Aims. Acute distal biceps tendon repair reduces fatigue-related pain and minimizes loss of supination of the forearm and strength of flexion of the elbow. We report the short- and long-term outcome following repair using fixation with a cortical button techqniue. Methods. Between October 2010 and July 2018, 102 patients with a mean age of 43 years (19 to 67), including 101 males, underwent distal biceps tendon repair less than six weeks after the injury, using cortical button fixation. The primary short-term outcome measure was the rate of complications. The primary long-term outcome measure was the abbreviated Disabilities of the Arm, Shoulder and Hand (QuickDASH) score. Secondary outcomes included the Oxford Elbow Score (OES), EuroQol five-dimension three-level score (EQ-5D-3L), satisfaction, and return to function. Results. Eight patients (7.8%) had a major complication and 34 (33.3%) had a minor complication. Major complications included re-rupture (n = 3; 2.9%), unrecovered nerve injury (n = 4; 3.9%), and surgery for heterotopic ossification (n = 1; 1.0%). Three patients (2.9%) overall required further surgery for a complication. Minor complications included neurapraxia (n = 27; 26.5%) and superficial infection (n = 7; 6.9%). A total of 33 nerve injuries occurred in 31 patients (30.4%). At a mean follow-up of five years (1 to 9.8) outcomes were available for 86 patients (84.3%). The median QuickDASH, OES, EQ-5D-3L, and satisfaction scores were 1.2 (IQR 0 to 5.1), 48 (IQR 46 to 48), 0.80 (IQR 0.72 to 1.0), and 100/100 (IQR 90 to 100), respectively. Most patients were able to return to work (81/83, 97.6%) and sport (51/62,82.3%). Unrecovered nerve injury was associated with an inferior outcome according to the QuickDASH (p = 0.005), OES (p = 0.004), EQ-5D-3L (p = 0.010), and satisfaction (p = 0.024). Multiple linear regression analysis identified an unrecovered nerve injury to be strongly associated with an inferior outcome according to the QuickDASH score (p < 0.001), along with infection (p < 0.001), although re-rupture (p = 0.440) and further surgery (p = 0.652) were not. Conclusion. Acute distal biceps tendon repair using cortical button fixation was found to result in excellent patient-reported outcomes and health-related quality of life. Although rare, unrecovered nerve injury adversely affects outcome. Cite this article: Bone Joint J 2021;103-B(7):1284–1291

Thrombin has many biological properties similar to those of growth factors. In a previous study, we showed that thrombin improves healing of the rat tendo Achillis. Low molecular weight heparin (LMWH) inhibits the activity and the generation of thrombin. We therefore considered that LMWH at a thromboprophylactic dose might inhibit tendon repair. Transection of the tendo Achillis was carried out in 86 rats and the healing tested mechanically. Low molecular weight heparin (dalateparin) was either injected a few minutes before the operation and then given continuously with an osmotic mini pump for seven days, or given as one injection before the operation. In another experiment ,we gave LMWH or a placebo by injection twice daily. The anti-factor Xa activity was analysed. Continuous treatment with LMWH impaired tendon healing. After seven days, this treatment caused a 33% reduction in force at failure, a 20% reduction in stiffness and a 67% reduction in energy uptake. However, if injected twice daily, LMWH had no effect on tendon healing. Anti-factor Xa activity was increased by LMWH treatment, but was normal between intermittent injections. Low molecular weight heparin delays tendon repair if given continuously, but not if injected intermittently, probably because the anti-factor Xa activity between injections returns to normal, allowing sufficient thrombin stimulation for repair. These findings indicate the need for caution in the assessment of long-acting thrombin and factor Xa inhibitors

Objectives. Re-rupture is common after primary flexor tendon repair. Characterization of the biological changes in the ruptured tendon stumps would be helpful, not only to understand the biological responses to the failed tendon repair, but also to investigate if the tendon stumps could be used as a recycling biomaterial for tendon regeneration in the secondary grafting surgery. Methods. A canine flexor tendon repair and failure model was used. Following six weeks of repair failure, the tendon stumps were analyzed and characterized as isolated tendon-derived stem cells (TDSCs). Results. Failed-repair stump tissue showed cellular accumulation of crumpled and disoriented collagen fibres. Compared with normal tendon, stump tissue had significantly higher gene expression of collagens I and III, matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and insulin-like growth factor (IGF). The stump TDSCs presented both mesenchymal stem and haematopoietic cell markers with significantly increased expression of CD34, CD44, and CD90 markers. Stump TDSCs exhibited similar migration but a lower proliferation rate, as well as similar osteogenic differentiation but a lower chondrogenic/adipogenic differentiation capability, compared with normal TDSCs. Stump TDSCs also showed increasing levels of SRY-box 2 (Sox2), octamer-binding transcription factor 4 (Oct4), tenomodulin (TNMD), and scleraxis (Scx) protein and gene expression. Conclusion. We found that a failed repair stump had increased cellularity that preserved both mesenchymal and haematopoietic stem cell characteristics, with higher collagen synthesis, MMP, and growth factor gene expression. This study provides evidence that tendon stump tissue has regenerative potential. Cite this article: C-C. Lu, T. Zhang, R. L. Reisdorf, P. C. Amadio, K-N. An, S. L. Moran, A. Gingery, C. Zhao. Biological analysis of flexor tendon repair-failure stump tissue: A potential recycling of tissue for tendon regeneration. Bone Joint Res 2019;8:232–245. DOI: 10.1302/2046-3758.86.BJR-2018-0239.R1

We present a system for treatment by controlled motion after repair of flexor tendons in the hand. This Washington regimen incorporates both controlled active extension against passive flexion by rubber band and the use of controlled passive extension and flexion. We utilise the Brooke Army Hospital modification of the rubber band passive flexion splint; this provides for maximal excursion of the tendon with full passive flexion of the finger. The 66 patients (78 fingers) who form the basis of this study all sustained complete laceration of the flexor profundus and superficialis tendons in "no man's land". Results were evaluated by the Strickland formula of total active motion (TAM) of the proximal and distal interphalangeal joints. Sixty-two fingers (80%) were rated "excellent", 14 fingers (18%) were "good", two fingers (2%) were "fair", none was rated "poor". Our regimen of controlled motion rehabilitation has also been applied with equal success to cases of flexor tendon grafting.

Aims

Although absorbable sutures for the repair of acute Achilles tendon rupture (ATR) have been attracting attention, the rationale for their use remains insufficient. This study prospectively compared the outcomes of absorbable and nonabsorbable sutures for the repair of acute ATR.

