Cementless Total Hip Arthroplasty With a High Hip Center for Hartofilakidis Type B Developmental Dysplasia of the Hip: Results of Midterm Follow-Up.

Abstract

Acetabular reconstruction in adults with Hartofilakidis type B developmental dysplasia of the hip is a major technical challenge. The purpose of this retrospective study was to evaluate hip function and radiographic outcomes regarding high hip center at midterm follow-up. From January 1, 2007 to December 31, 2009, 37 patients who had Hartofilakidis type B developmental dysplasia of the hip underwent a primary total hip arthroplasty using a high hip center technique. Functional, radiographic, and survivorship outcomes were evaluated. Of the 37 patients, 31 patients (83.8%) were available for the mean follow-up of 6.1 years (range, 1.5-7.6 years). Thirty-one cementless cups were located at an average vertical distance of 38.1 ± 3.3 mm and at a mean horizontal distance of 35.5 ± 3.4 mm. The mean ratio of the height of the hip center was 2.4% (range, 2.0%-2.9%). The Harris Hip Scores were improved from 50.3 points (range, 38-63 points) preoperatively to 92.3 points (range, 85-100 points) at the final follow-up (P < .001). Four patients continued to present with Trendelenburg gait pattern at the last follow-up. With use of revision for any reason and aseptic loosening as the end point, the 5-year survival rates were 90.3% (95% CI, 79.9%-100%) and 93.3% (95% CI, 84.3%-100%), respectively. The high hip center technique in conjunction with a cementless acetabular component seems to be a valuable alternative to achieve satisfactory midterm outcomes for Hartofilakidis type B developmental dysplasia of the hip.