Sánchez‐Sotelo, Joaquín

Abstract Normal scapulothoracic function relies on a delicate balance among several periscapular muscles and is essential for shoulder motion. Disturbance in this balance can lead to abnormal motion, which can impair shoulder function, leading to pain and discomfort. A thorough scapular examination requires an accurate physical assessment and the ability to identify pathologies, such as muscle paralysis (e.g., trapezius or serratus anterior) and hyperactivity (e.g., pectoralis minor). Overall, a comprehensive approach to the physical examination is critical in accurately diagnosing and effectively treating shoulder and scapular pathologies. The purpose of this technical note is to provide a concise, standardized methodology for performing a comprehensive scapular examination, focusing on key clinical tests, anatomical landmarks, and motion patterns.

Aims Reliable assessment of joint stiffness is essential for studying arthrofibrosis in preclinical animal models. This study presents a new dedicated biomechanics device for measuring knee stiffness in mouse, rat, and rabbit models of arthrofibrosis, with the aim of validating its performance and comparing it to a previously validated device. Methods The new system integrates a torque load cell, stepper motor, and absolute encoder in a through-hole, unified configuration for precise continuous torque-angle measurement, with custom limb brackets ensuring species-specific alignment at the joint’s centre of rotation. To validate this device and compare it to a previously validated device, arthrofibrosis was induced using established models of extra-articular immobilization in mice and intra-articular violation with immobilization in rats and rabbits, followed by defined remobilization periods. Torque-angle curves were recorded ex vivo across species-specific torque ranges, and measurement variability between the new and a previous validated device was statistically compared using Brown-Forsythe’s test. Results The onset of hyperextension in contralateral limbs occurred at mean angles of 152.4° (mice), 154.4° (rats), and 152.8° (rabbits), and at maximum torque, mean flexion angles were 79.2°, 87.3°, and 140.5°, respectively. No significant differences in measurement variability were observed between devices across all species. Conclusion These findings demonstrate that our new device provides reproducible torque-angle data while maintaining the statistical robustness of the previous device and offering improved mechanical design and operational standardization. By enabling standardized, cross-species joint stiffness quantification, this platform improves cross-study comparability and strengthens the translational reliability of preclinical arthrofibrosis research. Cite this article: Bone Joint Res 2026;15(6):716–725.

Background: The purpose of this study was to describe, and report the outcomes of, a surgical technique that combines reverse shoulder arthroplasty (RSA) using an allograft-prosthetic composite (APC) with a lower trapezius transfer (LTT) to the infraspinatus of the allograft extended with the inferior capsule. Methods: Between 2019 and 2023, 2 surgeons performed a total of 27 RSAs using an APC in conjunction with an LTT. Once the RSA APC reconstruction had been performed, cuff-capsule allograft tissue was passed posterior to the glenosphere and secured to the harvested lower trapezius. One shoulder was resected for periprosthetic joint infection; the remaining 26 shoulders were followed for a minimum of 2 years (mean, 2.7 years; range, 2 to 5 years). Results: The rate of revision or reoperation for humeral complications was 15% and included secondary bone grafting (2 shoulders), resection for infection (1 shoulder), and internal fixation of a periprosthetic fracture (1 shoulder). Other complications requiring surgery included hematoma treated with evacuation (2 shoulders), dislocation (1 shoulder), and glenosphere disassociation (1 shoulder). Preoperatively, 11 shoulders presented with pseudoparalysis, and the mean active elevation of the remaining 16 shoulders was 43°, with only 1 shoulder demonstrating >90° of active elevation. At the most recent follow-up, 3 shoulders were pseudoparalytic, 11 had <90° of active elevation, 8 had >90° of active elevation, and 3 had active elevation to 90°. The overall mean active elevation of the 25 shoulders that could be assessed was 79°. Preoperatively, only 4 (15%) of the 27 shoulders demonstrated active external rotation past neutral; at the most recent follow-up, 80% of surviving shoulders had active external rotation past neutral. Conclusions: LTT at the time of RSA using an APC has the potential to restore active external rotation in shoulders with proximal humeral bone loss and posterosuperior cuff deficiency. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Robotic-assisted reverse shoulder arthroplasty has recently entered early limited clinical use, with the goal of improving the execution of preoperative plans and reducing malposition outliers that increase complication rates and health-care costs. This Innovation article reviews the rationale for this technology, explores its potential impact, examines key implementation challenges, and highlights the future directions needed to determine its ultimate value.

