MRI findings and clinical testing for preoperative diagnosis of long head of the biceps pathology.

Purpose: Determine whether combining magnetic resonance imaging (MRI) observations and clinical tests could substantially improve sensitivity for diagnosis of long head of the biceps tendon (LHBT) pathology. Methods: The authors retrospectively assessed a consecutive series of 140 patients who underwent arthroscopic rotator cuff repair for isolated supraspinatus tears. The presence of LHBT pathology was assessed preoperatively on MRI using three criteria and four clinical tests specific to shoulder injuries. Binary outcomes of MRI observations and four clinical tests were combined to identify combinations resulting in the best sensitivity using intra-operative arthroscopic findings as reference. Results: The study cohort comprised 100 shoulders (58 men and 42 women) aged 56.6 ± 9.4 years (range, 30-76) at index surgery. A total of 29 combinations were tested to obtain the best diagnostic algorithm for LHBT pathologies. Only four combinations reached a sensitivity ≥0.75, but had a specificity <0.45. The 'Speed or Signal' combination achieved the highest sensitivity (Se: 0.88; 95% confidence interval [CI]: 0.73%-0.96%; Sp: 0.20; 95% CI: 0.10%-0.33%). Conclusion: The most important findings of this study were that, for the diagnosis of LHBT pathology using clinical tests alone, the Speed test had the highest sensitivity (Se, 0.74), and using MRI observations alone, the signal intensity had the highest sensitivity (Se, 0.68). Combination of 'Speed test or Signal intensity' substantially improved the sensitivity (Se, 0.88) but yielded the lowest specificity (Sp, 0.20). The clinical relevance of these findings is that using the combination 'Speed or Signal' for preoperative diagnosis, 88% of pathologic LHBTs would be correctly diagnosed, while 80% of healthy LHBTs could be misdiagnosed as pathologic. Level of Evidence: Diagnostic study, Level IV.

Assessing subscapularis tears: Relationship between special tests and pain & tear severity.

BACKGROUND: The objective of this study is to examine the association between special tests for subscapularis tears and both pain and tear severity. METHODS: Nine hundred and two patients (145 with isolated lesions and 757 with combined lesions) diagnosed with arthroscopically confirmed subscapularis tears between 2010 and 2022. Subscapularis tear severity was classified according to Lafosse classification type I, II, III and IV. Preoperative Visual Analogue Scale (VAS) pain score at rest of the patients, flexion and abduction range of motion (ROM) of the shoulder and the results of the Lift-off test (LOT), Belly Press test (BPT), Bear Hug test (BHT), and Empty Can test (ECT) were documented. RESULTS: The sensitivity of LOT in isolated and combined tears was 70.3 % and 69.5 %, 45.6 % and 41.2 % of BPT, 72.1 % and 72.6 % of BHT, 81.2 % and 84.1 % of ECT, respectively. There was no association between the severity of the subscapularis tear and the sensitivity in all special tests (p > 0.05). Only the ECT was observed to be associated with pain in the multivariate logistic regression analysis (OR = 33.1, p < 0.001). CONCLUSIONS: The special tests used to evaluate subscapularis tears are neither sensitive to the severity of the tear nor to pain except for ECT. BHT is the most successful test to detect any subscapularis tear in both isolated and combined tears. Pain severity was related to the presence of a rotator cuff lesion accompanying subscapularis lesion, but not with the severity of subscapularis or remaining rotator cuff tear. STUDY DESIGN: Levels of Evidence III, cross-sectional archive study. CLINICAL TRIAL REGISTRATION NUMBER: Since the study was a retrospective archive study, there was no clinical trial registration.

Kinect-Based Gait Analysis System Design and Concurrent Validity in Persons with Anterolateral Shoulder Pain Syndrome, Results from a Pilot Study.

