Tendon Repair Research Articles

Wrist-Level Tendon Repairs Utilizing a Novel Tendon Stapler Device: An Efficiency and Biomechanical Study.

A novel tendon stapler device (TSD) to improve the strength and consistency of primary tendon repairs was recently approved by the U.S. Food and Drug Administration. The authors hypothesized that this TSD would demonstrate faster and superior biomechanical properties compared with a standard suture coaptation. The authors also hypothesized that the TSD biomechanical properties would be consistent across participants with differing tendon repair experiences. Participants included a novice, intermediate, and expert in tendon repairs. Timed comparisons were performed in flexor zones IV and V and extensor zones VI and VII on human cadaver arms. Suture repairs were performed with a modified Kessler technique with a horizontal mattress. TSD repairs were performed on the matched donor arms. Biomechanical testing included 2-mm gap force, ultimate failure load, and mode of failure. In total, 228 tendon coaptations from 12 donor arms were performed and analyzed. TSD coaptations were 3 times faster and withstood nearly 50% higher forces on 2-mm gap testing and roughly 30% higher forces on ultimate failure testing. These findings did not change when the repair times were analyzed by participant. Suture coaptations failed owing to suture pull-through, suture breakage, or knot failure. TSD coaptation failures only occurred from device pull-through. The TSD produces significantly faster and stronger primary tendon coaptations compared with a standard 4-strand core suture repair in human donor arms. The findings demonstrated minimal variability among participants with differing tendon repair experience. Although further investigation is needed, this device has potential to revolutionize tendon repairs.

One Step Double Augmentation with Human Dermis Allograft and Homologous PRP in Misdiagnosed and or Chronic Achilles Tendon Ruptures.

Misdiagnosed/chronic Achilles tendon injuries are rare and disabling for patients. The surgical treatment of these rare injuries aims to ensure the tendon heals mechanically and biologically. This is the prerequisite for a good clinical and functional outcome and reduces recurrences. The main aim of the study is to present a surgical technique that has proven to be original, reproducible, and capable of guaranteeing solid tendon repair and optimal tissue regeneration. We treated five patients, four males and one female, with the one-step double augmentation technique. All patients of this study complained of pain, but above all severe functional limitation that Achilles tendon injury had been causing for more than a month. In this study, we widely described the surgical technique, original and not found in the literature, which provides a biological graft (allograft of decellularized dermis) and homologous, thrombin-activated, platelet-rich plasma (H-PRP) in a single step. Surgical approach, always used by the first author, respected predefined steps: careful dissection and preparation of the peritendinous tissues from suture to the end of the procedure, tenorrhaphy, and augmentation with allopatch to obtain a mechanically effective repair to avoid recurrences, and finally "biological" augmentation with a unit of homologous, thrombin activated, PRP. We offered to all patients a regenerative rehabilitation program post-operatively. All patients were evaluated clinically (functional clinical tests and questionnaires) and instrumentally (elastic-sonography and perfusion MRI). The obtained results have been evaluated at a minimum follow-up of 18 months and a maximum of 24 months. In all patients pain was resolved, and district function and kinetic chains improved with resumption of daily activities, work, and sports. The present study confirmed the regenerative potential of decellularized dermis allograft and PRP (homologous and thrombin-activated). The same approach can also be exploited in cases of severe tendon destructuring and limited "intrinsic" regenerative potential at any age. The proposed one-step surgical technique of a double augmentation therefore appears useful, safe, reproducible, and applicable in all chronic tendon lesions with low regenerative potential.

The effect of smoking on 30-day complications following primary repair of Achilles tendon ruptures.

