficulty attaching to the surface of partial-thickness chondral lesions because of the anti-adhesive properties of the proteoglycan rich matrix. Therefore, the current study attempts to evaluate the effect of chondroitinase ABC (chABC) on the adhesion and behavior of transplanted synovial membrane-derived mesenchymal stem cells (SDSCs) in rabbit partial-thickness chondral defects. In ex vivo adhesion experiments, chABC treatment (0.1?U/ml) was increased in SDSC attachment to the cartilage explants, and significantly diminished by pretreatment with neutralizing antibody against fibronectin. In the in vivo experiments, 1 day and 4 weeks after the chABC treatment (0.1 and 1?U/ml), the immunoreactivity (IR) against CS-56 (intact chondroitin sulfate antibody) was markedly decreased; however, the IR of 2B6 (stub of the chondroitin 4-sulfate chain), 3B3 (stub of the chondroitin 6-sulfate chain), and fibronectin was increased. At 12 weeks, this IR returned to normal except in the high-dose chABC-treated group (1?U/ml). Furthermore, the attachment of SDSCs to the chondral defects after chABC treatment was increased at 7 days compared with that in the chondral defects pretreated with saline. However, the tissue repaired by SDSCs was negatively stained for type II collagen at 12 weeks. In conclusion, these results showed that the exposure to fibronectin by chABC treatment enhances the attachment of SDSCs to partial-thickness chondral defects. However, the tissue regenerated by SDSCs showed lack of hyaline cartilage regeneration. Thus, to understand the fate of transplanted MSCs in cartilage defect is very important for successful cell therapies. PMID:23629810

Lee, Jae-Chul; Min, Hyun Jin; Lee, Sahnghoon; Seong, Sang Cheol; Lee, Myung Chul

2013-08-01

68

Peroneal tendons subluxation.  

PubMed

Subluxation of the peroneal tendons is uncommon. It occurs especially in skiing, soccer, basketball, rugby, ice skating, judo, sprint, water-skiing, mountaineering, and gymnastics. We present an overview of the injury, with the classification commonly used. Many surgical techniques have been described to manage recurrent subluxation of the peroneal tendons, but only Level IV/Grade C evidence has been produced. Thus, randomized controlled trials are necessary to determinate the best surgical management method. It appears that high-demand individuals should be primarily managed surgically, and retinaculoplasty seems to be, when indicated, the best surgical option: it affords less complications and a high rate of return to sports without reducing their activity levels. PMID:19440138

Oliva, Francesco; Del Frate, Dario; Ferran, Nicholas Antonio; Maffulli, Nicola

2009-06-01

69

Scaffolds in Tendon Tissue Engineering  

PubMed Central

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

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

2012-01-01

70

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

PubMed Central

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

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

2007-01-01

71

Effects of a topical aqueous oxygen emulsion on collagen deposition and angiogenesis in a porcine deep partial-thickness wound model.  

PubMed

A porcine deep partial-thickness wound model was used to evaluate the effects of a newly developed topical aqueous oxygen emulsion (TOE) on wound repair. The wounds were treated with TOE, which contains super-saturated oxygen or vehicle control. Semiquantitative immunofluorescent staining was performed to examine protein production for type I and type III collagen and vascular endothelial growth factor (VEGF). Immunofluorescent staining revealed higher protein levels of type I and type III collagen and VEGF in the TOE treatment group. Histological analysis also revealed improved angiogenesis and granulation tissue formation with topical TOE treatment and was consistent with the protein expression. In addition, the histology examination demonstrated faster epithelialization in wounds treated with TOE. The study suggests that sustained high levels of oxygen released by TOE may promote the process of wound repair through increasing collagen deposition and angiogenesis as well as stimulating epithelialization. PMID:24079742

Li, Jie; Ollague Sierra, Jose; Zhu, Linjian; Tang, Ling; Rahill, Kirah; El-Sabawi, Bassim; Liu-Mares, Wen; Mertz, Patricia M; Davis, Stephen C

2013-10-01

72

Pain control in a randomized, controlled, clinical trial comparing moist exposed burn ointment and conventional methods in patients with partial-thickness burns.  

PubMed

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

2003-01-01

73

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

PubMed

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

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

2014-01-01

74

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

PubMed Central

Purpose/Background: Several examination tests are currently used for diagnosing a supraspinatus lesion. The empty can (EC) test is currently considered the gold standard for testing, but full can (FC) testing is also utilized. Both of these tests do not fully eliminate the deltoid synergistic when resistance is applied. A new diagonal horizontal adduction (DHA) technique has been developed for evaluation of the supraspinatus that has not yet been compared with the existing techniques (EC/FC). Cross?sectional analysis (CSA) change during contraction as an ultrasonographic means of visualizing and measuring contraction of the supraspinatus has been reported previously. Objective: The purpose of this study was to use diagnostic musculoskeletal ultrasound (MSK) to compare CSA of the supraspinatus during the FC, EC, and the DHA tests. Methods: The supraspinatus muscle of 37 healthy, uninjured volunteers (21 males and 16 females, mean age of 26.9) were visualized and CSA was captured during 4 randomly assigned test positions (including control) using MSK. Results: A one?way Analysis of Variance with repeated measures of the mean CSA obtained in the testing positions was performed followed by least significant difference (LSD) for post?hoc analysis. Significant differences (p < 0.05) were found between the mean CSA of the controls and the CSA of each of the three testing procedures analyzed using the MSK. There were no significant differences (p < 0.05) in CSA between any of the three testing procedures. Conclusions: In this study, MSK visualized and objectified activity of the supraspinatus muscle as evidenced through increased mean CSA when resisted. All the testing positions (FC, EC, and DHA) demonstrated significantly increased mean CSA of the muscle when isometrically contracted when compared to the resting control. The DHA procedure also elicited significant increase in CSA of the supraspinatus. However, no significant difference was found between the CSA of the DHA when compared to the FC and EC tests. Level of Evidence: Level 2 PMID:23772340

White, Douglas M.; Smith, Wayne

2013-01-01

75

Effect of chitosan-gluconic acid conjugate/poly(vinyl alcohol) cryogels as wound dressing on partial-thickness wounds in diabetic rats.  

PubMed

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

2013-10-01

76

The Changes of Electromyography in the Upper Trapezius and Supraspinatus of Women College Students According to the Method of Bag-carrying and Weight  

PubMed Central

[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. PMID:24259929

Cho, Sung-Hyoun; Lee, Jung-Ho; Kim, Cheol-Yong

2013-01-01

77

The Changes of Electromyography in the Upper Trapezius and Supraspinatus of Women College Students According to the Method of Bag-carrying and Weight.  

PubMed

[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. PMID:24259929

Cho, Sung-Hyoun; Lee, Jung-Ho; Kim, Cheol-Yong

2013-09-01

78

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

PubMed

Quadriceps tendon with a patellar bone block may be a viable alternative to Achilles tendon for anterior cruciate ligament reconstruction (ACL-R) if it is, at a minimum, a biomechanically equivalent graft. The objective of this study was to directly compare the biomechanical properties of quadriceps tendon and Achilles tendon allografts. Quadriceps and Achilles tendon pairs from nine research-consented donors were tested. All specimens were processed to reduce bioburden and terminally sterilized by gamma irradiation. Specimens were subjected to a three phase uniaxial tension test performed in a custom environmental chamber to maintain the specimens at a physiologic temperature (37 ± 2 °C) and misted with a 0.9 % NaCl solution. There were no statistical differences in seven of eight structural and mechanical between the two tendon types. Quadriceps tendons exhibited a significantly higher displacement at maximum load and significantly lower stiffness than Achilles tendons. The results of this study indicated a biomechanical equivalence of aseptically processed, terminally sterilized quadriceps tendon grafts with bone block to Achilles tendon grafts with bone block. The significantly higher displacement at maximum load, and lower stiffness observed for quadriceps tendons may be related to the failure mode. Achilles tendons had a higher bone avulsion rate than quadriceps tendons (86 % compared to 12 %, respectively). This was likely due to observed differences in bone block density between the two tendon types. This research supports the use of quadriceps tendon allografts in lieu of Achilles tendon allografts for ACL-R. PMID:24414293

Mabe, Isaac; Hunter, Shawn

2014-12-01

79

Position Control of Tendon-Driven Fingers.  

National Technical Information Service (NTIS)

Conventionally, tendon-driven manipulators implement some force control scheme based on tension feedback. This feedback allows the system to ensure that the tendons are maintained taut with proper levels of tensioning at all times. Occasionally, whether i...

B. Hargrave, F. Pementer, M. E. Abdallah, R. Platt

2011-01-01

80

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

PubMed

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

2014-01-01

81

Flexor tendon injuries in the child.  

PubMed

This review aims to highlight the differences in the management of flexor tendon injuries between children and adults. These include differences in epidemiology, anatomy, classification, diagnosis, incisions and skin closure, the size of the flexor tendons, technical aspects of zones I and II repairs, core suture purchase length, rehabilitation, results, and complications of primary flexor tendon repair. Finally, one- versus two-stage flexor tendon reconstruction in children is reviewed. PMID:23855037

Al-Qattan, M M

2014-01-01

82

Achilles tendon reflex measuring system  

NASA Astrophysics Data System (ADS)

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

Szebeszczyk, Janina; Straszecka, Joanna

1995-06-01

83

Common Disorders of the Achilles Tendon  

MedlinePLUS

... tendon is then altered, resulting in continued pain. Athletes are at high risk for developing disorders of the Achilles tendon. Achilles tendonitis and tendonosis are also common in individuals whose work puts stress on their ankles and feet, such as laborers, ...

84

The cell biology of suturing tendons  

Microsoft Academic Search

Trauma by suturing tendon form areas devoid of cells termed “acellular zones” in the matrix. This study aimed to characterise the cellular insult of suturing and acellular zone formation in mouse tendon. Acellular zone formation was evaluated using single grasping sutures placed using flexor tendons with time lapse cell viability imaging for a period of 12h. Both tension and injury

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

2010-01-01

85

Can PRP effectively treat injured tendons?  

PubMed Central

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. PMID:24932445

Wang, James H-C.

2014-01-01

86

Efficacy of various analgesics on shoulder function and rotator cuff tendon-to-bone healing in a rat (Rattus norvegicus) model.  

PubMed

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

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

2014-03-01

87

Hyperuricemic PRP in Tendon Cells  

PubMed Central

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

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

2014-01-01

88

Human tendon behaviour and adaptation, in vivo  

PubMed Central

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

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

2008-01-01

89

Active Achilles tendon kinesitherapy accelerates Achilles tendon repair by promoting neurite regeneration?  

PubMed Central

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

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

2012-01-01

90

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

PubMed

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

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

2012-12-15

91

Flexor tendon injuries in athletes.  

PubMed

Flexor tendon injuries are not common in most sporting venues; however, recognition of the pertinent anatomy, clinical findings, and the utility of diagnostic imaging will assist the clinician in a thorough evaluation of the athlete's hand. Open injuries demand immediate wound care and evaluation as to the integrity of the flexor apparatus; however, closed injuries often present with the challenges of timing: delayed injury presentation and pressures of intervention and return to play. The purpose of this article is to provide a review of the pertinent anatomy of the flexor apparatus of the hand, to identify key aspects of the patient history, clinical evaluation, and diagnostic testing relevant to flexor function, and to discuss treatment options in the setting of injuries to the flexor tendons and flexor pulley system of the hand. PMID:24651291

Neumann, Julie A; Leversedge, Fraser J

2014-03-01

92

Achilles tendon rupture in badminton.  

PubMed Central

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. PMID:2605439

Kaalund, S; Lass, P; Høgsaa, B; Nøhr, M

1989-01-01

93

Les plaies du tendon patellaire  

PubMed Central

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

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

2014-01-01

94

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

PubMed

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

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

2014-05-01

95

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

PubMed Central

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

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

2011-01-01

96

Triceps tendon rupture in weight lifters.  

PubMed

Triceps tendon avulsion injuries are rare. We report four weight lifters with triceps tendon raptures, two of whom had received local steroid injections for pain in the triceps. All four patients had taken oral anabolic steroids before injury. All patients had closed avulsion of the triceps tendon from its insertion into the olecranon. Three patients were injured while bench pressing heavy weights, and one patient was injured while swinging a baseball bat. Satisfactory results were achieved after surgical reinsertion of the tendon. PMID:9593095

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

1998-01-01

97

Recent developments in flexor tendon repair techniques and factors influencing strength of the tendon repair.  

PubMed

Over the last decade, both basic researchers and surgeons have sought to identify the most appropriate techniques to be applied in flexor tendon repairs. Recent developments in experimental tendon repairs and clinical outcomes of newer repair techniques have been reviewed in an attempt to comprehensively summarize the most critical mechanical factors affecting the performance of tendon repairs and the surgical factors influencing clinical outcomes. Among them, attention to annular pulleys, the purchase and tension of the core suture, and the direction and curvature of the path of tendon motion have been found to be determining factors in the results of tendon repair. PMID:23792441

Wu, Y F; Tang, J B

2014-01-01

98

Effect of triggering and entrapment on tendon gliding properties following digital flexor tendon laceration: in vitro study on turkey tendon.  

PubMed

The optimal management of partial flexor tendon laceration is controversial and remains a clinical challenge. Abnormal tendon gliding (triggering and entrapment) was assessed at the A2 pulley in 40 turkey tendons in three groups: intact, partially divided (palmar or lateral), and trimmed. Testing was of gliding resistance and friction coefficient at 30° and 70° of flexion, loaded with 2 and 4 N. We observed for triggering and entrapment. The changes in gliding properties were compared and analysed using Wilcoxon matched pair testing. A significant difference was found in the change in gliding properties of intact to lacerated and lacerated to trimmed tendons and between tendons that glided normally compared with those exhibiting triggering or entrapment. This suggests that palmar and lateral lacerations which, through clinical examination and visualization, are found to glide normally should be treated with early mobilization. However, partial lacerations that exhibit triggering or entrapment should be trimmed. PMID:23735810

Kennedy, J A; Dias, J J

2014-09-01

99

Extensor tendon injury due to repetitive wrist dorsiflexion: morphological study of extensor retinaculum and extensor tendon.  

PubMed

Most etiological studies of extensor tendon injury were based on the normal anatomy of extensor tendon and extensor retinaculum of the wrist. Further understanding of the morphological changes of the extensor tendon and extensor retinaculum during wrist dorsiflexion might contribute to improved and more accurate understanding of the etiology. The morphology of the extensor tendon of the mid-finger and the fourth compartment of the wrist extensor retinaculum was studied by sonography, and the anatomy was studied in 15 extremities from 11 young male cadavers. Compared with anatomical images, ultrasonography provides similar morphological observations of the extensor retinaculum of the wrist and extensor tendon. Ultrasonography findings revealed that as the dorsiflexion angle changed, the extensor retinaculum of the wrist formed different shaped trochleas. The trochlea guides the rotation of the extensor tendon at the wrist, but it does not form a sharp corner with the extensor tendon; thus, the extensor tendon is not compressed. As the dorsiflexion angle increased from 0° to 60°, the length of the trochlea gradually decreases. The shortening of the trochlea length will lead to a smaller frictional contact area between the extensor tendon and the extensor retinaculum. Consequently, the friction is centralized. During wrist dorsiflexion, the extensor retinaculum provides a trochlea for the extensor tendon. Extensor tendon injury of repetitive wrist dorsiflexion might be caused by centralized friction at the small contact area. PMID:24902538

Zhou, Chang-Long; Wang, Xin-Tao; Chi, Zhi-Yong; Yan, Jing-Long

2014-11-01

100

Calcific tendonitis of the tibialis posterior tendon at the navicular attachment  

PubMed Central

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

Harries, Luke; Kempson, Susan; Watura, Roland

2011-01-01

101

Estimating upper extremity tendon slack lengths  

Microsoft Academic Search

Tendon slack lengths are used in a dynamic muscle and limb model to animate the upper extremity based on user supplied activation levels. This paper provides tendon slack length estimates for actuators crossing the elbow and inserting on the radius or ulna. These values were not previously available as a complete see for the upper extremity. Muscle parameters used in

Brian R. von Konsky

1995-01-01

102

Mechanical properties of model synthetic tendons.  

PubMed

Model synthetic tendons consisting of 20 vol % of texturized poly(ethylene terephthalate) fibers and of the water-swollen poly(2-hydroxyethyl methacrylate) matrix have the tensile modulus E = 1.5 +/- 0.1 GPa, strength and strain-at-break sigma b = 85 +/- 10 MPa and epsilon b = 0.08 +/- 0.02. The force required for breaking tendons with the diameters 2, 3, 4 mm is, respectively, 300, 500, and 960 N. By these properties model synthetic tendons closely imitate the properties of natural tendons. Long-term (100 min) and repeated short-term (30 times 1 min) creep shows that on loading model tendons lose some 10% of their stiffness, but that the whole deformation is reversible. The shape of the compliance vs. time dependence of synthetic tendons closely resembles the dependence determined for the parent fiber. The stiffness and strength of a tendon are given by those of the fiber bundle used; by varying fiber volume fraction, it is possible to adjust the required mechanical properties of tendons. PMID:7348710

Kolarík, J; Migliaresi, C; Stol, M; Nicolais, L

1981-03-01

103

Unusual rupture of a flexor profundus tendon.  

PubMed

An unusual rupture of a flexor profundus tendon, previously unreported in the literature, is presented. There was avulsion and proximal displacement of a large bone fragment from the palmar base of the distal phalanx and further retraction of the tendon unattached to the bone fragment. PMID:3958452

Langa, V; Posner, M A

1986-03-01

104

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

PubMed

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

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

2014-10-01

105

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

PubMed Central

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

Gulick, Dawn T.; Yoder, Heather N.

2002-01-01

106

Supraspinatus and infraspinatus weakness in overhead athletes with scapular dyskinesis: strength assessment before and after restoration of scapular musculature balance.  

PubMed

A disturbance in scapulohumeral rhythm may cause negative biomechanic effects on rotator cuff (RC). Alteration in scapular motion and shoulder pain can influence RC strength. Purpose of this study was to assess supraspinatus and infraspinatus strength in 29 overhead athletes with scapular dyskinesis, before and after 3 and 6 months of rehabilitation aimed to restore scapular musculature balance. A passive posterior soft tissues stretching was prescribed to balance shoulder mobility. Scapular dyskinesis patterns were evaluated according to Kibler et al. Clinical assessment was performed with the empty can (EC) test and infraspinatus strength test (IST). Strength values were recorded by a dynamometer; scores for pain were assessed with VAS scale. Changes of shoulder IR were measured. The force values increased at 3 months (P < 0.01) and at 6 months (P < 0.01). Changes of glenohumeral IR and decrease in pain scores were found at both follow-up. Outcomes registered on pain and strength confirm the role of a proper scapular position for an optimal length-tension relationship of the RC muscles. These data should encourage those caring for athletes to consider restoring of scapular musculature balance as essential part of the athletic training. PMID:21069487

Merolla, Giovanni; De Santis, Elisa; Campi, Fabrizio; Paladini, Paolo; Porcellini, Giuseppe

2010-12-01

107

Primary hydatid cyst of the supraspinatus muscle: complete removal of the germinal layer and cytodiagnosis by fine-needle aspiration.  

PubMed

Primary hydatid disease of the skeletal muscle without systemic involvement is rare. The purpose of this report is to document the novel clinical presentation and the interesting facets of fine-needle aspiration in a case of hydatid disease. It was a case of primary hydatid cyst of the left supraspinatus muscle in an Indian woman living in Kuwait, which was clinically diagnosed as a lipoma. Fine-needle aspiration (FNA) yielded 2 ml of clear fluid with white particulate material. The cytocentrifuged smears prepared from the aspirated fluid showed many scolices, occasional laminated cyst wall fragments and numerous hooklets. The laminated cyst wall and scolices were PAS positive. Trichrome staining imparted a demon-head-like appearance to the scolices. The cytodiagnosis of hydatid cyst was corroborated by histopathological examination of an excised whitish membrane and an irregular cystic fragment, which showed parallel laminations without germinal layer, and skeletal muscle with granulomas and a dense eosinophilic infiltration, respectively. Quantitative serological (indirect hemagglutination) test on blood sample collected 9 days after the excision of the cyst showed insignificant antibody titer to Echinococcus sp. and after 6 weeks the antibodies were completely absent. CT scan of the chest and abdomen performed 7 weeks after removal of cyst showed no evidence of visceral hydatid cyst. PMID:23008130

Das, Dilip K; El-Sharawy, Maha; Ayyash, Emad H; Al-Enezi, Nadia A; Iqbal, Jamshed R; Madda, John P

2014-03-01

108

Intrasynovial Tendon Graft for Chronic Flexor Tendon Laceration of the Finger: A Case Report  

PubMed Central

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. PMID:24015158

Sasaki, Jun; Itsubo, Toshiro; Nakamura, Koichi; Hayashi, Masanori; Uchiyama, Shigeharu; Kato, Hiroyuki

2013-01-01

109

Uncommon methods of flexor tendon and tendon-bone repairs and grafting.  

PubMed

The conventional practices used in flexor tendon repair have remained unchanged in many units. Because clinical cases vary considerably, some situations may merit more unusual methods. Here the author describes a few methods that have been used in flexor tendon repair. This article discusses a few methods that are clinically useful in treating some patients but are not commonly described. The newer tendon-bone junction methods exemplified here would likely replace the pull-out suture. Late direct repair and lengthening plasty require the accumulation of clinical experience. Allograft tendon reconstruction has shown successful midterm results, but long-term follow-up is certainly necessary. PMID:23660057

Tang, Jin Bo

2013-05-01

110

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

PubMed

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

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

2014-01-01

111

Skeletal muscle fibrosis and stiffness increase after rotator cuff tendon injury and neuromuscular compromise in a rat model.  

PubMed

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. PMID:24838823

Sato, Eugene J; Killian, Megan L; Choi, Anthony J; Lin, Evie; Esparza, Mary C; Galatz, Leesa M; Thomopoulos, Stavros; Ward, Samuel R

2014-09-01

112

Traumatic flexor tendon injuries in 27 cattle.  

PubMed

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

1996-01-01

113

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

PubMed

Tendons are strong hierarchical structures, but how tensile forces are transmitted between different levels remains incompletely understood. Collagen fibrils are thought to be primary determinants of whole tendon properties, and therefore we hypothesized that the whole human patellar tendon and its distinct collagen fibrils would display similar mechanical properties. Human patellar tendons (n = 5) were mechanically tested in vivo by ultrasonography. Biopsies were obtained from each tendon, and individual collagen fibrils were dissected and tested mechanically by atomic force microscopy. The Young's modulus was 2.0 ± 0.5 GPa, and the toe region reached 3.3 ± 1.9% strain in whole patellar tendons. Based on dry cross-sectional area, the Young's modulus of isolated collagen fibrils was 2.8 ± 0.3 GPa, and the toe region reached 0.86 ± 0.08% strain. The measured fibril modulus was insufficient to account for the modulus of the tendon in vivo when fibril content in the tendon was accounted for. Thus, our original hypothesis was not supported, although the in vitro fibril modulus corresponded well with reported in vitro tendon values. This correspondence together with the fibril modulus not being greater than that of tendon supports that fibrillar rather than interfibrillar properties govern the subfailure tendon response, making the fibrillar level a meaningful target of intervention. The lower modulus found in vitro suggests a possible adverse effect of removing the tissue from its natural environment. In addition to the primary work comparing the two hierarchical levels, we also verified the existence of viscoelastic behavior in isolated human collagen fibrils. PMID:22114175

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

2012-02-01

114

The cell biology of suturing tendons  

PubMed Central

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

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

2010-01-01

115

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

PubMed

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

2011-12-01

116

Bio-engineered synovial membrane to prevent tendon adhesions in rabbit flexor tendon model.  

PubMed

During tendon injuries, the tendon sheath is also damaged. This study aims to test effectiveness of engineered tendon synovial cell biomembrane on prevention of adhesions. Forty New Zealand Rabbits enrolled into four study groups. Engineered synovial sheath was produced by culturing cell suspension on fabricated collagen matrix membrane. Study groups were: tendon repair (group A), tendon repair zone covered with plane matrix (Group B), synovial suspension injection into the zone of repair over matrix (Group C), and biomembrane application (Group D). Biomechanical evaluations of tendon excursion, metacarpophalangeal and proximal interphalangeal joints range of motion, H&E and Alcian Blue with neutral red staining, and adhesion formation graded for histological assessments were studied. Ten non-operated extremities used as control. Tendon excursions and range of motions were significantly higher and close to control group for Group D, p??0.005. Hyaluronic acid synthesis was demonstrated at groups C and D at the zone of injury. Application of synovial cells into the tendon repair zone either by cell suspension or within a biomembrane significantly decreases the adhesion formation. Barrier effect of collagen matrix and restoration of hyaluronic acid synthesis can explain the possible mechanism of action. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 84-90, 2015. PMID:24616375

Baymurat, Alim Can; Ozturk, Akif Muhtar; Yetkin, Haluk; Ergun, Mehmet Ali; Helvac?oglu, Fatma; Ozk?z?lc?k, Asya; Tuzlako?lu, Kadriye; Sener, E Ertugrul; Erdogan, Deniz

2015-01-01

117

The effect of decellularized matrices on human tendon stem/progenitor cell differentiation and tendon repair.  

PubMed

It is reported that decellularized collagen matrices derived from dermal skin and bone have been clinically used for tendon repair. However, the varying biological and physical properties of matrices originating from different tissues may influence the differentiation of tendon stem cells, which has not been systematically evaluated. In this study, the effects of collagenous matrices derived from different tissues (tendon, bone and dermis) on the cell differentiation of human tendon stem/progenitor cells (hTSPCs) were investigated, in the context of tendon repair. It was found that all three matrices supported the adhesion and proliferation of hTSPCs despite differences in topography. Interestingly, tendon-derived decellularized matrix promoted the tendinous phenotype in hTSPCs and inhibited their osteogenesis, even under osteogenic induction conditions, through modulation of the teno- and osteolineage-specific transcription factors Scleraxis and Runx2. Bone-derived decellularized matrix robustly induced osteogenic differentiation of hTSPCs, whereas dermal skin-derived collagen matrix had no apparent effect on hTSPC differentiation. Based on the specific biological function of the tendon-derived decellularized matrix, a tissue-engineered tendon comprising TSPCs and tendon-derived matrix was successfully fabricated for Achilles tendon reconstruction. Implantation of this cell-scaffold construct led to a more mature structure (histology score: 4.08 ± 0.61 vs. 8.51 ± 1.66), larger collagen fibrils (52.2 ± 1.6 nm vs. 47.5 ± 2.8 nm) and stronger mechanical properties (stiffness: 21.68 ± 7.1 Nm m(-1) vs.13.2 ± 5.9 Nm m(-1)) of repaired tendons compared to the control group. The results suggest that stem cells promote the rate of repair of Achilles tendon in the presence of a tendinous matrix. This study thus highlights the potential of decellularized matrix for future tissue engineering applications, as well as developing a practical strategy for functional tendon regeneration by utilizing TSPCs combined with tendon-derived decellularized matrix. PMID:23896565

Yin, Zi; Chen, Xiao; Zhu, Ting; Hu, Jia-jie; Song, Hai-xin; Shen, Wei-liang; Jiang, Liu-yun; Heng, Boon Chin; Ji, Jun-feng; Ouyang, Hong-Wei

2013-12-01

118

Specialization of tendon mechanical properties results from interfascicular differences.  

PubMed

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

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

2012-11-01

119

The effect of tendon surface treatment on cell attachment for potential enhancement of tendon graft healing: an ex vivo model.  

PubMed

For both tendon allografts and autografts, the surface, initially optimized for gliding, may not be ideal to facilitate tissue integration for graft healing to host tendon or bone. As a prelude to studying tendon-bone integration, we investigated the effect of surface treatments with trypsin or mechanical abrasion on cell attachment to the tendon surface in a canine ex vivo intrasynovial tendon tissue culture model. Intrasynovial tendon allograft surfaces were seeded with cells after the following treatments: (1) no treatment, (2) mechanical abrasion, (3) trypsin, and (4) abrasion and trypsin. The area covered by cells was determined using confocal laser microscopy at one and two weeks. Results were compared to untreated extrasynovial tendon. Additional tendons were characterized with scanning electron microscopy. Tendons with trypsin treatment had significantly more surface coverage with cells than the other groups, after both one and two weeks of culture. In terms of the cellular shape and size, cells on tendons with trypsin treatment spread more and were more polygonal in shape, whereas tendons with mechanical abrasion with/without trypsin treatment contained smaller, more spindle-like cells. Surface roughening can affect cell behavior with topographical stimulation. Trypsin surface digestion exposes a mesh-like structure on the tendon surface, which could enhance cell adherence and, possibly, tendon/bone healing. PMID:22349134

Hashimoto, Takahiro; Sun, Yu-Long; An, Kai-Nan; Amadio, Peter C; Zhao, Chunfeng

2012-12-01

120

Protect Your Tendons: Preventing the Pain of Tendinitis  

MedlinePLUS

... External link, please review our exit disclaimer . Subscribe Protect Your Tendons Preventing the Pain of Tendinitis You’ ... long into old age. search Features Managing Asthma Protect Your Tendons Wise Choices Links Preventing Tendinitis Exercise ...

121

Structure-function relationships in tendons: a review  

PubMed Central

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

Benjamin, M; Kaiser, E; Milz, S

2008-01-01

122

[The Achilles tendon in sports].  

PubMed

Achillodynia is a generic term for various types of ailments in the region of the Achilles tendon. For adequate therapy a specific diagnosis is absolutely necessary. Besides an accurate anamnesis and the right choice of terrain and shoes, as well as a clinical examination where one has to specifically keep an eye on muscular imbalance between the gastrocnemius and the soleus muscle and disorders of the ligamentous control of the calcaneus caused by fibular ligament instabilities, a procedure such as radiology, ultrasound, and MR imaging is inevitable. From the differential diagnosis point of view a distinction between peritendinitis, mechanically triggered bursitis (calcaneal and subachilles), bony alterations of the calcaneus (calcaneus spur, Haglund exostosis persistent nucleus of the apophysis, fatigue fracture, etc) and a partial or total rupture (a one-time occurrence or multiple occurrences) has to be made. Occasionally, entrapment of the ramus calcaneus of the sural nerve causes calcaneal pain. If clinically not confirmed, lumbar pain ought to be taken into consideration (discopathy, Bechterew disease, etc). Metabolic disorders (especially uric acid) and underlying rheumatic diseases must be excluded. The therapy of achillodynia includes local and peroral antiphlogistic medication as a concomitant measure. More important is the causal influence of etiological factors, i.e., the correction of muscular imbalance, ensuring control of the calcaneus through bandages and adjustment of sport shoes, changes in training buildup and exercise intensity, just to mention a few. If necessary, surgically splitting the peritendineum, sanitation of a partial rupture, bursectomy and removal of mechanically obstructive exostosis must be done. PMID:7617382

Segesser, B; Goesele, A; Renggli, P

1995-06-01

123

Snapping knee: An unusual biceps femoris tendon injury  

Microsoft Academic Search

We report a case of acute post-traumatic snapping of the biceps femoris tendon following a soccer injury. Surgical stabilisation, achieved by re-routing the tendon insertion through a tunnel in the fibular head, resolved the symptoms after conservative management failed. We believe this is the first report of a ‘snapping knee’ resulting from direct injury to the biceps femoris tendon insertion.

Rajeev Bansal; Chris Taylor; Ashvin L. Pimpalnerkar

2005-01-01

124

An Overview of the Management of Flexor Tendon Injuries  

PubMed Central

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

2012-01-01

125

Platelet-rich plasma (prp) and tendon healing: animal model  

Microsoft Academic Search

IntroductionThe tendon is a tissue which does not heal easily. Recently, several studies have demonstrated the positive effects of platelets on the healing process of tendons. A local injection of platelet-rich plasma (PRP), which releases in situ many growth factors, has the potentiality to enhance the tendon healing process. The aim of our experiment was to ascertain by an original

J F Kaux; P Drion; J Renouf; F Pascon; V Libertiaux; A Colige; C Le Goff; C Lambert; B Nusgens; A Gothot; S Cescotto; J O Defraigne; M Rickert; J M Crielaard

2011-01-01

126

The integrated function of muscles and tendons during locomotion  

Microsoft Academic Search

The mechanical roles of tendon and muscle contractile elements during locomotion are often considered independently, but functionally they are tightly integrated. Tendons can enhance muscle performance for a wide range of locomotor activities because muscle–tendon units shorten and lengthen at velocities that would be mechanically unfavorable for muscle fibers functioning alone. During activities that require little net mechanical power output,

Thomas J. Roberts

2002-01-01

127

Microcirculatory effects of topical glyceryl trinitrate on the Achilles tendon microcirculation in patients with previous Achilles tendon rupture.  

PubMed

Topical glyceryl trinitrate treatment has demonstrated short- to mid-term efficacy in chronic noninsertional Achilles tendinopathy. However, the underlying mechanisms are far from being understood. We hypothetized that Achilles tendon capillary blood flow changes immediately after topical glyceryl trinitrate treatment. Fifteen patients (55 + or - 15 years, VAS 5.8 + or - 2.3) with current mid-portion Achilles tendon pain 36 months after open surgical Achilles tendon repair for tendon rupture were included. On the Achilles mid-portion, 1.2 mg topical glyceryl trinitrate was sprayed. Microcirculatory monitoring included capillary blood flow, tendon oxygen saturation and postcapillary venous filling pressures at the insertion and 2, 4 and 6 cm above the insertion using a combined laser Doppler and spectrophotometry system. Baseline capillary blood-flows of the painful versus the uninjured tendon were increased [108 + or - 46 vs. 81 + or - 20 (2 cm above the insertion), 104 + or - 40 vs. 76 + or - 20 (4 cm above the insertion), 111 + or - 53 vs. 90 + or - 21 (6 cm above the insertion, P < 0.05)]. However, topical glyceryl trinitrate did not change capillary blood-flow at 2 and 8-mm tissue depths at the painful Achilles tendon or the healthy tendon. Tendon oxygenation was not changed at the painful or the healthy Achilles tendon. Postcapillary venous filling pressure was reduced at 8 mm at the mid-portion in the painful Achilles tendon only (113 + or - 37 vs. 95 + or - 31, P = 0.030). Acute topical glyceryl trinitrate facilitates capillary venous outflow in painful Achilles tendons. However, capillary blood-flow and tendon oxygenation remain unchanged following acute topical glyceryl trinitrate application. Elevated capillary blood-flow at the entire mid-portion is encountered at baseline in previously ruptured painful Achilles tendons even 3 years after surgical repair of the Achilles tendon indicating an altered microcirculatory flow pattern. PMID:19882141

Osadnik, Rafal; Redeker, Joern; Kraemer, Robert; Vogt, Peter M; Knobloch, Karsten

2010-07-01

128

A preliminary study of patellar tendon torques during jumping.  

PubMed

The etiology of patellar tendinopathy (jumper's knee) has been attributed to a significant increase in patellar tendon torques associated with jumping. While some investigators have suggested that patellar tendon torques are greater during takeoff, little is known about the relative magnitudes of patellar tendon torques during takeoff and landing. We hypothesized that peak patellar tendon torques are greater in jump takeoff than in landing, and that there is a linear correlation between jump height and peak patellar tendon torque. Seven asymptomatic, recreational male athletes each performed a series of 21 jumps ranging from low to maximal height. A calibrated fiber-optic sensor, implanted transversely within the patellar tendon was used to measure the knee torque during takeoff and landing. There was no significant difference in the peak patellar tendon torque experienced during takeoff and landing within individuals. There was a moderate correlation (r = .64) between maximum takeoff patellar tendon torques and jump height. There was a weak correlation (r = .52) between maximum landing patellar tendon torques and jump height. There was a moderate correlation (r = .67) between maximum 60 degrees/s isokinetic extension torque and maximum jump height. The lack of a strong correlation between jump height and patellar tendon forces during take-off or landing suggests that these forces may be technique dependent. Therefore, modifying takeoff and/or landing techniques could reduce patellar tendon force and potentially lessen the incidence of patellar tendinopathy. PMID:20095457

Elvin, Niell; Elvin, Alex; Scheffer, Cornie; Arnoczky, Steven; Dillon, Edwin; Erasmus, P J

2009-11-01

129

Achilles Tendon Repair, A Modified Technique  

PubMed Central

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

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

2013-01-01

130

Tendon fatigue in response to mechanical loading.  

PubMed

Tendinopathies are commonly attributable to accumulation of sub-rupture fatigue damage from repetitive use. Data is limited to late stage disease from patients undergoing surgery, motivating development of animal models, such as ones utilizing treadmill running or repetitive reaching, to investigate the progression of tendinopathies. We developed an in vivo model using the rat patellar tendon that allows control of the loading directly applied to the tendon. This manuscript discusses the response of tendons to fatigue loading and applications of our model. Briefly, the fatigue life of the tendon was used to define low, moderate and high levels of fatigue loading. Morphological assessment showed a progression from mild kinks to fiber disruption, for low to high level fatigue loading. Collagen expression, 1 and 3 days post loading, showed more modest changes for low and moderate than high level fatigue loading. Protein and mRNA expression of Ineterleukin-1? and MMP-13 were upregulated for moderate but not low level fatigue loading. Moderate level (7200 cycles) and 100 cycles of fatigue loading resulted in a catabolic and anabolic molecular profile respectively, at both 1 and 7 days post loading. Results suggest unique mechanisms for different levels of fatigue loading that are distinct from laceration. PMID:21625047

Andarawis-Puri, N; Flatow, E L

2011-06-01

131

Mechanical compromise of partially lacerated flexor tendons.  

