The Self-Assessment Corner for Shoulder Strength: Reliability, Validity, and Correlations With Upper Extremity Physical Performance Tests.

CONTEXT: Rotator cuff weakness and rotation ratio imbalances are possible risk factors for shoulder injury among overhead athletes. In consensus statements, organizations have highlighted the importance of a screening examination to identify athletes at risk of injury. The screening should be portable and designed to be feasible in many different environments and contexts. OBJECTIVE: To evaluate the reliability and validity of the Self-Assessment Corner (SAC) for self-assessing shoulder isometric rotational strength and examining whether performance on 2 physical performance tests was correlated with isometric shoulder rotational strength using the SAC in handball players. DESIGN: Cross-sectional study. SETTING: Sport setting. PATIENTS OR OTHER PARTICIPANTS: A first sample of 42 participants (18 men, 24 women) was recruited to determine the reliability and validity of the SAC. In a second sample of 34 handball players (18 men, 16 women), we examined correlations between physical performance tests and the SAC. MAIN OUTCOME MEASURE(S): The SAC was used to measure isometric rotational strength with the upper extremity at 90° of abduction in the frontal plane and 90° of external rotation and the elbow flexed to 90° with neutral rotation of the forearm. The SAC findings were compared with those from manual testing. Results from the seated medicine ball throw (SMBT) and closed kinetic chain upper extremity stability test (CKCUEST) were used to establish relationships with the SAC. We calculated intraclass correlation coefficients to determine relative reliability and used standard error of measurement and minimal detectable change to quantify absolute reliability. Relationships among the different strength-testing procedures and with the physical performance tests were determined using the Pearson product moment correlation coefficient (r) or Spearman rank correlation coefficient (rs). RESULTS: We observed good to excellent reliability (intraclass correlation coefficient [2,k] range = 0.89 to 0.92). The standard error of measurement varied from 3.45 to 3.48 N. The minimal detectable change with 95% confidence intervals ranged from 8.06 to 8.13 N. Strong correlations were present among strength procedures (r = 0.824, rs range = 0.754-0.816). We observed moderate to strong correlations between the CKCUEST findings and rotational strength (r range = 0.570-0.767). Moderate correlations were found between rotational strength and SMBT (r range = 0.573-0.626). CONCLUSIONS: The SAC is a clinically applicable and standardized protocol for self-assessing rotational strength in young healthy adults without pathologic conditions. Performance on the SMBT and CKCUEST may be valuable as a screening tool to further assess shoulder strength.

Lose-Dose Administration of Dexamethasone Is Beneficial in Preventing Secondary Tendon Damage in a Stress-Deprived Joint Injury Explant Model.

Secondary joint damage is the process by which a single injury can lead to detrimental changes in adjacent tissue structures, typically through the spread of inflammatory responses. We recently developed an in vitro model of secondary joint damage using a murine rotator cuff explant system, in which injuries to muscle and bone cause massive cell death in otherwise uninjured tendon. The purpose of the present study was to test the ability cytokine-targeted and broad-spectrum therapeutics to prevent cell death and tissue degeneration associated with secondary joint damage. We treated injured bone-tendon-muscle explants with either interleukin-1 receptor antagonist, etanercept, or dexamethasone (DEX) for up to 7 days in culture. Only the low-dose DEX treatment was able to prevent cell death and tissue degeneration. We then identified a critical window between 24 and 72 h following injury for maximal benefit of DEX treatment through timed administration experiments. Finally, we performed two tendon-only explant studies to identify mechanistic effects on tendon health. Interestingly, DEX did not prevent cell death and degeneration in a model of cytokine-induced damage, suggesting other targets of DEX activity. Future studies will aim to identify factors in joint inflammation that may be targeted by DEX treatment, as well as to investigate novel delivery strategies. Statement of clinical significance: Overall, this work demonstrates beneficial effects of DEX administration on preventing tenocyte death and extracellular matrix degeneration in an explant model of secondary joint damage, supporting the clinical use of low-dose glucocorticoids for short-term treatment of joint inflammation. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:139-149, 2020.

Subscapularis-Sparing Total Shoulder Arthroplasty: A Prospective, Double-Blinded, Randomized Clinical Trial.