The effects of splintage, suture and excision of the tendon sheath on the healing of incompletely transected flexor tendons in the rabbit have been evaluated separately and in various combinations. When all procedures were done together, repair was accompanied by dense adhesion formation with little evidence of any healing activity by the tendon cells. The experiments indicated that the adhesions were the result not of any one single factor studied but of all three contributing in varying degrees. Suturing produced the most adhesions but synovial sheath excision and immobilisation also contributed. It is suggested that these factors are also responsible for the adhesions which occur after flexor tendon repair in clinical practice

Incomplete avulsion of the proximal hamstrings can be a severely debilitating injury that causes weakness, pain while sitting and inability to run. The results of the surgical treatment of 23 consecutive patients with such injuries at least two years after surgery are described. The surgery consisted of the repair of the hamstrings directly onto the ischial tuberosity. At review, using a visual analogue scale (VAS, 0 to 100), pain while sitting improved from a mean of 40 (0 to 100) to 64 (0 to 100) (p = 0.024), weakness from a mean of 39 (0 to 90) to 76 (7 to 100) (p = 0.0001) and the ability to run from a mean of 24 (0 to 88) to 64 (0 to 95) (p = 0.0001). According to a VAS, satisfaction was rated at a mean of 81 (0 to 100) and 20 patients (87%) would have the same procedure again. Hamstring strength measured pre- and post-operatively had improved significantly from a mean of 64% (0% to 95%) to 88% (50% to 114%) compared with the normal side.

Most of these patients with symptomatic incomplete hamstring avulsions unresponsive to conservative treatment had an improved outcome after surgical repair.

The April 2023 Wrist & Hand Roundup. 360. looks at: MRI-based classification for acute scaphoid injuries: the OxSMART; Deep learning for detection of scaphoid fractures?; Ulnar shortening osteotomy in adolescents; Cost-utility analysis of thumb carpometacarpal resection arthroplasty; Arthritis of the wrist following scaphoid fracture nonunion; Extensor hood injuries in elite boxers; Risk factors for reoperation after flexor tendon repair; Nonoperative versus operative treatment for displaced finger metacarpal shaft fractures

The February 2023 Knee Roundup. 360. looks at: Machine-learning models: are all complications predictable?; Positive cultures can be safely ignored in revision arthroplasty patients that do not meet the 2018 International Consensus Meeting Criteria; Spinal versus general anaesthesia in contemporary primary total knee arthroplasty; Preoperative pain and early arthritis are associated with poor outcomes in total knee arthroplasty; Risk factors for infection and revision surgery following patellar tendon and quadriceps tendon repairs; Supervised versus unsupervised rehabilitation following total knee arthroplasty; Kinematic alignment has similar outcomes to mechanical alignment: a systematic review and meta-analysis; Lifetime risk of revision after knee arthroplasty influenced by age, sex, and indication; Risk factors for knee osteoarthritis after traumatic knee injury

Tendon is a bradytrophic and hypovascular tissue, hence, healing remains a major challenge. The molecular key events involved in successful repair have to be unravelled to develop novel strategies that reduce the risk of unfavourable outcomes such as non-healing, adhesion formation, and scarring. This review will consider the diverse pathophysiological features of tendon-derived cells that lead to failed healing, including misrouted differentiation (e.g. de- or transdifferentiation) and premature cell senescence, as well as the loss of functional progenitors. Many of these features can be attributed to disturbed cell-extracellular matrix (ECM) or unbalanced soluble mediators involving not only resident tendon cells, but also the cross-talk with immigrating immune cell populations. Unrestrained post-traumatic inflammation could hinder successful healing. Pro-angiogenic mediators trigger hypervascularization and lead to persistence of an immature repair tissue, which does not provide sufficient mechano-competence. Tendon repair tissue needs to achieve an ECM composition, structure, strength, and stiffness that resembles the undamaged highly hierarchically ordered tendon ECM. Adequate mechano-sensation and -transduction by tendon cells orchestrate ECM synthesis, stabilization by cross-linking, and remodelling as a prerequisite for the adaptation to the increased mechanical challenges during healing. Lastly, this review will discuss, from the cell biological point of view, possible optimization strategies for augmenting Achilles tendon (AT) healing outcomes, including adapted mechanostimulation and novel approaches by restraining neoangiogenesis, modifying stem cell niche parameters, tissue engineering, the modulation of the inflammatory cells, and the application of stimulatory factors. Cite this article: Bone Joint Res 2022;11(8):561–574

Aims. Rotator cuff (RC) injuries are characterized by tendon rupture, muscle atrophy, retraction, and fatty infiltration, which increase injury severity and jeopardize adequate tendon repair. Epigenetic drugs, such as histone deacetylase inhibitors (HDACis), possess the capacity to redefine the molecular signature of cells, and they may have the potential to inhibit the transformation of the fibro-adipogenic progenitors (FAPs) within the skeletal muscle into adipocyte-like cells, concurrently enhancing the myogenic potential of the satellite cells. Methods. HDACis were added to FAPs and satellite cell cultures isolated from mice. The HDACi vorinostat was additionally administered into a RC injury animal model. Histological analysis was carried out on the isolated supra- and infraspinatus muscles to assess vorinostat anti-muscle degeneration potential. Results. Vorinostat, a HDACi compound, blocked the adipogenic transformation of muscle-associated FAPs in culture, promoting myogenic progression of the satellite cells. Furthermore, it protected muscle from degeneration after acute RC in mice in the earlier muscle degenerative stage after tenotomy. Conclusion. The HDACi vorinostat may be a candidate to prevent early muscular degeneration after RC injury. Cite this article: Bone Joint Res 2024;13(4):169–183

