Impaction grafting of the acetabulum with ceramic bone graft substitute mixed with femoral head allograft: High survivorship in 43 patients with a median follow-up of 7 years: A follow-up report

BACKGROUND AND PURPOSE: Restoration of bone stock at revision hip surgery remains a challenge. Alternative graft materials with suitable mechanical properties for impaction grafting have been sought due to issues with infection, antigenicity, cost, and availability of allograft. We have previously presented good short-term results of the use of BoneSave, a biphasic porous ceramic bone graft substitute, consisting of sintered 80% tricalcium phosphate and 20% hydroxyapatite, in a 50:50 mix with femoral head allograft. We now present the medium-term results. METHODS: We conducted a retrospective review of a cohort of 43 consecutive patients undergoing impaction grafting of contained acetabular defects by multiple surgeons at a single center. 34 patients received uncemented acetabular components and 9 received cemented components. Patients were followed up radiographically and with the self-reported satisfaction scale (SAPS), Oxford hip score (OHS), and the Short-Form 12 (SF12) health survey. Kaplan-Meier survivorship analysis was performed with revision of the acetabular component, revision of any part of the construct, and reoperation as endpoints. RESULTS: The fate of all cases was known. Median follow-up of the surviving patients was 80 (69–106) months. 15 patients died during the follow-up period, 14 with their construct in situ. The survivorship of the grafted acetabulum and acetabular component was 94% (95% CI: 99–78) at 7 years. 1 patient had been revised for aseptic loosening of the acetabulum and 1 for deep infection. The mean OHS was 31 (SD 12), the mean SF12 physical-component score (PCS) was 38 (SD 13), the median SAPS was 83 (0–100), and the median SF12 mental-component score (MCS) was 55 (23–65). The graft material became incorporated in all 3 zones of the acetabulum in 23 out of 24 cases that had complete radiographic follow-up. INTERPRETATION: These medium-term results show that BoneSave is a reliable material for impaction grafting of the acetabulum when used in conjunction with femoral head allograft.