Fibroblast growth factor 8b (FGF-8b) enhances myogenesis and inhibits adipogenesis in rotator cuff muscle cell populations in vitro.

Fatty expansion is one of the features of muscle degeneration due to muscle injuries, and its presence interferes with muscle regeneration. Specifically, poor clinical outcomes have been linked to fatty expansion in rotator cuff tears and repairs. Our group recently found that fibroblast growth factor 8b (FGF-8b) inhibits adipogenic differentiation and promotes myofiber formation of mesenchymal stem cells in vitro. This led us to hypothesize that FGF-8b could similarly control the fate of muscle-specific cell populations derived from rotator cuff muscle involved in muscle repair following rotator cuff injury. In this study, we isolate fibro-adipogenic progenitor cells (FAPs) and satellite stem cells (SCs) from rat rotator cuff muscle tissue and analyzed the effects of FGF-8b supplementation. Utilizing a cell plating protocol, we successfully isolate FAPs-rich fibroblasts (FIBs) and SCs-rich muscle progenitor cells (MPCs). Subsequently, we demonstrate that FIB adipogenic differentiation can be inhibited by FGF-8b, while MPC myogenic differentiation can be enhanced by FGF-8b. We further demonstrate that phosphorylated ERK due to FGF-8b leads to the inhibition of adipogenesis in FIBs and SCs maintenance and myofiber formation in MPCs. Together, these findings demonstrate the powerful potential of FGF-8b for rotator cuff repair by altering the fate of muscle undergoing degeneration.

Fatigue-related changes in intermuscular electromyographic coherence across rotator cuff and deltoid muscles in individuals with and without subacromial pain.

Neuromuscular fatigue induces superior migration of the humeral head in individuals with subacromial pain. This has been attributed to weakness of rotator cuff muscles and overactive deltoid muscles. Investigation of common inputs to motoneuron pools of the rotator cuff and deltoid muscles offers valuable insight into the underlying mechanisms of neuromuscular control deficits associated with subacromial pain. This study aims to investigate intermuscular coherence across the rotator cuff and deltoid muscles during a sustained submaximal isometric fatiguing contraction in individuals with and without subacromial pain. Twenty symptomatic and 18 asymptomatic young adults participated in this study. Surface electromyogram (EMG) was recorded from the middle deltoid (MD) and infraspinatus (IS). Intramuscular EMG was recorded with fine-wire electrodes in the supraspinatus (SS). Participants performed an isometric fatiguing contraction of 30° scaption at 25% maximum voluntary contraction (MVC) until endurance limit. Pooled coherence of muscle pairs (SS-IS, SS-MD, IS-MD) in the 2-5 Hz (delta), 5-15 Hz (alpha), and 15-35 Hz (beta) frequency bands during the initial and final 30 s of the fatigue task were compared. SS-IS and SS-MD delta-band coherence increased with fatigue in the asymptomatic group but not the symptomatic group. In the alpha and beta bands, SS-IS and SS-MD coherence increased with fatigue in both groups. IS-MD beta-band coherence was greater in the symptomatic than the asymptomatic group. Individuals with subacromial pain failed to increase common drive across rotator cuff and deltoid muscles and have altered control strategies during neuromuscular fatigue. This may contribute to glenohumeral joint instability and subacromial pain experienced by these individuals.NEW & NOTEWORTHY Through the computation of shared neural drive across glenohumeral muscles, this study reveals that individuals with subacromial pain were unable to increase shared neural drive within the rotator cuff and across the supraspinatus and deltoid muscles during neuromuscular fatigue induced by sustained isometric contraction. These deficits in common drive across the shoulder muscles likely contribute to the joint instability and pain experienced by these individuals.

Healthy Tendon Stem Cell-Derived Exosomes Promote Tendon-To-Bone Healing of Aged Chronic Rotator Cuff Tears by Breaking the Positive-Feedback Cross-Talk between Senescent Tendon Stem Cells and Macrophages through the Modulation of Macrophage Polarization.

