Early clinical and radiological outcomes of reverse shoulder arthroplasty with an eccentric all-polyethylene glenosphere to treat failed hemiarthroplasty and the sequelae of proximal humeral fractures

Purpose

The aim of this study was to assess the effectiveness of reverse total shoulder arthroplasty (RTSA) with an all-polyethylene glenosphere in patients with failed hemiarthroplasty (HH) or the sequelae of proximal humeral fractures.

Methods

Thirty-six patients were assessed at a mean follow-up of 36 months using clinical scores and recording shoulder range of movement (ROM).

Results

Active anterior elevation (p < 0.001), lateral elevation (p < 0.001) and internal rotation (p < 0.0001) improved significantly, whereas improvement in external rotation was not significant. The mean Constant score rose significantly from 8.5 ± 7.6 to 40.7 ± 15.7 (p < 0.001) and the Simple Shoulder Test score from 0.42 ± 0.85 to 5.5 ± 2.6 (p < 0.001). Pain improved significantly from 8.7 ± 0.9 to 2.3 ± 1.2 (p < 0.001). Implant radiographic survivorship was 84.6 %. Scapular notching was detected in 7/36 patients (17.5 %). There were five complications: one (stiffness) among patients with fracture sequelae and four among those with failed HH (instability, n = 2; humeral component disassembly, n = 1; pain, n = 1). The two groups did not exhibit significant differences in pain, clinical scores or ROM.

Discussion

RTSA with an all-polyethylene glenosphere may have the potential to reduce the risk of biological notching due to polyethylene osteolysis. Further long-term studies are required to assess its efficacy.

Conclusions

The good clinical performance and reasonable rate of notching of the polyethylene glenosphere support its use in primary and revision shoulder arthroplasty.

Level of evidence: Level 4, retrospective therapeutic case series.