There exists a gap in the knowledge of the impact of smoking on Achilles tendon rupture repair. This study evaluates perioperative and postoperative complications associated with smoking to allow for a more informed evaluation and discussion with the patients when considering the surgical management of Achilles tendon repair in this patient population. The National Surgical Quality Improvement Program database was queried for patients undergoing Achilles tendon rupture repair from 2006 to 2019. Two patient cohorts were defined in this retrospective study: smokers and patients who did not smoke. The various patient demographics, medical comorbidities, and postoperative outcomes were compared using bivariate and multivariate analyses between the smoking and non-smoking groups. Of 4209 patients who underwent Achilles tendon repair, 3662 patients (87%) did not smoke, whereas 547 patients (13%) were smokers. Patients who were smokers were more likely to be younger and have a higher body mass index. Following multivariate analyses, those who smoked had an increased risk of experiencing wound dehiscence (OR 3.57; p = 0.013) and urinary tract infections (OR 1.21; p = 0.033) compared to non-smoking patients. Despite the rate of complications being relatively low in the short-term perioperative period, individuals who smoke should be counseled on the surgical risks they may experience following Achilles tendon repair, including wound dehiscence and urinary tract infections. Discussion preoperatively between the physician and patient who smoke can include ways in which postoperative care will be done to minimize the risk of adverse events, ultimately reducing costs for both the patient and the hospital.

Postoperative Management Early Active Mobilization of Extensor Tendon Repair at Zone (V-VII)

Background: The extensor tendons are particularly vulnerable to trauma because their superficial location in a clenched fist, the thin mobile subcutaneous tissue offers little protection, and lacerations of the extensor tendons are common over joints that are easily exposed to contamination. Objective: To assess the evaluation of the postoperative early active mobilization protocol of extensor tendon repair at zone (V-VII). Methods: In this prospective study was carried out at Orthopedic Dept., 250 Bed General Hospital, Kishoreganj, Bangladesh from January to June 2023. Total 40 cases of fresh injury of extensor tendon at zone V to VII were treated. A protocol of early active mobilization was undertaken, using an easy to follow rehabilitation plan. Routine history taking with details of the injury, the object causing the injury, the dominant hand and the position during the injury, Physical examination, included the zone, and the possible tendons involved together with any associated injury. Results: Forty patients of fresh extensor tendon injuries were included in this study, their ages ranged from 20 to 55 years. There were 33 males (82.5%) and 7 females (17.5%). The dominant hand was involved in 29 of patients (72.5%). The nature of injuries was sharp cut in 34 patients (85%), with crush injuries in 6 patients (15%). The most common site of injuries was zone VI, VII and zone V respectively, and the most common tendon injured was EDC, EI, and EDM. Only 7 patients (17.5%) had single tendon injury, While 33 patients (82.5%) had multiple tendon injuries. At the end of the 6th weeks post operatively, the overall outcome result are summarized. Conclusion: The early mobilization of repaired extensor tendon reduces the formation of adhesion as compared to rigid immobilization. We recommend the use of this protocol following extensor tendon repair in the hand at zone V, VI, and VII in cooperative patient. It will give fairly acceptable results.

A Novel Achilles Tendon Repair Technique Utilizing a Bio-Composite Scaffold for a Sub-Acute Tear.

Achilles tendon ruptures are prevalent musculoskeletal injuries accounting for 20% of all large tendon ruptures with a re-rupture rate of 2.1-8.8%. Ineffectual management of these injuries can lead to a significant loss in push-off strength and overall ankle function. The field of orthopedic surgery has shown an increasing interest in biologic augmentation. Encouraged by its success in various other applications, this approach holds promise for potentially enhancing outcomes in Achilles tendon repairs, especially in poor tendon tissue. The BioBrace® (ConMed, New Haven, Connecticut) is a biocomposite scaffold made of highly porous type I collagen and bioresorbable poly (L-Lactide) (PLLA) microfilaments. It can be applied in conjunction with Achilles tendon repair or reconstruction. It provides immediate strength to the augmented repair upon implantation and simultaneously promotes new, organized tissue growth throughout its resorptive phase. Here, we outline a technique to effectively augment an acute Achilles tendon repair utilizing the BioBrace® reinforced bio-inductive implant.

Implantable Biologics for Soft Tissue Surgery Reinforcement.

Soft tissue reinforcement focuses on medical grafts that are designed to support and regenerate soft tissue under or near suture lines. Soft tissue is defined as areas of similarly specialized cells that function to connect, support, and surround other structures and organs of the body. These tissues include skin, subcutaneous tissue, fascia, ligaments, tendons, fibrous tissues, fat, synovial membranes, and muscle. Most of the implantable devices used for this purpose are made of collagen, the most abundant protein in mammals and a key component of the extracellular matrix of soft tissues that allows for tissue repair. For suture line reinforcement, exogenous collagen from various sources is implanted under or in continuity with the suture line to allow for increased strength and better healing. First introduced in the field of breast reconstruction, this practice is now also used in hernia repair, dural repair, vaginal slings, amputation reinforcement, tendon repair reinforcement, and even dental soft tissue regeneration.