Background: Tendon-bone healing after rotator cuff injury is, or remains, a clinical challenge. Purpose: To examine the role of intraoperative use of purified exosome products (PEPs) in the treatment of rotator cuff injuries and to assess the effect of PEP on supraspinatus tendon-bone healing after rotator cuff repair in a rat model. Study Design: Controlled laboratory study. Methods: This study used 120 Sprague-Dawley rats that underwent an acute supraspinatus tendon transection from the insertion, followed by repair using a single transosseous suture. They were divided into 3 groups: a control group that received only sutures, a TISSEEL group that used a commercially available fibrin sealant patch (TISSEEL) of approximately 0.5 cm 2 , and a PEP-TISSEEL group that used a similarly sized TISSEEL patch combined with PEP. Autopsies were performed at 1, 3, 6, and 8 weeks after surgery. Analyses were performed using molecular biological, biomechanical, and histological techniques. Results: At 6 weeks, the PEP-TISSEEL group achieved greater failure load (mean, 27.5 ± 5.3 N) than the control (mean, 16.4 ± 4.2 N; P = .012) and TISSEEL (mean, 23.4 ± 5.0 N; P = .041) groups, with superiority persisting at 12 weeks (27.2 ± 6.5 N vs 13.1 ± 2.6 N [ P = .002] for the control group and 21.1 ± 5.8 N [ P = .037] for the TISSEEL group). DigiGait showed earlier recovery of stride length and paw angle. Histology revealed organized collagen and reduced scarring, while molecular assays demonstrated early inflammatory modulation with subsequent upregulation of collagen type 1 or 3 and TGF-β, supporting accelerated tendon-bone healing. Conclusion: Intraoperative application of PEP-TISSEEL enhanced tendon-bone healing in a rat model by improving biomechanical strength, promoting enthesis-specific histological regeneration, and accelerating functional recovery as evidenced by gait analysis. Clinical Relevance: The intraoperative application of PEP combined with TISSEEL significantly enhances rotator cuff tendon healing by modulating early inflammation, promoting collagen synthesis, and improving biomechanical properties in a rat model. These findings suggest that PEP-based therapies could offer a promising adjunct in surgical repair, potentially reducing retear rates and improving functional outcomes in patients with rotator cuff injuries. Further clinical studies are warranted to translate these benefits into human applications.

Aims Total elbow arthroplasty (TEA) has shown favourable outcomes in the management of severely comminuted distal humeral fractures in low-demand elderly patients, leading to its increased use in recent years. Less is known about the outcomes of TEA when used for the failure of either internal fixation or conservative management, particularly whether not performing TEA acutely influences the options for further management if fixation fails. This systematic review aimed to assess the clinical and functional outcomes following TEA when used for the post-traumatic sequelae of a distal humeral fracture, and to compare these outcomes with those in patients with a distal humeral fracture who undergo TEA acutely. Methods MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scopus databases were searched from January 2000 to September 2024 for studies reporting complications, reoperations, the range of motion of the elbow, or functional outcomes following the use of TEA in the management of the post-traumatic sequelae of distal humeral fractures, including those due to failed fixation, nonunion, and post-traumatic arthritis. Demographic and clinical data were collected, descriptive statistics were summarized, and meta-analyses were undertaken to compare the outcomes between salvage and acute TEA. Results A total of 16 studies were included, with a total of 380 patients who underwent salvage TEA and 251 who underwent TEA as the initial management. Salvage TEA was associated with a significantly higher overall risk of complications (odds ratio (OR) 2.5 (95% CI 1.0 to 5.9)), though the rate of reoperations did not differ from those who underwent TEA acutely (OR 1.4 (95% CI 0.8 to 2.4)). Pooled analyses revealed a similar postoperative range of flexion (mean difference (MD) -2.4° (95% CI -9.1 to 4.3)) and extension of the elbow (MD 1.1° (95% CI -2.3 to 4.5)) and pronation (MD 0.0° (95% CI -1.1 to 1.1)) and supination (MD -0.0° (95% CI -1.0 to 0.9)) of the forearm. However, salvage TEA showed significantly inferior functional outcomes, as assessed by the Mayo Elbow Performance Score (MD 9.7 (95% CI -18.8 to -0.6)). Conclusion These findings indicate that salvage TEA represents a viable option for the management of post-traumatic sequelae following the teatment of a distal humeral fracture, although patients who underwent salvage TEA had a significantly increased rate of complications and significantly inferior functional outcomes compared with those who underwent TEA acutely. Cite this article: Bone Joint J 2026;108-B(1):21–29.

