Effects of age and body mass index on the results of transtrochanteric rotational osteotomy for XXXX : surgical technique.

@entity1 @entity571 @entity39 @entity5 @entity5040 @entity572 @entity2738 @entity2530
BACKGROUND: @entity5 and a large area of necrotic bone are known risk factors for failure of transtrochanteric rotational osteotomy of the hip in @entity1 with @entity2530 . The purpose of this study was to determine whether there are other risk factors for failure of this osteotomy. METHODS: One hundred and five @entity1 (113 @entity572 ) underwent an anterior transtrochanteric rotational osteotomy for the treatment of @entity2738 and were followed for a mean of 51.3 months postoperatively. Radiographic failure was defined as secondary collapse or osteoarthritic change. Multivariate analysis was performed to assess factors associated with secondary collapse and @entity5040 formation. The Kaplan-Meier product-limit method was used to estimate survival. RESULTS: Secondary collapse occurred in twenty-seven @entity572 (24%), and fourteen @entity572 (12%) were converted to a total hip arthroplasty. At the time of the most recent follow-up, the hip scores according to the system of Merle d'Aubign   et al. ranged from 6 to 18 points (mean, 15.8 points). Multivariate analysis showed that the stage of the @entity39 (III or greater) (hazard ratio = 3.28; 95% confidence interval = 1.49 to 7.24), age of the @entity1 (forty years or older) (hazard ratio = 1.08; 95% confidence interval = 1.02 to 1.14), body mass index (>= 24 kg/m(2)) (hazard ratio = 1.19; 95% confidence interval = 1.03 to 1.38), and extent of the @entity39 (a combined necrotic angle of >= 230  ) (hazard ratio = 1.08; 95% confidence interval = 1.04 to 1.11) were associated with secondary collapse. Seven of the eighty-six @entity572 without collapse showed progression to @entity571 . The survival rate at 110 months was 63.4% (95% confidence interval = 51.1% to 75.7%) with total hip arthroplasty or radiographic failure as the end point and 56.0% (95% confidence interval = 44.6% to 67.4%) with total hip arthroplasty, radiographic failure, or loss to follow-up as the end point. CONCLUSIONS: Our study showed that age, body mass index, and the stage and extent of the @entity2530 were determining factors for secondary collapse, unsatisfactory clinical results, and conversion to total hip arthroplasty. These factors should be considered when selecting @entity1 for a transtrochanteric rotational osteotomy.
