Severity Of Rotator Cuff Tears Research Articles

The Effect of Ethanol on Rotator Cuff Repairs in a Rodent Model

BackgroundAlcohol consumption is a significant risk factor for both the occurrence and severity of rotator cuff tears. However, there is limited supporting evidence to suggest alcohol use is associated with suboptimal outcomes following operative repair of rotator cuff tears. Rat shoulders have been demonstrated as consistent and reliable models for studying rotator cuff disease. Hypothesis/PurposePerioperative alcohol exposure will negatively impact biomechanical and histologic properties of surgically repaired rotator cuffs in rats. MethodsRats were randomized to receive a 20% ethanol or isocaloric control solution as their primary source of drinking water. A tenotomy of the supraspinatus tendon from bone was performed surgically and then immediately repaired with a transosseous technique. Following surgery, rats were continued on the same exposure solution until animals were humanely euthanized at 7, 14, or 21 days postoperatively. The surgically-repaired shoulders underwent biomechanical testing to assess load to failure and failure strain. Histological evaluation of tendon-to-bone healing was performed by a blinded pathologist using a qualitative grading system. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) on total RNA from tendon-to-bone interface tissue was performed to quantify the mRNA expression of Type I & III collagen, and transforming growth factor-beta 1 (TGF-B1) & 3 (TGF-B3) at the repair site. ResultsBiomechanical testing showed that repaired shoulder constructs in rats exposed to ethanol had significantly lower load to failure at 7 days postop relative to repairs in rats exposed to a control solution. No other biomechanical parameters or time points reached statistical significance. TGF-B3 mRNA expression was found in significantly higher quantities at the repair sites of rats exposed to ethanol at 7 days postop relative to control rat repair sites. No other time points or factors reached statistical significance. No significant differences were identified amongst time points or groups at the healing tendon-to-bone interface. ConclusionAlcohol exposure significantly decreases biomechanical load to failure of rotator cuff repairs in the early postoperative period in rat models. In the later postoperative period, alcohol exposure was not associated with a decrease in biomechanical load to failure compared to controls. Additionally, rats exposed to ethanol have significantly higher TGF-B3 expression at repair sites on postoperative day 7. This data suggests that ethanol consumption does deleteriously affect rotator cuff and bone healing. Future study is needed to validate the clinical significance of these findings in humans.

The Association between Rotator Cuff Tear Severity on Magnetic Resonance Imaging and Pain Improvement after Referral to Conventional Physical Therapy: A Retrospective Cohort Analysis

The Association between Rotator Cuff Tear Severity on Magnetic Resonance Imaging and Pain Improvement after Referral to Conventional Physical Therapy: A Retrospective Cohort Analysis

Effect of subscapularis repair on joint contact forces based on degree of posterior-superior rotator cuff tear severity in reverse shoulder arthroplasty.

Massive irreparable rotator cuff tears (RCTs) affect the clinical outcomes of reverse shoulder arthroplasty (RSA). However, the effects of subscapularis repair on the outcomes of RSA, based on the degree of posterior-superior RCTs, are unclear. This study aimed to examine the effect of subscapularis repair on three-dimensional joint contact forces (JCFs) based on the degree of posterior-superior RCT severity in RSA. Ten human in vivo experimental data were used as input to the musculoskeletal model. A six-degrees-of-freedom (DOF) anatomical shoulder model was developed and validated against three-dimensional JCFs. The 6-DOF musculoskeletal shoulder model of RSA was then developed by importing the reverse shoulder implant into the validated anatomical shoulder model. Based on the various types of posterior-superior RCT severity, inverse dynamic simulations of subscapularis-torn and subscapularis-repaired models of RSA were performed: from isolated supraspinatus tears to partial or massive tears of the infraspinatus and teres minor. The intact rotator cuff model of RSA was also simulated for comparison with the different types of models. Our results showed that the more posterior-superior RCTs progressed in RSA, the more superior JCFs were observed at 90°, 105°, and 120° abduction in the subscapularis-torn model. However, subscapularis repair decreased the superior JCF at those angles sufficiently. In addition, the teres minor muscle-tendon force increased as infraspinatus bundle tears progressed in both the subscapularis-torn and -repaired models, in order to compensate for the reduced force during abduction. However, the teres minor muscle-tendon force was not as high as that of the infraspinatus muscle-tendon, which could result in muscle force imbalance between repaired subscapularis and teres minor. Therefore, our results suggest that repairing the subscapularis and the repairable infraspinatus during RSA can improve glenohumeral joint stability in the superior-inferior direction by restoring muscle force balance between the anterior cuff (i.e., subscapularis) and posterior cuff (i.e., infraspinatus and teres minor). The findings of this study can help clinician decide whether to repair the rotator cuff during RSA to enhance joint stability.