The re-tear rate of rotator cuff tears (RCT) after surgical repair is high, especially in aged patients with chronic tears. Senescent tendon stem cells (s-TSCs) generally exist in aged and chronically torn rotator cuff tendons and are closely associated with impaired tendon-to-bone healing results. The present study found a positive feedback cross-talk between s-TSCs and macrophages. The conditioned medium (CM) from s-STCs can promote macrophage polarization mainly toward the M1 phenotype, whose CM reciprocally accelerated further s-TSC senescence. Additional healthy tendon stem-cells derived exosomes (h-TSC-Exos) can break this positive feedback cross-talk by skewing macrophage polarization from the M1 phenotype to the M2 phenotype, attenuating s-TSCs senescence. S-TSC senescence acceleration or attenuation effects induced by M1 or M2 macrophages are associated with the inhibition or activation of the bone morphogenetic protein 4 signaling pathway following RNA sequencing analysis. Using an aged-chronic rotator cuff tear rat model, it is found that h-TSC-Exos can shift the microenvironment in the tendon-to-bone interface from a pro-inflammatory to an anti-inflammatory type at the acute postoperative stage and improve the tendon-to-bone healing results, which are associated with the rejuvenated s-TSCs. Therefore, this study proposed a potential strategy to improve the healing of aged chronic RCT.

Collagen degradation assessment with an in vitro rotator cuff tendinopathy model using multiparametric ultrashort-TE magnetization transfer (UTE-MT) imaging.

PURPOSE: This study aims to assess ultrashort-TE magnetization transfer (UTE-MT) imaging of collagen degradation using an in vitro model of rotator cuff tendinopathy. METHODS: Thirty-six supraspinatus tendon specimens were divided into three groups and treated with 600 U collagenase (Group 1), 150 U collagenase (Group 2), and phosphate buffer saline (Group 3). UTE-MT imaging was performed to assess changes in macromolecular fraction (MMF), macromolecule transverse relaxation time (T2m), water longitudinal relaxation rate constant (R1m), the magnetization exchange rate from the macromolecular to water pool (Rm0 w) and from water to the macromolecular pool (Rm0 m), and magnetization transfer ratio (MTR) at baseline and following digestion and their differences between groups. Biochemical and histological studies were conducted to determine the extent of collagen degradation. Correlation analyses were performed with MMF, T2m, R1m, Rm0 w, Rm0 m, and MTR, respectively. Univariate and multivariate linear regression analyses were performed to evaluate combinations of UTE-MT parameters to predict collagen degradation. RESULTS: MMF, T2m, R1m, Rm0 m, and MTR decreased after digestion. MMF (r = -0.842, p < 0.001), MTR (r = -0.78, p < 0.001), and Rm0 m (r = -0.662, p < 0.001) were strongly negatively correlated with collagen degradation. The linear regression model of differences in MMF and Rm0 m before and after digestion explained 68.9% of collagen degradation variation in the tendon. The model of postdigestion in MMF and T2m and the model of MTR explained 54.2% and 52.3% of collagen degradation variation, respectively. CONCLUSION: This study highlighted the potential of UTE-MT parameters for evaluation of supraspinatus tendinopathy.

Three-dimensional architecture and moment arms of human rotator cuff muscles in vivo: Interindividual, intermuscular, and intramuscular variations.

The human rotator cuff consists of four muscles, each with a complex, multipennate architecture. Despite the functional and clinical importance, the architecture of the human rotator cuff has yet to be clearly described in humans in vivo. The purpose of this study was to investigate the intramuscular, intermuscular, and interindividual variations in architecture and moment arms of the human rotator cuff. Muscle volumes, fascicle lengths, physiological cross-sectional areas (PCSAs), pennation angles, and moment arms of all four rotator cuff muscles were measured from mDixon and diffusion tensor imaging (DTI) scans of the right shoulders of 20 young adults. In accordance with the most detailed dissections available to date, we found substantial intramuscular variation in fascicle length (coefficients of variation (CVs) ranged from 26% to 40%) and pennation angles (CVs ranged from 56% to 62%) in all rotator cuff muscles. We also found substantial intermuscular and interindividual variations in muscle volumes, but relatively consistent mean fascicle lengths, pennation angles, and moment arms (CVs for all ≤17%). Moreover, when expressed as a proportion of total rotator cuff muscle volume, the volumes of individual rotator cuff muscles were highly consistent between individuals and sexes (CVs ≤16%), suggesting that rotator cuff muscle volumes scale uniformly, at least in a younger population without musculoskeletal problems. Together, these data indicate limited interindividual and intermuscular variability in architecture, which may simplify scaling routines for musculoskeletal models. However, the substantial intramuscular variation in architecture questions the validity of previously reported mean architectural parameters to adequately describe rotator cuff function.

Rotator cuff muscle fibrosis can be assessed using ultrashort echo time magnetization transfer MRI with fat suppression.