Although total shoulder arthroplasty (TSA) is generally associated with good to excellent outcomes in most patients, the integrity and function of the subscapularis tendon (SSC) is of paramount importance because SSC rupture after TSA can lead to inferior outcomes. Therefore, the efficacy of a SSC-sparing TSA procedure was evaluated through a prospective, double-blinded, randomized study. Patients with end-stage osteoarthritis of the shoulder were randomized into 2 groups. Group 1 patients were treated with TSA in which the prosthesis was inserted entirely through the rotator interval without violating the SSC tendon (SPARING). Group 2 patients were treated with TSA using the SSC tenotomy approach (STANDARD). Both the patients and the evaluators remained blinded to the surgical approach throughout the study. Outcome data collected included the visual analog scale score for pain and the American Shoulder and Elbow Surgeons outcome score. Complete 2-year outcome data were collected from 32 SPARING and 38 STANDARD patients at a mean follow-up of 31.1 and 33.4 months, respectively. The American Shoulder and Elbow Surgeons and visual analog scale scores improved significantly for both groups. Differences between groups did not reach statistical significance. Complication profiles were similar for the 2 groups, with 3 patients in the SPARING group and 2 patients in the STANDARD group requiring revision surgery during the study. At short-term follow-up, the outcome of TSA using the SSC-sparing surgical approach was similar to the outcome of TSA using the standard approach. Studies with longer follow-up are required to document the potential benefits of this surgical technique. [Orthopedics. 2019; 42(1):e61-e67.].

Influence of the site of acromioplasty on reduction of the critical shoulder angle (CSA) - an anatomical study.

BACKGROUND: A large critical shoulder angle (CSA) >35° is associated with the development of rotator cuff tearing. Lateral acromioplasty (AP) has the theoretical potential to prevent rotator cuff tearing and/ or to reduce the risk of re-tears after repair. It is, however unclear which part of the lateral acromion has to be reduced to obtain the desired CSA. It was the purpose of this study to determine which part of the lateral acromion has to be resected to achieve a desired reduction of the CSA in a given individual. METHODS: First, the influence of the exact radiographic projection on the CSA was examined. Second, the influence of anterolateral versus strict lateral AP on the CSA was studied in eight scapulae with different anatomic characteristics. Differences in CSA reduction were investigated using paired t-test or Wilcoxon test. RESULTS: Scapular rotation in the sagittal and axial plane had a marked influence on the radiologically measured CSA ranging from -6 to +16°. Overall, lateral AP of 5/10mm reduced the CSA significantly greater than anterolateral AP of 5mm/10mm [5mm: 2.3° (range: 0.7°-3.6°) SD±0.8° vs. 1.2° (range: 0°-3.3°) SD±1.1°, p=0.0002]/[10mm: 4.8° (range: 2.1°-7°) SD±1.3° vs. 2.7° (range: 0°-5.3°) SD±1.7°, p=0.0001]. Depending on scapular anatomy anterolateral AP did not alter CSA at all. CONCLUSIONS: For comparison of pre- and postoperative CSA, the exact orientation of the X-ray and the spatial orientation of the scapula must be as identical as possible. Anterolateral AP may not sufficiently correct CSA in scapulae with great acromial slopes and smaller relative external rotation of the acromion as the critical acromial point (CAP) may be located too posteriorly and thus is not addressed by anterolateral acromioplasty. Consistent reduction of the CSA could be achieved by lateral AP in all eight scapulae.

Apoptosis and rotator cuff tears: scientific evidence from basic science to clinical findings.

Introduction: Excessive apoptosis has been hypothesized as possible cause of tendinopathy and tear in the tendons of the rotator cuff (RC). Different mechanisms and molecules play a key role in cell regulation. Biological interventions can affect the process of apoptosis to control the tendinopathy process, and may be useful to design new treatments. Source of data: We identified basic science, in vitro and in vivo preclinical and clinical studies listed in the Pubmed Google Scholar, CINAHL, Cochrane Central and Embase Biomedical databases in English, Spanish, Italian and French concerning the effects of apoptosis on RC tendons. Areas of agreement: The homeostasis between the apoptotic and inflammatory processes is dynamic and controlled by pro- and anti-apoptotic mechanisms and signals, with variable balance in different areas of the RC tendons in human specimens. Areas of controversy: Apoptosis can be identified along the whole tendon, not only in the area of the lesion. Therefore, it is not necessary to undertake wide debridement of the torn edges of the tendon when undertaking a repair. Growing points: The identification of the various factors that control apoptosis and its mechanisms can help to design new treatments and exert positive effects in the recovery from tendon tears. Areas timely for developing research: Further studies are needed to produce clear guidelines to determine how to balance the apoptosis process to reduce the failed healing response found in non-traumatic RC tears.

Rotator Cuff-Sparing Approach for Antegrade Humeral Nailing With Biceps Tenodesis: A Technical Trick With Clinical Implications.

Antegrade intramedullary nails are an established, effective method of fixation for humeral shaft fractures. One significant limitation of this technique is chronic postoperative shoulder pain, which is likely related to the standard approach that involves splitting the rotator cuff to gain access to the nail starting point. Furthermore, mounting evidence suggests that both the intra-articular portion of the biceps tendon and the extra-articular portion in the bicipital groove can scar down after trauma, causing pain and limiting shoulder range of motion. We describe an approach through the rotator interval with tenodesis of the biceps tendon and resection of the intra-articular portion. Using a rotator cuff interval instead of a rotator cuff insertion approach allows access to the optimal humeral nail starting point while avoiding damage to intra-articular structures of the shoulder, potentially decreasing sources of postoperative shoulder pain.