Influence of body mass index on severity of rotator cuff tears

Research on the relationship between obesity and rotator cuff tears (RCTs) has been limited to the impact of obesity on the results of arthroscopic repair of RCTs; thus, a need for rigorous research controlling for other factors affecting RCTs is warranted, especially to better understand the impact of body mass index (BMI) on RCT severity. A retrospective study of admission records contained in electronic medical records pertaining to patients who were admitted for RCT repair on one shoulder between January 2018 and July 2022 was conducted. In total, 386 patients were included. In accordance with guidance regarding obesity from Taiwan's Ministry of Health and Welfare, patients were divided into three groups: underweight or normal weight (BMI <24.0 kg/m2), overweight (BMI 24.0-26.9 kg/m2), or obese (BMI ≥27.0 kg/m2). Magnetic resonance imaging (MRI) was used to assess RCT severity in terms of four parameters: Patte stage (PS), fatty infiltration (FI), anteroposterior tear size (AP), and retraction size. Multinomial logistic regression analysis was performed on Patte stage and FI grade data, and multiple linear regression analysis was performed on AP tear size and retraction size in order to analyze impact. Our results revealed that the average age of the 386 patients was 63.41 years (SD = 9.29) and the mean BMI was 25.88 (SD = 3.72) kg/m2. We found significant differences in PS (p =.003), FI (p <.001), retraction size (p =.001), and AP tear size (p =.001) among patients who were underweight or normal weight, overweight, and obese. After controlling for other risk factors, including age, gender, RCT-prone occupation, duration of shoulder pain prior to surgery, history of shoulder injury, and tobacco use, we found that obese patients had higher severity levels in PS (B = 1.21, OR = 3.36, p = .029), FI (B = 1.38, OR = 3.96, p < .001), retraction size (β = .18, p = .001), and AP tear size (β = .18, p = .001) compared to underweight or normal weight patients. Our study demonstrates that a correlation exists between BMI-measured obesity and RCT severity. We therefore suggest that adults control their weight given that maintaining a healthy weight is highly associated with better shoulder health.

Movement compensation is driven by the deltoid and teres minor muscles following severe rotator cuff tear

BackgroundRotator cuff tears are common in older adults, negatively affecting function. Previous simulation-based studies reported more posterior and superior oriented glenohumeral loading with increased cuff tear severity and task performance, although corresponding muscle compensation strategies are unclear. Our objective is to determine how shoulder muscle forces change with increased rotator cuff tear severity during functional task performance. MethodsEight musculoskeletal models of increasing tear severity were developed to represent no rotator cuff tear to massive three-tendon tears. Simulations were performed using each combination of model and kinematics for five functional tasks. Individual muscle forces were averaged for each task and tear severity, then normalized by the sum of the muscle forces across the shoulder. Forces were compared across tear severity and muscle. FindingsFor muscle force contribution, interactions between tear severity and muscle and a main effect of muscle were seen for all tasks (P < 0.0001). Middle deltoid increased force contribution by >10% in the greatest tear severity model compared to no cuff tear model for all tasks (all P < 0.0001). Teres minor contribution increased by 7.7%, 5.6%, and 11% in the greatest tear severity model compared to the no cuff tear model for forward reach, axilla wash, and upward reach 105° tasks, respectively (all P < 0.0001). InterpretationFunctional tasks elicit compensatory responses from uninjured muscles following severe cuff tears, notably in middle deltoid and teres minor, leading to posterior-superior glenohumeral loading. The muscles are potential targets for strengthening to avoid injury from sustained increased muscle force.

Risk factors of chronic subscapularis tendon tear.

