Hip arthritis, also known as hip osteoarthritis, is a degenerative joint disease that affects the hip joint. It causes pain, stiffness, and loss of motion in the hip. Hip arthritis is very common in older adults, but it can occur at any age. There are several different tests that doctors use to diagnose hip arthritis.
Physical Exam
The first step is usually a physical exam. The doctor will check the hip’s range of motion and look for signs of pain, tenderness, swelling, muscle weakness, or joint deformities. They may also examine the knees and back to determine if pain is referred from other areas.
Imaging Tests
If arthritis is suspected, the doctor will probably order imaging tests to confirm the diagnosis and determine the extent of joint damage. Common imaging tests include:
- X-rays – Can detect joint space narrowing, bone spurs, cysts, and other signs of osteoarthritis.
- MRI – Provides a detailed view of soft tissues like cartilage. An MRI can detect early arthritis before changes show up on x-rays.
- CT scan – Allows a 3D view of the joint to assess the extent of damage.
- Ultrasound – Uses sound waves to see inflammation in the joint lining and other tissues.
Lab Tests
While imaging shows the structural damage to the joint, lab tests can detect inflammation and rule out other possible causes of symptoms:
- Complete blood count (CBC) – Checks for infection or inflammation.
- Erythrocyte sedimentation rate (ESR) – Measures inflammation in the body.
- C-reactive protein (CRP) test – Also detects inflammation.
- Rheumatoid factor – Screens for rheumatoid arthritis, which can affect hips.
Joint Fluid Analysis
If the hip joint is swollen, the doctor may extract a small sample of joint fluid for analysis. This is done using a procedure called arthrocentesis. The lab will test the fluid for inflammation, infection, gout crystals, and other abnormalities.
Assessing Mobility and Function
To evaluate the impact of hip arthritis, the doctor may have you perform some movements and tasks. This could include:
- Range of motion tests – Moving the hip through different planes of motion.
- Muscle strength testing – Resisting applied force to see if muscles are weak or painful.
- Gait analysis – Looking for limping, imbalance, or compensations with walking.
- Stair navigation – Watching you ascend and descend stairs.
- Sitting/standing – Observing the ease and pain level with position changes.
Your doctor will use all of this information to make or confirm an arthritis diagnosis. They can then determine the best treatment options based on the location, type, and severity of damage to your hip joint.
X-ray Findings
X-rays are often the first imaging test ordered when hip arthritis is suspected. An x-ray can confirm joint damage and narrowing of the space between bones. Here are some of the specific findings that may be seen:
- Joint space narrowing – The hip joint is comprised of the ball-shaped femoral head that fits into the socket-shaped acetabulum. Arthritis causes this space between bones to become reduced.
- Subchondral sclerosis – The bone right beneath the cartilage becomes hardened.
- Osteophytes – Bone spurs or extra bits of bone grow at the joint margins.
- Subchondral cysts – Fluid-filled sacs form in the bone next to the joint.
- Loose bodies – Small fragments of cartilage break off into the joint space.
The x-ray may show generalized joint space narrowing or specific loss of cartilage in certain areas. The severity and location of damage guides treatment.
MRI Findings
An MRI uses magnetic fields to create detailed images of the soft tissues around the hip joint, including:
- Cartilage – An MRI detects early cartilage thinning and loss. Over time, large areas of complete cartilage loss may be noted.
- Synovium – The joint lining becomes inflamed and thickens.
- Labrum – This ring of cartilage around the socket may tear or detach.
- Ligaments – Thickening and scar tissue develops in supporting ligaments.
- Muscles – Atrophy, tears, or other abnormalities may be found.
- Bones – Bone marrow lesions, cysts, and bony growths apparent.
An MRI of the hip allows the surgeon to see the specific areas of damage. This helps guide optimal treatment choices.
Common Symptoms
The typical symptoms of hip osteoarthritis include:
- Joint stiffness, especially with prolonged inactivity or in the morning
- Aching pain in the hip that worsens with activity
- Loss of flexibility and range of motion
- Joint tenderness
- Swelling or inflammation
- Difficulty walking or bending
- Pain or stiffness that keeps you awake at night
- Limping
- Clicking, crunching or grinding noises with hip movement
The pain may radiate down the thigh or into the knee in some cases. Hip arthritis pain can range from mild to severely disabling.
