Rotator Cuff Tears In Patients Research Articles

Subacromial bursa in patients with rotator cuff tear with or without adhesive capsulitis exhibits a differential transcriptome with potential molecular biomarkers

BackgroundAlthough adhesive capsulitis (AC) is a common condition, the pathological mechanisms remain understudied. The purpose of our research was to evaluate variations in gene expression across the entire genome in the subacromial bursa tissue of individuals with rotator cuff tears (RCT), with or without AC, and to explore the factors that may influence the occurrence and progression of AC. MethodsTranscription profiles of subacromial bursa samples from 12 RCT patients, of whom 6 had also AC, were evaluated. Data were generated using RNA-seq. DESeq2 was utilized to identify the differentially expressed genes (DEGs) in both groups. In order to conduct a more in-depth examination of the DEGs, we performed Gene Ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. A network of interactions between proteins was built, and the central genes were determined using Cytoscape. The hub genes were confirmed through qRT-PCR and immunohistochemistry. Results324 of the 16,251 detected genes were identified as DEGs. Analysis of GO functional enrichment showed that the DEGs were enriched in domains of biological process, molecule function and cellular component. Analysis of KEGG pathways revealed enrichment of DEGs in pathways like IL-17 signaling and ECM-receptor interaction. We verified that the association between AC and the increase in expression of the PPI network hub genes. ConclusionThis study investigated the transcriptome differences of subacromial bursa in RCT patients with or without AC. Using bioinformatics technology, we identified the DEGs and screened out the hub genes. The research enhanced the data on gene expression profiles of DEGs in the subacromial bursa tissue of patients with RCT, offering fresh perspectives on the regulation of gene transcription.

A new method of the dynamic assessment of the supraspinatus using ultrasonography

ObjectiveWe devised a new dynamic assessment of the supraspinatus (DAS) using ultrasonography. The objectives of this study are as follows: 1. to verify the moving distance of the supraspinatus using ultrasonography in the cadaveric shoulders; 2. to evaluate the reliability of DAS in patients with rotator cuff tear (RCT) and investigate the correlation between DAS and magnetic resonance imaging (MRI) assessments. MethodsIn Part 1, the supraspinatus in both shoulders of one cadaveric specimen was pulled laterally by 5 mm and 10 mm. In the ultrasonographic movie of the supraspinatus, the moving distances of a placed marker and a representative speckle which was visually identified as a high-intensity dot with the longest track were measured. In Part 2, among 62 RCT shoulders we verified the interrater agreement of DAS and correlation between DAS and MRI findings of RCT size and muscle atrophy. ResultsIn Part 1, during the supraspinatus traction, the moving distances of the marker and speckle were almost same; 1.07–2.68 mm and 1.60–2.67 mm, respectively (the pulled distance was 5 mm), 3.95–5.35 mm and 3.59–5.60 mm (the pulled distance was 10 mm). In Part 2, DAS showed a high interrater agreement of 0.74 in the kappa coefficients. DAS showed no correlations with tear size and atrophy, respectively (Spearman's rank correlation coefficient (ρ): 0.14 (p = 0.35) and 0.13 (p = 0.29)). ConclusionDAS can reliably demonstrate dynamic aspects of the supraspinatus in RCT patients, which have been lacked in static imaging assessments as MRI.

Ultrasonic shear wave elastography predicts the quality of the residual tendon before the rotator cuff repair

Background and purposeEffective evaluation of rotator cuff tear residual tendon quality is the key to surgical repair. However, until now, the evaluation of rotator cuff tissue by ultrasonic shear wave elasticity (SWE) has been controversial. This prospective study analyzed the association between preoperative SWE and arthroscopic residual tendon quality scores.MethodsThe shear wave velocity (SWV) of the deltoid muscle, the supraspinatus tendon, and the supraspinatus muscle were measured in full-thickness rotator cuff tear patients. Tendon quality was scored according to tear size, tendon margin, tendon thickness, and footprint coverage during arthroscopy. The arthroscopic scores were used as the gold standard, and the SWV ratio of tendon and muscle (supraspinatus tendon/deltoid and supraspinatus muscle/deltoid) were calculated and correlated with the arthroscopic scores.ResultEighty-nine patients (129 shoulders) were enrolled, including 89 operation shoulders and 40 control shoulders. In the group of operation shoulders, both the SWV ratios of tendon (SWV-RT) and the SWV ratio of muscle (SWV-RM) were negatively correlated with arthroscopic scores (The correlation coefficient (R) ranged from -0.722 to -0.884 and -0.569 to -0.689). The SWV-RT and SWV-RM of the operation shoulders were significantly lower than that of the control shoulders (p < 0.05).ConclusionSWE could be used to predict the quality of the residual tendon before the rotator cuff repair. SWV of the supraspinatus tendon and muscle was a useful parameter to predict the quality of the residual tendon.Critical relevance statementMeasuring the shear wave velocity of the supraspinatus tendon and muscle with SWE is useful for predicting the quality of the residual tendon which is one of the key factors for a successful rotator cuff repair.Key points• Evaluating the quality of the residual tendon is important before surgery.• Elasticity measurements were negatively correlated with the arthroscopic score.• SWE is useful for predicting the quality of the residual tendon.Graphical

