Impaction bone grafting for femoral revision hip arthroplasty with Exeter stem in Japan: An extended 10-to 15-year stem survival analysis of the previously reported series

Background: Femoral impaction bone grafting (IBG) was introduced in the late 1990s in Japan and has gradually become recognized as a useful option for femoral revision. The aim of the present study was to retrospectively analyze 10 to 15 years of clinical results of femoral revision arthroplasties of IBG using Exeter stem performed by experienced Japanese surgeons. Methods: We investigated radiographic and clinical records more than 2 years after surgery in 99 hips of 93 patients. The average age was 66.3 years (36-84 years) and the average follow-up period was 11 years (2 -23 years and 8 months). Merle d'Aubigne = and Postel hip score was used for clinical assessment, and reoperations for any reason were recorded. The survival curve was estimated using Kaplan-Meier method. Results: The mean Merle d'Aubigne = and Postel hip score improved from 9.0 points to 14.5 points at the final follow-up. Re-operations were undertaken in 15 hips of 14 patients for aseptic acetabular component loosening (n = 1 hip), recurrent dislocation (n = 2 hips), infection (n = 4 hips), and periprosthetic femoral fracture (n = 8 hips). The survival rates at 10 and 15 years after operation were 87.1% and 81.1% with any type of re-operation as the endpoint, 92.2% and 92.2% with stem removal or exchange as the endpoint, 94.9% and 88.1% with re-operation for periprosthetic femoral fracture as the endpoint, and 99.0% and 99.0% with re-operation for aseptic stem loosening as the endpoint, respectively. Conclusions: The present study showed encouraging results of femoral IBG over 10 years by experienced surgeons in Japan. Although femoral IBG is recognized as a technically complex procedure, survivorship of the stem is excellent, with a 15-year stem survival rate of 99.0% at the end point of aseptic loosening. (c) 2022 The Authors. Published by Elsevier B.V. on behalf of The Japanese Orthopaedic Association. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).