Chronic subscapularis tendon tear (SBT) is a degenerative disease and a common pathologic cause of shoulder pain. Several potential risk factors for chronic SBT have been reported. Although metabolic abnormalities are common risk factors for degenerative disease, their potential etiological roles in chronic SBT remains unclear. The purpose of this study was to investigate potential risk factors for chronic SBT, with particular attention to metabolic factors. This study evaluated single shoulders of 939 rural residents. Each subject undertook a questionnaire, physical examinations, blood tests, and simple radiographs and magnetic resonance imaging (MRI) evaluations of bilateral shoulders. Subscapularis tendon integrity was determined by MRI findings based on the thickness of the involved tendons. The association strengths of demographic, physical, social, and radiologic factors, comorbidities, severity of rotator cuff tear (RCT), and serologic parameters for SBT were evaluated using logistic regression analyses. The significance of those analyses was set at p<0.05. The prevalence of SBT was 32.2% (302/939). The prevalence of partial- and full-thickness tears was 23.5% (221/939) and 8.6% (81/939), respectively. The prevalence of isolated SBT was 20.2% (190/939), SBT combined with supraspinatus or infraspinatus tendon tear was 11.9% (112/939). In multivariable logistic regression analysis, dominant side involvement (p<0.001), manual labor (p=0.002), diabetes (p<0.001), metabolic syndrome (p<0.001), retraction degree of Patte tendon (p<0.001), posterosuperior RCT (p=0.010), and biceps tendon injury (p<0.001) were significantly associated with SBT. Metabolic syndrome is a potential risk factor for SBT, as are these factors: overuse activity, diabetes, posterosuperior RCT, increased retraction of posterosuperior rotator cuff tendon, and biceps tendon injury.

The robustness of glenohumeral centering measurements in dependence of shoulder rotation and their predictive value in shoulders with rotator cuff tears

ObjectiveDe-centering of the shoulder joint on radiographs is used as indicator for severity of rotator cuff tears and as predictor for clinical outcome after surgery. The objective of the study was to assess the effect of malrotation on glenohumeral centering on radiographs and to identify the most reliable parameter for its quantification.Subjects and methods.In this retrospective study (2014–2018), 249 shoulders were included: 92 with imaging-confirmed supra- and infraspinatus tears (rupture; 65.2 ± 9.9 years) and 157 without tears (control; 41.1 ± 13.0 years). On radiographs in neutral position and external rotation, we assessed three radiographic parameters to quantify glenohumeral centering: acromiohumeral distance (ACHD), craniocaudal distance of the humeral head and glenoid center (Deutsch), and scapulohumeral arch congruity (Moloney). Non-parametric statistics was performed.ResultsIn both positions, only the distance parameters ACHD (< 0.5 mm) and Deutsch (< 1 mm) were comparable in the two study groups rupture and control. Comparing the parameters between the study groups revealed only ACHD to be significantly different with a reduction of more than 2 mm in the rupture group. Among the parameters, ACHD ≤ 6 mm was the only cut-off discriminating rupture (12–21% of the shoulders with ACHD ≤ 6 mm) and control (none of the shoulders with ACHD ≤ 6 mm). Ninety percent of shoulders with ACHD ≤ 6 mm presented with a massive rotator cuff tear (defined as ≥ 67% of the greater tuberosity exposed).ConclusionGlenohumeral centering assessed by ACHD and Deutsch is not affected by rotation in shoulders with and without rotator cuff tear. An ACHD ≤ 6 mm has a positive predictive value of 90% for a massive rotator cuff tear.

Macroscopic aspects of glenohumeral synovitis are related to rotator cuff tear severity.

