Factors Associated With Humeral Avulsion of Glenohumeral Ligament Lesions in Patients With Anterior Shoulder Instability: An Analysis of the MOON Shoulder Instability Cohort.

Background: Humeral avulsion of the glenohumeral ligament (HAGL) lesions are an uncommon cause of anterior glenohumeral instability and may occur in isolation or combination with other pathologies. As HAGL lesions are difficult to detect via magnetic resonance imaging (MRI) and arthroscopy, they can remain unrecognized and result in continued glenohumeral instability. Purpose: To compare patients with anterior shoulder instability from a large multicenter cohort with and without a diagnosis of a HAGL lesion and identify preoperative physical examination findings, patient-reported outcomes, imaging findings, and surgical management trends associated with HAGL lesions. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients with anterior glenohumeral instability who underwent surgical management between 2012 and 2020 at 11 orthopaedic centers were enrolled. Patients with HAGL lesions identified intraoperatively were compared with patients without HAGL lesions. Preoperative characteristics, physical examinations, imaging findings, intraoperative findings, and surgical procedures were collected. The Student t test, Kruskal-Wallis H test, Fisher exact test, and chi-square test were used to compare groups. Results: A total of 21 HAGL lesions were identified in 915 (2.3%) patients; approximately one-third (28.6%) of all lesions were visualized intraoperatively but not identified on preoperative MRI. Baseline characteristics did not differ between study cohorts. Compared with non-HAGL patients, HAGL patients were less likely to have a Hill-Sachs lesion (54.7% vs 28.6%; P = .03) or an anterior labral tear (87.2% vs 66.7%; P = .01) on preoperative MRI and demonstrated increased external rotation when their affected arm was positioned at 90° of abduction (85° vs 90°; P = .03). Additionally, HAGL lesions were independently associated with an increased risk of undergoing an open stabilization surgery (odds ratio, 74.6 [95% CI, 25.2-221.1]; P < .001). Conclusion: Approximately one-third of HAGL lesions were missed on preoperative MRI. HAGL patients were less likely to exhibit preoperative imaging findings associated with anterior shoulder instability, such as Hill-Sachs lesions or anterior labral pathology. These patients underwent open procedures more frequently than patients without HAGL lesions.

A Microcurrent Dressing Reduces Cutibacterium Acnes Colonization in Patients Undergoing Shoulder Arthroplasty or Arthroscopy: A Prospective Case Series.

Background: Cutibacterium acnes infections in the shoulder remain a significant concern in the setting of shoulder arthroplasty. Purpose: We sought to evaluate the efficacy of a microcurrent dressing in reducing C. acnes skin colonization and thereby reducing the risk of periprosthetic joint infection of the shoulder. Methods: This study was designed as a prospective case series. From October 2017 to February 2019, patients undergoing elective shoulder arthroplasty or arthroscopic shoulder surgery at a major academic medical center were offered enrollment; they signed an informed consent to participate. Patients under the age of 18, scheduled for revision shoulder arthroplasty, or with sensitivity or allergy to silver, zinc, or latex were excluded. Subjects underwent skin culture swab of the shoulder in the mid-point of the planned deltopectoral incision. The JumpStart (Arthrex; Naples, FL) microcurrent dressing was then placed over the area of the planned incision, and a full-thickness skin biopsy was harvested from the incision at the initiation of the surgical procedure. All specimens were cultured for C. acnes by the hospital's clinical microbiology laboratory with standard anaerobic technique. Results: Thirty-one subjects were enrolled in the study. Those who demonstrated no growth at baseline for the control specimen were excluded from further analysis (N = 11), given the absence of preoperative C. acnes colonization. Culture results from the 20 remaining subjects revealed significantly diminished C. acnes skin growth at the time of surgery compared to baseline. Sixty percent (12 of 20) of the subjects with positive skin swabs at baseline demonstrated no growth in the skin biopsy specimens at the time of surgery. There were no adverse events associated with the application of the microcurrent dressing. Conclusion: This prospective case series found that preoperative application of a microcurrent dressing resulted in significantly diminished C. acnes skin burden at the time of surgery in patients undergoing elective shoulder arthroplasty or arthroscopic shoulder surgery. Further study is warranted to investigate whether this preoperative intervention may contribute to a reduction in perioperative infections, including prosthetic joint infection.

Treatment of Massive Rotator Cuff Tears with Reverse Shoulder Arthroplasty.

