Achievement of primary stability using 3D-CT guided custom design femoral stems in patients with proximal femoral deformity : EBRA-FCA analysis

Abstract

Hip replacement in patients with proximal femoral deformity and end stage arthrosis is technically challenging. The purpose of this study was to measure the subsidence rate of custom femoral stems using EBRA-Femoral Component Analysis (FCA) software, as an indicator of achievement of primary stability. We retrospectively reviewed 14 hips in 12 consecutive patients who underwent this procedure between June 2008 and Feb. 2011. There were 7 males and 5 females with a mean age 41 years (22-60). The primary diagnosis in the majority of the cases was Perthes and DDH with secondary osteoarthritis. The average follow up period was 36 ± 10 months (19-51 months). Average subsidence was the 0.96 mm ± 0.95mm (0- 2.9 mm). All patients had signs of osteointegration at the metaphyseal level. We conclude that the 3D-CT guided custom made femoral stem produces reliable proximal ‘fit and fill' and osteointegration without the need of a corrective osteotomy in patients with proximal femoral deformity but long term studies are needed to assess the performance of this femoral stem.