Aims. The aim of this systematic review and meta-analysis is to evaluate differences in functional outcomes and complications between single- (SI) and double-incision (DI) techniques for the treatment of distal biceps tendon rupture. Methods. A comprehensive search on PubMed, MEDLINE, Scopus, and Cochrane Central databases was conducted to identify studies reporting comparative results of the SI versus the DI approach. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was used for search strategy. Of 606 titles, 13 studies met the inclusion criteria; methodological quality was assessed with the Newcastle-Ottawa scale. Random- and fixed-effects models were used to find differences in outcomes between the two surgical approaches. The range of motion (ROM) and the Disabilities of the Arm, Shoulder and Hand (DASH) scores, as well as neurological and non-neurological complications, were assessed. Results. A total of 2,622 patients were identified. No significant differences in DASH score were detected between the techniques. The SI approach showed significantly greater ROM in flexion (standardized mean difference (SMD) -0.508; 95% confidence interval (CI) -0.904 to -0.112) and pronation (SMD -0.325, 95% CI -0.637 to -0.012). The DI technique was associated with significantly less risk of lateral antebrachial cutaneous nerve damage (odds ratio (OR) 4.239, 95% CI 2.171 to 8.278), but no differences were found for other nerves evaluated. The SI group showed significantly fewer events of heterotopic ossification (OR 0.430, 95% CI 0.226 to 0.816) and a lower reoperation rate (OR 0.503, 95% CI 0.317 to 0.798). Conclusion. No significant differences in functional scores can be expected between the SI and DI approaches after distal biceps tendon repair. The SI approach showed greater flexion and pronation ROM and a lower risk of heterotopic ossification and reoperation. The DI approach was favourable in terms of lower risk of neurological complications. Cite this article: Bone Joint J 2020;102-B(12):1608–1617

The February 2015 Wrist & Hand Roundup360 looks at: Toes, feet, hands and transfers… FCR Tendonitis after Trapeziectomy and suspension, Motion sparing surgery for SLAC/SNAC wrists under the spotlight, Instability following distal radius fractures, Bilateral wrist arthrodesis a good idea?, Sodium Hyaluronate improves hand recovery following flexor tendon repair, Ultrasound treatments for de Quervain’s, Strategies for treating metacarpal neck fractures

The June 2013 Wrist & Hand Roundup. 360 . looks at: whether size is a limitation; cancellous bone grafting in scaphoid nonunion; the Kienböck’s dichotomy; late displacement of the distal radius; flexor slide for finger contracture; aesthetic syndactyly; flexor tendon repair; and fixation of trapeziometacarpal cups

The December 2014 Shoulder & Elbow Roundup. 360 . looks at: cuff tears and plexus injury; . corticosteroids and physiotherapy in SAI; diabetes and elbow arthroplasty; distal biceps tendon repairs; shockwave therapy in frozen shoulder; hydrodilation and steroids for adhesive capsulitis; just what do our patients read?; and what happens to that stable radial head fracture?

We investigated the effect of mitomycin-C on the reduction of the formation of peritendinous fibrous adhesions after tendon repair. In 20 Wistar albino rats the tendo Achillis was cut and repaired using a modified Kessler technique. The rats were divided into two equal groups. In group 1, an injection of mitomycin-C was placed between the tendon and skin of the right leg. In group 2, an identical volume of sterile normal saline was injected on the left side in a similar fashion. All the rats received mitomycin-C or saline for four weeks starting from the day of operation. The animals were killed after 30 days. The formation of peritendinous fibrous tissue, the inflammatory reaction and tendon healing were evaluated. The tensile strength of the repaired tendons was measured biomechanically. Microscopic evidence of the formation of adhesions and inflammation was less in group 1. There was no significant difference in the tensile load required to rupture the repaired tendons in the two groups. Mitomycin-C may therefore provide a simple and inexpensive means of preventing of post-operative adhesions

Rotator cuff tears are common in middle-aged and elderly patients. Despite advances in the surgical repair of rotator cuff tears, the rates of recurrent tear remain high. This may be due to the complexity of the tendons of the rotator cuff, which contributes to an inherently hostile healing environment. During the past 20 years, there has been an increased interest in the use of biologics to complement the healing environment in the shoulder, in order to improve rotator cuff healing and reduce the rate of recurrent tears. The aim of this review is to provide a summary of the current evidence for the use of forms of biological augmentation when repairing rotator cuff tears.

Cite this article: Bone Joint J 2024;106-B(9):978–985.

We tested four types of surgical repair for load to failure and distraction in a bovine model of Achilles tendon repair. A total of 20 fresh bovine Achilles tendons were divided transversely 4 cm proximal to the calcaneal insertion and randomly repaired using the Dresden technique, a Krackow suture, a triple-strand Dresden technique or a modified oblique Dresden technique, all using a Fiberwire suture. Each tendon was loaded to failure. The force applied when a 5 mm gap was formed, peak load to failure, and mechanism of failure were recorded. The resistance to distraction was significantly greater for the triple technique (mean 246.1 N (205 to 309) to initial gapping) than for the Dresden (mean 180 N (152 to 208); p = 0.012) and the Krackow repairs (mean 101 N (78 to 112; p < 0.001). Peak load to failure was significantly greater for the triple-strand repair (mean 675 N (453 to 749)) than for the Dresden (mean 327.8 N (238 to 406); p < 0.001), Krackow (mean 223.6 N (210 to 252); p <  0.001) and oblique repairs (mean 437.2 N (372 to 526); p < 0.001). Failure of the tendon was the mechanism of failure for all specimens except for the tendons sutured using the Krackow technique, where the failure occurred at the knot. The triple-strand technique significantly increased the tensile strength (p = 0.0001) and gap resistance (p = 0.01) of bovine tendon repairs, and might have advantages in human application for accelerated post-operative rehabilitation

We describe three patients in whom the tibial nerve was used, in mistake for the plantaris tendon, to repair a ruptured calcaneal tendon. The tendon repair was successful in all cases, but despite attempted reconstruction of the nerve, no patient had any motor recovery although two regained some protective sensation

The October 2024 Shoulder & Elbow Roundup360 looks at: Proximal humeral fractures with vascular compromise; Outcomes and challenges of revision arthroscopic rotator cuff repair: a systematic review; Evaluating treatment effectiveness for lateral elbow tendinopathy: a systematic review and network meta-analysis; Tendon transfer techniques for irreparable subscapularis tears: a comparative review; Impact of subscapularis repair in reverse shoulder arthroplasty; Isolated subscapularis tears strongly linked to shoulder pseudoparesis; Nexel and Coonrad-Morrey total elbow arthroplasties show comparable revision rates in New Zealand study; 3D MRI matches 3D CT in assessing bone loss and shoulder morphology in dislocation cases.

Aims

A revision for periprosthetic joint infection (PJI) in total hip arthroplasty (THA) has a major effect on the patient’s quality of life, including walking capacity. The objective of this case control study was to investigate the histological and ultrastructural changes to the gluteus medius tendon (GMED) in patients revised due to a PJI, and to compare it with revision THAs without infection performed using the same lateral approach.