Most massive rotator cuff tears (MCTs) are often successfully treated with nonoperative treatment; however, various surgical treatment options are available if conservative management fails. Several joint preserving techniques for MCT are commonly used, but the options are limited if an MCT is irreparable. Reverse total shoulder arthroplasty (RTSA) is gaining popularity over hemiarthroplasty as a treatment option for irreparable MCT, especially if glenohumeral degenerative changes are present. RTSA has been shown to have improved functional outcomes and range of motion postoperatively, particularly in the elderly and patients with pseudoparalysis.

Patient reported outcomes and ranges of motion after reverse total shoulder arthroplasty with and without subscapularis repair.

Background: In performing reverse total shoulder arthroplasty (rTSA), the role of repairing the subscapularis has been debated. Our objective was to determine the effect of subscapularis repair following rTSA on postoperative shoulder ranges of motion and patient reported outcome scores (PROs). Methods: A prospective registry was reviewed to establish a cohort of primary rTSA patients with a 135-degree humeral implant, with a minimum of 2 years of follow-up. Variables collected included demographics, subscapularis repair information, diagnosis, glenosphere size, and glenoid lateralization information. Outcomes collected were range of motion measurements, subscapularis strength, and multiple generic and shoulder PROs. Multivariable linear regression models were created to predict these 2-year outcomes. Results: The 143-patient cohort had a mean age of 69 years with 68% of patients undergoing subscapularis repair. After adjustment in the multivariable models, whether the subscapularis was repaired did not significantly predict a 2-year forward elevation, external rotation, internal rotation, subscapularis strength, Western Ontario Osteoarthritis of the Shoulder score, VR-12 scores, Constant Score, or American Shoulder and Elbow Surgeons Shoulder Scores. Increased glenoid lateralization significantly predicted greater internal rotation, higher VR-12 physical score, and higher Constant Score. There were no dislocations in either group. Conclusions: After adjusting for patient and implant factors, subscapularis repair was not associated with a 2-year postoperative range of motion, strength, or any PROs suggesting that repairing the subscapularis may not affect functional outcome. Increased glenoid lateralization through the baseplate and glenosphere independently predicted better internal rotation, VR-12 physical score, and Constant Scores indicating a benefit to lateralization during rTSA.

Beach Chair Versus Lateral Decubitus Position: Differences in Suture Anchor Position and Number During Arthroscopic Anterior Shoulder Stabilization.

BACKGROUND: Arthroscopic shoulder capsulolabral repair using glenoid-based suture anchor fixation provides consistently favorable outcomes for patients with anterior glenohumeral instability. To optimize outcomes, inferior anchor position, especially at the 6-o'clock position, has been emphasized. Proponents of both the beach-chair (BC) and lateral decubitus (LD) positions advocate that this anchor location can be consistently achieved in both positions. HYPOTHESIS: Patient positioning would be associated with the surgeon-reported labral tear length, total number of anchors used, number of anchors in the inferior glenoid, and placement of an anchor at the 6-o'clock position. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: This study was a cross-sectional analysis of a prospective multicenter cohort of patients undergoing primary arthroscopic anterior capsulolabral repair. Patient positioning in the BC versus LD position was determined by the operating surgeon and was not randomized. At the time of operative intervention, surgeon-reported labral tear length, total anchor number, anchor number in the inferior glenoid, and anchor placement at the 6-o'clock position were evaluated between BC and LD cohorts. Descriptive statistics and between-group differences (continuous: t test [normal distributions], Wilcoxon rank sum test [nonnormal distributions], and chi-square test [categorical]) were assessed. RESULTS: In total, 714 patients underwent arthroscopic anterior capsulolabral repair (BC vs LD, 406 [56.9%] vs 308 [43.1%]). The surgeon-reported labral tear length was greater for patients having surgery in the LD position (BC vs LD [mean ± SD], 123.5°± 49° vs 132.3°± 44°; P = .012). The LD position was associated with more anchors placed in the inferior glenoid and more frequent placement of anchors at the 6-o'clock (BC vs LD, 22.4% vs 51.6%; P < .001). The LD position was more frequently associated with utilization of ≥4 total anchors (BC vs LD, 33.5% vs 46.1%; P < .001). CONCLUSION: Surgeons utilizing the LD position for arthroscopic capsulolabral repair in patients with anterior shoulder instability more frequently placed anchors in the inferior glenoid and at the 6-o'clock position. Additionally, surgeon-reported labral tear length was longer when utilizing the LD position. These results suggest that patient positioning may influence the total number of anchors used, the number of anchors used in the inferior glenoid, and the frequency of anchor placement at the 6 o'clock position during arthroscopic capsulolabral repair for anterior shoulder instability. How these findings affect clinical outcomes warrants further study. REGISTRATION: NCT02075775 (ClinicalTrials.gov identifier).