The influence of rotator cuff tear type and weight bearing on shoulder biomechanics in an ex vivo simulator experiment

Glenohumeral biomechanics after rotator cuff (RC) tears have not been fully elucidated. This study aimed to investigate the muscle compensatory mechanism in weight-bearing shoulders with RC tears and asses the induced pathomechanics (i.e., glenohumeral translation, joint instability, center of force (CoF), joint reaction force).An experimental, glenohumeral simulator with muscle-mimicking cable system was used to simulate 30° scaption motion. Eight fresh-frozen shoulders were prepared and mounted in the simulator. Specimen-specific scapular anthropometry was used to test six RC tear types, with intact RC serving as the control, and three weight-bearing loads, with the non-weight-bearing condition serving as the control. Glenohumeral translation was calculated using instantaneous helical axis. CoF, muscle forces, and joint reaction forces were measured using force sensors integrated into the simulator. Linear mixed effects models (RC tear type and weight-bearing) with random effects (specimen and sex) were used to assess differences in glenohumeral biomechanics.RC tears did not change the glenohumeral translation (p > 0.05) but shifted the CoF superiorly (p ≤ 0.005). Glenohumeral translation and joint reaction forces increased with increasing weight bearing (p < 0.001). RC and deltoid muscle forces increased with the presence of RC tears (p ≤ 0.046) and increased weight bearing (p ≤ 0.042).The synergistic muscles compensated for the torn RC tendons, and the glenohumeral translation remained comparable to that for the intact RC tendons. However, in RC tears, the more superior CoF was close to where glenoid erosion occurs in RC tear patients with secondary osteoarthritis. These findings underscore the importance of early detection and precise management of RC tears.

Rotator Cuff Tendinopathy: Pathways of Apoptosis.

Rotator cuff repair is usually successful, but retear is not uncommon. It has been previously identified that there is a higher incidence of apoptosis in the edges of the torn supraspinatus tendon. A prospective cohort study was conducted with 28 patients-14 rotator cuff tear patients, 5 instability patients, and 9 Anterior cruciate ligament reconstruction patients to determine whether there was any increase in several genes implicated in apoptosis, including Fas receptor (FasR), Fas ligand, Aifm-1, Bcl-2, Fadd, Bax, and caspase-3. There was a significant expression of Bax (P=0.2) and FasR (P=0.005) in the edges of torn supraspinatus tendons, and in intact subscapularis tendons, there was a significant expression of caspase-3 (P=0.02) compared with samples from the torn supraspinatus tendon (P=0.04). The cytochrome c pathway, with its subsequent activation of caspase-3, as well as the TRAIL-receptor signaling pathway involving FasR have both been implicated. The elevated expression of Bax supported the model that the Bax to Bcl-2 expression ratio represents a cell death switch. The elevated expression of Bax in the intact subscapularis tissue from rotator cuff tear patients also may confirm that tendinopathy is an ongoing molecular process.

Factors associated with genetic markers for rotator cuff disease in patients with atraumatic rotator cuff tears.

For atraumatic rotator cuff tears, genetics contributes to symptomatic tear risk and may influence rotator cuff healing after surgical repair. But little is known about how genetic factors influence rotator cuff tear patient characteristics at presentation. We collected saliva samples for genotyping from atraumatic rotator cuff tear patients. We examined nine single nucleotide polymorphisms (SNPs) associated with cuff tears in prior literature. We estimated associations of SNP dosage with 1) age at tear diagnosis, 2) bilateral atraumatic tear prevalence, and 3) tear size. Linear regression was used to estimate associations with diagnosis age adjusted for sex and principal components. Logistic regression and ordinal logistic regression were used to estimate associations with bilateral tear prevalence and tear size category, respectively, adjusting for age, sex, and principal components. Of 344 eligible patients, 336 provided sufficient samples for genotyping. Median age at tear diagnosis was 61, 22% (N=74) had bilateral atraumatic tears, and 9% (N=29) had massive tears. SNP rs13107325 in the SLC39A8 gene and rs11850957 in the STXBP6 gene were associated with younger diagnosis age even after accounting for multiple comparisons (rs13107325: -4 years, 95%CI=-6.5, -1.4; rs11850957: -2.7 years, 95%CI=-4.3, -1.1). No other significant associations were observed with diagnosis age, tear size, or bilateral tear prevalence. SLC39A8 encodes a Mn transporter. STXBP6 may play a role in inflammatory responses by altering phagocytosis and antigen presentation of monocytes and macrophages. Further research is needed to determine if genetic markers can be used alongside patient characteristics to aid in identifying optimal surgical repair candidates. This article is protected by copyright. All rights reserved.