Aims

To test the hypothesis that reseeded anterior cruciate ligament (ACL)-derived cells have a better ability to survive and integrate into tendon extracellular matrix (ECM) and accelerate the ligamentization process, compared to adipose-derived mesenchymal stem cells (ADMSCs).

Aims

Posterior malleolar (PM) fractures are commonly associated with ankle fractures, pilon fractures, and to a lesser extent tibial shaft fractures. The tibialis posterior (TP) tendon entrapment is a rare complication associated with PM fractures. If undiagnosed, TP entrapment is associated with complications, ranging from reduced range of ankle movement to instability and pes planus deformities, which require further surgeries including radical treatments such as arthrodesis.

Injuries to the quadriceps muscle group are common in athletes performing high-speed running and kicking sports. The complex anatomy of the rectus femoris puts it at greatest risk of injury. There is variability in prognosis in the literature, with reinjury rates as high as 67% in the severe graded proximal tear. Studies have highlighted that athletes can reinjure after nonoperative management, and some benefit may be derived from surgical repair to restore function and return to sport (RTS). This injury is potentially career-threatening in the elite-level athlete, and we aim to highlight the key recent literature on interventions to restore strength and function to allow early RTS while reducing the risk of injury recurrence. This article reviews the optimal diagnostic strategies and classification of quadriceps injuries. We highlight the unique anatomy of each injury on MRI and the outcomes of both nonoperative and operative treatment, providing an evidence-based management framework for athletes.

Cite this article: Bone Joint J 2023;105-B(12):1244–1251.

The December 2022 Foot & Ankle Roundup³⁶⁰ looks at: Evans calcaneal osteotomy and multiplanar correction in flat foot deformity; Inflammatory biomarkers in tibialis posterior tendon dysfunction; Takedown of ankle fusions and conversion to total ankle arthroplasty; Surgical incision closure with three different materials; Absorbable sutures are not inferior to nonabsorbable sutures for tendo Achilles repair; Zadek’s osteotomy is a reliable technique for treating Haglund’s syndrome; How to best assess patient limitations after acute Achilles tendon injury; Advances in the management of infected nonunion of the foot and ankle.

Aims

Rotator cuff disease (RCD) can considerably decrease quality of life. Here, we investigated whether health-related quality of life (HRQoL) influences the need for surgery in patients with RCD.

The February 2023 Shoulder & Elbow Roundup³⁶⁰ looks at: Arthroscopic capsular release or manipulation under anaesthesia for frozen shoulder?; Distal biceps repair through a single incision?; Distal biceps tendon ruptures: diagnostic strategy through physical examination; Postoperative multimodal opioid-sparing protocol vs standard opioid prescribing after knee or shoulder arthroscopy: a randomized clinical trial; Graft healing is more important than graft technique in massive rotator cuff tear; Subscapularis tenotomy versus peel after anatomic shoulder arthroplasty; Previous rotator cuff repair increases the risk of revision surgery for periprosthetic joint infection after reverse shoulder arthroplasty; Conservative versus operative treatment of acromial and scapular spine fractures following reverse total shoulder arthroplasty.

Operative fixation is the treatment of choice for a rupture of the distal tendon of biceps. A variety of techniques have been described including transosseous sutures and suture anchors. The poor quality of the bone of the radial tuberosity might affect the load to failure of the tendon repair in early rehabilitation. The aim of this study was to determine the loads to failure of different techniques of fixation and to investigate their association with the bone mineral density of the radial tuberosity. Peripheral quantitative computed tomography was carried out to measure the trabecular and cortical bone mineral density of the radial tuberosity in 40 cadaver specimens. The loads to failure in four different techniques of fixation were determined. The Endobutton-based method showed the highest failure load at 270 N (. sd. 22) (p < 0.05). The mean failure load of the transosseous suture technique was 210 N (. sd. 66) and that of the TwinFix-QuickT 5.0 mm was 57 N (. sd. 22), significantly lower than those of all other repairs (p < 0.05). No significant correlation was seen between bone mineral density and loads to failure. The transosseous technique is an easy and cost-saving procedure for fixation of the distal biceps tendon. TwinFix-QuickT 5.0 mm had significantly lower failure loads, which might affect early rehabilitation, particularly in older patients

The October 2023 Wrist & Hand Roundup³⁶⁰ looks at: Distal radius fracture management: surgeon factors markedly influence decision-making; Fracture-dislocation of the radiocarpal joint: bony and capsuloligamentar management, outcomes, and long-term complications; Exploring the role of artificial intelligence chatbot in the management of scaphoid fractures; Role of ultrasonography for evaluation of nerve recovery in repaired median nerve lacerations; Four weeks versus six weeks of immobilization in a cast following closed reduction for displaced distal radial fractures in adult patients: a multicentre randomized controlled trial; Rehabilitation following flexor tendon injury in Zone 2: a randomized controlled study; On the road again: return to driving following minor hand surgery; Open versus single- or dual-portal endoscopic carpal tunnel release: a meta-analysis of randomized controlled trials.

The December 2023 Trauma Roundup³⁶⁰ looks at: Distal femoral arthroplasty: medical risks under the spotlight; Quads repair: tunnels or anchors?; Complex trade-offs in treating severe tibial fractures: limb salvage versus primary amputation; Middle-sized posterior malleolus fractures – to fix?; Bone transport through induced membrane: a randomized controlled trial; Displaced geriatric femoral neck fractures; Risk factors for reoperation to promote union in 1,111 distal femur fractures; New versus old – reliability of the OTA/AO classification for trochanteric hip fractures; Risk factors for fracture-related infection after ankle fracture surgery.

Aims

The primary aim of this study was to assess the feasibility of recruiting and retaining patients to a patient-blinded randomized controlled trial comparing corticosteroid injection (CSI) to autologous protein solution (APS) injection for the treatment of subacromial shoulder pain in a community care setting. The study focused on recruitment rates and retention of participants throughout, and collected data on the interventions’ safety and efficacy.

Rotator cuff pathology is the main cause of shoulder pain and dysfunction in older adults. When a rotator cuff tear involves the subscapularis tendon, the symptoms are usually more severe and the prognosis after surgery must be guarded. Isolated subscapularis tears represent 18% of all rotator cuff tears and arthroscopic repair is a good alternative primary treatment. However, when the tendon is deemed irreparable, tendon transfers are the only option for younger or high-functioning patients. The aim of this review is to describe the indications, biomechanical principles, and outcomes which have been reported for tendon transfers, which are available for the treatment of irreparable subscapularis tears.