As part of an investigation to detect asymmetries in gait patterns in persons with shoulder injuries, the goal of the present study was to design and validate a Kinect-based motion capture system that would enable the extraction of joint kinematics curves during gait and to compare them with the data obtained through a commercial motion capture system. The study included eight male and two female participants, all diagnosed with anterolateral shoulder pain syndrome in their right upper extremity with a minimum 18 months of disorder evolution. The participants had an average age of 31.8 ± 9.8 years, a height of 173 ± 18 cm, and a weight of 81 ± 15 kg. The gait kinematics were sampled simultaneously with the new system and the Clinical 3DMA system. Shoulder, elbow, hip, and knee kinematics were compared between systems for the pathological and non-pathological sides using repeated measures ANOVA and 1D statistical parametric mapping. For most variables, no significant difference was found between systems. Evidence of a significant difference between the newly developed system and the commercial system was found for knee flexion-extension (p < 0.004, between 60 and 80% of the gait cycle), and for shoulder abduction-adduction. The good concurrent validity of the new Kinect-based motion analysis system found in this study opens promising perspectives for clinical motion tracking using an affordable and simple system.

Arthroscopic procedures for degenerative rotator cuff disease: a systematic review and network meta-analysis.

BACKGROUND: Treatment of rotator cuff diseases often involves various arthroscopic procedures but their combined effectiveness remains contentious, especially in complex cases. METHODS: We focused on patients with degenerative shoulder cuff diseases requiring arthroscopic rotator cuff repair. Searches covered multiple databases (Medline, Embase, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Cochrane Clinical Answers) up to April 1, 2024. Bias risk was assessed using RevMan (v 5.4), and a network meta-analysis was conducted with netmeta (v 2.8). RESULT: From 16 studies, 1232 patients (average age, 56.2 years; balanced sex ratio) were included. Arthroscopic rotator cuff repair ranked highest in functional score networks, surpassing other interventions. Physiotherapy was superior for pain relief compared to arthroscopic procedures combined with platelet-rich plasma (mean, 2.5; 95% confidence interval, 4.48-0.52). Arthroscopic rotator cuff repair and subacromial decompression were significantly superior to arthroscopic rotator cuff repair and subacromial decompression combined with platelet-rich plasma (MD, 1.80; 95% CI, 3.39-0.21). DISCUSSION: Moderate bias risks were noted in both networks due to blinding issues and methodological quality reporting. Arthroscopic rotator cuff repair is favored for improving shoulder function, while other procedures or intra-articular treatments offer no significant benefits. Regarding pain management, physiotherapy is preferred; however, more evidence is needed to support this recommendation and caution is advised. OTHER: Systematic review registration PROSPERO CRD42023450150.

Suramin enhances proliferation, migration, and tendon gene expression of human supraspinatus tenocytes.

Rotator cuff tendinopathy is a common musculoskeletal disorder with limited pharmacological treatment strategies. This study aimed to investigate tenocytes' functional in vitro response from a ruptured supraspinatus tendon to suramin administration and to elucidate whether suramin can enhance tendon repair and modulate the inflammatory response to injury. Tenocytes were obtained from human supraspinatus tendons (n = 6). We investigated the effect of suramin on LPS-induced inflammatory responses and the underlying molecular mechanisms in THP-1 macrophages. Suramin enhanced the proliferation, cell viability, and migration of tenocytes. It also increased the protein expression of PCNA and Ki-67. Suramin-treated tenocytes exhibited increased expression of COL1A1, COL3A1, TNC, SCX, and VEGF. Suramin significantly reduced LPS-induced iNOS, COX2 synthesis, inflammatory cytokine TNF-α production, and inflammatory signaling by influencing the NF-κB pathways in THP-1 cells. Our results suggest that suramin holds great promise as a therapeutic option for treating rotator cuff tendinopathy.

A match-pair analysis of single row vs transosseous equivalent double row in massive posterosuperior rotator cuff tears in patients > 70 years old.