Subscapularis-sparing approaches in shoulder arthroplasty: A systematic review.

BACKGROUND: Novel approaches for anatomic and reverse total shoulder arthroplasty (aTSA and rTSA) that spare the subscapularis (SSC) have recently been described. Outcomes for the SSC-sparing approach were evaluated through this systematic review. METHODS: Medline, Embase, PubMed, and CENTRAL were searched. RESULTS: From 2051 citations, 8 studies were included (aTSA group, n = 241; rTSA group, n = 68). SSC-sparing aTSA and rTSA were associated with significant postoperative improvements in shoulder function and range of motion at 12- to 24-month follow-up. CONCLUSION: The SSC-sparing approach may provide a safe alternative for up to two years post-surgery. Evidence for long-term use remains inconclusive.

Male Sex, Western Ontario Shoulder Instability Index Score, and Sport as Predictors of Large Labral Tears of the Shoulder: A Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability Cohort Study.

PURPOSE: To identify factors predictive of a large labral tear at the time of shoulder instability surgery. METHODS: As part of the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort, patients undergoing open or arthroscopic shoulder instability surgery for a labral tear were evaluated. Patients with >270° tears were defined as having large labral tears. To build a predictive logistic regression model for large tears, the Feasible Solutions Algorithm was used to add significant interaction effects. RESULTS: After applying exclusion criteria, 1235 patients were available for analysis. There were 222 females (18.0%) and 1013 males (82.0%) in the cohort, with an average age of 24.7 years (range 12 to 66). The prevalence of large tears was 4.6% (n = 57), with the average tear size being 141.9°. Males accounted for significantly more of the large tears seen in the cohort (94.7%, P = .01). Racquet sports (P = .01), swimming (P = .02), softball (P = .05), skiing (P = .04), and golf (P = .04) were all associated with large labral tears, as was a higher Western Ontario Shoulder Instability Index (WOSI; P = .01). Age, race, history of dislocation, and injury during sport were not associated with having a larger tear. Using our predictive logistic regression model for large tears, patients with a larger body mass index (BMI) who played contact sports were also more likely to have large tears (P = .007). CONCLUSIONS: Multiple factors were identified as being associated with large labral tears at the time of surgery, including male sex, preoperative WOSI score, and participation in certain sports including racquet sports, softball, skiing, swimming, and golf. LEVEL OF EVIDENCE: I, prognostic study.

Risk Factors for Intra-articular Bone and Cartilage Lesions in Patients Undergoing Surgical Treatment for Posterior Instability.

BACKGROUND: Patients with posterior shoulder instability may have bone and cartilage lesions (BCLs) in addition to capsulolabral injuries, although the risk factors for these intra-articular lesions are unclear. HYPOTHESIS: We hypothesized that patients with posterior instability who had a greater number of instability events would have a higher rate of BCLs compared with patients who had fewer instability episodes. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Data from the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Group instability patient cohort were analyzed. Patients aged 12 to 99 years undergoing primary surgical treatment for shoulder instability were included. The glenohumeral joint was evaluated by the treating surgeon at the time of surgery, and patients were classified as having a BCL if they had any grade 3 or 4 glenoid or humeral cartilage lesion, reverse Hill-Sachs lesion, bony Bankart lesion, or glenoid bone loss. The effects of the number of instability events on the presence of BCLs was investigated by use of Fisher exact tests. Logistic regression modeling was performed to investigate the independent contributions of demographic variables and injury-specific variables to the likelihood of having a BCL. Significance was defined as P < .05. RESULTS: We identified 271 patients (223 male) for analysis. Bone and cartilage lesions were identified in 54 patients (19.9%) at the time of surgical treatment. A glenoid cartilage injury was most common and was identified in 28 patients (10.3%). A significant difference was noted between the number of instability events and the presence of BCLs (P = .025), with the highest rate observed in patients with 2 to 5 instability events (32.3%). Multivariate logistic regression modeling indicated that increasing age (P = .019) and 2 to 5 reported instability events (P = .001) were significant independent predictors of the presence of BCLs. For bone lesions alone, the number of instability events was the only significant independent predictor; increased risk of bone lesion was present for patients with 1 instability event (OR, 6.1; P = .012), patients with 2 to 5 instability events (OR, 4.2; P = .033), and patients with more than 5 instability events (OR, 6.0; P = .011). CONCLUSION: Bone and cartilage lesions are seen significantly more frequently with increasing patient age and in patients with 2 to 5 instability events. Early surgical stabilization for posterior instability may be considered to potentially limit the extent of associated intra-articular injury. The group of patients with more than 5 instability events may represent a different pathological condition, as this group showed a decrease in the likelihood of cartilage injury, although not bony injury.

