Functional Improvement and Patient Satisfaction Following Conversion of Fused Hip to Total Hip Arthroplasty

This study aimed to determine the clinical outcomes, predictors of suboptimal functional improvement, and factors influencing patient satisfaction following conversion of a fused hip to total hip arthroplasty (THA).

A retrospective analysis of clinical and radiographic data was performed on 83 patients (83 hips) who underwent fused hip conversion to THA. Implant survival and predictors of poor functional outcome (Harris hip score < 70) were analyzed. In addition, factors associated with patient dissatisfaction (visual analog scale < 25th percentile) were analyzed in 63 patients (63 hips) who completed a patient-reported outcome measures questionnaire.

The median Harris hip score improved from 55 (range, 18 to 77) to 78 (range, 36 to 100) at a mean follow-up of 10.2 ± 4.8 years (P < .001). Implant survival was 97.4% at 10 years and 91.3% at 20 years, with any revision as the endpoint. Multivariate analysis identified preoperative reliance on mobility aids as an independent predictor of poor functional outcome (P = .021). There were 48 of 63 patients (76%) satisfied (satisfaction visual analog scale ≥80) with the operated hip. Demographics and preoperative/postoperative clinical data did not differ between satisfied and unsatisfied patients. Among the patient-reported outcome measures, the Forgotten Joint Score-12 emerged as an independent discriminator of patient satisfaction.

Conversion of a fused hip to THA provides functional improvement, favorable implant survival, and high patient satisfaction. However, patients dependent on mobility aids may experience suboptimal functional recovery, underscoring the need for careful preoperative counseling and patient selection.