PubMed

Tendons function to transmit loads from muscle to move and stabilize joints and absorb impacts. Functionality of lacerated tendons is diminished, however clinical practice often considers surgical repair only after 50% or more of the tendon is lacerated, the "50% rule." Few studies provide mechanical insight into the 50% rule. In this study cyclic and static stress relaxation tests were performed on porcine flexor tendons before and after a 0.5, 1.0, 2.0, or 2.75?mm deep transverse, midsubstance laceration. Elastic and viscoelastic properties, such as maximum stress, change in stress throughout each test, and stiffness, were measured and compared pre- and post-laceration. Nominal stress and stiffness parameters decreased, albeit disproportionately in magnitude, with increasing percent loss of cross-sectional area. Conversely, mean stress at the residual area (determined using remaining intact area at the laceration cross section) exhibited a marked increase in stress concentration beginning at 47.2% laceration using both specified load and constant strain analyses. The marked increase in stress concentration beginning near 50% laceration provides mechanical insight into the 50% rule. Additionally, a drastic decrease in viscoelastic stress parameters after only an 8.2% laceration suggests that time-dependent mechanisms protecting tissues during impact loadings are highly compromised regardless of laceration size. PMID:23363212

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

2013-01-01

132

On muscle, tendon and high heels.  

PubMed

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

2010-08-01

133

Stretch responsiveness of Golgi tendon organs  

Microsoft Academic Search

1.This report describes experiments on Ib afferents from tendon organs of the de-efferented soleus in acutely prepared cats in which: a) contrast was made of responses to passive forces generated by a dynamic stretch and to active forces generated by stimulating either the muscle nerve or small ventral root filaments; and, b) responses to static and dynamic stretch were related

D. G. Stuart; G. E. Goslow; C. G. Mosher; R. M. Reinking

1970-01-01

134

[The history of flexor tendon surgery].  

PubMed

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

Chamay, A

1997-01-01

135

Engaging Stem Cells for Customized Tendon Regeneration  

PubMed Central

The need for a consistent therapeutic approach to tendon injury repair is long overdue. Patients with tendon microtears or full ruptures are eligible for a wide range of invasive and non invasive interventions, often subjectively decided by the physician. Surgery produces the best outcomes, and while studies have been conducted to optimize graft constructs and to track outcomes, the data from these studies have been inconclusive on the whole. What has been established is a clear understanding of healthy tendon architecture and the inherent process of healing. With this knowledge, tissue regeneration efforts have achieved immense progress in scaffold design, cell line selection, and, more recently, the appropriate use of cytokines and growth factors. This paper evaluates the plasticity of bone-marrow-derived stem cells and the elasticity of recently developed biomaterials towards tendon regeneration efforts. Mesenchymal stem cells (MSCs), hematopoietic progenitor cells, and poly(1,8-octanediol co-citrate) scaffolds (POC) are discussed in the context of established grafting strategies. With POC scaffolds to cradle the growth of MSCs and hematopoietic progenitor cells, developing a fibroelastic network guided by cytokines and growth factors may contribute towards consistent graft constructs, enhanced functionality, and better patient outcomes. PMID:22685473

Thaker, Hatim; Sharma, Arun K.

2012-01-01

136

Relationship between compressive loading and ECM changes in tendons  

PubMed Central

Summary Tendons are designed to absorb and transfer large amounts of tensile load. The well organised, strong yet flexible, extracellular matrix allows for this function. Many tendons are also subject to compressive loads, such as at the entheses, as the tendon wraps around bony protuberances or from internal compression during tensile loading or twisting. Tendinopathy, the clinical syndrome of pain and dysfunction in a tendon is usually the result of overload. However, it is not only the tensile overload that should be considered, as it has been shown that compressive loads change tendon structure and that combination loads can induce tendon pathology. This review summarises how load is detected by the tenocytes, how they respond to compressive load and the resulting extracellular matrix changes that occur. Understanding the effect of compression on tendon structure and function may provide directions for future matrix based interventions. PMID:23885340

Docking, Sean; Samiric, Tom; Scase, Ebonie; Purdam, Craig; Cook, Jill

2013-01-01

137

Blood supply of the flexor hallucis longus tendon with regard to dancer's tendinitis: injection and immunohistochemical studies of cadaver tendons.  

PubMed

The flexor hallucis longus is the most common site of lower extremity tendon disorders in ballet dancers. Reduced vascularity is an important factor contributing to tendon degeneration and rupture under strain. A study was conducted on the vascular pattern of the human flexor hallucis longus tendon with injection techniques and immunohistochemically by using antibodies against laminin. Blood supply arose from the posterior tibial and the medial plantar artery. Peritendinous blood vessels penetrated the tendon and anastomosed with a longitudinally oriented intratendinous network. Injection specimens and immunohistochemistry revealed one avascular zone in which the tendon passed behind the talus and a second in which the tendon wrapped around the first metatarsal head. These are the most typical areas for tendon degeneration and rupture. PMID:12956563

Petersen, Wolf; Pufe, Thomas; Zantop, Thore; Paulsen, Friedrich

2003-08-01

138

Compensatory muscle activation caused by tendon lengthening post-Achilles tendon rupture.  

PubMed

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

2013-04-23

139

Compensatory muscle activation caused by tendon lengthening post Achilles tendon rupture  

PubMed Central

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 month post-surgery along with 5 healthy controls via ultrasound. EMG was collected from the triceps surae muscles and tibialis anterior during over-ground 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

2013-01-01

140

Foot posture is associated with morphometry of the peroneus longus muscle, tibialis anterior tendon, and Achilles tendon.  

PubMed

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

2014-06-01

141

The Achilles tendon: fundamental properties and mechanisms governing healing  

PubMed Central

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

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

2014-01-01

142

Ligament reconstruction tendon interposition with mersilene augmentation.  

PubMed

Many surgical procedures have been described for the treatment of thumb basilar joint osteoarthritis. Augmentation of the standard ligament reconstruction tendon interposition procedure with the use of a Mersilene suture tape suspension-plasty, to recreate the stability provided by the anterior oblique ligament and increase pinch strength, will be described. Satisfaction with this procedure was evaluated through surveys completed by patients. In addition, independent physical assessments were performed to demonstrate stability, range of motion, and strength. PMID:21358518

Stein, Andrew J; Schofield, Jennifer L; Marsh, Mike; Paulo, Jerry

2011-03-01

143

An Artificial Tendon with Durable Muscle Interface  

PubMed Central

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

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

2010-01-01

144

Low level laser therapy in healing tendon  

NASA Astrophysics Data System (ADS)

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.

2005-11-01

145

[Isolated stapedius tendon ossification: a case report].  

PubMed

In this study, a case with bilateral isolated stapedius tendon ossification was reported, since it is a rare clinical condition. A 46-year-old female patient was admitted to our clinic with the complaint of bilateral hearing loss. Tympanic membrane was bilateral normal in color and appearance on otomicroscopic examination. Pure tone air bone gap was between 20-25 dB at 1 kHz and 4 kHz on audiogram bilaterally. Middle ear pressure was normal and stapedius reflex was negative bilaterally. Preoperative diagnosis was otosclerosis. Right exploratory tympanotomy was performed. Isolated stapedius tendon ossification was determined. Normal stapedius movement was achieved by cutting the tendon. Three months later, the same procedure was performed on the left ear. Pure tone air bone gap was bilateral 0 dB at 0.5 kHz, 1 kHz and 2 kHz, and 5-10 dB at 4 kHz on audiogram postoperatively. PMID:21417973

Ulkü, Ca?atay Han

2011-01-01

146

Ethanol treatment of tendon allografts: a potential HIV inactivating procedure  

Microsoft Academic Search

Summary.  \\u000a The penetration rate of ethanol in human tendons was studied to in order to define the conditions which were necessary to\\u000a achieve an inactivating concentration against the Human Immunodeficiency Virus (HIV) within the tendon. The rate of alcohol\\u000a penetration was found to be slow and did not differ with different types of tendons. An average ethanol concentration of 14%

M. Anastasescou; O. Cornu; X. Banse; J. König; A. Hassoun; C. Delloye

1998-01-01

147

Diagnosis and treatment of intraoperative popliteus tendon impingement.  

PubMed

Herein, we describe a simple, effective strategy for diagnosing and treating intraoperative popliteus tendon impingement during total knee arthroplasty (TKA). When lateral impingement is detected intraoperatively during TKA, manual isolation of the popliteus tendon can help determine the cause. Using this technique, the etiology of intraoperative lateral impingement during TKA was never misdiagnosed and the popliteus tendon was never unnecessarily released. The technique described allows for accurate diagnosis of intraoperative lateral impingement during TKA and the prevention of unnecessary popliteus resection. PMID:24474167

Kazakin, Anatoly; Nandi, Sumon; Bono, James

2014-12-01

148

Mechanical properties of the flexor digitorum profundus tendon attachment.  

PubMed

The current study was performed to determine the strength and rigidity of the intact flexor digitorum profundus (FDP) tendon attachment and compare the rigidity at the attachment site to the rigidity within a more proximal part of the tendon. Eight cadaveric index fingers were tested to failure of the FDP tendon. Lines were drawn on each tendon with India ink stain at the position of the attachment to bone and 5 mm and 10 mm proximally. Each test was recorded using a high resolution video camera. A minimum of six images per test were used for analysis of tissue deformation. The centroid of each line was computationally identified to characterize the deformation of the tendon between the lines. Force vs. deformation curves were generated for the 5 mm region representing the tendon attachment and the 5 mm region adjacent to the attachment. Stiffness measurements were generated for each curve, and normalized by the initial length to determine the rigidity. The failure strength ranged from 263 N to 548 N, with rigidity values ranging from 2201 N/(mm/mm) to 8714 N/(mm/mm) and from 3459 N/(mm/mm) to 6414 N/(mm/mm) for the attachment and the tendon proximal to the attachment, respectively. The rigidity did not vary significantly between the attachment and proximal tendon based on a Wilcoxon signed rank test (p?=?0.2). The measured strength and rigidity establish biomechanical properties for the FDP tendon attachment to bone. PMID:24426675

Felder, Jerrod J; Guseila, Loredana M; Saranathan, Archana; Shary, Timothy J; Lippitt, Steven B; Elias, John J

2013-12-01

149

Mechanical characteristics of native tendon slices for tissue engineering scaffold  

PubMed Central

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

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

2014-01-01

150

Tendon transfer options in managing the adult flexible flatfoot.  

PubMed

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

2012-06-01

151

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

PubMed Central

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

2013-01-01

152

Multilayered electrospun scaffolds for tendon tissue engineering.  

PubMed

Full-thickness rotator cuff tears are one of the most common causes of shoulder pain in people over the age of 65. High retear rates and poor functional outcomes are common after surgical repair, and currently available extracellular matrix scaffold patches have limited abilities to enhance new tendon formation. In this regard, tissue-engineered scaffolds may provide a means to improve repair of rotator cuff tears. Electrospinning provides a versatile method for creating nanofibrous scaffolds with controlled architectures, but several challenges remain in its application to tissue engineering, such as cell infiltration through the full thickness of the scaffold as well as control of cell growth and differentiation. Previous studies have shown that ligament-derived extracellular matrix may enhance differentiation toward a tendon or ligament phenotype by human adipose stem cells (hASCs). In this study, we investigated the use of tendon-derived extracellular matrix (TDM)-coated electrospun multilayered scaffolds compared to fibronectin (FN) or phosphate-buffered saline (PBS) coating for use in rotator cuff tendon tissue engineering. Multilayered poly(?-caprolactone) scaffolds were prepared by sequentially collecting electrospun layers onto the surface of a grounded saline solution into a single scaffold. Scaffolds were then coated with TDM, FN, or PBS and seeded with hASCs. Scaffolds were maintained without exogenous growth factors for 28 days in culture and evaluated for protein content (by immunofluorescence and biochemical assay), markers of tendon differentiation, and tensile mechanical properties. The collagen content was greatest by day 28 in TDM-scaffolds. Gene expression of type I collagen, decorin, and tenascin C increased over time, with no effect of scaffold coating. Sulfated glycosaminoglycan and dsDNA contents increased over time in culture, but there was no effect of scaffold coating. The Young's modulus did not change over time, but yield strain increased with time in culture. Histology demonstrated cell infiltration through the full thickness of all scaffolds and immunofluorescence demonstrated greater expression of type I, but not type III collagen through the full thickness of the scaffold in TDM-scaffolds compared to other treatment groups. Together, these data suggest that nonaligned multilayered electrospun scaffolds permit tenogenic differentiation by hASCs and that TDM may promote some aspects of this differentiation. PMID:23808760

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

2013-12-01

153

Multilayered Electrospun Scaffolds for Tendon Tissue Engineering  

PubMed Central

Full-thickness rotator cuff tears are one of the most common causes of shoulder pain in people over the age of 65. High retear rates and poor functional outcomes are common after surgical repair, and currently available extracellular matrix scaffold patches have limited abilities to enhance new tendon formation. In this regard, tissue-engineered scaffolds may provide a means to improve repair of rotator cuff tears. Electrospinning provides a versatile method for creating nanofibrous scaffolds with controlled architectures, but several challenges remain in its application to tissue engineering, such as cell infiltration through the full thickness of the scaffold as well as control of cell growth and differentiation. Previous studies have shown that ligament-derived extracellular matrix may enhance differentiation toward a tendon or ligament phenotype by human adipose stem cells (hASCs). In this study, we investigated the use of tendon-derived extracellular matrix (TDM)-coated electrospun multilayered scaffolds compared to fibronectin (FN) or phosphate-buffered saline (PBS) coating for use in rotator cuff tendon tissue engineering. Multilayered poly(?-caprolactone) scaffolds were prepared by sequentially collecting electrospun layers onto the surface of a grounded saline solution into a single scaffold. Scaffolds were then coated with TDM, FN, or PBS and seeded with hASCs. Scaffolds were maintained without exogenous growth factors for 28 days in culture and evaluated for protein content (by immunofluorescence and biochemical assay), markers of tendon differentiation, and tensile mechanical properties. The collagen content was greatest by day 28 in TDM-scaffolds. Gene expression of type I collagen, decorin, and tenascin C increased over time, with no effect of scaffold coating. Sulfated glycosaminoglycan and dsDNA contents increased over time in culture, but there was no effect of scaffold coating. The Young's modulus did not change over time, but yield strain increased with time in culture. Histology demonstrated cell infiltration through the full thickness of all scaffolds and immunofluorescence demonstrated greater expression of type I, but not type III collagen through the full thickness of the scaffold in TDM-scaffolds compared to other treatment groups. Together, these data suggest that nonaligned multilayered electrospun scaffolds permit tenogenic differentiation by hASCs and that TDM may promote some aspects of this differentiation. PMID:23808760

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

2013-01-01

154

Repair of Achilles tendon defect with autologous ASCs engineered tendon in a rabbit model.  

PubMed

Adipose derived stem cells (ASCs) are an important cell source for tissue regeneration and have been demonstrated the potential of tenogenic differentiation in vitro. This study explored the feasibility of using ASCs for engineered tendon repair in vivo in a rabbit Achilles tendon model. Total 30 rabbits were involved in this study. A composite tendon scaffold composed of an inner part of polyglycolic acid (PGA) unwoven fibers and an outer part of a net knitted with PGA/PLA (polylactic acid) fibers was used to provide mechanical strength. Autologous ASCs were harvested from nuchal subcutaneous adipose tissues and in vitro expanded. The expanded ASCs were harvested and resuspended in culture medium and evenly seeded onto the scaffold in the experimental group, whereas cell-free scaffolds served as the control group. The constructs of both groups were cultured inside a bioreactor under dynamic stretch for 5 weeks. In each of 30 rabbits, a 2 cm defect was created on right side of Achilles tendon followed by the transplantation of a 3 cm cell-seeded scaffold in the experimental group of 15 rabbits, or by the transplantation of a 3 cm cell-free scaffold in the control group of 15 rabbits. Animals were sacrificed at 12, 21 and 45 weeks post-surgery for gross view, histology, and mechanical analysis. The results showed that short term in vitro culture enabled ASCs to produce matrix on the PGA fibers and the constructs showed tensile strength around 50 MPa in both groups (p > 0.05). With the increase of implantation time, cell-seeded constructs gradually form neo-tendon and became more mature at 45 weeks with histological structure similar to that of native tendon and with the presence of bipolar pattern and D-periodic structure of formed collagen fibrils. Additionally, both collagen fibril diameters and tensile strength increased continuously with significant difference among different time points (p < 0.05). In contrast, cell-free constructs failed to form good quality tendon tissue with fibril structure observable only at 45 weeks. There were significant differences in both collagen fibril diameter and tensile strength between two groups at all examined time points (p < 0.05). The results of this study support that ASCs are likely to be a potential cell source for in vivo tendon engineering and regeneration. PMID:25069604

Deng, Dan; Wang, Wenbo; Wang, Bin; Zhang, Peihua; Zhou, Guangdong; Zhang, Wen Jie; Cao, Yilin; Liu, Wei

2014-10-01

155

In situ microdialysis in tendon tissue: high levels of glutamate, but not prostaglandin E2 in chronic Achilles tendon pain  

Microsoft Academic Search

This investigation was to our knowledge the first to use the microdialysis technique to study concentrations of substances\\u000a in a human tendon. In four patients (mean age 40.7 years) with a painful nodule in the Achilles tendon (chronic Achilles tendinosis)\\u000a and in five controls (mean age 37.2 years) with normal Achilles tendons (confirmed by ultrasonography) the local concentrations\\u000a of glutamate

H. Alfredson; K. Thorsen; R. Lorentzon

1999-01-01

156

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

PubMed

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

2011-03-01

157

All-Arthroscopic Suprapectoral Long Head of Biceps Tendon Tenodesis With Interference Screw-Like Tendon Fixation After Modified Lasso-Loop Stitch Tendon Securing  

PubMed Central

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. PMID:23766976

Patzer, Thilo; Kircher, Jorn; Krauspe, Ruediger

2012-01-01

158

Ultrashort echo imaging of cyclically loaded rabbit patellar tendon.  

PubMed

Tendinopathy affects individuals who perform repetitive joint motion. Magnetic resonance imaging (MRI) is frequently used to qualitatively assess tendon health, but quantitative evaluation of inherent MRI properties of loaded tendon has been limited. This study evaluated the effect of cyclic loading on [Formula: see text] values of fresh and frozen rabbit patellar tendons using ultra short echo (UTE) MRI. Eight fresh and 8 frozen rabbit lower extremities had MR scans acquired for tendon [Formula: see text] evaluation. The tendons were then manually cyclically loaded for 100 cycles to 45N at approximately 1Hz. The MR scanning was repeated to reassess the [Formula: see text] values. Analyses were performed to detect differences of tendon [Formula: see text] values between fresh and frozen samples prior to and after loading, and to detect changes of tendon [Formula: see text] values between the unloaded and loaded configurations. No difference of [Formula: see text] was found between the fresh and frozen samples prior to or after loading, p=0.8 and p=0.1, respectively. The tendons had significantly shorter [Formula: see text] values, p=0.023, and reduced [Formula: see text] variability, p=0.04, after cyclic loading. Histologic evaluation confirmed no induced tendon damage from loading. Shorter [Formula: see text] , from stronger spin-spin interactions, may be attributed to greater tissue organization from uncrimping of collagen fibrils and lateral contraction of the tendon during loading. Cyclic tensile loading of tissue reduces patellar tendon [Formula: see text] values and may provide a quantitative metric to assess tissue organization. PMID:25234349

Koff, Matthew F; Pownder, Sarah L; Shah, Parina H; Yang, Lim Wei; Potter, Hollis G

2014-10-17

159

MAC-EYE: a Tendon Driven Fully Embedded Robot Eye  

E-print Network

MAC-EYE: a Tendon Driven Fully Embedded Robot Eye Dario Biamino, Giorgio Cannata, Marco Maggiali the possibility of designing a robot eye with kinematics and actuation similar to those of the human eye. In particular, we tried to exploit the spherical shape of the eye and to study the feasibility of a tendon based

Cannata, Giorgio

160

Granuloma formation secondary to Achilles tendon repair with nonabsorbable suture  

PubMed Central

INTRODUCTION Several complications can be observed after Achilles tendon repairs. In this study we aimed to report granuloma formation secondary to Achilles tendon repair with Ethibond (Ethicon INC, Somerville, New Jersey) suture. PRESENTATION OF CASE A 31 year-old man operated for Achilles tendon rupture. The Ethibond suture was used for primary repair. The patient attended to polyclinic with the complaints of swelling and discharge around the operation site four months after operation. A mass around distal portion of the Achilles tendon was detected. The granulomatous tissue was excised. Inside the mass Ethibond suture was detected. On histopathologic examination, typical findings of the foreign body reaction were observed. No microorganism was cultivated in the tissue culture. The patient has no complaint on the twelfth month control after surgery. DISCUSSION The results of primary repair of Achilles tendon are good but several complications were reported. In tendon repairs generally nonabsorbable sutures are used. The Ethibond is nonabsorbable, braided suture. In the literature, granuloma formations secondary to the suture materials such as polygylactine and braided polyethylen–polyester after Achilles tendon repair were reported but granuloma secondary to the Ethibond is very rare. CONCLUSION Although Ethibond suture is a strong and safe material for Achilles tendon repairs it may cause soft tissue problems such as granuloma. PMID:25212905

Kara, Adnan; Celik, Haluk; Seker, Ali; Uysal, Mehmet Ali; Uzun, Metin; Malkoc, Melih

2014-01-01

161

Mechanical strength of repairs of the hip piriformis tendon  

Microsoft Academic Search

Mechanical properties of repairs of the piriformis tendon to the proximal femur were examined in a cadaveric model. Four constructs were separately tested: a suture anchor in the proximal femur, the anchor to suture interface, the suture in tendon interface, and a bone bridge style repair. The weakest interface was the anchor in the bone in cases in which the

Paul S Robinson; Rick Placide; Louis J Soslowsky; Christopher T Born

2004-01-01

162

Ultrasonography of chronic tendon injuries in the groin  

Microsoft Academic Search

Ultrasonography was used in the diagnosis of 36 pa tients with chronic groin pain localized to the tendons of the rectus abdominis, rectus femoris, adductor mus cles, hamstring muscles, and the gluteal muscles. Ab normal findings, such as focal sonolucent areas and discontinuity of tendon fibers, that are indicative of nonhealed partial ruptures were found in 28 patients. These findings

Peter Kälebo; Jon Karlsson; Leif Sward; Lars Peterson

1992-01-01

163

Mechanical model of a single tendon finger  

NASA Astrophysics Data System (ADS)

The mechanical model of a single tendon three phalanxes finger is presented. By means of the model both kinematic and dynamical behavior of the finger itself can be studied. This finger is a part of a more complex mechanical system that consists in a four finger grasping device for robots or in a five finger human hand prosthesis. A first prototype has been realized in our department in order to verify the real behavior of the model. Some results of both kinematic and dynamical behavior are presented.

Rossi, Cesare; Savino, Sergio

2013-10-01

164

Continuum model of tendon pathology - where are we now?  

PubMed Central

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. PMID:23837792

McCreesh, Karen; Lewis, Jeremy

2013-01-01

165

Specialisation of extracellular matrix for function in tendons and ligaments  

PubMed Central

Summary Tendons and ligaments are similar structures in terms of their composition, organisation and mechanical properties. The distinction between them stems from their anatomical location; tendons form a link between muscle and bone while ligaments link bones to bones. A range of overlapping functions can be assigned to tendon and ligaments and each structure has specific mechanical properties which appear to be suited for particular in vivo function. The extracellular matrix in tendon and ligament varies in accordance with function, providing appropriate mechanical properties. The most useful framework in which to consider extracellular matrix differences therefore is that of function rather than anatomical location. In this review we discuss what is known about the relationship between functional requirements, structural properties from molecular to gross level, cellular gene expression and matrix turnover. The relevance of this information is considered by reviewing clinical aspects of tendon and ligament repair and reconstructive procedures. PMID:23885341

Birch, Helen L.; Thorpe, Chavaunne T.; Rumian, Adam P.

2013-01-01

166

Management of Flexor Tendon Lacerations in the Hand  

PubMed Central

Flexor tendon injuries in the hand present a real challenge in treatment. Poorly chosen or poorly executed treatment may lead to a functionless finger at best, impairing total hand function. A variety of approaches to treatment of flexor tendon injuries is available to the specially trained surgeon and a particular method is selected based on the merits of the case in question. Primary tendon repair is a viable choice under the proper conditions, while delayed primary repair allows a somewhat broader application of this technique. Flexor tendon grafting remains a very useful operation for the surgeon caring for tendon injuries of the hand. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:359822

Rankin, Edward A.

1978-01-01

167

Human patellar tendon stiffness is restored following graft harvest for anterior cruciate ligament surgery.  

PubMed

Minimising post-operative donor site morbidity is an important consideration when selecting a graft for surgical reconstruction of the torn anterior cruciate ligament (ACL). One of the most common procedures, the bone-patellar tendon-bone (BPTB) graft involves removal of the central third from the tendon. However, it is unknown whether the mechanical properties of the donor site (patellar tendon) recover. The present study investigated the mechanical properties of the human patellar tendon in 12 males (mean+/-S.D. age: 37+/-14 years) who had undergone surgical reconstruction of the ACL using a BPTB graft between 1 and 10 years before the study (operated knee; OP). The uninjured contralateral knee served as a control (CTRL). Patellar tendon mechanical properties were assessed in vivo combining dynamometry with ultrasound imaging. Patellar tendon stiffness was calculated from the gradient of the tendon's force-elongation curve. Tendon stiffness was normalised to the tendon's dimensions to obtain the tendon's Young's modulus. Cross-sectional area (CSA) of OP patellar tendons was larger by 21% than CTRL tendons (P<0.01). Patellar tendon stiffness was not significantly different between OP and CTRL tendons, but the Young's modulus was lower by 24% in OP tendons (P<0.01). A compensatory enlargement of the patellar tendon CSA, presumably due to scar tissue formation, enabled a recovery of tendon stiffness in the OP tendons. The newly formed tendon tissue had inferior properties as indicated by the reduced tendon Young's modulus, but it increased to a level that enabled recovery of tendon stiffness. PMID:19268289

Reeves, Neil D; Maganaris, Constantinos N; Maffulli, Nicola; Rittweger, Joern

2009-05-11

168

Influence of neglecting the curved path of the Achilles tendon on Achilles tendon length change at various ranges of motion.  

PubMed

Achilles tendon length has been measured using a straight-line model. However, this model is associated with a greater measurement error compared with a curved-line model. Therefore, we examined the influence of neglecting the curved path of the Achilles tendon on its length change at various ranges of motion. Ten male subjects participated in this study. First, the location of the Achilles tendon was confirmed by using ultrasonography, and markers were attached on the skin over the Achilles tendon path. Then, the three-dimensional coordinates of each marker at dorsiflexion (DF) 15°, plantarflexion (PF) 0°, PF15°, and PF30° were obtained. Achilles tendon length in the curved-line model was calculated as the sum of the distances among each marker. On the other hand, Achilles tendon length in the straight-line model was calculated as the straight distance between the two most proximal and distal markers projected onto the sagittal plane. The difference of the Achilles tendon length change between curved-line and straight-line models was calculated by subtracting the Achilles tendon length change obtained in curved-line model from that obtained in straight-line model with three different ranges of motion (i.e., PF0°, PF15°, and PF30° from DF15°, respectively). As a result, the difference in Achilles tendon length change between the two models increased significantly as the range of motion increased. In conclusion, neglecting the curved path of the Achilles tendon induces substantial overestimation of its length change when the extent of ankle joint angle change is large. PMID:25303951

Fukutani, Atsuki; Hashizume, Satoru; Kusumoto, Kazuki; Kurihara, Toshiyuki

2014-10-01

169

Estimation of tendon slack lengths of quadriceps based on a least squares optimization  

Microsoft Academic Search

Based on the force transfer relationship from muscle to tendon, a chart determining a normalized tendon force is developed. The experimental data of knee extension moment obtained at maximum isometric contractions are prepared to characterize one's musculo-tendon properties. An optimization algorithm is introduced, which searches the tendon slack lengths of quadriceps by minimizing the differences of calculated knee extension moment

Yoonsu Nam; Woo Eun Lee; Tai Jun Yoon

2008-01-01

170

Establishment of tendon-derived cell lines exhibiting pluripotent mesenchymal stem cell-like property  

Microsoft Academic Search

Development of the musculoskeletal system requires coordinated formation of distinct types of tissues, including bone, cartilage, muscle, and tendon. Compared to muscle, cartilage, and bone, cellular and molecular bases of tendon development have not been well understood due to the lack of tendon cell lines. The purpose of this study was to establish and characterize tendon cell lines. Three clonal

R Salingcarnboriboon; H Yoshitake; K Tsuji; M Obinata; T Amagasa; A Nifuji; M Noda

2003-01-01

171

Transcriptomic analysis of mouse limb tendon cells during development.  

PubMed

The molecular signals driving tendon development are not fully identified. We have undertaken a transcriptome analysis of mouse limb tendon cells that were isolated at different stages of development based on scleraxis (Scx) expression. Microarray comparisons allowed us to establish a list of genes regulated in tendon cells during mouse limb development. Bioinformatics analysis of the tendon transcriptome showed that the two most strongly modified signalling pathways were TGF-? and MAPK. TGF-?/SMAD2/3 gain- and loss-of-function experiments in mouse limb explants and mesenchymal stem cells showed that TGF-? signalling was sufficient and required via SMAD2/3 to drive mouse mesodermal stem cells towards the tendon lineage ex vivo and in vitro. TGF-? was also sufficient for tendon gene expression in late limb explants during tendon differentiation. FGF does not have a tenogenic effect and the inhibition of the ERK MAPK signalling pathway was sufficient to activate Scx in mouse limb mesodermal progenitors and mesenchymal stem cells. PMID:25249460

Havis, Emmanuelle; Bonnin, Marie-Ange; Olivera-Martinez, Isabel; Nazaret, Nicolas; Ruggiu, Mathilde; Weibel, Jennifer; Durand, Charles; Guerquin, Marie-Justine; Bonod-Bidaud, Christelle; Ruggiero, Florence; Schweitzer, Ronen; Duprez, Delphine

2014-10-01

172

The "turtleneck" pulley plasty for finger flexor tendon repair.  

PubMed

Injuries to the flexor tendons are frequent. Even when correctly treated, they can cause a loss of mobility of the digits secondary to postoperative adhesions. Further, conflicts between the tendon suture and the pulleys can limit the range of motion of the tendon and the flexion of the fingers. We propose a new pulley plasty that permits immediate retraining and avoids conflict with the tendon suture. Ten patients underwent surgery for a tendon injury in zone II, with no lesions of the associated pedicles. The tendons were repaired by a 4-strand stitch technique associated with a continuous peritendinous suture. Pulley plasty was systematically performed on A2, A4, or both. Eight patients recovered a satisfactory range of motion with a finger to palm distance of <1 cm, and 2 others with a distance of <2 cm. Two tenolyses were performed, for which no secondary reconstruction of the pulleys was necessary. This plasty technique is simple to carry out, reliable, and reproducible. Because it facilitates tendon repair and reinforces the existing pulleys, it permits immediate retraining and controlled active mobilization. PMID:24275761

Goubier, Jean-Noel; Lafosse, Thibault; Teboul, Frédéric

2014-03-01

173

The tendon injury response is influenced by decorin and biglycan.  

PubMed

Defining the constituent regulatory molecules in tendon is critical to understanding the process of tendon repair and instructive to the development of novel treatment modalities. The purpose of this study is to define the structural, expressional, and mechanical changes in the tendon injury response, and elucidate the roles of two class I small leucine-rich proteoglycans (SLRPs). We utilized biglycan-null, decorin-null and wild type mice with an established patellar tendon injury model. Mechanical testing demonstrated functional changes associated with injury and the incomplete recapitulation of mechanical properties after 6 weeks. In addition, SLRP deficiency influenced the mechanical properties with a marked lack of improvement between 3 and 6 weeks in decorin-null tendons. Morphological analyses of the injury response and role of SLRPs demonstrated alterations in cell density and shape as well as collagen alignment and fibril structure resulting from injury. SLRP gene expression was studied using RT-qPCR with alterations in expression associated with the injured tendons. Our results show that in the absence of biglycan initial healing may be impaired while in the absence of decorin later healing is clearly diminished. This suggests that biglycan and decorin may have sequential roles in the tendon response to injury. PMID:24072490

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

2014-03-01

174

Allograft anterior tibialis tendon with bioabsorbable interference screw fixation in anterior cruciate ligament reconstruction  

Microsoft Academic Search

For a variety of reasons, bone–patellar tendon–bone and Achilles tendon allografts have been used more commonly in anterior cruciate ligament reconstruction. Soft-tissue allografts used mainly are the semitendinosus, gracilis, and occasionally the quadriceps tendons. The anterior tibialis tendon is a thick, strong tendon that can be prepared with one doubling of the graft, has a large cross-sectional area, and has

David N. M. Caborn; Jeffrey B. Selby

2002-01-01

175

Minimally invasive surgery of the achilles tendon.  

PubMed

Minimally invasive surgical techniques for pathologies of the Achilles tendon (AT) hold the promise to decrease perioperative morbidity, allow faster recovery times, shorten hospital stays, and improve functional outcomes when compared with open procedures, which can lead to difficulty with wound healing because of the tenuous blood supply and increased chance of wound breakdown and infection. This article presents recent advances in the field of minimally invasive AT surgery for tendinopathy, acute ruptures, and chronic tears. All of the techniques described in this article are inexpensive and do not require highly specialized equipment and training. Future randomized controlled trials are required to address the issue of the comparison between open versus minimally invasive AT surgery. PMID:19773054

Maffulli, Nicola; Longo, Umile Giuseppe; Oliva, Francesco; Ronga, Mario; Denaro, Vincenzo

2009-10-01

176

Cellular therapy in bone-tendon interface regeneration  

PubMed Central

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

Rothrauff, Benjamin B; Tuan, Rocky S

2014-01-01

177

Measuring Achilles tendon mechanical properties: a reliable, noninvasive method.  

PubMed

The purpose of this technical report is to describe a cost-effective and highly reliable methodology to measure mechanical and material properties of the Achilles tendon. Subjects are positioned on an isokinetic dynamometer time synchronized to a diagnostic ultrasound device. A tendon fascicle distal to the soleus is visualized during a ramped isometric maximal plantarflexion contraction. Excursion of the fascicle and tendon torque output yield a force-elongation curve in which mechanical characteristics and material properties are derived. Excellent intrasession and intersession reliabilities were observed for both the dynamometer (intraclass correlation coefficient [ICC] 0.99, 0.95) and excursion (ICC 0.99, 0.93) measures. Practical applications for this methodology include examination of training regimes for optimal tendon adaptation and rehabilitation in the presence of tendinopathy. PMID:22561974

Joseph, Michael F; Lillie, Kurtis R; Bergeron, Daniel J; Denegar, Craig R

2012-08-01

178

A model of muscle-tendon function in human walking  

E-print Network

In order to motivate the design of legged machines that walk as humans do, this thesis investigates how leg muscles and tendons work mechanically during level-ground human walking at self-selected speeds. I hypothesize ...

Endo, Ken, Ph. D. Massachusetts Institute of Technology

2012-01-01

179

Fibroma of tendon sheath located within Kager's triangle.  

PubMed

The formation of a fibroma of the tendon sheath, a rare, slow-growing, benign tumor, usually occurs in the upper extremities of young adult males. We present an extremely rare case of a fibroma of the tendon sheath arising adjacent to the Achilles tendon within Kager's triangle in a 41-year-old female. The patient presented with progressive pain localized to the posterior aspect of the left ankle. Complete excision and histopathologic analysis of the fibroma were performed. The patient experienced an uneventful recovery after the intervention and had no evidence of recurrence after 3 months of follow-up. Fibroma of the tendon sheath should be included in the differential diagnosis when a patient presents with a painful soft tissue mass in Kager's triangle. PMID:24556488

Jacobs, Eva; Witlox, Marianne A; Hermus, Joris P S

2014-01-01

180

Uptake swelling and thermal expansion of CFRP tendons  

E-print Network

Carbon-fibre-reinforced polymer (CFRP) tendons can be used as a corrosion-resistant alternative to steel for reinforcing or prestressing concrete in aggressive marine environments. The design lives of many civil marine structures often span decades...

Scott, P.; Lees, Janet M.

2009-08-01

181

Subcutaneous Peroneus Longus Tendon Rupture Associated with OS Peroneum Fracture  

PubMed Central

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. PMID:24149615

Fujioka, Hiroyuki; Kokubu, Takeshi; Makino, Takeshi; Nagura, Issei; Maeda, Toshihisa; Kurosaka, Masahiro; Okuno, Hiroaki; Yamagiwa, Tokuyoshi; Tanaka, Juichi; Yoshiya, Shinichi

2009-01-01

182

Tendon and ligament adaptation to exercise, immobilization, and remobilization.  

PubMed

This study provides a theoretical and computational basis for understanding and predicting how tendons and ligaments adapt to exercise, immobilization, and remobilization. In a previous study, we introduced a model that described the growth and development of tendons and ligaments. In this study, we use the same model to predict changes in the cross-sectional area, modulus, and strength of tendons and ligaments due to increased or decreased loading. The model predictions are consistent with the results of experimental exercise and immobilization studies performed by other investigators. These results suggest that the same fundamental principles guide both development and adaptation. A basic understanding of these principles can contribute both to prevention of tendon and ligament injuries and to more effective rehabilitation when injury does occur. PMID:10850828

Wren, T A; Beaupré, G S; Carter, D R

2000-01-01

183

Mechanical properties of the patellar tendon in adults and children.  

