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.

Aims. The gold standard for percutaneous Achilles tendon tenotomy during the Ponseti treatment for idiopathic clubfoot is a tenotomy with a No. 15 blade. This trial aims to establish the technique where the tenotomy is performed with a large-bore needle as noninferior to the gold standard. Methods. We randomized feet from children aged below 36 months with idiopathic clubfoot on a 1:1 basis in either the blade or needle group. Follow-up was conducted at three weeks and three months postoperatively, where dorsiflexion range, Pirani scores, and complications were recorded. The noninferiority margin was set at 4° difference in dorsiflexion range at three months postoperatively. Results. The blade group had more dorsiflexion at both follow-up consultations: 18.36° versus 18.03° (p = 0.115) at three weeks and 18.96° versus 18.26° (p = 0.001) at three months. The difference of the mean at three months 0.7° is well below the noninferiority margin of 4°. There was no significant difference in Pirani scores. The blade group had more extensive scar marks at three months than the needle group (8 vs 2). No major complications were recorded. Conclusion. The needle tenotomy is noninferior to the blade tenotomy for usage in Ponseti treatment for idiopathic clubfoot in children aged below 36 months. Cite this article: Bone Joint J 2024;106-B(8):871–878

Aims. Achilles tendon re-rupture (ATRR) poses a significant risk of postoperative complication, even after a successful initial surgical repair. This study aimed to identify risk factors associated with Achilles tendon re-rupture following operative fixation. Methods. This retrospective cohort study analyzed a total of 43,287 patients from national health claims data spanning 2008 to 2018, focusing on patients who underwent surgical treatment for primary Achilles tendon rupture. Short-term ATRR was defined as cases that required revision surgery occurring between six weeks and one year after the initial surgical repair, while omitting cases with simultaneous infection or skin necrosis. Variables such as age, sex, the presence of Achilles tendinopathy, and comorbidities were systematically collected for the analysis. We employed multivariate stepwise logistic regression to identify potential risk factors associated with short-term ATRR. Results. From 2009 to 2018, the short-term re-rupture rate for Achilles tendon surgeries was 2.14%. Risk factors included male sex, younger age, and the presence of Achilles tendinopathy. Conclusion. This large-scale, big-data study reaffirmed known risk factors for short-term Achilles tendon re-rupture, specifically identifying male sex and younger age. Moreover, this study discovered that a prior history of Achilles tendinopathy emerges as an independent risk factor for re-rupture, even following initial operative fixation. Cite this article: Bone Joint Res 2024;13(7):315–320

Insertional Achilles tendinitis with considerable degeneration that failed non-operative treatment typically requires tendon debridement and reattachment to bone. It is common practice for tendons to be reattached back with anchor sutures, but this poses a challenge to patients who are not able to afford them. Bony anchorage of tendons may be performed by passing sutures through tunnels, but the strength of repair compared to by using anchors is not known. We investigated the load at clinical and catastrophic failure of these two methods of reattachment. Sixteen paired Achilles tendons along with the calcaneus were harvested from eight fresh frozen cadavers. Paired randomization was done. For the anchor suture group, two 5’0 anchors with polyethylene #2 sutures were used for reattachment whereas for the suture only group, tendons were reattached to bone using braided polyester #2 sutures via two bony tunnels. All samples were mounted on a materials testing system and preloaded at 50N for 60sec before load to failure at a rate of 1mm/sec. With the assumption that preloading has removed tendon crimp and any subsequent extension is a result of gapping at the repair site, loads at 5mm, 10mm, 15mm, and 20mm of extension were noted as well as the maximal load at failure. We found higher loads were needed to cause an extension of 5 to 20mm in the suture only group compared to the anchor suture group but these data were not significant. On the other hand, the anchor suture group required higher loads before catastrophic failure occurred compared to the suture only group, but this again is not significant. We conclude that suture only reattachment of the Achilles tendon is comparable in strength with anchor suture reattachment, and this method of reattachment can be considered for patients who do not have access to anchor sutures