The microscopic pattern of inflammatory mediators associated with rotator cuff pathology is well documented; however, little is known regarding the contemporary presence of macroscopic inflammatory joint involvement. Our aim was to investigate shoulder synovitis in a large group of patients with different sized rotator cuff tears (RCTs) and to correlate the degree of macroscopic inflammatory changes of the glenohumeral joint with RCT severity. A total of 296 consecutive patients (169 F, 127 M; mean age ± standard deviation: 60.75 ± 7.91) submitted to arthroscopic RCT repair were enrolled. RCT was classified intraoperatively. Glenohumeral synovitis was investigated according to 4 parameters (Davis classification 2017: capsule color, villous projections, capillaries, and axillary recess). A total score was calculated, and a 3-grade severity scale was introduced. Statistics was performed. Intraclass correlation coefficient (ICC) results show good to excellent reliability: capsule color (ICC: 0.95; 95% confidence interval [CI]: 0.89-0.99), villous projections (ICC: 0.90; 95% CI: 0.85-0.95), capillaries (ICC: 0.91; 95% CI: 0.86-0.95), and axillary recess (ICC: 0.55; 95% CI: 0.80-0.89).The synovitis total score was found to be 1.47 ± 1.16, 2.86 ± 1.84, and 3.99 ± 1.64 in patients with type I, II, and III RCTs, respectively. A significant difference was found between groups (P < .001). The prevalence of all the examined parameters was found to be significantly different between the different sized RCT groups (capsule color: P < .001; villous projections: P < .001; capillaries: P < .001; and axillary recess: P < .001). According to a 3-grade severity scale, the prevalence of absent, mild, and severe glenohumeral synovitis significantly differed between the RCT severity groups (P < .001). The present study demonstrated that synovitis is a constant finding of rotator cuff pathology; it is present in 75% of patients with RCTs and correlates with tear severity. Whether synovitis is the cause or effect of RCT is still questionable. Further studies are also needed to better understand its role as a pain generator, as documented in other diseases.

Patient-Reported Outcomes Measurements Information System (PROMIS) upper extremity and pain interference do not significantly predict rotator cuff tear dimensions.

BackgroundProper diagnosis of rotator cuff tears is typically established with magnetic resonance imaging (MRI); however, studies show that MRI-derived measurements of tear severity may not align with patient-reported pain and shoulder function. The purpose of this study is to investigate the capacity for the Patient-reported Outcomes Measurements Information System (PROMIS) computer adaptive tests to predict rotator cuff tear severity by correlating preoperative tear morphology observed on MRI with PROMIS upper extremity (UE) and pain interference (PI) scores. This is the first study to investigate the relationship between tear characteristics and preoperative patient-reported symptoms using PROMIS. Considering the essential roles MRI and patient-reported outcomes play in the management of rotator cuff tears, the findings of this study have important implications for both treatment planning and outcome reporting.MethodsTwo PROMIS–computer adaptive test forms (PROMIS-UE and PROMIS-PI) were provided to all patients undergoing rotator cuff repair by one of three fellowship-trained surgeons at a single institution. Demographic information including age, sex, race, employment status, body mass index, smoking status, zip code, and preoperative PROMIS-UE and -PI scores was prospectively recorded. A retrospective chart review of small to large full- or partial-thickness rotator cuff tears between May 1, 2017 and February 27, 2019 was used to collect each patient’s MRI-derived tear dimensions and determine tendon involvement.ResultsOur cohort consisted of 180 patients (56.7% male, 43.3% female) with an average age of 58.9 years (standard deviation, 9.0). There was no significant difference in PROMIS-UE or -PI scores based on which rotator cuff tendons were involved in the tear (P > .05). Neither PROMIS-UE nor PROMIS-PI significantly correlated with tear length or retraction length of the supraspinatus tendon (P > .05). The sum of tear lengths in the anterior-posterior and medial-lateral directions was weakly correlated with PROMIS-UE (P = .042; r = -0.152, r2 = 0.031) and PROMIS-PI (P = .027; r = 0.165, r2 = 0.012).ConclusionRotator cuff tear severity does not significantly relate to preoperative PROMIS-UE and -PI scores. This finding underscores the importance of obtaining a balanced preoperative assessment of rotator cuff tears that acknowledges the inconsistent relationship between rotator cuff tear characteristics observed on MRI and patient-reported pain and physical function.

Glenohumeral joint loading is impacted by rotator cuff tear severity during functional task performance

BackgroundRotator cuff tear is a common musculoskeletal injury, negatively affecting shoulder function. Rotator cuff tear severity ranges from small to massive tears, but it is unclear how tear severity affects glenohumeral joint loading and how changes contribute to secondary injury. This study's objective was to determine how glenohumeral joint contact force changes with tear severity during functional task performance using computational models. MethodsEight models of increasing tear severity were developed, ranging from no rotator cuff tear to massive three-tendon tears. Simulations were performed using models representing increasing tear severity and kinematics for five functional tasks (n = 720 simulations). For each task, magnitude and orientation of peak resultant joint contact force for each tear severity was identified, then compared to the no rotator cuff tear model. FindingsFor all tasks, compared to the no rotator cuff tear model, joint contact force magnitude decreased 9.5% on average with infraspinatus involvement, then plateaued at 20.8% average decrease with subscapularis involvement. Projected orientation of peak joint contact force vector was located more superior in the glenoid with increased tear severity, with significant changes (p < 0.0003) for all tasks with infraspinatus involvement. InterpretationDecreased magnitude and superior orientation of joint contact force suggest fewer intact muscles contribute to force distribution across the joint, although more work is needed characterizing associated compensation strategies. All force vectors remained oriented within the glenoid rim for all tasks and models, suggesting the system prioritizes joint stability. This work identifies how joint contact force changes with rotator cuff tear severity.