INTRODUCTION: The aim of this study was to compare the results of single versus double row (TEO) in massive tears of the posterosuperior rotator cuff in patients older than 70 years old. METHODS: Between October 2019 and July 2022, 46 patients, older than 70 years old, were operated on, in two centers, by one surgeon (FM), in one center, we performed a single-row repair, while in the other a double row, transosseous equivalent. Patients were paired by age and gender. All patients were studied with a preoperative MRI along with preoperative age and gender adjusted constant score. Postoperative patients were evaluated at the end of the FU. Mean time of FU for single row was 3.2 years (2-4.1) and for TOE was 3.5 years (2.4-3). Mean age for SR patients was 71.15 years (70-82) and for TOE was 74.8 years (70-81). We were able to evaluate 20 pairs of patients (15 pairs of females and five pairs of males). RESULTS: CS differed in both groups of patients. Patients operated on with TOE had a better, but non-significant CS 81.3 (TOE) versus 75.7 (SR) p > 0.05. The patients operated own with TOE showed statistically significant better arm abduction strength than patients operated on with SR (p < 0.05). There was a trend for patients operated on with TOE to have a better ROM and less pain. DISCUSSION: The results of our work show that patients older than 70 years old, with repairable RCT operated on with a transosseous equivalent, have a trend to have a better CS and a significantly better strength than patients operated on with SR.

Biologically Enhanced Patch in the Healing and Mechanical Stability of Rotator Cuff Tears.

Biological patches have emerged as promising adjuncts in the surgical management of rotator cuff tears, aiming to enhance tissue healing and biomechanical properties of repaired tendons. These patches, derived from human or animal sources such as dermis or small intestinal submucosa, undergo mechanical and pathological changes within the rotator cuff environment post-implantation. These patches provide structural reinforcement to the repair site, distributing forces more evenly across the tendon and promoting a gradual load transfer during the healing process. This redistribution of forces helps alleviate tension on the repaired tendon and surrounding tissues, potentially reducing the risk of re-tears and improving overall repair integrity. Moreover, biological patches serve as scaffolds for cellular infiltration and tissue ingrowth, facilitating the recruitment of cells and promoting collagen synthesis. The integration of these patches into the host tissue involves a cascade of cellular events, including inflammation, angiogenesis, and matrix remodeling. Inflammatory responses triggered by patch implantation contribute to the recruitment of immune cells and the release of cytokines and growth factors, fostering a microenvironment conducive to tissue repair. However, despite their potential benefits, the long-term efficacy and durability of biological patches in rotator cuff repair remain areas of ongoing research and debate. Further studies are needed to elucidate the optimal patch characteristics, surgical techniques, and rehabilitation protocols to maximize clinical outcomes and minimize complications in rotator cuff surgery.

A Cadaveric Study of the Rotator Cable: Interrogating the Suspension Bridge Model.

Purpose The objective of this cadaveric study was to describe the anatomical relationships between the rotator cuff muscles and the rotator cable. Methods In 30 formaldehyde-fixed shoulders from 20 cadavers, the rotator cuff and rotator cable were dissected and the glenohumeral joint opened. The orientation and attachments of the rotator cable to the rotator cuff muscles were described, and the severity of any osteoarthritis, labral pathology, and rotator cuff pathology present was documented. The width and thickness of the infraspinatus attachments to the rotator cable were measured. Results The infraspinatus muscle was noted to be more loosely adherent to the rotator cable, while the supraspinatus and teres minor were tightly adherent to the cable. Specifically, the superior-most portion of the infraspinatus was found to be less tightly adherent than the inferior-most portion in 26 of the 30 shoulders studied. The thickness/width ratio of the inferior-most portion of infraspinatus was significantly different in shoulders with more-than-minimal osteoarthritis and labral pathology (p=0.048 and p=0.041, respectively). Conclusion While the supraspinatus and teres minor muscles were tightly adherent to the cable in all shoulders, the degree of attachment of the superior-most portion of the infraspinatus muscle was notably less in 26 of the 30 shoulders studied. This could mean that only the inferior portion of the infraspinatus participates in stress shielding through the cable or be a compensatory response to increased load on the tendon. This work is expected to provide insight into the function of the rotator cable and the different functions of the infraspinatus.

Engineered Tendon-Fibrocartilage-Bone Composite With Mechanical Stimulation for Augmentation of Rotator Cuff Repair: A Study Using an In Vivo Canine Model With a 6-Month Follow-up.

