Shoulder arthroplasty following gastric bypass, do complications follow?

INTRODUCTION: Previous reports have shown an increased risk of complications after arthroplasty in the obese population. It remains unclear if gastric bypass surgery prior to shoulder arthroplasty modifies the complication and failure rate. The purpose of this study is to assess the complication and re-operation rates following shoulder arthroplasty in this population.

METHODS: Between 2002 and 2012, 39 shoulders with prior gastric bypass underwent shoulder arthroplasty (3 HA, 16 TSA, 20 RSA). The mean time from the gastric bypass to arthroplasty was 13 years (range, 0.7-32). Shoulders were followed for a minimum of two years (mean, 3.8 years) or until re-operation. Outcome measures included pain, range of motion, satisfaction, modified Neer ratings, and ASES scores.

RESULTS: Complications occurred in seven shoulders (18%), with five requiring re-operation. There was no common failure mechanism. Re-operations occurred for aseptic glenoid loosening, periprosthetic fracture, and unexplained pain. Those shoulders with complications were similar to those without in regard to age, sex, and BMI. Complications were more common following anatomic arthroplasty compared to reverse arthroplasty (5 vs 1, p = 0.06); however, complications were not improved compared to historical controls with morbid obesity. Overall, pain improved significantly from 4.8 pre-operatively to 2.3 postoperatively (p < 0.001). All groups, regardless of arthroplasty type, demonstrated significant improvements in forward elevation and external rotation.

CONCLUSION: Gastric bypass surgery prior to shoulder arthroplasty leads to clinical improvement in both pain and range of motion. Prior gastric bypass surgery does not result in a lower surgical complication rate compared to previously published reports in the morbidly obese population.

LEVEL OF EVIDENCE: Level 4, case series.