Muscle degeneration following rotator cuff tendon tearing is characterized by fatty infiltration and fibrosis. While tools exist for the characterization of fat, the ability to noninvasively assess muscle fibrosis is limited. The purpose of this study was to evaluate the capability of quantitative ultrashort echo time T1 (UTE-T1) and UTE magnetization transfer (UTE-MT) mapping with and without fat suppression (FS) for the differentiation of injured and control rotator cuff muscles and for the detection of fibrosis. A rat model of chronic massive rotator cuff tearing (n = 12) was used with tenotomy of the right supraspinatus and infraspinatus tendons and silicone implants to prevent healing. Imaging was performed on a 3-T scanner, and UTE-T1 mapping with and without FS and UTE-MT with and without FS for macromolecular fraction (MMF) mapping was performed. At 20 weeks postinjury, T1 and MMF were measured in the supraspinatus and infraspinatus muscles of the injured and contralateral, internal control sides. Histology was performed and connective tissue fraction (CTF) was measured, defined as the area of collagen-rich extracellular matrix divided by the total muscle area. Paired t-tests and correlation analyses were performed. Significant differences between injured and control sides were found for CTF in the supraspinatus (mean ± SD, 14.5% ± 3.9% vs. 11.3% ± 3.7%, p = 0.01) and infraspinatus (17.0% ± 5.4% vs. 12.5% ± 4.6%, p < 0.01) muscles, as well as for MMF using UTE-MT FS in the supraspinatus (9.7% ± 0.3% vs. 9.5% ± 0.2%, p = 0.04) and infraspinatus (10.9% ± 0.8% vs. 10.1% ± 0.5%, p < 0.01) muscles. No significant differences between sides were evident for T1 without or with FS or for MMF using UTE-MT. Only MMF using UTE-MT FS was significantly correlated with CTF for both supraspinatus (r = 0.46, p = 0.03) and infraspinatus (r = 0.51, p = 0.01) muscles. Fibrosis occurs in rotator cuff muscle degeneration, and the UTE-MT FS technique may be helpful to evaluate the fibrosis component, independent from the fatty infiltration process.

The Relationship Among Probable SARCopenia, Osteoporosis and SuprasPinatus Tendon Tears in Postmenopausal Women: The SARCOSP Study.

We aimed to investigate the relationship among probable sarcopenia, osteoporosis (OP) and supraspinatus tendon (SSP) tears in postmenopausal women. Postmenopausal women screened/followed for OP were recruited. Demographic data, comorbidities, exercise/smoking status, and handgrip strength values were recorded. Probable sarcopenia was diagnosed as handgrip strength values < 20 kg. Achilles and SSP thicknesses were measured using ultrasound. Among 1443 postmenopausal women, 268 (18.6%) subjects had SSP tears. Unilateral tears were on the dominant side in 146 (10.1%) and on the non-dominant side in 55 women (3.8%). In contrast to those without, women with SSP tears had older age, lower level of education, thinner SSP and lower grip strength (all p < 0.05). In addition, they had higher frequencies of hypertension, hyperlipidemia, DM, OP and probable sarcopenia, but lower exercise frequency (all p < 0.05). Binary logistic regression modeling revealed that age [odds ratio (OR): 1.046 (1.024-1.067 95% CI)], hypertension [OR: 1.560 (1.145-2.124 95% CI)], OP [OR: 1.371 (1.022-1.839 95% CI)] and probable sarcopenia [OR: 1.386 (1.031-1.861 95% CI)] were significant predictors for SSP tears (all p < 0.05). This study showed that age, presence of hypertension, probable sarcopenia and OP were related with SSP tears in postmenopausal women. To this end, although OP appeared to be related to SSP tears, SSP tear/thickness evaluation can be recommended for OP patients, especially those who have other risk factors such as older age, higher BMI, hypertension, and probable sarcopenia.

Characterizing the Myoarchitecture of the Supraspinatus and Infraspinatus Muscles With MRI Using Diffusion Tensor Imaging.