BACKGROUND: Rotator cuff repair augmentation using biological materials has become popular in clinical practice to reduce the high retear rates associated with traditional repair techniques. Tissue engineering approaches, such as engineered tendon-fibrocartilage-bone composite (TFBC), have shown promise in enhancing the biological healing of rotator cuff tears in animals. However, previous studies have provided limited long-term data on TFBC repair outcomes. The effect of mechanical stimulation on TFBC has not been explored extensively. PURPOSE: To evaluate functional outcomes after rotator cuff repair with engineered TFBC subjected to mechanical stimulation in a 6-month follow-up using a canine in vivo model. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 40 canines with an acute infraspinatus (ISP) tendon transection model were randomly allocated to 4 groups (n =10): (1) unilateral ISP tendon undergoing suture repair only (control surgery); (2) augmentation with engineered TFBC alone (TFBC); (3) augmentation with engineered TFBC and bone marrow-derived stem cells (BMSCs) (TFBC+C); and (4) augmentation with engineered TFBC and BMSCs, as well as mechanical stimulation (TFBC+C+M). Outcome measures-including biomechanical evaluations such as failure strength, stiffness, failure mode, gross appearance, ISP tendon and muscle morphological assessment, and histological analysis-were performed 6 months after surgery. RESULTS: As shown in the mechanical test, the TFBC+C+M group exhibited higher failure strength compared with other repair techniques. The most common failure mode was avulsion fracture in the TFBC+C+M group, but tendon-bone junction rupture was observed predominantly in different groups. Engineered TFBC with mechanical stimulation showed over 70% relative failure strength compared with normal ISP, and the other groups showed about 50% relative failure strength. Histological analysis revealed less fat infiltration and closer-to-normal muscle fiber structure in the mechanical stimulation group. CONCLUSION: This study provides evidence that mechanical stimulation of engineered TFBC promotes rotator cuff regeneration, thus supporting its potential for rotator cuff repair augmentation. CLINICAL RELEVANCE: This study provides valuable evidence supporting the use of a novel tissue-engineered material (TFBC) in rotator cuff repair and paves the way for advancements in the field of rotator cuff regeneration.

Comparative Analysis of Bone Mineral Density of the Lumbar Spine, Hip, and Proximal Humerus in Patients with Unilateral Rotator Cuff Tears.

Background: The proximal humerus, a common site for osteoporotic fractures, is frequently overlooked in osteoporosis evaluations. This study aimed to evaluate the relationship between the conventional bone mineral density (BMD) measurement (at the lumbar spine and femur) and the BMD measurement at both proximal humeri (the asymptomatic side and the side with a rotator cuff tear [RCT]) in patients with unilateral RCT. Furthermore, we investigated clinical features indicative of osteoporosis in RCT patients and assessed the utility of proximal humerus BMD measurements. Methods: From April 2020 to September 2020, 87 patients who underwent arthroscopic repairs for unilateral RCTs were examined for age, onset, body mass index, menopause duration, passive range of motion, global fatty degeneration index, and RCT and retraction size. The regions of interest (ROIs) for the conventional BMD included the lumbar spine, femur neck, femur trochanter, and total femur. For the proximal humerus BMD, the ROIs included the head, lesser tuberosity, greater tuberosity (medial, middle, and lateral rows), and total humerus. Results: The conventional BMD of the lumbar spine, femur neck, femur trochanter, and femur total were 1.090, 0.856, 0.781, and 0.945 g/cm2, respectively. The head, lesser tuberosity, greater tuberosity (medial, middle, and lateral rows), and total BMD of the asymptomatic-side proximal humerus were 0.547, 0.544, 0.697, 0.642, 0.554, and 0.610 g/cm2, respectively. The average of proximal humerus BMD was significantly lower than that of conventional BMD (p < 0.001). All ROIs BMD of the RCT-side proximal humerus were 0.497, 0.507, 0.619, 0.598, 0.517, and 0.560 g/cm2. There was no correlation between the conventional BMD and each proximal humerus BMD. All ROI BMD of the RCT-side proximal humerus was not significant in the multiple regression analysis with age, onset, body mass index, passive range of motion, global fatty degeneration index, and RCT and retraction size (p > 0.05). Conclusions: The proximal humerus BMD showed a completely different trend from that of conventional BMD and had no significant association with clinical features. Therefore, the proximal humerus BMD needs to be measured separately from the conventional BMD, as it may provide important information before rotator cuff repair surgery.

