Full-thickness Rotator Cuff Research Articles

Histological and biochemical changes in a rat rotator cuff tear model with or without the subacromial bursa

The subacromial bursa (SAB) plays an important role in the tendon healing process. Based on previous reports, co-culture of the rotator cuff (RC) and SAB have been shown to increase the tendon-related gene expressions, inflammatory cytokines, and tensile strength. However, the nature of the specific biochemical alterations during the inflammatory and repair phases of tendon healing with or without the SAB remain unknown. Using a full-thickness RC tear rat model, we determined how the presence or absence of the SAB alters the histological characteristics and gene expressions. After 3 and 6 weeks, tissues were collected for histological and real-time quantitative polymerase chain reaction (RT-qPCR) evaluations. Results showed greater cell density at 3 weeks, neovascularization and tendon thickening at 6 weeks with SAB preservation. Immunostaining revealed significant increases in type 3 collagen (COL3) expression at 6 weeks with SAB preservation. The RT-qPCR results showed that SAB preservation induced significant increases in the expression of scleraxis, matrix metalloproteinase-13 (MMP-13), interleukin-1β (IL-1β), and inducible nitric oxide synthase (iNOS) at 3 weeks and significant increases in COL3, IL-10, and arginase-1 (Arg-1) at 6 weeks. An RC tear undergoes more appropriate inflammatory and repair phases during the tendon healing process when the SAB is retained.

Obesity and the correlation with full-thickness rotator cuff tears in younger patients

Background The purpose of this study is to assess the relationship between obesity and full-thickness rotator cuff (FT-RTC) tears in patients under 50 years of age. Methods A retrospective review of 571 patients aged 18–70 years who underwent FT-RTC repair was conducted. Patients were stratified into less than 50 years old (LT50; n = 84) and greater than or equal to 50 years old (GT50; n = 487) cohorts. Dependent variables included body mass index (BMI ≥ 30, ≥35, and ≥40), comorbidities, sex, race, and social history. Inter-cohort differences were analyzed with Student's t-tests, Pearson Chi-squared tests, and linear regressions. Results The LT50 cohort reported greater mean BMI (37.61 ± 5.62 vs 35.16 ± 4.62; p = 0.002). There was no difference in %BMI ≥30 between cohorts. The LT50 showed a significantly higher %BMI than the GT50 cohort when stratifying by BMI ≥ 35 [34.5% (35.10–51.30) vs 17.5% (35.00–55.30), p < 0.001] and BMI ≥40 [15.5% (40.10–51.30) vs 6.4% (40.19–55.30), p = 0.004], a 2.5- and 2.7-times greater odds, respectively. Linear regressions of the GT50 cohort demonstrated increasing age was associated with decreased odds of obesity ( β = -0.041, p = 0.003, OR: 0.96, 95% CI: 0.93–0.99). Discussion Although the incidence of FT-RTCs is lower in patients under 50 years of age, the results of this study are the first to suggest that obesity is positively correlated with premature FT-RTCs. Level of Evidence III.

Fat Fractions of the Rotator Cuff Muscles Acquired With 2-Point Dixon MRI: Predicting Outcome After Arthroscopic Rotator Cuff Repair.

The aim of this study was to quantify and compare fat fraction (FF) and muscle volume between patients with failed and intact rotator cuff (RC) repair as well as a control group with nonsurgical conservative treatment to define FF cutoff values for predicting the outcome of RC repair. Patients with full-thickness RC tears who received magnetic resonance imaging (MRI) before and after RC repair including a 2-point Dixon sequence were retrospectively screened. Patients with retear of 1 or more tendons diagnosed on MRI (Sugaya IV-V) were enrolled and matched to patients with intact RC repair (Sugaya I-II) and to a third group with conservatively treated RC tears. Two radiologists evaluated morphological features (Cofield, Patte, and Goutallier), as well as the integrity of the RC after repair (Sugaya). Fat fractions were calculated from the 2-point Dixon sequence, and the RC muscles were segmented semiautomatically to calculate FFs and volume for each muscle. Receiver operator characteristics curves were used to determine FF cutoff values that best predict RC retears. In total, 136 patients were enrolled, consisting of 3 groups: 41 patients had a failed RC repair (58 ± 7 years, 16 women), 50 patients matched into the intact RC repair group, and 45 patients were matched into the conservative treatment group. Receiver operator characteristics curves showed reliable preoperative FF cutoff values for predicting retears at 6.0% for the supraspinatus muscle (0.83 area under the curve [AUC]), 7.4% for the infraspinatus muscle (AUC 0.82), and 8.3% for the subscapularis muscle (0.94 AUC). Preoperative quantitative FF calculated from 2-point Dixon MRI can be used to predict the risk of retear after arthroscopic RC repair with cutoff values between 6% and 8.3%.