Risk Factors
Certain factors increase the chances of developing hip arthritis:
- Age – The risk rises significantly after age 50.
- Obesity – Excess weight puts strain on hip joints.
- Joint injury – Prior fractures, dislocations or trauma predispose to arthritis.
- Overuse – Occupations or activities requiring repeated heavy lifting can stress the hip joint over time.
- Genetics – Inherited musculoskeletal conditions often lead to arthritis.
- Dysplasia – Congenital shallow hip sockets or other joint irregularities.
Osteoarthritis that arises without injury or an underlying defect is considered “primary” arthritis. “Secondary” arthritis is a consequence of pre-existing joint abnormalities or trauma.
When to See a Doctor
See your doctor promptly if you have persistent hip pain or any signs of arthritis. Important times to seek medical evaluation include:
- Hip pain that does not resolve with a few days of rest
- Increasing difficulty with hip mobility or function
- Stiffness lasting more than 30 minutes after arising
- Pain at night or while resting
- Swelling or tenderness over the hip joint
- Limping or joint instability
- Unexplained weight loss
- Hip pain after an injury or fall
Early treatment can help manage symptoms and slow the progression of arthritis damage.
Causes
The main cause of hip osteoarthritis is cartilage breakdown in the joint over time. Cartilage is the slick, cushioning surface on bone ends that allows joints to glide smoothly. Arthritis develops when cartilage deteriorates faster than the body can repair it. Specific contributors to cartilage loss include:
- Aging – Cartilage becomes more brittle and prone to injury as people get older.
- Genetic factors – Gene mutations may increase cartilage deterioration.
- Biomechanical stress – Excessive force across the joint surfaces damages cartilage.
- Inflammation – The immune system attacks joint tissues, thinking they are foreign.
- Injury – Trauma, such as a fracture or dislocation, often leads to arthritis later on.
- Obesity – Excess weight puts extra pressure across hip cartilage.
As cartilage is lost, the bones of the hip joint rub together causing pain, stiffness, and loss of smooth motion. Bits of bone or cartilage may break off into the joint space.
Prevention
While hip arthritis cannot always be prevented, the following measures can reduce your risk:
- Maintain a healthy weight to avoid stressing hip joints.
- Build muscle strength and flexibility through exercise to support and protect joints.
- Use proper form and technique with sports and high-impact activities.
- Take frequent breaks, stretch, and modify activities that aggravate hip pain.
- Avoid occupational overuse by alternating tasks and using correct lifting postures.
- Stop smoking, which may contribute to cartilage damage.
- Consume joint-healthy nutrients like glucosamine, chondroitin, vitamin D, and omega-3s.
Making lifestyle modifications at the first signs of hip pain may help alleviate symptoms and slow further arthritis progression.
Treatment
Hip arthritis treatment focuses on relieving pain, maintaining mobility, and improving function. Both medication and non-medication therapies are used. Some treatment options include:
- Pain relievers – Anti-inflammatory drugs (NSAIDs), acetaminophen, opioids, creams, etc.
- Joint injections – Steroids can temporarily reduce inflammation and pain.
- Physical therapy – Exercises, stretches, and modalities help strengthen muscles and support joints.
- Weight loss – For overweight patients, shedding pounds reduces hip joint stress.
- Assistive devices – Canes, walkers, raised toilet seats, and other aids facilitate daily tasks.
- Surgery – Joint repair, reshaping procedures, or total hip replacement may be necessary.
Treatment is tailored to each patient’s symptoms, joint damage, age, activity level, and other health factors. Relief is often achieved through a combination of medical and lifestyle approaches.
Conclusion
Hip arthritis is a common cause of chronic hip pain and loss of function in older adults. Key tests for diagnosing hip arthritis include physical examination, imaging studies like x-rays or MRI, lab work, and analysis of hip joint fluid if present. Typical symptoms include stiffness, reduced range of motion, swelling, and aching pain that worsens with activity. While sometimes related to prior injury, hip arthritis mainly arises due to gradual cartilage loss from aging, wear-and-tear, and inflammation. Staying active, maintaining a healthy weight, and avoiding overuse of the joint may help reduce the risks. Anti-inflammatory medications, injections, physical therapy, lifestyle changes, and surgery if needed can all help manage arthritis hip pain and stiffness.