Although the indications for anatomic and reverse total shoulder arthroplasty (TSA) are different, better understanding of the rate of improvement with each type of surgery could help establish more realistic patient expectations for recovery—and help surgeons and physical therapists design different strategies for postoperative care. With those goals in mind, Simovitch et al. use prospectively collected data to compare, at a minimum 2-year follow-up, clinical and range-of-motion (ROM) outcomes among 505 anatomic TSA patients and 678 reverse TSA patients. The findings appear in in the November 1, 2017 issue of JBJS.
The authors tracked five clinical outcome scores (SST, UCLA Shoulder, ASES, Constant, and SPADI), along with 4 relevant ROM measures. In both groups, >95% of patients reported clinical improvement in all 5 clinical metrics by 6 months, and full improvement was noted by 24 months. Not surprisingly, the mean age of patients who underwent reverse TSA was >5 years older and their shoulder-function scores and ROM were generally worse than those of the anatomic TSA patients.
At the time of the latest follow-up, patients who underwent anatomic TSA fared significantly better than patients who underwent reverse TSA in 3 of the 5 clinical outcome metrics and in all 4 ROM measurements. On the other hand, those who had reverse TSAs had significantly larger improvements in the Constant score (which emphasizes strength more than the other 4 clinical metrics) and active forward flexion.
ROM-wise, at approximately 6 years after surgery, the authors noted a progressive decrease in the magnitude of improvement for abduction and forward flexion in both groups. According to Simovitch et al., the observed discrepancies between clinical and ROM outcomes at longer-term follow-up suggest that “subjective (e.g., patient-reported) assessments of outcome and function likely continue to be stable or improve despite range-of-motion worsening and, as such, may imply that patient expectations change with follow-up time.”