Adjustable Cortical Fixation Repair Is a Safe and Effective Technique for Quadriceps Tendon Rupture

To report the clinical outcomes of quadriceps tendon repair using adjustable cortical fixation devices at a minimum 2-year follow-up. A retrospective chart review identified patients who underwent quadriceps tendon repair using adjustable cortical fixation devices between January 2017 and March 2020. Patients with a partial tendon rupture were excluded. Demographic and injury-specific variables were gathered preoperatively and postoperatively from the electronic medical record and patient-reported outcomes (Lysholm Knee Questionnaire, Lower Extremity Functional Scale, and SF-12) were collected via telephone at a minimum of 2 years postoperatively. Fourteen quadriceps tendon repairs were included in a total of 13 patients. The average time to follow-up was 3.5 ± 1.2 years with a range of 1.9 to 5.7 years. The mean age of this cohort was 55.7 ± 11.6 years, and the mean body mass index was 32.9 ± 6.0. Ten injuries (71.4%) were sustained by mechanical fall, 2 patients (14.3%) suffered a direct blow to the knee, and 2 patients (14.3%) reported a noncontact injury mechanism. Thirteen quadriceps ruptures (13/14, 92.9%) underwent surgery within 10 days of their injury. One knee (7.1%) had a postoperative extensor lag of 5°, whereas another knee (7.1%) required a reoperation for manipulation under anesthesia and arthroscopic lysis of adhesions at 3 months' postoperatively. None of the included patients (0.0%) developed a tendon re-rupture, venous thromboembolism, delayed wound healing, surgical-site infection, neuropraxia or nerve injury, hardware irritation, patella fracture, or heterotopic ossification. In this study, adjustable cortical fixation was a safe and effective surgical technique for quadriceps tendon repair, with adequate restoration of quadriceps function and a low rate of adverse events at 2 years postoperatively. Level IV, therapeutic case series.

HPF1 regulates tendon stem/progenitor cell senescence and tendon repair via PARP1-mediated poly-ADP ribosylation of HuR.

Tendon stem/progenitor cells (TSPCs) play a vital role in tendon repair, regeneration and homeostasis. However, the specific mechanism of TSPCs aging is still unclear. This study aims to explore the role and molecular mechanism of HPF1 in the aging of TSPCs. Young and aged TSPCs (Y-TSPCs and A-TSPCs) were acquired from 3 to 4 and 24-26-month-old Sprague-Dawley male rats, TSPCs (Y-TSPCs and A-TSPCs) were subjected to senescence-associated β-galactosidase (SA-β-Gal))staining and telomerase activity detection, p16, p21, Scx, Tnmd, Col1, Col3HPF1 and PAPR1 expression levels were detected by Western blot or Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR), Reciprocal co-immunoprecipitation (co-IP) was used to explore the interaction between HPF1 and PARP1. Ribonucleoprotein immunoprecipitation (RNP-IP) was used to analyze the binding of HuR to the senescence marker gene mRNAs, IP was used to perform HPF1 to the PARylation of HuR, and the half-life of p16 and p21 were detected. Finally, we established an in vivo model, and the tendon tissue was used to perform hematoxylin and eosin (HE) and masson's trichrome staining, as well as the immunohistochemical analysis of Col I and TNMD. Compared with Y-TSPCs, A-TSPCs had significantly enhanced cell senescence and significantly reduced tendon differentiation ability, and significantly increased the expression of HPF1 and PARP1. In addition, HPF1 and PARP1 interacted and coordinated the senescence and differentiation of TSPCs, HPF1 could also regulate the expression of p21 and p21, the interaction of p16 or p21 with HuR, and the poly-ADP ribosylation of PARP1 to HuR. HPF1 overexpression and siHuR co-transfection significantly reduced the half-life of p16 and p21, and HPF1 and PARP1 regulated the mRNA levels of p16 and p21 through HuR. Finally, in vivo experiments have shown that HPF1 or PARP1 overexpression could both inhibit the ability of tendon differentiation and promote cell senescence. HPF1 promoted the senescence of TSPCs and inhibits the tendon differentiation of TSPCs through PARP1-mediated poly-ADP ribosylation of HuR.