ROTATOR CUFF TEAR IN FRACTURE SHOULDER DISLOCATION

IntroductionWe aim to assess whether radiographic characteristics of the greater tuberosity fragment can predict rotator cuff tears inpatients with anterior shoulder dislocations combined with an isolated fracture of the greater tuberosity.MethodsA retrospective single-centre case series of 61 consecutive patients that presented with anterior shoulder dislocations combined with an isolated fracture of the greater tuberosity between January 2018 and July 2022. Inclusion criteria: patients with atraumatic anterior shoulder dislocation associated with an isolated fracture of the greater tuberosity with a minimum follow-up of 3-months. Exclusion criteria: patients with other fractures of the proximal humerus or glenoid. Rotator cuff tears were diagnosed using magnetic resonance or ultrasound imaging. Greater tuberosity fragment size and displacement was calculated on plain radiographs using validated methods.ResultsThe case series was composed of 22 men and 39 women with a mean age of 65 years (29 - 91 years). The mean follow-up was 15months and median follow up 8.5 months (3 – 60 months). A rotator cuff tear was diagnosed in 14 patients (16%) and involved the supraspinatus (13), infraspinatus (4) and subscapularis (2). Full-thickness tears occurred in 6 patients and partial-thickness tears in 8patients. The mean time from initial injury to rotator cuff tear diagnosis was 5 months (2 – 22 months).The mean greater tuberosity fragment length was 23.4 mm in rotator cuff tear patients versus 32.6 mm in those without a tear (p = 0.006, CI: -15 - -2). The mean greater tuberosityfragment width was 11.1 mm in rotator cuff tear patients versus 17.8 mm in those without a tear (p = 0.0004, CI: -10 - -2). There was no significant difference in the super inferior and anteroposterior fragment displacement between the two groups.ConclusionIn patients with shoulder dislocations combined with an isolated fracture of the greater tuberosity, rotator cuff tears are associated with a smaller sized greater tuberosity fragment.

Local Injection of Rapamycin-Loaded Pcl-Peg Nanoparticles for Enhanced Tendon Healing in Rotator Cuff Tears via Simultaneously Reducing Fatty Infiltration and Drug Toxicity.

As a common cause of shoulder pain, rotator cuff tears (RCTs) are difficult to treat clinically because of their unsatisfactory prognosis due to the fatty infiltration caused by muscle-derived stem cells (MDSCs). Previous studies have found that rapamycin (RAPA) can inhibit fatty infiltration. However, systemic administration of RAPA may cause complications such as infection and nausea, while local administration of RAPA may lead to the cytotoxicity of tendon cells, affecting the healing of rotator cuffs. In this study, biocompatible and clinically approved polycaprolactone-polyethylene glycol (PCL-PEG) is formulated into an injectable nanoparticle for the sustained release of RAPA. The results indicate that the RAPA/PCL-PEG nanoparticles (NPs) can efficiently prolong the release of RAPA and significantly reduce the cytotoxicity of tendon cells caused by RAPA. Thestudy of the fatty infiltration model in rats with delayed rotator cuff repair shows that weekly intraarticular injection of RAPA/PCL-PEG NPs can more effectively reduce the fatty infiltration and muscle atrophy of rat rotator cuffs and leads to better mechanical properties and gait improvements than a daily intraarticular injection of RAPA. These findings imply that local injection of RAPA/PCL-PEG NPs in the shoulder joints can be a potential clinical option for RCTs patients with fatty infiltration.

Operative Management of Rotator Cuff Tears: Identifying Disparities in Access on a National Level.