PubMed

It is not currently known how the mechanical properties of human tendons change with maturation in the two sexes. To address this, the stiffness and Young's modulus of the patellar tendon were measured in men, women, boys and girls (each group, n=10). Patellar tendon force (F(pt)) was calculated from the measured joint moment during a ramped voluntary isometric knee extension contraction, the antagonist knee extensor muscle co-activation quantified from its electromyographical activity, and the patellar tendon moment arm measured from magnetic resonance images. Tendon elongation was imaged using the sagittal-plane ultrasound scans throughout the contraction. Tendon cross-sectional area was measured at rest from ultrasound scans in the transverse plane. Maximal F(pt) and tendon elongation were (mean+/-SE) 5453+/-307 N and 5+/-0.5 mm for men, 3877+/-307 N and 4.9+/-0.6 mm for women, 2017+/-170 N and 6.2+/-0.5 mm for boys and 2169+/-182 N and 5.9+/-0.7 mm for girls. In all groups, tendon stiffness and Young's modulus were examined at the level that corresponded to the maximal 30% of the weakest participant's F(pt) and stress, respectively; these were 925-1321 N and 11.5-16.5 MPa, respectively. Stiffness was 94% greater in men than boys and 84% greater in women than girls (p<0.01), with no differences between men and women, or boys and girls (men 1076+/-87 N/mm; women 1030+/-139 N/mm; boys 555+/-71 N/mm and girls 561.5+/-57.4 N/mm). Young's modulus was 99% greater in men than boys (p<0.01), and 66% greater in women than girls (p<0.05). There were no differences in modulus between men and women, or boys and girls (men 597+/-49 MPa; women 549+/-70 MPa; boys 255+/-42 MPa and girls 302+/-33 MPa). These findings indicate that the mechanical stiffness of tendon increases with maturation due to an increased Young's modulus and, in females due to a greater increase in tendon cross-sectional area than tendon length. PMID:20045111

O'Brien, Thomas D; Reeves, Neil D; Baltzopoulos, Vasilios; Jones, David A; Maganaris, Constantinos N

2010-04-19

184

Temporal response of canine flexor tendon to limb suspension  

PubMed Central

Tendon disuse, or stress deprivation, frequently accompanies clinical disorders and treatments, yet the metabolism of tendons subject to stress deprivation has rarely been investigated systematically. The effects of stress deprivation on canine flexor tendon were investigated in this study. One adult canine forepaw was suspended for 21 or 42 days. Control forepaws were collected from dogs that had no intervention on their limbs and paws. The expression of collagen I and III was not significantly altered in the tendons disused for 21 days but was significantly decreased at 42 days (P < 0.03). The expression of collagen II, aggrecan, decorin, and fibronectin was significantly decreased in the tendons in the suspended limbs at 21 days (P < 0.002) and further reduced at 42 days. With stress deprivation, the expression of matrix metalloproteinase 2 (MMP2) was significantly increased (P < 0.004) at 21 and 42 days. The expression of MMP3 was significantly decreased at 21 and 42 days (P < 0.03). The expression of MMP13 was not altered with stress deprivation at 21 and 42 days. The expression of MMP14 was significantly increased at 21 days (P = 0.0015) and returned to the control level at 42 days. Tissue inhibitor of metalloproteinase 1 (TIMP1) expression was decreased after the limbs were suspended for 42 days (P = 0.0043), but not 21 days. However, TIMP2 expression was not significantly different from control at 21 or 42 days. Furthermore, the cross-sectional area of the stress-deprived tendons at 42 days was decreased compared with the control group (P < 0.01). The intervention method in this study did not result in any alteration of stiffness of the tendon. Our study demonstrated that stress deprivation decreases the anabolic process and increases the catabolic process of extracellular matrix in flexor tendon. PMID:20947711

Thoreson, Andrew R.; Cha, Stephen S.; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C.

2010-01-01

185

Surgical Technique for Combined Dwyer Calcaneal Osteotomy and Peroneal Tendon Repair for Correction of Peroneal Tendon Pathology Associated with Cavus Foot Deformity  

Microsoft Academic Search

Peroneal tendon pathology is commonly seen in patients with underlying pes cavus. The Dwyer calcaneal osteotomy is a useful adjunctive procedure to address the heel varus component of the cavus foot deformity, especially in the presence of concomitant peroneal tendon pathology. The lateralizing heel osteotomy using a wedge resection can effectively reduce future stress on the repaired peroneal tendons, although

Troy J. Boffeli; Rachel C. Collier

186

Strain and elongation of the human semitendinosus muscle - tendon unit.  

PubMed

The semitendinosus (ST) consists of a long distal tendon and it is divided in two parts by a tendinous inscription (TI). The purpose of this study was to quantify strain and elongation of the TI and the distal tendon of ST. Fourteen subjects performed ramp isometric contractions of the knee flexors at 0°, 45° and 90° of knee flexion. Two ultrasound probes were used to visualize the displacement of the distal tendon and selected points across the TI and aponeuroses. Three-way analysis of variance designs indicated that: (a) strain and elongation of the ST distal muscle-tendon junction were higher than that of the aponeurosis - TI junction points (p < 0.05) (b) the long arm of the TI reach strain of 49.86 ± 7.77% which was significantly (p < 0.05) higher than that displayed by the short arm (28.35 ± 0.59%) (c) Strain of tendinous and TI-aponeuroses segments significantly increased from 90° to 0° of knee flexion while the inverse was observed for the TI arm length (p < 0.05). (d) Tendon strain was significantly higher than strain of the TI-aponeuroses segments at 45° and 90° of knee flexion while the opposite was observed at 0° of knee flexion. The arrangement of TI along ST length results in differential local strains, indicating that the mechanical properties of the ST muscle are affected by tendon, aponeuroses and tendinous inscription interactions. PMID:23992632

Kellis, Eleftherios; Patsika, Glykeria; Karagiannidis, Evaggelos

2013-12-01

187

Biomimetic Scaffold Design for Functional and Integrative Tendon Repair  

PubMed Central

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 underscore the clinical need for alternative grafting solutions. The two 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 future directions section. PMID:22244070

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

2012-01-01

188

The anatomical footprint of the Achilles tendon: a cadaveric study.  

PubMed

We dissected 12 fresh-frozen leg specimens to identify the insertional footprint of each fascicle of the Achilles tendon on the calcaneum in relation to their corresponding muscles. A further ten embalmed specimens were examined to confirm an observation on the retrocalcaneal bursa. The superficial part of the insertion of the Achilles tendon is represented by fascicles from the medial head of the gastrocnemius muscle, which is inserted over the entire width of the inferior facet of the calcaneal tuberosity. In three specimens this insertion was in continuity with the plantar fascia in the form of periosteum. The deep part of the insertion of the Achilles tendon is made of fascicles from the soleus tendon, which insert on the medial aspect of the middle facet of the calcaneal tuberosity, while the fascicles of the lateral head of the gastrocnemius tendon insert on the lateral aspect of the middle facet of the calcaneal tuberosity. A bicameral retrocalcaneal bursa was present in 15 of the 22 examined specimens. This new observation and description of the insertional footprint of the Achilles tendon and the retrocalcaneal bursa may allow a better understanding of the function of each muscular part of the gastrosoleus complex. This may have clinical relevance in the treatment of Achilles tendinopathies. PMID:25274919

Ballal, M S; Walker, C R; Molloy, A P

2014-10-01

189

Tendon Tissue Engineering: Progress, Challenges, and Translation to the Clinic  

PubMed Central

The tissue engineering field has made great strides in understanding how different aspects of tissue engineered constructs (TECs) and the culture process affect final tendon repair. However, there remain significant challenges in developing strategies that will lead to a clinically effective and commercially successful product. In an effort to increase repair quality, a better understanding of normal development, and how it differs from adult tendon healing, may provide strategies to improve tissue engineering. As tendon tissue engineering continues to improve, the field needs to employ more clinically relevant models of tendon injury such as degenerative tendons. We need to translate successes to larger animal models to begin exploring the clinical implications of our treatments. By advancing the models used to validate our TECs, we can help convince our toughest customer, the surgeon, that our products will be clinically efficacious. As we address these challenges in musculoskeletal tissue engineering, the field still needs to address the commercialization of products developed in the laboratory. TEC commercialization faces numerous challenges because each injury and patient is unique. This review aims to provide tissue engineers with a summary of important issues related to engineering tendon repairs and potential strategies for producing clinically successful products. PMID:21625053

Shearn, Jason T.; Kinneberg, Kirsten R.C.; Dyment, Nathaniel A.; Galloway, Marc T.; Kenter, Keith; Wylie, Christopher; Butler, David L.

2013-01-01

190

Principles and biomechanics of muscle tendon unit transfer: application in temporalis muscle tendon transposition for smile improvement in facial paralysis.  

PubMed

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

2013-02-01

191

Locking finger due to a partial laceration of the flexor digitorum superficialis tendon: a case report.  

PubMed

A 39-year-old woman sustained a small wound on the palm of her right hand, which quickly healed naturally; however, a month later pain and limited range of motion were noted in her right finger. Surgery revealed the radial half of the flexor digitorum superficialis (FDS) tendon was ruptured and formed a flap, which hooked at the entrance of the A1 pulley. The proximal stump was sutured to the remaining ulnar (normal) side of the FDS tendon. Locking occurs between the tendon flap and the tendon sheath; therefore, when there is no fibrous tendon sheath near the partially ruptured tendon, locking will not occur. PMID:25121943

Seki, Yasuhiro; Kuroda, Hiroshi

2014-01-01

192

Elbow tendinopathy and tendon ruptures: epicondylitis, biceps and triceps ruptures.  

PubMed

Lateral and medial epicondylitis are common causes of elbow pain in the general population, with the lateral variety being more common than the medial by a ratio reportedly ranging from 4:1 to 7:1. Initially thought to be an inflammatory condition, epicondylitis has ultimately been shown to result from tendinous microtearing followed by an incomplete reparative response. Numerous nonoperative and operative treatment options have been employed in the treatment of epicondylitis, without the emergence of a single, consistent, universally accepted treatment protocol. Tendon ruptures about the elbow are much less frequent, but result in more significant disability and loss of function. Distal biceps tendon ruptures typically occur in middle-aged males as a result of an event that causes a sudden, eccentric contraction of the biceps. Triceps tendon ruptures are exceedingly rare but usually have a similar etiology with a forceful eccentric contraction of the triceps that causes avulsion of the tendon from the olecranon. The diagnosis of these injuries is not always readily made. Complete ruptures of the biceps or triceps tendons have traditionally been treated surgically with good results. With regard to biceps ruptures, there continues to be debate about the best surgical approach, as well as the best method of fixation of tendon to bone. This article is not meant to be an exhaustive review of the broad topics of elbow tendinopathy and tendon ruptures, but rather is a review of recently published information on the topics that will assist the clinician in diagnosis and management of these conditions. PMID:19258160

Rineer, Craig A; Ruch, David S

2009-03-01

193

Extracellular matrix adaptation of tendon and skeletal muscle to exercise  

PubMed Central

The extracellular matrix (ECM) of connective tissues enables linking to other tissues, and plays a key role in force transmission and tissue structure maintenance in tendons, ligaments, bone and muscle. ECM turnover is influenced by physical activity, and both collagen synthesis and metalloprotease activity increase with mechanical loading. This can be shown by determining propeptide and proteinase activity by microdialysis, as well as by verifying the incorporation of infused stable isotope amino acids in biopsies. Local tissue expression and release of growth factors for ECM such as IGF-1, TGF-beta and IL-6 is enhanced following exercise. For tendons, metabolic activity (e.g. detected by positron emission tomography scanning), circulatory responses (e.g. as measured by near-infrared spectroscopy and dye dilution) and collagen turnover are markedly increased after exercise. Tendon blood flow is regulated by cyclooxygenase-2 (COX-2)-mediated pathways, and glucose uptake is regulated by specific pathways in tendons that differ from those in skeletal muscle. Chronic loading in the form of physical training leads both to increased collagen turnover as well as to some degree of net collagen synthesis. These changes modify the mechanical properties and the viscoelastic characteristics of the tissue, decrease its stress-susceptibility and probably make it more load-resistant. The mechanical properties of tendon fascicles vary within a given human tendon, and even show gender differences. The latter is supported by findings of gender-related differences in the activation of collagen synthesis with exercise. These findings may provide the basis for understanding tissue overloading and injury in both tendons and skeletal muscle. PMID:16637870

Kjær, Michael; Magnusson, Peter; Krogsgaard, Michael; Møller, Jens Boysen; Olesen, Jens; Heinemeier, Katja; Hansen, Mette; Haraldsson, Bjarki; Koskinen, Satu; Esmarck, Birgitte; Langberg, Henning

2006-01-01

194

Reconstruction of anterior cruciate ligaments with bone-patellar tendon-bone and achilles tendon allografts.  

PubMed

Two hundred fourteen patients had anterior cruciate ligament (ACL) reconstructions performed with banked freeze-dried or frozen allografts using an arthroscopic-assisted technique. Of these, 181 patients were available for follow-up testing and examination. Minimum follow-up time was four years (average, 57 months). All patients were evaluated by using KT-1000 arthrometer and Biodex testing as well as by physical examination. Final results were rated as satisfactory or unsatisfactory by using a modified Feagin knee scoring scale. Patients who were classified as good or excellent were considered to have satisfactory results. Those who were classified as fair or poor were considered to have unsatisfactory results. During the course of the study, 79% of the patients had satisfactory results. The percentage of patients with satisfactory results increased as the study progressed. The surgical technique was modified as new biomechanical principles were applied to ACL reconstruction. Rehabilitation of the patients was also progressively changed from conservative to aggressive. The authors attribute the improvement from 67% of patients with satisfactory results in 1984 to 85% in 1988 at least partially to these modifications. It was concluded that either frozen or freeze-dried aseptically excised and processed bone-patellar tendon-bone and Achilles tendon allografts can serve adequately for the reconstruction of ACLs. Complications may be reduced and clinical end results improved by adherence to an exact, reproducible surgical technique and an aggressive rehabilitation regimen. PMID:8194256

Levitt, R L; Malinin, T; Posada, A; Michalow, A

1994-06-01

195

The Effects of Dexamethasone on Human Patellar Tendon Stem Cells: Implications for Dexamethasone Treatment of Tendon Injury  

PubMed Central

Injection of Dexamethasone (Dex) is commonly used in clinics to treat tendon injury such as tendinopathy because of its anti-inflammatory capabilities. However, serious adverse effects have been reported as a result of Dex treatment, such as impaired tendon healing and tendon rupture. Using both in vitro and in vivo approaches, this study was to determine the effects of Dex treatment on the proliferation and differentiation of human tendon stem cells (hTSCs), which can directly impact tendon healing. We found that Dex treatment stimulated cell proliferation at lower concentrations (< 1000 nM), whereas a high concentration (1000 nM) decreased cell proliferation. Moreover, at all concentrations used (5, 10, 100, and 1000 nM), Dex treatment induced non-tenocyte differentiation of hTSCs, as evidenced by a change in cell shape, a nearly complete suppression of collagen type I expression, and an upregulation of non-tenocyte related genes (PPAR? and Sox-9), which was especially evident when higher concentrations (> 10 nM) of Dex were used. Implantation of Dex-treated hTSCs for a short time (3 weeks) resulted in the extensive formation of fatty tissues, cartilage-like tissues, and bony tissues. These findings suggest that Dex treatment in clinics may cause a paradoxical effect on the injured tendons it is supposed to treat: by inducing non-tenocyte differentiation of hTSCs, Dex treatment depletes the stem cell pool and leads to the formation of non-tendinous tissues (e.g. fatty and cartilage-like tissues), which make tendon susceptible to rupture. PMID:22886634

Zhang, Jianying; Keenan, Camille; Wang, James H-C.

2012-01-01

196

An investigation of tendon sheathing filler migration into concrete  

SciTech Connect

During some of the inspections at nuclear power plants with prestressed concrete containments, it was observed that the containments has experienced leakage of the tendon sheathing filler (i.e., streaks). The objective of this activity was to provide an indication of the extent of tendon sheathing filler leakage into the concrete and its affects on concrete properties. Literature was reviewed and concrete core samples were obtained from the Trojan Nuclear Plant and tested. The literature primarily addressed effects of crude or lubricating oils that are known to cause concrete damage. However, these materials have significantly different characteristics relative to the materials used as tendon sheathing fillers. Examination and testing of the concrete cores indicated that the appearance of tendon sheathing filler on the concrete surface was due to leakage from the conduits and its subsequent migration through cracks that were present. Migration of the tendon sheathing filler was confined to the cracks and there was no perceptible movement into the concrete. Results of compressive strength testing indicated that the concrete quality was consistent in the containment and that the strength had increased over 40% in 25.4 years relative to the average compressive strength at 28-days age.

Naus, D.J.; Oland, C.B. [Oak Ridge National Lab., TN (United States)

1998-03-01

197

Technical and biological modifications for enhanced flexor tendon repair.  

PubMed

Clinical outcomes after intrasynovial flexor tendon repair have been substantially improved over the past 2 decades through advances in tendon suture techniques and postoperative rehabilitation methods. Nevertheless, complications such as repair site elongation (i.e., gap formation) and rupture continue to occur frequently. Experimental studies have shown that repair site strength fails to increase in the first 3 weeks after tendon suture. After 3 weeks, the strength and rigidity of the repair site improve significantly, a process that continues for several months. Formation of a repair site gap during the early rehabilitation period has been shown to considerably delay the accrual of repair site strength over time. Thus, it is of prime importance that the method of tendon suture achieves and maintains a stiff and strong repair site during the early healing interval by maintaining close approximation of the tendon stumps and by stimulating, where possible, the intrinsic repair response. In this review, we describe recent efforts to enhance the integrity of the immature repair site. We focus on 2 major areas of advancement: surgical technique modifications and manipulation of the biologic and biochemical environment. PMID:20513584

Kim, H Mike; Nelson, Gregory; Thomopoulos, Stavros; Silva, Matthew J; Das, Rosalina; Gelberman, Richard H

2010-06-01

198

Long Head of the Biceps Tendon Allis Clamp Evaluation Technique  

PubMed Central

Disorders of the long head of the biceps brachii are a common finding in conjunction with other causes of shoulder pathology. Nonoperative means as first-line treatment are often successful; however, surgery can be indicated for refractory tendinopathy. There is debate as to the best surgical treatment of the long head of the biceps tendon (LHBT) with different types of arthroscopic and open techniques. The decision on what treatment option to perform is often made at the time of surgery after arthroscopic evaluation of the LHBT. Certain examples of tendon disease are easily visible intra-articularly; however, a large portion of the tendon is not intra-articular and not readily viewed during routine arthroscopy. This study describes a simple arthroscopic technique for evaluation of an increased portion of the LHBT using an Allis clamp. The clamp is inserted through the anterior portal, placed around the LHBT, and rotated such that the tendon is wrapped around itself, bringing the distal tendon into the joint for arthroscopic viewing. This procedure is a routine part of our assessment of the LHBT during arthroscopy. PMID:25276608

Parada, Stephen A.; Dilisio, Matthew F.; Miller, Lindsay R.; Higgins, Laurence D.

2014-01-01

199

77 FR 69508 - Inservice Inspection of Prestressed Concrete Containment Structures With Grouted Tendons  

Federal Register 2010, 2011, 2012, 2013

...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...

2012-11-19

200

Diclofenac Patch for Treatment of Mild to Moderate Tendonitis or Bursitis  

ClinicalTrials.gov

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

2008-08-05

201

Rest length and compliance of non-immobilised and immobilised rabbit soleus muscle and tendon  

Microsoft Academic Search

The first aim of this study was to measure the contributions of muscle and tendon to the total compliance of resting muscle-tendon\\u000a units. A second aim was to determine whether the decrease in muscle-tendon unit rest length produced by prolonged immobilisation\\u000a in a shortened position is mediated primarily by adaptations of the muscle or tendon. One ankle joint from each

R. D. Herbert; J. Crosbie

1997-01-01

202

Measurement of frog semitendinosus force, tendon load-deformation and load-strain properties  

Microsoft Academic Search

The authors previously studied the mechanics of the Rana pipiens semitendinosus (ST) muscle, assuming zero tendon compliance. The tendon of this muscle is relatively short, perhaps justifying the assumption. A study is reported here of the load-deformation and load-strain properties of these tendons. The tendon slack length was measured at 2.2 ?m. In this case, the muscle force was not

M. E. Leonard; R. L. Lieber

1989-01-01

203

The Achilles Tendon Insertion is Crescent-shaped: An In Vitro Anatomic Investigation  

Microsoft Academic Search

Anatomic and operative textbooks and current literature do not clearly describe the Achilles tendon interface to the calcaneal\\u000a tuberosity. We dissected 51 specimens to identify the detailed anatomy of the Achilles tendon insertion. Achilles tendon fascicles\\u000a expanded from the anterior aspect of the distal Achilles tendon over the retrocalcaneal bursa to the anterior part of the\\u000a Haglund’s tuberosity in nearly

Heinz Lohrer; Sabine Arentz; Tanja Nauck; Nadja V. Dorn-Lange; Moritz A. Konerding

2008-01-01

204

Cross-sectional anatomy of the bicipital tuberosity and biceps brachii tendon insertion: relevance to anatomic tendon repair.  

PubMed

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

2008-01-01

205

An Investigation of Tendon Corrosion-Inhibitor Leakage into Concrete  

SciTech Connect

During inspections performed at US nuclear power plants several years ago, some of the prestressed concrete containment had experienced leakage of the tendon sheathing filler. A study was conducted to indicate the extent of the leakage into the concrete and its potential effects on concrete properties. Concrete core samples were obtained from the Trojan Nuclear Plant. Examination and testing of the core samples indicated that the appearance of tendon sheathing filler on the surface was due to leakage of the filler from the conduits and its subsequent migration to the concrete surface through cracks that were present. Migration of the tendon sheathing filler was confined to the cracks with no perceptible movement into the concrete. Results of compressive strength tests indicated that the concrete quality was consistent in the containment and that the strength had increased relative to the strength at 28 days age.

Costello, J.F.; Naus, D.J.; Oland, C.B.

1999-07-05

206

Rupture of the peroneus tertius tendon in 27 horses  

PubMed Central

Abstract The purpose of the study was to identify factors influencing the outcome and prognosis of rupture of the tendon of the peroneus tertius muscle in 27 horses. Information on history, physical examination findings, diagnosis, treatment, and final outcome was summarized from medical records. Long-term follow-up information on horses was obtained by telephone survey. A stepwise logistic regression model was used to analyze factors influencing the outcome. Rupture occurred in the midbody of the tendon in 11 horses, at the insertion site in 11 horses, and at the origin in 2 horses. Overall, 18/23 (78.3%) horses returned to their previous level of exercise, 5/23 (21.7%) horses were euthanized due to persistent lameness. If the horse was racing at the time of injury or had an additional structure injured besides the peroneus tertius tendon, it was less likely to return to its intended use. PMID:16048009

2005-01-01

207

Could Ossification of the Achilles Tendon Have a Hereditary Component?  

PubMed Central

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? PMID:23738172

Cortbaoui, Chawki

2013-01-01

208

Subcoracoid impingement and subscapularis tendon: is there any truth?  

PubMed

Subcoracoid impingement and stenosis have been described related to anterior shoulder pain and subscapularis tendon tears, but the pathogenesis and related treatment of this condition has still not been explained properly. Variability of coracoid morphology has been described and both traumatic and iatrogenic factors can modify it. Some authors referred this to a primary narrow coracohumeral distance with different threshold values defined as increased risk factor for subscapularis and antero-superior RC tear; opposite theories stated that the stenosis is secondary to an anterosuperior translation of the humeral head toward the coracoid due to degenerative changes of the rotator cuff tendons. Limited coracoplasty can be performed when related risk factors are identified; however no clear consensus arises from specific literature review and extensive clinical and instrumental examination of the patient should be performed in order to identify specific risk factors for subscapularis tendon pathology and, subsequently, tailor the proper approach. PMID:23888292

Osti, Leonardo; Soldati, Francesco; Del Buono, Angelo; Massari, Leo

2013-04-01

209

Estimation of hamstring tendon slack length for knee flexor moment approximations  

Microsoft Academic Search

This paper presents a model to estimate hamstring tendon slack length for knee flexor moment approximations. The muscle force is very sensitive to the tendon slack length. To predict a tendon slack length, exact muscle parameters are needed. But it is difficult to measure all of the muscle parameters from human body. So we propose the algorithm which finds the

Hyun Woo Uhm; Han Soon Choi; Yoonsu Nam

2009-01-01

210

Estimation of tendon slack length of knee extension\\/flexion muscle  

Microsoft Academic Search

In this paper, we consider about a model to estimate the knee joint extension\\/flexion moment using the angle of the joints and EMG signal. We need exact muscle-tendon parameters for exact estimation of knee moment. But It is very difficult. The muscle force is sensitive to the tendon slack length. So, we developed the algorithm which finds the tendon slack

Woo-Eun Lee; Hyun-Woo Uhm; Yoon-Su Nam

2008-01-01

211

Is There a Role for Ultrasound and Electrical Stimulation Following Injury to Tendon and Nerve?  

Microsoft Academic Search

Ultrasound (US) and electrical stimulation have been widely used in hand therapy to promote recovery after nerve and tendon injuries. There is support for the use of low-dosage continuous wave and pulsed US for carpal tunnel syndrome and tendonitis. Iontophoresis with dexamethasone sodium phosphate can relieve pain in acute elbow tendonitis, but there is no support for phonophoresis for any

Susan L. Michlovitz

2005-01-01

212

Striated muscle fiber apoptosis after experimental tendon lesion in a rat model  

PubMed Central

Tendon lesions induce muscular atrophy, the nature of which has not yet been clearly related to lesion etiology and entity. In the present study, tendon and muscle alterations were assessed after experimental tendon lesion of the Infraspinatus muscle in young rats. The consequences of lesions differed on the basis of both extension and injured tissue vascularization, that is apoptosis and/or degeneration, differing mainly by energy demands: apoptosis requires high energy levels (proportional to vascular supply), but degeneration does not. It is well known that tendons are poorly supplied with blood compared with muscular masses, which are abundantly vascularized. Five weeks after tendon surgical section, tendon/muscle samples were taken for TUNEL and transmission electron microscopy. The structural results reported here identified different tendon/muscle alterations: degeneration of tendon without signs of apoptosis, and atrophy of muscle fibers due only to apoptosis. This led to the formulation of the following hypothetical sequence of events: a tendon lesion, not recovering quickly due to the poor tendon blood supply, results in degeneration of the injured tendon, which, in turn, induces a partial disuse of the muscle mass, which consequently atrophies (proportionally to the severity of tendon lesion) by striated muscular fiber apoptosis. The authors suggest that the different behavior of the two tissues depends on the marked difference in their vascularization. PMID:22881388

Palumbo, Carla; Rovesta, Claudio; Ferretti, Marzia

2012-01-01

213

A partially biodegradable material device for repair and reconstruction of injured tendons  

Microsoft Academic Search

We assessed the applicability of a partially biodegrad able synthetic material composed of polyglycolic acid (PGA) and dacron to repair or replace severely injured tendons. Adult rabbits underwent complete laceration and repair of one Achilles tendon. Group 1 (N = 8) had end to end tenorrhaphy with size 0 braided polyester suture, and Group 2 (N = 16) tendons were

William G. Rodkey; H. Edward Cabaud; John A. Feagin; Paul C. Perlik

1985-01-01

214

[Psoas haematoma due to irritation of the psoas tendon].  

PubMed

Irritation of the tendon of the musculus iliopsoas after total hip replacement is a rare complication. In connection with the irritation of the iliopsoas tendon only one case report of a psoas haematoma due to anticoagulation has been published. We assume that these kinds of haematomas are more frequent than described. We report on 2 cases of haematoma caused by an iliopsoas impingement after total hip replacement. In one case a lesion of the femoral nerve was observed. Surgical treatment was composed of the revision of the acetabular component. PMID:24129721

Lausmann, C; Mathonia, P; Plötz, W

2013-10-01

215

Ultrasound in the diagnosis of posterior tibial tendon pathology.  

PubMed

We retrospectively evaluated the effectiveness of ultrasonography as a diagnostic tool for investigating pathology in the posterior tibial tendon by comparing the preoperative ultrasonograms for 17 patients with their recorded surgical findings. In all cases, the surgical findings confirmed the ultrasonographic diagnoses: 3 inflammations, 4 partial tears, and 10 ruptures. Interestingly, two ruptures had been undiagnosed by magnetic resonance imaging. Ultrasonography, which seems to be a reliable means of visualizing the extent of pathology of the symptomatic posterior tibial tendon, may be a valuable tool in surgical planning. PMID:8886783

Miller, S D; Van Holsbeeck, M; Boruta, P M; Wu, K K; Katcherian, D A

1996-09-01

216

Mineralization of dentin, bone and tendon in vitro  

Microsoft Academic Search

Bovine dentin, bone, and tendon slices, and rat bone, readily mineralize to variable degrees after demineralization by (EDTA)\\u000a at pH 7.4, but they fail to mineralize after demineralzation with acetic acid (HAc) at pH 3.0. The demineralized dentin, but\\u000a neither bone nor tendon, contained organically bound phosphate. The EDTA-demineralized dentin contained less phosphate than\\u000a HAc-demineralized dentin. HAc-demineralized rat dentin contained

C. V. DeSteno; F. Feagin; W. T. Butler

1975-01-01

217

Abnormal tenocyte morphology is more prevalent than collagen disruption in asymptomatic athletes' patellar tendons.  

PubMed

This study investigated the prevalence of each of the four features of patellar tendinosis in asymptomatic athletic subjects undergoing patellar tendon anterior cruciate ligament (ACL) reconstruction. Fifty subjects (39 males and 11 females) undergoing ACL reconstruction using a patellar tendon graft were screened for previous tendon symptoms, training and playing history and had their patellar tendons examined with ultrasound prior to surgery. During surgery, a small piece of proximal posterocentral tendon was harvested, fixed and examined under light microscopy. Histopathological changes were graded for severity. Results demonstrate that 18 tendons were abnormal on light microscopy and 32 were normal. There were no differences between subjects with and without pathology in respect of training, recovery after surgery and basic anthropometric measures. Three tendons were abnormal on ultrasound but only one had proximal and central changes. Tendons showed a consistent series of changes. Tenocyte changes were found in all but one of the abnormal tendons. In all but one of the tendons with increased ground substance there were tenocyte changes, and collagen separation was always associated with both tenocyte changes and increased ground substance. No tendons demonstrated neovascularization. It appears that cellular changes must be present if there is an increase in ground substance, or collagen and vascular changes. Further research is required to confirm these findings. PMID:15013093

Cook, J L; Feller, J A; Bonar, S F; Khan, K M

2004-03-01

218

Fusimotor activity and the tendon jerk in the anaesthetised cat  

Microsoft Academic Search

This is a study of the tendon jerk reflex elicited by a brief stretch applied to the triceps surae muscle group in the chloralose-anaesthetised cat. The size of the recorded reflex depended on stretch parameters (optimum at 300 µm amplitude at a rate of 100 mm\\/s) and on how the muscle had been conditioned. A reflex elicited after a conditioning

S. A. Wood; D. L. Morgan; J. E. Gregory; U. Proske

1994-01-01

219

Bilateral patellar tendon disruption--a professional predisposition?  

PubMed Central

A healthy 37-year-old male carpet fitter sustained an injury to both knees while playing football. The clinical signs of patellar tendon disruption were not obvious because of gross skin thickening as a result of his profession, however, the diagnosis was confirmed by ultrasound scan. PMID:7894815

Sochart, D H; Shravat, B P

1994-01-01

220

Tendon organs as monitors of muscle damage from eccentric contractions  

Microsoft Academic Search

Eccentric contractions, where the active muscle is stretched, can lead to muscle damage. One of the signs of damage is a rise in the whole-muscle passive tension. Here we have asked, how many eccentric contractions are necessary to produce a measurable rise in passive tension and can this be detected by the muscle's tension sensors, the tendon organs? Responses of

J. E. Gregory; D. L. Morgan; U. Proske

2003-01-01

221

Ciprofloxacin-induced tendinopathy of the gluteal tendons.  

PubMed

Fluoroquinolone-induced tendinopathy most commonly affects the Achilles tendon; however, involvement of several other tendons has been described. This is a case report of ciprofloxacin-induced tendinopathy of the gluteal tendons with MRI findings. An obese 25-year-old woman with no significant past medical history was diagnosed with acute pyelonephritis and was treated with intravenous ciprofloxacin. Shortly after her first dose of ciprofloxacin, she developed severe left hip pain and decreased range of motion. MRI of the hips showed bilateral tendinopathy of the gluteal muscle insertion. A diagnosis of ciprofloxacin-induced tendinopathy was made based on her MRI and a Naranjo score of 7. Ciprofloxacin was stopped and her pain quickly resolved. Fluoroquinolones cause tendinopathy in 0.14 % to 0.4 % of patients using these agents. Fluoroquinolone-associated tendinopathy is a serious adverse reaction that can affect many tendons and should be considered in any patient presenting with new musculoskeletal complaints and in whom there is a history of fluoroquinolone use within the preceding 6 months. PMID:25047394

Shimatsu, Kaumakaokalani; Subramaniam, Somasundaram; Sim, Helen; Aronowitz, Paul

2014-11-01

222

Mineralized fibroma of the tendon sheath presenting as a bursitis.  

PubMed

We report on the clinical, imaging-including ultrasound, computed tomography, and magnetic resonance imaging-and histological features of a fibroma of the tendon sheath with mineralized chondroid and osseous metaplasia, presenting as a semimembranosus bursitis. The anatomical characteristics of the semimembranosus bursa are demonstrated by dissection in a cadaveric specimen and correlated with the imaging findings in our patient. PMID:18685844

Le Corroller, Thomas; Bouvier-Labit, Corinne; Sbihi, Abderrahmane; Champsaur, Pierre

2008-12-01

223

Wrist tendon forces during different dynamic wrist motions  

PubMed Central

Purpose A common treatment of arthritis of the first carpometacarpal joint requires all or a portion of the flexor carpi radialis tendon (FCR) to be used as an interpositional graft. The purpose of this study was to examine the in vitro tendon forces in six wrist flexor and extensors to determine if their force contribution changes during different dynamic wrist motions along with a specific application to the FCR. Methods Sixty two fresh frozen cadaver wrists were tested in a wrist joint motion simulator. During wrist flexion-extension, radioulnar deviation, dart throwing and circumduction motions, the peak and average tendon forces were determined for the extensor carpi ulnaris, extensor carpi radialis brevis and longus, abductor pollicis longus, flexor carpi radialis and flexor carpi ulnaris. Results During a dart throwing motion, the mean and peak FCR forces were statistically less than during the other 3 motions. Conversely, the mean and peak flexor carpi ulnaris forces were statistically greater during the dart throwing motion than during the other 3 motions. Discussion Patients who have undergone a surgical procedure in which all or a portion of the FCR has been harvested, may experience a decrease in wrist strength with wrist motion as the FCR tendon normally applies force during wrist motion. The motion least likely to be affected by such surgery is the dart throwing motion when the force on the remaining FCR is minimized. PMID:20353863

Werner, Frederick W.; Short, Walter H.; Palmer, Andrew K.; Sutton, Levi G.

2010-01-01

224

Three tendon transfer methods in reconstruction of ulnar nerve palsy  

Microsoft Academic Search

Purpose: This study was designed to investigate the efficacy of 3 different tendon transfer techniques in restoring grip strength, correcting claw hand deformity, and improving hand function after irreparable ulnar nerve palsy. Method: A total of 44 patients were assessed 14 to 96 months after surgery. Twenty-four patients were reconstructed with the flexor digitorum 4-tail (FDS 4-tail) procedure, 11 with

Türker Özkan; Ka?an Özer; Ayan Gülgönen

2003-01-01

225

Synthetic Collagen Fascicles for the Regeneration of Tendon Tissue  

E-print Network

that the resulting post-fabrication type-I collagen structure retains the essential phase behaviour, alignment and spectral characteristics of aligned native type-I collagen. We have also shown that both ovine tendon fibroblasts and human white blood cells in whole...

Kew, SJ; Gwynne, JH; Enea, D; Brooks, R; Rushton, N; Best, Serena Michelle; Cameron, Ruth Elizabeth

2012-01-01

226

Some effects of Bunnell suture on otherwise uninjured tendons in subhuman primates.  

