The rotator cuff, comprising the subscapularis, supraspinatus, infraspinatus, and teres minor muscles, plays a crucial role in stabilizing the glenohumeral joint by securing the head of the humerus within the glenoid cavity of the scapula. The tendinous insertions of these muscles generate tension within the capsule, enhancing joint stability during muscular activity. The rotator cuff is susceptible to damage from disease, injury, or trauma, which can result in tears or ruptures of one or more tendons. The evaluation of the infraspinatus muscle and tendon is vital for diagnosing and managing various shoulder pathologies. Accurate imaging to determine the specific muscle involvement and injury severity significantly impacts treatment decisions. Diagnostic musculoskeletal ultrasound (MSK-US) has emerged as a valuable tool for assessing the infraspinatus muscle and tendon, offering real-time, dynamic assessment capabilities essential for precise diagnosis and effective rehabilitation planning. This article reviews the utility and advantages of MSK-US in evaluating the infraspinatus muscle and tendon, emphasizing technique specifics, diagnostic accuracy, and comparative efficacy against other imaging modalities. It details a systematic approach to the ultrasound examination technique for the infraspinatus, including patient positioning and identification of common pathologies such as tears, tendinopathy, and calcifications. With recent advancements in transducer strength, image resolution, and operator training, ultrasound serves as an excellent alternative imaging modality for diagnosing rotator cuff tears. This article aims to equip rehabilitation professionals with a comprehensive understanding of MSK-US as a diagnostic tool for the infraspinatus, promoting more precise diagnosis, treatment planning and improved patient outcomes.

UNASSIGNED: In 2020, the American Society of Shoulder and Elbow Therapists (ASSET) published an evidence-based consensus statement outlining postoperative rehabilitation guidelines following anatomic total shoulder arthroplasty (TSA).
UNASSIGNED: The purpose of this study was to (1) quantify the variability in online anatomic TSA rehabilitation protocols, and (2) assess their congruence with the ASSET consensus guidelines.
UNASSIGNED: This study was a cross-sectional investigation of publicly available, online rehabilitation protocols for anatomic TSA. A web-based search was conducted in April 2022 of publicly available rehabilitation protocols for TSA. Each collected protocol was independently reviewed by two authors to identify recommendations regarding immobilization, initiation, and progression of passive (PROM) and active range of motion (AROM), as well as the initiation and progression of strengthening and post-operative exercises and activities. The time to initiation of various components of rehabilitation was recorded as the time at which the activity or motion threshold was permitted by the protocol. Comparisons between ASSET start dates and mean start dates from included protocols were performed.
UNASSIGNED: Of the 191 academic institutions included, 46 (24.08%) had publicly available protocols online, and a total of 91 unique protocols were included in the final analysis. There were large variations seen among included protocols for the duration and type of immobilization post-operatively, as well as for the initiation of early stretching, PROM, AROM, resistance exercises, and return to sport. Of the 37 recommendations reported by both the ASSET and included protocols, 31 (83.78%) were found to be significantly different between groups (p\\<0.05).
UNASSIGNED: Considerable variability was found among online post-operative protocols for TSA with substantial deviation from the ASSET guidelines. These findings highlight the lack of standardization in rehabilitation protocols following anatomic TSA.
UNASSIGNED: 3b.

UNASSIGNED: Type 2 diabetes mellitus (T2DM) is a prevalent metabolic disorder with systemic implications, potentially affecting musculoskeletal health. This study aimed to assess shoulder muscle strength and joint repositioning accuracy in individuals with T2DM, exploring potential correlations and shedding light on the musculoskeletal consequences of the condition. The objectives were two-fold: (1) to assess and compare shoulder strength and joint repositioning accuracy between individuals with T2DM and asymptomatic counterparts, and (2) to examine the correlation between shoulder strength and joint repositioning accuracy in individuals with T2DM.
UNASSIGNED: A cross-sectional study enrolled 172 participants using the convenience sampling method, including 86 individuals with T2DM and an age-matched asymptomatic group (n = 86). Shoulder strength was assessed using a handheld dynamometer, while joint repositioning accuracy was evaluated with an electronic digital inclinometer.
UNASSIGNED: Individuals with T2DM exhibited reduced shoulder muscle strength compared to asymptomatic individuals (p < 0.001). Additionally, joint repositioning accuracy was significantly lower in the T2DM group (p < 0.001). Negative correlations were observed between shoulder strength and joint repositioning accuracy in various directions (ranging from -0.29 to -0.46, p < 0.001), indicating that higher muscle strength was associated with improved joint repositioning accuracy in individuals with T2DM.
UNASSIGNED: This study highlights the significant impact of T2DM on shoulder muscle strength and joint repositioning accuracy. Reduced strength and impaired accuracy are evident in individuals with T2DM, emphasizing the importance of addressing musculoskeletal aspects in diabetes management. The negative correlations suggest that enhancing shoulder muscle strength may lead to improved joint repositioning accuracy, potentially contributing to enhanced physical functioning in this population.