The Prevalence and Clinical Implications of Comorbid Back Pain in Shoulder Instability: A Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability Cohort Study.

BACKGROUND: Understanding predictors of pain is critical, as recent literature shows that comorbid back pain is an independent risk factor for worse functional and patient-reported outcomes (PROs) as well as increased opioid dependence after total joint arthroplasty. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate whether comorbid back pain would be predictive of pain or self-reported instability symptoms at the time of stabilization surgery. We hypothesized that comorbid back pain will correlate with increased pain at the time of surgery as well as with worse scores on shoulder-related PRO measures. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: As part of the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort, patients consented to participate in pre- and intraoperative data collection. Demographic characteristics, injury history, preoperative PRO scores, and radiologic and intraoperative findings were recorded for patients undergoing surgical shoulder stabilization. Patients were also asked, whether they had any back pain. RESULTS: The study cohort consisted of 1001 patients (81% male; mean age, 24.1 years). Patients with comorbid back pain (158 patients; 15.8%) were significantly older (28.1 vs 23.4 years; P < .001) and were more likely to be female (25.3% vs 17.4%; P = .02) but did not differ in terms of either preoperative imaging or intraoperative findings. Patients with self-reported back pain had significantly worse preoperative pain and shoulder-related PRO scores (American Shoulder and Elbow Surgeons score, Western Ontario Shoulder Instability Index) (P < .001), more frequent depression (22.2% vs 8.3%; P < .001), poorer mental health status (worse scores for the RAND 36-Item Health Survey Mental Component Score, Iowa Quick Screen, and Personality Assessment Screener) (P < .01), and worse preoperative expectations (P < .01). CONCLUSION: Despite having similar physical findings, patients with comorbid back pain had more severe preoperative pain and self-reported symptoms of instability as well as more frequent depression and lower mental health scores. The combination of disproportionate shoulder pain, comorbid back pain and mental health conditions, and inferior preoperative expectations may affect not only the patient's preoperative state but also postoperative pain control and/or postoperative outcomes.

Surgical Versus Nonsurgical Management of Rotator Cuff Tears: A Matched-Pair Analysis.

BACKGROUND: Rotator cuff disease is a major medical and economic burden due to a growing aging population, but management of rotator cuff tears remains controversial. We hypothesized that there is no difference in outcomes between patients who undergo rotator cuff repair and matched patients treated nonoperatively. METHODS: After institutional review board approval, a prospective cohort of patients over 18 years of age who had a full-thickness rotator cuff tear seen on magnetic resonance imaging (MRI) were retrospectively evaluated. After clinical evaluation, each patient elected to undergo either rotator cuff repair or nonsurgical treatment. Demographic information was collected at enrollment, and self-reported outcome measures (the Normalized Western Ontario Rotator Cuff Index [WORCnorm], American Shoulder and Elbow Surgeons score [ASES], Single Assessment Numerical Evaluation [SANE], and pain score on a visual analog scale [VAS]) were collected at baseline and at 6, 12, and >24 months. The Functional Comorbidity Index (FCI) was used to assess health status at enrollment. The size and degree of atrophy of the rotator cuff tear were classified on MRI. Propensity score analysis was used to create rotator cuff repair and nonsurgical groups matched by age, sex, symptom duration, FCI, tear size, injury mechanism, and atrophy. The Student t test, chi-square test, and regression analysis were used to compare the treatment groups. RESULTS: One hundred and seven patients in each group were available for analysis after propensity score matching. There were no differences between the groups with regard to demographics or rotator cuff tear characteristics. For all outcome measures at the time of final follow-up, the rotator cuff repair group had significantly better outcomes than the nonsurgical treatment group (p < 0.001). At the time of final follow-up, the mean outcome scores (and 95% confidence interval) for the surgical repair and nonsurgical treatment groups were, respectively, 81.4 (76.9, 85.9) and 68.8 (63.7, 74.0) for the WORCnorm, 86.1 (82.4, 90.3) and 76.2 (72.4, 80.9) for the ASES, 77.5 (70.6, 82.5) and 66.9 (61.0, 72.2) for the SANE, and 14.4 (10.2, 20.2) and 27.8 (22.5, 33.5) for the pain VAS. In the longitudinal regression analysis, better outcomes were independently associated with younger age, shorter symptom duration, and rotator cuff repair. CONCLUSIONS: Patients with a full-thickness rotator cuff tear reported improvement in pain and functional outcome scores with nonoperative treatment or surgical repair. However, patients who were offered and chose rotator cuff repair reported greater improvement in outcome scores and reduced pain compared with those who chose nonoperative treatment. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Clinical Outcomes After Anterior Shoulder Stabilization in Overhead Athletes: An Analysis of the MOON Shoulder Instability Consortium.

