Long-Term Outcomes of Total Hip Arthroplasty with Subtrochanteric Osteotomy for Crowe IV Dysplasia.

Background: Cementless total hip arthroplasty (THA) with subtrochanteric shortening osteotomy (SSO) is a well-established treatment for Crowe IV developmental dysplasia of the hip (DDH). However, series to date are limited by mid-term follow-up. The purpose of this study was to evaluate the long-term (mean 18 years) implant survivorship, radiographic results, and clinical outcomes of our previously published series.

Methods: We retrospectively reviewed 28 hips (24 patients) that underwent cementless THA with SSO for Crowe IV DDH between 1992 and 2005 using our institutional total joint registry. The mean age at the time of THA was 48 years, 83% were women, and the mean BMI was 27. Since the original study, five patients died, including a patient who had bilateral THAs; five hips were revised; two withdrew from the study; and one was lost to follow-up. As such, 14 hips were available for follow-up at a mean of 18 years (range, 12 to 28). Kaplan-Meier survivorship curves were calculated, radiographs were reviewed, and clinical outcomes were evaluated via the Harris Hip Score (HHS).

Results: The 20-year survivorship free of any revision was 79%. There were five revisions, including two for aseptic loosening of the femoral stem at 10 months and two years, one for stem fracture at two years, one for aseptic loosening of the acetabular component at one year, and one for polyethylene liner dissociation at six years. There were no new revisions or reoperations after six years. All unrevised hips were radiographically well-fixed at the most recent follow-up. The mean HHS was 81 at a mean of 15 years.

Conclusions: Cementless THA with SSO for Crowe IV DDH provides good implant survivorship with durable fixation and reliable clinical outcomes at long-term (mean 18 years) follow-up. In this series, femoral aseptic loosening was rare. Methods: Therapeutic level IV.