Aim. Our collaborative study aims to demonstrate that acute partial Achilles Tendon Tears (ATTs) are not separate diagnostic entities from full ATTs. and should be thought of as a continuum rather than binary partial or full. Methods. We pooled anonymised data from four hospitals, identifying patients with acute partial ATTs on USS reports from 2019–2021. Patients were only included if they had an acute injury and no previous background Achilles tendinopathy. Results. 91 patients had acute partial ATTs reported on USS. 74/91 (81%) of patients had clinical findings in keeping with a full ATT (positive Simmonds test, palpable gap). 88/91 (97%) of patients were managed according to local full ATT protocols. 2 patients had MRIs – one showed no tear, the other showed a full rupture. 2 patients underwent surgical repair and both intra-operatively were found to have full ATTs. Conclusion. Our regional data suggests that a significant proportion (81%) of USS diagnosed partial ATTs may in fact be misdiagnosed full ATTs. All injuries clinically suspicious for an ATT should be managed according to local Achilles Protocol. USS is useful to diagnose the presence or absence of a tear but is not good at differentiating partial vs full tear. There is significant tendon end fibrillation and overlap on USS of an acute full ATT, which can give the impression of a partial ATT. More research is needed into whether any threshold exists to support the current distinction of “partial” and “full” as relates to management and outcomes

Background. Neglected clubfoot in this series is defined as untreated equino-cavo-adducto-varus in older children, or adults. Relapsed clubfoot is the residual deformity that remains after single or multiple surgical interventions. Severe neglected clubfoot rarely exists today in developed countries, except in some emigrants from low- and middle-income countries. Acute surgical management with corrective mid-foot osteotomy and elongation of the Achilles tendon has excellent functional outcome. Objective. To assess the functional outcome of acute correction of neglected Talipes-quino-varus deformity in adults. Methods. This is cross sectional, hospital–based study that took place in Khartoum, Sudan. Forty patients were included in this study. Midfoot osteotomy and elongation of the Achilles tendon were performed to all patients. Data was collected using a questionnaire and the functional outcome has been assessed using the American Orthopaedic Foot and Ankle Society Score (AOFAS). This score was measured before surgery and one years after surgery. Results. The mean age was 19.9±4.7 years. Males were 25 (62.5%) and females were 15 (37.5%). The mean preoperative AOFAS score was 37.7±7.1 (poor). This score improved to 80.7±13.7 (good to excellent), two years after surgery. However, this indicates significant change in the functional outcome after the operation (P value < 0.05). Excellent post-operative functional outcome was found among patients aged 18 – 23 years 18 (50%) P. value: 0.021. The majority of patients 36(90%) were fully satisfied with the operation, 2(5%) partially satisfied and 2(5%) were unsatisfied. Conclusion. Acute correction of neglected and relapsed TEV with elongation of the Achilles tendon and single midfoot osteotomy has excellent functional outcome as assessed by AOFAS Score. The satisfaction with this procedure is impressive. The younger age population showed better outcomes with this procedure

Introduction. Tibial nerve anatomy has not been studied profoundly in comparison to Tarsal Tunnel Syndrome (TTS). Assuming symptoms are caused by an anatomical variant or mechanical cause regarding the tibial nerve, it is essential to investigate the anatomy of this structure taking in consideration that surgical and conservative treatments have shown poor results. Methods. 40 lower-leg specimens were obtained. Dissection started 20 centimeters proximal to the Dellon-McKinnon (DM) line towards the medial aspect of the naviculo-cuneiform joint distally. Anteriorly, dissection began at the tibio-talar medial gutter until the medial aspect of the Achilles tendon posteriorly. The plantar aspect extended from medial to lateral within the parameters previously described, ending at the level of the second metatarsal. Results. The flexor retinaculum had a denser consistency in 22.5% of the cases and the average length was 51.9 mm. The flexor retinaculum as an independent structure was found absent and 77.2% of cases as undistinguished extension of the crural fascia. The lateral plantar nerver (LPN) and abductor digiti minimi (ADM) nerve shared same origin in 80% of cases, 34.5% bifurcated proximal to the DM line, 31.2% distally and 34.3% at the same level. The medial calcaneal nerve (MCN) emerged proximal to the DM line in 100% of specimens. The medial plantar nerve (MPN) has its origin proximal to the DM line in 95% of cases. Conclusion. The flexor retinaculum is an extension of the crural fascia and not an independent structure. The LPN and ADM have the same origin in most cases and this presents as an important finding that must be studied in detail for clinical correlations between the motor and sensatory affections of the ADM and LPN respectively. Finally, the branches of the MCN and MPN are the most constant in their distribution and proximal origin in relation to the Dellon-McKinnon line

The June 2024 Foot & Ankle Roundup. 360. looks at: First MTPJ fusion in young versus old patients; Minimally invasive calcaneum Zadek osteotomy and the effect of sequential burr passes; Comparison between Achilles tendon reinsertion and dorsal closing wedge calcaneal osteotomy for the treatment of insertional Achilles tendinopathy; Revision ankle arthroplasty – is it worthwhile?; Tibiotalocalcaneal arthrodesis or below-knee amputation – salvage or sacrifice?; Fusion or replacement for hallux rigidus?