BACKGROUND: Traumatic anterior shoulder instability is a common condition affecting sports participation among young athletes. Clinical outcomes after surgical management may vary according to patient activity level and sport involvement. Overhead athletes may experience a higher rate of recurrent instability and difficulty returning to sport postoperatively with limited previous literature to guide treatment. PURPOSE: To report the clinical outcomes of patients undergoing primary arthroscopic anterior shoulder stabilization within the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability Consortium and to identify prognostic factors associated with successful return to sport at 2 years postoperatively. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Overhead athletes undergoing primary arthroscopic anterior shoulder stabilization as part of the MOON Shoulder Instability Consortium were identified for analysis. Primary outcomes included the rate of recurrent instability, defined as any patient reporting recurrent dislocation or reoperation attributed to persistent instability, and return to sport at 2 years postoperatively. Secondary outcomes included the Western Ontario Shoulder Instability Index and Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow questionnaire score. Univariate regression analysis was performed to identify patient and surgical factors predictive of return to sport at short-term follow-up. RESULTS: A total of 49 athletes were identified for inclusion. At 2-year follow-up, 31 (63%) athletes reported returning to sport. Of those returning to sport, 22 athletes (45% of the study population) were able to return to their previous levels of competition (nonrefereed, refereed, or professional) in at least 1 overhead sport. Two patients (4.1%) underwent revision stabilization, although 14 (28.6%) reported subjective apprehension or looseness. Age ( P = .87), sex ( P = .82), and baseline level of competition ( P = .37) were not predictive of return to sport. No difference in range of motion in all planes ( P > .05) and Western Ontario Shoulder Instability Index scores (78.0 vs 80.1, P = .73) was noted between those who reported returning to sport and those who did not. CONCLUSION: Primary arthroscopic anterior shoulder stabilization in overhead athletes is associated with a low rate of recurrent stabilization surgery. Return to overhead athletics at short-term follow-up is lower than that previously reported for the general athletic population.

Impact of smoking on patient outcomes after arthroscopic rotator cuff repair.

BACKGROUND: Cigarette smoking may adversely affect rotator cuff tear pathogenesis and healing. However, the impact of cigarette smoking on outcomes after arthroscopic rotator cuff repair is relatively unknown. PATIENTS AND METHODS: A cohort of 126 patients who underwent arthroscopic rotator cuff repair with minimum 2 years follow-up were retrospectively identified from our institutional database. Patient demographics, comorbidities, and cuff tear index were collected at initial presentation. Outcome measures including American Shoulder and Elbow Surgeons (ASES) score, Western Ontario Rotator Cuff (WORC) score and Visual Analogue Scale (VAS) for pain were collected at each clinical follow-up. Mixed model regression analysis was used to determine the impact of smoking on outcomes, while controlling for tear size and demographics. RESULTS: In our cohort, 14% were active or recent smokers. At baseline, smokers presented with higher pain, greater comorbidities and worse ASES scores than non-smokers. Smokers also had a non-significant trend towards presenting for surgical repair at a younger age and with larger tear sizes. Both smokers and non-smokers had statistical improvements in outcomes at 2 years following repair. Regression analysis revealed that smokers had a worse improvement in ASES but not WORC or VAS pain scores after surgery. CONCLUSION: The minimal clinically important difference was achieved for ASES, WORC and VAS pain in both smokers and non-smokers, suggesting both groups substantially benefit from arthroscopic rotator cuff repair. Smokers tend to present with larger tears and worse initial outcome scores, and they have a lower functional improvement in response to surgery.