The best tendon to be transferred remains controversial. Pectoralis major transfer was described more than 30 years ago to treat patients with failed surgery for instability of the shoulder. It has subsequently been used extensively to manage irreparable subscapularis tendon tears in many clinical settings. Although pectoralis major reproduces the position and orientation of the subscapularis in the coronal plane, its position in the axial plane – anterior to the rib cage – is clearly different and does not allow it to function as an ideal transfer. Consistent relief of pain and moderate recovery of strength and function have been reported following the use of this transfer. In an attempt to improve on these results, latissimus dorsi tendon transfer was proposed as an alternative and the technique has evolved from an open to an arthroscopic procedure. Satisfactory relief of pain and improvements in functional shoulder scores have recently been reported following its use. Both pectoralis minor and upper trapezius transfers have also been used in these patients, but the outcomes that have been reported do not support their widespread use.

Cite this article: Bone Joint J 2024;106-B(9):970–977.

Aims

In the UK, the agricultural, military, and construction sectors have stringent rules about the use of hearing protection due to the risk of noise-induced hearing loss. Orthopaedic staff may also be at risk due to the use of power tools. The UK Health and Safety Executive (HSE) have clear standards as to what are deemed acceptable occupational levels of noise on A-weighted and C-weighted scales. The aims of this review were to assess the current evidence on the testing of exposure to noise in orthopaedic operating theatres to see if it exceeds these regulations.

Aims

This study compared patients who underwent arthroscopic repair of large to massive rotator cuff tears (LMRCTs) with isolated incomplete repair of the tear and patients with incomplete repair with biceps tendon augmentation. We aimed to evaluate the additional benefit on clinical outcomes and the capacity to lower the re-tear rate.

Aims

Favourable short-term outcomes have been reported following latissimus dorsi tendon transfer for patients with an irreparable subscapularis (SSC) tendon tear. The aim of this study was to investigate the long-term outcomes of this transfer in these patients.

We treated surgically 16 shoulders with an isolated traumatic rupture of the subscapularis tendon over a six-year period. Nine patients had a total and seven a partial tear of the subscapularis tendon. Repair was undertaken through a small deltopectoral groove approach. The mean Constant score improved in total tears from 38.7 to 89.3 points (p = 0.003) and in partial tears from 50.7 to 87.9 points (p = 0.008). The total tears were significantly more improved by surgery than the partial tears (p = 0.001). The delay between trauma and surgery was inversely proportional to the improvement in the Constant score suggesting that early diagnosis and surgical repair improves outcome

Aims

This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum.

1. The case notes of 140 patients with a total of 297 severed long flexor tendons in the thumb and fingers have been analysed. 2. Fifty-seven patients in whom tendon reconstructive surgery was performed have been examined and the results have been recorded by three methods. 3. Methods of assessing finger and tendon function are reviewed and discussed. Accuracy and precision in tendon repair should be followed by an accurate and precise evaluation of tendon, joint and finger function. 4. A method of assessing the function is described. This is expressed as a percentage of the function of the uninjured contralateral finger

We examined the structure of the digital flexor sheath by dissection and histology. The inner aspect of the sheath was found not to be a continuous smooth surface, as depicted in anatomical and surgical texts. The thin parts of the sheath often overlapped the pulleys before attaching to their superficial aspects, so that the pulleys possessed free edges within the sheath. The frequency of occurrence and sizes of these overlaps were studied in 48 cadaveric fingers; the largest and most frequent overlap was at the distal end of the A2 pulley. Functional studies showed an intricate mechanism of pulley approximation and sheath bulging during flexion. Sutured or partly cut tendons triggered on the free edges; this could be a major contributor to the failures of tendon repairs in "no man's land"

We have investigated the effects of the intra-operative application of a combination of hyaluronic acid and amniotic membrane on adhesions in the flexor tendons of a chicken model. We used 144 tendons which were partially divided and then repaired by a modified Kessler technique. There were four test groups: group 1, simple tendon repair, group 2, repair site wrapped with amniotic membrane, group 3, hyaluronic acid injected around the repair site, and group 4, repair site wrapped with amniotic membrane and hyaluronic acid injected within it. At three and six weeks, the extent of the adhesions and the healing of the tendon were evaluated macroscopically and histologically. The range of movement of the toe and tensile strength of the repaired tendons were measured at 20 weeks. The least adhesions were observed in group 4 but no significant difference was found in the healing of the tendons. Overall, the intra-operative application of a combination of hyaluronic acid and amniotic membrane appears to be effective in preventing adhesions of the flexor tendon

We split 100 porcine flexor tendons into five groups of 20 tendons for repair. Three groups were repaired using the Pennington modified Kessler technique, the cruciate or the Savage technique, one using one new device per tendon and the other with two new devices per tendon. Half of the tendons received supplemental circumferential Silfverskiöld type B cross-stitch. The repairs were loaded to failure and a record made of their bulk, the force required to produce a 3 mm gap, the maximum force applied before failure and the stiffness. When only one device was used repairs were equivalent to the Pennington modified Kessler for all parameters except the force to produce a 3 mm gap when supplemented with a circumferential repair, which was equivalent to the cruciate. When two devices were used the repair strength was equivalent to the cruciate repair, and when the two-device repair was supplemented with a circumferential suture the force to produce a 3 mm gap was equivalent to that of the Savage six-strand technique

1. Multiple barbed sutures made from nylon are described and the theoretical advantages with the use of the nylon are outlined. 2. Methods of joining tendon stumps using the multiple barbed sutures are illustrated and in vitro tests show that the anchorage of this suture in cadaveric and canine flexor tendons is of the same order. 3. Preliminary in vivo tests where the flexor digitorum profundus tendon of dogs have been repaired with multiple barbed sutures show that it maintains apposition of the tendon stump as effectively as the Bunnell "buried core" technique using G 40 stainless steel wire. 4. The multiple barbed suture is an experimental suture for certain compact tendons capable of giving a neat and relatively atraumatic junction. It requires further study and development. It does not appear to make tendon repair technically easier, nor does it alter the indications for operation or management

Aims

Stemless humeral implants have been developed to overcome stem-related complications in total shoulder arthroplasty (TSA). However, stemless implant designs may hypothetically result in less stable initial fixation, potentially affecting long-term survival. The aim of this study is to investigate early fixation and migration patterns of the stemless humeral component of the Simpliciti Shoulder System and to evaluate clinical outcomes.