Morphological, histological and biomechanical comparison of bone marrow aspirate concentrate, micro-fragmented adipose tissue and platelet-rich plasma in prevention of tendon adhesion

Flexor tendon repair often leads to peritendinous adhesions, reducing finger motion and hand function. This study compares the effects of stromal cells from different sources and platelet-rich plasma (PRP) on adhesion formation after tendon repair. Forty rabbits had their flexor digitorum profundus tendons transected and repaired with a modified Kessler suture technique. The control group received an isotonic solution. PRP, bone marrow aspirate concentrate (BMAC), and micro-fragmented adipose tissue (MFAT) were injected in groups 2, 3, and 4, respectively. Rabbits wore casts for 2 weeks. Assessments included morphology, histopathology, range of motion (ROM), and biomechanical testing at the 3rd and 8th weeks. At 3 weeks, the BMAC group had the thickest and longest adhesions, the highest Tang Score, and inflammation score. However, at 8 weeks, the BMAC group had the lowest Tang Score and inflammation score. ROM was higher in the PRP group at 3 weeks and BMAC group at 8 weeks. No significant differences were found between BMAC and MFAT groups in adhesion measurements. Biomechanical parameters were higher in BMAC and MFAT groups at 8 weeks compared to control. BMAC therapy after primary flexor tendon repair improves adhesion formation and maintains ROM. It also enhances the biomechanical properties of the flexor tendon during the later stages of healing.

Rotator Cuff Repair and Overlay Augmentation by Direct Interlocking of a Nonwoven Polyethylene Terephthalate Patch Into the Tendon: Evaluation in an Ovine Model

Background: Arthroscopic repair of large rotator cuff tendon tears is associated with high rates of retear. Construct failure often occurs at the suture-tendon interface. Patch augmentation can improve mechanical strength and healing at this interface. Purpose: To introduce a novel technique for suture-free attachment of an overlaid patch and evaluate its biomechanical strength and biological performance. Study Design: Descriptive and controlled laboratory studies. Methods: An established ovine model of partial infraspinatus tendon resection and immediate repair was used. After a nonwoven polyethylene terephthalate patch was overlaid to the resected tendon, a barbed microblade was used to draw fibers of the patch directly into the underlying tissue. In vivo histological assessment of healing was performed at 6 and 13 weeks after implantation. Ex vivo models were used to characterize primary repair strength of the suture-free patch fixation to tendon. Additional ex vivo testing assessed the potential of the technique for patch overlay augmentation of suture-based repair. Results: The in vivo study revealed no macroscopic evidence of adverse tissue reactions to the interlocked patch fibers. Histological testing indicated a normal host healing response with minimal fibrosis. Uniform and aligned tissue ingrowth to the core of the patch was observed from both the tendon and the bone interfaces to the patch. There was no evident retraction of the infraspinatus muscle, lengthening of the tendon, or tendon gap formation over 13 weeks. Ex vivo testing revealed that direct patch interlocking yielded tendon purchase equivalent to a Mason-Allen suture (150 ± 58 vs 154 ± 49 N, respectively; P = .25). In an overlay configuration, fiber interlocked patch augmentation increased Mason-Allen suture retention strength by 88% (from 221 ± 43 N to 417 ± 86 N; P < .01) with no detectable difference in repair stiffness. Conclusion: Testing in an ovine model of rotator cuff tendon repair suggested that surgical interlocking of a nonwoven medical textile can provide effective biomechanical performance, support functional tissue ingrowth, and help avoid musculotendinous retraction after surgical tendon repair. Clinical Relevance: The novel technique may facilitate patch augmentation of rotator cuff repairs.

Complement factor D regulates collagen type I expression and fibroblast migration to enhance human tendon repair and healing outcomes.

