A 58-year-old man from Mumbai with a 5-year history of osteoarthritis of the right hip presents with progressive pain in the groin and medial thigh, worse on internal rotation and abduction. He has a positive FABER test and FADIR test. Plain radiographs show joint space narrowing, osteophytes, and mild acetabular dysplasia. His pain is now affecting his gait and limiting activities of daily living despite 6 months of NSAIDs, physiotherapy, and one intra-articular corticosteroid injection 3 months ago. What is the most appropriate next step in management?