Propensity Score-Matched Comparison of Patient-Reported Outcomes Between Crowe I Developmental Dysplasia of the Hip and Primary Osteoarthritis Following Total Hip Arthroplasty.

Abstract

Total hip arthroplasty (THA) is commonly performed for Crowe I developmental dysplasia of the hip (DDH) and primary osteoarthritis (OA), but comparative survivorship and patient-reported outcome measure (PROM) data remain limited with mixed findings. This study aimed to compare PROMs, revision rates, and implant survivorship between propensity-matched THA patients who had Crowe I DDH and OA. A retrospective review of a single surgeon's case log was performed to identify patients who had a diagnosis of DDH or OA who underwent THA. Propensity-score matching was utilized, yielding 105 DDH hips and 105 OA hips. Primary outcomes were modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score - Joint Replacement (HOOS-JR), Visual Analog Scale (VAS) for pain, and University of California, Los Angeles Activity Scale (UCLA) collected preoperatively, at one year, and at minimum 2-year final follow-up. The secondary outcomes included implant survivorship via Kaplan-Meier analysis, multivariable logistic regression for minimal clinically important difference (MCID) and substantial clinical benefit (SCB) achievement, revision rates, and radiographic assessment of leg length discrepancy and acetabular inclination. There were no significant between-group differences in any PROM at any time point (all P > 0.05). Analysis of covariance (ANCOVA) confirmed equivalent adjusted final scores across all four PROMs (all P > 0.14). MCID was achieved in over 92% of both cohorts for mHHS, HOOS-JR, and VAS. There were four revisions in the DDH group (three instability, one periprosthetic joint infection) and three in the OA group; revision rates did not differ significantly (P = 1.0). Kaplan-Meier survivorship analysis showed no significant difference between groups (log-rank P = 0.83). In this propensity-matched series, Crowe I DDH and OA patients achieved comparable midterm PROMs, revision rates, and implant survivorship after THA. Furthermore, preoperative functional status, rather than underlying diagnosis, was the primary predictor of achieving minimal clinically important difference (MCID). These findings suggest that contemporary THA provides similar clinical benefits across both diagnoses.