Isolated Latissimus Dorsi Transfer versus Combined Latissimus Dorsi and Teres Major Tendon Transfer for Irreparable Anterosuperior Rotator Cuff Tears.

Background: Irreparable anterosuperior rotator cuff tears (IASRCTs) present significant challenges, especially in young, active patients with limited joint-preserving options. Recently, latissimus dorsi (LD) transfer and combined latissimus dorsi and teres major (LDTM) transfer have gained attention as a potential surgical option. We aimed to compare the clinical and radiological outcomes of LD versus combined LDTM transfer in IASRCTs. Methods: In this retrospective comparative study, 53 patients with IASRCTs were analyzed after undergoing either LD transfer attached to lesser tuberosity (LT) (LD group, n = 23) or combined LDTM transfer attached to greater tuberosity (GT) (LDTM group, n = 30). Clinical evaluations included the visual analog scale score for pain, active shoulder range of motion (ROM), University of California Los Angeles Shoulder Score, American Shoulder and Elbow Surgeons score, activities of daily living that require active internal rotation (ADLIR) scores, and subscapularis (SSC)-specific examinations. Radiographic analyses involved assessing acromiohumeral distance (AHD), Hamada grade, the rate of anterior glenohumeral subluxation reduction, and integrity of the transferred tendon. Results: Postoperatively, both groups demonstrated significant improvements in pain and clinical scores (p < 0.001). At the 2-year follow-up, the LDTM group showed superior internal rotation strength (p < 0.001), ADLIR score (p = 0.017), and SSC-specific physical examination results (belly-press, p = 0.027; bear-hug, p = 0.031; lift-off, p = 0.032). No significant changes in AHD or Hamada grade were observed in either group. At final follow-up, no significant differences were found between the 2 groups in terms of AHD (p = 0.539) and Hamada grade (p = 0.974). Although preoperative anterior glenohumeral subluxation was improved in both groups, the LDTM group showed a statistically significantly higher rate of restoration compared to the LD group (p = 0.015). Conclusions: While both LD and combined LDTM transfers for IASRCTs improved postoperative pain relief, clinical scores, and active ROM, the combined LDTM transfer attached to GT was superior to LD transfer attached to LT in terms of internal rotational strength, ADLIR score, and SSC-specific examinations. Neither group showed significant progress in cuff tear arthropathy or decreased AHD at 2-year follow-up; however, the combined LDTM transfer notably improved preoperative anterior glenohumeral subluxation.

Establishing a rabbit model with massive supraspinatus tendon defect for investigating scaffold-assisted tendon repair.

BACKGROUND: Shoulder pain and disability from rotator cuff tears remain challenging clinical problem despite advancements in surgical techniques and materials. To advance our understanding of injury progression and develop effective therapeutics using tissue engineering and regenerative medicine approaches, it is crucial to develop and utilize animal models that closely resemble the anatomy and display the pathophysiology of the human rotator cuff. Among various animal models, the rabbit shoulder defect model is particularly favored due to its similarity to human rotator cuff pathology. However, a standardized protocol for creating a massive rotator cuff defect in the rabbits is not well defined. Therefore, the objective of our study was to establish a robust and reproducible model of a rotator cuff defect to evaluate the regenerative efficacy of scaffolds. RESULTS: In our study, we successfully developed a rabbit model with a massive supraspinatus tendon defect that closely resembles the common rotator cuff injuries observed in humans. This defect involved a complete transection of the tendon, spanning 10 mm in length and encompassing its full thickness and width. To ensure stable scaffolding, we employed an innovative bridging suture technique that utilized a modified Mason-Allen suture as a structural support. Moreover, to assess the therapeutic effectiveness of the model, we utilized different scaffolds, including a bovine tendon extracellular matrix (ECM) scaffold and a commercial acellular dermal matrix (ADM) scaffold. Throughout the observation period, no scaffold damage was observed. Notably, comprehensive histological analysis demonstrated that the regenerative tissue in the tendon ECM scaffold group exhibited an organized and aligned fiber structure, indicating tendon-like tissue regeneration while the tissue in the ADM group showed comparatively less organization. CONCLUSIONS: This study presents a comprehensive description of the implemented procedures for the development of a highly reproducible animal model that induces massive segmental defects in rotator cuff tendons. This protocol can be universally implemented with alternative scaffolds to investigate extensive tendon defects and evaluate the efficacy of regenerative treatments. The application of our animal model offers a standardized and reproducible platform, enabling researchers to systematically evaluate, compare, and optimize scaffold designs. This approach holds significant importance in advancing the development of tissue engineering strategies for effectively repairing extensive tendon defects.