Round-shoulder posture (RSP) is a common postural condition, characterized by protraction, downward rotation, anterior tilting and internal rotation of the scapula. RSP can lead to shoulder dysfunction. Different methods have been proposed for rehabilitating and correcting the altered posture in RSP including stretching, strengthening exercises, and shoulder brace or taping. However, the findings are controversial and studies are ongoing to develop more effective method. The present study is aimed at investigating the effects of scapular posterior tilting (SPT) exercise in different support positions on scapular muscle activities in men and women with RSP. In a prospective observational clinical study, we assessed demographic, basic clinical parameters and study variables of the subjects with RSP (n = 20) (men/women = 9/11) attending Daegu University in Gyeongsan, South Korea. To do so, we compared electromyographic (EMG) activities of lower trapezius and serratus anterior muscles between men and women with RSP during SPT exercise on four different support surfaces to determine any difference in the EMG activities. The results revealed that women showed significant differences in EMG activities in the lower and left upper trapezius and serratus anterior muscles, while men showed significant differences in EMG activity only in the lower trapezius muscle during SPT exercise on four different surfaces (P < 0.05). The post-hoc analysis revealed significantly greater EMG activity values in the lower trapezius and serratus anterior muscles during SPT exercise on the upper body unstable surface and whole-body unstable surface (p < 0.05). Independent t-tests after the Bonferroni correction showed no significant differences in muscle activities between men and women on the four different surfaces (p > 0.0125).

The supraspinatus tendon is one of the most involved tendons in the development of shoulder pain. Extracorporeal shockwave therapy (ESWT) has been recognized as a valid and safe treatment. Sometimes the symptoms cannot be relieved, or a relapse develops, affecting the patient\'s quality of life. Therefore, a prediction protocol could be a powerful tool aiding our clinical decisions. An artificial neural network was run, in particular a multilayer perceptron model incorporating input information such as the VAS and Constant-Murley score, administered at T0 and at T1 after six months. It showed a model sensitivity of 80.7%, and the area under the ROC curve was 0.701, which demonstrates good discrimination. The aim of our study was to identify predictive factors for minimal clinically successful therapy (MCST), defined as a reduction of ≥40% in VAS score at T1 following ESWT for chronic non-calcific supraspinatus tendinopathy (SNCCT). From the male gender, we expect greater and more frequent clinical success. The more severe the patient\'s initial condition, the greater the possibility that clinical success will decrease. The Constant and Murley score, Roles and Maudsley score, and VAS are not just evaluation tools to verify an improvement; they are also prognostic factors to be taken into consideration in the assessment of achieving clinical success. Due to the lower clinical improvement observed in older patients and those with worse clinical and functional scales, it would be preferable to also provide these patients with the possibility of combined treatments. The ANN predictive model is reasonable and accurate in studying the influence of prognostic factors and achieving clinical success in patients with chronic non-calcific tendinopathy of the supraspinatus treated with ESWT.

Background  Glenoid version refers to the angle subtended by the glenoid with the scapula. On average, it is 0 ± 10 degrees with a slight propensity toward retroversion. Numerous factors such the dominance(handedness), gender, ethnicity, and pathology are known to affect version. Version has important consequences on the biomechanics of the shoulder joint and is altered in those with arthritis and shoulder joint instability. Aim  Our study aimed to determine the normal range of glenoid version in the population. Further, we aim to assess the relationship between gender and version. Settings and Design  We conducted a retrospective observational study in a tertiary referral hospital with a target sample size of 200 shoulders. Methods and Materials  The computed tomography images were retrospectively reviewed to determine the scapular shape and the glenoid version angle. Statistical Analysis  Statistical analysis was done using SPSS v.22 software with p -value less than 0.05 considered as significant. Results  The mean age of the individuals in our study was 44 years. In our study, irrespective of gender, most individuals had some degree of anteversion and males had lower degree of anteversion. Previous studies have shown that most normal individuals usually have retroverted shoulder joints. The mean glenoid version was significantly lower in the right than in the left shoulder and males had significantly lower mean glenoid version than females in both shoulders. Most individuals in our study had a flat scapular spine. Conclusion  This study shows that the Indian population may have a slight propensity toward anteversion and this has an important bearing on shoulder arthroplasty. Further, this study shows that significantly lower degrees of version are found on the right side and that the degree of version is significantly lower in males. Understanding the role of glenoid version in shoulder biomechanics will go a long way in the early identification of pathology, the preoperative planning of shoulder arthroplasty, and the operative restoration of a functional shoulder joint.