Outcome of intraoperative injection of collagen in arthroscopic repair of full-thickness rotator cuff tear: a retrospective cohort study

Rotator cuff (RC) pathologies are considered the most common cause of shoulder disability and pain. Arthroscopic repair of RC tears has proven to be an effective operation. Nonhealing and retear remain significant clinical problems and a challenge to surgeons. In addition, the essential biological augment to enhance RC tendon-bone healing is still under research. The purpose of the study was to assess the safety and efficacy of injection of atelocollagen and acellular dermal matrix (ADM) allograft in arthroscopic repair of full-thickness RC tears. From January 2018 to March 2020, a total of 129 patients with full-thickness RC tear were treated by arthroscopic repair only (group 1, n=36, with a mean age=63.2 years), arthroscopic repair together with atelocollagen 1-mL injection (group 2, n=44, with a mean age=63 years), or RC tears together with ADM allograft 1-mL injection (group 3, n=49, with a mean age=64.6 years). They were prospectively studied. This study included patients with a repairable full-thickness tear of the supraspinatus tendon size <5 cm. We excluded patients with isolated tears of the subscapularis tendon, those with a previous shoulder surgery, and those who had any type of injection for less than 6 weeks. American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form score, Constant Shoulder score, visual analog scale pain score, and range of motion were evaluated preoperatively, at 3, 6, and 12 months of the postoperative period and the final follow-up. In addition, magnetic resonance imaging was performed at 2 months and 12 months postoperatively. The mean follow-up period was 20 months. All groups showed improvement in functional and pain score at the final follow-up; however, there is no superior outcome among the 3 groups (P>.05). After 2 months, the nonhealing rate was 11% (4 of 36) for group 1, 4% (2 of 44) for group 2, and 2% (1 of 49) for group 3 (P>.05). The retear rates after 12 months was 19.4% (7 of 36) for group 1, 13.6% (6 of 44) for group 2, and 20.4% (10 of 49) for group 3 (P>.05). Adverse events were not detected in any groups. Our study did not show superior clinical or radiologic outcomes of atelocollagen and ADM allograft injections in arthroscopic RC repair over 12 months of follow-up in comparison to the control group. However, adverse events related to atelocollagen and ADM allograft injection were not observed.

The Modified Assessment Tool Based on Scapular Y-View for Global Fatty Infiltration in the Supraspinatus Muscle: Correlation, Predictive Performance, and Reliability Analyses

Background: The accurate evaluation of rotator cuff (RC) fatty degeneration after tears is critical for appropriate surgical decision making and prognosis. However, there is currently no reliable and practical tool to reflect the global fatty infiltration (Global-FI) throughout the 3-dimensional (3D) volumetric RC muscles. Purpose: (1) To determine the correlations between 2 modified assessment tools and the Global-FI and their predictive performances and reliabilities for Global-FI prediction, and (2) to compare these predictive parameters with those of the conventional tool using a single scapular Y-view slice. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A total of 49 patients with full-thickness RC tears scheduled to undergo arthroscopic repairs were included, and their surgical shoulders underwent 6-point Dixon magnetic resonance imaging preoperatively. The Global-FI was measured by calculating the 3D-volumetric fat fraction (FF) of the whole supraspinatus muscle through all acquired oblique sagittal slices. As a commonly used radiological landmark, the scapular Y-view was used to evaluate single-plane fatty infiltration (Y-FI) by calculating the FF in 1 slice, defined as the conventional assessment tool. Two modified assessment tools expand the analytic imaging by integrating the FFs from the scapular Y-view slice and its neighboring slices, which were calculated by averaging the FFs of these 3 slices (meanY3-FI) and accumulating local 3D-volumetric FFs from 3 slices (volY3-FI), respectively. The correlations between 3 assessment tools and the Global-FI were analyzed, and the predictive performance for Global-FI prediction using these tools was determined by goodness of fit and agreement. Moreover, the inter- and intraobserver reliabilities of these assessment tools were evaluated. Similar analyses were performed in the small-medium, large, or massive tear subgroups. Results: The Y-FI was significantly higher than the Global-FI in all cases and tear size subgroups, while the 2 modified assessment tools (meanY3-FI and volY3-FI) did not significantly differ from the Global-FI. All assessment tools were significantly correlated with the Global-FI, but the meanY3-FI and volY3-FI showed stronger correlations than the Y-FI, which was also determined in different tear sizes. Moreover, the regression models of the meanY3-FI and volY3-FI showed superior goodness of fit to Y-FI in Global-FI prediction in all cases and subgroups, with larger coefficients of determination (R2) and smaller root mean square errors. The predicted Global-FI using the regression model of volY3-FI had the best agreement with the measured Global-FI, followed by the meanY3-FI, both showing smaller biases and standard deviation of the percentage difference between predicted- and measured Global-FI than the conventional Y-FI. In addition, the 2 modified assessment tools achieved better interobserver and intraobserver reliabilities than the conventional tool in all cases and subgroups. Conclusion: Two modified assessment tools (meanY3-FI and volY3-FI) were comparable with the Global-FI of the whole supraspinatus muscle, showing stronger correlations with the Global-FI and better predictive performances and reliabilities than the conventional tool (Y-FI). Moreover, the volY3-FI was slightly superior to meanY3-FI in the predictive performance and reliability.