The purpose of this study was to identify nationwide disparities in the rates of operative management of rotator cuff tears based on race, ethnicity, insurance type, and socioeconomic status. Patients diagnosed with a full or partial rotator cuff tear from 2006-2014 were identified in the Healthcare Cost and Utilization Project's National Inpatient Sample database using International Classification of Diseases, Ninth Revision (ICD-9) diagnosis codes. Bivariate analysis using chi-square tests and adjusted, multivariable logistic regression models were used to evaluate differences in the rates of operative versus non-operative management for rotator cuff tears. This study included 46,167 patients. When compared with white patients, adjusted analysis showed that minority race and ethnicity were associated with lower rates of operative management for Black [adjusted odds ratio (AOR): 0.31, 95% confidence interval (CI): 0.29-0.33; p < 0.001], Hispanic [AOR: 0.49, 95% CI: 0.45-0.52; p < 0.001], Asian or Pacific Islander [AOR: 0.72, 95% CI: 0.61-0.84; p < 0.001], and Native American patients [AOR: 0.65, 95% CI: 0.50-0.86; p = 0.002]. In comparison to privately insured patients, our analysis also found that self-payers [AOR: 0.08, 95% CI: 0.07-0.10; p < 0.001], Medicare beneficiaries [AOR: 0.76, 95% CI: 0.72-0.81; p < 0.001], and Medicaid beneficiaries [AOR: 0.33, 95% CI: 0.30-0.36; p < 0.001] had lower odds of receiving surgical intervention. Additionally, relative to those in the bottom income quartile, patients in all other quartiles experienced nominally higher rates of operative repair; these differences were statistically significant for the second quartile [AOR: 1.09, 95% CI: 1.03-1.16; p = 0.004]. There are significant nationwide disparities in the likelihood of receiving operative management for rotator cuff tear patients of differing race/ethnicity, payer status, and socioeconomic status. Further investigation is needed to fully understand and address causes of these discrepancies to optimize care pathways.

Mini open anterolateral rotator cuff tear repair with the help of suture anchor

Background: It is generally accepted that mini open rotator cuff tear repair with the help of suture anchor gives satisfactory results in the long term, although most studies have so far shown a fairly high rate of good structural and functional outcome. The purpose of this study is to asses functional outcome of mini-open anterolateral rotator cuff tear repair with the help of suture anchor. Method: The 30 consecutive rotator cuff tear patients were selected from outpatient department at medical college. All patients were diagnosed with full thickness rotator cuff tear and subsequently treated with mini-open anterolateral approach technique. Each patient was clinically assessed with DASH questionnaire and constant Murley score for their satisfaction. Results: After a minimum of 12 month follow up period, the average clinical outcome scores all improved significantly at the time of final follow up. Conclusions: Patient with mini-open anterolateral rotator cuff tear repair with the help of anchor suture showed improvement in their functional outcome and range of motion. 

Application of Machine Learning Algorithms for Prognostic Assessment in Rotator Cuff Pathologies: A Clinical Data-Based Approach.

The overall aim of this proposal is to ameliorate the care of rotator cuff (RC) tear patients by applying an innovative machine learning approach for outcome prediction after arthroscopic repair. We applied state-of-the-art machine learning algorithms to evaluate the best predictors of the outcome, and 100 RC patients were evaluated at baseline (T0), after 1 month (T1), 3 months (T2), 6 months (T3), and 1 year (T4) from surgical intervention. The outcome measure was the Costant-Murley Shoulder Score, whereas age, sex, BMI, the 36-Item Short-Form Survey, the Simple Shoulder Test, the Hospital Anxiety and Depression Scale, the American Shoulder and Elbow Surgeons Score, the Oxford Shoulder Score, and the Shoulder Pain and Disability Index were considered as predictive factors. Support vector machine (SVM), k-nearest neighbors (k-NN), naïve Bayes (NB), and random forest (RF) algorithms were employed. Across all sessions, the classifiers demonstrated suboptimal performance when using both the complete and shrunken sets of features. Specifically, the logistic regression (LR) classifier achieved a mean accuracy of 46.5% ± 6%, while the random forest (RF) classifier achieved 51.25% ± 4%. For the shrunken set of features, LR obtained a mean accuracy of 48.5% ± 6%, and RF achieved 45.5% ± 4.5%. No statistical differences were found when comparing the performance metrics of ML algorithms. This study underlines the importance of extending the application of AI methods to new predictors, such as neuroimaging and kinematic data, in order to better record significant shifts in RC patients' prognosis. The data quality within the cohort could represent a limitation, since certain variables, such as smoking, diabetes, and work injury, are known to have an impact on the outcome.