Association Between Rotator Cuff Tears and Superior Migration of the Humeral Head: An MRI-Based Anatomic Study.

Background:Superior humeral migration has been established as a component of rotator cuff disease, as it disrupts normal glenohumeral kinematics. Decreased acromiohumeral interval (AHI) as measured on radiographs has been used to indicate rotator cuff tendinopathy. Currently, the data are mixed regarding the specific rotator cuff pathology that contributes the most to humeral head migration.Purpose:To determine the relationship between severity of rotator cuff tears (RCTs) and AHI via a large sample of magnetic resonance imaging (MRI) shoulder examinations.Study Design:Cohort study; Level of evidence, 3.Methods:A search was performed for 3-T shoulder MRI performed in adults for any indication between January 2010 and June 2019 at a single institution. Three orthopaedic surgeons and 1 musculoskeletal radiologist measured AHI on 2 separate occasions for patients who met the inclusion criteria. Rotator cuff pathologies were recorded from imaging reports made by fellowship-trained musculoskeletal radiologists.Results:A total of 257 patients (mean age, 52 years) met the inclusion criteria. Of these, 199 (77%) had at least 1 RCT, involving the supraspinatus in 174 (67.7%), infraspinatus in 119 (46.3%), subscapularis in 80 (31.1%), and teres minor in 3 (0.1%). Full-thickness tears of the supraspinatus, infraspinatus, or subscapularis tendon were associated with significantly decreased AHI (7.1, 5.3, and 6.8 mm, respectively) compared with other tear severities (P < .001). Having a larger number of RCTs was also associated with decreased AHI (ρ = –0.157; P = .012). Isolated infraspinatus tears had the lowest AHI (7.7 mm), which was significantly lower than isolated supraspinatus tears (8.9 mm; P = .047).Conclusion:Although various types of RCTs have been associated with superior humeral head migration, this study demonstrated a significant correlation between a complete RCT and superior humeral migration. Tears of the infraspinatus tendon seemed to have the greatest effect on maintaining the native position of the humeral head. Further studies are needed to determine whether early repair of these tears can slow the progression of rotator cuff disease.

Associations of preoperative patient mental health status and sociodemographic and clinical characteristics with baseline pain, function, and satisfaction in patients undergoing primary shoulder arthroplasty

Shoulder pain and dysfunction are common indications for shoulder arthroplasty, yet the factors that are associated with these symptoms are not fully understood. This study aimed to investigate the associations of patient and disease-specific factors with preoperative patient-reported outcome measures (PROMs) in patients undergoing primary shoulder arthroplasty. We hypothesized that worse mental health status assessed by the Veterans RAND 12-Item Health Survey (VR-12) mental component score (MCS), glenoid bone loss, and increasing rotator cuff tear severity would be associated with lower values for the preoperative total Penn Shoulder Score (PSS) and its pain, function, and satisfaction subscores. We prospectively identified 12 patient factors and 4 disease-specific factors as possible statistical predictors of preoperative PROMs in patients undergoing primary shoulder arthroplasty at a single institution over a 3-year period. Multivariable statistical modeling and Akaikeinformation criterioncomparisons were used to investigate the unique associations with, and relative importance of, these factors in accounting for variation in the preoperative PSS and its subscores. A total of 788 cases performed by 12 surgeons met the inclusion criteria, with a preoperative median total PSS of 31 points (pain, 10 points; function, 18 points; and satisfaction, 1 point). As hypothesized, a lower VR-12 MCS was associated with lower preoperative PSS pain, function, and total scores, but patients with intact status or small to medium rotator cuff tears had modestly lower PSS pain subscores (ie, more pain) than patients with large to massive superior-posterior rotator cuff tears. Glenoid bone loss was not associated with the preoperative PSS. Female sex and fewer years of education (for all 4 outcomes), lower VR-12 MCS and preoperative opioid use (for all outcomes but satisfaction), and rotator cuff tear severity (for pain only) were the factors most prominently associated with preoperative PROMs. In addition to mental health status and rotator cuff tear status, patient sex, years of education, and preoperative opioid use were most prominently associated with preoperative PROMs in patients undergoing shoulder arthroplasty. Further studies are needed to investigate whether these factors will also predict postoperative PROMs.