Establishing Minimal Important Differences for the VR-12 and SANE Scores in Patients Following Treatment of Rotator Cuff Tears.

BACKGROUND: Minimal important differences (MIDs) for the Veterans RAND 12-Item Health Survey (VR-12) and the Single Assessment Numeric Evaluation (SANE) have not been reported in patients following treatment for rotator cuff tears (RCTs). PURPOSE: To determine the MIDs for the VR-12 and SANE among patients with RCT after treatment. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHOD: A total of 222 patients diagnosed with RCT completed the VR-12 and SANE at baseline and then received surgical or nonsurgical treatment. After 64 weeks, 160 patients completed the VR-12, the SANE, and a global change questionnaire. We applied a distribution-based approach to estimate the MIDs for the SANE and for the physical component score (PCS) and mental component score (MCS) of the VR-12. We then used the global rating score as an anchor for 20 patients who perceived a minimal improvement, and we applied an anchor-based approach. One-half standard deviation of the baseline score was used in the distribution-based approach. Linear regression analyses and backward model selection were conducted to evaluate the associations between patients' characteristics and the anchor-based MIDs. RESULTS: The MIDs derived from distribution-based method estimates for the VR-12 PCS, MCS, and SANE scores were 4.94, 5.99, and 11.80, respectively. The MIDs estimated using the anchor-based method for the PCS, MCS, and SANE scores were 2.57 (90% CI, -1.62 to 6.76), 1.87 (90% CI, -2.07 to 5.80), and 27.25 (90% CI, 16.17 to 38.33), respectively. The final regression model for significant predictors of the MID on the PCS included baseline PCS (P < .001), body mass index (P = .014), symptom duration (P = .011), diabetes (P = .009), and surgery (P = .089). The final model for the MID on the MCS included baseline MCS (P < .001), patient sex (P = .027), and diabetes (P = .083). The final model for the MID on SANE included baseline SANE score (P = .059) and diabetes (P = .050). CONCLUSION: This is the first study to assess the MIDs for the VR-12 and SANE scores in patients with rotator cuff disease. The estimates of MID will facilitate the interpretation and application of these outcome measures in clinical practice and research.

Multimodality Imaging Review of Normal Appearance and Complications of the Postoperative Rotator Cuff.

OBJECTIVE: The objective of this article is to provide a multimodality imaging review of the imaging features of the postoperative rotator cuff, including a discussion of the most common complications. CONCLUSION: Both MRI and ultrasound can be used to evaluate the repaired rotator cuff and potential complications. The appearance of the rotator cuff within the first 6 months after repair is heterogeneous and may be difficult to interpret but normalizes over time.

Descriptive Epidemiology of the MOON Shoulder Instability Cohort.

BACKGROUND: Shoulder instability is a common diagnosis among patients undergoing shoulder surgery. PURPOSE: To perform a descriptive analysis of patients undergoing surgery for shoulder instability through a large multicenter consortium. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients undergoing surgery for shoulder instability who were enrolled in the MOON Shoulder Instability Study were included. Baseline demographics included age, sex, body mass index, and race. Baseline patient-reported outcomes (PROs) included the American Shoulder and Elbow Surgeons (ASES) score, Shoulder Activity Score, Western Ontario Shoulder Instability Index (WOSI), 36-Item Health Survey (RAND-36), and Single Assessment Numeric Evaluation (SANE). The preoperative physician examination included active range of motion (ROM) and strength testing. Preoperative imaging assessments with plain radiography, magnetic resonance imaging (MRI), and computed tomography were also included and analyzed. RESULTS: Twenty-six surgeons had enrolled 863 patients (709 male, 154 female) across 10 clinical sites. The mean age for the cohort was 24 years (range, 12-63 years). Male patients represented 82% of the cohort. The primary direction of instability was anterior for both male (74%) and female (73%) patients. Football (24%) and basketball (13%) were the most common sports in which the primary shoulder injury occurred. No clinically significant differences were found in preoperative ROM between the affected and unaffected sides for any measurement taken. Preoperative MRI scans were obtained in 798 patients (92%). An anterior labral tear was the most common injury found on preoperative MRI, seen in 66% of patients, followed by a Hill-Sachs lesion in 41%. Poor PRO scores were recorded preoperatively (mean: ASES, 72.4; WOSI, 43.3; SANE, 46.6). CONCLUSION: The MOON Shoulder Instability Study has enrolled the largest cohort of patients undergoing shoulder stabilization to date. Anterior instability is most common among shoulder instability patients, and most patients undergoing shoulder stabilization are in their early 20s or younger. The results of this study provide important epidemiological information for patients undergoing shoulder stabilization surgery.