Aims

The use and variety of stemless humeral components in anatomical total shoulder arthroplasty (TSA) have proliferated since their advent in 2004. Early outcomes are reassuring but independent mid-term results are scarce. This independent study reports a consecutive series of 143 Eclipse stemless shoulder prostheses with a minimum five-year (5 to 10) follow-up.

Aims

The aim of this study is to provide a detailed description of cases combining bridging patch repair with artificial ligament “internal brace” reinforcement to treat irreparable massive rotator cuff tears, and report the preliminary results.

Aims

We aim to objectively assess the impact of COVID-19 on mean total operative cases for all indicative procedures (as outlined by the Joint Committee on Surgical Training (JCST)) experienced by orthopaedic trainees in the deanery of the Republic of Ireland. Subjective experiences were reported for each trainee using questionnaires.

Aims

Rotator cuff (RC) tears are common musculoskeletal injuries which often require surgical intervention. Noninvasive pulsed electromagnetic field (PEMF) devices have been approved for treatment of long-bone fracture nonunions and as an adjunct to lumbar and cervical spine fusion surgery. This study aimed to assess the effect of continuous PEMF on postoperative RC healing in a rat RC repair model.

Aims

The aim of this study was to evaluate the need for hand trauma services during the COVID-19 pandemic lockdown, specifically related to surgical requirements. This will provide useful information for planning and resource allocation in the event of any further lockdown.

Aims

Despite recent advances in arthroscopic rotator cuff repair, re-tear rates remain high. New methods to improve healing rates following rotator cuff repair must be sought. Our primary objective was to determine if adjunctive bone marrow stimulation with channelling five to seven days prior to arthroscopic cuff repair would lead to higher Western Ontario Rotator Cuff (WORC) scores at 24 months postoperatively compared with no channelling.

Aims

Reverse total shoulder arthroplasty (RTSA) using trabecular metal (TM)-backed glenoid implants has been introduced with the aim to increase implant survival. Only short-term reports on the outcomes of TM-RTSA have been published to date. We aim to present the seven-year survival of TM-backed glenoid implants along with minimum five-year clinical and radiological outcomes.

Aims

Existing literature indicates that inferiorly inclined glenoid baseplates following reverse total shoulder arthroplasty (RSA) produce better outcomes compared to superiorly inclined baseplates. We aim to compare clinical outcomes for RSAs with superiorly and neutrally/inferiorly inclined lateralized glenospheres.

The COVID-19 pandemic has disrupted all segments of daily life, with the healthcare sector being at the forefront of this upheaval. Unprecedented efforts have been taken worldwide to curb this ongoing global catastrophe that has already resulted in many fatalities. One of the areas that has received little attention amid this turmoil is the disruption to trainee education, particularly in specialties that involve acquisition of procedural skills. Hand surgery in Singapore is a standalone combined programme that relies heavily on dedicated cross-hospital rotations, an extensive didactic curriculum and supervised hands-on training of increasing complexity. All aspects of this training programme have been affected because of the cancellation of elective surgical procedures, suspension of cross-hospital rotations, redeployment of residents, and an unsustainable duty roster. There is a real concern that trainees will not be able to meet their training requirements and suffer serious issues like burnout and depression. The long-term impact of suspending training indefinitely is a severe disruption of essential medical services. This article examines the impact of a global pandemic on trainee education in a demanding surgical speciality. We have outlined strategies to maintain trainee competencies based on the following considerations: 1) the safety and wellbeing of trainees is paramount; 2) resource utilization must be thoroughly rationalized; 3) technology and innovative learning methods must supplant traditional teaching methods; and 4) the changes implemented must be sustainable. We hope that these lessons will be valuable to other training programs struggling to deliver quality education to their trainees, even as we work together to battle this global catastrophe.

Aims

COVID-19 remains the major focus of healthcare provision. Managing orthopaedic emergencies effectively, while at the same time protecting patients and staff, remains a challenge. We explore how the UK lockdown affected the rate, distribution, and type of orthopaedic emergency department (ED) presentations, using the same period in 2019 as reference. This article discusses considerations for the ED and trauma wards to help to maintain the safety of patients and healthcare providers with an emphasis on more remote geography.

Deep gluteal syndrome is an increasingly recognized disease entity, caused by compression of the sciatic or pudendal nerve due to non-discogenic pelvic lesions. It includes the piriformis syndrome, the gemelli-obturator internus syndrome, the ischiofemoral impingement syndrome, and the proximal hamstring syndrome. The concept of the deep gluteal syndrome extends our understanding of posterior hip pain due to nerve entrapment beyond the traditional model of the piriformis syndrome. Nevertheless, there has been terminological confusion and the deep gluteal syndrome has often been undiagnosed or mistaken for other conditions. Careful history-taking, a physical examination including provocation tests, an electrodiagnostic study, and imaging are necessary for an accurate diagnosis.

After excluding spinal lesions, MRI scans of the pelvis are helpful in diagnosing deep gluteal syndrome and identifying pathological conditions entrapping the nerves. It can be conservatively treated with multidisciplinary treatment including rest, the avoidance of provoking activities, medication, injections, and physiotherapy.

Endoscopic or open surgical decompression is recommended in patients with persistent or recurrent symptoms after conservative treatment or in those who may have masses compressing the sciatic nerve.

Many physicians remain unfamiliar with this syndrome and there is a lack of relevant literature. This comprehensive review aims to provide the latest information about the epidemiology, aetiology, pathology, clinical features, diagnosis, and treatment.

Cite this article: Bone Joint J 2020;102-B(5):556–567.

Injuries to the hamstring muscle complex are common in athletes, accounting for between 12% and 26% of all injuries sustained during sporting activities. Acute hamstring injuries often occur during sports that involve repetitive kicking or high-speed sprinting, such as American football, soccer, rugby, and athletics. They are also common in watersports, including waterskiing and surfing. Hamstring injuries can be career-threatening in elite athletes and are associated with an estimated risk of recurrence in between 14% and 63% of patients. The variability in prognosis and treatment of the different injury patterns highlights the importance of prompt diagnosis with magnetic resonance imaging (MRI) in order to classify injuries accurately and plan the appropriate management.

Low-grade hamstring injuries may be treated with nonoperative measures including pain relief, eccentric lengthening exercises, and a graduated return to sport-specific activities. Nonoperative management is associated with highly variable times for convalescence and return to a pre-injury level of sporting function. Nonoperative management of high-grade hamstring injuries is associated with poor return to baseline function, residual muscle weakness and a high-risk of recurrence. Proximal hamstring avulsion injuries, high-grade musculotendinous tears, and chronic injuries with persistent weakness or functional compromise require surgical repair to enable return to a pre-injury level of sporting function and minimize the risk of recurrent injury.