BACKGROUND: The societal cost of shoulder disabilities in our aging society keeps rising. Providing biomarkers of early changes in the microstructure of rotator cuff (RC) muscles might improve surgical planning. Elevation angle (E1A) and pennation angle (PA) assessed by ultrasound change with RC tears. Furthermore, ultrasounds lack repeatability. PURPOSE: To propose a repeatable framework to quantify the myocyte angulation in RC muscles. STUDY TYPE: Prospective. SUBJECTS: Six asymptomatic healthy volunteers (1 female aged 30 years; 5 males, mean age 35 years, range 25-49 years), who underwent three repositioned scanning sessions (10 minutes apart) of the right infraspinatus muscle (ISPM) and supraspinatus muscle (SSPM). FIELD STRENGTH/SEQUENCE: 3-T, T1-weighted and diffusion tensor imaging (DTI; 12 gradient encoding directions, b-values of 500 and 800 s/mm2 ). ASSESSMENT: Each voxel was binned in percentage of depth defined by the shortest distance in the antero-posterior direction (manual delineation), i.e. the radial axis. A second order polynomial fit for PA across the muscle depth was used, while E1A described a sigmoid across depth: E 1 A sig = E 1 A range × sigmf 1 : 100 % depth , - EA 1 grad   ,   E 1 A asym + E 1 A shift . STATISTICAL TESTS: Repeatability was assessed with the nonparametric Wilcoxon's rank-sum test for paired comparisons across repeated scans in each volunteer for each anatomical muscle region and across repeated measures of the radial axis. A P-value <0.05 was considered statistically significant. RESULTS: In the ISPM, E1A was constantly negative, became helicoidal, then mainly positive across the antero-posterior depth, respective at the caudal, central and cranial regions. In the SSPM, posterior myocytes ran more parallel to the intramuscular tendon ( PA ≈ 0 ° ), while anterior myocytes inserted with a pennation angle ( PA ≈ - 20 ° ). E1A and PA were repeatable in each volunteer (error < 10%). Intra-repeatability of the radial axis was achieved (error < 5%). DATA CONCLUSION: ElA and PA in the proposed framework of the ISPM and SSPM are repeatable with DTI. Variations of myocyte angulation in the ISPM and SSPM can be quantified across volunteers. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.

Biceps Pulley Lesions: Diagnostic Accuracy of Nonarthrographic Shoulder MRI and the Value of Various Diagnostic Signs.

BACKGROUND: There is limited data in the literature regarding the role of nonarthrographic MRI for detecting biceps pulley (BP) lesions. PURPOSE: To assess the accuracy of nonarthrographic MRI for detecting BP lesions, and to evaluate the diagnostic value of various MRI signs (superior glenohumeral ligament discontinuity/nonvisibility, long head of biceps (LHB) displacement sign or subluxation/dislocation, LHB tendinopathy, and supraspinatus and subscapularis tendon lesions) in detecting such lesions. STUDY TYPE: Retrospective. POPULATION: 84 patients (32 in BP-lesion group and 52 in BP-intact group-as confirmed by arthroscopy). FIELD STRENGTH/SEQUENCE: 1.5-T, T1-weighted turbo spin echo (TSE), T2-weighted TSE, and proton density-weighted TSE spectral attenuated inversion recovery (SPAIR) sequences. ASSESSMENT: Three radiologists independently reviewed all MRI data for the presence of BP lesions and various MRI signs. The MRI signs and final MRI diagnoses were tested for accuracy regarding detecting BP lesions using arthroscopy results as the reference standard. Furthermore, the inter-reader agreement (IRA) between radiologists was determined. STATISTICAL TESTS: Student's t-tests, Chi-squared, and Fisher's exact tests, and 4-fold table test were used. The IRA was calculated using Kappa statistics. A P-value <0.05 was considered statistically significant. RESULTS: The sensitivity, specificity, and accuracy of nonarthrographic MRI for detecting BP lesions were 65.6%-78.1%, 90.4%-92.3%, and 81%-86.9%, respectively. The highest accuracy was noticed for the LHB displacement sign (84.5%-86.9%), and the highest sensitivity was registered for the LHB tendinopathy sign (87.5%). Furthermore, the highest specificity was observed for the LHB displacement sign and LHB subluxation/dislocation sign (98.1%-100%). The IRA regarding final MRI diagnosis and MRI signs of BP lesions was good to very good (κ = 0.76-0.98). DATA CONCLUSION: Nonarthrographic shoulder MRI may show good diagnostic accuracy for detecting BP lesions. The LHB displacement sign could serve as the most accurate and specific sign for diagnosis of BP lesions. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Acidosis induces significant changes to the murine supraspinatus enthesis organic matrix.

