One hundred and ten patients (103 completed follow up) with developmental dysplasia of the hip and scheduled for a total hip replacement were randomized to receive a 2 week early rehabilitation program plus 2 weeks of abductor strength training (n=46) or a 2 week early rehabilitation program alone (n=57) for post-operative recovery. The outcomes of interest included range of motion, hip abductor strength, limb length discrepancy, the 10 m walk test, Harris Hip Scores (HHS), the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index, Short Form-12 (SF-12) mental and physical component scores, and the incidence of adverse events. Outcomes were assessed at 3 months and 6 months post-operation. Results demonstrated statistically significantly greater range of motion in flexion, extension, abduction and adduction in the abductor training group compared to the control group at both 3 and 6 months post-operation (p<0.05 for all). Moreover, range of motion in internal rotation and external rotation were statistically significantly in favour of the abductor training group at 6 months only (p=0.013; p=0.004, respectively). Hip abductor strength, 10 meter walk test results, HHS scores, WOMAC index scores, SF-12 physical component scores, and SF-12 mental component score were statistically significantly in favour of the abductor training group at both 3 and 6 months post-operation (p<0.05 for all). No statistical significant differences in limb length discrepancy were observed between the two groups at either time point. No cases of trochanteric non-union or sciatic palsy were observed in either group.