Deep learning for automated measurement of CSA related acromion morphological parameters on anteroposterior radiographs

BackgroundThe Critical Shoulder Angle Related Acromion Morphological Parameter (CSA- RAMP) is a valuable tool in the analyzing the etiology of the rotator cuff tears (RCTs). However, its clinical application has been limited by the time-consuming and prone to inter- and intra-user variability of the measurement process. ObjectivesTo develop and validate a deep learning algorithm for fully automated assessment of shoulder anteroposterior radiographs associated with RCTs and calculation of CSA-RAMP. MethodsRetrospective analysis was conducted on radiographs obtained from computed tomography (CT) scans and X-rays performed between 2018 and 2020 at our institution. The development of the system involved the utilization of digitally reconstructed radiographs (DRRs) generated from each CT scan. The system's performance was evaluated by comparing it with manual and semiautomated measurements on two separate test datasets: dataset I (DRRs) and dataset II (X-rays). Standard metrics, including mean average precision (AP), were utilized to assess the segmentation performance. Additionally, the consistency among fully automated, semiautomated, and manual measurements was comprehensively evaluated using the Pearson correlation coefficient and Bland-Altman analysis. ResultsA total of 1080 DRRs generated from 120 consecutive CT scans and 159 X-ray films were included in the study. The algorithm demonstrated excellent segmentation performance, with a mean AP of 57.67 and an AP50 of 94.31. Strong inter-group correlations were observed for all CSA-RAMP measurements in both test datasets I (automated versus manual, automated versus semiautomated, and semiautomated versus manual; r = [0.990–––0.997], P < 0.001) and dataset II (r = [0.984–––0.995], P < 0.001). Bland-Altman analysis revealed low bias for all CSA-RAMP measurements in both test datasets I and II, except for CD (with a maximum bias of 2.49%). ConclusionsWe have successfully developed a fully automated algorithm capable of rapidly and accurately measuring CSA-RAMP on shoulder anteroposterior radiographs. A consistent automated CSA- RAMP measurement system may accelerate powerful and precise studies of disease biology in future large cohorts of RCTs patients.

Artificial Intelligence and Machine Learning in Rotator Cuff Tears

Rotator cuff tears (RCTs) negatively impacts patient well-being. Artificial intelligence (AI) is emerging as a promising tool in medical decision-making. Within AI, deep learning allows to autonomously solve complex tasks. This review assesses the current and potential applications of AI in the management of RCT, focusing on diagnostic utility, challenges, and future perspectives. AI demonstrates promise in RCT diagnosis, aiding clinicians in interpreting complex imaging data. Deep learning frameworks, particularly convoluted neural networks architectures, exhibit remarkable diagnostic accuracy in detecting RCTs on magnetic resonance imaging. Advanced segmentation algorithms improve anatomic visualization and surgical planning. AI-assisted radiograph interpretation proves effective in ruling out full-thickness tears. Machine learning models predict RCT diagnosis and postoperative outcomes, enhancing personalized patient care. Challenges include small data sets and classification complexities, especially for partial thickness tears. Current applications of AI in RCT management are promising yet experimental. The potential of AI to revolutionize personalized, efficient, and accurate care for RCT patients is evident. The integration of AI with clinical expertise holds potential to redefine treatment strategies and optimize patient outcomes. Further research, larger data sets, and collaborative efforts are essential to unlock the transformative impact of AI in orthopedic surgery and RCT management.

Tailored modulation of S100A1 and RASSF8 expression by butanediamide augments healing of rotator cuff tears.

This investigation sought to elucidate promising treatment modalities for rotator cuff tears (RCTs) by delving into the molecular machinations instigating the affliction. The focus was on differentially expressed genes (DEGs) linked to RCTs, and the exploration of their roles and operative pathways. DEGs were discerned from GEO datasets, followed by the establishment of a protein-protein interaction (PPI) network. Subsequently, the network's core genes were determined employing a Venn diagram. Enrichment analysis facilitated the unveiling of the biological roles and signal transduction pathways of these pivotal genes, thus shedding light on molecular strategies for RCT-targeted treatment. The Discovery Studio 2019 software was employed to sift through FDA-sanctioned drugs targeting these essential proteins. Moreover, the efficaciousness of these FDA-endorsed drugs vis-à-vis RCTs was corroborated by the construction of an in vivo animal model of the injury and the in vitro cultivation of tendon-derived stem cells. Bioinformatics outcomes revealed a significant overexpression of S100A1 and RASSF8 in RCT patients. The FDA drug repository indicated that Butanediamide has a selective affinity for S100A1 and RASSF8. Subsequent in vivo and in vitro experimentation demonstrated that Butanediamide could suppress S100A1 expression and bolster TDSC proliferation, thereby facilitating RCT healing. S100A1 and RASSF8 are pivotal genes implicated in RCTs, and their roles have been elucidated. The FDA-approved compound, Butanediamide, may represent a prospective therapeutic agent for RCTs by targeting S100A1 and RASSF8, respectively.