Dense connective tissues (DCTs) such as tendon, ligament, and cartilage are important stabilizers and force transmitters in the musculoskeletal system. The healing processes after DCT injuries are highly variable, often leading to degenerative changes and poor clinical outcome. Biomarkers in relation to repair quality for human DCTs, especially tendon are lacking. This study expands our previous findings and aimed to characterize the mechanisms by which a potential biomarker of good outcomes, complement factor D (CFD), regulates tendon healing. Quantitative mass spectrometry (QMS) profiling of tissue biopsies from the inflammatory phase of healing (n = 40 patients) and microdialysates from the proliferative phase of healing (n = 28 patients) were used to identify specific biomarkers for tendon healing. Further bioinformatic and experimental investigations based on primary fibroblasts and fibroblast cell line were used to confirm the identified biomarkers. The QMS profiling of tissue biopsies from the inflammatory phase of healing identified 769 unique proteins, and microdialysates from the proliferative phase of healing identified 1423 unique proteins in Achilles tendon rupture patients. QMS-profiling showed that CFD expression was higher during the inflammatory- and lower during the proliferative healing phase in the good outcome patients. Further bioinformatic and experimental explorations based on both inflammatory and proliferative fibroblast models demonstrated that CFD potentially improved repair by regulating cell migration and modulating collagen type I (Col1a1) expression. Moreover, it was shown that the enhanced Col1a1 expression, through increased fibroblast migration, was correlated with the validated clinical outcome. The results of the current studies characterized underlying inflammatory- and proliferative healing mechanisms by which CFD potentially improved tendon repair. These findings may lead to improved individualized treatment options, as well the development of effective therapies to promote good long-term clinical outcomes after tendon and other DCT injuries. http://clinicaltrials.gov, identifiers NCT02318472, NCT01317160.

A novel biplanar repair technique for tendoachilles tendon ruptures

Objectives: Achilles tendon is one of the most commonly ruptured tendons in the body. Conservative and operative treatment is both well-described in the literature. Surgical treatment carries risks and complications, which we tried to overcome with our novel biplanar repair technique. Materials and methods: The unique features of our technique include an incision with intact skin bridge, repair of tendoachilles tendon with mediolateral and anteroposterior tunnels in calcaneal tuberosity and a post-operative cast permitting knee flexion, preventing knee extension. Results: The results of this technique after 1 year of follow-up showed no wound-related complications, no rerupture, and an average American Orthopedic Foot and Ankle Society score of 92. Conclusion: It is a promising technique and further studies are needed to compare the results of our technique with existing ones over longer periods.

Validation of the Efficacy of Ultrasound Speckle Tracking in Measuring Tendon Gliding After Finger Flexor Tendon Repair.

Restricted tendon gliding is commonly observed in patients after finger flexor tendon (FFT) repair. The study described here was aimed at quantifying the amount of FFT gliding to evaluate the recovery of post-operative tendons using a 2-D radiofrequency (RF)-based ultrasound speckle tracking algorithm (UST). Ex vivo uniaxial tensile testing of porcine flexor tendons and in vivo isometric testing of human FFT were implemented to verify the efficacy of UST beforehand. The verified UST was then applied to the patients after FFT repair to compare tendon gliding between affected and healthy sides and to investigate its correlation with the joint range of motion (ROM). Excellent validity was confirmed with the average R2 value of 0.98, mean absolute error of 0.15 ± 0.08 mm and mean absolute percentage error of 5.19 ± 2.43% between results from UST and ex vivo testing. The test-retest reliability was verified with good agreement of ICC (0.90). The affected side exhibited less gliding (p=0.001) and smaller active ROM (p=0.002) than the healthy side. Meanwhile, a significant correlation between tendon gliding and passive ROM was found only on the healthy side (ρ=0.711, p=0.009). The present study provides a promising protocol to evaluate post-operative tendon recovery by quantifying the amount of FFT gliding with a validated UST. FFT gliding in patients with different levels of ROM restriction should be further explored for categorizing the severity of tendon adhesion.

Tendon Repair and Regeneration Using Bioinspired Fibrillation Engineering That Mimicked the Structure and Mechanics of Natural Tissue.

Replicating the controlled nanofibrillar architecture of collagenous tissue represents a promising approach in the design of tendon replacements that have tissue-mimicking biomechanics─outstanding mechanical strength and toughness, defect tolerance, and fatigue and fracture resistance. Guided by this principle, a fibrous artificial tendon (FAT) was constructed in the present study using an engineering strategy inspired by the fibrillation of a naturally spun silk protein. This bioinspired FAT featured a highly ordered molecular and nanofibrillar architecture similar to that of soft collagenous tissue, which exhibited the mechanical and fracture characteristics of tendons. Such similarities provided the motivation to investigate FAT for applications in Achilles tendon defect repair. In vitro cellular morphology and expression of tendon-related genes in cell culture and in vivo modeling of tendon injury clearly revealed that the highly oriented nanofibrils in the FAT substantially promoted the expression of tendon-related genes combined with the Achilles tendon structure and function. These results provide confidence about the potential clinical applications of the FAT.