Background. Treatment of arthrogrypotic clubfoot (AC) presents a challenging problem. Over time many different methods have been proposed, with variable rates of success, recurrence and other complications. In this study we describe our 20-year experience in treatment of AC. Materials and methods. Between 1996 and 2016, 165 AC in 90 children (51 males and 39 females) were treated in our department. Their mean age was 7.6 years (3 months-16 years). Ponseti casting and Achilles tendon release (PCATR) was performed on 38 children (68 feet) and soft tissue release and casting (STRC) on 35 children (67 feet). The remaining 17 children (30 feet) underwent wide soft tissue release and correction using the Ilizarov method (STRIL). The results of each subgroup were graded according to clinical (pain, foot appearance, residual deformities, walking and standing status and shoe modifications) and radiological (anteroposterior and lateral talocalcanear angles, the angle between longitudinal axes of talus and the first metatarsal and the position of talus in the lateral view) criteria. Results. The average follow up was 6.4 (2–10) years. Results were excellent (plantigrade, painless, properly loaded feet, without deformities, adapted to common shoes) in 56 PCATR group feet, 59 STRC group feet and 23 STRIL group feet. Good results (required orthopaedic shoes) were obtained in 10 PCATR group feet, 6 STRC group feet and 7 STRIL group feet. Fair results (residual temporary pain and/or mild deformity) presented 2 PCATR group feet and 1 STRC group foot, while bad results (reoccurrence of clubfoot) were found in 1 STRC group foot. Conclusions. On the basis of our 20-year clinical experience we believe that pediatric AC can be successfully treated with PCATR in the age of less than 1 year old (y.o), with STRC between 1–5 y.o. and with STRIL in children over the age of 5 y.o

Early identification of patients at risk for impaired tendon healing and corresponding novel therapeutic approaches are urgent medical needs. This study aimed to clarify the role of CD3+ T-cells during acute Achilles tendon (AT) healing. Blood and hematoma aspirate were taken from 26 patients during AT reconstruction, and additional blood samples were obtained during clinical follow-up at 6, 26 and 52 weeks after surgery. T-cell subsets were analyzed by flow cytometry using CD3, CD4, CD8, CD11a, CD57 and CD28 antibodies. Clinical follow-up included functional tests, MRI assessments, and subjective questionnaires. In vitro, the functional behavior of patient-derived tenocytes was investigated in co-cultures with autologous unpolarized CD4+ or CD8+ T-cells, or IFNy-polarized CD8+ or IL17-polarized CD4+ Tcells (n=5-6). This included alterations in gene expression (qPCR), MMP secretion (ELISA), migration rate (scratch wound healing assay) or contractility (collagen gels). Analysis revealed that elevated CD4+ T-cell levels and reduced CD8+ T-cell levels (increased CD4/CD8 ratio) in hematoma aspirate and pre-operative blood were associated with inferior clinical outcomes regarding pain and function at 26 and 52 weeks. Increased levels of CD8+ -memory T-cell subpopulations in blood 6 weeks after surgery were associated with less tendon elongation. In vitro, tenocytes showed increased MMP1/2/3 levels and collagen III/I ratio in co-culture with unpolarized and/or IL17-polarized CD4+ T-cells compared to unpolarized CD8+ T-cells. This coincided with increased IL17 receptor expression in tenocytes co-cultured with CD4+ T-cells. Exposure of tenocytes to IL17-polarized CD4+ T-cells decreased their migration rate and increased their matrix contractility, especially compared to IFNy-polarized CD8+ T-cells. The CD4+ /CD8+ T-cell ratio could serve as prognostic marker for early identification of patients with impaired AT healing potential. Local reduction of CD4+ T-cell levels or their IL17 secretion represent a potential therapeutic approach to improve AT healing and to prevent weakening of the tendon ECM