PubMed

An experimental study was performed in rhesus monkeys (M. mulatta) to examine the contribution of Bunnell tendon suture to the production of postoperative tendon adhesions. It was found that Bunnell suture used with atraumatic technique caused a significant depression of in vitro tendon surface plasminogen activator activity, allowing the in vivo persistence and fibrous organization of fibrinous postoperative adhesions to sutured areas. Bunnell suture also produced coagulation necrosis of the sutured area of tendon. Collagen, which replaced the destroyed areas, was oriented randomly and frequently was continuous with surface tendon adhesions to surrounding connective tissues. Bunnell suture appears to be a cause of tendon adhesions in subhuman primates. The importance of fibrin and depressed local fibrinolysis in the relationship of tendon ischemia and adhesion formation is discussed. PMID:411189

Buckman, R F; Hufnagel, H V; Olivier, G; Buckman, P D; Zuidema, G D

1977-11-01

227

Age-related changes in mechanical properties of the Achilles tendon  

PubMed Central

The stiffness of a tendon, which influences muscular force transfer to the skeleton and increases during childhood, is dependent on its material properties and dimensions, both of which are influenced by chronic loading. The aims of this study were to: (i) determine the independent contributions of body mass, force production capabilities and tendon dimensions to tendon stiffness during childhood; and (ii) descriptively document age-related changes in tendon mechanical properties and dimensions. Achilles tendon mechanical and material properties were determined in 52 children (5–12 years) and 19 adults. Tendon stiffness and Young's modulus (YM) were calculated as the slopes of the force–elongation and stress-strain curves, respectively. Relationships between stiffness vs. age, mass and force, and between YM vs. age, mass and stress were determined by means of polynomial fits and multiple regression analyses. Mass was found to be the best predictor of stiffness, whilst stress was best related to YM (< 75 and 51% explained variance, respectively). Combined, mass and force accounted for up to 78% of stiffness variation. Up to 61% of YM variability could be explained using a combination of mass, stress and age. These results demonstrate that age-related increases in tendon stiffness are largely attributable to increased tendon loading from weight-bearing tasks and increased plantarflexor force production, as well as tendon growth. Moreover, our results suggest that chronic increases in tendon loading during childhood result in microstructural changes which increase the tendon's YM. Regarding the second aim, peak stress increased from childhood to adulthood due to greater increases in strength than tendon cross-sectional area. Peak strain remained constant as a result of parallel increases in tendon length and peak elongation. The differences in Achilles tendon properties found between adults and children are likely to influence force production, and ultimately movement characteristics, which should be explicitly examined in future research. PMID:22150089

Waugh, C M; Blazevich, A J; Fath, F; Korff, T

2012-01-01

228

Two-stage reconstruction for flexor tendon injuries in zone II using a silicone rod and pedicled sublimis tendon graft  

PubMed Central

We report the results of staged flexor tendon reconstruction in 12 patients (12 fingers) with neglected or failed primary repair of flexor tendon injuries in zone II. Injuries involved both flexor digitorum profundus (FDP) and flexor digitorum sublimis (FDS), with poor prognosis (Boyes grades II–IV). The procedure included placing a silicone rod and creating a loop between the FDP and FDS in the first stage and reflecting the latter as a pedicled graft through the pseudosheath created around the silicone rod in the second stage. At a mean follow-up of 18 months (range 12–30 months), results were assessed by clinical examination and questionnaire. The mean total active motion of these fingers was 188°. The mean power grip was 80.0% and pinch grip was 76% of the contralateral hand. The rate of excellent and good results was 75% according to the Buck-Gramcko scale. These results were better than the subjective scores given by the patients. Complications included postoperative hematoma in two, infection in one, silicone synovitis in one (after stage I) and three flexion contractures after stage II. This study confirmed the usefulness of two-stage flexor tendon reconstruction using the combined technique as a salvage procedure to restore flexor tendon function with a few complications. PMID:20924443

Abdul-Kader, Mohammed Heshmat; Amin, Mahmound A. M.

2010-01-01

229

Operative technique for human composite flexor tendon allograft procurement and engraftment.  

PubMed

Devastating volar hand injuries with significant damage to the pulley structures and fibro-osseous sheath, flexor tendons, and volar plates pose a major problem to the reconstructive hand surgeon. Despite advances in tendon handling, operative technique, and postoperative hand rehabilitation, patients who have undergone flexor tendon reconstruction are often plagued by chronic pain, stiffness, and decreased range of motion with resultant decreased ability to work and poor quality of life. Postoperative adhesion formation and lack of suitable donor material for tendon autograft are 2 fundamental problems that continue to challenge the hand surgeon. In 1967, Erle E. Peacock, Jr, described a technique of flexor tendon reconstruction using cadaveric composite flexor tendon allograft, which consisted of both the flexor digitorum profundus and superficialis tendons in their respective fibro-osseous sheaths consisting of the digital pulley structures and the underlying periosteum and volar plates. This technique never gained widespread acceptance due to concerns regarding tissue antigenicity, infectious disease transmission, and the rising popularity of the method of Hunter for silastic rod-based flexor tendon reconstruction initially described during the same period. With modern-day advances in tissue processing with acellularization and extensive donor screening for transmissible diseases, this technique should be revisited to address the reconstructive needs of patients with extensive volar soft tissue and tendon injury. Herein, we describe the operative technique of composite flexor tendon procurement and reconstruction with key modifications from the initial technique described by Peacock for improved composite construct elevation, soft tissue inset, and bony attachment. PMID:24691346

DeGeorge, Brent R; Rodeheaver, George T; Drake, David B

2014-06-01

230

The Effect of Lubricin on the Gliding Resistance of Mouse Intrasynovial Tendon  

PubMed Central

The purpose of this study was to investigate the role of lubricin on the gliding resistance of intrasynovial tendons by comparing lubricin knockout, heterozygous, and wild type mice. A total of thirty-six deep digital flexor (DDF) tendons in the third digits of each hind paw from eighteen adult mice were used, including six lubricin knockout mice (Prg4 –/–), six heterozygous mice (Prg4 +/–), and six wild type mice (Prg4 +/+). The tendon gliding resistance was measured using a custom-made device. Tendon structural changes were evaluated by scanning electron and light microscopy. The gliding resistance of intrasynovial tendons from lubricin knockout mice was significantly higher than the gliding resistance of either wild type or heterozygous mice. The surface of the lubricin knockout tendons appeared to be rougher, compared to the wild type and heterozygous tendons. Synovial hyperplasia was found in the lubricin knockout mice. Cartilage-like tissue was found in the tendon and pulley of the lubricin knockout mice. Our findings confirm the importance of lubricin in intrasynovial tendon lubrication. This knockout model may be useful in determining the effect of lubricin on tendon healing and the response to injury. PMID:24349551

Hayashi, Masanori; Zhao, Chunfeng; Thoreson, Andrew R.; Chikenji, Takako; Jay, Gregory D.; An, Kai-Nan; Amadio, Peter C.

2013-01-01

231

Tenogenic differentiation of stem cells for tendon repair-what is the current evidence?  

PubMed

Tendon/ligament injuries are very common in sports and other rigorous activities. Tendons regenerate and repair slowly and inefficiently in vivo after injury. The limited ability of tendon to self-repair and the general inefficiencies of current treatment regimes have hastened the motivation to develop tissue-engineering strategies for tissue repair. Of particular interest in recent years has been the use of adult mesenchymal stem cells (MSCs) to regenerate functional tendons and ligaments. Different sources of MSCs have been studied for their effects on tendon repair. However, ectopic bone and tumour formation has been reported in some special circumstances after transplantation of MSCs. The induction of MSCs to differentiate into tendon-forming cells in vitro prior to transplantation is a possible approach to avoid ectopic bone and tumour formation while promoting tendon repair. While there are reports about the factors that might promote tenogenic differentiation, the study of tenogenic differentiation is hampered by the lack of definitive biomarkers for tendons. This review aims to summarize the cell sources currently used for tendon repair as well as their advantages and limitations. Factors affecting tenogenic differentiation were summarized. Molecular markers currently used for assessing tenogenic differentiation or neotendon formation are summarized and their advantages and limitations are commented upon. Finally, further directions for promoting and assessing tenogenic differentiation of stem cells for tendon repair are discussed. PMID:21548133

Lui, P P Y; Rui, Y F; Ni, M; Chan, K M

2011-08-01

232

Treatment of peroneal nerve injuries with simultaneous tendon transfer and nerve exploration  

PubMed Central

Background Common peroneal nerve palsy leading to foot drop is difficult to manage and has historically been treated with extended bracing with expectant waiting for return of nerve function. Peroneal nerve exploration has traditionally been avoided except in cases of known traumatic or iatrogenic injury, with tendon transfers being performed in a delayed fashion after exhausting conservative treatment. We present a new strategy for management of foot drop with nerve exploration and concomitant tendon transfer. Method We retrospectively reviewed a series of 12 patients with peroneal nerve palsies that were treated with tendon transfer from 2005 to 2011. Of these patients, seven were treated with simultaneous peroneal nerve exploration and repair at the time of tendon transfer. Results Patients with both nerve repair and tendon transfer had superior functional results with active dorsiflexion in all patients, compared to dorsiflexion in 40% of patients treated with tendon transfers alone. Additionally, 57% of patients treated with nerve repair and tendon transfer were able to achieve enough function to return to running, compared to 20% in patients with tendon transfer alone. No patient had full return of native motor function resulting in excessive dorsiflexion strength. Conclusion The results of our limited case series for this rare condition indicate that simultaneous nerve repair and tendon transfer showed no detrimental results and may provide improved function over tendon transfer alone. PMID:25099247

2014-01-01

233

The adaptability of tendon to loading differs in men and women  

PubMed Central

The reason why women sustain more soft tissue injury than men during physical activity is unknown. Connective tissue properties and extracellular matrix adaptability in human tendon were investigated in models that addressed biochemical, physiological and biomechanical aspects of tendon connective tissue in response to mechanical loading. Habitual training resulted in a larger patellar tendon in men but not in women. Following an acute bout of exercise, men had an elevated tendon collagen synthesis rate and this effect was less pronounced or absent in women. Moreover, levels of circulating oestrogen affected the acute exercise-related increase in collagen synthesis. Finally, the mechanical strength of isolated tendon collagen fascicles in men surpassed that of women. Thus, compared to men, women have (i) an attenuated tendon hypertrophy response to habitual training; (ii) a lower tendon collagen synthesis rate following acute exercise; (iii) a rate of tendon collagen synthesis which is further attenuated with elevated estradiol levels; and (iv) a lower mechanical strength of their tendons. These data indicate that tendons in women have a lower rate of new connective tissue formation, respond less to mechanical loading, and have a lower mechanical strength, which may leave the tissue more susceptible to injury. PMID:17696904

Peter Magnusson, S; Hansen, Mette; Langberg, Henning; Miller, Ben; Haraldsson, Bjarki; Kjoeller Westh, Eva; Koskinen, Satu; Aagaard, Per; Kjær, Michael

2007-01-01

234

Avoidance of unfavourable results following primary flexor tendon surgery  

PubMed Central

This review describes the biological problems faced by those managing primary flexor tendon injuries and explains why these problems still thwart attempts to achieve normal, or near normal, function after this injury, despite a century of surgical effort. It considers the historical background of the early 20th century attempts to improve the results and analyses the clinical usefulness of more recent research into tendon core and circumferential suture modification, including the authors’ work in this field, and changes in post-operative mobilisation over the last 50 years. More recent manipulation of the sheath to improve results and the future possibility of manipulation of adhesions are discussed. It also discusses other factors, e.g., the patient, the experience of the surgeon, the use of therapists, the timing of repair, complex injuries, injuries in zones other than zone 2, which can have a bearing on the results and considers how these can be modified to avoid an unfavourable outcome. PMID:24501468

Elliot, D.; Giesen, T.

2013-01-01

235

[Effects of Gravity on Attachment of Tendon to Bone  

NASA Technical Reports Server (NTRS)

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

Johnson, Roger B.

1997-01-01

236

[Evaluation of surgical repair of distal biceps tendon ruptures].  

PubMed

PURPOSE OF THE STUDY To present the results of surgical repair of ruptures of the distal tendon of the biceps brachii muscle and thus show the adequacy of this treatment. MATERIAL Between 1987 and 2006, 19 patients had surgery for distal biceps tendon rupture. Only one side was affected in each patient. All patients were men between 28 and 69 years (average age, 47.5 years) at the time of injury (surgery). When the patients were evaluated at the end of 2007, 18 patients were included, because one died a year after surgery. METHODS The surgical repair always included a single-incision anatomical reattachment into the radial tuberosity. In 11 patients, a modified Mac Reynolds method with screw and washer fixation was used; in seven patients the insertion was fixed with Mitek anchors and, in one, it was sutured to the adjacent soft tissues. The average follow-up was 7 years (range, 1 to 20.5 years). The patients were evaluated for the cause of injury, their physical activity, age, dominance of the injured arm, surgical procedure and complications. RESULTS In 18 patients surgical repair was done early and, in one, at 16 days after injury. In all of them the tendon was detached from its site of insertion, but never torn. The intra-operative complications included, in one patient, bleeding owing to iatrogenic damage to a branch of the brachial artery, and difficult separation of the tendon due to its previous healed injury in another patient. Early post-operative complications included superficial skin necrosis in one patient and transient neurological deficit of the dorsal brand of the radial nerve and of the lateral cutaneous nerve of the forearm in two and one patient, respectively. The late complications were heterotropic ossification in three patients and screw migration in the one treated by the Mac Reynolds method. Excellent results were recorded in 11 patients (61 %), and good outcomes with a slight restriction of motion or muscle strength not limiting the patient's physical activities were in six (33.5 %) patients; only one patient (5.5 %) experienced pain on moderate exercise and had recurrent heterotropic ossification. Apart from this condition, there was no difference in the frequency of complications associated with the method used. DISCUSSION Only sparse information on distal biceps tendon ruptures has been available in the relevant Czech literature and, if so, only small groups with short follow-ups have been involved. Conservative treatment or the methods of non-anatomical reattachment have poor functional outcomes. Much better results are achieved by anatomical reattachment. Based on our experience with the Mac Reynolds technique, an anterior single-incision approach using fixation with Mitek anchors can be recommended. CONCLUSIONS Early surgical repair involving anatomical reattachment from the anterior singleincision approach with two Mitek anchors is recommended when a rupture of the distal tendon insertion of the biceps brachii is diagnosed. Key words: biceps radii muscle, biceps tendon injury, tendon fixation, bone screw and washer use. PMID:19268049

Behounek, J; Hrubina, M; Skoták, M; Krumpl, O; Zahálka, M; Dvorák, J; Fucík, M

2009-02-01

237

An improved force feedback control algorithm for active tendons.  

PubMed

An active tendon, consisting of a displacement actuator and a co-located force sensor, has been adopted by many studies to suppress the vibration of large space flexible structures. The damping, provided by the force feedback control algorithm in these studies, is small and can increase, especially for tendons with low axial stiffness. This study introduces an improved force feedback algorithm, which is based on the idea of velocity feedback. The algorithm provides a large damping ratio for space flexible structures and does not require a structure model. The effectiveness of the algorithm is demonstrated on a structure similar to JPL-MPI. The results show that large damping can be achieved for the vibration control of large space structures. PMID:23112660

Guo, Tieneng; Liu, Zhifeng; Cai, Ligang

2012-01-01

238

An Improved Force Feedback Control Algorithm for Active Tendons  

PubMed Central

An active tendon, consisting of a displacement actuator and a co-located force sensor, has been adopted by many studies to suppress the vibration of large space flexible structures. The damping, provided by the force feedback control algorithm in these studies, is small and can increase, especially for tendons with low axial stiffness. This study introduces an improved force feedback algorithm, which is based on the idea of velocity feedback. The algorithm provides a large damping ratio for space flexible structures and does not require a structure model. The effectiveness of the algorithm is demonstrated on a structure similar to JPL-MPI. The results show that large damping can be achieved for the vibration control of large space structures. PMID:23112660

Guo, Tieneng; Liu, Zhifeng; Cai, Ligang

2012-01-01

239

Tendon-derived stem/progenitor cell aging: defective self-renewal and altered fate.  

PubMed

Aging is a major risk factor for tendon injury and impaired tendon healing, but the basis for these relationships remains poorly understood. Here we show that rat tendon- derived stem ? progenitor cells (TSPCs) differ in both self-renewal and differentiation capability with age. The frequency of TSPCs in tendon tissues of aged animals is markedly reduced based on colony formation assays. Proliferation rate is decreased, cell cycle progression is delayed and cell fate patterns are also altered in aged TSPCs. In particular, expression of tendon lineage marker genes is reduced while adipocytic differentiation increased. Cited2, a multi-stimuli responsive transactivator involved in cell growth and senescence, is also downregulated in aged TSPCs while CD44, a matrix assembling and organizing protein implicated in tendon healing, is upregulated, suggesting that these genes participate in the control of TSPC function. PMID:20569237

Zhou, Zuping; Akinbiyi, Takintope; Xu, Lili; Ramcharan, Melissa; Leong, Daniel J; Ros, Stephen J; Colvin, Alexis C; Schaffler, Mitchell B; Majeska, Robert J; Flatow, Evan L; Sun, Hui B

2010-10-01

240

Tendon-Derived Stem/Progenitor Cell Aging: Defective Self-renewal and Altered Fate  

PubMed Central

Summary Aging is a major risk factor for tendon injury and impaired tendon healing, but the basis for these relationships remains poorly understood. Here we show that rat tendon-derived stem/progenitor cells (TSPCs) differ in both self-renewal and differentiation capability with age. The frequency of TSPCs in tendon tissues of aged animals is markedly reduced based on colony formation assays. Proliferation rate is decreased, cell cycle progression is delayed and cell fate patterns are also altered in aged TSPCs. In particular, expression of tendon lineage marker genes decreased while adipocytic differentiation increased. Cited2, a multi-stimuli responsive transactivator involved in cell growth and senescence, was also downregulated in aged TSPCs while CD44, a matrix assembling and organizing protein implicated in tendon healing, was upregulated, suggesting that these genes participate in the control of TSPC function. PMID:20569237

Zhou, Zuping; Akinbiyi, Takintope; Xu, Lili; Ramcharan, Melissa; Leong, Daniel J.; Ros, Stephen J.; Colvin, Alexis C.; Schaffler, Mitchell B.; Majeska, Robert J.; Flatow, Evan L.; Sun, Hui B.

2010-01-01

241

The effects of human amniotic membrane and periosteal autograft on tendon healing: experimental study in rabbits.  

PubMed

In this study, the effects of periosteal autograft and human amniotic membrane on tendon healing were compared. Forty-two New Zealand rabbits were divided into three groups. Flexor digitorum fibularis tendons were cut and repaired with a modified Kessler technique and circumferential sutures in all groups. Tendon repair alone was carried out in group 1, tendon repair and application of human amniotic membrane was done in group 2 and tendon repair and application of periosteal autograft was done in group 3. Biomechanical and histopathological examinations were done 2 and 6 weeks postoperatively. Biomechanical examination showed that group 3 was the strongest at weeks 2 and 6. Adhesion, inflammation and new bone formation showed no difference between groups at week 2. However, adhesion formation was found to be less in groups 2 and 3 than group 1 at week 6. The application of periosteal autograft might be useful in repair of tendon injuries. PMID:19687075

Ozbölük, S; Ozkan, Y; Oztürk, A; Gül, N; Ozdemir, R M; Yanik, K

2010-05-01

242

Gene expression markers of tendon fibroblasts in normal and diseased tissue compared to monolayer and three dimensional culture systems  

PubMed Central

Background There is a paucity of data regarding molecular markers that identify the phenotype of the tendon cell. This study aims to quantify gene expression markers that distinguish between tendon fibroblasts and other mesenchymal cells which may be used to investigate tenogenesis. Methods Expression levels for 12 genes representative of musculoskeletal tissues, including the proposed tendon progenitor marker scleraxis, relative to validated reference genes, were evaluated in matched samples of equine tendon (harvested from the superficial digital flexor tendon), cartilage and bone using quantitative PCR (qPCR). Expression levels of genes associated with tendon phenotype were then evaluated in healthy, including developmental, and diseased equine tendon tissue and in tendon fibroblasts maintained in both monolayer culture and in three dimensional (3D) collagen gels. Results Significantly increased expression of scleraxis was found in tendon compared with bone (P = 0.002) but not compared to cartilage. High levels of COL1A2 and scleraxis and low levels of tenascin-C were found to be most representative of adult tensional tendon phenotype. While, relative expression of scleraxis in developing mid-gestational tendon or in acute or chronically diseased tendon did not differ significantly from normal adult tendon, tenascin-C message was significantly upregulated in acutely injured equine tendon (P = 0.001). Relative scleraxis gene expression levels in tendon cell monolayer and 3D cultures were significantly lower than in normal adult tendon (P = 0.002, P = 0.02 respectively). Conclusion The findings of this study indicate that high expression of both COL1A2 and scleraxis, and low expression of tenascin-C is representative of a tensional tendon phenotype. The in vitro culture methods used in these experiments however, may not recapitulate the phenotype of normal tensional tendon fibroblasts in tissues as evidenced by gene expression. PMID:19245707

Taylor, Sarah E; Vaughan-Thomas, Anne; Clements, Dylan N; Pinchbeck, Gina; Macrory, Lisa C; Smith, Roger KW; Clegg, Peter D

2009-01-01

243

Corrosion of steel tendons used in prestressed concrete pressure vessels  

Microsoft Academic Search

The corrosion behavior of a high-strength steel (Specifications for Uncoated Seven-Wire-Stress-Relieved Strand for Prestressed Concrete (ASTM A 416-74, Grade 270)), typical of those used as tensioning tendons in prestressed concrete pressure vessels was measured in several corrosive environments. The protection obtained by coating the steel with two commercial petroleum-base greases or with Portland cement grout was evaluated. The few reported

J. C. Griess; D. J. Naus

1980-01-01

244

Corrosion of steel tendons used in prestressed concrete pressure vessels  

Microsoft Academic Search

The purpose of this investigation was to determine the corrosion behavior of a high strength steel (ASTM A416-74 grade 270), typical of those used as tensioning tendons in prestressed concrete pressure vessels, in several corrosive environments and to demonstrate the protection afforded by coating the steel with either of two commercial petroleum-base greases or Portland Cement grout. In addition, the

J. C. Griess; D. J. Naus

2009-01-01

245

An Evaluation of Suture Materials Used in Tendon Surgery  

Microsoft Academic Search

The following suture materials have been evaluated for their suitability for use in flexor tendon repairs: 4\\/0 gauge monofilament and multifilament stainless steel, mono-filament nylon, monofilament polypropylene, monofilament polybutestor, braided polyester, braided polyglycolic acid and a monofilament polyglyconate. These were investigated for their tensile strength (both knotted and unknotted), their extension to failure and knot-holding properties. Stainless steel and monofilament

I. A. TRAIL; E. S. POWELL; J. NOBLE

1989-01-01

246

Freeze-thaw cycles enhance decellularization of large tendons.  

PubMed

The use of decellularized tendon tissue as a scaffold for tendon tissue engineering provides great opportunities for future clinical and current research applications. The aim of this study was to assess the effect of repetitive freeze-thaw cycles and two different detergents, t-octyl-phenoxypolyethoxyethanol (Triton X-100) and sodium dodecyl sulfate (SDS), on decellularization effectiveness and cytocompatibility in large tendons. Freshly collected equine superficial and deep digital flexor tendons were subjected to decellularization according to four different protocols (1 and 2: freeze-thaw cycles combined with either Triton X-100 or SDS; 3 and 4: Triton X-100 or SDS). Decellularization effectiveness was assessed based on the reduction of vital cell counts, histologically visible nuclei, and DNA content. Transmission electron microscopy was performed to evaluate cellular and extracellular matrix integrity. Further, cytocompatibility of scaffolds that had been decellularized according to the protocols including freeze-thaw cycles (protocols 1 and 2) was assessed by seeding the scaffolds with superparamagnetic iron oxide labeled mesenchymal stromal cells and monitoring the cells histologically and by magnetic resonance imaging for two weeks. Decellularization was significantly more effective when using the protocols including freeze-thaw cycles, leaving only roughly 1% residual nuclei and 20% residual DNA, whereas samples that had not undergone additional freeze-thaw cycles contained roughly 20% residual nuclei and 40% residual DNA. No morphological extracellular matrix alterations due to decellularization could be observed. Scaffolds prepared by both protocols including freeze-thaw cycles were cytocompatible, but the cell distribution into the scaffold tended to be better in scaffolds that had been decellularized using freeze-thaw cycles combined with Triton X-100 instead of SDS. PMID:23879725

Burk, Janina; Erbe, Ina; Berner, Dagmar; Kacza, Johannes; Kasper, Cornelia; Pfeiffer, Bastian; Winter, Karsten; Brehm, Walter

2014-04-01

247

Freeze-Thaw Cycles Enhance Decellularization of Large Tendons  

PubMed Central

The use of decellularized tendon tissue as a scaffold for tendon tissue engineering provides great opportunities for future clinical and current research applications. The aim of this study was to assess the effect of repetitive freeze-thaw cycles and two different detergents, t-octyl-phenoxypolyethoxyethanol (Triton X-100) and sodium dodecyl sulfate (SDS), on decellularization effectiveness and cytocompatibility in large tendons. Freshly collected equine superficial and deep digital flexor tendons were subjected to decellularization according to four different protocols (1 and 2: freeze-thaw cycles combined with either Triton X-100 or SDS; 3 and 4: Triton X-100 or SDS). Decellularization effectiveness was assessed based on the reduction of vital cell counts, histologically visible nuclei, and DNA content. Transmission electron microscopy was performed to evaluate cellular and extracellular matrix integrity. Further, cytocompatibility of scaffolds that had been decellularized according to the protocols including freeze-thaw cycles (protocols 1 and 2) was assessed by seeding the scaffolds with superparamagnetic iron oxide labeled mesenchymal stromal cells and monitoring the cells histologically and by magnetic resonance imaging for two weeks. Decellularization was significantly more effective when using the protocols including freeze-thaw cycles, leaving only roughly 1% residual nuclei and 20% residual DNA, whereas samples that had not undergone additional freeze-thaw cycles contained roughly 20% residual nuclei and 40% residual DNA. No morphological extracellular matrix alterations due to decellularization could be observed. Scaffolds prepared by both protocols including freeze-thaw cycles were cytocompatible, but the cell distribution into the scaffold tended to be better in scaffolds that had been decellularized using freeze-thaw cycles combined with Triton X-100 instead of SDS. PMID:23879725

Erbe, Ina; Berner, Dagmar; Kacza, Johannes; Kasper, Cornelia; Pfeiffer, Bastian; Winter, Karsten; Brehm, Walter

2014-01-01

248

Tendon-to-Tuberosity Repair: Lateral Footprint Fixation  

Microsoft Academic Search

Presently, there is no one technique for tendon-to-tuberosity repair that has been proven superior in any prospective, randomized\\u000a clinical study.1,2 At this point, the orthopedic surgeon must decide on a surgical technique based on another surgeon’s personal preference\\u000a and on a small number of relatively short-term clinical studies. As this textbook aims to capture not only the variations\\u000a in technique

Gary M. Gartsman

249

Mineralized fibroma of the tendon sheath presenting as a bursitis  

Microsoft Academic Search

We report on the clinical, imaging—including ultrasound, computed tomography, and magnetic resonance imaging—and histological\\u000a features of a fibroma of the tendon sheath with mineralized chondroid and osseous metaplasia, presenting as a semimembranosus\\u000a bursitis. The anatomical characteristics of the semimembranosus bursa are demonstrated by dissection in a cadaveric specimen\\u000a and correlated with the imaging findings in our patient.

Thomas Le Corroller; Corinne Bouvier-Labit; Abderrahmane Sbihi; Pierre Champsaur

2008-01-01

250

Preparation of Rat Tail Tendons for Biomechanical and Mechanobiological Studies  

PubMed Central

Rat tail tendons (RTTs) are a common biological model used in experimental in vitro studies in the fields of tendon physiology and tendinopathy. Working with those tissues is challenging because they are very fragile, and until now there was no rigorously detailed protocol for their isolation. Faced with these challenges, we have developed methods and instruments to facilitate manipulation of RTTs and control tissue viability, sterility and integrity. This article describes the experimental procedures used to prepare RTTs for biomechanical and mechanobiological studies. Our work is divided into four main steps: extraction, cross-sectional area measurement, rinsing and loading into the bioreactor chamber. At each step, all procedures, materials and manipulations are presented in detail so that they can be easily reproduced. Moreover, the specific instruments developed are presented: a manipulation plate used to segregate RTTs, an optic micrometer to position the tissue during the cross-sectional area measurement and an anchoring system to attach the RTTs onto a bioreactor. Finally, we describe the results obtained after multiple tests to validate our methods. The viability, sterility and integrity evaluations demonstrate that our procedures are sufficiently rigorous for manipulations of fragile tissues such as rat tail tendons. PMID:20729800

Bruneau, Amélie; Champagne, Nadia; Cousineau-Pelletier, Paule; Parent, Gabriel; Langelier, Eve

2010-01-01

251

Influence of tendon slack on electromechanical delay in the human medial gastrocnemius in vivo  

Microsoft Academic Search

Abstract The purpose ,of this study was to clarify the influence of muscle-tendon, complex stretch on electromechanical delay (EMD) in terms,of the extent of tendon,slack in the human,medial ,gastrocnemius ,(MG). EMD and MG tendon ,length were measured ,at each of five ankle joint angles (-30•, -20, -10, 0 and 5: positive values for dorsiflexion) using percutaneous electrical stimulation and ultrasonography,

Tetsuro Muraoka; Tadashi Muramatsu; Tetsuo Fukunaga; Hiroaki Kanehisa

2003-01-01

252

The effect of tendon on muscle force in dynamic isometric contractions: A simulation study  

Microsoft Academic Search

Recently, Baratta and Solomonow J. Biomechanics24, 109–116 (1991) studied the effect of tendon on muscle-tendon complex behavior in cat tibialis anterior (TA) muscle. This was done by determining the relation between neural stimulation and muscle force in a dynamic isometric experiment, both before and after the removal of the distal tendon. From their results, Baratta and Solomonow concluded that in

Arthur J. van Soest; Peter A. Huijing; Moshe Solomonow

1995-01-01

253

Collagen fibre implant for tendon and ligament biological augmentation. In vivo study in an ovine model  

E-print Network

the right balance between strength and resorption rate of collagen fibres. Keywords Tissue engineering #2; Collagen fibre #2; Augmentation #2; Collagen crosslinking #2; Tendon repair Introduction Tendon and ligament injuries often result in large tissue gaps... Orthop Surg 6:169–175 29. Spindler KP, Kuhn JE, Freedman KB, Matthews CE, Dittus RS, Harrell FE Jr (2004) Anterior cruciate ligament reconstruction autograft choice: bone-tendon-bone versus hamstring: does it really matter? A systematic review. Am J...

Enea, D; Gwynne, J; Kew, S; Arumugam, M; Shepherd, J; Brooks, R; Ghose, S; Best, Serena Michelle; Cameron, Ruth Elizabeth; Rushton, N

2012-06-20

254

Effects of various decellularization methods on histological and biomechanical properties of rabbit tendons  

PubMed Central

The aim of the present study was to investigate the effects of various decellularization methods on the histological and biomechanical properties of rabbit tendons. In total, six chemical reagents, including 1% t-octyl-phenoxypolyethoxyethanol (Triton-X 100), 0.5% sodium dodecyl sulfate (SDS), 1% tri-n-butyl phosphate (TnBP), 1% Triton-X 100 + 0.5% SDS, 1% TnBP + 0.5% SDS and 1% TnBP + 1% Triton-X 100, were used on rabbit semitendinosus muscles and flexor digitorum tendons for 24 h to remove cells. Hematoxylin and eosin staining was applied for histological observation, while tension testing was used for biomechanical studies. The effects of the various decellularization methods on the histological structure and biomechanical properties of rabbit tendons were evaluated. A group of fresh tendons treated with phosphate-buffered saline served as controls. The various decellularization methods resulted in different effects on the tendons. All the treatment groups exhibited a decrease in tendon biomechanical properties, but no statistically significant differences were observed among the experimental groups. The extensibility of the 1% TnBP-treated group was found to be greater than that of the other groups; however, the difference was not statistically significant. Histologically, the 1% TnBP + 0.5% SDS treatment was shown to have the least impact on the rabbit tendon structure, with good decellularization and no clear cellular remnants observed. The 1% Triton-X 100 + 0.5% SDS treatment had a pronounced effect on the tendon collagen structure and a number of collagen ruptures were observed. Overall, 1% TnBP + 0.5% SDS was found to be the most effective compared with the other treatments, as this treatment preserved the tendon collagen structure while completely removing the cells. Tendons treated with 1% TnBP + 0.5% SDS were histologically similar to normal tendon tissue and biomechanically similar to the tendons in the control group. PMID:25009631

XING, SHUXING; LIU, CONG; XU, BING; CHEN, JIANCHANG; YIN, DONGFENG; ZHANG, CHUNHAO

2014-01-01

255

Acute Simultaneous Ruptures of the Anterior Cruciate Ligament and Patellar Tendon  

PubMed Central

Acute simultaneous rupture of the anterior cruciate ligament (ACL) and patellar tendon is a rare injury. We present a case report of a 32-year-old male patient with ruptured ACL and ipsilateral patellar tendon rupture sustained while playing baseball. Surgery was performed on the patellar tendon and the ACL simultaneously. The clinical and radiological outcomes of the treatment were successful. We present this case with a review of the literatures. PMID:24639949

Lee, Gwang Chul; Park, Sung-Hae

2014-01-01

256

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

Microsoft Academic Search

Background: Although a rare event, the prevalence of major tendon rupture has increased in recent decades. Identification of risk factors is important for prevention purposes.Hypothesis: Race is a risk factor for major tendon ruptures.Study Design: Cohort study (prevalence); Level of evidence, 2.Methods: All patients admitted for surgical management of a rupture of a major tendon at Womack Army Medical Center,

Daniel W. White; Joseph C. Wenke; Dan S. Mosely; Sally B. Mountcastle; Carl J. Basamania

2007-01-01

257

Peroneus longus tendon lengthening as an adjuvant measure in cavus foot surgery.  

PubMed

Lengthening of the peroneus longus tendon is very important when performing cavus foot surgery. This tendon directly affects all three components (varus heel, increased arch height, and forefoot adduction) of the idiopathic cavus foot which can be accounted for by increased strength and activity of the peroneus muscle. The deforming force is removed or weakened according to the degree, duration and rigidity of the cavus foot by lengthening or transferring the tendon. PMID:1025187

Smith, S D; Weil, L S

1976-01-01

258

Arthroscopic repair of the subscapularis tendon: indications, limits and technical features  

PubMed Central

Summary The rationale to anatomically repair this tendon is to restore the functional biomechanics of the shoulder. Clinical and imaging assessment are required before undertaking arthroscopy. In this way, associated pathologies of the biceps and labrum may be successfully addressed. The arthroscopic repair of the tendon implies to use suture anchors and reinsert the tendon itself over the footprint. Results after arthroscopy are comparable to those observed after open procedures. PMID:24367783

Osti, Leonardo; Soldati, Francesco; Del Buono, Angelo; Buda, Matteo

2013-01-01

259

Arthroscopic repair of the subscapularis tendon: indications, limits and technical features.  

PubMed

The rationale to anatomically repair this tendon is to restore the functional biomechanics of the shoulder. Clinical and imaging assessment are required before undertaking arthroscopy. In this way, associated pathologies of the biceps and labrum may be successfully addressed. The arthroscopic repair of the tendon implies to use suture anchors and reinsert the tendon itself over the footprint. Results after arthroscopy are comparable to those observed after open procedures. PMID:24367783

Osti, Leonardo; Soldati, Francesco; Buono, Angelo Del; Buda, Matteo

2013-01-01

260

Slack length of gastrocnemius medialis and Achilles tendon occurs at different ankle angles.  

PubMed

Although muscle-tendon slack length is a crucial parameter used in muscle models, this is one of the most difficult measures to estimate in vivo. The aim of this study was to determine the onset of the rise in tension (i.e., slack length) during passive stretching in both Achilles tendon and gastrocnemius medialis. Muscle and tendon shear elastic modulus was measured by elastography (supersonic shear imaging) during passive plantarflexion (0° and 90° of knee angle, 0° representing knee fully extended, in a random order) in 9 participants. The within-session repeatability of the determined slack length was good at 90° of knee flexion (SEM=3.3° and 2.2° for Achilles tendon and gastrocnemius medialis, respectively) and very good at 0° of knee flexion (SEM=1.9° and 1.9° for Achilles tendon and gastrocnemius medialis, respectively). The slack length of gastrocnemius medialis was obtained at a significantly lower plantarflexed angle than for Achilles tendon at both 0° (P<0.0001; mean difference=19.4±3.8°) and 90° of knee flexion (P<0.0001; mean difference=25.5±7.6°). In conclusion, this study showed that the joint angle at which the tendon falls slack can be experimentally determined using supersonic shear imaging. The slack length of gastrocnemius medialis and Achilles tendon occurred at different joint angles. Although reporting this result is crucial to a better understanding of muscle-tendon interactions, further experimental investigations are required to explain this result. PMID:23953502

Hug, François; Lacourpaille, Lilian; Maïsetti, Olivier; Nordez, Antoine

2013-09-27

261

Influence of tendon slack on electromechanical delay in the human medial gastrocnemius in vivo.  

PubMed

The purpose of this study was to clarify the influence of muscle-tendon complex stretch on electromechanical delay (EMD) in terms of the extent of tendon slack in the human medial gastrocnemius (MG). EMD and MG tendon length were measured at each of five ankle joint angles (-30, -20, -10, 0, and 5 degrees : positive values for dorsiflexion) using percutaneous electrical stimulation and ultrasonography, respectively. The extent of MG tendon slack was calculated as MG tendon length shortening, standardized with MG tendon slack length obtained at the joint angle (-16 degrees +/- 5 degrees ) where the passive ankle joint torque was zero. EMD at -30 degrees (19.2 +/-2.2 ms) and -20 degrees (17.2 +/- 1.3 ms) was significantly greater than that at -10 degrees (16.0 +/-2.3 ms), 0 degrees (15.0 +/-1.4 ms), and 5 degrees (14.8 +/-1.4 ms), and at 0 and 5 degrees, respectively. The relative EMD, normalized with the maximal EMD for each subject, decreased dependent on the extent of decrease in MG tendon slack. There were no significant differences in EMD among the joint angles (-10, 0, and 5 degrees ) where MG tendon slack was taken up. These results suggest that the extent of tendon slack is an important factor for determining EMD. PMID:14527969

Muraoka, Tetsuro; Muramatsu, Tadashi; Fukunaga, Tetsuo; Kanehisa, Hiroaki

2004-02-01

262

The effect of enrofloxacin on cell proliferation and proteoglycans in horse tendon cells.  