Knowledge and appropriateness of care of family physicians and physiotherapists in the management of shoulder pain: a survey study in the province of Quebec, Canada

BackgroundShoulder pain is difficult to diagnose and treat with half of those affected still symptomatic six months after initial consultation. This may be explained by primary care management not conforming to evidence-based practice. This survey evaluated physiotherapists (PTs) and family physicians' (FPs) knowledge and appropriateness of care in shoulder pain management.MethodsA survey sent to PTs and FPs in the province of Quebec, Canada presented four clinical vignettes with cases of rotator cuff (RC) tendinopathy, acute full-thickness RC tear, adhesive capsulitis and traumatic anterior glenohumeral instability. Respondents indicated diagnosis, indications for imaging, specialists’ referrals, and choice of treatments. Answers were compared to recommendations from clinical practice guidelines (CPGs). Participants’ responses were compared between types of providers with Fisher’s exact test.ResultsRespondents (PTs = 175, FPs = 76) were mostly women with less than ten years of experience. More than 80% of PTs and 84% of FPs correctly diagnosed cases presented. Despite this practice not being recommended, more FPs than PTs recommended an imaging test in the initial management of RC tendinopathy (30% compared to 13%, p = 0.001) and adhesive capsulitis (51% compared to 22%, p = 0.02). For full-thickness RC tear and shoulder instability, up to 72% of FPs and 67% of PTs did not refer to a specialist for a surgical opinion, although recommended by CPGs. For RC tendinopathy, 26% of FPs and 2% of PTs (p < 0.001) would have prescribed a corticosteroid infiltration, which is not recommended in the initial management of this disorder. For adhesive capsulitis, significantly more FPs (76%) than PTs (62%) (p < 0.001) suggested an intra-articular corticosteroid infiltration, as recommended by CPGs. For all presented vignettes, up to 95% of family physicians adequately indicated they would refer patients for physiotherapy. In prioritizing rehabilitation interventions, up to 42% of PTs did not consider active exercises as a priority and up to 65% selected passive modalities that are not recommended for all shoulder pain vignettes.ConclusionsMost FPs and PTs were able to make adequate diagnoses and select appropriate treatments for shoulder pain, but practices opposed to evidence-based recommendations were chosen by several respondents. Further training of FPs and PTs may be needed to optimize primary care management of different shoulder disorders.

Supraspinatus fatty infiltration on MRI among older adults receiving physical therapy as initial management for clinically suspected rotator cuff tear: A pilot study.

Rotator cuff (RC) tear is common among adults ≥60 years, with supraspinatus tear most common. Intramuscular fatty infiltration (FI) on imaging is predictive of long-term outcomes following RC tear. Physical therapists routinely diagnose RC tear only by clinical examination since most do not order imaging studies. Thus, there is limited knowledge about FI in older populations receiving physical therapy (PT) for initial management of RC tear. The primary objective of our pilot study is to determine longitudinal differences in supraspinatus FI over time among older adults receiving PT (PT cohort) for initial management of RC tear relative to older adult volunteers (control cohort), and with secondary objective to evaluate longitudinal self-reported shoulder function over time. This was a prospective longitudinal cohort study. Forty adults, 60-85 years, were enrolled at baseline; one follow-up visit at ≥6 months. Shoulder magnetic resonance imaging and clinical screening for Charlson comorbidity index (CCI), body mass index (BMI), and American Shoulder and Elbow Surgeon (ASES) score were completed at baseline and follow-up visits. Supraspinatus FI was evaluated by 6-point Dixon fat fraction and Goutallier grade. PT (n = 15) and control (n = 25) cohorts were stratified by supraspinatus status: Intact (no tear), partial-thickness tear (PTT), and full-thickness tear (FTT). Comparisons within cohort were performed by Kruskal-Wallis test and between cohorts by Mann-Whitney U-test. Interobserver reliability was performed for Dixon fat fraction and Goutallier grade. PT cohort at baseline showed no difference for age, BMI, CCI, and ASES score; supraspinatus FI was highest for FTT by Goutallier grade (no tear, 0.5 ± 0.5; PTT, 1.1 ± 0.2; and FTT, 1.5 ± 0.5; P = 0.033) and by Dixon fat fraction (no tear, 4.6% ± 1.4%; PTT, 6.1% ± 1.9%; and FTT, 6.7% ± 2.5%; P = 0.430). Control cohort at baseline showed no difference for age, BMI, CCI, and ASES score; supraspinatus FI was highest for supraspinatus FTT by Dixon fat fraction (no tear, 5.8% ± 1.2%; PTT, 7.1% ± 6.3%; and FTT, 21.4% ± 10.4%; P = 0.034) and by Goutallier grade (no tear, 0.8 ± 0.5; PTT, 1.0 ± 0.6; and FTT, 2.4 ± 1.7; P = 0.141). No difference between similar PT and control cohort subgroups at baseline except no tear groups for ASES score (PT cohort, 58.9 ± 8.2; control cohort, 84.0 ± 21.9; P = 0.049). No differences were identified for Δ-Dixon fat fraction and Δ-Goutallier grade over time in the PT and control cohorts. PT cohort no tear subgroup showed significant improvement (P = 0.042) for Δ-ASES score over time relative to PTT and FTT subgroups; no difference for Δ-ASES score over time in the control cohort. Full-thickness RC tear showed higher levels of FI relative to PTT or no tear at baseline. Our pilot study's trend suggested that older adults receiving PT for initial management of RC tear have full-thickness RC tear for shorter duration based on relative lower levels of FI at baseline as compared to older adult volunteers with full-thickness RC tear. Our pilot study also found that older adults in the PT cohort with no tear had superior shoulder functional recovery by ASES score over time relative to full-thickness and PTTs.

A prospective observational case control study investigating the coronal plane scapular morphological differences in full-thickness posterosuperior cuff tears and primary glenohumeral osteoarthritis.