Comparison between four different suture configurations for rotator cuff repair: a biomechanical animal study.

INTRODUCTION: The arthroscopic repair of a massive rotator cuff tear could be surgically challenging. There is a continuous argument regarding the best surgical technique and suture configuration used to treat massive rotator cuff tears. The purpose of this study was to assess the in vitro strength of the new double Mason-Allen suture and compare it to the commonly used other suture configurations. METHODS: Twenty-five fresh sheep shoulders were randomly divided into five equal groups. Each group had their infraspinatus tendons cut and repaired with one of five suture configurations (simple, horizontal mattress, Mason-Allen, modified Mason-Allen, and double Mason-Allen) using Arthrex® 1.3 mm suture tape. The specimens were fixed to the test apparatus through their scapulae and hung with the repair tape to Sartorius® precision balance with sequential load increments till failure. The load to failure was measured for each of the five suture configurations. RESULTS: Study data found the double Mason-Allen configuration to have the highest mean load to failure 423.30 ± 23.05 (Newtons), followed by modified Mason-Allen, Mason-Allen, horizontal mattress, and simple suture respectively. CONCLUSION: The double Mason-Allen repair configuration has the highest load to failure compared to the other known suture configuration to repair rotator cuff tears.

Structural and Functional Alterations of the Deltoid Muscle After Arthroscopic Rotator Cuff Repair: A 2-Year Longitudinal Observation Study.

Background: Deltoid muscle detachment and atrophy have been reported to occur after shoulder surgery. Purpose: To investigate the 2-year changes in deltoid muscle structure and function after arthroscopic rotator cuff repair (ARCR) using magnetic resonance imaging (MRI) and electrophysical examination. Study Design: Case series; Level of evidence, 4. Methods: A total of 72 patients (72 shoulders) who underwent ARCR between 2015 and 2020 were enrolled. Whole deltoid muscle volume and regional (anterior, lateral, and posterior) muscle thicknesses were determined on T2-weighted MRI scans of both shoulders taken preoperatively and at 1, 3, 6, 12, and 24 months postoperatively, and their correlations with compound muscle action potentials (CMAPs), shoulder abduction muscle strength, and Constant scores were investigated. Comparison between groups was performed using paired or Student t tests, and the relationship between deltoid muscle volume and various factors was determined using Pearson correlation analysis. Results: The volume of the deltoid muscle on the affected side decreased from 44,369 ± 12,371 mm3 preoperatively to 38,139 ± 10,615 mm3 at 1 month postoperatively (P < .05), representing a 14% decrease. The deltoid muscle volume of the contralateral side also significantly decreased during the same time frame, from 43,278 ± 12,248 to 40,273 ± 11,464 mm3 (P < .05), representing a 7% decrease at 1 month postoperatively. Subsequently, the deltoid muscle volume on both sides recovered to preoperative levels at 12 months and was maintained at 24 months. Only the thickness of the anterior part of the deltoid was markedly decreased, from 13.9 ± 3.7 mm preoperatively to 12.0 ± 3.2 mm at 1 month postoperatively (P < .05), representing a 14% reduction. The CMAP amplitude showed a significant decrease at 1 month postoperatively; however, no significant difference was observed after 12 months when compared with the preoperative values or the values on the contralateral side. Positive correlations were found between deltoid muscle volume and CMAP amplitude at 24 months as well as between deltoid muscle volume and shoulder abduction muscle strength (R 2 = 0.698; P < .05) and Constant score (R 2 = 0.133; P < .05). Conclusion: Our study demonstrated that the early structural and functional decline of the deltoid muscle after ARCR was fully recovered within 1 year, confirming that this procedure does not negatively affect the deltoid muscle.

