Do patients with poor early clinical outcomes after reverse total shoulder arthroplasty ultimately improve?

Although most patients undergoing reverse total shoulder arthroplasty (rTSA) have substantial improvement in pain and function at early follow-up, improvements in pain and range of motion progress more slowly during postoperative rehabilitation in a subset of patients. The purpose of this study was to define a patient's risk of persistent shoulder dysfunction beyond the early postoperative period and identify risk factors for persistent poor performance.

We retrospectively reviewed 292 primary rTSAs with early poor performance and a preoperative diagnosis of osteoarthritis, cuff tear arthropathy, or rotator cuff tear from a multicenter database. Early poor performance was defined as a postoperative American Shoulder and Elbow Surgeons (ASES) score below the 20th percentile at 3 months (58 points) or 6 months (65 points) postoperatively. Persistent poor performance at 2 years was defined as failure to achieve the patient acceptable symptomatic state for rTSA (77.3 points for the ASES score). The primary outcome was the rate of persistent poor performance. Secondarily, we compared the clinical outcomes of persistent poor performers vs. shoulders that improved at 2-year follow-up and assessed risk factors for persistent poor performance.

At 2-year follow-up, 61% of patients (n = 178) with poor performance at either 3- or 6-month follow-up had persistent poor performance. The rate increased to 85% if poor performance occurred at both 3- and 6-month follow-up. The minimal clinically important difference and substantial clinical benefit for range of motion and outcome scores were exceeded by early poor performers at rates of 83%-92% and 60%-77%, respectively, at 2-year follow-up. On multivariate logistic regression analysis, independent predictors of persistent poor performance after rTSA were lack of hypertension (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.13-0.57; P < .001), heart disease (OR, 2.89; 95% CI, 1.24-6.77; P = .011), uncemented humeral fixation (OR, 0.11; 95% CI, 0.01-1.18; P = .037), previous shoulder surgery (OR, 2.14; 95% CI, 1.06-4.30; P = .031), lower preoperative ASES score (OR, 0.92; 95% CI, 0.87-0.97; P = .002), and lower preoperative subjective rating of pain at its worst (OR, 0.73; 95% CI, 0.54-0.99; P = .038).

Despite the fact that 85% of rTSA patients with an ASES score below the 20th percentile at early follow-up exceeded the minimal clinically important difference for improvement in the ASES score at 2-year clinical follow-up, 61% still had persistent poor performance, with failure to achieve the patient acceptable symptomatic state for the ASES score. Persistent poor performance after rTSA was best predicted by a history of shoulder surgery and a poorer preoperative ASES score. These findings can aid surgeons when counseling patients both preoperatively and postoperatively. In the setting of early poor performance, the risk of persistent poor performance must be balanced against the potential outcomes of revision surgery when considering early surgical intervention.