Achilles tendon mechanical properties depend on a complex hierarchical design, with collagen being the smallest load-bearing unit. At the nanoscale, collagen molecules are organized into fibrils, which at the microscale are assembled into fibers, followed by larger structures such as sub-tendons or fascicles. Degree of in vivo loading affects the collagen content, and organization and consequently the tissue's mechanical response. We aim to unravel how composition, structural organization, and mechanical response are affected by degree of in vivo loading at each length scale. The presentation will outline the results to date about to the use of high-resolution synchrotron-based tissue characterisation methods on several length scales in combination with in situ mechanical tests. We use a rat model, where the tendons are subjected to varying loading in vivo. To characterize the tissue microstructure, phase-contrast enhanced synchrotron micro-tomography is performed. The 3D fiber organization in fully loaded tendons is highly aligned, whereas the fibers in unloaded tendons are significantly more heterogeneously arranged and crimped. To characterize the collagen fibril response, Small Angle X-ray Scattering is performed. Two types of fibril organizations are found; a single population oriented towards the main load direction and two fibril subpopulations with clearly distinct orientations. Scattering during loading showed that the fibrils in unloaded tendons did not strain as much in fully loaded. In situ loading concurrently with high resolution synchrotron experiments show the complex tendon response to in situ load and its relation to in vivo loading and tendon hierarchical structure. Unloading seems to alter the organization of the fibrils and fibers, e.g. increased crimping and more pronounced sub-tendon twists. Acknowledgements: Funding from Knut and Alice Wallenberg Foundation and European Research Council (101002516). Paul Scherrer Institut, Switzerland for beamtime at cSAXS and TOMCAT

Tendon injuries occur frequently in athletes and the general population, with inferior healing leading to deposition of fibrotic scar tissue. New treatments are essential to limit fibrosis and enable tendon regeneration post-injury. In this study, we tested the hypothesis that rapamycin improves tendon repair and limits fibrosis by inhibiting the mTOR pathway. The left hindlimb of female adult Wistar rats was injured by needle puncture and animals were either given daily injections of rapamycin (2mg/kg) or vehicle. Animals were euthanized 1 week or 3 weeks post-injury (n=6/group). Left and right Achilles tendons were harvested, with the right limbs acting as controls. Tendon sections were stained with haematoxylin & eosin, and scored by 2 blinded scorers, assessing alterations in cellularity, cell morphology, vascularity, extracellular matrix (ECM) organization and peritendinous fibrosis. Immunohistochemistry was performed for the tendon pan-vascular marker CD146 and the autophagy marker LC3. Injury resulted in significantly altered ECM organization, cell morphology and cellularity in both rapamycin and vehicle-treated groups, but no alterations in vascularity compared to uninjured tendons. Rapamycin had a limited effect on tendon repair, with a significant reduction in peritendinous fibrosis 3 weeks after injury (p=0.028) but no change in cell morphology, cellularity or ECM organization compared to vehicle treated tendons at either 1 week or 3 weeks post injury. CD146 labelling was increased at the site of injury, but there was no apparent difference in CD146 or LC3 labelling in rapamycin and vehicle treated tendons. The decrease in peritendinous fibrosis post-injury observed in rapamycin treated tendons indicates rapamycin as a potential therapy for tendon adhesions. However, the lack of improvement of other morphological parameters in response to rapamycin treatment indicates that rapamycin is not an effective therapy for injuries to the tendon core. Acknowledgements: This study was funded by Versus Arthritis (22607)

Tendon injury is debilitating and recalcitrant. With limited knowledge of disease aitiology we have are lacking in effective treatments for this prevalent musculoskeletal complaint. This presentation will outline our findings over the past few years in which we have demonstrated the importance of the interfascicular matrix (IFM) niche in maintaining healthy tendon function and driving disease progression. 1,2. It will also continue to describe our progress in developing both in vivo and in vitro models to interrogate disease progression. We have developed and validated a rat Achilles tendon overload model, in order to explore the impact of loading on IFM and fascicle structure, and the resulting cell response. Data highlights that structural disruption and inflammatory response both initiate in the IFM region, and can be seen in the absence of demonstrable changes to animal gait, indicating a sub-injury response in the tendon which we hypothesis may drive increased matrix turnover and repair. 3. . We are now looking to interrogate the pathways driving this inflammatory behaviour in an organ-chip model, exploring the interplay between IFM cells and cells within fascicles. We have demonstrated phenotypic distinction of cells from the two niche environments, localized the progenitor phenotype to the IFM region and demonstrated significant mechanosensitivity in the IFM cell population. 4. We are currently building appropriate niche environments to maintain cell phenotype in our in vitro models, to explore the metabolic changes associated with disease progression. Acknowledgements: This body of work has received funding from: BBSRC (BB/K008412 /1); Versus Arthritis (project grant 20262); Horserace Betting Levy Board (T5); Dunhill Medical Charity (project grant RPGF1802\23); MRC (MR/T015462/1)