High-intensity interval training improves fatty infiltration in the rotator cuff through the β3 adrenergic receptor in mice

AimsRotator cuff muscle atrophy and fatty infiltration affect the clinical outcomes of rotator cuff tear patients. However, there is no effective treatment for fatty infiltration at this time. High-intensity interval training (HIIT) helps to activate beige adipose tissue. The goal of this study was to test the role of HIIT in improving muscle quality in a rotator cuff tear model via the β3 adrenergic receptor (β3AR).MethodsThree-month-old C57BL/6 J mice underwent a unilateral rotator cuff injury procedure. Mice were forced to run on a treadmill with the HIIT programme during the first to sixth weeks or seventh to 12th weeks after tendon tear surgery. To study the role of β3AR, SR59230A, a selective β3AR antagonist, was administered to mice ten minutes before each exercise through intraperitoneal injection. Supraspinatus muscle, interscapular brown fat, and inguinal subcutaneous white fat were harvested at the end of the 12th week after tendon tear and analyzed biomechanically, histologically, and biochemically.ResultsHistological analysis of supraspinatus muscle showed that HIIT improved muscle atrophy, fatty infiltration, and contractile force compared to the no exercise group. In the HIIT groups, supraspinatus muscle, interscapular brown fat, and inguinal subcutaneous white fat showed increased expression of tyrosine hydroxylase and uncoupling protein 1, and upregulated the β3AR thermogenesis pathway. However, the effect of HIIT was not present in mice injected with SR59230A, suggesting that HIIT affected muscles via β3AR.ConclusionHIIT improved supraspinatus muscle quality and function after rotator cuff tears by activating systemic sympathetic nerve fibre near adipocytes and β3AR.Cite this article: Bone Joint Res 2023;12(8):455–466.

Central sensitization syndrome in patients with rotator cuff tear: prevalence and associated factors

ABSTRACT Introduction A significant number of rotator cuff tear (RCT) patients developed chronic shoulder pain that did not correspond to physiological changes. Central sensitization syndrome (CSS) is a neurophysiological adaptation process that can result in hypersensitivity to peripheral stimuli. Although there is evidence of an association between CSS and musculoskeletal problems, no studies have focused on the association between CSS and RCT. The primary purpose of this study was to examine the prevalence of CSS in patients with RCT. The secondary purpose was to document the associated conditions and comorbidity that were associated with the CSS. Methods This was a cross-sectional study of patients with RCT who completed the Central Sensitization Inventory (CSI). Patients with score of ≥ 40/100 were considered positive for CSS. Demographic and clinical data and CSI results were collected to analyze the prevalence and associated factors of CSS in RCT patients. Results A total of 404 RCT patients were included, and the CSS prevalence was 39.4%. Compared to the non-CSS group, the CSS group had an odds ratio of 4.13 (95% CI, 2.70–6.32; p＜0.001) for ages 51–60, 3.07 (95% CI, 2.00–4.69; p＜0.001) for symptoms lasting more than 6 months, 6.08 (95% CI, 3.90–9.47; p＜0.001) for nonphysical laborers, 3.69 (95%CI, 2.42–5.61; p＜0.001) for long head of biceps (LHB) abnormality, 2.93 (95% CI, 1.93–4.45; p＜0.001) for concurrent shoulder stiffness, 4.82 (95% CI, 2.55–9.10; p＜0.001) for anxiety or panic episodes, and 2.11 (95% CI, 1.12, 4.00; p＜0.001) for depression. Conclusions The prevalence of CSS in patients with RCT was relatively high at 39.4%. The CSS was associated with higher age, female gender, and clinical findings of symptoms lasting over six months, nonphysical laborers, abnormal LHB, concurrent shoulder stiffness, anxiety, and depression.

Concordance of shoulder strength assessments using a spring balance and isometric dynamometer in patients before and after arthroscopic rotator cuff repair