The relationship between high-signal intensity changes in the glenohumeral joint capsule on MRI and clinical shoulder symptoms

Background/objectiveHigh-signal intensity changes in the glenohumeral joint capsule on T2-and proton density-weighted magnetic resonance imaging are known as characteristic finding that is often observed in patients with frozen shoulder. We investigated the associations between high-signal intensity changes in the joint capsule on magnetic resonance imaging and the presence of rotator cuff tears and shoulder symptoms in patients with shoulder pain. MethodsThe medical records of 230 patients with shoulder pain who underwent magnetic resonance imaging at our hospital were reviewed. Patients were divided into three groups according to the presence and/or degree of rotator cuff tears (none, partial, or complete). The frequency of high-signal intensity changes in the joint capsule and its relationship with shoulder symptoms and the severity of rotator cuff tears were assessed. By quantitatively evaluating the intensity on MRI, the ratio between the joint capsule and the long head of the biceps (HSIC ratio) was calculated and compared with 15 healthy subjects. ResultsHigh-signal intensity changes were diagnosed in 165 (72%) patients, and it was significantly associated with night pain and range of motion limitation (p < 0.01). High-signal intensity changes were present in 66 patients (70%) with no rotator cuff tears, in 69 (71%) with partial rotator cuff tears, and in 36 (80%) with complete rotator cuff tears, without differences in their occurrence (p = 0.60), but were significantly associated with night pain in all the groups (p < 0.01) without differences in tear severity (p = 0.63). The ratio in the high-signal intensity changes (HSIC) positive group was approximately six times higher than that in the HSIC-negative and control groups (P < 0.01). Multivariate logistic regression analysis revealed that night pain is significantly associated with high-signal intensity changes (p < 0.01). ConclusionShoulder pain is a common and reliable clinical finding in patients with high–signal intensity changes, regardless of the presence and/or degree of rotator cuff tears, Such changes may indicate night pain and range of motion limitation in patients.

Muscle compensation strategies to maintain glenohumeral joint stability with increased rotator cuff tear severity: A simulation study

Rotator cuff tear (RCT) in older adults may cause decreased muscle forces and disrupt the force balance at the glenohumeral joint, compromising joint stability. Our objective was to identify how increased RCT severity affects glenohumeral joint loading and muscle activation patterns using a computational model. Muscle volume measurements were used to scale a nominal upper limb model’s peak isometric muscle forces to represent force-generating characteristics of an average older adult male. Increased RCT severity was represented by systematically decreasing peak isometric muscle forces of supraspinatus, infraspinatus, and subscapularis. Five static postures in both scapular and frontal planes were evaluated. Results revealed that in both scapular and frontal planes, the peak glenohumeral joint contact force magnitude remained relatively consistent across increased RCT severity (average 1.5% and −4.2% change, respectively), and a relative balance of the transverse force couple is maintained even in massive RCT models. Predicted muscle activations of intact muscles, like teres minor, increased (average 5–30% and 4–17% in scapular and frontal planes, respectively) with greater RCT severity. This suggests that the system is prioritizing glenohumeral joint stability, even with severe RCT, and that unaffected muscles play a compensatory role to help stabilize the joint.

