Hip osteoarthritis (coxarthrosis)

Osteoarthritis of the hip is due to wear and tear on the protective cartilage layer of the bones in the hip joint. This leads to increasing pressure on the bones and gradually reduces the mobility of the joint. Pain in the hip and groin area when moving are often the first signs. Most people with osteoarthritis of the hip are over the age of 45.

How osteoarthritis of the hip develops varies considerably. Over time, many people experience only mild symptoms that have little or no effect on them. In some cases, however, the condition advances rapidly and can have a major impact on quality of life.

Exercise and physiotherapy are two of the main measures used to treat osteoarthritis of the hip. People can also take non-steroidal anti-inflammatory drugs (NSAIDs) and lose weight if they are very overweight.

Joint replacement is an option to consider if the person is suffering increasing, severe pain, sleep problems and everyday limitations and if the osteoarthritis is at an advanced stage.

With osteoarthritis of the hip, the pain is initially often only felt when the person exerts themselves or after strenuous activity. It usually begins gradually and can drag on for several years or months.

People with osteoarthritis of the hip often report pain when climbing stairs, walking or moving their (raised) thigh, for example, when crossing their legs. For some, the pain extends as far as the inner thigh, the buttocks or knee.

The hip joint may feel slightly stiff for up to 30 minutes in the morning or after prolonged periods of rest. More prolonged morning stiffness is more likely to be a different condition such as rheumatoid arthritis. If the hips are in pain when the person is at rest or during the night, the osteoarthritis has usually already reached an advanced stage.

If the hip joint is healthy, both the head of the femur and the socket of the pelvic bone are surrounded by cartilage. If this cartilage layer becomes thinner, this may result in osteoarthritis of the hip: the cartilage softens, begins to tear and loses strength. Osteoarthritis is therefore also called “degenerative joint disease”, or simply “joint degeneration”.

Healthy, resilient joint cartilage provides the bones with smooth sliding surfaces, enabling movement without friction. Cartilage cells cannot really “grow back” by themselves and therefore do not renew themselves as easily as other tissues. Once damage has occurred, it therefore usually remains permanent.

Often, many factors play a role in the development of osteoarthritis of the hip. Various circumstances make wear and tear more likely, including the following:

• family history
• congenital anomalies of the hip (hip dysplasia)
• rare congenital hip disorders
• inflammatory joint diseases, such as rheumatoid arthritis
• previous hip injuries, e.g. bone fractures in the hip joint or a dislocated hip joint
• hip impingement – where bony spurs on the joint cause pinching to occur between the head of the femur and socket
• obesity
• heavy physical work, for example construction work
• types of sport that put intense pressure on the body such as football and handball

In Germany, around 5 percent of adults have osteoarthritis of the hip with symptoms. The condition affects more women than men.

The joints change increasingly with age, as the cartilage wears down and the joint cavity becomes narrower. This means that the bones are not as well protected against pressure. This results in new bone substance being formed. The new bone formations, known as bone bridges or osteophytes, are visible on X-rays.

These processes of wear and tear and repair on bones can balance each other out for a long time. Joint changes therefore do not always lead to symptoms. 

How osteoarthritis of the hip develops varies considerably. A large study in the Netherlands observed how the disease progresses by regularly examining patients over a period of 5 years. This produced the following results:

• 40 percent had mild, relatively constant pain over the entire period.
• 20 percent had moderate, likewise relatively constant pain.
• 25 percent had moderate pain that became more intense over the 5 year period.
• 15 percent suffered from persistent, severe pain.

A diagnosis can usually be made if a patient presents with the typical symptoms of osteoarthritis of the hip. One typical symptom is the type of “start-up pain” that occurs after prolonged periods of inactivity and that disappears again quickly with movement of the joint.

The doctor takes a detailed medical history, asking specific questions about how the condition has progressed so far and its symptoms, for example: how long has the person been experiencing pain, when does it occur, how does it feel? Does the pain only occur when moving or also when at rest? Are the joints stiff in the morning? Were there any previous injuries?

As well as asking questions, the doctor feels the joint and examines how well it can move, looks at the person’s gait and checks whether there is any pelvic obliquity or whether the legs are of different lengths.

X-rays, ultrasound scans, computed tomography (CT) scans and magnetic resonance imaging (MRI) are often not very helpful in the case of osteoarthritis. Research indicates that only 25 percent of people with osteoarthritis visible on an X-ray actually suffer pain. Therefore, this type of imaging does not often provide any further useful information.

However, imaging tests or blood tests may be useful if the symptoms indicate another condition, such as rheumatoid arthritis or gout.

The treatment will depend on how intense and distressing the pain is. The stage of the condition, the patient’s overall state of health and individual considerations, such as the patient’s job and their expectations of the treatment, are also taken into account.

The recommended measures include:

• exercise therapy, such as physiotherapy with exercises to strengthen the thigh and hip muscles, rehabilitation sports and exercise, functional training, aquarobics and tai chi
• use of non-steroidal anti-inflammatory drugs (NSAIDs)
• losing weight if very overweight
• wearing flat, well-cushioned and comfortable shoes

Exercise and regular movement are often difficult to imagine for people with joint pain. Some are afraid that they will damage their joints further. In fact, studies prove otherwise. They suggest that strengthening, mobility and endurance training reduce the pain and can improve joint function. Hip surgery may even be delayed as a result.

For more detailed information, such as what you can do to strengthen your hip joints, visit gesundheitsinformation.de.

Osteoarthritis of the hip can also be treated with cortisone injections. Studies indicate that these relieve pain for several weeks – especially if the patient has osteoarthritis in one joint only. They may be used if the hip joint is acutely inflamed and very painful or if other treatments have been unsuccessful or are not possible. However, cortisone injections are not a long-term treatment option, as they can cause side effects. It is also unclear whether they are effective in the long term.

If the symptoms are having a severe impact on everyday life and if they do not significantly improve with pain medication and exercise, an artificial hip joint may be needed. Doctors also refer to this as a total hip replacement (THR) or total hip arthroplasty (THA). An artificial hip joint can significantly alleviate the symptoms in over 90 percent of people.

The effectiveness of many other treatments remains unproven. These include:

• analgesic creams 
• medication containing paracetamol for pain relief
• duloxetine – a medication used to treat depression or diabetic neuropathy, among other things
• hyaluronic acid injections
• smoothing the cartilage using arthroscopy
• ultrasound therapy, laser treatment, electro-therapy (TENS treatment), specific heat-based therapies (diathermy)
• gold implantation
• X-ray stimulation therapy (also known as orthovoltage radiation therapy) – where the joint is treated with low-level X-ray radiation over several weeks
• dietary supplements, for example with chondroitin, glucosamine or vitamins
• herbal supplements, for example based on rampion or stinging nettles
• homeopathy
• food or food extracts, including those based on soy or avocado

Advanced osteoarthritis of the hip can make everyday life more difficult on many levels. However, over time, many people learn to cope well with life despite their condition – for example, they take more time for different kinds of strenuous activity, such as household work, and adjust what they do accordingly.

Walking aids can make movement easier, both inside and outside the apartment – walking sticks, walkers or wheeled walkers take pressure off the joints. Experts – physiotherapists and occupational therapists, as well as medical practitioners of various specialties, such as orthopedics, rheumatology and geriatrics – can explain how to use and correctly set up these aids.