Comparison of Total Hip Arthroplasty Outcomes after Failed Femoral Wedge or Curved Varus Osteotomy

BACKGROUND: Differences in clinical and radiographic results following total hip arthroplasty between failed wedge and curved varus osteotomy are unclear. OBJECTIVE: To investigate differences in clinical and radiographic results following total hip arthroplasty in patients who exhibited failed wedge or curved varus osteotomy. METHOD: We performed 18 total hip arthroplasties after failed femoral varus osteotomy. Hips were divided into two groups: 14 had failed wedge varus osteotomy and four had failed curved varus osteotomy. Average ages at osteotomy and total hip arthroplasty were 27 years old (range, 10-46 years old) and 56 years old (range, 25-74 years old), respectively. The average duration of follow-up monitoring was 72.2 months (range, 54-91 months). Clinical and radiographic evaluations were completed for each group. RESULTS: The Japanese Orthopaedic Association hip score of total hip arthroplasty after failed varus osteotomy significantly improved at the last follow-up in both groups. However, hip score at the last follow-up was significantly higher after failed curved varus osteotomy than after failed wedge varus osteotomy (p<0.01). Four hips that failed wedge varus osteotomy underwent subtrochanteric corrective osteotomy with total hip arthroplasty. Radiographic evaluation showed that three stems for total hip arthroplasty after failed wedge varus osteotomy were inserted in malposition, and all stems in total hip arthroplasty after failed curved varus osteotomy were inserted in the normal position. CONCLUSION: Surgeons performing femoral varus osteotomy should consider possible future conversion to total hip arthroplasty. Curved varus osteotomy is more suitable than wedge varus osteotomy for future conversion to total hip arthroplasty.