Shoulder strength is an essential assessment to monitor the outcome of treatment interventions. Isometric strength assessment in the Constant Score (CS) was initially measured with a cable tensiometer or spring balance (SB). Some authors have questioned the validity of this strength assessment and the resulting CS. The purpose of this study was to investigate the concordance of strength measurements using an unsecured SB vs. isometric dynamometer and outline the impact of these methods on the CS. In the context of routine clinical examination as well as participation in a Swiss national cohort study, shoulder strength was measured to calculate baseline (before surgery) and 6-month postoperative CS in adult rotator cuff tear patients who had undergone primary arthroscopic rotator cuff repair. Measurements of each of the operated and contralateral shoulders were made per patient routinely using an unsecured SB and study-specific using an isometric dynamometer in patients with the shoulder at 90° abduction in the scapular plane. Absolute and change values of strength and CS data were presented in scatter plots and assessed using concordance correlation coefficients (CCCs) and Bland-Altman plots. Between June 2020 and October 2021, baseline strength measurements from the operated shoulder of 78 patients ranged from 0.0 to 13.6 kg with a CCC of 0.64 (P<.001) and a mean difference of 0.81 kg between the SB and dynamometer methods. There were 89 measurements of the contralateral healthy shoulder that ranged from 3.6 to 15.6 kg; CCC and mean strength difference were 0.76 (P<.001) and 0.70 kg, respectively. At 6 months postsurgery, strength measurements of the operated shoulder ranged from 1.4 to 12.0 kg with a CCC of 0.66 (P<.001) and mean strength difference of 0.9 kg (n=68). Respective 6-month measurements of the contralateral side (n=52) ranged from 2.0 to 15.9 kg with a CCC of 0.73 (P<.001) and mean strength difference of 0.03 kg. Absolute and change values in shoulder strength assessments using an unsecured SB and isometric dynamometer are fairly concordant with mean differences of less than 1 kg between methods. With the variability of strength differences among patients, interpretation of these values for individual patients may be challenging. Nonetheless, unsecured SB and dynamometer methods share only slight and clinically unimportant differences that can provide similar group mean values for use in research along with the calculation of the CS.

[Effect of critical shoulder angle on deltoid muscle strength reduction in patients with rotator cuff tears].

To investigate the synergistic interaction between the deltoid muscle and the rotator cuff muscle group in patients with rotator cuff tears (RCT), as well as the impact of the critical shoulder angle (CSA) on deltoid muscle strength. A retrospective analysis was conducted on clinical data from 42 RCT patients who met the selection criteria and were treated between March 2022 and March 2023. There were 13 males and 29 females, with an age range of 42-77 years (mean, 60.5 years). Preoperative visual analogue scale (VAS) score was 6.0±1.6. CSA measurements were obtained from standard anteroposterior X-ray films before operation, and patients were divided into two groups based on CSA measurements: CSA>35° group (group A) and CSA≤35° group (group B). Handheld dynamometry was used to measure the muscle strength of various muscle group in the shoulder (including the supraspinatus, infraspinatus, subscapularis, and anterior, middle, and posterior bundles of the deltoid). The muscle strength of the unaffected side was compared to the affected side, and muscle imbalance indices were calculated. Muscle imbalance indices between male and female patients, dominant and non-dominant sides, and groups A and B were compared. Pearson correlation analysis was used to examine the relationship between muscle imbalance indices and CSA as well as VAS scores. Muscle strength in all muscle groups on the affected side was significantly lower than on the unaffected side ( P<0.05). The muscle imbalance indices for the supraspinatus, subscapularis, infraspinatus, and anterior, middle, and posterior bundles of the deltoid were 14.8%±24.4%, 5.9%±9.7%, 7.2% (0, 9.1%), 17.2% (5.9%, 26.9%), 8.3%±21.3%, and 10.2% (2.8%, 15.4%), respectively. The muscle imbalance indices of the anterior bundle of the deltoid, supraspinatus, and infraspinatus were significantly lower in male patients compared to female patients ( P<0.05); however, there was no significant difference in muscle imbalance indices among other muscle groups between male and female patients or between the dominant and non-dominant sides ( P>0.05). There was a positive correlation between the muscle imbalance indices of infraspinatus and VAS score ( P<0.05), and a positive correlation between CSA and the muscle imbalance indices of middle bundle of deltoid ( P<0.05). There was no correlation between the muscle imbalance indices of other muscle groups and VAS score or CSA ( P>0.05). Preoperative CSA ranged from 17.6° to 39.4°, with a mean of 31.1°. There were 9 cases in group A and 33 cases in group B. The muscle imbalance indices of the anterior bundle of the deltoid was significantly lower in group A compared to group B ( P<0.05), while there was no significant difference in muscle imbalance indices among other muscle groups between group A and group B ( P>0.05). Patients with RCT have a phenomenon of deltoid muscle strength reduction, which is more pronounced in the population with a larger CSA.

Evaluation of Survivorship of Asymptomatic Degenerative Rotator Cuff Tears in Patients 65 Years and Younger: A Prospective Analysis with Long-Term Follow Up.

