How Is Maximum Outcome Improvement Defined in Patients Undergoing Shoulder Arthroscopy for Rotator Cuff Repair? A 1-Year Follow-Up Study

Abstract

Purpose: To (1) determine the American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), and Constant-Murley subjective score thresholds for achieving maximal outcome improvement (MOI) after arthroscopic rotator cuff repair and (2) identify preoperative predictors of reaching the ASES threshold for achieving MOI.

Methods: A retrospective cohort study was performed to identify patients undergoing rotator cuff repair at a high-volume institution from January 2014 to January 2017 with a 1-year minimum follow-up. Patient characteristics, as well as preoperative and postoperative outcome scores, were analyzed. MOI for the ASES and SANE score were calculated as previously described, and a receiver operating characteristic (ROC) curve analysis was used to determine thresholds for percentage of maximal improvements for each outcome measure based on a satisfaction anchor question. Last, a logistic regression model was used to identify predictors of reaching the ASES threshold for achieving MOI.

Results: A total of 220 patients were included in the final analysis. There was a statistically significant increase in score average across all 3 outcome measures (P < .001 for all), with 162 (73.6%) patients rating their surgical outcome as satisfactory at 1-year follow-up. The ROC curve analysis demonstrated that ASES, SANE, and Constant-Murley threshold percentages for achieving MOI was 69.5% (area under the curve [AUC], 0.86; 95% confidence interval [CI], 0.81-0.91; P < .001), 75% (AUC, 0.814; 95% CI, 0.758-0.871; P < .001), and 55.1% (AUC, 0.84; 95% CI, 0.783-0.898; P < .001), respectively. Logistic regression demonstrated that workers compensation cases (odds ratio, 0.69; 95% CI, 0.55-0.86; P = .001) and dominant-sided surgery (odds ratio, 0.72; 95% CI, 0.59-0.88; P = .002) were predictors of not achieving maximal improvement on the ASES score.

Conclusion: Achieving 69.5% of maximal ASES score improvement or 75% of maximal SANE score improvement is indicative of achieving patient satisfaction after arthroscopic rotator cuff repair. Preoperative variables including workers compensation cases and surgery to the dominant side were predictors of not achieving maximal improvement.

Level of evidence: IV, case series.