The critical shoulder angle (CSA) is a surrogate marker of the coronal plane morphology of the scapula. CSA differences between scapulae could be due to differences in glenoid inclination (GI) or the location of the most lateral part of the acromion relative to the inferior glenoid, or both. An understanding of the hierarchy of the scapular morphological changes associated with glenohumeral osteoarthritis (GHOA) and rotator cuff (RC) tears would allow accurate biomechanical modeling. A prospective observational case control study was undertaken in which the GI, "nonglenoid"-CSA, acromial vertical offset index, acromial horizontal offset index, acromial horizontal-vertical offset index, and coronal plane angulation of the acromion (CPAA-m) were measured on high-quality radiographs to compare coronal plane scapular anatomy in: (1) patients with asymptomatic atraumatic full-thickness RC tears, (2) patients with symptomatic primary GHOA, and (3) a control group with no RC tear or GHOA treated for glenohumeral instability or symptomatic labral pathology. Intraobserver reliability of the measurements was performed. In the GHOA group, the GI was lower (less superiorly inclined) than the RC tear group (difference between the means: -4.8°, 95% confidence interval [CI] [-8.8°, -0.9°], P = .014) and the control group (difference between the means: -7.9°, 95% CI [-11.8°, -3.9°], P = .000); there was no difference in the acromial measurements. In the RC tear group, the nonglenoid-CSA was higher (difference between the means: 7.7°, 95% CI [3.0°, 12.3°], P = .001), the acromial vertical offset index was lower (difference between the means: -0.13, 95% CI [-0.24, -0.01], P = .026), and the acromial horizontal-vertical offset index was higher (difference between the means: 0.15, 95% CI [0.01, 0.28], P = .030) than the control group; there was no difference in the acromial horizontal offset index or the GI. The CPAA-m was lower (greater coronal plane downslope of the acromion) in both GHOA (difference between the means: -9.6°, 95% CI [-18.6°, -0.5°], P = .036) and RC tears (difference between the means: -9.9°, 95% CI [-19.0°, -0.9°], P = .029) compared with the control group. The intraclass correlation coefficients for intraobserver reliability demonstrated excellent reliability for the measurements (all >0.900). Scapulae associated with GHOA have lower GI, but no spatial differences in the location of the lateral acromion compared with a normal population. Scapulae associated with RC tears have a lower vertical offset of the lateral acromion, but no difference in horizontal offset or GI compared with a normal population. The downslope of the acromion in the coronal plane is greater (lower CPAA-m) in both RC tears and GHOA than the normal population.

ROTATOR MANŞET YIRTIKLARINDA BİSEPS TENDON PATOLOJİLERİNİN SAPTANMASINDA PREOPERATİF MR’IN ETKİNLİĞİ: MR VE İNTRAOPERATİF BULGULARIN KORELASYONU

Objective&#x0D; The aim of this study is to evaluate the accuracy&#x0D; of magnetic resonance imaging (MRI) in detecting&#x0D; biceps lesions in patients with rotator cuff tears.&#x0D; Material and Methods&#x0D; A total of 168 patients operated on between January&#x0D; 2012 and February 2020 were included in the study.&#x0D; All the patients underwent arthroscopic surgery&#x0D; with the diagnosis of rotator cuff tears. All patients&#x0D; were operated on under general anesthesia and&#x0D; in the beach chair position. Demographic data and&#x0D; preoperative MRI findings were recorded. Arthroscopic&#x0D; findings were accepted as the standard reference and&#x0D; correlated with preoperative MRI records.&#x0D; Results&#x0D; In preoperative images, full-thickness rotator cuff&#x0D; tears were identified in 118 (70.2%) cases and partialthickness&#x0D; tears in 50 (29.8%) cases. Labrum/SLAP&#x0D; lesions were detected in 18 (10.7%) cases. Biceps&#x0D; disorders were reported in 51 (30.4%) cases. During&#x0D; the surgeries, we observed additional pathologies in&#x0D; 41 (24.4%) cases besides the preoperatively detected&#x0D; lesions. Rotator cuff and labrum/SLAP repairs were&#x0D; performed in the same surgical sessions. The majority&#x0D; of newly detected lesions were biceps lesions, being&#x0D; identified in 26 (15.5%) cases. In 41 (24.2%) cases&#x0D; tenodesis, tenolysis, or tenotomy were performed&#x0D; for biceps lesions. LHBT surgery was performed in&#x0D; 26 cases with negative MRI. Biceps lesions were&#x0D; confirmed in 77 (45.8%) cases intraoperatively;&#x0D; therefore, the accuracy of MRI in detecting these&#x0D; lesions was 66.2%.&#x0D; Conclusion&#x0D; Biceps lesions are among the common pathologies&#x0D; of the shoulder. Preoperative MRI is important in&#x0D; evaluation of the shoulder, but the efficacy of MRI may&#x0D; be limited in detecting biceps disorders. Arthroscopic&#x0D; surgery is crucial in diagnosis and treatment of LHBT&#x0D; lesions.

Prevalence of Os Acromiale in Thai Patients With Shoulder Problems: A Magnetic Resonance Imaging Study.