PubMed

Fluoroquinolone antibiotics have been used widely in humans and domestic animals, including horses, because of their broad-spectrum bactericidal activity, and relative safety. The use of fluoroquinolones, however, is not without risk. Tendonitis and spontaneous tendon rupture have been reported in people during or following therapy with fluoroquinolones. We have studied the effects of enrofloxacin, a fluoroquinolone antibiotic used commonly in domestic animals, on tendon cell cultures established from equine superficial digital flexor tendons. Effects on cell proliferation and morphology were studied using cell counting and scanning electron microscopy. Monosaccharide content and composition was determined by gas chromatography-mass spectrometry analysis. Western and Northern blot analyses were utilized to evaluate the synthesis and expression of two proteoglycans, biglycan and decorin. Our data demonstrate that enrofloxacin inhibits cell proliferation, induces morphological changes, decreases total monosacharide content and alters small proteoglycan synthesis at the glycosylation level in equine tendon cell cultures. These effects are more pronounced in juvenile tendon cells than in adult equine tendon cells. We hypothesize that morphological changes and inhibition of cell proliferation are a result of impaired production of biglycan and decorin, proteoglycans involved in fibrillogenesis of collagen, the most important structural component of the tendon of enrofloxacin-treated tendon cells. Our findings suggest that fluoroquinolones should be used with caution in horses, especially in foals. PMID:15119847

Yoon, J H; Brooks, R L; Khan, A; Pan, H; Bryan, J; Zhang, J; Budsberg, S C; Mueller, P O E; Halper, J

2004-02-01

263

Tendon proper- and peritenon-derived progenitor cells have unique tenogenic properties  

PubMed Central

Introduction Multipotent progenitor populations exist within the tendon proper and peritenon of the Achilles tendon. Progenitor populations derived from the tendon proper and peritenon are enriched with distinct cell types that are distinguished by expression of markers of tendon and vascular or pericyte origins, respectively. The objective of this study was to discern the unique tenogenic properties of tendon proper- and peritenon-derived progenitors within an in vitro model. We hypothesized that progenitors from each region contribute differently to tendon formation; thus, when incorporated into a regenerative model, progenitors from each region will respond uniquely. Moreover, we hypothesized that cell populations like progenitors were capable of stimulating tenogenic differentiation, so we generated conditioned media from these cell types to analyze their stimulatory potentials. Methods Isolated progenitors were seeded within fibrinogen/thrombin gel-based constructs with or without supplementation with recombinant growth/differentiation factor-5 (GDF5). Early and late in culture, gene expression of differentiation markers and matrix assembly genes was analyzed. Tendon construct ultrastructure was also compared after 45 days. Moreover, conditioned media from tendon proper-derived progenitors, peritenon-derived progenitors, or tenocytes was applied to each of the three cell types to determine paracrine stimulatory effects of the factors secreted from each of the respective cell types. Results The cell orientation, extracellular domain and fibril organization of constructs were comparable to embryonic tendon. The tendon proper-derived progenitors produced a more tendon-like construct than the peritenon-derived progenitors. Seeded tendon proper-derived progenitors expressed greater levels of tenogenic markers and matrix assembly genes, relative to peritenon-derived progenitors. However, GDF5 supplementation improved expression of matrix assembly genes in peritenon progenitors and structurally led to increased mean fibril diameters. It also was found that peritenon-derived progenitors secrete factor(s) stimulatory to tenocytes and tendon proper progenitors. Conclusions Data demonstrate that, relative to peritenon-derived progenitors, tendon proper progenitors have greater potential for forming functional tendon-like tissue. Furthermore, factors secreted by peritenon-derived progenitors suggest a trophic role for this cell type as well. Thus, these findings highlight the synergistic potential of including these progenitor populations in restorative tendon engineering strategies. PMID:25005797

2014-01-01

264

Scleraxis Expression Is Coordinately Regulated in a Murine Model of Patellar Tendon Injury  

PubMed Central

This study investigated the expression of scleraxis in a murine model of patellar tendon injury in which the central third of the patellar tendon was unilaterally injured. The presence of tendon pathology was assessed using dual photon microscopy, conventional histology and micro CT. Tendon pathology was also quantified noninvasively over a 12-week period using high-frequency ultrasound and laser Doppler flowmetry. Gene expression (Scx, Tnmd, and Col1a1) was determined at defined end-points (1, 4, 8, and 12 weeks) using qPCR on RNA from individual patellar tendons on injured and uninjured sides. There was significant development of tendon pathology as gauged by ultrasound and laser Doppler over 12 weeks. Injured tendons demonstrated significant histological and microCT evidence of pathological change, and disorganized collagen with reduced density. The expression of Scx and Col1a1 was unchanged at 1 week, significantly upregulated at 4 and 8 weeks, and had returned to baseline by 12 weeks. Tnmd expression was unchanged at 1 week, and significantly increased at 4, 8, and 12 weeks. Patellar tendon injury was associated with marked increases in the expression of Scx, Tnmd, and Col1a1. Our data suggest new roles for Scleraxis in coordinating the response to injury in the pathogenesis of tendon disorders. PMID:20740671

Scott, Alexander; Sampaio, Arthur; Abraham, Thomas; Duronio, Chris; Underhill, Tully M.

2014-01-01

265

Early Active Motion versus Immobilization after Tendon Transfer for Foot Drop Deformity: A Randomized Clinical Trial  

Microsoft Academic Search

Background  Immobilization after tendon transfers has been the conventional postoperative management. Several recent studies suggest early\\u000a mobilization does not increase tendon pullout.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  To confirm those studies we determined whether when compared with immobilization early active mobilization after a tendon\\u000a transfer for foot-drop correction would (1) have a similar low rate of tendon insertion pullout, (2) reduce rehabilitation\\u000a time, and (3) result

Santosh Rath; Ton A. R. Schreuders; Henk J. Stam; Steven E. R. Hovius; Ruud W. Selles

2010-01-01

266

Study of optical properties and proteoglycan content of tendons by polarization sensitive optical coherence tomography  

NASA Astrophysics Data System (ADS)

The highly orientated collagen fibers in tendons play a critical role for transferring tensile stress, and they demonstrate birefringent optical properties. However, the influence that proteoglycans (PGs) have on the optical properties of tendons is yet to be fully elucidated. PGs are the essential components of the tendon extracellular matrix; the changes in their quantities and compositions have been associated with tendinopathies. In this study, polarization sensitive optical coherence tomography (PS-OCT) has been used to reveal the relationship between PG content/location and birefringence properties of tendons. Fresh chicken tendons were imaged at regular intervals by PS-OCT and polarization light microscopy during the extraction of PGs, using guanidine hydrochloride (GuHCl). Complementary time-lapsed images taken from the two modalities mutually demonstrated that the extraction of PGs disturbed the local organization of collagen bundles. This corresponded with a decrease in birefringence and associated banding pattern observed by PS-OCT. Furthermore, this study revealed there was a higher concentration of PGs in the outer sheath region than in the fascicles, and therefore the change in birefringence was reduced when extraction was performed on unsheathed tendons. The results provide new insights of tendon structure and the role of PGs on the structural stability of tendons, which also demonstrates the great potential for using PS-OCT as a diagnostic tool to examine tendon pathology.

Yang, Ying; Rupani, Asha; Bagnaninchi, Pierre; Wimpenny, Ian; Weightman, Alan

2012-08-01

267

Study of optical properties and proteoglycan content of tendons by polarization sensitive optical coherence tomography.  

PubMed

The highly orientated collagen fibers in tendons play a critical role for transferring tensile stress, and they demonstrate birefringent optical properties. However, the influence that proteoglycans (PGs) have on the optical properties of tendons is yet to be fully elucidated. PGs are the essential components of the tendon extracellular matrix; the changes in their quantities and compositions have been associated with tendinopathies. In this study, polarization sensitive optical coherence tomography (PS-OCT) has been used to reveal the relationship between PG content/location and birefringence properties of tendons. Fresh chicken tendons were imaged at regular intervals by PS-OCT and polarization light microscopy during the extraction of PGs, using guanidine hydrochloride (GuHCl). Complementary time-lapsed images taken from the two modalities mutually demonstrated that the extraction of PGs disturbed the local organization of collagen bundles. This corresponded with a decrease in birefringence and associated banding pattern observed by PS-OCT. Furthermore, this study revealed there was a higher concentration of PGs in the outer sheath region than in the fascicles, and therefore the change in birefringence was reduced when extraction was performed on unsheathed tendons. The results provide new insights of tendon structure and the role of PGs on the structural stability of tendons, which also demonstrates the great potential for using PS-OCT as a diagnostic tool to examine tendon pathology. PMID:23224178

Yang, Ying; Rupani, Asha; Bagnaninchi, Pierre; Wimpenny, Ian; Weightman, Alan

2012-08-01

268

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

PubMed

Tendons are often injured and heal poorly. Whether this is caused by a slow tissue turnover is unknown, since existing data provide diverging estimates of tendon protein half-life that range from 2 mo to 200 yr. With the purpose of determining life-long turnover of human tendon tissue, we used the (14)C bomb-pulse method. This method takes advantage of the dramatic increase in atmospheric levels of (14)C, produced by nuclear bomb tests in 1955-1963, which is reflected in all living organisms. Levels of (14)C were measured in 28 forensic samples of Achilles tendon core and 4 skeletal muscle samples (donor birth years 1945-1983) with accelerator mass spectrometry (AMS) and compared to known atmospheric levels to estimate tissue turnover. We found that Achilles tendon tissue retained levels of (14)C corresponding to atmospheric levels several decades before tissue sampling, demonstrating a very limited tissue turnover. The tendon concentrations of (14)C approximately reflected the atmospheric levels present during the first 17 yr of life, indicating that the tendon core is formed during height growth and is essentially not renewed thereafter. In contrast, (14)C levels in muscle indicated continuous turnover. Our observation provides a fundamental premise for understanding tendon function and pathology, and likely explains the poor regenerative capacity of tendon tissue. PMID:23401563

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

2013-05-01

269

Effect of bone morphogenetic protein 2 on tendon-to-bone healing in a canine flexor tendon model.  

PubMed

Tendon-to-bone healing is typically poor, with a high rate of repair-site rupture. Bone loss after tendon-to-bone repair may contribute to poor outcomes. Therefore, we hypothesized that the local application of the osteogenic growth factor bone morphogenetic protein 2 (BMP-2) would promote bone formation, leading to improved repair-site mechanical properties. Intrasynovial canine flexor tendons were injured in Zone 1 and repaired into bone tunnels in the distal phalanx. BMP-2 was delivered to the repair site using either a calcium phosphate matrix (CPM) or a collagen sponge (COL) carrier. Each animal also received carrier alone in an adjacent repair to serve as an internal control. Repairs were evaluated at 21 days using biomechanical, radiographic, and histologic assays. Although an increase in osteoid formation was noted histologically, no significant increases in bone mineral density occurred. When excluding functional failures (i.e., ruptured and gapped repairs), mechanical properties were not different when comparing BMP-2/CPM groups with carrier controls. A significantly higher percentage of BMP-2 treated specimens had a maximum force <20 N compared to carrier controls. While tendon-to-bone healing can be enhanced by addressing the bone loss that typically occurs after surgical repair, the delivery of BMP-2 using the concentrations and methods of the current study did not improve mechanical properties over carrier alone. The anticipated anabolic effect of BMP-2 was insufficient in the short time frame of this study to counter the post-repair loss of bone. PMID:22618762

Thomopoulos, Stavros; Kim, H Mike; Silva, Matthew J; Ntouvali, Eleni; Manning, Cionne N; Potter, Ryan; Seeherman, Howard; Gelberman, Richard H

2012-11-01

270

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

PubMed

A retrospective study of patients who underwent gastrocnemius recession, double calcaneal osteotomy (Evans osteotomy and percutaneous calcaneal displacement osteotomy), and medial column fusion for the treatment of posterior tibial tendon dysfunction was conducted. The senior author performed the procedures between November 2002 and January 2009 on 34 patients who displayed at least Johnson and Strom stage II deformity and had undergone 12 months of failed conservative treatment. The coauthors evaluated the patients' radiographs before and after the operation. At a mean of 14 (range 3 to 44) months after surgery, radiographic measurements demonstrated statistically significant changes in the structural alignment of the feet. Based on our experience with these patients, we believe that a double calcaneal osteotomy combined with a gastrocnemius recession and stabilization of the medial column for the treatment of posterior tibial tendon dysfunction provides satisfactory correction, stability, and realignment of the foot. Furthermore, we feel that the use of flexor digitorum longus transfer, as well as triple arthrodesis, can be avoided without compromising the outcome when surgically treating posterior tibial tendon dysfunction. PMID:21397524

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

2011-01-01

271

Flexor tendon healing within the tendon sheath using bioabsorbable poly-L/D-lactide 96/4 suture. A histological in vivo study with rabbits.  

PubMed

The bioabsorbable poly-L/D-lactide (PLDLA) 96/4 suture has good biomechanical and knot properties, and sufficient tensile strength half-life for flexor tendon repair. In the present study, the biocompatibility of PLDLA suture was compared with that of coated braided polyester suture in the rabbit flexor digitorum profundus tendon repaired within the tendon sheath. Postoperative unrestricted active mobilization was allowed. The tendons were studied histologically after 1-, 3-, 6-, 12-, 26-, and 52-week follow-ups. No differences were found in the biocompatibility between the suture materials, with only scattered multinuclear giant cells near the sutures in both groups from 6 weeks onwards. At 52 weeks, most of the PLDLA material was absorbed and the histological structure of the tendon appeared normal, whereas in the polyester repairs the suture knots filled the repair site, causing bulking of the tendon surface, and the collagen alignment appeared disoriented. The results suggest that the PLDLA 96/4 is a suitable suture material for flexor tendon repair. PMID:24477875

Viinikainen, Anna; Göransson, Harry; Taskinen, Hanna-Stina; Röyttä, Matias; Kellomäki, Minna; Törmälä, Pertti; Rokkanen, Pentti

2014-05-01

272

[Isokinetic assessment with two years follow-up of anterior cruciate ligament reconstruction with patellar tendon or hamstring tendons].  

PubMed

This retrospective multicentric study was designed to assess the outcome of quadriceps and hamstrings muscles two years after Anterior Cruciate Ligament (ACL) reconstruction and compare muscles recovery depending on the type of graft and individual variables like age, gender, level of sport, but also in terms of discomfort, pain and functional score. The results focused on the subjective and objective IKDC scores, SF36, the existence or not of subjective disorders and their location. The review included isokinetic muscle tests concentric and eccentric extensors/flexors but also internal rotators/external rotators with analysis of mean work and mean power. One hundred and twenty-seven patients were included with an average age 29 years (+/-10). They all had an ACL reconstruction with patellar tendon or hamstring tendon with single or double bundles. In the serie, the average muscles deficit at two years was 10% for the flexors and extensors but with a significant dispersion. Significant differences were not noted in the mean values of all parameters in term of sex or age (over 30 years or not), neither the type of sport, nor of clinical assessment (Class A and B of objective IKDC score), nor the existence of anterior knee pain. There was a relationship between the level of extensor or flexor recovery and the quality of functional results with minimal muscle deficits close to 5% if the IKDC score was over 90 and deficits falling to 15% in the group with IKDC score less than 90. The type of reconstruction (patellar tendon versus hamstrings) had an influence on the muscle deficit. For extensors, the recovery was the same in the two groups, more than 90% at two years and the distribution of these two populations by level of deficit was quite the same. For flexors, residual deficits were significantly higher in the hamstrings group on the three studied parameters whatever the speed and the type of contraction (concentric or eccentric) with an average deficit of 14 to 18%, while, in the patellar tendon group, there was a dominance over the opposite side of 2 to 3% in concentric contraction. The hamstrings deficit appears to be "harvest dependent". For internal rotators, a significantly higher deficit is observed in eccentric contraction for the hamstrings group. The residual hamstrings deficits were related to the number of tendons harvested: -7% when there was no harvest, 7% with one tendon harvested and 17% with two tendons harvested. The relationship between the level of recovery of the quadriceps muscle and hamstrings at two years and the quality of functional results incite, regarding the significantly higher deficit of flexors in ACL reconstructions with hamstrings, to change the rehabilitation programs and especially on early rehabilitation of hamstrings in eccentric mode in the early weeks postoperative considering the harvest site as an equivalent of muscle tear. PMID:19046696

Condouret, J; Cohn, J; Ferret, J-M; Lemonsu, A; Vasconcelos, W; Dejour, D; Potel, J-F

2008-12-01

273

An approach to determine long-term behavior of concrete members prestressed with FRP tendons  

Microsoft Academic Search

The combined effects of creep and shrinkage of concrete and relaxation of prestressing tendons cause gradual changes in the stresses in both concrete and prestressing tendons. A simple method is presented to calculate the long-term prestress loss and the long-term change in concrete stresses in continuous prestressed concrete members with either carbon fiber reinforced polymer (CFRP) or aramid fiber reinforced

Samer A. Youakim; Vistasp M. Karbhari

2007-01-01

274

Investigation of 2D and 3D electrospun scaffolds intended for tendon repair.  

PubMed

Two-dimensional (2D) electrospun fibre mats have been investigated as fibrous sheets intended as biomaterials scaffolds for tissue repair. It is recognised that tissues are three-dimensional (3D) structures and that optimisation of the fabrication process should include both 2D and 3D scaffolds. Understanding the relative merits of the architecture of 2D and 3D scaffolds for tendon repair is required. This study investigated three different electrospun scaffolds based on poly(?-caprolactone) fibres intended for repair of injured tendons, referred to as; 2D random sheet, 2D aligned sheet and 3D bundles. 2D aligned fibres and 3D bundles mimicked the parallel arrangement of collagen fibres in natural tendon and 3D bundles further replicated the tertiary layer of a tendon's hierarchical configuration. 3D bundles demonstrated greatest tensile properties, being significantly stronger and stiffer than 2D aligned and 2D random fibres. All scaffolds supported adhesion and proliferation of tendon fibroblasts. Furthermore, 2D aligned sheets and 3D bundles allowed guidance of the cells into a parallel, longitudinal arrangement, which is similar to tendon cells in the native tissue. With their superior physical properties and ability to better replicate tendon tissue, the 3D electrospun scaffolds warrant greater investigation as synthetic grafts in tendon repair. PMID:23504088

Bosworth, L A; Alam, N; Wong, J K; Downes, S

2013-06-01

275

The Tendon Network of the Fingers Performs Anatomical Computation at a Macroscopic Scale  

Microsoft Academic Search

Current thinking attributes information processing for neuromuscular control exclusively to the nervous system. Our cadaveric experiments and computer simulations show, however, that the tendon network of the fingers performs logic computation to preferentially change torque production capabilities. How this tendon network propagates tension to enable manipulation has been debated since the time of Vesalius and DaVinci and remains an unanswered

Francisco J. Valero-Cuevas; Jae-Woong Yi; Daniel Brown; Robert V. McNamara; Chandana Paul; Hood Lipson

2007-01-01

276

Intramuscular Rotator Cuff Cysts: Association with Tendon Tears on MRI and Arthroscopy  

Microsoft Academic Search

OBJECTIVE. This study was designed to explore the relationship between intramuscular cysts and rotator cuff tendon tears. CONCLUSION. Intramuscular cysts are strongly associated with rotator cuff tendon tears. Identification of such a cyst should prompt a search for a rotator cuff tear. Findings on MR arthrography and surgery suggest that a delaminating component of the rotator cuff tear may lead

Ara Kassarjian; Martin Torriani; Hugue Ouellette; William E. Palmer

277

Early response to tendon fatigue damage accumulation in a novel in vivo model  

PubMed Central

This study describes the development and application of a novel rat patellar tendon model of mechanical fatigue for investigating the early in vivo response to tendon subfailure injury. Patellar tendons of adult female Sprague-Dawley rats were fatigue loaded between 1–35 N using a custom-designed loading apparatus. Patellar tendons were subjected to Low-, Moderate- or High-level fatigue damage, defined by grip-to-grip strain measurement. Molecular response was compared with that of a laceration-repair injury. Histological analyses showed that progression of tendon fatigue involves formation of localized kinked fiber deformations at Low damage, which increased in density with presence of fiber delaminations at Moderate damage, and fiber angulation and discontinuities at High damage levels. RT-PCR analysis performed at 1- and 3-day post-fatigue showed variable changes in type I, III and V collagen mRNA expression at Low and Moderate damage levels, consistent with clinical findings of tendon pathology and were modest compared with those observed at High damage levels, in which expression of all collagens evaluated were increased markedly. In contrast, only type I collagen expression was elevated at the same time points post-laceration. Findings suggest that cumulative fatigue in tendon invokes a different molecular response than laceration. Further, structural repair may not be initiated until reaching end-stage fatigue life, where the repair response may unable to restore the damaged tendon to its pre-fatigue architecture. PMID:19939387

Fung, David T.; Wang, Vincent M.; Andarawis-Puri, Nelly; Basta-Pljakic, Jelena; Li, Yonghui; Laudier, Damien M.; Sun, Hui B.; Jepsen, Karl J.; Schaffler, Mitchell B.; Flatow, Evan L.

2012-01-01

278

The 3D structure of crimps in the rat Achilles tendon  

Microsoft Academic Search

The ultrastructure of crimps of the Achilles tendon of rat, excised and processed in a slack condition, was investigated by atomic force microscopy in air, in fluid and by scanning electron microscopy and stereo reconstruction. The tendon was made of distinct fascicles, each comprising a succession of straight segments connected by sharp angles. The length of the segments and the

Mario Raspanti; Alessandro Manelli; Marco Franchi; Alessandro Ruggeri

2005-01-01

279

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

ERIC Educational Resources Information Center

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

Virzi, Alison

2010-01-01

280

Rupture sous-cutan?e du tendon long extenseur du pouce: ? propos de 5 cas  

PubMed Central

La rupture spontanée du muscle long extenseur du pouce (EPL) du tendon au niveau du poignet est rare et principalement rapportés après fracture du radius distal à tubercule de Lister, dans la synovite, ténosynovite ou la polyarthrite rhumatoïde. Nous rapportons 5 cas de rupture spontanée du tendon long extenseur du pouce, traités par une greffe ou un transfert tendineux.

Abdelillah, Rachid; Abbassi, Najib; Erraji, Moncef; Abdeljawad, Najib; Yacoubi, Hicham; Daoudi, Abdelkrim

2014-01-01

281

Reconstruction of foot dorsiflexion using lateral arm free flap with vascularized triceps tendon  

Microsoft Academic Search

A lateral arm free flap including vascularized triceps tendon was transferred to reconstruct the tibialis anterior tendon and skin defects over the anterior distal third of the left cruris of a patient who was injured by gunshot. Four months after surgery, the patient walked and ran well, and dorsiflexed his ankle joint actively to 10°. Considering cosmetic appearance, it was

S. Akin; M. Özcan

1996-01-01

282

Double-bundle bone-patellar tendon-bone and gracilis in ACL reconstruction.  

PubMed

An original technique for the reconstruction of the anterior cruciate ligament is explained. Two bundles are reconstructed using the central third of the patellar tendon and the gracilis tendon, passed through four tunnels but requiring only two interference screws for fixation. Level of evidence V. PMID:22234785

Dejour, David; Ferrua, Paolo; Bonin, Nicolas; Saggin, Paulo Renato Fernandes

2012-11-01

283

In situ estimation of tendon material properties: Differences between muscles of the feline hindlimb  

E-print Network

University, 303 E. Chicago Avenue, Chicago, IL 60611, USA c Department of Physical Medicine to the skeleton, tendon plays an important role in other physiological features of muscle­tendon units (MTU, Pollock and Shadwick, 1994b). Also, the results from in vivo studies in humans suggest that the material

Perreault, Eric J.

284

Second harmonic generation imaging and Fourier transform spectral analysis reveal damage in fatigue-loaded tendons.  

PubMed

Conventional histologic methods provide valuable information regarding the physical nature of damage in fatigue-loaded tendons, limited to thin, two-dimensional sections. We introduce an imaging method that characterizes tendon microstructure three-dimensionally and develop quantitative, spatial measures of damage formation within tendons. Rat patellar tendons were fatigue loaded in vivo to low, moderate, and high damage levels. Tendon microstructure was characterized using multiphoton microscopy by capturing second harmonic generation signals. Image stacks were analyzed using Fourier transform-derived computations to assess frequency-based properties of damage. Results showed 3D microstructure with progressively increased density and variety of damage patterns, characterized by kinked deformations at low, fiber dissociation at moderate, and fiber thinning and out-of-plane discontinuities at high damage levels. Image analysis generated radial distributions of power spectral gradients, establishing a "fingerprint" of tendon damage. Additionally, matrix damage was mapped using local, discretized orientation vectors. The frequency distribution of vector angles, a measure of damage content, differed from one damage level to the next. This study established an objective 3D imaging and analysis method for tendon microstructure, which characterizes directionality and anisotropy of the tendon microstructure and quantitative measures of damage that will advance investigations of the microstructural basis of degradation that precedes overuse injuries. PMID:20232150

Fung, David T; Sereysky, Jedd B; Basta-Pljakic, Jelena; Laudier, Damien M; Huq, Rumana; Jepsen, Karl J; Schaffler, Mitchell B; Flatow, Evan L

2010-05-01

285

Tendon injuries induced by exercise and anabolic steroids in experimental mice  

Microsoft Academic Search

The purpose of this study was to examine the effect of anabolic steroid hormones and exercise training on skeletal tendons. Female mice were exercised for 1 and 10 weeks in an endurance running programme on a treadmill. The altered ultrastructure of tendons caused by simultaneously administered anabolic steroid hormone was investigated by electron microscopy. A stereoscopic analysis of collagen fibrils

H. Michna

1987-01-01

286

Rehabilitation of the Operated Achilles Tendon: Parameters for Predicting Return to Activity  

Microsoft Academic Search

Return to activity (RTA) following Achilles tendon surgery assessment criteria has not been generally adopted. A well-defined postsurgical rehabilitation regimen with 3 distinct criteria, yet easy to measure, can be used to assess the ability of patients undergoing Achilles tendon surgery to return to activity. We studied whether if patients were able to meet all 3 criteria, would this show

Amol Saxena; Brynn Ewen; Nicola Maffulli

2011-01-01

287

Biomechanical Evaluation of Acellular Collagen Matrix Augmented Achilles Tendon Repair in Sheep  

Microsoft Academic Search

The rate of rerupture of repaired Achilles tendon in young and athletic populations remains high despite improvement in surgical techniques, suture design, and postsurgical management. Acellular biological matrices can be used to enhance the immediate strength of repaired tendons and to serve as scaffolds for cell in-growth and constructive tissue remodeling. A number of commercially available matrices have been used

Lin Song; Raymond E. Olsen; Jeffrey P. Spalazzi; Twana Davisson

2010-01-01

288

Sonographic evaluation of achilles tendon thickness in elite track and field athletes: preliminary study  

Microsoft Academic Search

The purpose of the study was to measure Achilles tendon thickness in elite track and field athletes and to investigate any difference between dominant and non-dominant lower limb. Ultrasound examination of Achilles tendons was performed in 20 elite track and field athletes (12 males, 8 females; age range, 18–28 years). A control group of 20 healthy individuals, age and sex

Olga Kiritsi; Nikos Malliaropoulos; Konstantinos Tsitas; George Noussios

2011-01-01

289

Efficacy of Low Level Laser Therapy After Hand Flexor Tendon Repair  

Microsoft Academic Search

Flexor tendon injury is a common problem requiring suturing repair followed by early postoperative mobilization. Muscle atrophy, joint stiffness, osteoarthritis, infection, skin necrosis, ulceration of joint cartilage and tendocutaneous adhesion are familiar complications produced by prolonged immobilization of surgically repaired tendon ruptures. The purpose of this study was to clarify the importance of low level laser therapy after hand flexor

K. E. Ayad; H. M. El Gohary; M. Abd Elrahman; S. F. Abd El Mejeed; A. B. Bekheet

2009-01-01

290

Autogenous tendon graft substitution for absent knee joint meniscus: A pilot study  

Microsoft Academic Search

The purpose of this pilot study was to explore the potential of an autogenous tendon graft to substitute for an absent human knee joint meniscus. Based on the results of animal studies and human reports, it was hypothesized that autogenous tendon tissue would substitute for human knee joint meniscus: maintain mechanical integrity, convert to fibrocartilage, preserve the joint compartment, and

Lanny L. Johnson; John A. Feagin

2000-01-01

291

Structure and Functional Evaluation of Tendon-Skeletal Muscle Constructs Engineered in Vitro  

PubMed Central

During muscle contraction, the integrity of the myotendinous junction (MTJ) is important for the transmission of force from muscle to tendon. We evaluated the contractile and structural characteristics of 3-dimensional (3-D) skeletal muscle constructs co-cultured with engineered self-organized tendon constructs (n = 4), or segments of adult (n = 4) or fetal (n = 5) rat-tail tendon. We hypothesized that the co-culture of tendon and muscle would produce constructs with viable muscle–tendon interfaces that remain intact during generation of force. Construct diameter (?m) and maximum isometric force (?N) were measured, and specific force (kPa) was determined. After measure of force, constructs were loaded at a constant strain rate until failure and surface strains were recorded optically across the tendon, the muscle and the interface and used to determine the tangent modulus (passive stiffness) of the construct. Frozen samples were used for Trichrome Masson staining and immunofluorescent analysis of the MTJ-specific protein paxillin. No differences were observed between the groups with respect to diameter, maximum force, or specific force. The MTJ was robust and withstood tensile loading beyond the physiological strain range. The majority of the constructs failed in the muscle region. At the MTJ, there is an increase in the expression and localization of paxillin. In conclusion, using 3 sources of tendon tissue, we successfully engineered 3-D muscle–tendon constructs with functionally viable MTJ, characterized by structural features and protein expression patterns resembling neonatal MTJs in vivo. PMID:17518629

LARKIN, LISA M.; CALVE, SARAH; KOSTROMINOVA, TATIANA Y.; ARRUDA, ELLEN M.

2009-01-01

292

Collagen fibres of the spontaneously ruptured human tendons display decreased thickness and crimp angle  

Microsoft Academic Search

Purpose. To study collagen fibre thickness and crimp formation in healthy and ruptured human tendons.Methods. The thickness, crimp angle and wavelength of the collagen fibres were analyzed by interference and polarization microscopy and the samples were studied by transmission and scanning electron microscopy in four different healthy human tendons (Achilles, Quadriceps, Biceps brachii and Extensor pollicis longus) and in 66

Tero A. H. Järvinen; Teppo L. N. Järvinen; Pekka Kannus; László Józsa; Markku Järvinen

2004-01-01

293

A Cross-Sectional Study of the Plantar Flexor Muscle and Tendon during Growth.  

PubMed

The purpose of this study was to investigate growth changes in human plantar flexor muscle and tendons. In addition, we ascertained whether growth changes in muscle and tendon were more closely related to skeletal age than chronological age. 22 elementary school children (ESC), 19 junior high school students (JHS), and 23 young adults (ADT) men participated in this study. Maximal strain and hysteresis of tendon structures and cross-sectional area of Achilles tendon were measured using ultrasonography. In addition, skeletal age was assessed using Tanner-Whitehouse III method. Maximal strain of ESC was significantly greater than that of other groups, while no significant difference was observed between JHS and ADT. There was no difference in hysteresis among 3 groups. Relative cross-sectional area (to body mass(2/3)) of ADT was significantly smaller than that of other groups. For ESC and JHS, measured variables of muscle and tendon were significantly correlated to both chronological and skeletal ages. These results suggested that immature musculoskeletal system was protected by more extensible and larger tendon structures in ESC and only by larger tendon structures in JHS, respectively. Furthermore, there were no differences in correlation coefficient values between measured variables of muscle and tendon and chronological or skeletal ages. PMID:24577863

Kubo, K; Teshima, T; Hirose, N; Tsunoda, N

2014-09-01

294

Development of the human Achilles tendon enthesis organ  

PubMed Central

The attachment of the Achilles tendon is part of an ‘enthesis organ’ that reduces stress concentration at the hard–soft tissue interface. The organ also includes opposing sesamoid and periosteal fibrocartilages, a bursa and Kager's fat pad. In addition, the deep crural and plantar fasciae contribute to Achilles stress dissipation and could also be regarded as components. Here we describe the sequence in which these various tissues differentiate. Serial sections of feet from spontaneously aborted foetuses (crown rump lengths 22–322 mm) were examined. All slides formed part of an existing collection of histologically sectioned embryological material, obtained under Spanish law and housed in the Universidad Complutense, Madrid. From the earliest stages, it was evident that the Achilles tendon and plantar fascia had a mutual attachment to the calcaneal perichondrium. The first components of the enthesis organ to appear (in the 45-mm foetus) were the retrocalcaneal bursa and the crural fascia. The former developed by cavitation within the mesenchyme that later gave rise to Kager's fat pad. The tip of the putative fat pad protruded into the developing bursa in the 110-mm foetus and fully differentiated adipocytes were apparent in the 17-mm foetus. All three fibrocartilages were first recognisable in the 332-mm foetus – at which time adipogenesis had commenced in the heel fat pad. The sequence in which the various elements became apparent suggests that bursal formation and the appearance of the crural fascia may be necessary to facilitate the foot movements that subsequently lead to fibrocartilage differentiation. The later commencement of adipogenesis in the heel than in Kager's pad probably reflects the non-weight environment in utero. The direct continuity between plantar fascia and Achilles tendon that is characteristic of the adult reflects the initial attachment of both structures to the calcaneal perichondrium rather than to the skeletal anlagen itself. PMID:19094187

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

2008-01-01

295

Variability in Hoffmann and tendon reflexes in healthy male subjects  

NASA Technical Reports Server (NTRS)

There is a time dependent decrease in amplitude of H- and T-reflexes during Zero-G exposure and subsequently an increase in the amplitude of the H-reflex 2-4 hours after return to a 1-G environment. These alterations have been attributed to the adaptation of the human neurosensory system to gravity. The Hoffman reflex (H-reflex) is an acknowledged method to determine the integrity of the monosynaptic reflex arc. However deep tendon reflexes (DTR's or T-reflexes), elicited by striking the tendon also utilize the entire reflex arc. The objective of this study was to compare the variability in latency and amplitude of the two reflexes in healthy subjects. Methods: Nine healthy male subjects, 27-43 years in age, 161-175 cm in height plus 60-86 Kg in weight, underwent weekly testing for four weeks with a Dan-Tec EMG counterpoint EMG system. Subjects were studied prone and surface EMG electrodes were placed on the right and left soleus muscles. The H-reflex was obtained by stimulating the tibial nerve in the politeal fossa with a 0.2 msec square wave pulse delivered at 2 Hz until the maximum H-reflex was obtained. The T-reflex was invoked by tapping the achilles tendon with a self triggering reflex hammer connected to the EMG system. The latencies and amplitudes for the H- and T-reflexes were measured. Results: These data indicate that the amplitudes of these reflexes varied considerably. However, latencies to invoked responses were consistent. The latency of the T-reflex was approximately 3-5 msec longer than the H-reflex. Conclusion: The T-reflex is easily obtained, requires less time, and is more comfortable to perform. Qualitative data can be obtained by deploying self triggering, force plated reflex hammers both in the 1-G and Zero-G environment.

Good, E.; Do, S.; Jaweed, M.

1992-01-01

296

Giant cell tumor of the tendon sheath extending around the patellar tendon and invading the knee joint and tibia: A case report  

PubMed Central

The current report presents the case of a 41-year-old male exhibiting a giant cell tumor of the tendon sheath (GCT-TS) arising from the patellar tendon sheath. Plain radiography and magnetic resonance imaging revealed a well-localized mass that wrapped around the patellar tendon, and extended from the subcutis into the infrapatellar fat pad and tibia. Following histopathological determination of the diagnosis, a piecemeal resection was performed. Nodular-type GCT-TS occurs less frequently in large joints compared with the small joints of the fingers and toes. The current report presents the unique features of a case of GCT-TS extending around the patellar tendon, and invading into the knee joint and proximal tibia bone.

AKAHANE, TSUTOMU; MORI, NAOYA; YOSHIDA, KAZUSHIGE

2014-01-01

297

In vivo motion transmission in the inactive gastrocnemius medialis muscle–tendon unit during ankle and knee joint rotation  

Microsoft Academic Search

The purposes of this study were: (a) to quantify the influence of passive ankle and knee joint angular displacement on the estimated mechanical and architectural properties of the gastrocnemius medialis (GM) muscle–tendon unit, and (b) to determine the strain distribution of separate structures (tendon, aponeurosis and fascicle) during passive lengthening of the GM muscle–tendon unit at rest. Ten male subjects

Gianpiero De Monte; Adamantios Arampatzis; Chrissa Stogiannari; Kiros Karamanidis

2006-01-01

298

The Effects of Donor Age and Strain Rate on the Biomechanical Properties of Bone-Patellar Tendon-Bone Allografts  

Microsoft Academic Search

Over 50% of all knee injuries involve partial or com plete tear of the anterior cruciate ligament. Surgical reconstruction of this ligament using an isometrically placed bone-patellar tendon-bone autograft is the cur rent technique of choice; however, harvest of patellar tendon as a free graft can lead to increased morbidity. To address this issue, allogenic patellar tendon grafts have been

Field T. Blevins; Aaron T. Hecker; Gregory T. Bigler; Arthur L. Boland; Wilson C. Hayes

1994-01-01

299

Neovascularisation in chronic tendon injuries detected with colour Doppler ultrasound in horse and man: implications for research and treatment  

Microsoft Academic Search

Recent research on chronic painful Achilles tendons in humans using ultrasonography and immunohistochemistry, has demonstrated an association between neurovascular ingrowth and tendon pain. In horses, chronic debilitating tendon conditions are well-known to be very difficult to treat, and the background to impaired function and pain is not scientifically clarified. In a collaborative research project between the Sports Medicine Unit in

Mads Kristoffersen; Lars Öhberg; Christopher Johnston; Håkan Alfredson

2005-01-01

300

Tendon tissue engineering: adipose-derived stem cell and GDF-5 mediated regeneration using electrospun matrix systems  

Microsoft Academic Search

Tendon tissue engineering with a biomaterial scaffold that mimics the tendon extracellular matrix (ECM) and is biomechanically suitable, and when combined with readily available autologous cells, may provide successful regeneration of defects in tendon. Current repair strategies using suitable autografts and freeze-dried allografts lead to a slow repair process that is sub-optimal and fails to restore function, particularly in difficult

R. James; S. G. Kumbar; C. T. Laurencin; G. Balian; A. B. Chhabra

2011-01-01

301

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

Microsoft Academic Search

In studies intended to improve healing of transected Achilles tendon, effective was a stable gastric pentadecapeptide BPC 157 (GEPPPGKPADDAGLV, M.W. 1419). Currently in clinical trials for inflammatory bowel disease (PLD-116, PL 14736, Pliva), it ameliorates internal and external wound healing. In rats, the right Achilles tendon transected (5 mm proximal to its calcaneal insertion) presents with a large tendon defect

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

2003-01-01

302

MR imaging of delamination tears of the rotator cuff tendons  

Microsoft Academic Search

Objective  The objective was to describe the imaging appearances and location of delamination tears of the rotator cuff tendons on non-contrast\\u000a conventional MR imaging.\\u000a \\u000a \\u000a \\u000a Subjects and methods  This study was reviewed and approved by our Institutional Review Board. The reports of 548 consecutive MR examinations of\\u000a the shoulder were reviewed, looking for mention or description of delamination tears of the rotator cuff.

