Revisions for aseptic glenoid component loosening after anatomic shoulder arthroplasty.

BACKGROUND: Glenoid component loosening is a common indication for revision shoulder arthroplasty. The objective of this study is to assess the longer-term outcomes of patients undergoing revision specifically for aseptic loosening.

MATERIALS AND METHODS: Between 1985 and 2005, 34 revision shoulder arthroplasties were performed for aseptic glenoid loosening. Three patients were lost to follow-up. Treatment included component reimplantation in 20 shoulders (group I) or component removal with bone grafting in 11 shoulders (group II). We identified 9 cases of instability with or without rotator cuff tearing prior to revision. The mean follow-up period was 8.3 years.

RESULTS: The rate of survival free of reoperation at 10 years was 78.9% in group I and 83.9% in group II (P = .5). Pain relief occurred in 26 of 31 shoulders, with no difference between groups (P > .99). Active elevation and external rotation improved in both groups (P = .8). Five shoulders in group I had radiographically loose glenoids, with two requiring reoperation. Nine shoulders in group II had medial glenoid erosion, with two requiring reoperation for pain. There was a trend toward reoperation in those with preoperative instability (5 of 8 re-revisions).

DISCUSSION AND CONCLUSION: Glenoid revision surgery in the absence of infection provides satisfactory results, especially when instability is not coexisting. When glenoid bone stock permits, reimplantation of a new glenoid component in an active patient with an intact rotator cuff and no instability is reasonable. When the remaining glenoid bone will not support a new component, conversion to a hemiarthroplasty is also reasonable.