Background:Os acromiale is an anatomic variant in which the acromial ossification center fails to fuse. It may lead to painful shoulder conditions and surgical intervention may be required for treatment. The prevalence of os acromiale in South Koreans (0.7%) has previously been the representative number for the Asian population, and it is lower than that in the Black and White populations.Purpose:To determine the prevalence of os acromiale in Thai patients with shoulder disabilities who underwent magnetic resonance imaging (MRI).Study Design:Cross-sectional study; Level of evidence, 3.Methods:We retrospectively reviewed the MRI scans of patients with shoulder disabilities between January 2019 and May 2021 at a single institution. The relationship of sex, age, and shoulder diagnosis to the presence of os acromiale was then analyzed.Results:A total of 940 MRI scans in 848 patients were evaluated, of which 20 shoulders were detected to have os acromiale, a prevalence of 2.13%. The mean age of the patients was 60.25 years, with 60% being female and 40% male. Of the 20 os acromiale cases, 17 (85%) were preacromiale, 1 (5%) mesoacromiale, and 2 (10%) meta-acromiale. The associated diagnoses were as follows: 75%, full-thickness rotator cuff (RC) tear; 10%, partial-thickness RC tear; 5%, RC tendinopathy with symptomatic os acromiale; 5%, anterior shoulder instability with full-thickness RC tear; and 5%, frozen shoulder. Age, sex, and associated shoulder disability were not associated with the presence of os acromiale.Conclusion:In Thai patients with shoulder problems who required MRI evaluation, the prevalence of os acromiale was 2.13%. This is lower than the prevalence from other ethnic groups but slightly higher than that from the same ethnic group (Korea). There was no relation between the presence of os acromiale and shoulder pain, regardless of diagnosis.

Retear rates after rotator cuff surgery: a systematic review and meta-analysis

BackgroundRotator cuff retear (RCR) is one of the main postoperative drawbacks. RCR can be considered a multifactorial issue, which causes are related either to biological than biomechanical factors. The aim of this study was to define the incidence of RCR after surgical treatment at different time points and to identify the main factors influencing the postoperative rotator cuff (RC) healing.MethodsA systematic review and meta-analysis were performed following the PRISMA guidelines. A comprehensive search of the literature was carried out in July 2020, using PubMed and Cochrane Library databases. Only level 1 and 2 clinical evidence studies were included. Studies were included if patients with preoperative repairable full-thickness RC tears were treated surgically, and if studies reported postoperative RCR confirmed by imaging diagnostic. The association between timing of retear and follow-up time points were investigated using an inverse-variance method of pooling data. A subgroup meta-analysis was performed using the DerSimonian and Laird method for the estimation of the between-study variance, i.e., τ2. The association between retear rate after surgery and patients’ age, preoperative tear size, fatty infiltration, postoperative rehabilitation protocol, surgical techniques, and RC repairs was determined by expressing the effect measure in terms of odds ratio (OR) with 95% confidence interval (CI). The Mantel-Haenszel method with 95% CIs was used.ResultsThirty-one articles were included in this study. The percentage of RCR after surgery was 15% at 3 months follow-up, 21% at 3–6 months follow-up, 16% at 6–12 months follow-up, 21% at 12–24 months follow-up, 16% at follow-up longer than 24 months. The main factors influencing RC healing are both patient-related (i.e., age, larger tear size, fatty infiltration) and not patient-related (i.e., postoperative rehabilitation protocol, surgical techniques, and procedures).ConclusionsPostoperative RC healing is influenced by patient-related and non-patient-related factors. Further high-level clinical studies are needed to provide highly relevant clinical results.

High Critical Shoulder Angle Values Are Associated With Full-Thickness Posterosuperior Cuff Tears and Low Values With Primary Glenohumeral Osteoarthritis

To compare critical shoulder angle (CSA) measurements using high-quality radiographs in the following groups: Group 1: symptomatic atraumatic full-thickness rotator cuff (RC) tears; Group 2: symptomatic primary glenohumeral osteoarthritis (GHOA); and Group 3: no RC tear or primary GHOA being treated for glenohumeral instability or symptomatic labral pathology (control group). A prospective observational case control study with 10 shoulders in each group was performed GHOA and full-thickness RC tears were diagnosed by radiographs and magnetic resonance imaging (MRI). For these three groups, the exclusion criteria were the following: Group 1) partial thickness RC tears, traumatic RC tears, isolated subscapularis tears, and advanced cuff tear arthropathy with erosion of the superior glenoid; Group 2) secondary causes of glenohumeral arthritis; coexistent full-thickness RC tear; and Group 3) glenoid bone lesions that may affect the CSA measurement. Only shoulders with adequate radiographic quality (Suter-Henninger type A and C) were eligible. A one-way ANOVA, followed by Tukey multiple pairwise-comparisons test, was performed to compare the groups. Interobserver and intraobserver reliability was assessed using Intraclass Correlation Coefficients (ICC). Mean CSA values were 37.4° ± 4.7 (RC tear group), 28.9° ± 2.4 (GHOA group), and 32.8° ± 1.1 (control group). The CSA of the RC group was higher than the control group (P= .006) and the GHOA group (P= .000). The CSA of the GHOA group was lower than the control group (P= .027). Intraobserver and interobserver reliabilities for the CSA measurement were excellent (Observer 1 [ICC]: .986 [95% CI .970-.993]; Observer 2 [ICC]: .976[95% CI .951-.989]; and Observer 1v2: 0.968[95% CI .933-.985]). There is a difference in the CSA between patients with symptomatic atraumatic full-thickness RC tears (4.6° higher than the control group), symptomatic GHOA (3.8° lower than the control group), and glenohumeral instability or labral pathology with no RC tear or GHOA. Level 2, prospective observational case control diagnostic study.