This article reviews the optimal diagnostic imaging methods and common classification systems used to guide the treatment of hamstring injuries. In addition, the indications and outcomes for both nonoperative and operative treatment are analyzed to provide an evidence-based management framework for these patients.

Cite this article: Bone Joint J 2020;102-B(10):1281–1288.

Aims

In the context of tendon degenerative disorders, the need for innovative conservative treatments that can improve the intrinsic healing potential of tendon tissue is progressively increasing. In this study, the role of pulsed electromagnetic fields (PEMFs) in improving the tendon healing process was evaluated in a rat model of collagenase-induced Achilles tendinopathy.

Aims

The aim of this study is to determine the effects of the UK lockdown during the COVID-19 pandemic on the orthopaedic admissions, operations, training opportunities, and theatre efficiency in a large district general hospital.

Aims

Despite the increase in the surgical repair of proximal hamstring tears, there exists a lack of consensus in the optimal timing for surgery. There is also disagreement on how partial tears managed surgically compare with complete tears repaired surgically. This study aims to compare the mid-term functional outcomes in, and operating time required for, complete and partial proximal hamstring avulsions, that are repaired both acutely and chronically.

Aims

The aim was to compare long-term patient-reported outcome measures (PROMs) after operative and nonoperative treatment of acute Achilles tendon rupture in the context of a randomized controlled trial.

Aims

Elective surgery has been severely curtailed as a result of the COVID-19 pandemic. There is little evidence to guide surgeons in assessing what processes should be put in place to restart elective surgery safely in a time of endemic COVID-19 in the community.

Aims

Many biomechanical studies have shown that the weakest biomechanical point of a rotator cuff repair is the suture-tendon interface at the medial row. We developed a novel double rip-stop (DRS) technique to enhance the strength at the medial row for rotator cuff repair. The objective of this study was to evaluate the biomechanical properties of the DRS technique with the conventional suture-bridge (SB) technique and to evaluate the biomechanical performance of the DRS technique with medial row knots.

Aims

The first death in the UK caused by COVID-19 occurred on 5 March 2020. We aim to describe the clinical characteristics and outcomes of major trauma and orthopaedic patients admitted in the early COVID-19 era.

Aims

The consensus is that bipolar hemiarthroplasty (BHA) in allograft-prosthesis composite (APC) reconstruction of the proximal femur following primary tumour resection provides more stability than total hip arthroplasty (THA). However, no comparative study has been performed. In this study, we have compared the outcome and complication rates of these two methods.

Aims. Failure of healing is a well-known problem after repair of the rotator cuff. This study aimed to investigate if early repair of trauma-related full-thickness rotator cuff tears (FTRCTs) could prevent this failure. Patients and Methods. In this prospective trial, 62 consecutive patients (14 women (23%), 48 men (77%); median age 61 years (interquartile range (IQR) 54 to 65)) with trauma-related FTRCT underwent arthroscopic single-row repair within six weeks of trauma. Tendon integrity was assessed one year after surgery using the Sugaya score on MR images. Patients were followed up with Western Ontario Rotator Cuff (WORC) index, EuroQol visual analogue scale (EQ VAS), and the Constant–Murley score (CS) two years after repair. Results. A total of 57 patients (92%) had MR images available at one year; 59 patients (95%) had CS (one year), WORC (two years), and EQ VAS scores (two years). Intact repair was found on MRI in 36 patients (63%); 13 patients (23%) displayed healing failure of at least one repaired tendon and eight patients (14%) displayed total healing failure. Median WORC index and relative CS improved from 30.8 points (IQR 20.1 to 38.6) at baseline to 85.0 points (IQR 60.6 to 95.7) at two years and 26.5 points (IQR 21.2 to 37.4) to 83.2 points (IQR 71.9 to 97.5) at one year, respectively. The relative CS at one year was significantly better among those with intact repairs compared with those with healing failure (91.6 vs 78.1 points; p = 0.031). Conclusion. Although early repair of trauma-related FTRCT improved patient relevant outcomes over two years for the entire cohort, only two out of three repaired rotator cuffs displayed intact structural integrity on MRI after one year. Consequently, early repair did not seem to prevent healing failure after trauma-related FTRCT. Cite this article: Bone Joint J 2019;101-B:603–609

Objectives

Platelet-rich fibrin matrix (PRFM) has been proved to enhance tenocyte proliferation but has mixed results when used during rotator cuff repair. The optimal PRFM preparation protocol should be determined before clinical application. To screen the best PRFM to each individual’s tenocytes effectively, small-diameter culture wells should be used to increase variables. The gelling effect of PRFM will occur when small-diameter culture wells are used. A co-culture device should be designed to avoid this effect.

Objectives. Recently, the field of tissue engineering has made numerous advances towards achieving artificial tendon substitutes with excellent mechanical and histological properties, and has had some promising experimental results. The purpose of this systematic review is to assess the efficacy of tissue engineering in the treatment of tendon injuries. Methods. We searched MEDLINE, Embase, and the Cochrane Library for the time period 1999 to 2016 for trials investigating tissue engineering used to improve tendon healing in animal models. The studies were screened for inclusion based on randomization, controls, and reported measurable outcomes. The RevMan software package was used for the meta-analysis. Results. A total of 388 references were retrieved and 35 studies were included in this systematic review. The different biomaterials developed were analyzed and we found that they improve the biomechanical and histological characteristics of the repaired tendon. At meta-analysis, despite a high heterogeneity, it revealed a statistically significant effect in favour of the maximum load, the maximum stress, and the Young’s modulus between experimental and control groups. In the forest plot, the diamond was on the right side of the vertical line and did not intersect with the line, favouring experimental groups. Conclusions. This review of the literature demonstrates the heterogeneity in the tendon tissue engineering literature. Several biomaterials have been developed and have been shown to enhance tendon healing and regeneration with improved outcomes. Cite this article: D. González-Quevedo, I. Martínez-Medina, A. Campos, F. Campos, V. Carriel. Tissue engineering strategies for the treatment of tendon injuries: a systematic review and meta-analysis of animal models. Bone Joint Res 2018;7:318–324. DOI: 10.1302/2046-3758.74.BJR-2017-0326

Objectives

Platelet-rich plasma (PRP) is being used increasingly often in the clinical setting to treat tendon-related pathologies. Yet the optimal PRP preparations to promote tendon healing in different patient populations are poorly defined. Here, we sought to determine whether increasing the concentration of platelet-derived proteins within a derivative of PRP, platelet lysate (PL), enhances tenocyte proliferation and migration in vitro, and whether the mitogenic properties of PL change with donor age.