Ultrasound-Guided Glucocorticoid Injection as a Treatment for Rotator Cuff Calcific Tendinopathy: A Case Report.

Rotator cuff calcific tendinopathy (RCCT) is a common disorder of the rotator cuff causing shoulder pain and dysfunction. RCCT is characterized by calcium deposition on and around the tendons of the rotator cuff muscles. Treatment is typically conservative, consisting of anti-inflammatory drugs (NSAIDs) and physical therapy, although certain patients require more invasive treatment. If first-line treatments do not resolve the pain, second-line treatments such as glucocorticoid injections, extracorporeal shock wave therapy (ESWT), barbotage, and surgery may be considered; however, there is no gold standard treatment for these refractory cases. In this case study, a 36-year-old female patient with confirmed RCCT achieved symptom remission with ultrasound-guided methylprednisolone injection followed by adjunctive physical therapy. Ultrasonography enabled precise, targeted delivery of steroids to the calcified lesions, with near 100% resolution of deposits on repeat radiography. With additional physical therapy, the patient was completely pain-free with a full range of motion and the ability to perform daily activities. This case report demonstrates that ultrasound-guided glucocorticoid injection can be an efficacious treatment option for refractory cases of RCCT.

Infection following mini-open rotator cuff repair: a single surgeon experience.

BACKGROUND: Surgical technique has been shown to influence risk of surgical site infection following rotator cuff repair (RCR). Few studies have reported the rate of infection associated with mini-open RCR. The goal of this study was to report the postoperative infection rate and risk factors for infection among patients undergoing RCR performed by a single surgeon using a modified mini-open technique. Our hypothesis was that the rate of infection after mini-open RCR would be lower than previously reported for this surgical approach. METHODS: We retrospectively reviewed an institutional shoulder surgery database to identify patients who underwent mini-open RCR performed by one surgeon at an academic tertiary care institution between 2003 and 2020. Patient records were reviewed to determine which individuals returned within 3 months postoperatively with a superficial or deep surgical site infection requiring operative management. Patient demographics, preoperative clinical characteristics, intraoperative variables, microbiological findings, infection management, and clinical course after infection were recorded. Backward elimination multivariate regression was used to assess for significant risk factors for infection. RESULTS: Of the 925 patients identified, 823 (89%) had at least 3 months of follow-up and were included for further analysis. A majority of the patients undergoing RCR were men (57%). The mean age was 58.4 ± 9.9 years, and the mean body mass index was 29.3 ± 5.9 kg/m2. Fourteen cases (1.7%) of postoperative surgical site infection were identified in 13 patients. Ten infections (1.2%) were superficial and 4 (0.49%) were deep. The most commonly identified organisms were Staphylococcus aureus and Cutibacterium acnes. Male sex (odds ratio [OR] 4.3, 95% CI 1.2-15.3) and diabetes mellitus (OR 3.9, 95% CI 1.2-12.6) were found to be associated with greater risk of infection. The RCR construct was found to be intact in all 10 patients with superficial infections and 2 of the 4 patients with deep infections. All infections were successfully treated with 1 round of surgical débridement and wound irrigation, and with 6 or fewer weeks of intravenous antibiotic therapy. All patients with postoperative infections recovered with no sequelae at a median final follow-up of 63.5 months (range, 3-215 months). CONCLUSIONS: This single-surgeon series of a large patient cohort undergoing mini-open RCR over an 18-year period demonstrated a low overall infection rate of 1.7%. Only 4 infections were deep, which suggests that deep infection after mini-open RCR is uncommon and approximates infection rates seen with arthroscopic techniques.

Soluble allogenic telocollagen as a direct protein therapeutic: Results of serial injections in a rodent rotator cuff tear model.

