Can customised total hip arthroplasty without femoral shortening osteotomy improve functional outcome and long-term stem survivorship in developmental dysplasia of the hip?

Abstract

Aims: Total hip arthroplasty (THA) combined with a shortening osteotomy of the femur has proved to be an effective treatment for patients with developmental dysplasia of the hip (DDH). Advances in surgical technique and implant design have led to the introduction of customised THA, without the inconvenience of femoral shortening osteotomy, as an alternative option.The purpose of this retrospective study was to determine if customised THA without femoral shortening osteotomy improves the functional outcome and long-term survivorship in total hip arthroplasty for DDH.

Methods: We carried out a retrospective analysis of 77 hips in 62 patients with DDH of all Crowe types who had been treated by customised THA without shortening osteotomy and who had a minimum of 20 years follow-up. Clinical evaluation was undertaken using the Harris Hip Score (HHS) at 6 weeks postoperatively and at final follow-up. Kaplan-Meier survivorship analysis was carried out with femoral revision due to aseptic loosening as the endpoint.

Results: The average HHS score at the 6 weeks postoperative assessment (86 ± 13) showed a significant improvement from the preoperative assessment (49 ± 22 points) as did the final follow-up examination (82 ± 12). The mean postoperative leg-length discrepancy was 7 ± 11 mm (-20-80 mm). 5 transient (6%) nerve palsies (1 sciatic and 4 femoral) were identified. The stem was revised in 12 hips (16%), 9(12%) for aseptic loosening at 4, 16, 70, 96, 165, 176, 177, 191 and 235 months, 2 (3%) for fracture and 1 (1%) for late infection.The Kaplan-Meier survivorship analysis at 20-year follow-up was 88% (95% confidence interval [0.81-0.96]). 7 patients (9 hips) were lost to follow-up (12%). 10 patients (11 hips) died during the study period (14%) but according to their general physician, none had undergone revision hip surgery.

Conclusions: Customised THA with 3-dimensional planning and a custom-made femoral stem may improve functional outcomes and long-term survivorship after THA for DDH.

Keywords: Aseptic loosening; custom-made stem; total hip arthroplasty.