An investigation of the congruity in geometry of the glenohumeral joint on the maximum acceptable load during pushing

Employing an arched back posture during the bench press exercise is increasingly popular. Vertical displacement of the barbell is commonly believed to be the key difference influencing strength performance between an arched and flat back bench press technique. However, comparisons between these back postures using a free weight barbell are lacking. Directly comparing performance between each posture is confounded by many variables such as proficiency and fatigue. This investigation aimed to investigate whether changing back posture alone can influence barbell kinematics, to indirectly assess potential performance differences. Twenty males performed one repetition of the bench press exercise using either an arched or flat back posture, at 25%, 50% and 75% of their one repetition maximum, in a repeated measures study design. Statistical significance was considered at p < 0.05. Changing back posture alone, reduced vertical displacement (approximately 11% average difference across all load conditions) and barbell to glenohumeral joint moment arm (approximately 20% difference) in the arched posture compared to the flat posture. These changes occurred without any specific cueing of the barbell motion and may increase the potential for lifting higher loads and decrease cumulative joint exposure. Additional cueing and training may be required to maximize the mechanical advantage available with each back posture. The arched posture appears to have an increased potential for further improvements in vertical displacement and moment arm through specific cueing. Future comparisons should consider if each back posture’s potential mechanical advantage has been maximized when assessing differences between techniques.

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Factors related to large bone defects of bipolar lesions and a high number of instability episodes with anterior glenohumeral instability

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02395-5 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Noboru Matsumura ◽

Kazuya Kaneda ◽

Satoshi Oki ◽

Hiroo Kimura ◽

Taku Suzuki ◽

...

Keyword(s):

Humeral Head ◽

Glenohumeral Joint ◽

Three Dimensional ◽

Clinical Results ◽

Bone Defects ◽

Symptom Duration ◽

Glenohumeral Instability ◽

Explanatory Variables ◽

Large Bone ◽

Large Bone Defects

Abstract Background Significant bone defects are associated with poor clinical results after surgical stabilization in cases of glenohumeral instability. Although multiple factors are thought to adversely affect enlargement of bipolar bone loss and increased shoulder instability, these factors have not been sufficiently evaluated. The purpose of this study was to identify the factors related to greater bone defects and a higher number of instability episodes in patients with glenohumeral instability. Methods A total of 120 consecutive patients with symptomatic unilateral instability of the glenohumeral joint were retrospectively reviewed. Three-dimensional surface-rendered/registered models of bilateral glenoids and proximal humeri from computed tomography data were matched by software, and the volumes of bone defects identified in the glenoid and humeral head were assessed. After relationships between objective variables and explanatory variables were evaluated using bivariate analyses, factors related to large bone defects in the glenoid and humeral head and a high number of total instability episodes and self-irreducible dislocations greater than the respective 75th percentiles were evaluated using logistic regression analyses with significant variables on bivariate analyses. Results Larger humeral head defects (P < .001) and a higher number of total instability episodes (P = .032) were found to be factors related to large glenoid defects. On the other hand, male sex (P = .014), larger glenoid defects (P = .015), and larger number of self-irreducible dislocations (P = .027) were related to large humeral head bone defects. An increased number of total instability episodes was related to longer symptom duration (P = .001) and larger glenoid defects (P = .002), and an increased number of self-irreducible dislocations was related to larger humeral head defects (P = .007). Conclusions Whereas this study showed that bipolar lesions affect the amount of bone defects reciprocally, factors related to greater bone defects differed between the glenoid and the humeral head. Glenoid defects were related to the number of total instability episodes, whereas humeral head defects were related to the number of self-irreducible dislocations.

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Cadaveric evaluation of the feasibility of glenohumeral joint denervation

Journal of Experimental Orthopaedics ◽

10.1186/s40634-020-00322-x ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Amr M. Aly

Keyword(s):

Muscle Weakness ◽

Shoulder Joint ◽

Glenohumeral Joint ◽

Axillary Nerve ◽

Low Risk ◽

Dorsal Approach ◽

Articular Branch ◽

Pectoral Nerve ◽

Teres Minor

Abstract Purpose To assess the feasibility of total shoulder denervation through two proposed incisions. Methods Total shoulder denervation was performed through an extended delta-pectoral approach and a transverse dorsal approach at the spine of the scapula. The study involved six cadavers. Course and number of articular branches from the lateral pectoral, axillary and supra-scapular nerve were documented. Results All shoulder joint articular branches were accessible through the proposed anterior and posterior approaches. The articular branch of the lateral pectoral nerve and supra scapular nerve were present in all the specimen. Axillary nerve articular branches were variable in number but when present anteriorly were proximal to the deltoid muscular branches and posteriorly proximal to the muscular branches to the teres minor. Conclusion Total glenohumeral denervation was feasible through our proposed anterior and posterior approaches. Enhanced knowledge of articular nerve branches could provide interventional targets for joint and ligament pain, with low risk of muscle weakness.

