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?

Explanation

## Surgical Intervention in Hip Osteoarthritis ### Clinical Assessment This patient has: - **Established primary hip OA** with radiological confirmation (joint space narrowing, osteophytes) - **Underlying acetabular dysplasia** — a risk factor for early-onset OA - **Failed conservative management** — 6 months of NSAIDs + physiotherapy + one intra-articular corticosteroid injection - **Significant functional impairment** — affecting gait and ADLs - **Positive provocative tests** (FABER, FADIR) — consistent with intra-articular hip pathology ### Why Total Hip Arthroplasty? **Key Point:** Total hip arthroplasty (THA) is indicated when symptomatic OA fails conservative and injectable medical management and causes significant functional impairment affecting quality of life. **High-Yield:** Criteria for THA in OA: 1. Radiologically confirmed OA (Kellgren-Lawrence Grade 3–4) 2. Failed conservative therapy (NSAIDs, physiotherapy) for ≥6 months 3. Failed intra-articular injection (1–2 attempts) 4. Significant functional limitation (pain at rest, night pain, gait disturbance) 5. Patient age and comorbidities permitting surgery **Clinical Pearl:** Hip OA with underlying dysplasia (as in this case) tends to progress more rapidly and respond less favorably to conservative management. Early THA may be justified to prevent further cartilage destruction and preserve bone stock. ### Comparison of Options | Intervention | Indication | Timing | Evidence | |---|---|---|---| | **Total hip arthroplasty** | Failed conservative + injectable therapy, severe functional impairment | Now | Gold standard; 90% pain relief, 15–20 year durability | | Repeat corticosteroid injection | Partial response, mild-moderate OA | Not indicated (already failed) | Diminishing returns after 1–2 injections | | Hyaluronic acid | NSAID intolerance, mild OA | Not indicated (already failed medical therapy) | Weaker evidence than steroids | | Oral methotrexate | Rheumatoid arthritis, inflammatory OA | Not indicated (primary OA is non-inflammatory) | No role in primary OA | **Mnemonic:** **FAIL-THA** — **F**ailed NSAIDs, **A**nd intra-articular injection, **I**ncreased functional impairment, **L**ong duration (6+ months), **THA** is next. ### Why Not the Others? - **Repeat corticosteroid injection:** Already attempted once 3 months ago without sustained benefit. Repeat injections show diminishing returns; maximum 3–4 per joint per year. After one failed injection, progression to surgical intervention is appropriate. - **Hyaluronic acid:** Second-line injectable; weaker evidence than corticosteroids. Not indicated after corticosteroid failure. Would further delay necessary surgery. - **Oral methotrexate:** Used in rheumatoid arthritis and inflammatory arthropathies, not primary OA. No disease-modifying effect in mechanical OA.