Preoperative Fatty Infiltration of the Teres Minor Negatively Affects Postoperative Outcomes in Patients With Rotator Cuff Pathology.

Background:The teres minor is a critical component of the rotator cuff and serves as one of the few external rotators of the humerus. Information is lacking regarding the effect of teres minor atrophy in isolation and in the setting of concomitant full-thickness rotator cuff tears on outcomes in patients undergoing rotator cuff surgery.Purpose:To investigate the effect of preoperative teres minor fatty infiltration on postoperative clinical outcomes in patients with and without full-thickness rotator cuff pathology.Study Design:Cohort study; Level of evidence, 3.Methods:A retrospective review of patients undergoing primary arthroscopic shoulder surgery between 2014 and 2016 was performed. Preoperative magnetic resonance imaging was used to determine fatty infiltration for each rotator cuff muscle using the modified Goutallier classification. American Shoulder and Elbow Surgeons (ASES) as well as the shortened version of Disabilities of the Arm, Shoulder and Hand (QuickDASH) scores were obtained preoperatively and during follow-up. Exclusion criteria included prior surgery on the ipsilateral shoulder or a diagnosis of inflammatory arthropathy. For analysis, patients were dichotomized to grade 0 or grade 1-4 atrophy of the teres minor as well as to full-thickness or partial-thickness rotator cuff pathology.Results:A total of 36 of 47 (76.6%) patients (mean age, 63 years; range, 45-76 years) were available for postoperative follow-up at a mean of 40 months (range, 30-48 months). Postoperative ASES score was significantly higher and QuickDASH score was significantly lower among all patients in the grade 0 group compared with the grade 1-4 group. Postoperative ASES and QuickDASH scores were not significantly different in patients with partial-thickness rotator cuff tears at any time point. However, the postoperative ASES score was significantly higher and QuickDASH score was significantly lower in the grade 0 versus grade 1-4 group for patients with full-thickness rotator cuff pathology.Conclusion:Preoperative teres minor atrophy in patients undergoing surgery for rotator cuff pathology may impair postoperative clinical outcomes, especially in patients with full-thickness tears.

Human Rotator Cuff Tears Have an Endogenous, Inducible Stem Cell Source Capable of Improving Muscle Quality and Function After Rotator Cuff Repair

Background: The muscle quality of the rotator cuff (RC), measured by atrophy and fatty infiltration (FI), is a key determinant of outcomes in RC injury and repair. The ability to regenerate muscle after repair has been shown to be limited. Purpose: To determine if there is a source of resident endogenous stem cells, fibroadipogenic progenitor cells (FAPs), within RC injury patients, and if these cells are capable of adipogenic, fibrogenic, and pro-myogenic differentiation. Study Design: Controlled laboratory study. Methods: A total of 20 patients between the ages of 40 and 75 years with partial- or full-thickness RC tears of the supraspinatus and evidence of atrophy and FI Goutallier grade 1, 2, or 3 were selected from 2 surgeons at an orthopaedic center. During the surgical repair procedure, supraspinatus muscle biopsy specimens were obtained for analysis as were deltoid muscle biopsy specimens to serve as the control. FAPs and satellite cells were quantified using fluorescence-activated cell sorting. Muscle FI and fibrosis was quantified using Oil Red O and Masson trichrome staining. FAP differentiation and gene expression profiles were compared across tear sizes after culture in adipogenic, fibrogenic, and beta-3 agonist (amibegron) conditions. Analysis of variance was used for statistical comparisons between groups, with P < .05 as statistically significant. Results: Histologic analysis confirmed the presence of fat in biopsy specimens from patients with full-thickness tears. There were more FAPs in the full-thickness tear group compared with the partial-thickness tear group (9.43% ± 4.25% vs 3.84% ± 2.54%; P < .01). Full-thickness tears were divided by tear size, with patients with larger tears having significantly more FAPs than those with smaller tears. FAPs from muscles with full-thickness tendon tears had more adipogenic and fibrogenic potential than those with partial tears. Induction of a beige adipose tissue (BAT) phenotype in FAPs was possible, as demonstrated by increased expression of BAT markers and pro-myogenic genes including insulin-like growth factor 1 and follistatin. Conclusion: Endogenous FAPs are present within the RC and likely are the source of FI. These FAPs were increased in muscles with in larger tears but are capable of adopting a pro-myogenic BAT phenotype that could be utilized to improve muscle quality and patient function after RC repair.

Inducible endogenous stem cells within human rotator cuff muscle to promote muscle regeneration after rotator cuff repair