Daniel M. Walz; Theodore T. Miller; Steven Chen; Josh Hofman

2007-01-01

303

Effects of fluoride on in vitro calcification of tendon matrix  

Microsoft Academic Search

Summary Ca2+ and Pi uptake induced in vitro by a collagenous matrix derived from bovine tendon is inhibited by 1×10?6 to 2×10?5M NaF and stimulated by 2×10?5 to 2×10?3M NaF. Fluoride uptake occurs only over the latter concentrtion range. The uptake of Ca2+, Pi, and F?1 progresses toward a limiting extent at which the molar Ca\\/P and Ca\\/F values are

C. L. Wadkins; R. A. Luben

1978-01-01

304

Indicators of replicative damage in equine tendon fibroblast monolayers  

PubMed Central

Background Superficial digital flexor tendon (SDFT) injuries of horses usually follow cumulative matrix microdamage; it is not known why the reparative abilities of tendon fibroblasts are overwhelmed or subverted. Relevant in vitro studies of this process require fibroblasts not already responding to stresses caused by the cell culture protocols. We investigated indicators of replicative damage in SDFT fibroblast monolayers, effects of this on their reparative ability, and measures that can be taken to reduce it. Results We found significant evidence of replicative stress, initially observing consistently large numbers of binucleate (BN) cells. A more variable but prominent feature was the presence of numerous gammaH2AX (?H2AX) puncta in nuclei, this being a histone protein that is phosphorylated in response to DNA double-stranded breaks (DSBs). Enrichment for injury detection and cell cycle arrest factors (p53 (ser15) and p21) occurred most frequently in BN cells; however, their numbers did not correlate with DNA damage levels and it is likely that the two processes have different causative mechanisms. Such remarkable levels of injury and binucleation are usually associated with irradiation, or treatment with cytoskeletal-disrupting agents. Both DSBs and BN cells were greatest in subconfluent (replicating) monolayers. The DNA-damaged cells co-expressed the replication markers TPX2/repp86 and centromere protein F. Once damaged in the early stages of culture establishment, fibroblasts continued to express DNA breaks with each replicative cycle. However, significant levels of cell death were not measured, suggesting that DNA repair was occurring. Comet assays showed that DNA repair was delayed in proportion to levels of genotoxic stress. Conclusions Researchers using tendon fibroblast monolayers should assess their “health” using ?H2AX labelling. Continued use of early passage cultures expressing initially high levels of ?H2AX puncta should be avoided for mechanistic studies and ex-vivo therapeutic applications, as this will not be resolved with further replicative cycling. Low density cell culture should be avoided as it enriches for both DNA damage and mitotic defects (polyploidy). As monolayers differing only slightly in baseline DNA damage levels showed markedly variable responses to a further injury, studies of effects of various stressors on tendon cells must be very carefully controlled. PMID:24025445

2013-01-01

305

Congenital defects of the flexor digitorum profundus tendon of the little finger.  

PubMed

The cases of two patients, a four-year-old boy and an eight-year-old boy, who had been incapable of active flexion of the little finger since birth, are presented. They were capable of active flexion of the metacarpophalangeal (MP) joint, but not of the proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints. They were diagnosed with a defect of the flexor digitorum profundus (FDP) tendon of the little finger and underwent surgery. In both cases, the FDP tendon turned into fibrous tissue proximal to the palm and lost continuity on this side. Reconstruction was performed by making an end-to-side anastomosis of the residual proximal end of the FDP tendon to the FDP tendon of the ring finger in the palmar region. Although one patient required repeated surgery due to post-operative tendon adhesion, good outcomes were achieved, with both patients becoming capable of active flexion. PMID:24875514

Fukuoka, Masatoshi; Takayama, Shinichiro; Seki, Atuhito

2014-01-01

306

Injury induces a change in the functional characteristics of cells recovered from equine tendon.  

PubMed

Injury initiates a repair process characterized by influx of fibroblasts and the rapid formation of fibrous scar tissue and subsequent tissue contraction. The response to injury and behavior of the different tendon fibroblast populations, however, has been poorly characterized. We hypothesized that the fibroblasts recovered from tendon with acute injury would exhibit different cell properties relating to adhesion, migration and tensegrity. To test this hypothesis we evaluated the ability of fibroblasts recovered from normal and injured equine superficial digital flexor tendons (SDFTs). The injured tendon-derived cells showed greater contraction of the collagen gel but poorer adhesion to pepsin-digested collagen, and migration over extracellular matrix proteins compared to normal SDFT-derived fibroblasts. Thus, the cells present within the tendon after injury display different behavior related to wound healing. PMID:24833988

Kihara, Rina; Kasashima, Yoshinori; Arai, Katsuhiko; Miyamoto, Yasunori

2011-01-01

307

Spontaneous rupture of EPL and ECRB tendons in a washerwoman: an unusual phenomenon.  

PubMed

Spontaneous rupture of the extensor pollicis longus (EPL) tendon is rare, and spontaneous non-traumatic rupture of both extensor pollicis longus (EPL) and extensor carpi radialis brevis (ECRB) tendons is not reported in literature. Rupture of EPL is usually associated with rheumatoid arthritis, systemic or local steroid injections, fractures of the wrist and repetitive and excessive abnormal motion of the wrist joint. We describe a case of spontaneous rupture of the EPL and ECRB tendons in a female patient, washerwoman by occupation, with no predisposing factor. Exploration of the tendons along with end to end tendon repair was done with excellent results. We describe the possible mechanism of the injury and result after one year follow up. PMID:24875511

Jain, Anuj; Goyal, Naveen; Mishra, Puneet

2014-01-01

308

Sonographic findings during and after Platelet Rich Plasma injections in tendons  

PubMed Central

Summary Platelet rich plasma has been used in the treatment of tendinopathies, but the sonographic modifications of tendons have received less attention. In this paper we report the results of an ultrasound evaluation, performed during and after plasma injection, in patients with tendinopathy. The sonographic abnormalities and neovascularization were registered in twenty tendons. Three plasma injections (once a week) were performed, and a rehabilitation program was recommended. Pain and patients’ satisfaction were evaluated. During the injections plasma spread along the collagen fibers, and an intratendineous cleft produced by the injected volume was observed. At 12 months two tendons regained a normal echotexture, while neovessels were absent in seven. The remaining tendons showed less abnormalities and neovascularization in comparison with baseline. The clinical improvement was earlier and more consistent. The discrepancy between the ultrasound and clinical results may be explained by the peculiar modalities of tendon healing induced by plasma administration. PMID:24932444

Abate, Michele; Verna, Sandra; Di Gregorio, Patrizia; Salini, Vincenzo; Schiavone, Cosima

2014-01-01

309

Is initial preservation of deep tendon reflexes in West Nile Virus paralysis a good prognostic sign?  

PubMed Central

Typical West Nile virus paralysis is characterized by muscle weakness, decreased tone, and loss of deep tendon reflexes attributed to destruction of anterior horn cells. Two cases in which deep tendon reflexes were initially preserved in the presence of profound and persistent muscle weakness are presented here. In both cases, deep tendon reflexes were later severely attenuated or lost, while weakness of the involved muscles remained profound and unchanged. Both patients showed good motor recovery at 6 months. Initial preservation of deep tendon reflexes in the presence of persistent muscle weakness indicates that in the early stages of disease, the muscle weakness in these two cases was not caused by destruction of anterior horn cells. Pathology involving anterior horns preceding AHC destruction could potentially disrupt upper motor neuron pathways to anterior horn cells, causing weakness with initial preserved deep tendon reflexes.

Mojumder, Deb Kumar; Agosto, Melina; Wilms, Henrik; Kim, Jongyeol

2014-01-01

310

Isokinetic quadriceps and hamstring muscle strength and knee function 5 years after anterior cruciate ligament reconstruction: comparison between bone-patellar tendon-bone and hamstring tendon autografts  

Microsoft Academic Search

Existing clinical studies have not proven which graft is to be preferred in anterior cruciate ligament (ACL) reconstruction.\\u000a In recent years, bone-patellar tendon-bone and hamstring tendons have been the most frequently used graft types. Muscle strength\\u000a deficit is one of the consequences after ACL reconstruction. The aim of this study was to evaluate possible differences in\\u000a hamstring and quadriceps muscle

Riitta Lautamies; Arsi Harilainen; Jyrki Kettunen; Jerker Sandelin; Urho M. Kujala

2008-01-01

311

Salvage options for flexor carpi radialis tendon disruption during ligament reconstruction and tendon interposition or suspension arthroplasty of the trapeziometacarpal joint.  

PubMed

Several techniques of thumb basilar joint arthroplasty depend on an intact flexor carpi radialis (FCR) tendon. There are situations, however, when the FCR tendon may be attenuated or iatrogenically injured, which make these techniques difficult or unfeasible. Familiarity with intraoperative salvage techniques in this setting is imperative. We present techniques for stabilizing the base of the thumb metacarpal when the FCR is deficient or injured. PMID:23928018

Jones, David B; Rhee, Peter C; Shin, Alexander Y; Kakar, Sanjeev

2013-09-01

312

Effects of resistance training on tendon mechanical properties and rapid force production in prepubertal children.  

PubMed

Children develop lower levels of muscle force, and at slower rates, than adults. Although strength training in children is expected to reduce this differential, a synchronous adaptation in the tendon must be achieved to ensure forces continue to be transmitted to the skeleton with efficiency while minimizing the risk of strain-related tendon injury. We hypothesized that resistance training (RT) would alter tendon mechanical properties in children concomitantly with changes in force production characteristics. Twenty prepubertal children (age 8.9 ± 0.3 yr) were equally divided into control (nontraining) and experimental (training) groups. The training group completed a 10-wk RT intervention consisting of 2-3 sets of 8-15 plantar flexion contractions performed twice weekly on a recumbent calf-raise machine. Achilles tendon properties (cross-sectional area, elongation, stress, strain, stiffness, and Young's modulus), electromechanical delay (EMD; time between the onset of muscle activity and force), rate of force development (RFD; slope of the force-time curve), and rate of electromyographic (EMG) increase (REI; slope of the EMG time curve) were measured before and after RT. Tendon stiffness and Young's modulus increased significantly after RT in the experimental group only (?29% and ?25%, respectively); all other tendon properties were not significantly altered, although there were mean decreases in both peak tendon strain and strain at a given force level (14% and 24%, respectively; not significant) which may have implications for tendon injury risk and muscle fiber mechanics. A decrease of ?13% in EMD was found after RT for the experimental group, which paralleled the increase in tendon stiffness (r = -0.59); however, RFD and REI were unchanged. The present data show that the Achilles tendon adapts to RT in prepubertal children and is paralleled by a change in EMD, although the magnitude of this change did not appear to be sufficient to influence RFD. These findings are of importance within the context of the efficiency and execution of movement. PMID:24903920

Waugh, C M; Korff, T; Fath, F; Blazevich, A J

2014-08-01

313

Effects of resistance training on tendon mechanical properties and rapid force production in prepubertal children  

PubMed Central

Children develop lower levels of muscle force, and at slower rates, than adults. Although strength training in children is expected to reduce this differential, a synchronous adaptation in the tendon must be achieved to ensure forces continue to be transmitted to the skeleton with efficiency while minimizing the risk of strain-related tendon injury. We hypothesized that resistance training (RT) would alter tendon mechanical properties in children concomitantly with changes in force production characteristics. Twenty prepubertal children (age 8.9 ± 0.3 yr) were equally divided into control (nontraining) and experimental (training) groups. The training group completed a 10-wk RT intervention consisting of 2–3 sets of 8–15 plantar flexion contractions performed twice weekly on a recumbent calf-raise machine. Achilles tendon properties (cross-sectional area, elongation, stress, strain, stiffness, and Young's modulus), electromechanical delay (EMD; time between the onset of muscle activity and force), rate of force development (RFD; slope of the force-time curve), and rate of electromyographic (EMG) increase (REI; slope of the EMG time curve) were measured before and after RT. Tendon stiffness and Young's modulus increased significantly after RT in the experimental group only (?29% and ?25%, respectively); all other tendon properties were not significantly altered, although there were mean decreases in both peak tendon strain and strain at a given force level (14% and 24%, respectively; not significant) which may have implications for tendon injury risk and muscle fiber mechanics. A decrease of ?13% in EMD was found after RT for the experimental group, which paralleled the increase in tendon stiffness (r = ?0.59); however, RFD and REI were unchanged. The present data show that the Achilles tendon adapts to RT in prepubertal children and is paralleled by a change in EMD, although the magnitude of this change did not appear to be sufficient to influence RFD. These findings are of importance within the context of the efficiency and execution of movement. PMID:24903920

Waugh, C. M.; Korff, T.; Fath, F.

2014-01-01

314

Force transmission via axial tendons in undulating fish: a dynamic analysis.  

PubMed

Sonomicrometrics of in vivo axial strain of muscle has shown that the swimming fish body bends like a homogenous, continuous beam in all species except tuna. This simple beam-like behavior is surprising because the underlying tendon structure, muscle structure and behavior are complex. Given this incongruence, our goal was to understand the mechanical role of various myoseptal tendons. We modeled a pumpkinseed sunfish, Lepomis gibbosus, using experimentally-derived physical and mechanical attributes, swimming from rest with steady muscle activity. Axially oriented muscle-tendons, transverse and axial myoseptal tendons, as suggested by current morphological knowledge, interacted to replicate the force and moment distribution. Dynamic stiffness and damping associated with muscle activation, realistic muscle force generation, and force distribution following tendon geometry were incorporated. The vertebral column consisted of 11 rigid vertebrae connected by joints that restricted bending to the lateral plane and endowed the body with its passive viscoelasticity. In reaction to the acceleration of the body in an inviscid fluid and its internal transmission of moment via the vertebral column, the model predicted the kinematic response. Varying only tendon geometry and stiffness, four different simulations were run. Simulations with only intrasegmental tendons produced unstable axial and lateral tail forces and body motions. Only the simulation that included both intra- and intersegmental tendons, muscle-enhanced segment stiffness, and a stiffened caudal joint produced stable and large lateral and axial forces at the tail. Thus this model predicts that axial tendons function within a myomere to (1) convert axial force to moment (moment transduction), (2) transmit axial forces between adjacent myosepta (segment coupling), and, intersegmentally, to (3) distribute axial forces (force entrainment), and (4) stiffen joints in bending (flexural stiffening). The fact that all four functions are needed to produce the most realistic swimming motions suggests that axial tendons are essential to the simple beam-like behavior of fish. PMID:12485683

Long, John H; Adcock, Bruce; Root, Robert G

2002-12-01

315

Repair of the torn distal biceps tendon by endobutton fixation  

PubMed Central

Background: A number of techniques have been described to reattach the torn distal biceps tendon to the bicipital tuberosity. We report a retrospective analysis of single incision technique using an endobutton fixation in sports persons. Materials and Methods: The present series include nine torn distal biceps tendons in eight patients, fixed anatomically to the radial tuberosity with an endobutton by using a single incision surgical technique; seven patients had suffered the injuries during contact sports. The passage of the endobutton was facilitated by using a blunt tipped pin in order to avoid injury to the posterior interosseous nerve. The patients were evaluated by Disabilities of the Arm, Shoulder and Hand (DASH) score and Mayo elbow score. Results: The average age of the patients was 27.35 years (range 21–42 years). Average follow-up was 41.5 months (range 24–102 months). The final average flexion extension arc was 0°–143°, while the average pronation and supination angles were 77° (range 70°–82°) and 81° (range 78°–85°), respectively at the last followup. All the patients had a Disabilities of the Arm, Shoulder and Hand (DASH) score of 0 and a Mayo elbow score of 100 each. All the seven active sports persons were able to get back to their respective game. There was no nerve injury or any other complication. Conclusions: The surgical procedure used by us is a simple, safe and reproducible technique giving minimal morbidity and better cosmetic results. PMID:22345810

Gupta, Ravi K; Bither, Nitin; Singh, Harpreet; Kapoor, Saurabh; Chhabra, Ashish; Garg, Sudhir

2012-01-01

316

New method for fixation point of tibialis posterior tendon transfer  

PubMed Central

Background The transfer of the tibialis posterior tendon to the dorsum of foot can restore the function of theparalyzed dorsiflexor muscles of the foot and ankle. In order to reduce the wound complication in the insertionsite of tendon to bone by a plantar knop we used a new method of fixation by an absorbable screw inserted dorsally. Methods we performed this operation on 15 patients in a 3 years period. All patients had drop foot deformitydue to irreversible lesions of the peroneal nerve. The inclusion criteria was the peroneal nerve palsy that wasnot improved after 18 months even by using nerve releasing or nerve repairing. All patients were evaluatedafter 6 months for ankle function and wound complications. Result Of 15 patients one was excluded from study. At 6 month ten patients got excellent score (66%) and 4good score (26%) further ankle function. There was no wound complication at insertion site Conclusion This simple modification for insertion site fixation had good result in restoring ankle functionwhiles eliminated the possibility of plantar pressure sores caused by fixation knop. PMID:24926176

Yeganeh, Ali; Motaghi, Arash; Shahhoseini, Gholamreza; Farahini, Hosein

2013-01-01

317

Fiber optic micro sensor for the measurement of tendon forces  

PubMed Central

A fiber optic sensor developed for the measurement of tendon forces was designed, numerically modeled, fabricated, and experimentally evaluated. The sensor incorporated fiber Bragg gratings and micro-fabricated stainless steel housings. A fiber Bragg grating is an optical device that is spectrally sensitive to axial strain. Stainless steel housings were designed to convert radial forces applied to the housing into axial forces that could be sensed by the fiber Bragg grating. The metal housings were fabricated by several methods including laser micromachining, swaging, and hydroforming. Designs are presented that allow for simultaneous temperature and force measurements as well as for simultaneous resolution of multi-axis forces. The sensor was experimentally evaluated by hydrostatic loading and in vitro testing. A commercial hydraulic burst tester was used to provide uniform pressures on the sensor in order to establish the linearity, repeatability, and accuracy characteristics of the sensor. The in vitro experiments were performed in excised tendon and in a dynamic gait simulator to simulate biological conditions. In both experimental conditions, the sensor was found to be a sensitive and reliable method for acquiring minimally invasive measurements of soft tissue forces. Our results suggest that this sensor will prove useful in a variety of biomechanical measurements. PMID:23033868

2012-01-01

318

[Bilateral rupture of the Achilles tendon--an unusual occurrence].  

PubMed

We present the clinical case of a sixty-four-year-old man with bilateral spontaneous rupture of the Achilles tendon having a multiple disseminated oesophagus carcinoma. After immobilisation due to metastases of the 2nd lumbar vertebra, there was a spontaneous, painless rupture of the Achilles tendon while the patient was mobilised wearing a Hohmann spine brace. Afterwards we carried out a thorough case history with the help of clinical examination, sonographic and magnetic resonance imaging. The bilateral rupture has been treated conservatively with the Adipromed Shoe. With regard to the 2nd lumbar vertebra fracture and metastases, a Hohmann spine brace was given to the patient. Because of the described circumstances, no surgery had been carried out. Furthermore, the patient experienced much more independence and an improved quality of life in his last couple of months. Surgery would have not been recommended and could have caused the complete immobilisation and loss of patient's quality of life. With this case report we would like to point out the consequences of an unwise therapeutic decision to a patient who only has a few more months to live. This case report is discussed with regard to the possible aetiopathology and the current literature. PMID:16991068

Schikora, N; Delank, K-S; Gärtner, J; Eysel, P

2006-01-01

319

[Early functional treatment of surgically managed Achilles tendon rupture].  

PubMed

40 acute traumatic ruptures of the Achilles tendon were evaluated in a prospective study after open repair using an early functional rehabilitation protocol. The age of the patients averaged 43 (23-64) years. The operation consisted of a Kessler suture and microadaptation of the tendon. A special boot was used for after treatment. The boot was used 9 (1-18) weeks and full weight bearing was reported after 7 (1-16) weeks. The sick leave time averaged 5.5 (0-18) weeks. After 1 year, length and ankle joint motion were restored. Outcome was assessed using a 100-point score described by Thermann. After 4 months it averaged 73.5 +/- 15.5 points and after 1 year 94.5 +/- 6.0 points. There were no perioperative complications. One rerupture occurred 6 weeks postoperatively and was operated successfully. The combination of surgical repair and early functional after treatment resulted in normal function after 1 year, but requires cooperation of the patient. PMID:12243015

Schäfer, D; Regazzoni, P; Hintermann, B

2002-08-01

320

Spatial and Temporal Expression of Molecular Markers and Cell Signals During Normal Development of the Mouse Patellar Tendon  

PubMed Central

Tendon injuries are common clinical problems and are difficult to treat. In particular, the tendon-to-bone insertion site, once damaged, does not regenerate its complex zonal arrangement. A potential treatment for tendon injuries is to replace injured tendons with bioengineered tendons. However, the bioengineering of tendon will require a detailed understanding of the normal development of tendon, which is currently lacking. Here, we use the mouse patellar tendon as a model to describe the spatial and temporal pattern of expression of molecular markers for tendon differentiation from late fetal life to 2 weeks after birth. We found that collagen I, fibromodulin, and tenomodulin were expressed throughout the tendon, whereas tenascin-C, biglycan, and cartilage oligomeric protein were concentrated in the insertion site during this period. We also identified signaling pathways that are activated both throughout the developing tendon, for example, transforming growth factor beta and bone morphogenetic protein, and specifically in the insertion site, for example, hedgehog pathway. Using a mouse line expressing green fluorescent protein in all tenocytes, we also found that tenocyte cell proliferation occurs at highest levels during late fetal life, and declines to very low levels by 2 weeks after birth. These data will allow both the functional analysis of specific signaling pathways in tenocyte development and their application to tissue-engineering studies in vitro. PMID:21939397

Liu, Chia-Feng; Aschbacher-Smith, Lindsey; Barthelery, Nicolas J.; Dyment, Nathaniel; Butler, David

2012-01-01

321

Ultrasonographic measurement of tendon displacement caused by active force generation in the psoas major muscle.  

PubMed

The purpose of this study was to examine the validity of using ultrasonography for detecting the force generated by the psoas major muscle, a muscle positioned in the deep trunk. We measured the displacement of central tendon on B-mode ultrasound images of two different longitudinal sections of the muscle during passive hip flexion-extension and isometric hip flexion at varied hip angles. In both tasks, the values of tendon displacement obtained independently from each section coincided well, indicating that tendon displacement took place along a straight trajectory, i.e., close to the nodal line between two scanned planes. It was strongly correlated with both the hip angle (R(2) = 0.98) and the hip-flexion torque (R(2) = 0.83). In the second set of experiment, we measured the tendon displacement during dynamic movements with the combination of ultrasonography and VICON-based motion analysis. From the tendon displacement during dynamic thigh lifting and walking, the force generated by the muscle could be estimated by extracting the force-related component. These results indicate that ultrasonography of the psoas major muscle can measure the displacement of its central tendon accompanied with either length change of the muscle or the elongation of tendon. Although much attention has to be paid to the limitations of this methodology, ultrasonography may be useful for detecting the force generation of the muscle during a variety of dynamic movements. PMID:18840323

Matsubayashi, Takeo; Kubo, Junjiro; Matsuo, Akifumi; Kobayashi, Kando; Ishii, Naokata

2008-10-01

322

Fetal and adult fibroblasts display intrinsic differences in tendon tissue engineering and regeneration.  

PubMed

Injured adult tendons do not exhibit optimal healing through a regenerative process, whereas fetal tendons can heal in a regenerative fashion without scar formation. Hence, we compared FFs (mouse fetal fibroblasts) and AFs (mouse adult fibroblasts) as seed cells for the fabrication of scaffold-free engineered tendons. Our results demonstrated that FFs had more potential for tendon tissue engineering, as shown by higher levels of tendon-related gene expression. In the in situ AT injury model, the FFs group also demonstrated much better structural and functional properties after healing, with higher levels of collagen deposition and better microstructure repair. Moreover, fetal fibroblasts could increase the recruitment of fibroblast-like cells and reduce the infiltration of inflammatory cells to the injury site during the regeneration process. Our results suggest that the underlying mechanisms of better regeneration with FFs should be elucidated and be used to enhance adult tendon healing. This may assist in the development of future strategies to treat tendon injuries. PMID:24992450

Tang, Qiao-Mei; Chen, Jia Lin; Shen, Wei Liang; Yin, Zi; Liu, Huan Huan; Fang, Zhi; Heng, Boon Chin; Ouyang, Hong Wei; Chen, Xiao

2014-01-01

323

The Use of Hyaluronic Acid after Tendon Surgery and in Tendinopathies  

PubMed Central

Viscosupplementation with hyaluronic acid is safe and effective in the management of osteoarthritis, but its use in the treatment of tendon disorders has received less attention. The aim of this review is to summarize the current knowledge on this topic, evaluating experimental and clinical trials. A search of English-language articles was performed using the key search terms “hyaluronic acid” or “viscosupplementation” combined with “tendon,” “tendinopathy,“ “adhesions,“ or “gliding,“ independently. In quite all the experimental studies, performed after surgical procedures for tendon injuries or in the treatment of chronic tendinopathies, using different hyaluronic acid compounds, positive results (reduced formation of scars and granulation tissue after tendon repair, less adhesions and gliding resistance, and improved tissue healing) were observed. In a limited number of cases, hyaluronic acid has been employed in clinical practice. After flexor tendon surgery, a greater total active motion and fingers function, with an earlier return to work and daily activities, were observed. Similarly, in patients suffering from elbow, patellar, and shoulder tendons disorders, pain was reduced, and function improved. The positive effect of hyaluronic acid can be attributed to the anti-inflammatory activity, enhanced cell proliferation, and collagen deposition, besides the lubricating action on the sliding surface of the tendon. PMID:24895610

Schiavone, Cosima; Salini, Vincenzo

2014-01-01

324

Structural changes in loaded equine tendons can be monitored by a novel spectroscopic technique  

PubMed Central

This study aimed to investigate the preferential collagen fibril alignment in unloaded and loaded tendons using elastic scattering spectroscopy. The device consisted of an optical probe, a pulsed light source (320–860 nm), a spectrometer and a PC. Two probes with either 2.75 mm or 300 ?m source-detector separations were used to monitor deep and superficial layers, respectively. Equine superficial digital flexor tendons were subjected to ex vivo progressive tensional loading. Seven times more backscattered light was detected parallel rather than perpendicular to the tendon axis with the 2.75 mm separation probe in unloaded tendons. In contrast, using the 300 ?m separation probe the plane of maximum backscatter (3-fold greater) was perpendicular to the tendon axis. There was no optical anisotropy in the cross-sectional plane of the tendon (i.e. the transversely cut tendon surface), with no structural anisotropy. During mechanical loading (9–14% strain) backscatter anisotropy increased 8.5- to 18.5-fold along the principal strain axis for 2.75 mm probe separation, but almost disappeared in the perpendicular plane (measured using the 300 ?m probe separation). Optical (anisotropy) and mechanical (strain) measurements were highly correlated. We conclude that spatial anisotropy of backscattered light can be used for quantitative monitoring of collagen fibril alignment and tissue reorganization during loading, with the potential for minimally invasive real-time structural monitoring of fibrous tissues in normal, pathological or repairing tissues and in tissue engineering. PMID:14578479

Kostyuk, Oksana; Birch, Helen L; Mudera, Vivek; Brown, Robert A

2004-01-01

325

Fetal and adult fibroblasts display intrinsic differences in tendon tissue engineering and regeneration  

PubMed Central

Injured adult tendons do not exhibit optimal healing through a regenerative process, whereas fetal tendons can heal in a regenerative fashion without scar formation. Hence, we compared FFs (mouse fetal fibroblasts) and AFs (mouse adult fibroblasts) as seed cells for the fabrication of scaffold-free engineered tendons. Our results demonstrated that FFs had more potential for tendon tissue engineering, as shown by higher levels of tendon-related gene expression. In the in situ AT injury model, the FFs group also demonstrated much better structural and functional properties after healing, with higher levels of collagen deposition and better microstructure repair. Moreover, fetal fibroblasts could increase the recruitment of fibroblast-like cells and reduce the infiltration of inflammatory cells to the injury site during the regeneration process. Our results suggest that the underlying mechanisms of better regeneration with FFs should be elucidated and be used to enhance adult tendon healing. This may assist in the development of future strategies to treat tendon injuries. PMID:24992450

Tang, Qiao-Mei; Chen, Jia Lin; Shen, Wei Liang; Yin, Zi; Liu, Huan Huan; Fang, Zhi; Heng, Boon Chin; Ouyang, Hong Wei; Chen, Xiao

2014-01-01

326

Tendon Tissue Engineering and Its Role on Healing of the Experimentally Induced Large Tendon Defect Model in Rabbits: A Comprehensive In Vivo Study  

PubMed Central

Healing of large tendon defects is challenging. We studied the role of collagen implant with or without polydioxanone (PDS) sheath on the healing of a large Achilles tendon defect model, in rabbits. Sixty rabbits were divided into three groups. A 2 cm gap was created in the left Achilles tendon of all rabbits. In the control lesions, no implant was used. The other two groups were reconstructed by collagen and collagen-PDS implants respectively. The animals were clinically examined at weekly intervals and their lesions were observed by ultrasonography. Blood samples were obtained from the animals and were assessed for hematological analysis and determination of serum PDGF level, at 60 days post injury (DPI). The animals were then euthanized and their lesions were assessed for gross and histopathology, scanning electron microscopy, biomechanical testing, dry matter and hydroxyproline content. Another 65 pilot animals were also studied grossly and histopathologically to define the host implant interaction and graft incorporation at serial time points. The treated animals gained significantly better clinical scoring compared to the controls. Treatment with collagen and collagen-PDS implants significantly increased the biomechanical properties of the lesions compared to the control tendons at 60DPI (P<0.05). The tissue engineered implants also reduced peritendinous adhesion, muscle fibrosis and atrophy, and increased ultrasonographical echogenicity and homogenicity, maturation and differentiation of the collagen fibrils and fibers, tissue alignment and volume of the regenerated tissue compared to those of the control lesions (P<0.05). The implants were gradually absorbed and substituted by the new tendon. Implantation of the bioimplants had a significant role in initiating tendon healing and the implants were biocompatible, biodegradable and safe for application in tendon reconstructive surgery. The results of the present study may be valuable in clinical practice. PMID:24039851

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

2013-01-01

327

Gap junction protein expression and cellularity: comparison of immature and adult equine digital tendons.  

PubMed

Injury to the energy-storing superficial digital flexor tendon is common in equine athletes and is age-related. Tenocytes in the superficial digital flexor tendon of adult horses appear to have limited ability to respond adaptively to exercise or prevent the accumulation of strain-induced microdamage. It has been suggested that conditioning exercise should be introduced during the growth period, when tenocytes may be more responsive to increased quantities or intensities of mechanical strain. Tenocytes are linked into networks by gap junctions that allow coordination of synthetic activity and facilitate strain-induced collagen synthesis. We hypothesised that there are reductions in cellular expression of the gap junction proteins connexin (Cx) 43 and 32 during maturation and ageing of the superficial digital flexor tendon that do not occur in the non-injury-prone common digital extensor tendon. Cryosections from the superficial digital flexor tendon and common digital extensor tendon of 5 fetuses, 5 foals (1-6 months), 5 young adults (2-7 years) and 5 old horses (18-33 years) were immunofluorescently labelled and quantitative confocal laser microscopy was performed. Expression of Cx43 and Cx32 protein per tenocyte was significantly higher in the fetal group compared with all other age groups in both tendons. The density of tenocytes was found to be highest in immature tissue. Higher levels of cellularity and connexin protein expression in immature tendons are likely to relate to requirements for tissue remodelling and growth. However, if further studies demonstrate that this correlates with greater gap junctional communication efficiency and synthetic responsiveness to mechanical strain in immature compared with adult tendons, it could support the concept of early introduction of controlled exercise as a means of increasing resistance to later injury. PMID:17848160

Stanley, Rachael L; Fleck, Roland A; Becker, David L; Goodship, Allen E; Ralphs, Jim R; Patterson-Kane, Janet C

2007-09-01

328

Lineage Tracing of Resident Tendon Progenitor Cells during Growth and Natural Healing  

PubMed Central

Unlike during embryogenesis, the identity of tissue resident progenitor cells that contribute to postnatal tendon growth and natural healing is poorly characterized. Therefore, we utilized 1) an inducible Cre driven by alpha smooth muscle actin (SMACreERT2), that identifies mesenchymal progenitors, 2) a constitutively active Cre driven by growth and differentiation factor 5 (GDF5Cre), a critical regulator of joint condensation, in combination with 3) an Ai9 Cre reporter to permanently label SMA9 and GDF5-9 populations and their progeny. In growing mice, SMA9+ cells were found in peritendinous structures and scleraxis-positive (ScxGFP+) cells within the tendon midsubstance and myotendinous junction. The progenitors within the tendon midsubstance were transiently labeled as they displayed a 4-fold expansion from day 2 to day 21 but reduced to baseline levels by day 70. SMA9+ cells were not found within tendon entheses or ligaments in the knee, suggesting a different origin. In contrast to the SMA9 population, GDF5-9+ cells extended from the bone through the enthesis and into a portion of the tendon midsubstance. GDF5-9+ cells were also found throughout the length of the ligaments, indicating a significant variation in the progenitors that contribute to tendons and ligaments. Following tendon injury, SMA9+ paratenon cells were the main contributors to the healing response. SMA9+ cells extended over the defect space at 1 week and differentiated into ScxGFP+ cells at 2 weeks, which coincided with increased collagen signal in the paratenon bridge. Thus, SMA9-labeled cells represent a unique progenitor source that contributes to the tendon midsubstance, paratenon, and myotendinous junction during growth and natural healing, while GDF5 progenitors contribute to tendon enthesis and ligament development. Understanding the mechanisms that regulate the expansion and differentiation of these progenitors may prove crucial to improving future repair strategies. PMID:24759953

Dyment, Nathaniel A.; Hagiwara, Yusuke; Matthews, Brya G.; Li, Yingcui; Kalajzic, Ivo; Rowe, David W.

2014-01-01

329

Controlled delivery of mesenchymal stem cells and growth factors using a nanofiber scaffold for tendon repair  

PubMed Central

Outcomes after tendon repair are often unsatisfactory, despite improvements in surgical techniques and rehabilitation methods. Recent studies aimed at enhancing repair have targeted the paucicellular nature of tendon for enhancing repair; however, most approaches for delivering growth factors and cells have not been designed for dense connective tissues such as tendon. Therefore, we developed a scaffold capable of delivering growth factors and cells in a surgically manageable form for tendon repair. The growth factor PDGF-BB along with adipose-derived mesenchymal stem cells (ASCs) was incorporated into a heparin/fibrin-based delivery system (HBDS). This hydrogel was then layered with an electrospun nanofiber poly-lactic-co-glycolic acid (PLGA) backbone. The HBDS allowed for the concurrent delivery of PDGF-BB and ASCs in a controlled manner, while the PLGA backbone provided structural integrity for surgical handling and tendon implantation. In vitro studies verified that the cells remained viable, and that sustained growth factor release was achieved. In vivo studies in a large animal tendon model verified that the approach was clinically relevant, and that the cells remained viable in the tendon repair environment. Only a mild immunoresponse was seen at dissection, histologically, and at the mRNA level; fluorescently-labeled ASCs and the scaffold were found at the repair site 9 days postoperatively; and increased total DNA was observed in ASC-treated tendons. The novel layered scaffold has the potential for improving tendon healing due to its ability to deliver both cells and growth factors simultaneously in a surgically convenient manner. PMID:23416576

Manning, CN; Schwartz, AG; Liu, W; Xie, J; Havlioglu, N; Sakiyama-Elbert, SE; Silva, MJ; Xia, Y; Gelberman, RH; Thomopoulos, S

2013-01-01

330

Influence of aerobic cycle exercise training on patellar tendon cross-sectional area in older women.  

PubMed

Nine to 12 weeks of resistance exercise training in young individuals induces quadriceps muscle (?6%) and region-specific patellar tendon (4-6%) hypertrophy. However, 12 weeks of resistance exercise training (?1?h total exercise time) in older individuals (60-78 years) induces quadriceps muscle hypertrophy (9%) without impacting patellar tendon size. The current study examined if a different loading paradigm using cycle exercise would promote patellar tendon hypertrophy or alter the internal tendon properties, measured with magnetic resonance imaging signal intensity, in older individuals. Nine women (70?±?2 years) completed 12 weeks of aerobic upright cycle exercise training (?28?h total exercise time). Aerobic exercise training increased (P?tendon cross-sectional area (CSA) (2?±?1%) and signal intensity (-1?±?2%) were unchanged (P?>?0.05) over the 12 weeks of training. Region-specific CSA was unchanged (P?>?0.05) at the proximal (-1?±?3%) and mid regions (2?±?2%) of the tendon but tended (P?=?0.069) to increase at the distal region (5?±?3%). Region-specific signal intensity differed along the tendon but was unchanged (P?>?0.05) with training. Although more studies are needed, exercise-induced patellar tendon hypertrophy, compared with skeletal muscle, appears to be attenuated in older individuals, while the loading pattern associated with aerobic exercise seems to have more impact than resistance exercise in promoting patellar tendon hypertrophy. PMID:22092782

Standley, R A; Harber, M P; Lee, J D; Konopka, A R; Trappe, S W; Trappe, T A

2013-06-01

331

The effect of muscle loading on flexor tendon-to-bone healing in a canine model.  