Digital Ventilated Cages (DVC) offer an innovative technology to obtain accurate movement data from a single mouse over time [1]. Thus, they could be used to determine the occurrence of a tendon damage event as well as inform on tissue regeneration [2,3]. Therefore, using the mouse model of tendon experimental damage, in this study it has been tested whether the recovery of tissue microarchitecture and of extracellular matrix (ECM) correlates with the motion data collected through this technology. Mice models were used to induce acute injury in Achilles tendons (ATs), while healthy ones were used as control. During the healing process, the mice were housed in DVC cages (Tecniplast) to monitor animal welfare and to study biomechanics assessing movement activity, an indicator of the recovery of tendon tissue functionality. After 28 days, the AT were harvested and assessed for their histological and immunohistochemical properties to obtain a total histological score (TSH) that was then correlated to the movement data. DVC cages showed the capacity to distinguish activity patterns in groups from the two different conditions. The data collected showed that the mice with access to the mouse wheel had a higher activity as compared to the blocked wheel group, which suggests that the extra movement during tendon healing improved motion ability. The histological results showed a clear difference between different analyzed groups. The bilateral free wheel group showed the best histological recovery, offering the highest TSH score, thus confirming the results of the DVC cages and the correlation between movement activity and structural recovery. Data obtained showed a correlation between TSH and the DVC cages, displaying structural and movement differences between the tested groups. This successful correlation allows the usage of DVC type cages as a non-invasive method to predict tissue regeneration and recovery. Acknowledgements: This research is part of the P4FIT project ESR13, funded by the H2020-ITN-EJD MSCA grant agreement No.955685

The December 2023 Research Roundup³⁶⁰ looks at: Tissue integration and chondroprotective potential of acetabular labral augmentation with autograft tendon: study of a porcine model; The Irish National Orthopaedic Register under cyberattack: what happened, and what were the consequences?; An overview of machine learning in orthopaedic surgery: an educational paper; Beware of the fungus…; New evidence for COVID-19 in patients undergoing joint replacement surgery.

The December 2023 Foot & Ankle Roundup³⁶⁰ looks at: Subchondral bone cysts remodel after correction of varus deformity in ankle arthritis; 3D-printed modular endoprosthesis reconstruction following total calcanectomy; Percutaneous partial bone excision in the management of diabetic toe osteomyelitis; Hemiepiphysiodesis is a viable surgical option for Juvenile hallux valgus; Ankle arthroplasty vs arthrodesis: which comes out on top?; Patient-related risk factors for poorer outcome following total ankle arthroplasty; The Outcomes in Ankle Replacement Study.

The October 2023 Research Roundup. 360. looks at: Gut microbiota in high-risk individuals for rheumatoid arthritis associated with disturbed metabolome and initiates arthritis by triggering mucosal immunity imbalance; International Consensus on Anaemia Management in Surgical Patients (ICCAMS); Sleep disturbance trends in the short-term postoperative period for patients undergoing total joint replacement; Achilles tendon tissue turnover before and immediately after an acute rupture; Quadriceps or hip exercises for patellofemoral pain? A randomized controlled equivalence trial; Total-body MRI for screening in patients with multiple osteochondromas

Aims

This study aimed to establish the optimal fixation methods for calcaneal tuberosity avulsion fractures with different fragment thicknesses in a porcine model.

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.

The August 2023 Foot & Ankle Roundup³⁶⁰ looks at: Achilles tendon rupture: surgery or conservative treatment for the high-demand patient?; First ray amputation in diabetic patients; Survival of ankle arthroplasty in the UK; First metatarsophalangeal joint fusion and flat foot correction; Intra-articular corticosteroid injections with or without hyaluronic acid in the management of subtalar osteoarthritis; Factors associated with nonunion of post-traumatic subtalar arthrodesis; The Mayo Prosthetic Joint Infection Risk Score for total ankle arthroplasty.