Objectives:Rotator cuff (RC) tears are the most common upper extremity injury, with over two million Americans seeking medical attention annually. Secondary muscle degradation following RC tears, including atrophy and fatty infiltration (FI), are critical factors that directly determine the clinical outcome of patients with this injury In mouse studies, the importance of fibro/adipogenic (FAP) cells in the development of FI after RC tears has been shown, determining that these cells are the predominant cell line responsible for the development of FI. FAP cells have garnered considerable interest in mediating both positive and negative effects on muscle cells. In regenerative conditions, FAPs stimulate satellite cell (SC) growth and differentiation, but in degenerative states, these cells differentiate into fat and fibrotic tissue. Additionally, FAPs have the ability to express factors consistent with beige fat, which may have important regenerative potential. In this study, we harvested samples from supraspinatus muscle in patients undergoing RC repair to determine for 1) the presence of FAP cells; 2) the presence of satellite cells; and 3) the ability of FAPs to differentiate into fat and/or fibrotic tissue. We hypothesized that both FAPs and SC would increase, and FAPs would display considerable cell plasticity and have the ability to differentiate into beige fat, adipocytes, and fibroblasts.Methods:The study was approved by the institutional IRB. At the time of surgery, a 3mm × 3 mm Supraspinatus (SS) and Deltoid (DL) biopsy was collected during surgery from 20 different clinical cases (Average age was 65 years, with 15 men and 5 women). Half of the biopsy was used for histology and half for Flow cytometry. For the vitro analysis, FAPs were isolated from human specimens using BD Aria II with PI live and Dead staining, and further isolated using CD31-, CD45-, CD184-, CD29-. CD56-, CD34+, CD140a + markers. SCs were sorted with PI live and dead staining, and further isolated using CD31-, CD45-, CD184+, CD29-, CD56+, CD34-, CD140a + markers. FAPs were cultured in 24 wells cell culture plates in standard media (F10+20%FBS+1% Antibiotics), Fibrogenic media (10ng/ml TGFβ-1) and Adipogenic media (stempro kit) for 2 weeks. For the Amibegron treatment group, FAPs were cultured in adipogenic media for 2 weeks first and switch to Adipogenic media with 10uM Amibegron (Sigma). FAPs were fixed with 4% PFA and stained with collagen I for quantify fibrosis index and perilipin A for Adipogenic index. The Paired ANOVA was used for statistical comparisons between groups, with p<0.05. Data are presented as mean +/- standard deviation.Results:A total of 20 patients were included in the study with different tear sizes. While SC number did not increase when comparing tear sizes, FAP cell number increased with increasing tear sizes. Patients with RC tears all had significantly more FAPs (7.8+/-2% vs 1.3 +/- .4%, p<0.05) compared to patients with partial tears. When divided by tear size, patients with medium and large tears had more FAPs compared to partial and small tears, a difference that was statistically significant. Histological analysis demonstrated that muscle architecture was preserved, but those with full thickness tears had more fat and fibrosis, with increased FAPs (Stained Red, Figure 2). FAPs from patients with full thickness tears had increased ability to differentiate into adipocytes and fibroblasts compared to partial tears (Figure 3), and had increased expression of UCP-1 (P<0.05). FAPs that were isolated from full thickness tears demonstrated increased expression of several promyogenic factors including IGF-1 and follistatin.Conclusions:Patients with full thickness RC tears have increased FAPs compared to control muscle and partial tears. FAPs from full thickness tears increase with tear size and have more differentiation potential compared. This data confirms that these cells are likely the cellular source for FI in humans, but that they also may serve a regenerative potential as they show differentiation plasticity and expression markers consistent with a beige fat phenotype. The fact that FAPS are able to differentiate and express pro-myogenic factors such as IGF-1 and follistatin suggest that they may serve as an endogenous stem cell source for improving muscle quality after RC repair.

The Critical Shoulder Angle Shows a Reciprocal Change in Magnitude When Evaluating Symptomatic Full-Thickness Rotator Cuff Tears Versus Primary Glenohumeral Osteoarthritis as Compared With Control Subjects: A Systematic Review and Meta-analysis

To determine whether a high critical shoulder angle (CSA) is associated with symptomatic full-thickness rotator cuff (RC) tears and/or whether a low CSA is associated with primary glenohumeral osteoarthritis (GHOA). A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All observational studies that examined an association between CSA and full-thickness RC tears and/or primary GHOA were included. A primary meta-analysis was performed including all studies that met the inclusion criteria regardless of radiographic quality. A secondary meta-analysis was performed to explore the hypothesis that radiographic quality was a source of heterogeneity, which excluded those studies in which radiograph quality was not strictly defined and controlled. For the primary meta-analysis, 11 studies met the inclusion criteria for RC tears and 5 for primary GHOA. The CSA was greater in the RC tear group than the control group (mean difference 4.03°, 95% confidence interval 2.95°-5.11, 95% prediction interval 0.0487°-8.01°; P < .001). The CSA was lower in the GHOA group than the control group (mean difference -3.98°, 95% confidence interval -5.66° to -2.31°, 95% prediction interval -10.2° to -2.19°; P < .001).A high level of heterogeneity was observed in the RC tear analysis (I2= 88.4), which decreased after the exclusion of 5 studies based on radiographic quality (I2= 75.3). A high level of heterogeneity also was observed in the primary GHOA analysis (I2= 87.3), which decreased after the exclusion of 2 studies based on the radiographic quality (I2= 48.2). There is a reciprocal change in magnitude of the CSA when evaluating symptomatic full-thickness RC tears versus primary GHOA as compared with control subjects. Radiographic quality is a source of heterogeneity in studies that investigate a link between CSA and RC tears and primary GHOA. Level III, systematic review and meta-analysis of Level III studies.

Association of Rotator Cuff Tear Patterns and Intramuscular Fatty Infiltration on Magnetic Resonance Imaging.