PubMed

Previous tendon and ligament studies have demonstrated a role for mechanical loading in tissue homeostasis and healing. In uninjured musculoskeletal tissues, increased loading leads to an increase in mechanical properties, whereas decreased loading leads to a decrease in mechanical properties. The role of loading on healing tissues is less clear. We studied tendon-to-bone healing in a canine flexor tendon-to-bone injury and repair model. To examine the effect of muscle loading on tendon-to-bone healing, repaired tendons were either cut proximally (unloaded group) to remove all load from the distal phalanx repair site or left intact proximally (loaded group). All paws were casted postoperatively and subjected to daily passive motion rehabilitation. Specimens were tested to determine functional properties, biomechanical properties, repair-site gapping, and bone mineral density. Loading across the repair site led to improved functional and biomechanical properties (e.g., stiffness for the loaded group was 8.2 +/- 3.9 versus 5.1 +/- 2.5 N/mm for the unloaded group). Loading did not affect bone mineral density or gapping. The formation of a gap between the healing tendon and bone correlated with failure properties. Using a clinically relevant model of flexor tendon injury and repair, we found that muscle loading was beneficial to healing. Complete removal of load by proximal transection resulted in tendon-to-bone repairs with less range of motion and lower biomechanical properties compared to repairs in which the muscle-tendon-bone unit was left intact. PMID:18524009

Thomopoulos, Stavros; Zampiakis, Emmanouil; Das, Rosalina; Silva, Matthew J; Gelberman, Richard H

2008-12-01

332

Is echogenicity a viable metric for evaluating tendon properties in vivo?  

PubMed

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

Suydam, Stephen M; Buchanan, Thomas S

2014-06-01

333

Sustained Release of Amnion-Derived Cellular Cytokine Solution Facilitates Achilles Tendon Healing in Rats  

PubMed Central

Objective: In the United States, around 50% of all musculoskeletal injuries are soft tissue injuries including ligaments and tendons. The objective of this study is to assess the role of amnion-derived cellular cytokine solution (ACCS) in carboxy-methyl cellulose (CMC) gel in the healing of Achilles tendon in a rat model, and to examine its effects on mechanical properties and collagen content. Methods: Achilles tendons of Sprague-Dawley rats were exposed and transected. The distal and proximal ends were injected with either saline or ACCS in CMC, in a standardized fashion, and then sutured using a Kessler technique. Tendons from both groups were collected at 1, 2, 4, 6, and 8 weeks postoperatively and assessed for material properties. Collagen studies were performed, including collagen content, collagen cross-linking, tendon hydration, and immunohistochemistry. Tendons were also evaluated histologically for cross-sectional area. Results: Mechanical testing demonstrated that treatment with ACCS in CMC significantly enhances breaking strength, ultimate tensile strength, yield strength, and Young's modulus in the tendon repair at early time points. In context, collagen content, as well as collagen cross-linking, was also significantly affected by the treatment. Conclusion: The application of ACCS in CMC has a positive effect on healing tendons by improving mechanical properties at early time points. Previous studies on onetime application of ACCS (not in CMC) did not show significant improvement on tendon healing at any time point. Therefore, the delivery in a slow release media like CMC seems to be essential for the effects of ACCS demonstrated in this study. PMID:25210571

Kueckelhaus, Maximilian; Philip, Justin; Kamel, Rami A.; Canseco, Jose A.; Hackl, Florian; Kiwanuka, Elizabeth; Kim, Mi J.; Wilkie, Ryan; Caterson, Edward J.; Junker, Johan P. E.

2014-01-01

334

Controlled delivery of mesenchymal stem cells and growth factors using a nanofiber scaffold for tendon repair.  

PubMed

Outcomes after tendon repair are often unsatisfactory, despite improvements in surgical techniques and rehabilitation methods. Recent studies aimed at enhancing repair have targeted the paucicellular nature of tendon for enhancing repair; however, most approaches for delivering growth factors and cells have not been designed for dense connective tissues such as tendon. Therefore, we developed a scaffold capable of delivering growth factors and cells in a surgically manageable form for tendon repair. Platelet-derived growth factor BB (PDGF-BB), along with adipose-derived mesenchymal stem cells (ASCs), were incorporated into a heparin/fibrin-based delivery system (HBDS). This hydrogel was then layered with an electrospun nanofiber poly(lactic-co-glycolic acid) (PLGA) backbone. The HBDS allowed for the concurrent delivery of PDGF-BB and ASCs in a controlled manner, while the PLGA backbone provided structural integrity for surgical handling and tendon implantation. In vitro studies verified that the cells remained viable, and that sustained growth factor release was achieved. In vivo studies in a large animal tendon model verified that the approach was clinically relevant, and that the cells remained viable in the tendon repair environment. Only a mild immunoresponse was seen at dissection, histologically, and at the mRNA level; fluorescently labeled ASCs and the scaffold were found at the repair site 9days post-operatively; and increased total DNA was observed in ASC-treated tendons. The novel layered scaffold has the potential for improving tendon healing due to its ability to deliver both cells and growth factors simultaneously in a surgically convenient manner. PMID:23416576

Manning, C N; Schwartz, A G; Liu, W; Xie, J; Havlioglu, N; Sakiyama-Elbert, S E; Silva, M J; Xia, Y; Gelberman, R H; Thomopoulos, S

2013-06-01

335

Fetal tendon wound size modulates wound gene expression and subsequent wound phenotype.  

PubMed

The fetal response to small tendon injury results in regenerative or scarless healing and is characterized by a markedly diminished cellular inflammatory response, lack of fibroplasia, and restoration of normal tissue architecture. We hypothesized that an increasing fetal tendon wound size would lead to increased wound inflammation and a change from regenerative to reparative healing and scar formation. We created small or large tendon wounds in early gestation fetal sheep and used histology to assess tissue architecture, immunohistochemistry to assess the cellular inflammatory response, ovine-specific gene microarrays, and real-time reverse transcription-polymerase chain reaction to measure the gene expression in response to injury. Small tendon wounds showed a regenerative healing phenotype with orderly deposition of collagen fibers while large tendon wounds showed disorderly collagen deposition consistent with scar formation. Small tendon wounds had few inflammatory cells at 7 and 28 days after injury, whereas the large wounds showed a significant inflammatory cell infiltrate at 7 days that resolved by 28 days. At 3 days, the differential expression of genes involved in the response to injury and inflammation were seen between large and small tendon wounds. By real-time polymerase chain reaction at 7 days, large tendon wounds also had significantly increased expression of interleukin-6, interleukin-8, transforming growth factor-?1, and transforming growth factor-?3, compared with the small wounds. Increasing the fetal tendon wound size results in increased proinflammatory gene expression, inflammatory cell infiltration, and a change from regenerative to reparative healing. This model allows the process of regenerative healing to be examined without the confounding variable of gestational age. PMID:20840524

Herdrich, Benjamin J; Danzer, Enrico; Davey, Marcus G; Bermudez, Dustin M; Radu, Antoneta; Zhang, Liping; Zhang, Zhe; Soslowsky, Louis J; Liechty, Kenneth W

2010-01-01

336

The Effects of Mechanical Loading on Tendons - An In Vivo and In Vitro Model Study  

PubMed Central

Mechanical loading constantly acts on tendons, and a better understanding of its effects on the tendons is essential to gain more insights into tendon patho-physiology. This study aims to investigate tendon mechanobiological responses through the use of mouse treadmill running as an in vivo model and mechanical stretching of tendon cells as an in vitro model. In the in vivo study, mice underwent moderate treadmill running (MTR) and intensive treadmill running (ITR) regimens. Treadmill running elevated the expression of mechanical growth factors (MGF) and enhanced the proliferative potential of tendon stem cells (TSCs) in both patellar and Achilles tendons. In both tendons, MTR upregulated tenocyte-related genes: collagen type I (Coll. I ?10 fold) and tenomodulin (?3–4 fold), but did not affect non-tenocyte-related genes: LPL (adipocyte), Sox9 (chondrocyte), Runx2 and Osterix (both osteocyte). However, ITR upregulated both tenocyte (Coll. I ?7–11 fold; tenomodulin ?4–5 fold) and non-tenocyte-related genes (?3–8 fold). In the in vitro study, TSCs and tenocytes were stretched to 4% and 8% using a custom made mechanical loading system. Low mechanical stretching (4%) of TSCs from both patellar and Achilles tendons increased the expression of only the tenocyte-related genes (Coll. I ?5–6 fold; tenomodulin ?6–13 fold), but high mechanical stretching (8%) increased the expression of both tenocyte (Coll. I ?28–50 fold; tenomodulin ?14–48 fold) and non-tenocyte-related genes (2–5-fold). However, in tenocytes, non-tenocyte related gene expression was not altered by the application of either low or high mechanical stretching. These findings indicate that appropriate mechanical loading could be beneficial to tendons because of their potential to induce anabolic changes in tendon cells. However, while excessive mechanical loading caused anabolic changes in tendons, it also induced differentiation of TSCs into non-tenocytes, which may lead to the development of degenerative tendinopathy frequently seen in clinical settings. PMID:23977130

Zhang, Jianying; Wang, James H-C.

2013-01-01

337

Concept development of a tendon arm manipulator and anthropomorphic robotic hand  

NASA Technical Reports Server (NTRS)

AMETEK/ORED inhouse research and development efforts leading toward a next-generation robotic manipulator arm and end-effector technology is summarized. Manipulator arm development has been directed toward a multiple-degree-of-freedom, flexible, tendon-driven concept referred to here as a Tendon Arm Manipulator (TAM). End-effector development has been directed toward a three-fingered, dextrous, tendon-driven, anthropomorphic configuration which is referred to as an Anthropomorphic Robotic Hand (ARH). Key technology issues are identified for both concepts.

Tolman, C. T.

1987-01-01

338

Imaging the noncentrosymmetric structural organization of tendon with Interferometric Second Harmonic Generation microscopy.  

PubMed

We report the imaging of tendon with Interferometric Second Harmonic Generation microscopy. We observe that the noncentrosymmetric structural organization can be maintained along the fibrillar axis over more than 150 ?m, while in the transverse direction it is ?1-15 ?m. Those results are explained by modeling tendon as a heterogeneous distribution of noncentrosymmetric nano-cylinders (collagen fibrils) oriented along the fibrillar axis. The preservation of the noncentrosymmetric structural organization over multiple tens of microns reveals that tendon is made of domains in which the ratio between fibrils with positive and negative polarity is unbalanced. PMID:23894135

Rivard, Maxime; Popov, Konstantin; Couture, Charles-André; Laliberté, Mathieu; Bertrand-Grenier, Antony; Martin, François; Pépin, Henri; Pfeffer, Christian P; Brown, Cameron; Ramunno, Lora; Légaré, François

2014-08-01

339

Cellular response and extracellular matrix breakdown in rotator cuff tendon rupture  

Microsoft Academic Search

Purpose  The aim of this study was to investigate the relationship between the disruption of ECM and cellular events including autophagic\\u000a cell death, apoptosis and cell differentiation into myofibroblasts in the degenerative rotator cuff tendon.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Tendon samples were collected from 30 patients undergoing surgery for rotator cuff tears. Apoptosis, autophagic cell death\\u000a and myofibroblasts of the tendon cells in the ruptured

Bing Wu; Jimin Chen; Tammyl Dela Rosa; Qian Yu; Allan Wang; Jiake Xu; Ming-Hao Zheng

2011-01-01

340

Peroneal tendon tears, surgical management and its complications.  

PubMed

Peroneal tendon injuries in the athlete are recognized with increasing frequency as a pathologic entity. Once considered uncommon, they have been attributed to many cases of persistent lateral ankle symptoms after a "typical" ankle sprain. Acute tears of the peroneus brevis, and less commonly the peroneus longus, have been implicated in sport activities and are often coexistent with peroneal instability. Subluxation typically occurs when the foot is in a dorsiflexed position and the peroneal muscles strongly contract, causing an eversion force simultaneously. Peroneal instability, as well as tearing, has been linked to ballet dancing, skiing, soccer, tennis, American football, running, basketball, and ice skating. This article discusses the mechanism of injury, methods of patient evaluation and management, complications, and outcomes. PMID:19501808

Cerrato, Rebecca A; Myerson, Mark S

2009-06-01

341

Low-power-laser therapy used in tendon damage  

NASA Astrophysics Data System (ADS)

The following paper covers evaluation of low-power laser therapy results in chronic Achilles tendon damage and external Epicondylalia (tennis elbow). Fifty patients with Achilles damage (18 women and 32 men, age average 30, 24 plus or minus 10, 39 years) and fifty patients having external Epicondyalgiae (31 women and 19 men, age average 44, 36 plus or minus 10, 88 years) have been examined. The patients were irradiated by semiconductor infrared laser wavelength 904 nm separately or together with helium-neon laser wavelength 632.8 nm. The results of therapy have been based on the patient's interviews and examinations of patients as well as on the Laitinen pain questionnaire. The results prove analgesic effects in usage of low- power laser radiation therapy can be obtained.

Strupinska, Ewa

1996-03-01

342

Grip lock injury resulting in extensor tendon pseudorupture: case report.  

PubMed

Grip lock injuries are uncommon, potentially devastating occurrences in male gymnasts performing high bar routines, and typically cause severe wrist sprains or forearm fractures. We retrospectively reviewed medical records of a 24-year-old former collegiate gymnast surgically treated for complete loss of index and long finger extension (pseudorupture) after a grip lock injury. Intraoperative evaluation 3 weeks after injury revealed profound intratendinous attenuation of index and long finger extensors with adhesions in the fourth compartment. We performed tenolysis and imbrication of the affected tendons. At 12-month follow-up, the patient had no pain, full digital range of motion with the wrist in neutral, but residual extensor lag with the wrist in extension. He had returned to gymnastics with some apprehension. This case broadens the known spectrum of grip lock injuries. PMID:24161473

Sathyendra, Vikram; Payatakes, Alexander

2013-12-01

343

Early active motion flexor tendon protocol using one splint.  

PubMed

This article describes an early active motion protocol for use after a four-strand flexor tendon repair. The protocol uses a simple dorsal blocking splint with the wrist in neutral and four fingers in rubber band traction for the first five weeks, then gradually advances the patient over the next seven weeks. The patient is able to perform the exercises without changing the splint at home during the first five weeks of the protocol. The results of the retrospective chart review are promising. Of 40 digits, 95% experienced excellent and good results in zone II, and 87.5% experienced excellent and good results in zones I, II, and III. One rupture (2.5%) occurred in a noncompliant patient. The DASH scale was used to determine functional outcome, with results of 7.82 on the physical function/symptoms category, 16.07 in sports/ performing arts, and 10.23 in the work category. PMID:12943122

Klein, Linda

2003-01-01

344

Local NO synthase inhibition produces histological and functional recovery in Achilles tendon of rats after tenotomy: tendon repair and local NOS inhibition.  

PubMed

Repair of injured tendon is a very slow process and involves the release of many molecules, including nitric oxide. We investigate the influence of local nitrergic inhibition in histological and functional recovery of injured Achilles tendon. A standard murine model of tendon injury by rupture was used. The animals were divided into three experimental groups: control, injury + vehicle (normal saline) and injury + N?-nitro-L-arginine methyl ester (L-NAME). The products were injected into the paratendinous region every 2 days and body weight gain and Achilles functional index (AFI) were evaluated on days 0, 7, 14 and 21 after tendon injury. On day 21 post-injury, the animals were killed to evaluate nitric oxide production and tissue organization. We observed that tendon surgical division led to increased tissue nitrite levels, which were reduced in L-NAME-treated rats. The AFI revealed functional recovery of L-NAME-treated animals on day 21 post-injury, which was not observed in the saline-treated group. Microscopic analysis of hematoxylin-eosin staining and collagen autofluorescence showed that L-NAME-treated rats had more aligned areas of collagen fibers and that the diameter of newly organized collagen in this group was also greater than that in the vehicle-treated one. We demonstrate that local treatment with L-NAME significantly improves the functional parameters and accelerates histomorphological recovery. PMID:23839241

Moraes, Suellen A S; Oliveira, Karen R M; Crespo-López, Maria E; Picanço-Diniz, Domingos L W; Herculano, Anderson M

2013-09-01

345

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

PubMed Central

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

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

2011-01-01

346

SYMPOSIUM: NEW APPROACHES TO ALLOGRAFT TRANSPLANTATION Mechanoactive Scaffold Induces Tendon Remodeling  

E-print Network

,000 injuries reported [20] and more than 100,000 ACL reconstruction procedures performed annually [2-bone (BPTB) grafts, with a shift in recent years toward the semitendi- nosus or hamstring tendon grafts [19

Lu, Helen H.

347

Sonographic evaluation of the distal iliopsoas tendon using a new approach.  

PubMed

Sonography of the iliopsoas tendon plays an important role in the diagnosis and preoperative and postoperative management for the increasing number of patients under consideration for arthroscopically guided hip interventions such as iliopsoas tenotomy in a variety of conditions, including arthropathy, periarticular calcifications, and cam-type deformities of the femoral head. The ability to visualize the iliopsoas tendon pre-operatively can be helpful diagnostically in patients presenting with hip pain and can aid in planning surgery, while evaluating the tendon postoperatively is important in the assessment of causes of postoperative pain and other potential complications. We present a novel technique for visualizing the distal iliopsoas tendon complex in the longitudinal axis at its insertion on the lesser trochanter on sonography. PMID:25336491

Balius, Ramon; Pedret, Carles; Blasi, Marc; Miguel, Maribel; Vallejo, Beatriz; Margalet, Eric; Bong, David A; Martinoli, Carlo

2014-11-01

348

Biologic augmentation of tendon-to-bone healing: scaffolds, mechanical load, vitamin D, and diabetes.  

PubMed

Biologic and synthetic scaffolds, mechanical loads, vitamin D, and diabetes can affect tendon and tendon-to-bone healing, muscle recovery, and growth in the perioperative period. Despite important advances in technical approaches to achieve surgical repair of soft tissues in a minimally invasive fashion, structural healing after tendon-to-bone repair remains a formidable challenge that is complicated by our incomplete knowledge of complex natural biologic processes and a diverse patient population with various comorbidities and deficiencies. Scientific research has led to promising strategies for promoting a structural repair that recapitulates the native anatomy of the tendon or enthesis. Augmentation with scaffolds may reinforce the initial repair biomechanically and can be coupled with growth factors to promote a favorable biologic environment for healing. Careful consideration of the implications of postoperative rehabilitation and endocrine and nutritional deficiencies on structural healing and muscle recovery are also critical to optimize patient outcomes. PMID:24720330

Nossov, Sarah; Dines, Joshua S; Murrell, George A C; Rodeo, Scott A; Bedi, Asheesh

2014-01-01

349

An Unusual Knee Trauma: Combined Rupture of Medial Collateral Ligament and Patellar Tendon  

PubMed Central

We present the case of a combined lesion of the medial collateral ligament (MCL) and patellar tendon of the knee in a 45-year-old man, after a fall while skiing. Although there are numerous publications concerning associated tears of MCL and other knee ligaments, a combination of MCL tear with a rupture of the patellar tendon is very rare. After a review of the literature and treatment guidelines about these lesions, the clinical case is described and discussed. This knee trauma was treated with a transosseous reinsertion of the patellar tendon, which was reinforced by an allograft of fascia lata, followed by a direct suture of the MCL, which was reinforced with the lateral semitendinosus tendon. PMID:25202463

De Baere, T.; De Muylder, J.; Deltour, A.

2014-01-01

350

Fatal Pulmonary Embolism following Achilles Tendon Repair: A Case Report and a Review of the Literature  

PubMed Central

Deep venous thrombosis (DVT) is a significant source of morbidity in orthopaedic surgery. It can progress to a pulmonary embolism, a significant source of mortality. Up to date, patients with Achilles tendon rupture routinely do not receive DVT chemical prophylaxis. We are presenting a case of fatal pulmonary embolism after a surgically treated Achilles tendon rupture in a forty-two-year-old male healthy patient. In the current body of the literature, the reported incidence of DVT after Achilles tendon rupture is highly variable ranging from less than 1% to 34%, and there is a disagreement in the international guidelines regarding the need of chemical DVT prophylaxis with this type of injury. Further research needs to be conducted to investigate the risks and benefits of chemical DVT prophylaxis following Achilles tendon rupture. For low-risk patients, the use of milder forms of prophylaxis such as aspirin should also be explored. PMID:23819088

Makhdom, Asim M.; Dimentberg, Ronald

2013-01-01

351

A review on the use of cell therapy in the treatment of tendon disease and injuries  

PubMed Central

Tendon disease and injuries carry significant morbidity worldwide in both athletic and non-athletic populations. It is estimated that tendon injuries account for 30%?50% of all musculoskeletal injuries globally. Current treatments have been inadequate in providing an accelerated process of repair resulting in high relapse rates. Modern concepts in tissue engineering and regenerative medicine have led to increasing interest in the application of cell therapy for the treatment of tendon disease. This review will explore the use of cell therapy, by bringing together up-to-date evidence from in vivo human and animal studies, and discuss the issues surrounding the safety and efficacy of its use in the treatment of tendon disease. PMID:25383170

Sawadkar, Prasad; Mudera, Vivek

2014-01-01

352

Successful recellularization of human tendon scaffolds using adipose-derived mesenchymal stem cells and collagen gel.  

PubMed

The major goal of regenerative medicine is to determine experimental techniques that take maximal advantage of reparative processes that occur naturally in the animal body. Injection of mesenchymal stem cells into the core of a damaged tendon represents such an approach. Decellularization of native tendons as potential targets and seeding protocols are currently under investigation. The aim of our study was to manufacture a recellularized biocompatible scaffold from cadaveric tissue for use in total or partial tendon injuries. Results showed that it was possible to introduce proliferating cells into the core of a decellularized tendon to treat the scaffold with a collagen gel. The method was effective in maintaining scaffold extracellular matrix and for expressing collagen type I and cartilage oligomeric matrix protein by injecting mesenchymal stem cells. PMID:22711488

Martinello, Tiziana; Bronzini, Ilaria; Volpin, Andrea; Vindigni, Vincenzo; Maccatrozzo, Lisa; Caporale, Giovanni; Bassetto, Franco; Patruno, Marco

2014-08-01

353

Closed complete rupture of the flexor hallucis longus tendon at the groove of the talus.  

PubMed

A rare case of closed complete rupture of the flexor hallucis longus tendon at its groove in the posterior process of the talus is reported in a soccer player who developed pseudarthrosis of the posterolateral tubercle of the talus after a Shepherd's fracture. Partial rupture or tenosynovitis of the flexor hallucis longus tendon at this level is well known in classical ballet dancers and soccer players. Three cases of complete rupture of the flexor hallucis longus tendon near the metatarsophalangeal joint and three under the sustentaculum tali have been reported, but there have been no reports at the groove of the talus. Repair was accomplished by tendon graft, and active flexion of the interphalangeal joint is now possible. PMID:9013115

Inokuchi, S; Usami, N

1997-01-01

354

Validation and Practical Procedure for Vibrational Evaluation of Tendons, Final Report.  

National Technical Information Service (NTIS)

Vibrational testing of tension to identify potentially distressed external tendons of post-tensioned segments and column has been successfully used in major FDOT bridges. The investigation provided validation of basic assumptions and verification of tensi...

A. A. Sagues, C. Cotrim, J. Lopez-Sabando, T. Eason

2008-01-01

355

Validation and Practical Procedure for Vibrational Evaluation of Tendons, Summary Report.  

National Technical Information Service (NTIS)

For the study, the researchers conducted laboratory vibrational tests on tendon samples. They also instrumented the samples with load cells to obtain independent measurements. The vibrational test results agreed closely with the load cell measurements, th...

2008-01-01

356

Nanostructured substrate fabricated by sectioning tendon using a microtome for tissue engineering  

NASA Astrophysics Data System (ADS)

This paper describes an efficient and versatile method for the fabrication of nanostructured substrates from a piece of tendon which comprises aligned collagen nanofibers. We used a microtome to generate the tendon slices (10-50 µm thick), which were used as a scaffold for guiding directional cell growth. Highly aligned and uniform monolayer cells sheets were obtained. The tendon slices were used as a master, and the nanostructures outlined by the bundles of collagen nanofibers were successfully transferred onto a polystyrene film using standard soft lithography. The cell growing on the nanostructured polystyrene substrate showed good adhesion and alignment. The technique developed here enables one to fabricate nanostructured substrates without using any traditional micro/nanofabrication tools. The nanostructured substrate, e.g. a slice of tendon, has excellent biocompatibility and relatively good mechanical stability, which makes this technique useful in constructing complicated 3D tissues.

Dai, Xiaoshu; Xu, Qiaobing

2011-12-01

357

Unrecognized pediatric partial achilles tendon injury followed by traumatic completion: a case report and literature review.  

PubMed

Achilles tendon ruptures are a relatively common athletic injury but are exceedingly rare in the pediatric population. We describe the case of a 10-year-old ice hockey player who experienced an Achilles tendon injury from a laceration to the posterior leg from a skate blade that led to a partial tendon laceration. This tendon injury was initially unrecognized despite an emergency department evaluation. The patient continued to complain of weakness and paresthesia after the skin laceration had healed. A traumatic dorsiflexion injury while running several weeks later led to a traumatic complete tendon rupture. The clinical, operative, and physical therapy records were reviewed to complete the history, treatment, and rehabilitation progress. The initial laceration injury had occurred 6 weeks before presentation, and the traumatic dorsiflexion injury had occurred 2 days before referral to an acute orthopedics clinic. Open repair was performed several days after the traumatic completion of the laceration, and the patient was immobilized in a cast for 5 weeks. The patient had weaned off crutches by 10 weeks postoperatively and had returned to some activities and light skating at 5.5 months. A full return to running and ice hockey had been achieved by 8 months postoperatively. The optimal repair for this injury has not been well established in published studies. We have concluded that laceration injuries have the potential to mask tendon injuries and that prolonged symptoms after a laceration should suggest occult pathologic features. Open tendon repair is a viable treatment option in the pediatric patient with Achilles tendon ruptures. A return to activities within a reasonable period can be expected with robust physical therapy. PMID:24713492

Vasileff, William Kelton; Moutzouros, Vasilios

2014-01-01

358

The effect of enrofloxacin on cell proliferation and proteoglycans in horse tendon cells  

Microsoft Academic Search

Fluoroquinolone antibiotics have been used widely in humans and domestic animals, including horses, because of their broad-spectrum\\u000a bactericidal activity, and relative safety. The use of fluoroquinolones, however, is not without risk. Tendonitis and spontaneous\\u000a tendon rupture have been reported in people during or following therapy with fluoroquinolones. We have studied the effects\\u000a of enrofloxacin, a fluoroquinolone antibiotic used commonly in

J. H. Yoon; R. L. Brooks Jr.; A. Khan; H. Pan; J. Bryan; J. Zhang; S. C. Budsberg; P. O. E. Mueller; J. Halper

2004-01-01

359

Acute tibialis posterior tendon rupture associated with a distal tibial fracture.  

PubMed

Tibialis posterior tendon ruptures associated with closed medial malleolar fractures are rare. This article describes the association of tibialis posterior tendon ruptures with closed, high-energy, distal tibia fractures. Tendon ruptures are likely to be identified intraoperatively or missed if clinical evaluation at acute injury is limited. A high index of suspicion is required to diagnose this injury. The consequences of an unrecognized tibialis posterior tendon rupture include progressive, painful pes planus deformities due to the unopposed action of the peroneus brevis muscle and lack of support of the medial longitudinal arch. Secondary operative intervention may be required. This article describes an intraoperative tenodesis technique between the tibialis posterior and flexor digitorum longus tendons when direct repair is not possible.A 48-year-old woman sustained a closed AO/Orthopaedic Trauma Association type 43A right lower-extremity distal tibia fracture and a traumatic left knee arthrotomy. Temporary stabilization with an external fixator was performed, followed by open reduction and internal fixation of the distal tibial fracture 6 days later. A periarticular nonlocking medial plate was applied, and the tibialis posterior tendon was shortened. We performed a direct tenodesis to the flexor digitorum longus tendon. At 1-year follow-up, the patient had made excellent progress, with no detectable muscle weakness, and was able to perform a single-leg toe raise.A review of the literature suggested which features of radiological evidence of tendon rupture should be examined, which may be useful in the current era considering most high-energy distal tibia or pilon fractures undergo examination with computed tomography. PMID:22495868

Jarvis, Hannah C; Cannada, Lisa K

2012-04-01

360

A proteomic analysis of engineered tendon formation under dynamic mechanical loading in vitro.  

PubMed

Previous studies have demonstrated the beneficial effect of mechanical loading on in vitro tendon engineering. To understand the mechanism, human tenocytes and polyglycolic acid long fibers were used for in vitro tendon engineering in a bioreactor system for 12 weeks with and without dynamic loading. The engineered neo-tendons were subjected to proteomic analysis using mass spectrometry along with shotgun strategy. As expected, mechanical loading resulted in a more mature tendon tissue characterized by a firmer tissue texture and densely deposited matrices which formed longitudinally aligned collagen fibers in a highly compact fashion. In contrast, non-loaded neo-tendon revealed loosely and less deposited matrices in a relatively less organized pattern. Proteins isolated from two groups of tissues exhibited similar distribution of isoeletric point and molecular weight indicating the similarity and comparability of the tissue specimens. Further, proteomic analysis showed that total 758 proteins were identified from both groups with 194 and 177 proteins uniquely presented in loaded and non-loaded tendons, respectively. Comparison of loaded and non-loaded tendons revealed 195 significantly up-regulated proteins and 189 significantly down-regulated proteins. The differentially expressed proteins could generally be classified into the categories of extracellular matrix, intra-cellular signaling, cytoskeleton and inflammatory response. Among them, significantly up-regulated collagens I and VI, MMP-14, WNT5A, microfilament molecules and some inflammatory factors suggest that the possible mechanism for this particular biological phenomenon may involve increased production of tendon specific matrices, enhanced cross-link of collagens and other matrix molecules, proper matrix remodeling for tissue maturation and mechanotransduction (including non-canonical Wnt signal pathway) mediated other biological processes. PMID:21402406

Jiang, Yongkang; Liu, Hongwei; Li, Hong; Wang, Fangjun; Cheng, Kai; Zhou, Guangdong; Zhang, Wenjie; Ye, Mingliang; Cao, Yinlin; Liu, Wei; Zou, Hanfa

2011-06-01

361

Regionspecific differences in Achilles tendon cross-sectional area in runners and non-runners  

Microsoft Academic Search

The present study examined the cross-sectional area (CSA) of the Achilles tendon in subjects who repeatedly exposed their tendons to large loads (habitual runners) compared to control subjects (non-runners). Six male habitual runners [36 (7) years, 70.9 (4.4) kg and 1.84 (0.05) m, ±SD] who had performed distance running (~80 km per week) for the last 5 years were compared to six non-runners [34 (3) years,

S. Peter Magnusson; Michael Kjaer

2003-01-01

362

The relationship of trigger finger and flexor tendon volar migration after carpal tunnel release.  

PubMed

It has been suggested that the increased frequency of trigger finger (TF) after carpal tunnel release (CTR) may be caused by the volar migration of the flexor tendons at the wrist altering the tendon biomechanics at the A1 pulley. This hypothesis has not been validated. We performed pre- and post-operative ultrasonography (USG) on the affected wrists of 92 patients who underwent CTR. Pre-operative USG was performed in neutral with no tendon loading; post-operative USG was performed in neutral unloaded and in various positions of wrist flexion whilst loading the flexor tendons with gripping. The mean volar migration of the flexor tendons after CTR was 2.2 (SD 0.4) mm in the unloaded neutral position. It was 1.8 (SD 0.4) mm in patients who did not develop TF and 2.5 (SD 0.5) mm in those who did (p = 0.0067). In loaded wrist flexion, the mean volar migration of flexor tendons after CTR in patients who did not develop TF and those who did was 2.1 and 3.0 mm in 0° flexion; 3.2 and 3.9 mm in 15° flexion; 4.3 and 5.1 mm in 30° flexion; and 4.9 and 5.8 mm in 45° flexion, respectively. There were significant differences between patients with and without TF at each flexion angle. Our data indicate that patients with greater volar migration of the flexor tendons after CTR are more likely to develop TF. This conclusion supports the hypothesis that the occurrence of TF after CTR may be caused by the bowstringing effects of the flexor tendons. PMID:23442341

Lee, S K; Bae, K W; Choy, W S

2014-09-01

363

Photodiode Camera Measurement of Surface Strains on Tendons during Multiple Cyclic Tests  

Microsoft Academic Search

The objectives of this study are to introduce the use of a photodiode camera for measuring surface strain on soft tissue and to present some representative responses of the tendon. Tendon specimens were obtained from the hindlimbs of canines and frozen to -70°C. After thawing, specimens were mounted in the immersion bath at a room temperature (22°C), preloaded to 0.13N

Keyoung Jin Chun; Robert Philip Hubbard

2006-01-01

364

Mechanical properties of radiation-sterilised human Bone-Tendon-Bone grafts preserved by different methods  

Microsoft Academic Search

Patellar tendon auto- and allo-grafts are commonly used in orthopedic surgery for reconstruction of the anterior cruciate\\u000a ligaments (ACL). Autografts are mainly used for primary reconstruction, while allografts are useful for revision surgery.\\u000a To avoid the risk of infectious disease transmission allografts should be radiation-sterilised. As radiation-sterilisation\\u000a supposedly decreases the mechanical strength of tendon it is important to establish methods

A. Kami?ski; G. Gut; J. Marowska; M. ?ada-Koz?owska; W. Biwejnis; M. Zasacka

2009-01-01

365

The Effects of Common Anti-Inflammatory Drugs on the Healing Rat Patellar Tendon  

Microsoft Academic Search

Background: Tendon injuries that occur at the osteotendinous junction are commonly seen in clinical practice and range from acute strain to rupture. Nonsteroidal anti-inflammatory drugs are often prescribed in the treatment of these conditions, but the effect that these agents may have on the healing response at the bone-tendon junction is unclear.Hypothesis: In response to an acute injury at the

Scott T. Ferry; Laurence E. Dahners; Hessam M. Afshari; Paul S. Weinhold

2007-01-01

366

Biomechanical properties and dry weight content of the developing superficial digital flexor tendon in rabbit  

Microsoft Academic Search

Composition and structural organization of tendon changes during aging and these alterations affect the mechanical behaviors\\u000a of this structure. Therefore, this experiment was designed to study the biomechanical properties together with changes in\\u000a dry weight content of normal superficial digital flexor tendon of rabbits from pre-natal stage to 112 days post-natally. Forty-two\\u000a White New Zealand rabbits were assigned to seven different

A. Oryan; A. H. Shoushtari

2009-01-01

367

Investigation of the validity of modeling the Achilles tendon as having a single insertion site  

Microsoft Academic Search

Objective. To assess the propriety of modeling the Achilles tendon insertion on the calcaneus as a single point when musculoskeletal models are used to predict subtalar joint moment arms.Design. The sensitivity of model-predicted subtalar joint moment arms to insertion site position was investigated and measurements of Achilles tendon function were made in cadaver specimens.Background. The insertion site of the Achilles

Rebecca Avrin Zifchock; Stephen J. Piazza

2004-01-01

368

Paracrine Interactions between Mesenchymal Stem Cells Affect Substrate Driven Differentiation toward Tendon and Bone Phenotypes  

Microsoft Academic Search

We investigated substrate dependent paracrine signaling between subpopulations of bone marrow stromal cells (BMSCs) that may affect the formation, or perhaps malformation, of the regenerating tendon to bone enthesis. Polyacrylamide substrates approximating the elastic modulus of tendon granulation tissue and the osteoid of healing bone (10–90 kPa) were functionalized with whole length fibronectin (Fn), type-I collagen (Col), or a mixed

Ram I. Sharma; Jess G. Snedeker

2012-01-01

369

Investigation of a tissue engineered tendon model by PS-OCT  

NASA Astrophysics Data System (ADS)

A few native tissues, such as tendon, skin and eye, possess highly organized collagenous matrices. In particular, the collagen fibers in tendon are organized into a hierarchical and unidirectional format, which gives rise to the high tissuespecific mechanical properties. This organization has been clearly revealed by a conventional polarized light microscope. The newly developed polarization-sensitive optical coherence tomography (PS-OCT) technique allows non-invasive visualization of birefringence images arising from orientated structures in a three dimensional format. Our previous studies of native tendon and tissue engineered tendon by PS-OCT demonstrate that tissue engineered tendon has a far less perfect collagen fiber organization than native tendon even under dynamic culture conditions. The purpose of this study is to use PS-OCT to assess the relationship between the degree of birefringence, collagen concentration and fiber density in model tendon tissues. The model tissue is constructed from an aligned collagen hydrogel and aligned polyester nanofibers. The effects of the diameter and density of the nanofibers and the collagen concentration in the model have been investigated. The alignment of collagen fibrils is induced by application of a high magnetic field during fibrillogenesis while aligned polyester nanofibers are manufactured using the electrospinning technique. It is found that the collagen concentration, the density and size of nanofiber bundles are the key parameters to produce birefringence in OCT images. The perfectly aligned collagen hydrogel with concentration as high as 4 mg/ml does not exhibit a birefringence image until the hydrogel has been compressed and concentrated. Aligned nanofiber bundles have demonstrated marginal birefringence in the absence of the collagen matrix. These studies enhance our understanding of how to control and optimize the parameters in tendon tissue engineering.