Approach for Neglected Calcaneal Fracture-Dislocation and Associated Complications

Calcaneal fractures lead to significant debility that can be increased due to delayed or improper surgical repair and are commonly complicated by nonunion. This report explores a unique case of neglected calcaneal fracture with malalignment complicated by subluxing peroneal tendons, arthritis of the hindfoot, and tear of the peroneal retinaculum. The operative intervention consisted of open Achilles tendon lengthening, bone block distraction arthrodesis of the subtalar joint with talonavicular and calcaneocuboid fusion, along with repair of subluxing peroneal tendons with fibular groove deepening. Postoperative imaging at 25 weeks revealed intact hardware, stable alignment, and complete osseous arthrodesis of involved joints, which was also redemonstrated at 1-year postoperative. Reports of reconstructive options for neglected calcaneal fractures that restore mobility, such as this case, are important due to the significant patient burden these injuries impose and the paucity of viably restorative options currently available. Level of Evidence: Level-IV.

Experiences in assessment, replacement and repair of external tendons

AbstractThe paper presents experiences with damages that occurred when using external tendons. Reason for these damages could be both technical deficiencies of a tendon system (system = components, design, corrosion protection, installation, stressing etc.) or simply human mistakes. Damages often could occur at deviators and anchorages, since forces are transferred to the structure there and the tendon is loaded in transverse direction. Damages will be presented, explained (why it is a damage), which measure had been taken and of course also advice for the future (lessons learned). The damages occurred on site or during testing of external tendon systems. Hence, the paper shall help the reader/attendant to understand sensitivity of external tendons. Furthermore, to these damages experiences with replacement (mainly cutting of the old tendon) of external tendons with flexible filler mass are shared. “Experience” focusses mainly on the de‐installation, re‐installation, grouting and stressing process. Topics that will be covered are:‐ Improper design and/or installation of deviators and subsequent damages to the tendon sheath‐ Torsional strand failure due to improper deviation at stressing anchor‐ Limitations of the tendon path‐ Deficient encapsulation of the prestressing steel‐ Tendon force measurement options

Structural Musculotendinous Parameters That Predict Failed Tendon Healing After Rotator Cuff Repair.

Healing of the rotator cuff after repair constitutes a major clinical challenge with reported high failure rates. Identifying structural musculotendinous predictors for failed rotator cuff repair could enable improved diagnosis and management of patients with rotator cuff disease. To investigate structural predictors of the musculotendinous unit for failed tendon healing after rotator cuff repair. Cohort study; Level of evidence, 2. Included were 116 shoulders of 115 consecutive patients with supraspinatus (SSP) tear documented on magnetic resonance imaging (MRI) who were treated with an arthroscopic rotator cuff repair. Preoperative assessment included standardized clinical and imaging (MRI) examinations. Intraoperatively, biopsies of the joint capsule, the SSP tendon, and muscle were harvested for histological assessment. At 3 and 12 months postoperatively, patients were re-examined clinically and with MRI. Structural and clinical predictors of healing were evaluated using logistic and linear regression models. Structural failure of tendon repair, which was significantly associated with poorer clinical outcome, was associated with older age (β = 1.12; 95% CI, 1.03 to 1.26; P = .03), shorter SSP tendon length (β = 0.89; 95% CI, 0.8 to 0.98; P = .02), and increased proportion of slow myosin heavy chain (MHC)-I/fast MHC-II hybrid muscle fibers (β = 1.23; 95% CI, 1.07 to 1.42; P = .004). Primary clinical outcome (12-month postoperative Constant score) was significantly less favorable for shoulders with fatty infiltration of the infraspinatus muscle (β = -4.71; 95% CI, -9.30 to -0.12; P = .044). Conversely, a high content of fast MHC-II muscle fibers (β = 0.24; 95% CI, 0.026 to 0.44; P = .028) was associated with better clinical outcome. Both decreased tendon length and increased hybrid muscle fiber type were independent predictors for retear. Clinical outcome was compromised by tendon retearing and increased fatty infiltration of the infraspinatus muscle. A high content of fast MHC-II SSP muscle fibers was associated with a better clinical outcome. NCT02123784 (ClinicalTrials.govidentifier).