Rotator cuff pathology is a common musculoskeletal condition that disproportionately affects older adults, as well as patients with diabetes mellitus and chronic kidney disease. It is known that increased age and kidney dysfunction have been correlated to acidotic states, which may be related to the increased incidence of rotator cuff injury. In order to investigate the potential relationship between acidosis and rotator cuff composition and mechanics, this study utilizes a 14-day murine model of metabolic acidosis and examines the effects on the supraspinatus tendon-humeral head attachment complex. The elastic matrix in the enthesis exhibited significant changes beginning at day 3 of acidosis exposure. At day 3 and day 7 timepoints, there was a decrease in collagen content seen in both mineralized and unmineralized tissue as well as a decrease in mineral:matrix ratio. There is also evidence of both mineral dissolution and reprecipitation as buffering ions continually promote pH homeostasis. Mechanical properties of the tendon-to-bone attachment were studied; however, no significant changes were elicited in this 14-day model of acidosis. These findings suggest that acidosis can result in significant changes in enthesis composition over the course of 14 days; however, enthesis mechanics may be more structurally mediated rather than affected by compositional changes.

Fully automatic algorithm for detecting and tracking anatomical shoulder landmarks on fluoroscopy images with artificial intelligence.

OBJECTIVE: Patients with rotator cuff tears present often with glenohumeral joint instability. Assessing anatomic angles and shoulder kinematics from fluoroscopy requires labelling of specific landmarks in each image. This study aimed to develop an artificial intelligence model for automatic landmark detection from fluoroscopic images for motion tracking of the scapula and humeral head. MATERIALS AND METHODS: Fluoroscopic images were acquired for both shoulders of 25 participants (N = 12 patients with unilateral rotator cuff tear, 6 men, mean (standard deviation) age: 63.7 ± 9.7 years; 13 asymptomatic subjects, 7 men, 58.2 ± 8.9 years) during a 30° arm abduction and adduction movement in the scapular plane with and without handheld weights of 2 and 4 kg. A 3D full-resolution convolutional neural network (nnU-Net) was trained to automatically locate five landmarks (glenohumeral joint centre, humeral shaft, inferior and superior edges of the glenoid and most lateral point of the acromion) and a calibration sphere. RESULTS: The nnU-Net was trained with ground-truth data from 6021 fluoroscopic images of 40 shoulders and tested with 1925 fluoroscopic images of 10 shoulders. The automatic landmark detection algorithm achieved an accuracy above inter-rater variability and slightly below intra-rater variability. All landmarks and the calibration sphere were located within 1.5 mm, except the humeral landmark within 9.6 mm, but differences in abduction angles were within 1°. CONCLUSION: The proposed algorithm detects the desired landmarks on fluoroscopic images with sufficient accuracy and can therefore be applied to automatically assess shoulder motion, scapular rotation or glenohumeral translation in the scapular plane. CLINICAL RELEVANCE STATEMENT: This nnU-net algorithm facilitates efficient and objective identification and tracking of anatomical landmarks on fluoroscopic images necessary for measuring clinically relevant anatomical configuration (e.g. critical shoulder angle) and enables investigation of dynamic glenohumeral joint stability in pathological shoulders. KEY POINTS: • Anatomical configuration and glenohumeral joint stability are often a concern after rotator cuff tears. • Artificial intelligence applied to fluoroscopic images helps to identify and track anatomical landmarks during dynamic movements. • The developed automatic landmark detection algorithm optimised the labelling procedures and is suitable for clinical application.

A prospective study of 100 patients with rotator cuff tendinopathy showed no correlation between subacromial bursitis and the efficacy of ultrasound-guided corticosteroid injection.

OBJECTIVES: The objective of this study was to determine whether the presence of subacromial bursitis in patients with rotator cuff tendinopathy (RCT) was associated with a better outcome after ultrasound (US)-guided subacromial corticosteroid injection. METHODS: A single-center prospective study was performed including patients referred for subacromial injection to manage RCT. At baseline, all patients received an US-guided intra-bursal injection of betamethasone (1 ml). The primary endpoint was reduced pain 3 months (M3) after the procedure: a good responder was defined by a decrease in Visual Analogue Scale pain of more than 30%. Secondary endpoints included functional recovery assessed by the Oxford Shoulder Score (OSS) and clinical success at 6 weeks (W6). We also explored the association between good clinical response and other factors, such as US or X-ray features. RESULTS: One hundred patients were included and 49 presented with subacromial bursitis. At M3, 60% of patients (54/100) were considered good responders. The rate of good responders did not differ between the bursitis and non-bursitis groups (p = 0.6). During follow-up, OSS improved over time whether bursitis was present or not. We did not find any US or X-ray features significantly associated with a favorable clinical outcome. CONCLUSION: The presence of subacromial bursitis did not influence clinical outcomes at 3 months post-subacromial injection in patients suffering from RCT. CLINICAL RELEVANCE STATEMENT: The presence of subacromial bursitis did not influence clinical outcomes at 3 months post-subacromial corticosteroid injection in patients with rotator cuff tendinopathy. For patient management, looking for ultrasonographic signs of bursitis does not appear relevant for the indication of the injection. KEY POINTS: • Ultrasound-guided subacromial corticosteroid injections led to a significant improvement in 60% of patients suffering from rotator cuff tendinopathy. • The presence of subacromial bursitis was not associated with better improvement at 3 months post-injection. • Except for the Minnesota score referring to job satisfaction, we did not find any baseline clinical, X-ray, or ultrasound characteristics associated with a successful outcome.