Yang, Ying; Ahearne, Mark; Wimpenny, Ian; Guijarro-Leach, Juan; Torbet, Jim

2010-02-01

370

MRI evaluation of patellar tendon defect after harvesting its central third  

Microsoft Academic Search

Purpose: the purpose of this study was to evaluate defect width of patellar tendon after harvest for anterior cruciate ligament reconstruction. Materials and methods: we performed MRI at various time interval after graft harvest (2–96 months) on 28 patients who had had reconstruction of the anterior cruciate ligament using mid-third patellar tendon. T1 and T2 weighted axial images were obtained

Kutsi Koseoglu; Aysenur Memis; Mehmet Argin; Remide Arkun

2004-01-01

371

The bio-tribological properties of anti-adhesive agents commonly used during tendon repair.  

PubMed

Frictional resistance to tendon gliding is minimized by surrounding loose areolar tissue. During periods of prolonged immobilization, for example, post-tendon-repair, adhesions can form between these two adjacent tissues, thereby limiting tendon function. Anti-adhesive agents can be applied during surgery to prevent adhesion formation, whilst reportedly providing some reduction in friction during in vitro tendon-bony pulley investigations. This bio-tribological study evaluates whether application of these agents can improve the lubrication between the tendon and surrounding tissue, thus potentially reducing the risk of re-rupturing the tendon at the repair site. The use of bovine synovial fluid (BSF) enabled an approximation of the in vivo lubrication regime, and subsequent comparison of the performance of three synthetic agents (50?mg/ml 5-fluorouracil; 5?mg/ml hyaluronic acid; ADCON-T/N). Coefficient of friction data was recorded and then compared with the Stribeck curve. BSF generated a fluid film that separated the two surfaces, giving rise to optimal lubrication conditions. This efficient regime was also generated following application of each anti-adhesion agent. The use of phosphate-buffered saline solution in generating only a boundary lubrication regime highlighted the effectiveness of the agents in reducing friction. Hyaluronic acid (5?mg/ml) was marginally deemed the most effective anti-adhesive agent at lubricating the tendon. Subsequently, it is concluded that the application of anti-adhesive agents post-surgery has secondary, tribological benefits that serve to reduce friction, and thus potentially the risk of failure, at the tendon repair site. PMID:22012635

McGonagle, Lorcan; Jones, Michael D; Dowson, Duncan; Theobald, Peter S

2012-05-01

372

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

Microsoft Academic Search

Dynamic stretching is commonly used in warm-up routines for athletic activities. Even though several positive effects of dynamic stretching on athletic performance have been reported, the effects on the muscle–tendon unit (MTU) itself are still unclear. The objective of this study is to determine the effects of dynamic stretching on the ankle plantar flexor muscle–tendon properties by use of ultrasonography.

Mina Samukawa; Masaki Hattori; Naoko Sugama; Naoki Takeda

2011-01-01

373

An experimental study of low-level laser therapy in rat Achilles tendon injury  

Microsoft Academic Search

The aim of this controlled animal study was to investigate the effect of low-level laser therapy (LLLT) administered 30 min\\u000a after injury to the Achilles tendon. The study animals comprised 16 Sprague Dawley male rats divided in two groups. The right\\u000a Achilles tendons were injured by blunt trauma using a mini guillotine, and were treated with LLLT or placebo LLLT 30 min

Jon Joensen; Nils Roar Gjerdet; Steinar Hummelsund; Vegard Iversen; Rodrigo Alvaro B. Lopes-Martins; Jan Magnus Bjordal

374

Achilles tendon length changes during walking in long-term diabetes patients  

Microsoft Academic Search

BackgroundDiabetes leads to numerous side effects, including an increased density of collagen fibrils and thickening of the Achilles tendon. This may increase tissue stiffness and could affect stretch distribution between muscle and tendinous tissues during walking. The primary aim of this study was to examine stretch distribution between muscle and tendinous tissues in the medial gastrocnemius muscle–tendon unit in long-term

Neil J. Cronin; Jussi Peltonen; Masaki Ishikawa; Paavo V. Komi; Janne Avela; Thomas Sinkjaer; Michael Voigt

2010-01-01

375

Self-monitoring surveillance system for prestressing tendons. Phase I small business innovation research  

SciTech Connect

Assured safety and operational reliability of post-tensioned concrete components of nuclear power plants are of great significance to the public, electric utilities, and regulatory agencies. Prestressing tendons provide principal reinforcement for containment and other structures. In this phase of the research effort, the feasibility of developing a passive surveillance system for identification of ruptures in tendon wires was evaluated and verified. The concept offers high potential for greatly increasing effectiveness of presently-utilized periodic tendon condition surveillance programs. A one-tenth scale ring model of the Palo Verde nuclear containment structure was built inside the Structural Laboratory. Dynamic scaling (similitude) relationships were used to relate measured sensor responses recorded during controlled wire breakages to the expected prototype containment tendon response. Strong and recognizable signatures were detected by the accelerometers used. It was concluded that the unbonded prestressing tendons provide an excellent path for transmission of stress waves resulting from wire breaks. Accelerometers placed directly on the bearing plates at the ends of tendons recorded high-intensity waveforms. Accelerometers placed elsewhere on concrete surfaces of the containment model revealed substantial attenuation and reduced intensities of captured waveforms. Locations of wire breaks could be determined accurately through measurement of differences in arrival times of the signal at the sensors. Pattern recognition systems to be utilized in conjunction with the proposed concept will provide a basis for an integrated and automated tool for identification of wire breaks.

Tabatabai, H.

1995-12-01

376

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

PubMed

Sports participation has undergone an increase in recent decades. Injury due to sporting activity has also recently risen. The Achilles tendon has been one of the most common sports-related injuries. A 2 in 100,000 individual Achilles tendon injury rate increased to a 12 in 100,000 individual injury rate in less than 10 years. The injury is typically observed in men in the fourth to fifth decades of life. Male to female injury ratios range from 2:1 to 12:1. Running, jumping, and agility activities involving eccentric loading and explosive plyometric contractions are usual mechanisms. Natural aging allows predisposing chronic degeneration of the tendon. Blood flow decreases and stiffness increases with aging to decrease the ability to withstand stress. Noninflammatory tendinosis and chronic tendinopathy are 2 separate processes proposed for tendon degeneration and subsequent rupture. Rupture typically occurs 2 to 6 cm proximal to the calcaneal insertion. Predisposing factors are grouped into 2 categories: intrinsic and extrinsic risk factors. Avoidance of degenerative changes within the tendon is the primary method to prevent rupture. Regular physical activity as athletes age also promotes tendon hypertrophy, increases nutrient delivery, and reduces collagen fiber fatigue. PMID:20400437

Hess, Gregory William

2010-02-01

377

Tendon structural adaptations to load exercise are inhibited by anabolic androgenic steroids.  

PubMed

The present study investigated the structural changes in the rat calcaneal tendon (CT), superficial flexor tendon (SFT), and deep flexor tendon (DFT) in response to jump exercises and anabolic androgenic steroids (AAS). Animals were divided into four groups: sedentary, trained, AAS-treated sedentary rats, and AAS-treated trained animals. Training increased the volume density (Vv%) of blood vessels in all regions of the CT and DFT, cell Vv% in the peritendinous sheath of the proximal and distal regions of the SFT and proximal region of DFT, and cell Vv% in the tendon proper of the proximal and distal regions of the SFT and DFT. The combination of AAS and load exercises showed little increased blood vessel Vv% at the proximal region of the CT, intermediate region of the SFT, and all regions of the DFT as opposed to an increase in adipose cell Vv% in the CT proximal region. The AAS reduced the levels of hydroxyproline in the proximal region of the DFT and in the distal region of the STF. In conclusion, exercise promoted benefits to the adaptation of the tendons to overload. These effects were absent when load exercise was combined with AAS. The abusive consumption of AAS contributes to tendon inertness and rigidity, and increases the potential risk of injury. PMID:24224869

Marqueti, R C; Paulino, M G; Fernandes, M N; de Oliveira, E M; Selistre-de-Araujo, H S

2014-02-01

378

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

PubMed Central

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

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

2011-01-01

379

Mechanical and morphological aspects of the calcaneal tendon of mdx mice at 21 days of age.  

PubMed

A relationship between compromised muscles and other tissues has been demonstrated in mdx mouse, an animal model studied for understanding of Duchenne muscular dystrophy. The hypothesis is that changes in the calcaneal tendon of mdx mice occur previous to the onset of rigorous and most marked episodes of muscle degeneration, which start suddenly after 21 days of life. Thus, this study aimed to identify possible alterations in the calcaneal tendon of mdx mouse at 21 days of age. Control and mdx tendons were submitted to mechanical tensile testing, quantification of hydroxyproline, and staining with toluidine blue and picrosirius red. Hydroxyproline content was similar between mdx and control groups. The control tendon presented higher mechanical strength (load, stress, and elastic modulus) and its morphological analysis showed a larger number of round fibroblasts, nuclei with well-decondensed chromatin, and slightly metachromatic well-stained cytoplasmic material, different from that observed in mdx tendons. The results suggest that the absence of dystrophin in mdx mouse can provoke directly or indirectly alterations in the mechanical properties and morphology of the calcaneal tendon. PMID:23934706

Nakagaki, Wilson Romero; Tomiosso, Tatiana Carla; Pimentel, Edson Rosa; Camilli, José Angelo

2013-10-01

380

Extracorporeal shock wave treatment for chronic rotator cuff tendonitis (shoulder pain).  

PubMed

(1) Electrohydraulic, electromagnetic, or piezoelectric devices are used to translate energy into acoustic waves during extracorporeal shock wave treatment (ESWT) for chronic rotator cuff tendonitis (shoulder pain). The acoustic waves may help to accelerate the healing process of chronic rotator cuff tendonitis via an unknown mechanism. (2) ESWT, which is performed as an outpatient procedure, is intended to alleviate the pain due to chronic rotator cuff tendonitis. (3) Limited evidence from a German study indicates that the cost of ESWT for rotator cuff tendonitis is one-fifth to one-seventh the cost of surgical treatment, with longer recovery time and time off work in the surgical treatment group accounting for about two-thirds of the overall cost. (4) The evidence reviewed for this bulletin supports the use of high-energy ESWT for chronic calcific rotator cuff tendonitis, but not for non-calcific rotator cuff tendonitis. High-quality RCTs with larger sample sizes are needed to provide stronger evidence. PMID:17302022

Ho, C

2007-01-01

381

Tissue-engineering strategies for the tendon/ligament-to-bone insertion.  

PubMed

Injuries to connective tissues are painful and disabling and result in costly medical expenses. These injuries often require reattachment of an unmineralized connective tissue to bone. The uninjured tendon/ligament-to-bone insertion (enthesis) is a functionally graded material that exhibits a gradual transition from soft tissue (i.e., tendon or ligament) to hard tissue (i.e., mineralized bone) through a fibrocartilaginous transition region. This transition is believed to facilitate force transmission between the two dissimilar tissues by ameliorating potentially damaging interfacial stress concentrations. The transition region is impaired or lost upon tendon/ligament injury and is not regenerated following surgical repair or natural healing, exposing the tissue to risk of reinjury. The need to regenerate a robust tendon-to-bone insertion has led a number of tissue engineering repair strategies. This review treats the tendon-to-bone insertion site as a tissue structure whose primary role is mechanical and discusses current and emerging strategies for engineering the tendon/ligament-to-bone insertion in this context. The focus lies on strategies for producing mechanical structures that can guide and subsequently sustain a graded tissue structure and the associated cell populations. PMID:22185608

Smith, Lester; Xia, Younan; Galatz, Leesa M; Genin, Guy M; Thomopoulos, Stavros

2012-01-01

382

Thicker Achilles tendons are a risk factor to develop Achilles tendinopathy in elite professional soccer players  

PubMed Central

Summary The primary aim of this prospective cohort study was to compare the incidence of Achilles tendinopathy symptoms in elite soccer players with and without baseline asymptomatic ultrasound abnormalities. This study also investigated the relationship between baseline tendon thickness and development of symptoms. Using ultrasonography, 18 players were examined in 2009 for the existence of hypoechoicity, paratenon blurring, focal thickening and/or neovascularisation, and anteroposterior tendon thickness was measured. Symptom development during the follow-up period was assessed by interview one year later. Baseline mid-tendon thickness was greater (p=0.041) in tendons that experienced symptoms [median (IQR): 0.53 (0.51–0.55) cm] in the following year than tendons remaining asymptomatic [0.48 (0.45–0.52) cm]. No association between the existence of baseline ultrasound signs and development of symptoms in the following year was observed (Chi-Square: 1.180, p=0.277). A thicker baseline mid-tendon thickness was identified as a risk indicator for the development of Achilles tendinopathy in elite soccer players. PMID:23738247

Jhingan, Sachin; Perry, Mark; O'Driscoll, Gary; Lewin, Colin; Teatino, Raphael; Malliaras, Peter; Maffulli, Nicola; Morrissey, Dylan

2011-01-01

383

Tissue Engineering Strategies for the Tendon/ligament-to-bone insertion  

PubMed Central

Injuries to connective tissues are painful and disabling and result in costly medical expenses. These injuries often require re-attachment of an unmineralized connective tissue to bone. The uninjured tendon/ligament-to-bone insertion (enthesis) is a functionally graded material that exhibits a gradual transition from soft tissue (i.e., tendon or ligament) to hard tissue (i.e., mineralized bone) through a fibrocartilaginous transition region. This transition is believed to facilitate force transmission between the two dissimilar tissues by ameliorating potentially damaging interfacial stress concentrations. The transition region is impaired or lost upon tendon/ligament injury and is not regenerated following surgical repair or natural healing, exposing the tissue to risk of re-injury. The need to regenerate a robust tendon-to-bone insertion has led a number of tissue engineering repair strategies. This review treats the tendon-to-bone insertion site as a tissue structure whose primary role is mechanical and discusses current and emerging strategies for engineering the tendon/ligament-to-bone insertion in this context. The focus lies on strategies for producing mechanical structures that can guide and subsequently sustain a graded tissue structure and the associated cell populations. PMID:22185608

Smith, Lester; Xia, Younan; Galatz, Leesa M.; Genin, Guy M.; Thomopoulos, Stavros

2012-01-01

384

Scapular dyskinesis is detrimental to shoulder tendon properties and joint mechanics in a rat model.  

PubMed

Shoulder tendon injuries are frequently seen in the presence of abnormal scapular motion, termed scapular dyskinesis. The cause and effect relationship between scapular dyskinesis and shoulder injury has not been directly defined. We developed and used an animal model to examine the initiation and progression of pathological changes in the rotator cuff and biceps tendon. Sixty male Sprague-Dawley rats were randomized into two groups: nerve transection (to induce scapular dyskinesis, SD) or sham nerve transection (control). The animals were euthanized 4 and 8 weeks after surgery. Shoulder function and passive joint mechanics were evaluated over time. Tendon mechanical, histological, organizational, and compositional properties were evaluated at both time points. Gross observation demonstrated alterations in scapular motion, consistent with scapular "winging." Shoulder function, passive internal range of motion, and tendon mechanical properties were significantly altered. Histology results, consistent with tendon pathology (rounded cell shape and increased cell density), were observed, and protein expression of collagen III and decorin was altered. This study presents a new model of scapular dyskinesis that can rigorously evaluate cause and effect relationships in a controlled manner. Our results identify scapular dyskinesis as a causative mechanical mechanism for shoulder tendon pathology. PMID:25070580

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

2014-11-01

385

Effects of wrist tendon vibration on arm tracking in people poststroke  

PubMed Central

The goal of this study was to evaluate the influence of wrist tendon vibration on a multijoint elbow/shoulder tracking task. We hypothesized that tendon vibration applied at the wrist musculature would improve upper arm tracking performance in chronic stroke survivors through increased, Ia-afferent feedback to the central nervous system (CNS). To test this hypothesis, 10 chronic stroke and 5 neurologically intact subjects grasped the handle of a planar robot as they tracked a target through a horizontal figure-8 pattern. A total of 36 trials were completed by each subject. During the middle trials, 70-Hz tendon vibration was applied at the wrist flexor tendons. Position, velocity, and electromyography data were evaluated to compare the quality of arm movements before, during, and after trials with concurrent vibration. Despite tracking a target that moved at a constant velocity, hand trajectories appeared to be segmented, displaying alternating intervals of acceleration and deceleration. Segments were identifiable in tangential velocity data as single-peaked, bell-shaped speed pulses. When tendon vibration was applied at the wrist musculature, stroke subjects experienced improved tracking performance in that hand path lengths and peak speed variability decreased, whereas movement smoothness increased. These performance improvements were accompanied by decreases in the muscle activity during movement. Possible mechanisms behind improved movement control in response to tendon vibration may include improved sensorimotor integration or improved cortical modulation of spinal reflex activity. PMID:21697444

Conrad, Megan O.; Scheidt, Robert A.

2011-01-01

386

Radial Ridge Excision for Symptomatic Volar Tendon Subluxation Following de Quervain's Release.  

PubMed

Traditional surgical release to address de Quervain's stenosing tenosynovitis can lead to the rare complication of volar tendon subluxation. This study presents a surgical procedure, which entails excision of the radial ridge as an alternative treatment to relieve pain associated with symptomatic volar tendon subluxation following de Quervain's release. The procedure was performed on 6 patients complaining of painful volar tendon subluxation of abductor pollicis longus (APL) and extensor pollicis brevis (EPB), following a first dorsal compartment release and postoperative splinting. We opened the same incision sharply, with direct view of the tendons of the first dorsal compartment. The wrist was ranged through extension and flexion, and volar subluxation of the APL and EPB over the prominent radial ridge was confirmed. The bony portion of the radial ridge was excised and filed smooth. The periosteal flap is advanced over the ridge and sutured into place. The APL and EPB tendons were released from dorsal retractors. All patients reported relief upon follow-up. Excision of this ridge removes the obtrusive friction to the APL and EPB tendons, allowing them to glide painlessly over the radial styloid. PMID:24977493

Collins, Evan D

2014-09-01

387

An algorithm for automated analysis of ultrasound images to measure tendon excursion in vivo.  

PubMed

The accuracy of an algorithm for the automated tracking of tendon excursion from ultrasound images was tested in three experiments. Because the automated method could not be tested against direct measurements of tendon excursion in vivo, an indirect validation procedure was employed. In one experiment, a wire "phantom" was moved a known distance across the ultrasound probe and the automated tracking results were compared with the known distance. The excursion of the musculotendinous junction of the gastrocnemius during frontal and sagittal plane movement of the ankle was assessed in a single cadaver specimen both by manual tracking and with a cable extensometer sutured to the gastrocnemius muscle. A third experiment involved estimation of Achilles tendon excursion in vivo with both manual and automated tracking. Root mean squared (RMS) error was calculated between pairs of measurements after each test. Mean RMS errors of less than 1 mm were observed for the phantom experiments. For the in vitro experiment, mean RMS errors of 8-9% of the total tendon excursion were observed. Mean RMS errors of 6-8% of the total tendon excursion were found in vivo. The results indicate that the proposed algorithm accurately tracks Achilles tendon excursion, but further testing is necessary to determine its general applicability. PMID:18309186

Lee, Sabrina S M; Lewis, Gregory S; Piazza, Stephen J

2008-02-01

388

Computed tomography-guided bupivacaine and corticosteroid injection for the treatment of symptomatic calcification in the great toe tendon  

PubMed Central

Background Calcification in the great toe tendon is a rare disorder that is characterized by the deposition of calcium on degenerative collagen fibrils. Case presentations In this report, we present two cases of calcific tendonitis: one in the adductor hallucis and the other in the flexor hallucis longus tendon. We preferred computed tomography-guided steroid injection in our cases because of pain unresponsive to conservative treatment. Patients were free of symptoms at the follow-up visit, 4 weeks after injection. Conclusion Calcification of the hallux tendons is a rare disorder. Treatment of tendonitis consists of nonsteroidal anti-inflammatory drugs. Local anesthetic and steroid injection may be considered in cases unresponsive to conservative treatment. Because of the anatomic location of tendons, injection could be difficult. Computed tomography guidance may improve the success rate of injections. PMID:24872721

Karatoprak, Omer; Karaca, Sinan; Erdem, Mehmet Nuri; Karaman, Ozgur; Hamzaoglu, Azmi

2014-01-01

389

Does a Single Application of PRP Alter the Expression of IGF-I in the Early Phase of Tendon Healing?  

Microsoft Academic Search

The purpose of this study was to determine whether or not a single application of platelet-rich plasma (PRP) in a ruptured tendon alters the expression of IGF-I in the early phase of healing in an animal wound model. We performed an Achilles tendon rupture model on 48 New Zealand white rabbits, by transecting the tendon transversely and then injecting 0.5

Dimitris N. Lyras; Konstantinos Kazakos; George Georgiadis; George Mazis; Robert Middleton; Simon Richards; David O'Connor; George Agrogiannis

2011-01-01

390

Enhancement of rotator cuff tendon–bone healing with injectable periosteum progenitor cells-BMP-2 hydrogel in vivo  

Microsoft Academic Search

Purpose  The fixation and incorporation of ruptured rotator cuff tendon to bone is a major concern in rotator cuff repair surgery.\\u000a Rotator cuff repair usually fails at the tendon–bone interface, especially in case of large or massive tears. To enhance tendon–bone\\u000a healing, an injectable hydrogel made with periosteal progenitor cells(PPCs) and poly (ethylene glycol) diacrylate (PEGDA)\\u000a tethered with bone morphogenic protein-2(BMP-2)

Chih-Hwa Chen; Chih-Hsiang Chang; Kun-Chung Wang; Chun-I Su; Hsien-Tao Liu; Chung-Ming Yu; Chak-Bor Wong; I-Chun Wang; Shu Wen Whu; Hsia-Wei Liu

391

Tendinosis-like Histologic and Molecular Changes of the Achilles Tendon to Repetitive Stress: A Pilot Study in Rats  

Microsoft Academic Search

Background  Tendinopathy (pain and tendon degeneration) is associated with repetitive use and mechanical overload. However, the etiology\\u000a of tendinopathy remains unclear. Clarification of histologic and molecular changes of tendon to repetitive stress could provide\\u000a better understanding of Achilles tendon disorders related to repetitive stress.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/Purposes  We asked whether repetitive stress simulating overuse of the Achilles tendon induced (1) histologic changes in rats

Nam Soon Cho; Ji Hye Hwang; Yong Taek Lee; Seoung Wan Chae

392

Determining the Contribution of Glycosaminoglycans to Tendon Mechanical Properties with a Modified Shear-Lag Model  

PubMed Central

Tendon has a complex hierarchical structure composed of both a collagenous and a non-collagenous matrix. Despite several studies that have aimed to elucidate the mechanism of load transfer between matrix components, the roles of glycosaminoglycans (GAGs) remain controversial. Thus, this study investigated the elastic properties of tendon using a modified shear-lag model that accounts for the structure and non-linear mechanical response of the GAGs. Unlike prior shear-lag models that are solved either in two dimensions or in axially symmetric geometries, we present a closed-form analytical model for three-dimensional periodic lattices of fibrils linked by GAGs. Using this approach, we show that the non-linear mechanical response of the GAGs leads to a distinct toe region in the stress-strain response of the tendon. The critical strain of the toe region is shown to decrease inversely with fibril length. Furthermore, we identify a characteristic length scale, related to microstructural parameters (e.g. GAG spacing, stiffness, and geometry) over which load is transferred from the GAGs to the fibrils. We show that when the fibril lengths are significantly larger than this length scale, the mechanical properties of the tendon are relatively insensitive to deletion of GAGs. Our results provide a physical explanation for the insensitivity for the mechanical response of tendon to the deletion of GAGs in mature tendons, underscore the importance of fibril length in determining the elastic properties of the tendon, and are in excellent agreement with computationally intensive simulations. PMID:23932185

Ahmadzadeh, Hossein; Connizzo, Brianne K.; Freedman, Benjamin R.; Soslowsky, Louis J.; Shenoy, Vivek B.

2014-01-01

393

Human Achilles tendon plasticity in response to cyclic strain: effect of rate and duration.  

PubMed

High strain magnitude and low strain frequency are important stimuli for tendon adaptation. Increasing the rate and duration of the applied strain may enhance the adaptive responses. Therefore, our purpose was to investigate the effect of strain rate and duration on Achilles tendon adaptation. The study included two experimental groups (N=14 and N=12) and a control group (N=13). The participants of the experimental groups exercised according to a reference protocol (14 weeks, four times a week), featuring a high strain magnitude (~6.5%) and a low strain frequency (0.17 Hz, 3 s loading/3 s relaxation) on one leg and with either a higher strain rate (one-legged jumps) or a longer strain duration (12 s loading) on the other leg. The strain magnitude and loading volume were similar in all protocols. Before and after the interventions, the tendon stiffness, Young's modulus and cross-sectional area were examined using magnetic resonance imaging, ultrasound and dynamometry. The reference and long strain duration protocols induced significantly increased (P<0.05) tendon stiffness (57% and 25%), cross-sectional area (4.2% and 5.3%) and Young's modulus (51% and 17%). The increases in tendon stiffness and Young's modulus were higher in the reference protocol. Although region-specific tendon hypertrophy was also detected after the high strain rate training, there was only a tendency of increased stiffness (P=0.08) and cross-sectional area (P=0.09). The control group did not show any changes (P=0.86). The results provide evidence that a high strain magnitude, an appropriate strain duration and repetitive loading are essential components for an efficient adaptive stimulus for tendons. PMID:25267851

Bohm, Sebastian; Mersmann, Falk; Tettke, Martin; Kraft, Marc; Arampatzis, Adamantios

2014-11-15

394

Reduction in tendon elasticity from unloading is unrelated to its hypertrophy  

PubMed Central

Tendinous tissues respond to chronic unloading with adaptive changes in mechanical, elastic, and morphological properties. However, little is known about the changes in the detailed structures of the entire tendinous tissue and whether the change in tendon stiffness is related to morphology. We investigated changes in dimensional (volume, cross-sectional area, segmented lengths) and elastic (Young's modulus) properties of the Achilles tendon and distal aponeurosis in response to chronic unilateral lower limb suspension (ULLS) using velocity encoded phase contrast (VE-PC) and three-dimensional morphometric magnetic resonance imaging (MRI). Five healthy subjects underwent ULLS for 4 wk. Axial morphometric MRI was acquired along the entire length from the calcaneous to the medial gastrocnemius insertion. An oblique sagittal VE-PC MRI was also acquired. The Young's modulus could be calculated from this cine dynamic sequence of velocity encoded images from the slope of the stress-strain curve during the submaximal isometric plantar flexion. After 4 wk of ULLS, we found significant (46.7%) decrease in maximum plantar flexion torque. The total volumes of entire tendinous tissue (determined as the sum of the Achilles tendon and distal aponeurosis) increased significantly by 6.4% (11.9 vs. 12.7 ml) after ULLS. In contrast, Young's modulus decreased significantly by 10.4% (211.7 vs. 189.6 MPa) for the Achilles tendon and 29.0% for the distal aponeurosis (158.8 vs. 113.0 MPa) following ULLS. There was no significant correlation between relative change in volume and Young's modulus with 4 wk of ULLS. It is suggested that, although tendon hypertrophy can be expected to adversely affect tendon stiffness, the absence of any significant correlation between the magnitude of tendon hypertrophy and reduced Young's modulus indicates that dimensional factors were not critical to the elastic properties. PMID:20616227

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

2010-01-01

395

Determining the contribution of glycosaminoglycans to tendon mechanical properties with a modified shear-lag model.  

PubMed

Tendon has a complex hierarchical structure composed of both a collagenous and a non-collagenous matrix. Despite several studies that have aimed to elucidate the mechanism of load transfer between matrix components, the roles of glycosaminoglycans (GAGs) remain controversial. Thus, this study investigated the elastic properties of tendon using a modified shear-lag model that accounts for the structure and non-linear mechanical response of the GAGs. Unlike prior shear-lag models that are solved either in two dimensions or in axially symmetric geometries, we present a closed-form analytical model for three-dimensional periodic lattices of fibrils linked by GAGs. Using this approach, we show that the non-linear mechanical response of the GAGs leads to a distinct toe region in the stress-strain response of the tendon. The critical strain of the toe region is shown to decrease inversely with fibril length. Furthermore, we identify a characteristic length scale, related to microstructural parameters (e.g. GAG spacing, stiffness, and geometry) over which load is transferred from the GAGs to the fibrils. We show that when the fibril lengths are significantly larger than this length scale, the mechanical properties of the tendon are relatively insensitive to deletion of GAGs. Our results provide a physical explanation for the insensitivity for the mechanical response of tendon to the deletion of GAGs in mature tendons, underscore the importance of fibril length in determining the elastic properties of the tendon, and are in excellent agreement with computationally intensive simulations. PMID:23932185

Ahmadzadeh, Hossein; Connizzo, Brianne K; Freedman, Benjamin R; Soslowsky, Louis J; Shenoy, Vivek B

2013-09-27

396

Surgery for Retrocalcaneal Bursitis: A Tendon-splitting versus a Lateral Approach  

PubMed Central

For patients with refractory retrocalcaneal bursitis (Haglund’s syndrome), the most effective surgical approach has not been defined. We asked whether patients undergoing the tendon-splitting approach and the lateral approach would have comparably effective relief of pain for both types of calcaneal ostectomies. We retrospectively reviewed 30 patients (31 feet) who underwent the tendon-splitting approach and compared their results with 32 previous patients (35 feet) who had a lateral incision. Minimum followup was 12 months (mean, 16 months; range, 12–23 months) for the tendon-splitting group and 15 months (mean, 51 months; range, 15–109 months) for the lateral group. The mean American Orthopaedic Foot and Ankle Society score improved from 43 points preoperatively to 81 points (range, 8–100 points) postoperatively in the tendon-splitting group and from 54 points to 86 points (range, 55–100 points) in the lateral group. The mean physical component score of the Short Form-36, version 2, at followup was 52 (range, 22–61) in the tendon-splitting group and 49 (range, 34–63) in the lateral group. The median return to normal function was 4.1 months (range, 3–13 months) in the tendon-splitting group and 6.4 months (range, 4–20 months) in the lateral group. Both approaches to calcaneal ostectomy provided symptomatic pain relief. However, patients in the tendon-splitting group returned to normal function quicker than patients in the lateral group. Level of Evidence: Level III, retrospective comparative study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18465183

Anderson, John A.; Suero, Eduardo; O'Loughlin, Padhraig F.

2008-01-01

397

Autogenous tendon graft substitution for absent knee joint meniscus: a pilot study.  

PubMed

The purpose of this pilot study was to explore the potential of an autogenous tendon graft to substitute for an absent human knee joint meniscus. Based on the results of animal studies and human reports, it was hypothesized that autogenous tendon tissue would substitute for human knee joint meniscus: maintain mechanical integrity, convert to fibrocartilage, preserve the joint compartment, and provide symptomatic relief for the patient. Five patients, 2 men and 3 women, average age 41 years, had surgical absence of the lateral meniscus, genu valgum, and severe degenerative arthritis of the lateral compartment, but a stable knee. All patients were offered alternative treatments: do nothing, medication, arthroscopic debridement, osteotomy, and knee replacement. The operations were performed by arthroscopy. An accompanying arthroscopic debridement procedure was performed in the same compartment. In 4 cases, the donor graft was the semitendinosus tendon. In 1, the patellar tendon was used because the semitendinosus had been previously used in an anterior cruciate ligament reconstruction. Four of the 5 patients had a second-look arthroscopy and biopsy between 9 and 24 months. There was partial physical integrity to the tendon graft. The tendon graft did not completely convert to fibrocartilage. The joint surface was not preserved. Only 1 patient had minimal clinical improvement; the others were not improved. No patient was made worse. One patient had a total knee replacement 1 year later. Another had a knee fusion after 4 years. All other patients are considering future reconstructive surgery. The autogenous tendon graft as used in this pilot study was not successful as a substitute for an absent meniscus. The hypothesis was not realized. The observations from this pilot study should be helpful in future study protocol design. PMID:10705332

Johnson, L L; Feagin, J A

2000-03-01

398

Inflamm-Aging and Arachadonic Acid Metabolite Differences with Stage of Tendon Disease  

PubMed Central

The contribution of inflammation to the pathogenesis of tendinopathy and high prevalence of re-injury is not well established, although recent evidence suggests involvement of prostaglandins. We investigated the roles of prostaglandins and inflammation-resolving mediators in naturally occurring equine tendon injury with disease stage and age. Levels of prostaglandins E2 (PGE2), F2? (PGF2?), lipoxin A4 (LXA4) and its receptor FPR2/ALX were analysed in extracts of normal, sub-acute and chronic injured tendons. To assess whether potential changes were associated with altered PGE2 metabolism, microsomal prostaglandin E synthase-1 (mPGES-1), prostaglandin dehydrogenase (PGDH), COX-2 and EP4 receptor expression were investigated. The ability of tendons to resolve inflammation was determined by assessing FPR2/ALX expression in natural injury and IL-1? stimulated tendon explants. Alterations in the profile of lipid mediators during sub-acute injury included low PGE2 and elevated LXA4 levels compared to normal and chronic injuries. In contrast, PGF2? levels remained unchanged and were three-fold lower than PGE2. The synthetic capacity of PGE2 as measured by the ratio of mPGES-1:PGDH was elevated in sub-acute injury, suggesting aberrations in tendon prostaglandin metabolism, whilst COX-2 and EP4 receptor were unchanged. Paradoxically low tendon PGE2 levels in early injury may be attributed to increased local clearance via PGDH or the class switching of lipid mediators from the prostaglandin to the lipoxin axis. PGE2 is therefore implicated in the development of tendon inflammation and its ensuing resolution. Whilst there was no relationship between age and tendon LXA4 levels, there was an age-associated decline in FPR2/ALX receptor expression with concurrent increased PGE2 levels in injury. Furthermore, uninjured tendon explants from younger (<10 years) but not older horses (?10 years) treated with IL-1? responded by increasing FPR2/ALX suggesting aged individuals exhibit a reduced capacity to resolve inflammation via FPR2/ALX, which may present a potential mechanism for development of chronic tendinopathy and re-injury. PMID:23155437

Dakin, Stephanie Georgina; Dudhia, Jayesh; Werling, Natalie Jayne; Werling, Dirk; Abayasekara, Dilkush Robert Ephrem; Smith, Roger Kenneth Whealands

2012-01-01

399

The Incidence of Acute Traumatic Tendon Injuries in the Hand and Wrist: A 10-Year Population-based Study  

PubMed Central

Background Acute traumatic tendon injuries of the hand and wrist are commonly encountered in the emergency department. Despite the frequency, few studies have examined the true incidence of acute traumatic tendon injuries in the hand and wrist or compared the incidences of both extensor and flexor tendon injuries. Methods We performed a retrospective population-based cohort study of all acute traumatic tendon injuries of the hand and wrist in a mixed urban and rural Midwest county in the United States between 2001-2010. A regional epidemiologic database and medical codes were used to identify index cases. Epidemiologic information including occupation, year of injury, mechanism of injury and the injured tendon and zone were recorded. Results During the 10-year study period there was an incidence rate of 33.2 injuries per 100,000 person-years. There was a decreasing rate of injury during the study period. Highest incidence of injury occurred at 20-29 years of age. There was significant association between injury rate and age, and males had a higher incidence than females. The majority of cases involved a single tendon, with extensor tendon injuries occurring more frequently than flexor tendons. Typically, extensor tendon injuries involved zone three of the index finger, while flexor tendons involved zone two of the index finger. Work-related injuries accounted for 24.9% of acute traumatic tendon injuries. The occupations of work-related injuries were assigned to major groups defined by the 2010 Standard Occupational Classification structure. After assigning these patients' occupations to respective major groups, the most common groups work-related injuries occurred in construction and extraction occupations (44.2%), food preparation and serving related occupations (14.4%), and transportation and material moving occupations (12.5%). Conclusions Epidemiology data enhances our knowledge of injury patterns and may play a role in the prevention and treatment of future injuries, with an end result of reducing lost work time and economic burden. PMID:24900902

de Jong, Johanna P.; Nguyen, Jesse T.; Sonnema, Anne J. M.; Nguyen, Emily C.; Amadio, Peter C.

2014-01-01

400

Reduction of Tendon Adhesions following Administration of Adaprev, a Hypertonic Solution of Mannose-6-Phosphate: Mechanism of Action Studies  

PubMed Central

Repaired tendons may be complicated by progressive fibrosis, causing adhesion formation or tendon softening leading to tendon rupture and subsequent reduced range of motion. There are few therapies available which improve the gliding of damaged tendons in the hand. We investigate the role of Mannose 6-phosphate (M6P) in a 600 mM hypertonic solution (Adaprev) on tendon adhesion formation in vivo using a mouse model of severed tendon in conjunction with analysis of collagen synthesis, cellular proliferation and receptors involved in TGF beta signalling. Cytotoxicity was assessed by measuring tissue residency, mechanical strength and cell viability of tendons after treatment with Adaprev. To elicit potential modes of action, in vitro and ex vivo studies were performed investigating phosphorylation of p38, cell migration and proliferation. Adaprev treatment significantly (p<0.05) reduced the development of adhesions and improved collagen organisation without reducing overall collagen synthesis following tendon injury in vivo. The bioavailability of Adaprev saw a 40% reduction at the site of administration over 45 minutes and tendon fibroblasts tolerated up to 120 minutes of exposure without significant loss of cell viability or tensile strength. These favourable effects were independent of CI-MPR and TGF-? signalling and possibly highlight a novel mechanism of action related to cellular stress demonstrated by phosphorylation of p38. The effect of treatment reduced tendon fibroblast migration and transiently halted tendon fibroblast proliferation in vitro and ex vivo. Our studies demonstrate that the primary mode of act