Aims Arthrofibrosis affects a notable percentage of patients after total knee arthroplasty (TKA). Elevated serum mast cell tryptase (SMCT) levels have been linked to fibrosis, suggesting that SMCT could serve as a biomarker for arthrofibrosis. As such, the aims of this study were to assess SMCT levels in TKA patients, and their possible association with arthrofibrosis and clinical outcomes in a prospective clinical trial. Methods We conducted a prospective study involving 219 patients undergoing primary TKA at a single academic medical centre between January 2018 and December 2022. SMCT levels were measured preoperatively, immediately postoperatively, and at six weeks, three months, and one year postoperatively. Secondary outcomes included revision rates, complications, and Knee Society Scores (KSSs). Allergic and inflammatory conditions were assessed for their influence on SMCT levels. Results At one year postoperatively, eight patients had developed arthrofibrosis (4%), and three (1.5%) had undergone manipulation under anaesthesia. The mean preoperative SMCT level was 5.6 µg/L (SD 3.4), which decreased significantly to 4.1 µg/L (SD 2.7) immediately postoperatively (p < 0.001). At six weeks the mean SMCT level was 6.4 µg/l (SD 4.1), and was 6.1 µg/l at both three months (SD 4.1) and one year (SD 4.0). Elevated preoperative SMCT levels were not significantly associated with the risk of arthrofibrosis development (OR 3; p = 0.370), nor were immediate postoperative levels (OR 2; p = 0.754) or those at six weeks (OR 1; p = 0.989). Of note, elevated SMCT levels at three months (OR 5; 95% CI 0.4 to 64; p = 0.191) and one year (OR 13; 95% CI 1 to 232; p = 0.077) trended toward an increased risk of arthrofibrosis development, without reaching significance. Conclusion In patients undergoing TKA, with the numbers included in this study, there was no significant difference in SMCT levels between patients who did and did not develop arthrofibrosis at any timepoint. However, there was a trend towards elevated SMCT levels at three months and one year in those who developed arthrofibrosis, which merits further study. Cite this article: Bone Joint Res 2025;14(11):1045–1052.

Arthrofibrosis is a common complication following total knee arthroplasty and is the result of a dysregulated immuno-inflammatory cascade, which culminates in excessive scar deposition by myofibroblasts within the knee joint. Pharmacotherapies for arthrofibrosis are limited, with treatment reliant on manipulation under anesthesia or lysis of adhesions with or without component revision. Bupivacaine (a local anesthetic) and meloxicam (a nonsteroidal anti-inflammatory drug) combination therapy may exert antifibrotic properties by limiting inflammatory cell recruitment and the subsequent release of profibrotic cytokines. The purpose of this study was to evaluate the effects of this combination therapy in a rabbit model of arthrofibrosis by evaluating live and postsacrifice knee biomechanics and gene expression of posterior knee capsule tissue. Forty New Zealand white rabbits were equally divided into two experimental groups and prospectively studied to assess knee passive extension angles (PEA), terminal posterior capsular stiffness, and the inflammatory milieu of the posterior knee joint capsule. Experimental limbs with and without combination therapy showed similar live PEAs and terminal posterior capsular stiffness, with no significant differences between the groups. Gene expression analysis, however, revealed significant reduction in inflammatory genes but not profibrotic genes. In summary, bupivacaine and meloxicam combination therapy did not exert antifibrotic effects in a rabbit model of arthrofibrosis but significantly reduced the expression of inflammatory markers in the local environment of the posterior capsule.