The validity of ultrasound and shear wave elastography to assess the quality of the rotator cuff.

OBJECTIVES: US with shear wave elastography (SWE) could reduce the burden and costs of the diagnostic process for patients with rotator cuff disorders. The aim of this study is to investigate the validity of US and SWE in preoperative assessment of fatty infiltration (FI) and muscle atrophy of the supraspinatus (SSP) and infraspinatus (ISP) muscles. METHODS: Patients with a rotator cuff disorder and a recent shoulder CT or MRI scan were eligible to participate. Goutallier and Warner stages of the SSP and ISP muscle were measured on the scan, for assessment of FI and muscle atrophy, respectively. These findings were compared with shear wave velocities (SWVs) assessed on US. Visual assessment of FI on US was compared with the Goutallier stage. To quantify the amount of muscle atrophy, the occupation ratio between SSP fossa and muscle was measured on MRI and US. RESULTS: Seventy-eight shoulders were included in the analysis. The correlation found between the occupation ratio on US and Warner and Goutallier stage and ratio on MRI ranged between r = - 0.550 to 0.589. The Goutallier stage of ISP and SSP muscle assessed on US showed a fair correlation with the Goutallier stage on a scan of r = 0.574 and r = 0.582, respectively. There was a poor correlation between the SWVs and scan results (r = - 0.116 to 0.07). CONCLUSION: SWE is not a valid method to measure the amount of FI or muscle atrophy in the SSP muscle. Therefore, SWE is not a suitable alternative for MRI in standard preoperative diagnostics in rotator cuff pathologies. CLINICAL RELEVANCE STATEMENT: Shear wave elastography should not be used in the diagnostics of rotator cuff pathologies. KEY POINTS: • There is a fair correlation between the Goutallier stage of the supraspinatus and infraspinatus muscle assessed on MRI and CT and visual assessment of fatty infiltration achieved on US. • Shear wave elastography is not a valid tool for the determination of the amount of fatty infiltration or muscle atrophy. • Shear wave elastography should not be used as a cheaper and less burdensome alternative for diagnostics in rotator cuff pathologies.

Development of a new radiographic score for the follow-up of calcific tendinopathy of the rotator cuff.

OBJECTIVES: The aim of this study was to evaluate the psychometric properties of a new x-ray scoring system for calcific tendinopathy of the rotator cuff (CTRC). METHODS: This is a post-hoc analysis of the CALCECHO trial. All patients received an ultrasound-guided puncture and lavage of their calcification. Clinical data and x-rays from baseline and follow-up visits at 7 days (D7), 3 months (M3) and 12 months (M12) were used. The scoring system was based on the reduction in size and density of the calcification compared to the initial x-ray (0 = no change; 1 = decrease of less than 50%; 2 = decrease of between 50 and 90%; 3 = decrease of more than 90%; 4 = complete disappearance). Inter-observer and intra-observer reliability were established between 3 independent investigators (2 experts and one junior) using weighted Kappa calculation. Construct validity was assessed as well as predictive validity and sensitivity to change. RESULTS: Between the two experts, inter-reader reliability was at 0.677, 0.744 and 0.656 at D7, M3 and M12 respectively. Intra-reader reliability was between 0.577 and 0.836 for the two expert readers and between 0.519 and 0.697 for the junior reader. Our score was correlated with shoulder pain and function at M3 and M12 and the score at M3 was predictive of the clinical outcome at M12. Finally, sensitivity to change was 0.8. CONCLUSIONS: Our new score presented good psychometric properties and was correlated with clinical data. It could be useful in the follow-up of patients treated for CTRC.

Shoulder terminal sensory articular nerve radiofrequency ablation for nonsurgical refractory shoulder pain due to rotator cuff pathology and osteoarthritis: a technical note.

