Patient-Reported Outcome Measures After Direct Anterior Total Hip Arthroplasty Are Comparable Between Patients With Developmental Dysplasia of the Hip and Osteoarthritis: A Propensity-Matched Analysis.

Abstract

Degenerative changes secondary to hip dysplasia may be treated with total hip arthroplasty (THA) through a direct anterior approach. However, this may be challenging due to altered pathoanatomy and difficult visualization of the femur. The purpose of this study was to compare patient-reported outcome measures between patients with hip dysplasia and matched controls with osteoarthritis who underwent direct anterior THA. Patients who underwent direct anterior THA were retrospectively reviewed. Dysplastic hips were propensity matched to hips with osteoarthritis on a 1:4 basis. Patient-reported outcome measures, including visual analog scale pain at rest and with use, Hip Disability and Osteoarthritis Outcome Score Pain, and Forgotten Joint Score-12, were obtained at follow-up. In addition, modified Harris Hip scores (mHHS) were obtained both preoperatively and at the final follow-up. Thirty-eight hips with dysplasia and 152 control hips were followed for a mean of 5.1 ± 2.8 years. Eighty-seven percent of the dysplastic hips had Grade I hip dysplasia based on the Crowe classification, whereas 5.3% had Grade II, 2.6% had Grade III, and 5.3% had Grade IV. Both cohorts demonstrated notable preoperative to postoperative improvements in mHHS (P < 0.001). No differences were observed at the final follow-up between the dysplasia and osteoarthritis cohorts for VAS at rest (0.5 vs. 0.5, P = 0.828), visual analog scale with use (0.7 vs. 1.1, P = 0.231), Hip Disability and Osteoarthritis Outcome Score Pain (93.8 vs. 92.3, P = 0.518), Forgotten Joint Score-12 (82.2 vs. 81.4, P = 0.856), and mHHS (91.9 vs. 91.4, P = 0.793). Revision rates were comparable between the dysplasia and osteoarthritis cohorts (5.3% vs. 1.3%, P = 0.179). Patients with hip dysplasia and osteoarthritis who underwent direct anterior THA achieved comparable outcomes in this propensity-matched analysis. Patients with hip dysplasia can expect reduced pain, improved functional outcomes, and similar revision surgery rates to those with osteoarthritis following primary THA.