HYPOTHESIS: Delivery of soluble allogeneic type I telocollagen (allo-telocollagen) will accelerate and improve the healing of damaged tendons. Our hypothesis draws from known mechanochemical properties of type I collagen that direct its incorporation into damaged connective tissue. We further suggest that allo-telocollagen will raise a minimal immunogenic reaction due to homology within species. METHODS: Seventy-eight shoulders (39 Sprague-Dawley rats) had their supraspinatus tendon surgically detached from its footprint on the humerus and repaired (72 shoulders) or left uninjured (6 shoulders). The repaired tissue was treated with an injection of 100 µl of saline, 10 mg/ml allogeneic atelocollagen (allo-atelocollagen), or 10 mg/ml allo-telocollagen at 0-, 1-, and 2-weeks post-surgery. At 30- and 60-days post-surgery, the tendons were assessed by mechanical testing (failure load, failure stress, stiffness, and relaxation) and by semiquantitative histological scoring. RESULTS: At 30-days post-surgery, the mechanical and histological outcomes were not statistically different. However, at day 60, allo-telocollagen improved the failure strength of the supraspinatus (29.9 ± 4.7 N) relative to saline (20.0 ± 3.5 N; P value <= 0.001) or allo-atelocollagen (23.2 ± 1.5 N; P value = 0.025) treated tendons, and it approached that of uninjured controls (36.9 ± 5.0 N; P value = 0.021). Allo-telocollagen improved the failure stress of the supraspinatus (34.1 ± 9.3 MPa) relative to the saline treated tendons (21.4 ± 6.0 MPa; P value = 0.031; 160% improvement) and was no different than uninjured controls (33.4 ± 9.9 MPa; P value = 0.999) or allo-atelocollagen (32.3 ± 7.4 MPa; P value = 0.977). The stiffness of uninjured controls was far greater than any of injured/treated tendons (>200% stiffer). Histological scoring showed that the allo-telocollagen treated tendons produced better collagen fiber arrangement (1.55 ± 0.17) than saline (2.50 ± 0.29; P value = 0.001) or allo-atelocollagen (2.23 ± 0.28; P value = 0.042) treated tendons and that it did not increase markers of immunogenesis (1.10 ± 0.42) relative to either saline (1.44 ± 0.20; P value = 0.369) or allo-atelocollagen (0.68 ± 0.41; P value = 0.1058). CONCLUSIONS: While all three treatments produced similar results at 30 days, by 60 days, soluble allo-telocollagen clearly separated from the other interventions, yielding better mechanical and histological outcomes in a torn/repaired rotator cuff rat model. Allo-telocollagen treated tendons also approached the failure strength and matched the failure stresses of uninjured control tendons. The data suggest a new use for allo-telocollagen as a deliverable direct protein mechanotherapeutic that can improve both healing quality and speed.

A reduced scapulo-humeral angle contributes to the development of scapular notching in reverse total shoulder arthroplasty.

PURPOSE: Scapular Notching (SN) is one of the most common postoperative complications for a patient after Reverse Total Shoulder Arthroplasty (RTSA). Despite employing various strategies to mitigate SN risk, the overall incidence remains far from zero. This article introduces a new risk factor, the scapulo-humeral angle (SHA), as a key element influencing the risk for SN. METHODS: A retrospective analysis was conducted on all patients who underwent RTSA for rotator cuff arthropathy at the study centre. The preoperative SHA was measured, and the presence of SN was investigated and graded using the Nerot classification at the latest follow-up. RESULTS: 42 patients were included. 12 presented SN (incidence 28.5%). A statistically significant Pearson coefficient correlation between pre-operative SHA and the incidence of SN was observed (r= -0.6954; 95% C.I. -0,8250 to -0,4963; p < 0.0001). A statistically significant Pearson coefficient correlation was also found between the degree of SN and the pre-operative SHA (r= -0,7045; 95% C.I. -0,8306 to -0,5096; P value (two-tailed) < 0,0001, alpha 0.05). CONCLUSIONS: The primary finding is a statistically significant correlation between a reduced preoperative SHA and an increased incidence of postoperative SN. The secondary finding is that a smaller preoperative SHA is associated with a more severe degree of SN A SHA cut-off of 50° distinguished patients at high risk of SN from those at low risk. All patients with an SHA below 50° developed SN (10/10), whereas only 6.25% of patients with an SHA exceeding 50° experienced SN (2/32).