Arthritis of the Hip

How the hip joint is damaged

The hip is a ball-and-socket joint. The ball at the top of the thighbone (femoral head) fits into the socket of the pelvis (acetabulum). Both surfaces are covered with smooth articular cartilage and lubricated by joint fluid.

In osteoarthritis, cartilage gradually thins and roughens. The bone beneath thickens, bone spurs (osteophytes) grow at the edges, and the joint lining becomes inflamed. Eventually bone can rub on bone. In inflammatory arthritis, the immune system attacks the joint lining (synovium), which damages cartilage from the start.

Types of hip arthritis

Symptoms

Early signs of hip arthritis

• aching in the groin or front of the thigh, sometimes the buttock
• pain spreading down to the knee. Some people feel hip arthritis only in the knee
• stiffness after sitting or first thing in the morning, easing within half an hour
• pain after walking, standing or exercise, relieved by rest
• difficulty bending to put on socks, shoes or cut toenails

As it progresses

• pain at rest and at night
• a limp, or leaning over the painful side when walking
• reduced range of motion, especially rotating the leg inward
• grinding, clicking or catching
• one leg seeming shorter
• difficulty climbing stairs, getting in and out of cars and chairs

Where hip pain is felt

Causes and risk factors

• Age
• Genetics and family history
• Hip shape: dysplasia, femoroacetabular impingement, childhood hip conditions such as Perthes disease or slipped capital femoral epiphysis
• Previous injury or fracture
• Obesity: increases load and inflammation
• High-impact sport or heavy manual work over many years
• Inflammatory diseases and gout
• Avascular necrosis from steroids, alcohol or sickle cell disease

Diagnosis

1. History and examination: your doctor will watch you walk, check tenderness, and move the hip. Pain and limitation when rotating the hip inward are typical of hip joint arthritis.
2. X-ray: shows joint space narrowing, bone spurs, and changes in the bone. X-rays are often enough to diagnose osteoarthritis.
3. MRI: for early arthritis, labral tears, avascular necrosis or unclear cases.
4. Blood tests: rheumatoid factor, anti-CCP, CRP and ESR when inflammatory arthritis is suspected.
5. Joint aspiration: to exclude infection or crystals when the hip is hot and swollen.
6. Diagnostic injection: numbing medicine injected into the joint confirms whether the pain comes from the hip.

Treatment

Exercise and physical therapy

Exercise is the core treatment in all major guidelines. It reduces pain and improves function as much as many medicines.

• Strengthening: gluteal muscles, hip abductors, quadriceps and core
• Range of motion: gentle hip stretches
• Low-impact aerobic exercise: walking, cycling, swimming, water aerobics
• Tai chi and balance training

Some pain during exercise is acceptable if it settles within a few hours to the next day.

Weight management

Losing even 5 to 10% of body weight reduces load on the hip and improves pain in people who are overweight.

Medicines

• Topical NSAIDs are less effective at the hip than at the knee because the joint is deep.
• Oral NSAIDs such as ibuprofen or naproxen help many people. Use the lowest effective dose for the shortest time. Avoid them with kidney disease, stomach ulcers, heart failure or blood thinners.
• Acetaminophen (paracetamol) has small benefit for osteoarthritis but is sometimes used when NSAIDs are unsuitable.
• Duloxetine can help chronic pain.
• Disease-modifying drugs and biologics for rheumatoid arthritis and ankylosing spondylitis.
• Opioids are not recommended for long-term arthritis pain.

Injections

Corticosteroid injections into the hip joint, usually guided by ultrasound or X-ray, can relieve pain for weeks to months. Hyaluronic acid and platelet-rich plasma injections are not recommended by major guidelines for hip osteoarthritis.

Walking aids and daily life

A cane held in the hand opposite the painful hip reduces load significantly. Raised toilet seats, long-handled shoehorns, sock aids and firm, higher chairs help daily tasks.

Surgery

• Total hip replacement: replaces the damaged ball and socket with metal, ceramic and plastic parts. It is one of the most successful operations in medicine, with most people gaining major pain relief, and modern implants commonly lasting 20 years or more. Recovery to normal daily activity takes about 6 to 12 weeks.
• Hip resurfacing: an option for some younger, active men.
• Osteotomy: reshaping the bones in younger people with dysplasia before major arthritis develops.
• Hip arthroscopy: for impingement or labral tears without significant arthritis. It does not help established arthritis.

Surgery is considered when pain and limitation persist despite non-surgical treatment and affect quality of life.

Outlook

Hip osteoarthritis usually progresses slowly over years, though the rate varies. Some people stay stable for a long time with exercise and weight management. For those who reach advanced arthritis, hip replacement reliably restores mobility.

Frequently asked questions

What are the early signs of hip arthritis?

Early signs include aching in the groin or front of the thigh, stiffness after sitting or on waking that eases within 30 minutes, pain after walking or standing, and difficulty putting on socks or shoes. Some people first notice pain in the knee.

What is the best exercise for hip arthritis?

A combination of strengthening exercises for the hip and thigh muscles, gentle stretching, and low-impact aerobic activity such as walking, cycling or swimming works best. A physical therapist can design a program. Tai chi also helps pain and balance.

Is walking good for hip arthritis?

Yes. Regular walking at a comfortable pace strengthens muscles, helps weight control and maintains joint movement. Use supportive shoes, walk on even surfaces, break walks into shorter sessions if needed, and use a cane in the opposite hand if it helps.

When do you need a hip replacement?

Hip replacement is considered when arthritis pain and stiffness significantly limit daily activities or sleep despite exercise, weight management, medicines and injections. X-rays confirming advanced joint damage support the decision. There is no strict age limit.

Why does hip arthritis cause knee pain?

The hip and knee share nerve pathways, so pain from the hip joint can be felt in the front of the thigh and knee. This referred pain is common, especially in children and older adults, and a knee examination will be normal.