Systematic Review of Complications Associated With Proximal Hamstring Tendon Repair.

Although several complications of proximal hamstring tendon ruptures have been reported in the literature, few studies have comprehensively analyzed the complication profile of proximal hamstring tendon repair. To identify the overall rate of complications following proximal hamstring tendon repair and to differentiate these complications into categories. Systematic review; Level of evidence, 4. Included in this review were studies that examined surgical repair of proximal hamstring tendon ruptures; all studies were in English and had an evidence level of 4 or higher. No restrictions were made regarding publication date or methodological quality. Data regarding complications were extracted to calculate the overall complication rate as well as the rate of major and minor complications. A quantitative data synthesis was conducted using the chi-square test to compare the proportion of patients who experienced complications with the endoscopic versus open approach. A total of 43 articles including 2833 proximal hamstring tendon repairs were identified. The overall postoperative complication rate was 15.3% (n = 433). The rate of major complications was 4.6%, including a 1.7% rate of sciatic nerve injury, 0.8% rate of venous thromboembolism, 0.8% reoperation rate, 0.8% rerupture rate, and 0.4% rate of deep infection. Minor complications included a 2.4% rate of posterior femoral cutaneous nerve injury, 2.3% rate of persistent hamstring myopathy, 2.2% rate of persistent sitting pain, 1.8% rate of peri-incisional numbness, 1.1% rate of superficial infection, and 0.8% rate of hematoma/seroma. Proximal hamstring tendon repair is associated with an overall complication rate of 15.3%, including a 4.6% rate of major complications.

Minimally invasive distal biceps tendon repair: a case series.

Distal biceps tendon repairs are commonly performed using open techniques. A minimally invasive distal biceps tendon repair technique using a speculum and hooded endoscope was developed to improve visualization, reduce soft-tissue dissection, and minimize complications. This paper describes the technique and reports the outcomes of 75 minimally invasive distal biceps tendon repairs. The operation reports and outcomes of 75 patients who underwent distal biceps tendon repair using this technique between 2011 and 2021 were retrospectively reviewed. Median time to follow-up was 12 months (interquartile range [IQR], 6-56 months). Primary outcomes were function as measured by the Disabilities of Arm, Shoulder and Hand Score (DASH) questionnaire, and rate of complications. Median DASH score was 1.7 of 100 (IQR, 0-6.8). There were 2 of 75 (2.7%) re-ruptures of the distal tendon. There were no cases of vascular injury, proximal radius fracture, or posterior interosseous nerve, median, or ulnar nerve palsy. In this series, minimally invasive distal biceps repair was safe and effective with a low rate of major complications. Recovery of function, as indicated by low DASH scores, was satisfactory, and inconvenience during recovery was minimized. Level of evidence: IV.

Engineered Tissue Graft for Repair of Injured Infraspinatus Rotator Cuff Tendon.

Rotator cuff tears constitute a vast majority of shoulder-related injuries, occurring in a wide population range and increasing in incidence with age. Current treatments for full thickness tears use suture to secure the ruptured tendon back to its native attachment site and often retear due to improper enthesis regeneration. To reduce the occurrence of retear, our laboratory developed an engineered tendon graft for rotator cuff repair (ETG-RC) to serve as an underlayment to traditional suture repair. We hypothesize the ETG-RC will aid in the repair of the torn rotator cuff tendon by promoting the regeneration of a functional enthesis. This devitalized graft fabricated from ovine-derived bone marrow stromal cells was evaluated for biomechanical and histomorphology properties in an ovine infraspinatus rotator cuff repair model. Compared with a current standard practice Suture-Only model, the ETG-RC repair showed comparable high strain-to-failure forces, greater fibrocartilage deposition, regeneration of zonal gradients, and Shapey's fibers formation, indicative of enthesis regeneration. Enthesis regeneration after rotator cuff repair should repair mechanical properties and alleviate the need for subsequent surgeries required due to retear. The ETG-RC could potentially be used for repairing other tendon injuries throughout the body.