Objective:The impact of rotator cuff (RC) tear pattern on intramuscular fatty infiltration (FI) is not well understood. The purpose of our study is to determine if differing RC tear patterns are associated with discordant presentations of intramuscular FI.Methods:Fifty-one adults with full-thickness tear of the posterosuperior RC on shoulder magnetic resonance imaging (MRI) were identified retrospectively. The study subjects were stratified by RC tear pattern: (1) L-shaped tear cohort, (2) crescent-/U-shaped tear cohort, and (3) complete tear cohort. Clinical information pertaining to age, sex, tear size, trauma history, and length of clinical symptoms was recorded from the institution’s picture archiving and communication system. Goutallier grade was assessed on oblique sagittal T1-weighted MRI by two orthopedic surgeons and one orthopedic resident. A musculoskeletal radiologist recorded the shape and size of full-thickness RC tears. Descriptive, correlation, and reliability analyses were performed.Results:The L-shaped, crescent-/U-shaped, and compete tear cohorts demonstrated significant differences pertaining to tear size (P < 0.001) and infraspinatus Goutallier grade (P = 0.024), but not supraspinatus Goutallier grade (P = 0.370). Age had strong correlation to supraspinatus Goutallier grade (rs = 0.712, P = 0.031) and infraspinatus Goutallier grade (rs = 0.712, P = 0.029) in the crescent-/U-shaped tear cohort. Tear size had strong correlation to supraspinatus Goutallier grade (rs = 0.796, P = 0.001) and infraspinatus Goutallier grade (rs = 0.793, P = 0.001) in the complete tear cohort. Moderate interobserver agreement was present for supraspinatus (kappa, 0.484) and infraspinatus (kappa, 0.427) Goutallier grade.Conclusion:RC tear pattern is associated with different presentations of intramuscular FI at the posterosuperior RC. Full-thickness tears involving the crescent region of the RC cuff are associated with age. Intramuscular FI is associated with RC tear size.

Une technique arthroscopique pour la réparation des ruptures complètes de la coiffe des rotateurs par transposition de la longue portion du biceps

Arthroscopic rotator cuff (RC) repair is now considered as an effective treatment for patients with symptomatic rotator cuff tears. We reported a new method for repairing a full-thickness RC tear by using the double-row technique with transposition of the long head of biceps (LHB). The novelty of this technique is using the long head of the biceps as an augmentation. The indication of this technique consists of two aspects including LHB lesions and RC tears. Three patients were enrolled. An ideal reconstruction of the anatomic footprint of the tendon and stabilization of glenohumeral joint was achieved after the double-row technique with the transposition of the long head of biceps. At 6-month postoperation, the mean VAS score was 1.23±0.15 and the mean Constant score was 88.00±9.17. Transposition of the long head of biceps is a choice for full-thickness RC tear. Level of evidenceIV, case series.

Early Active Motion Versus Sling Immobilization After Arthroscopic Rotator Cuff Repair: A Randomized Controlled Trial

To compare the effect of early mobilization (EM) with standard rehabilitation (SR) over the initial 24months following arthroscopic rotator cuff (RC) repair. A total of 206 patients with full-thickness RC tears undergoing arthroscopic repair were randomized following preoperative assessment of shoulder range of motion (ROM), pain, strength, and health-related quality of life (HRQOL) to either EM (n= 103; self-weaned from sling and performed pain-free active ROM during the first 6weeks) or SR (n= 103; wore a sling for 6weeks with no active ROM). Shoulder ROM, pain, and HRQOL were reassessed at 6weeks and 3, 6, 12, and 24months postoperatively by a blinded assessor. At 6, 12, and 24months, strength was reassessed. At 12months, ultrasound verified RC integrity. Independent t tests assessed 6-week group differences and 2-way repeated measures analysis of variance assessed changes over time between groups. The groups were similar preoperatively (P > .12). The mean age of participants was 55.9 (minimum, 26; maximum, 79) years, and 131 (64%) were men. A total of 171 (83%) patients were followed to 24months. At 6weeks postoperatively, EM participants had significantly better forward flexion and abduction (P < .03) than the SR participants; no other group differences were noted. Over 24months, there were no group differences in ROM after 6weeks (P > .08), and pain (P > .06), strength (P= .35), or HRQOL (P > .20) at any time. Fifty-two (25%) subjects (30% EM; 33% SR) had a full-thickness tear present at 12-month postoperative ultrasound testing (P > .8). EM did not show significant clinical benefits, but there was no compromise of postoperative ROM, pain, strength, or HRQOL. Repair integrity was similar at 12months postoperatively between groups. Consideration should be given to allow pain-free active ROM within the first 6weeks following arthroscopic RC repair. Level I, high-quality randomized controlled trial.

An arthroscopic technique for full-thickness rotator cuff repair by transposition of the long head of biceps

Arthroscopic rotator cuff (RC) repair is now considered as an effective treatment for patients with symptomatic rotator cuff tears. We reported a new method for repairing a full-thickness RC tear by using the double-row technique with transposition of the long head of biceps (LHB). The novelty of this technique is using the long head of the biceps as an augmentation. The indication of this technique consists of two aspects including LHB lesions and RC tears. Three patients were enrolled. An ideal reconstruction of the anatomic footprint of the tendon and stabilization of glenohumeral joint was achieved after the double-row technique with the transposition of the long head of biceps. At 6-month postoperation, the mean VAS score was 1.23±0.15 and the mean Constant score was 88.00±9.17. Transposition of the long head of biceps is a choice for full-thickness RC tear. Level of evidenceIV, case series.