Early outcomes of shoulder arthroplasty according to sex

Abstract

Hypothesis

Among patients undergoing shoulder arthroplasty (SA), female patients would have worse outcomes than their male counterparts.

Methods

A multicenter prospective cohort of 2364 patients (1365 female and 999 male patients) treated with total SA or reverse total SA from 2007 to 2015 was retrospectively analyzed. Results were assessed using several validated outcome measures and range-of-motion testing. A multivariable analysis identified differences in preoperative values, postoperative values, and preoperative-to-postoperative improvements while adjusting for possible confounders.

Results

The mean follow-up period was 45.9 ± 23.7 months in female patients and 46.4 ± 23.6 months in male patients. Women underwent SA at a significantly older age (70.8 ± 8.4 years) than men (67.6 ± 8.8 years, P < .01) and began with lower preoperative outcome scores and range-of-motion measurements: American Shoulder and Elbow Surgeons score ( P < .01), Constant score ( P < .01), Simple Shoulder Test score ( P < .01), active abduction ( P < .01), forward flexion ( P < .01), and external rotation ( P = .02). Postoperatively, both groups showed significant improvement. When we evaluated overall improvement from preoperative values, female patients showed increased improvements in the American Shoulder and Elbow Surgeons score ( P = .04) and Simple Shoulder Test score ( P < .01), as well as active forward elevation ( P < .01) and external rotation ( P = .02). However, the difference in improvements did not reach the minimal clinically important difference. Women had a higher incidence of component loosening ( P = .03) and periprosthetic fractures due to falls ( P = .01), whereas men showed a higher incidence of periprosthetic joint infections ( P < .01).

Conclusion

This study found that female patients undergo SA at an older age and begin with worse shoulder range of motion and outcome scores than male patients. Although women experienced a greater improvement postoperatively in outcome scores and range of motion, this improvement did not reach the minimal clinically important difference. These findings suggest that male and female patients can expect similar improvements in function after undergoing SA; however, the incidence of complications may vary depending on sex.