Medically reviewed by Dr. Rebecca L. Carter, Orthopaedic Specialist | Last updated: June 2026
Hip osteoarthritis is less discussed than knee OA but is equally debilitating — and its referral patterns can be confusing. Hip OA often causes pain in the groin, inner thigh, or buttock rather than the hip itself, leading people to assume they have a back problem or knee problem for months before the correct diagnosis is made. Understanding what hip OA feels like, how it differs from other hip conditions, and what exercises actually help can prevent years of incorrect management.
Hip Osteoarthritis vs Knee OA: Key Differences
While both involve cartilage degeneration, the clinical presentation and management differ:
- Pain location: Knee OA is straightforward — pain is at the knee. Hip OA typically causes groin pain, sometimes with referral to the inner knee or buttock. People with hip OA often say their knee hurts — this is referred pain from the hip, not a knee problem.
- Movement pattern: Hip OA restricts internal rotation first — the ability to rotate the leg inward. This is the most consistent early clinical sign.
- Impact on daily life: Hip OA makes walking long distances, climbing stairs, putting on shoes and socks, getting in/out of cars, and sexual activity painful first — before affecting simple standing.
- Weight bearing: Standing and walking on one leg (as in stair climbing) is particularly provocative for hip OA
Diagnosis: What Your X-Ray Shows
Hip OA is graded similarly to knee OA on the Kellgren-Lawrence scale (0–IV). X-rays show:
- Grade I: Possible osteophytes, minimal joint space narrowing
- Grade II: Definite osteophytes, mild narrowing of joint space
- Grade III: Multiple osteophytes, moderate narrowing, mild subchondral sclerosis
- Grade IV: Large osteophytes, severe narrowing or loss of joint space, bone-on-bone contact
As with knee OA, X-ray grade does not perfectly correlate with pain severity — some Grade III patients have minimal pain; some Grade I patients have severe symptoms. Management should be guided by symptoms, not X-ray appearance alone.
Non-Surgical Management: What the Evidence Supports
Exercise: Most Important Intervention
Exercise is the single most evidence-based treatment for hip OA — above all medications and injections. A 2019 Cochrane review confirmed that exercise reduced hip OA pain by 29% and improved function significantly. The best exercise programme combines:
- Hip strengthening: Targeting the hip abductors (gluteus medius), hip extensors (gluteus maximus), and hip flexors
- Range of motion: Gentle hip circumduction and rotational movements to maintain joint mobility
- Aerobic conditioning: Walking, cycling (recumbent or upright), and swimming — all low-impact
Weight Reduction
Each kilogram of excess body weight places approximately 3 kg of additional force on the hip during walking. A 5 kg weight loss reduces hip loading by 15 kg per step. For people who are overweight, weight loss is the single most modifiable risk factor for hip OA progression.
Key Exercises for Hip OA (Physiotherapy-Approved)
1. Side-Lying Hip Abduction (Clam)
Lie on your side, knees bent to 45°. Keeping feet together, lift the top knee upward like a clamshell opening. Hold 2 seconds, lower slowly. 3 sets of 15 reps each side. Targets gluteus medius — typically the weakest muscle in hip OA patients.
2. Standing Hip Extension
Stand at a wall for support. Keeping the leg straight, slowly extend it backward 20–30°. Hold 2 seconds. 3 sets of 12 reps each side. Strengthens gluteus maximus — essential for walking and stair function.
3. Hip Circumduction
Stand on one leg (hold wall for balance). Move the opposite leg in a slow circular motion — 10 clockwise, 10 counterclockwise. Gentle mobilisation that maintains joint range without loading.
4. Seated Hip Flexion
Sit in a chair. Lift one knee toward the chest, hold 3 seconds, lower. Alternate legs. 2 sets of 12 reps. Maintains hip flexor function that is often reduced in advanced OA.
5. Gentle Hip Internal Rotation Stretch
Sit on a chair. Cross one ankle over the opposite knee (figure-4 position). Gently press down on the crossed knee while leaning slightly forward — feel a stretch in the outer hip. Hold 30 seconds each side. This targets the hip external rotators that become tight in OA.
When Hip Replacement Is Necessary
Total hip replacement (THR) is one of the most successful procedures in orthopaedic surgery — with over 95% patient satisfaction at 10 years. It is typically recommended when:
- Significant pain and disability persist despite 3–6 months of appropriate conservative management
- X-ray confirms Grade III–IV OA with bone-on-bone contact
- Pain significantly impairs daily activities and quality of life
- Patient is medically fit for surgery
See also our guides on knee replacement recovery and cartilage repair options.
References
- Fransen, M. et al. (2014). Exercise for osteoarthritis of the hip. Cochrane Database of Systematic Reviews.
- Bannuru, R.R. et al. (2019). OARSI guidelines for non-surgical management of osteoarthritis. Osteoarthritis and Cartilage, 27(11).
- Cibulka, M.T. et al. (2017). Hip pain and mobility deficits: hip OA clinical practice guidelines. Journal of Orthopaedic and Sports Physical Therapy.