BACKGROUND: Given the high prevalence of chronic shoulder pain and encouraging early results of terminal sensory articular branch radiofrequency ablation to treat shoulder pain, research is warranted to refine the procedural technique on the basis of updated neuroanatomic knowledge with the goal of further improving patient outcomes. OBJECTIVE: We describe an updated radiofrequency ablation protocol that accounts for varied locations of the terminal sensory articular branches of the suprascapular, axillary, subscapular, and lateral pectoral nerves within individual patients. DESIGN: Technical note. METHODS: Cadaveric studies delineating the sensory innervation of the shoulder joint were reviewed, and a more comprehensive radiofrequency ablation protocol is proposed relative to historical descriptions. CONCLUSIONS: The proposed radiofrequency ablation protocol, which is based on neuroanatomic dissections of the shoulder joint, will provide a safe means of more complete sensory denervation and potentially improve clinical outcomes compared with historical descriptions, the efficacy of the new protocol must be confirmed in prospective studies.

Enhanced Outcomes and Safety of Reverse Shoulder Arthroplasty in Rotator Cuff Deficiency and Proximal Humerus Fractures: A 22-Patient Retrospective Analysis.

BACKGROUND Reverse shoulder arthroplasty (RSA) is an accepted treatment that provides reproducible results in the treatment of rotator cuff deficiency and proximal humerus fractures. This single-center study aimed to evaluate the outcomes from reverse shoulder arthroplasty for rotator cuff insufficiency and proximal humerus fractures in 22 patients from a single center. MATERIAL AND METHODS Twenty-two patients were included in the study. The median age of the patients was 66 years (Range: 58-95). Proximal humerus fractures were diagnosed using X-ray and CT, while rotator cuff tears were diagnosed using MRI. For the assessment of joint function, the Constant-Murley score, the American Shoulder and Elbow Surgeons (ASES), and the Disabilities of Arm, Shoulder, and Hand (DASH) scores were used as patient-reported outcome measures. Kaplan-Meier analysis was conducted to evaluate implant survival. RESULTS The mean follow-up duration was 4.05±1.2 years. Significant improvements were observed: ASES Score: Increased from 35.8±2.8 to 81.3±5.4 (p<0.001). VAS Pain Score: Decreased from 7.3±1 to 2.9±0.9 (p<0.001). DASH Score: Improved from 66.3±4.3 to 32.5±3.6 (p<0.001). Constant-Murley Score: Increased from 48.3±3.5 to 74.6±7.7 (p<0.001). Kaplan-Meier analysis estimated implant survival at 6.7 years (95% CI, 6.3-7.2). CONCLUSIONS When performed with appropriate indications, RSA yields positive results, as seen in the literature and our study. Interscalene block anesthesia, advancements in implant technology, and adherence to surgical procedures can reduce RSA complications and ensure its safe application.

Reproducibility of Exercise Interventions in Randomized Controlled Trials for the Treatment of Rotator Cuff-Related Shoulder Pain: A Systematic Review.

OBJECTIVE: To determine the reproducibility of exercise therapy interventions in randomized controlled trials for rotator cuff-related shoulder pain (RCRSP). DATA SOURCES: Data sources included Medline, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, and SPORTDiscus from studies published from database inception to April 23, 2022. STUDY SELECTION: Randomized controlled trials studying the use of exercise therapy for RCRSP. DATA EXTRACTION: Two reviewers extracted exercise reporting details from all studies using the Template for Intervention Description and Replication (TIDieR) and the modified Consensus on Exercise Reporting Template (CERT). The same 2 reviewers assessed risk of bias of all studies using Cochrane Risk of Bias Tool version 2.0. DATA SYNTHESIS: For 104 studies meeting inclusion criteria, the average number of items reported on the TIDieR was 5.27 (SD 2.50, range 1-12 out of 12) and 5.09 (SD 4.01, range 0-16 out of 16) on the CERT. Improved reporting over time was seen on both the TIDieR and CERT dating back to 1993 and through April 23, 2022. When comparing groups of studies published before and after the TIDieR (2014) and CERT (2016) were established, a statistically significant increase in median scores was noted on the TIDieR (P=.02) but not the CERT (P=.31). Quality of exercise therapy reporting was highest in studies with "low risk" of bias, and lowest in studies with "high risk" of bias on the RoB-2. CONCLUSION: Overall exercise reporting in trials for RCRSP is incomplete despite the development of the TIDieR and CERT checklists. This has implications for translating evidence into practice.

Effects of propofol versus sevoflurane on surgical field visibility during arthroscopic rotator cuff repair: a randomized trial.