Aims

We analyzed the long-term outcomes of patients observed over ten years after resection en bloc and reconstruction with extracorporeal irradiated autografts

Objectives

The incidence of acute Achilles tendon rupture appears to be increasing. The aim of this study was to summarize various therapies for acute Achilles tendon rupture and discuss their relative merits.

Aims

The aims of this study were to assess the exposure and preservation of the abductor mechanism during primary total hip arthroplasty (THA) using the posterior approach, and to evaluate gluteus maximus transfer to restore abductor function of chronically avulsed gluteus medius and minimus.

Aims

The aim of the study was to analyze the results of primary tendon reinsertion in acute and chronic distal triceps tendon ruptures (DTTRs) in the general population.

Tendinopathy is a debilitating musculoskeletal condition which can cause significant pain and lead to complete rupture of the tendon, which often requires surgical repair. Due in part to the large spectrum of tendon pathologies, these disorders continue to be a clinical challenge. Animal models are often used in this field of research as they offer an attractive framework to examine the cascade of processes that occur throughout both tendon pathology and repair. This review discusses the structural, mechanical, and biological changes that occur throughout tendon pathology in animal models, as well as strategies for the improvement of tendon healing.

Cite this article: Bone Joint Res 2014;3:193–202.

Objectives

The present study describes a novel technique for revitalising allogenic intrasynovial tendons by combining cell-based therapy and mechanical stimulation in an ex vivo canine model.

Aims

Our purpose was to determine the quality of current randomised controlled trials (RCTs) in hand surgery using standardised metrics.

The April 2014 Wrist & Hand Roundup³⁶⁰ looks at: diagnosis of compressive neuropathy; relevant reviews; the biomechanics of dorsal PIP fracture dislocation; the more strands the better; and state of mind the best predictor of outcome.

Objectives

All-suture anchors are increasingly used in rotator cuff repair procedures. Potential benefits include decreased bone damage. However, there is limited published evidence for the relative strength of fixation for all-suture anchors compared with traditional anchors.

Objectives

Emerging evidence indicates that tendon disease is an active process with inflammation that is critical to disease onset and progression. However, the key cytokines responsible for driving and sustaining inflammation have not been identified.

Objectives

Although many clinical and experimental investigations have shed light on muscle atrophy and intramuscular accumulation of fat after rotator cuff disruption, none have reported on their onset in the absence of muscle retraction.

In order to compare the outcome from surgical repair and physiotherapy, 103 patients with symptomatic small and medium-sized tears of the rotator cuff were randomly allocated to one of the two approaches. The primary outcome measure was the Constant score, and secondary outcome measures included the self-report section of the American Shoulder and Elbow Surgeons score, the Short Form 36 Health Survey and subscores for shoulder movement, pain, strength and patient satisfaction. Scores were taken at baseline and after six and 12 months by a blinded assessor. Nine patients (18%) with insufficient benefit from physiotherapy after at least 15 treatment sessions underwent secondary surgical treatment.

Analysis of between-group differences showed better results for the surgery group on the Constant scale (difference 13.0 points, p − 0.002), on the American Shoulder and Elbow surgeons scale (difference 16.1 points, p < 0.0005), for pain-free abduction (difference 28.8°, p = 0.003) and for reduction in pain (difference on a visual analogue scale −1.7 cm, p < 0.0005).

We compared the bulking and tensile strength of the Pennington modified Kessler, Cruciate and the Savage repairs in an ex vivo model. A total of 60 porcine tendons were randomised to three groups, half repaired using a core suture alone and the remainder employing a core and peripheral technique. The tendons were distracted to failure. The force required to produce a 3 mm gap, the ultimate strength, the mode of failure and bulking for each repair were assessed. We found that there was a significant increase in strength without an increase in bulk as the number of strands increased. The Cruciate repair was significantly more likely to fail by suture pullout than the Pennington modified Kessler or Savage repairs. We advise the use of the Savage repair, especially in the thumb, and a Cruciate when a Savage is not possible. The Pennington modified Kessler repair should be reserved for multiple tendon injuries.

Objectives. Rotator cuff tears are among the most frequent upper extremity injuries. Current treatment strategies do not address the poor quality of the muscle and tendon following chronic rotator cuff tears. Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor that activates many genes that are important in skeletal muscle regeneration. HIF-1α is inhibited under normal physiological conditions by the HIF prolyl 4-hydroxylases (PHDs). In this study, we used a pharmacological PHD inhibitor, GSK1120360A, to enhance the activity of HIF-1α following the repair of a chronic cuff tear, and measured muscle fibre contractility, fibrosis, gene expression, and enthesis mechanics. Methods. Chronic supraspinatus tears were induced in adult rats, and repaired 28 days later. Rats received 0 mg/kg, 3 mg/kg, or 10 mg/kg GSK1120360A daily. Collagen content, contractility, fibre type distribution and size, the expression of genes involved in fibrosis, lipid accumulation, atrophy and inflammation, and the mechanical properties of the enthesis were then assessed two weeks following surgical repair. Results. At two weeks following repair, treatment groups showed increased muscle mass but there was a 15% decrease in force production in the 10 mg/kg group from controls, and no difference between the 0 mg/kg and the 3 mg/kg groups. There was a decrease in the expression of several gene transcripts related to matrix accumulation and fibrosis, and a 50% decrease in collagen content in both treated groups compared with controls. Additionally, the expression of inflammatory genes was reduced in the treated groups compared with controls. Finally, PHD inhibition improved the maximum stress and displacement to failure in repaired tendons. Conclusions. GSK1120360A resulted in improved enthesis mechanics with variable effects on muscle function. PHD inhibition may be beneficial for connective tissue injuries in which muscle atrophy has not occurred. Cite this article: J. P. Gumucio, M. D. Flood, A. Bedi, H. F. Kramer, A. J. Russell, C. L. Mendias. Inhibition of prolyl 4-hydroxylase decreases muscle fibrosis following chronic rotator cuff tear. Bone Joint Res 2017;6:57–65. DOI: 10.1302/2046-3758.61.BJR-2016-0232.R1