The purpose of this prospective study is to describe the mid to long-term natural history of untreated asymptomatic degenerative rotator cuff tears in patients 65 years and younger. Subjects with an asymptomatic rotator cuff tear in one shoulder and a contralateral painful cuff tear age 65 years or younger were enrolled in a previously described prospective longitudinal study. Annual physical and ultrasonographic evaluations and surveillance for pain development were performed utilizing independent examiners for the asymptomatic shoulder. Two hundred twenty-nine subjects (mean age 57.1 years) were followed for a median of 7.1 (range 0.3-13.1) years. Tear enlargement occurred in 138 (60%) shoulders. Full-thickness tears were at greater risk for enlargement compared to partial-thickness (HR=2.93, 95%CI 1.71-5.03, p<0.0001) and control shoulders (HR=18.8, 95%CI 4.63-76.1, p<0.0001). Mean survival rates from Kaplan-Meier analyses indicate that full-thickness tears enlarged earlier (mean 4.7, 95%CI 4.1-5.2 years) than partial-thickness (mean 7.4, 95%CI 6.2-8.5 years) and control shoulders (mean 9.7, 95%CI 9.0-10.4 years). Tear presence in the dominant shoulder was associated with a greater enlargement risk (HR=1.70, 95%CI 1.21-1.39, p=0.002). Patient age (p=0.37) and gender (p=0.74) were not associated with tear enlargement. The 2,5 and 8-year survivorship free of tear enlargement for full-thickness tears was 74%, 42% and 20%, respectively. Shoulder pain developed in 131 (57%) shoulders. Pain development was associated with tear enlargement (HR=1.79, 95%CI 1.24-2.58, p=0.002) and was more common in full-thickness tears compared to controls (p=0.0003) and partial tears (p=0.01). An analysis of progression of muscle degeneration was performed 138 shoulders with full-thickness tears. Tear enlargement was seen in 104 of 138 (75%) of these shoulders during follow-up (median 7.7 [6.0] years). Progression of muscle fatty degeneration was seen in the supraspinatus in 46 (33%) and the infraspinatus in 40 (29%) shoulders. Adjusting for age, both the presence of fatty muscle degeneration and the progression of muscle changes for both the supraspinatus (p<0.0001) and infraspinatus (p<0.0001) muscles were associated with tear size. For both the supraspinatus (p=0.03) and infraspinatus (p=0.03) muscles, tear enlargement was significantly associated with progression of muscle fatty degeneration. Anterior cable integrity was significantly associated with the risk of muscle degeneration progression for both the supraspinatus (p<0.0001) and the infraspinatus (p=0.005) muscles. Asymptomatic degenerative rotator cuff tears progress in patient 65 years and younger. Full-thickness rotator cuff tears have a higher risk of continued tear enlargement, progression of fatty muscle degeneration and pain development than partial-thickness tears.

Gene Expression in Synovium of Rotator Cuff Tear Patients Determined by RNA Sequencing.

Rotator cuff tear (RCT) is a common shoulder disorder related to pain and dysfunction. However, the pathological mechanism of RCT remains unclear. Thus, this study aims to investigate the molecular events in RCT synovium and identify possible target genes and pathways as determined by RNA sequencing (RNA-Seq). The synovial tissue was biopsied from 3 patients with RCT (RCT group) and 3 patients with shoulder instability (Control group) during arthroscopic surgery. Then, differentially expressed (DE) mRNAs, long non-coding RNAs (lncRNAs) and micro RNAs (miRNAs) were comprehensively profiled by RNA-Seq. Gene ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and competing endogenous RNA (ceRNA) network analysis were performed to identify the potential functions of these DE genes. 447 mRNAs, 103 lncRNAs and 15 miRNAs were identified differentially expressed. The DE mRNAs were highlighted in inflammatory pathway including up-regulated T cell costimulation, positive regulation of T cell activation, and T cell receptor signaling. Down-regulated fatty acid degradation pathway and 5'-AMP-activated protein kinase (AMPK) signaling in RCT group are also enriched. Validation assay showed that the expression of pro-inflammatory molecules including IL21R, CCR5, TNFSF11, and MMP11 was significantly increased in RCT group compared with Control group. CeRNA analysis further revealed lncRNA-miRNA-mRNA regulatory networks involving IL21R and TNFSF11 in RCT. Activated synovial inflammation is the remarkable event of RCT. Importantly, increased T cell activation and disordered fatty acid metabolism signaling might play a significant role. ceRNA networks involving IL21R and TNFSF11 identified could potentially control the progression of RCT. In conclusion, our findings could provide new evidence for the molecular mechanisms of RCT and might identify new therapeutic targets.