The long-term outcome after varus derotational osteotomy for Legg-Calvé-Perthes disease: A mean follow-up of 42 years

Background: Varus derotational osteotomy (VDRO) is one of the most common surgical treatments for Legg-Calvé- Perthes disease, yet its long-term results have not been fully assessed. We aimed to determine the long-term clinical and radiographic outcomes following VDRO. Methods: Forty patients (43 hips) who underwent VDRO for Legg-Calvé-Perthes disease at our institution from 1959 to 1983, and participated in a follow-up study completed 10 years earlier, were approached for the present study. Clinical examination and radiographs were evaluated. Hip status and well-being were assessed with theHarris hip score and the Short Form-36 (SF-36). Results: Thirty-five patients (37 hips) participated in the study. Information regarding the need for an arthroplasty was gathered on 4 additional hips from the previous study. The mean follow-up was 42.5 years (range, 32.4 to 56.5 years), with a mean patient age of 50.2 years (range, 35.9 to 67.8 years). In total, 7 patients (7 hips; 17% of 41 hips for which information was available, including 1 hip from the original cohort of 40 patients [43 hips]), underwent a total hip arthroplasty for hip pain. Excluding patients who had undergone an arthroplasty, the mean Harris hip and SF-36 scores were 79.8 points (range, 23.1 to 100 points) and 74.8 (range, 15.1 to 100), respectively. Twenty (64.5%) of the 31 hips that had not been replaced achieved a good or excellent Harris hip score (≥80 points). Sixteen (57.1%) of 28 hips with follow-up radiographs had no, or minimal, signs of osteoarthritis. The Stulberg classification was associated with the Harris hip score, the SF-36 score, hip pain, a Trendelenburg sign, coxa magna, and the Tönnis grade. In a multivariate analysis, the Stulberg classification was the only factor associated with fair or poor outcomes (a Harris hip score of <80 points). Patients with a Stulberg class-III or IV hip had significant deterioration with respect to the Harris hip score and Tönnis grade during the 10-year period since the last follow-up. Conclusions: A long-term follow-up of patients who were operatively treated for Legg-Calvé-Perthes disease revealed that a low proportion underwent total hip arthroplasty and a relatively high proportion maintained good clinical and radiographic outcomes. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.