Recovery of Range of Motion and Decrease in Pain after Progression of Supraspinatus Tendon Tear: A Case Report

Rotator cuff disease is one of the most prevalent shoulder disabilities especially in the elderly population. Tear progression is significantly greater in the symptomatic patients than in the asymptomatic ones. From these aspects, shoulder surgeons interpret surgical indications and counsel patients regarding the risk of non-operative treatments. However, there were a few reports that pain and duration of symptoms were not strongly associated with severity of rotator cuff tears, and non-operative management with physical therapy was effective. There have remained controversies for the treatment of rotator cuff tears.A 59-year-old man with a sedentary work life experienced right shoulder pain with abduction at night. However, the pain kept worsening after two months, and he finally visited our clinic three months after the onset of pain. Magnetic resonance imaging in the coronal and axial planes showed effusion around the subacromial and subcoracoid bursae and joint-side tear of the supraspinatus tendon. A range of motion in the right shoulder was severely restricted at the initial visit of our clinic. After sufficient rehabilitation, the symptoms were not changed and an arthroscopic rotator cuff repair was scheduled. However, during waiting for surgery, he felt something popped in the right shoulder while wearing a jacket. Immediately after this, pain during motion and at night decreased, and he experienced no difficulty with activities of daily living and the surgery was cancelled. This is the first case with a recovery of range of motion and a decrease in pain after progression of a supraspinatus tendon tear.

The influence of rotator cuff tears on muscle and joint-contact loading after reverse total shoulder arthroplasty.

Rotator cuff tears are known to affect clinical outcome of reverse total shoulder arthroplasty (RSA). This study aimed to use computational modelling to quantify the effect of rotator cuff tear severity on muscle and joint forces after RSA, as well as stresses at the glenosphere, base-plate, fixation screws, scapula, and humeral components. A multi-body musculoskeletal model of the glenohumeral joint was developed comprising the scapula, humerus and nine major upper limb muscles. Simulations of abduction and flexion after RSA were performed in the case of the intact rotator cuff and tears to (i) supraspinatus; (ii) supraspinatus and infraspinatus, and (iii) supraspinatus, infraspinatus and subscapularis. The intact and supraspinatus deficient rotator cuff resulted in the largest calculated muscle forces, glenohumeral joint contact forces and implant stresses. Peak glenohumeral joint forces during flexion were lower than those during abduction in all cases; however, substantially more posterior joint shear force was generated during flexion than abduction. A tear involving the supraspinatus and infraspinatus reduced glenohumeral joint forces by a factor of 8.7 during abduction (603.1 N) and 7.1 during flexion (520.7 N) compared to those in the supraspinatus deficient shoulder. RSA with an intact or supraspinatus deficient rotator cuff produces large glenohumeral joint forces that may increase base-plate failure risk, particularly during flexion when posterior shear forces are largest. Infraspinatus tears after RSA greatly reduce glenohumeral joint compression and may ultimately reduce joint stability. Future research ought to focus on experimental validation of subject-specific muscle recruitment strategies and joint loading after RSA. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Synovial fluid biomarkers: association with chronic rotator cuff tear severity and pain

We tested the hypothesis that biomarkers in the synovial fluid of the glenohumeral (shoulder) joint are correlated with visual analog scale (VAS) scores, functional scores, and ultrasound findings of chronic rotator cuff tear (RCT) severity. We measured biomarkers in shoulder joint synovial fluid of 42 patients with partial-thickness (21), nonmassive full-thickness (10), and massive full-thickness (11) RCTs. Pain duration, tear severity, and VAS and functional scores were compared with interleukin (IL) 1β, IL-6, matrix metalloproteinase (MMP) 1, and MMP-13 levels. Both MMP-1 and MMP-13 levels were significantly highest in the massive full-thickness group. MMP-13 levels were significantly different between groups, but proinflammatory cytokine IL-1β and IL-6 levels were not. However, IL-1β levels were significantly positively correlated with VAS (r = 0.66; P <.01) and functional scores (r = 0.61; P <.01), but IL-6, MMP-1, and MMP-13 levels were not. IL-1β levels in shoulder synovial fluid correlated positively with shoulder pain and functional scores in patients with chronic RCTs. Both MMP-1 and MMP-13 levels were altered and increased with cuff tear severity.

