Mid-term outcomes following reverse total shoulder arthroplasty

The utilization of reverse total shoulder arthroplasty now exceeds the incidence of anatomic shoulder arthroplasty. Previous mid-to-long-term studies on rTSA have reported a decrease in shoulder function as follow-up increased. The purpose of this study was to provide data on mid-term outcomes and implant survival in a series focusing on reverse total shoulder arthroplasty.

Demographic information such as age at surgery, revision surgery status, BMI, and smoking status were recorded. The clinical endpoints measured in this study were range of motion scores (forward elevation, external rotation, internal rotation) and patient reported outcomes (VAS, ASES, SST). Radiographic variables captured included preoperative glenoid morphology, humeral lucency, and glenoid loosening.

Fifty-six shoulders were included in this study. The overall mean age at surgery was 72.5 ± 7.2 years with an average follow-up time of 6.8 ± 3.5 years. The mean BMI was 28.1 ± 5.5. All measurements of range of motion saw significant and sustained improvements. Overall, forward elevation improved from 82° preoperatively to 133° postoperatively (p < 0.01). External rotation improved from 23° preoperatively to 36° (p < 0.01), while internal rotation improved from L3 to L1 (p = 0.05). ASES scores improved from 31 preoperatively to 70 postoperatively (p < 0.01). SST scores improved from 2 preoperatively to 7 (p < 0.01). VAS pain index scores improved from 6 to 2 following surgery (p < 0.01). Postoperative scapular notching was seen in 18 patients at final follow-up. Glenoid loosening was seen in 3 shoulders. Humeral loosening was seen in 18 shoulders. Tuberosity resorption was seen in 8 shoulders. The 5 year survival estimate was 98%, and the 10 year survival estimate was 83%.

In this series, we found that rTSA provides mid-term improvements in range of motion in patients while reducing pain levels. When considered together, this demonstrates that most patients undergoing rTSA can have excellent use of their shoulder from age at surgery to end-of-life.