Objective  To investigate whether patients undergoing anatomic total shoulder arthroplasty (ATSA) between January and March 2020 experienced different postoperative outcomes than patients in 2019. We hypothesized that patients in 2020 would have less access to physical therapy (PT) and experience different postoperative outcomes. Methods  Records from patients who received ATSA between January 1st, 2019, and March 17th, 2019, and January 1st, 2020, to March 17th, 2020, were analyzed. Patient data, including demographic information, range of motion (ROM), strength, and PT was collected and compared between the two groups. The 2020 patients were contacted by phone during October 2022 and patient-reported metrics were gathered. Results  The present study identified 24 patients in 2019 and 27 patients in 2020 who underwent ATSA during the specified time frame and had a minimum 1-year follow-up. Patients in 2019 experienced improvements in forward elevation (FE) ROM (125.4° to 146.7°; p  = 0.008), external rotation (ER; 33.0° to 47.7°; p  < 0.001), and internal rotation (IR; S1 to L4; p  = 0.019). Patients in 2020 also experienced significant improvements in FE (120.2° to 141.1°; p  = 0.009), ER (32.9° to 42.0°; p  = 0.037), and IR (S1 to L3; p  = 0.002). Patients in 2020 terminated PT earlier (2019: 125.8 days; 2020: 91.1 days; p  = 0.046) and completed fewer sessions (2019: 21.4 sessions; 2020: 13.1 sessions; p  = 0.003). At the final follow-up, patients in 2020 reported an average Visual Analogue Scale (VAS) pain score of 1.67 ± 1.1. Conclusion  Despite decreased PT, patients who underwent ATSA in 2020 had significant improvements in ROM and strength and were comparable to patients in 2019.

UNASSIGNED: Glenoid bone loss (GBL) is common in patients with shoulder instability and plays a major role in surgical decision-making. While a plethora of GBL estimation methods exist, all of which present specific challenges, recent studies have developed simple linear formulas estimating GBL based on glenoid height.
UNASSIGNED: To assess the correlation between glenoid height and width, and to develop specific formulas based on age and sex to calculate the native glenoid width in the Lebanese population.
UNASSIGNED: Cross-sectional study; Level of evidence, 3.
UNASSIGNED: Computed tomography scans for 202 normal shoulders were extracted from our database. The glenoids were reconstructed in 3 dimensions and their width and height were measured. Glenoid width and height were compared between male and female groups. Correlation analysis was also performed on the width, height, age, and body mass index. Formulas estimating glenoid width were developed using regression analysis including all variables significantly influencing the model. Results were then compared with the values calculated using previously published formulas to determine the external validity when using linear formulas to estimate GBL.
UNASSIGNED: Significant differences were found between men and women. Regression analysis found that glenoid height and width strongly influenced the model, and that age showed a weak but significant correlation; therefore, the following 2 sex-specific formulas were developed: width (mm) = 6.1 + 0.51 ×height+ 0.03 ×age, and width (mm) = 4.55 + 0.51 ×height+ 0.03 ×age, in men and women, respectively. The values yielded from the formulas developed in this study and the true width significantly differed from those calculated from previous reports.
UNASSIGNED: A strong correlation was found between glenoid height and width in a the Lebanese population and demonstrated that glenoid width can be accurately calculated based on the glenoid height and patient\'s age and sex using the following simplified formulas: width (mm) = 6 + 0.5 ×height+ 0.03 ×age, and width (mm) = 4.5 + 0.5 ×height+ 0.03 ×age, in men and women, respectively.

This study aimed to determine the absolute and relative reliability of concentric and eccentric flexion, extension, horizontal abduction, and adduction movements of the shoulder using a functional electromechanical dynamometer (FEMD). Forty-three active male university students (23.51 ± 4.72 years) were examined for concentric and eccentric strength of shoulder flexion, extension, horizontal abduction, and horizontal adduction with an isokinetic test at 0.80 m·s-1. Relative reliability was determined by intraclass correlation coefficients (ICCs) with 95% confidence intervals. Absolute reliability was quantified by the standard error of measurement (SEM) and coefficient of variation (CV). Reliability was very high to extremely high for all movements on concentric and eccentric strength measurements (ICC: 0.76-0.94, SEM: 0.63-6.57%, CV: 9.40-19.63%). The results of this study provide compelling evidence for the absolute and relative reliability of concentric and eccentric flexion, extension, horizontal abduction, and horizontal adduction shoulder isokinetic strength tests in asymptomatic adults. The mean concentric force was the most reliable strength value for all tests.

The integration of artificial intelligence (AI) models in the classification of electromyographic (EMG) signals represents a significant advancement in the design of control systems for prostheses. This study explores the development of a portable system that classifies the electrical activity of three shoulder muscles in real time for actuator control, marking a milestone in the autonomy of prosthetic devices. Utilizing low-power microcontrollers, the system ensures continuous EMG signal recording, enhancing user mobility. Focusing on a case study-a 42-year-old man with left shoulder disarticulation-EMG activity was recorded over two days using a specifically designed electronic board. Data processing was performed using the Edge Impulse platform, renowned for its effectiveness in implementing AI on edge devices. The first day was dedicated to a training session with 150 repetitions spread across 30 trials and three different movements. Based on these data, the second day tested the AI model\'s ability to classify EMG signals in new movement executions in real time. The results demonstrate the potential of portable AI-based systems for prosthetic control, offering accurate and swift EMG signal classification that enhances prosthetic user functionality and experience. This study not only underscores the feasibility of real-time EMG signal classification but also paves the way for future research on practical applications and improvements in the quality of life for prosthetic users.