A new scale measuring translation of the humeral head as a prognostic factor for the treatment of large and massive rotator cuff tears

Failure rates after rotator cuff repair remain high in patients with massive tears. Although superior translation of the humeral head has been used to assess the severity of rotator cuff tears, the relevance of anterior migration of the humeral head to clinical outcomes has not been established. The purpose of this study was to investigate the potential role of the T-scale, a measure of the anterolateral translation of the humeral head, as a prognostic factor for rotator cuff repair. One hundred twenty consecutive patients with full-thickness rotator cuff tears underwent primary rotator cuff repair. The T-scale and acromiohumeral interval (AHI) were measured preoperatively on axial computed tomography scans and radiographs, respectively. The correlations of the T-scale and AHI with previously published scores and active forward elevation (FE) were investigated. The outcome of rotator cuff repairs was compared between patients with positive and patients with negative preoperative T-scale values. The preoperative T-scale but not AHI correlated significantly with postoperative FE and clinical scores in patients with large to massive tears but not in those with small to medium tears. Postoperative FE and clinical scores were significantly higher in patients with positive T-scale values than in those with negative T-scale values. The relative risk of retear was 2.0 to 7.9 times greater in patients with negative T-scale values. Patients with large to massive tears and negative T-scale values had poorer clinical outcomes and higher retear rates. A negative T-scale value represents a useful prognostic factor for considering reverse shoulder arthroplasty in patients at greater risk of retear after rotator cuff repair.

Rotator cuff muscle degeneration and tear severity related to myogenic, adipogenic, and atrophy genes in human muscle.

Large rotator cuff tear size and advanced muscle degeneration can affect reparability of tears and compromise tendon healing. Clinicians often rely on direct measures of rotator cuff tear size and muscle degeneration from magnetic resonance imaging (MRI) to determine whether the rotator cuff tear is repairable. The objective of this study was to identify the relationship between gene expression changes in rotator cuff muscle degeneration to standard data available to clinicians. Radiographic assessment of preoperative rotator cuff tear severity was completed for 25 patients with varying magnitudes of rotator cuff tears. Tear width and retraction were measured using MRI, and Goutallier grade, tangent (tan) sign, and Thomazeau grade were determined. Expression of myogenic-, adipogenic-, atrophy-, and metabolism-related genes in biopsied muscles were correlated with tear width, tear retraction, Goutallier grade, tan sign, and Thomazeau grade. Tear width positively correlated with Goutallier grade in both the supraspinatus (r = 0.73) and infraspinatus (r = 0.77), along with tan sign (r = 0.71) and Thomazeau grade (r = 0.68). Decreased myogenesis (Myf5), increased adipogenesis (CEBPα, Lep, Wnt10b), and decreased metabolism (PPARα) correlated with radiographic assessments. Gene expression changes suggest that rotator cuff tears lead to a dramatic molecular response in an attempt to maintain normal muscle tissue, increase adipogenesis, and decrease metabolism. Fat accumulation and muscle atrophy appear to stem from endogenous changes rather than from changes mediated by infiltrating cells. Results suggest that chronic unloading of muscle, induced by rotator cuff tear, disrupts muscle homeostasis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2808-2814, 2017.

Reliability of MR Quantification of Rotator Cuff Muscle Fatty Degeneration Using a 2-point Dixon Technique in Comparison with the Goutallier Classification: Validation Study by Multiple Readers

Presurgical assessment of fatty degeneration is important in the management of patients with rotator cuff tears. The Goutallier classification is widely accepted as a qualitative scoring system, although it is highly observer-dependent and has poor reproducibility. The objective of this study was to quantify fatty degeneration of the supraspinatus muscle using a 2-point Dixon technique in patients with rotator cuff tears by multiple readers, and to evaluate the reproducibility compared to Goutallier classification. Two hundred patients with rotator cuff tears who underwent magnetic resonance imaging (MRI), including 2-point Dixon sequence at 3.0-T, were selected retrospectively. Qualitative and quantitative analyses of fatty degeneration were performed by two radiologists and three orthopedic surgeons independently. The fat quantification was performed by measuring signal intensity values of in phase (S(In)) and fat image (S(Fat)), and calculating fat fraction as S(Fat)/S(In). The reproducibility of MR quantification was analyzed by the intra- and interclass correlation coefficients and Bland-Altman plots. The interobserver agreement of the Goutallier classification among five readers was moderate (k = 0.51), whereas the interclass correlation coefficient regarding fat fraction value quantified in 2-point Dixon sequence was excellent (0.893). The mean differences in fat fraction values from the individual segmentation results were from -0.072 to 0.081. Proposed fat fraction grading and Goutallier grading showed similar frequency and distribution in severity of rotator cuff tears. Fat quantification in the rotator cuff muscles using a 2-point Dixon technique at 3.0-T MRI is highly reproducible and clinically feasible in comparison to the qualitative evaluation using Goutallier classification.