Clinical outcome and repair integrity after arthroscopic rotator cuff repair significantly improved during the surgeon's learning curve.

Abstract

Whether learning curve could affect the surgical outcome after arthroscopic rotator cuff repair is still unknown. The purpose of this study was to evaluate surgical learning curve for clinical outcome and retear rate after arthroscopic rotator cuff repairs that were performed by the beginner shoulder surgeon. We hypothesized that clinical outcome and retear rate would improve over time with the accumulation of a surgeon's experience. This retrospective study consisted of 200 consecutive patients who had arthroscopic rotator cuff repairs, performed by a single surgeon between 2011 and 2018. We included symptomatic rotator cuff tears involving the supraspinatus/infraspinatus and/or subscapularis tendon and follow-up magnetic resonance imaging evaluations of repair integrity 6 months after surgery. Surgeon's learning was evaluated with calculation of cumulative retear rate and cumulative summation (CUSUM) analysis. Clinical outcomes and the retear rates were compared between group A (the first-half 100 patients) and group B (the latter-half of 100 patients). The mean follow-up period was 21 months (range, 12-55). The overall retear rate was 13% (26 patients). The CUSUM analysis showed that after patient number 97, the curve was maintained below the level of acceptable failure rate, suggesting the competency was obtained consistently. Comparing between groups, retear rate showed significant decrease from 18% in group A to 8% in group B (P = .036). Notably, retear rate in small to medium-sized tears (<3 cm) significantly decreased from 26% (12 of 46 patients) in group A to 2% (1 of 49 patients) in group B (P = .001). However, analysis in large to massive tears (≥3 cm) failed to show difference between groups (30%, 6 of 20, in group A and 25%, 6 of 24, in group B; P = .711). In multivariate analysis, higher fatty infiltration of the supraspinatus muscle (P = .008), more severe muscle atrophy of the teres minor (P = .010), and belonging to group A (P = .011) were associated with retear. Clinical outcomes and retear rate after arthroscopic rotator cuff repairs significantly improved during the learning curve period of a beginner shoulder surgeon.