Establishing minimally important differences for the American Shoulder and Elbow Surgeons score and the Western Ontario Rotator Cuff Index in patients with full-thickness rotator cuff tears.

BACKGROUND: The American Shoulder and Elbow Surgeons (ASES) score and the Western Ontario Rotator Cuff Index (WORC) are frequently used measures in clinical research for patients with rotator cuff tears (RCTs). The minimally important differences (MIDs) for these measures have not been established in patients with RCTs. The purpose of this study was to establish the MIDs for patients with known RCTs treated both surgically or nonsurgically. METHODS: We included 222 subjects with full-thickness RCTs. The WORC and ASES were collected at baseline and at 4, 8, 16, 32, 48, and 64 weeks, as was an end of study form with questions about change in the condition after treatment. We calculated anchor-based and distribution-based MIDs. We used regression modeling to determine change in MIDs as predicted by several variables. RESULTS: For the anchor-based method, we found an MID of 21.9 for the ASES and -282.6 for the WORC. When using the distribution-based method of ½ and ⅓ the standard deviation, we arrived at an MID of 26.9 and 17.9 points for the ASES and -588.7 and -392.5 points for the WORC. No variables predicted MID changes. CONCLUSION: This is the first study to report MIDs for the ASES and WORC in a population of patients with only full-thickness RCTs. This information will directly improve our ability to determine when patients with RCTs are changing in a meaningful manner and accurately power clinical studies using these outcome measures.

Does Increased Body Mass Index Influence Outcomes After Rotator Cuff Repair?

PURPOSE: To investigate the influence of pre-existing obesity (body mass index [BMI] ≥ 30) on outcomes after rotator cuff repair surgery. METHODS: We collected data on adult patients who underwent surgical repair for symptomatic full-thickness rotator cuff tears confirmed by imaging between 2012 and 2015. The required follow-up was 3 years. At baseline and 6, 12, 24, and 36 months, the American Shoulder and Elbow Surgeons score, Western Ontario Rotator Cuff index, and visual analog scale pain scores were collected. Complications were assessed by a chart review. Obesity was defined as BMI ≥ 30. Chi-square analysis and Student's t-test examined differences between categorical and continuous variables at baseline. Generalized estimating equations examined the effects of fixed factors on outcome variables longitudinally from baseline to 36 months. RESULTS: Thirty-nine percent of 213 subjects were obese (mean BMI = 29.2; range, 16-48; standard deviation, 5.8). There were no statistically significant differences between obese and nonobese subjects in other baseline characteristics. When controlling for covariates, obese subjects reported no differences in Western Ontario Rotator Cuff, American Shoulder and Elbow Surgeons, or visual analog scale pain scores when compared with nonobese subjects at baseline and over 3 years from surgery. Although obese patients were more likely to have inpatient surgery, there was no difference in the incidence of postoperative complications. CONCLUSIONS: Contrary to our hypothesis, obese participants who underwent rotator cuff repair reported no difference in functional outcome or pain scores compared with nonobese participants over 3 years. In addition, obesity was not associated with postoperative complications in this study. However, as we hypothesized, obese participants were more likely than nonobese participants to have repair in the inpatient setting. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Platform shoulder arthroplasty: a systematic review.

BACKGROUND: Platform shoulder arthroplasty systems may allow conversion to a reverse total shoulder arthroplasty (RTSA) without removing a well-fixed, well-positioned humeral stem. We sought to evaluate the complications associated with humeral stem exchange versus retention in patients undergoing conversion shoulder arthroplasty with a platform shoulder arthroplasty system. METHODS: PubMed, MEDLINE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Embase were searched from database inception through October 9, 2016, for all articles comparing humeral stem retention versus exchange during conversion RTSA or that pertained to conversion RTSA with stem retention alone. All studies were screened in duplicate for eligibility. A methodologic quality assessment was completed for included studies. Pooled outcomes assessing complications, operative time, blood loss, and reoperations were determined. RESULTS: We included 7 studies (236 shoulders), including 1 level III and 6 level IV studies. Pooled analysis demonstrated significantly higher overall complications (odds ratio, 6.89; 95% confidence interval [CI], 2.48-19.13; P = .0002), fractures (odds ratio, 4.62; 95% CI, 1.14-18.67; P = .03), operative time (mean difference, 62.09 minutes; 95% CI, 51.17-73.01 minutes; P < .00001), and blood loss (mean difference, 260.06 mL; 95% CI, 165.30-354.83 mL; P < .00001) with humeral stem exchange. Stem exchange was also associated with increased risk of reoperation (P = .0437). CONCLUSION: Conversion arthroplasty with retention of the humeral stem is associated with lower overall complications, blood loss, operative time, and reoperations in comparison with stem exchange.