BACKGROUND: During arthroscopic rotator cuff repair (ARCR), clear surgical field visibility (SFV) is the basis of successful surgery, but the choice of anesthesia maintenance drugs may have different effects on SFV. In this study, we aimed to compare the effects of propofol- and sevoflurane-based general anesthesia on SFV in patients undergoing ARCR. METHODS: Patients (n = 130) undergoing elective ARCR in the lateral decubitus position were randomized into either the propofol group or sevoflurane group (65 per group). The duration of surgery and increased pressure irrigation (IPI), Boezaart score, rocuronium consumption and usage of remifentanil were recorded. The time of both spontaneous respiration recovery and extubation and the incidences of postoperative nausea and vomiting and agitation were also recorded. RESULTS: The Boezaart score, duration of IPI and ratio of the duration of IPI to the duration of surgery (IPI/S ratio) were similar between the groups (P > 0.05). Rocuronium consumption, number of patients requiring remifentanil infusion and total remifentanil consumption were significantly lower in the sevoflurane group (P < 0.05). The spontaneous respiration recovery time was significantly longer in the propofol group (P < 0.05), but there were no differences in the extubation time between the groups(P > 0.05). CONCLUSIONS: Compared with propofol, sevoflurane provides equally clear SFV while improving the convenience of anesthesia maintenance in ARCR patients with interscalene plexus (ISB) combined with general anesthesia. TRIAL REGISTRATION: This single-center, prospective, RCT was retrospective registered at Chinese Clinical Trial Registry with the registration number ChiCTR2300072110 (02/06/2023).

Development of a deep learning-based fully automated segmentation of rotator cuff muscles from clinical MR scans.

BACKGROUND: The fatty infiltration and atrophy in the muscle after a rotator cuff (RC) tear are important in surgical decision-making and are linked to poor clinical outcomes after rotator cuff repair. An accurate and reliable quantitative method should be developed to assess the entire RC muscles. PURPOSE: To develop a fully automated approach based on a deep neural network to segment RC muscles from clinical magnetic resonance imaging (MRI) scans. MATERIAL AND METHODS: In total, 94 shoulder MRI scans (mean age = 62.3 years) were utilized for the training and internal validation datasets, while an additional 20 MRI scans (mean age = 62.6 years) were collected from another institution for external validation. An orthopedic surgeon and a radiologist manually segmented muscles and bones as reference masks. Segmentation performance was evaluated using the Dice score, sensitivities, precision, and percent difference in muscle volume (%). In addition, the segmentation performance was assessed based on sex, age, and the presence of a RC tendon tear. RESULTS: The average Dice score, sensitivities, precision, and percentage difference in muscle volume of the developed algorithm were 0.920, 0.933, 0.912, and 4.58%, respectively, in external validation. There was no difference in the prediction of shoulder muscles, with the exception of teres minor, where significant prediction errors were observed (0.831, 0.854, 0.835, and 10.88%, respectively). The segmentation performance of the algorithm was generally unaffected by age, sex, and the presence of RC tears. CONCLUSION: We developed a fully automated deep neural network for RC muscle and bone segmentation with excellent performance from clinical MRI scans.

More severe supraspinatus tendon degeneration on the contralateral shoulders in patients treated for symptomatic rotator cuff tears compared to healthy controls: a quantitative MRI-based study.

BACKGROUND: Patients treated for symptomatic rotator cuff tear (RCT) on one shoulder seem to have a higher prevalence of RCT on the contralateral shoulder. PURPOSE: To compare the supraspinatus (SSP) tendon and RC muscle properties on the contralateral shoulder in patients after repair surgery to those healthy individuals using quantitative magnetic resonance imaging (MRI). MATERIAL AND METHODS: A total of 23 patients treated for RCT (group A) and 23 healthy controls (group B) were recruited. Constant score, visual analog scale score (VAS), and MRI examinations were conducted. The SSP tendon structural status was graded based on the Zlatkin classification and quantified on ultrashort echo time (UTE)-T2* mapping images. Fatty degeneration of RC muscles was classified according to the Goutallier classification and quantified on T2 mapping. RESULTS: The Constant and VAS scores were comparable between groups A and B (all P >0.05). No significant differences were observed in tendon structural status between the two groups (P >0.05). However, significant differences were established in UTE-T2* values of the SSP tendon on the distal subregion between groups A and B (16.4 ± 2.4 ms vs. 14.8 ± 1.2 ms; P = 0.01). Regarding muscle degeneration, no significant differences were displayed in T2 values and Goutallier classification of RC muscles (all P >0.05). CONCLUSION: Patients with a treated RCT demonstrated inferior SSP tendon in the distal subregion on the contralateral shoulders one year postoperatively compared to that of healthy controls based on quantitative MRI data.