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Utilisation of musculoskeletal ultrasonography for the evaluation of septic arthritis in a patient presenting to the emergency department with fever during the era of COVID-19

BMJ Case Reports ◽

10.1136/bcr-2021-242370 ◽

2021 ◽

Vol 14 (4) ◽

pp. e242370

Author(s):

Jiodany Perez ◽

Stefani Sorensen ◽

Michael Rosselli

Keyword(s):

Emergency Department ◽

Septic Arthritis ◽

Glenohumeral Joint ◽

Imaging Modality ◽

Point Of Care ◽

Significant Morbidity ◽

Anchoring Bias ◽

Septic Bursitis ◽

Musculoskeletal Ultrasonography ◽

Point Of Care Ultrasonography

Prompt recognition and treatment of septic arthritis are crucial to prevent significant morbidity and mortality in affected patients. During the current COVID-19 pandemic, anchoring bias may make an already challenging diagnosis like septic arthritis more difficult to diagnose quickly and efficiently. Musculoskeletal (MSK) point of care ultrasonography (POCUS) is an imaging modality that can be used to quickly and efficiently obtain objective findings that may help a clinician establish the diagnosis of septic arthritis. We report a case where MSK POCUS was a key element in establishing the diagnosis of glenohumeral joint septic arthritis and subdeltoid septic bursitis for a patient that presented to the emergency department with a fever during the era of the COVID-19 pandemic.

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Hyperlipidemia Is a Risk Factor of Adhesive Capsulitis: Real-World Evidence Using the Taiwanese National Health Insurance Research Database

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967120986808 ◽

2021 ◽

Vol 9 (4) ◽

pp. 232596712098680

Author(s):

Jr-Yi Wang ◽

Chen-Kun Liaw ◽

Chi-Chang Huang ◽

Tsan-Hon Liou ◽

Hui-Wen Lin ◽

...

Keyword(s):

Risk Factor ◽

Health Insurance ◽

Propensity Score ◽

National Health Insurance ◽

National Health ◽

Glenohumeral Joint ◽

Adhesive Capsulitis ◽

Small Sample ◽

Research Database ◽

Statin Use

Background: Patients with adhesive capsulitis are evaluated for pain and progressive contracture of the glenohumeral joint. Whether endocrine, immune, or inflammatory processes are involved in its definite pathogenesis is still under debate. Some cross-sectional studies with a small sample size have noted that hyperlipidemia is a possible risk factor for frozen shoulders. Purpose/Hypothesis: The purpose was to conduct a longitudinal population-based study to investigate the risk of adhesive capsulitis among patients with hyperlipidemia. It was hypothesized that patients with hyperlipidemia would have a higher risk of adhesive capsulitis and that the use of statin drugs could reduce the rate. Study Design: Cohort study; Level of evidence, 3. Methods: Using data from the National Health Insurance Research Database (NHIRD) of Taiwan, the authors obtained the records of patients with hyperlipidemia who received a diagnosis between 2004 and 2005 and were followed up until the end of 2010. The control cohort comprised age- and sex-matched patients without hyperlipidemia. Propensity score matching was performed for the other comorbidities. A Cox multivariate proportional hazards model was applied to analyze the risk factors of adhesive capsulitis. The hazard ratio (HR) and adjusted HR were estimated between the study and control cohorts after adjustment for confounders. The effects of statin use on adhesive capsulitis risk were also analyzed. Results: The NHIRD records of 28,748 patients and 114,992 propensity score–matched controls were evaluated. A higher incidence rate of adhesive capsulitis was revealed in the hyperlipidemia cohort, with a crude HR of 1.70 (95% CI, 1.61-1.79; P < .001) and adjusted HR of 1.50 (95% CI, 1.41-1.59; P < .001). Patients with hyperlipidemia who used a statin still had higher crude and adjusted HRs compared with controls. Statin use did not exert protective effects on patients with hyperlipidemia. Conclusion: Patients with hyperlipidemia had a 1.5-fold higher risk of adhesive capsulitis than did healthy controls. Statin use did not provide protection against adhesive capsulitis in patients with hyperlipidemia.

