Total Hip Arthroplasty with Modular Stem for Dysplastic Hips in South Asian Population

Optimum component positioning and orientation is required to optimize the functional result during totalhip arthroplasty for dysplastic hips. Sixty-two patients (66 hips) including 33 males and 29 females underwent total hip arthroplasty usingmodular stem prosthesis at an average age of 40.6 years (range 17 to 49 years). Nineteen hips were classifiedas Type I, 24 hips as Type II, 13 hips as Type III and 10 hips as Type IV dysplastic hips according to Crowe’sclassification. Eighteen hips (27.2%) underwent sub trochanteric osteotomy and 23 hips (34.8%) required adductortenotomy at the time of surgery. Sixty-one patients (65 hips) were available for the latest follow up. The median follow-up was 57.4 months(range12 to 100 months). The mean Harris Hip Score was 90.6 (range 72 to 96), which was significant improvementfrom the preoperative Score of 44.8 (range 38 to 62). The clinical outcome was graded as excellent in 39, good in13, fair in 7 patients and poor in 2 patients respectively. Only one hip (1.5%) had underwent revision surgery forthe stem at 18 months following the index surgery. Postoperative dislocation following a fall was seen in one hipof a female patient who was operated on both sides. The radiographs revealed that all the remaining 65 hips hadstable femoral component and the osteotomy sites were healed. The Kaplan-Meier survivorship with revision asendpoint (including open reduction for dislocation) was found to be 96.4% at 100 months (95% Confidence Interval;86.3-99.1). This study in South-Asian patients using the modular stem strengthened the premise that cementlessmodular total hip arthroplasty provides a satisfactory outcome in treating secondary osteoarthritis due to dysplastichips.Level of evidence: IV