Do Medical Comorbidities Affect Outcomes in Patients With Rotator Cuff Tears?

BACKGROUND: The effects of medical comorbidities on clinical outcomes in patients with rotator cuff tears (RCTs) have not been fully elucidated. This study investigates the association between medical comorbidities, as measured by the Functional Comorbidity Index (FCI), and clinical outcomes in patients treated surgically or nonsurgically for symptomatic, full-thickness RCTs. HYPOTHESIS: Patients with RCTs who have more comorbidities will have worse outcome scores. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We collected the following outcome measures at baseline and at regular intervals up to 64 weeks in all patients: FCI, the Western Ontario Rotator Cuff Index (WORC), and the American Shoulder and Elbow Surgeons (ASES) score. Changes in outcomes were compared separately for surgical and nonsurgical patients using paired t tests. The relationship of the FCI and all outcomes of interest at baseline, at 64-week follow-up, and for changes from baseline was explored using linear regression modeling. RESULTS: Of the 222 study patients (133 males; mean age, 60.0 ± 9.6 years), 140 completed the 64-week WORC and 120 completed the 64-week ASES. Overall, 128 patients underwent RCT repair, and 94 patients were treated nonsurgically. Both treatment groups improved compared with baseline at 64 weeks on the ASES score and WORC. At 64 weeks, patients with higher baseline FCI scores had worse WORC score (by 74.5 points; P = .025) and ASES score (by 3.8 points; P < .01). A higher FCI score showed a trend toward predicting changes in the WORC and ASES scores at 64 weeks compared with baseline, but this did not reach statistical significance (WORC change, P = .15; ASES change, P = .07). CONCLUSION: Patients with higher FCI scores at baseline reported worse baseline functional scores and demonstrated less improvement with time. The magnitude of this change may not be clinically significant for single comorbidities.

Tranexamic Acid in Shoulder Arthroplasty: A Systematic Review and Meta-Analysis.

BACKGROUND: The role of tranexamic acid (TXA) in reducing blood loss following primary shoulder arthroplasty has been demonstrated in small retrospective and controlled clinical trials. This study comprehensively evaluates current literature on the efficacy of TXA to reduce perioperative blood loss and transfusion requirements following shoulder arthroplasty. METHODS: PubMed, MEDLINE, CENTRAL, and Embase were searched from the database inception date through October 27, 2016, for all articles evaluating TXA in shoulder arthroplasty. Two reviewers independently screened articles for eligibility and extracted data for analysis. A methodological quality assessment was completed for all included studies, including assessment of the risk of bias and strength of evidence. The primary outcome was change in hemoglobin and the secondary outcomes were drain output, transfusion requirements, and complications. Pooled outcomes assessing changes in hemoglobin, drain output, and transfusion requirements were determined. RESULTS: Five articles (n = 629 patients), including 3 Level-I and 2 Level-III studies, were included. Pooled analysis demonstrated a significant reduction in hemoglobin change (mean difference [MD], -0.64 g/dL; 95% confidence interval [CI], -0.84 to -0.44 g/dL; p < 0.00001) and drain output (MD, -116.80 mL; 95% CI, -139.20 to -94.40 mL; p < 0.00001) with TXA compared with controls. TXA was associated with a point estimate of the treatment effect suggesting lower transfusion requirements (55% lower risk); however, the wide CI rendered this effect statistically nonsignificant (risk ratio, 0.45; 95% CI, 0.18 to 1.09; p = 0.08). Findings were robust with sensitivity analysis of pooled outcomes from only Level-I studies. CONCLUSIONS: Moderate-strength evidence supports use of TXA for decreasing blood loss in primary shoulder arthroplasty. Further research is necessary to evaluate the efficacy of TXA in revision shoulder arthroplasty and to identify the optimal dosing and route of administration of TXA in shoulder arthroplasty. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.