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The Evolution and Role of the Bursal Acromial Reconstruction

Video Journal of Sports Medicine ◽

10.1177/26350254211001367 ◽

2021 ◽

Vol 1 (2) ◽

pp. 263502542110013

Author(s):

Daniel M. Curtis ◽

W. Michael Pullen ◽

Kevin Helenius ◽

Michael T. Freehill

Keyword(s):

Glenohumeral Joint ◽

Total Shoulder Arthroplasty ◽

Treatment Options ◽

Clinical Problem ◽

Clinical Results ◽

Rotator Cuff Tears ◽

Subacromial Space ◽

Promising Alternative ◽

Diagnostic Arthroscopy ◽

Superior Capsular Reconstruction

Background: Massive, irreparable rotator cuff tears (RCTs) remain a challenging clinical problem with numerous described treatment options. Bursal acromial reconstruction (BAR) represents a promising and evolving technique for a subset of patients with irreparable RCTs. Indications: BAR is indicated for patients with massive, irreparable RCTs with a primary complaint of pain, well-compensated shoulder function, and minimal radiographic degenerative changes of the glenohumeral joint as an alternative to reverse total shoulder arthroplasty or superior capsular reconstruction. Technique Description: Positioning per surgeon preference and diagnostic arthroscopy is performed. Subacromial decompression with a minimal and gentle acromioplasty is performed, followed by assessment of RCT repairability. If the tear is deemed irreparable, acromial measurements in the medial-lateral and anterior-posterior dimensions are obtained. Two pieces of acellular dermal allograft are cut to the acromial dimensions and affixed together using fibrin glue. The reactive side (facing the acromion), medial, and anterior sides of the graft are labeled. Two suture tapes are passed through the corners of the graft and self-locked and run diagonally in a cruciate configuration using an antegrade suture passer. Medial and lateral #2 fiberwire sutures are placed in a luggage-tag configuration. Neviaser (posterior), middle, and anterior acromioclavicular joint portals are created for medial sided suture passage. Medial graft sutures are shuttled through the respective medial portals and the graft is pulled into the subacromial space. The lateral sutures are then removed from percutaneous posterolateral, middle lateral, and anterolateral portals along the acromial edge. Medial sutures are retrieved using a suture grasper subcutaneously on top of the acromion through the percutaneous lateral portals. The sutures are tied through the lateral portals, starting with the medial-lateral sutures, and the knots are buried. Postoperatively, patients are progressed through passive, active-assisted, and active range of motion between weeks 2 and 6 and strengthening is progressed at 6 weeks. Results: Clinical results are lacking in the literature, but anecdotal results in our institution have demonstrated promising early outcomes. Discussion/Conclusion: BAR represents a promising alternative in the array of surgical options for treatment of irreparable RCTs.

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Functional cortical changes associated with shoulder instability – a systematic review

Shoulder & Elbow ◽

10.1177/17585732211019016 ◽

2021 ◽

pp. 175857322110190

Author(s):

Morissa F Livett ◽

Deborah Williams ◽

Hayley Potter ◽

Melinda Cairns

Keyword(s):

Systematic Review ◽

Joint Instability ◽

Glenohumeral Joint ◽

Controlled Trials ◽

Cochrane Central Register ◽

Cortical Function ◽

High Quality Research ◽

Central Register ◽

Rehabilitative Measures ◽

Randomised Controlled

Background Glenohumeral joint instability is associated with structural deficits and/or alterations in sensory and motor processing; however, a proportion of patients with glenohumeral joint instability fail to respond to surgical and rehabilitative measures. This systematic review aimed to establish if functional cortical changes occur in patients with glenohumeral joint instability. Methods AMED, CINAHL, Cochrane Central Register of Controlled Trials, Embase, Medline, PEDro, Pubmed, PsychINFO and Scopus were searched from inception to 17 March 2021. Randomised controlled trials and non-randomised trials were included and quality was appraised using the Downs and Black tool. Results One thousand two hundred seventy-nine records were identified of which five were included in the review. All studies showed altered cortical function when comparing instability patients with healthy controls and included areas associated with higher cortical functions. Discussion The findings of this systematic review offer some insight as to why interventions addressing peripheral pathoanatomical factors in patients with glenohumeral joint instability may fail in some cases due to functional cortical changes. However, data are of moderate to high risk of bias. Further high-quality research is required to ascertain the degree of functional cortical changes associated with the type and duration of glenohumeral joint instability.

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