Revision total hip arthroplasty for large medial defects with witch's hat-shaped structural allografts - minimum 10-year follow-up

A witch's hat-shaped structural allograft can restore bone stock over acetabular medial wall during revision total hip arthroplasty, which may be of importance for future re-revisions. However, long-term results are unclear. A retrospective review of 104 consecutive hips in 96 patients was performed to determine survivorship and functions. The minimum follow-up was 10. years. Nine patients required re-revision for cup aseptic loosening with a mean time to revision of 4.5. years. Kaplan-Meier survivorship was 89.4% at the endpoint. Radiographic evaluation revealed sixteen instances of minor medial wall graft absorption without significant cup migration. The mean modified Harris Hip Scores were 36 preoperatively and 86 at last follow-up. Revision acetabular surgery using a witch's hat-shaped allograft to restore acetabular medial wall provides an excellent alternative.