Introduction

Photo of a couple sitting outdoors (PantherMedia / Werner Heiber)

Osteoarthritis is a degenerative ("wear-and-tear") joint disease that typically leads to pain and stiffness in joints. If the symptoms get worse, they can greatly affect your ability to move.

Many people have osteoarthritis in older age. Some already develop it in middle age. Although osteoarthritis can occur in most of the joints in the body, it mainly affects the

  • knees,
  • hips,
  • fingers and
  • spine (facet syndrome).

Symptoms

In the early stages of osteoarthritis, the joint usually only hurts when you put strain on it. In the knee or hip area, people then often feel a stabbing pain during activities like jogging.

The pain can get worse over time, limiting what you can do in everyday life. The joints may then feel stiff too – particularly after resting for a long time, for instance after getting up in the morning. It’s also normal to have “start-up pain” that gets better quite quickly as you continue moving the joint. If the morning joint stiffness lasts longer than 30 minutes, it is more likely to be rheumatoid arthritis.

In very advanced stages of osteoarthritis, the pain occurs at rest too. This can be hard to cope with and affect your sleep. The symptoms often come and go in milder and more severe phases.

Osteoarthritis can also make the joints become sensitive to pressure, swollen and stiff. In later stages of the disease, the joint may become deformed too.

Causes

Inside joints, the ends of bones are covered with a layer of tough cartilage. Cartilage is made of special cells that can repair themselves to a certain extent. But they can only repair themselves if the joint is moved enough. Cartilage doesn't have any blood vessels in it. Instead, nutrients are transported as a result of alternating pressure, for instance when walking. It’s a bit like a wet sponge that is being squeezed and released: the waste products of metabolism are pushed out of the cartilage and then nutrients are absorbed from the fluid in the joint (synovial fluid).

But cartilage can’t prevent normal wear-and-tear forever. Over time, the cartilage becomes thinner, with a rougher surface. Normal, age-related wear-and-tear of joints occurs in most people as they get older. But this usually doesn't cause any symptoms: Only 25% of all people who have osteoarthritis (as seen on x-ray images) also have pain. In very advanced stages of osteoarthritis, the cartilage may be so worn down in some places that the bone is no longer covered by cartilage. Treatment is only needed if you have symptoms.
Illustration: Early and advanced osteoarthritis - as described in the article

Risk factors

Anyone can develop osteoarthritis. The main risk factor is age: 10% of 30- to 40-year-olds say that they have osteoarthritis, compared to 40% of 60- to 70-year-olds.

Certain factors can speed up the wear-and-tear of cartilage:

  • Your genes (it can run in your family)
  • Certain sports that put a lot of stress on joints, like football or handball
  • Work-related activities that involve a lot of kneeling, squatting or lifting heavy objects
  • Knee injuries such as a torn cruciate ligament or a torn meniscus
  • Joint diseases, for instance of the hip
  • Being very overweight

Outlook

The course of osteoarthritis can vary quite a lot from person to person. It often progresses slowly over the years, in phases of milder and more severe symptoms that you can learn to live with. But sometimes the symptoms suddenly get a lot worse. The bones in the joint may change over time: Bony projections (lumps) then grow along the edges of the bones. These are known as bone spurs. They can prevent the joint from moving properly and lead to permanent (chronic) pain. In advanced stages of the disease, you might feel a grating sensation or hear a noise when you move the joint – for example, if the bones rub against each other.

Diagnosis

Osteoarthritis can usually be diagnosed based on the typical symptoms. If there is any doubt, an x-ray can be done. If typical changes can be seen on the x-ray image – such as a very narrow joint cavity – the diagnosis is clear and no other examinations or tests are needed.

Sometimes the symptoms are less typical, or other diseases (like rheumatoid arthritis) have to be ruled out. It can then make sense to do blood tests, an MRI scan or an ultrasound scan.

Treatment

A lack of movement can speed up the breakdown of cartilage. It also weakens the muscles, which makes it even harder to move your body. So it’s very important for people who have osteoarthritis to get enough exercise and stay active. This is especially true if the knees or hips are affected.

There is currently no cure for osteoarthritis. But there are a wide range of treatments to relieve the symptoms. The most suitable choice of treatment will depend on various factors, including which joint is affected.

Only a few treatments have been reliably proven to slow down the progress of osteoarthritis or relieve the symptoms. Depending on which joint is affected, the most effective treatments include exercise therapy, rehabilitation exercises and painkillers. People who are very overweight are advised to lose weight, particularly if they have osteoarthritis of the knee or hip. Occupational therapy can be helpful in people who have osteoarthritis of the fingers or hands. For instance, they can learn how to avoid activities that put a lot of strain on the joints, or how to do them in a joint-friendly way.

Various aids, devices and gadgets can help to reduce the strain on joints too. These include walking sticks (if your knees and/or hips are affected) and special pens or devices – for instance, to help you grip objects or open things like jars and bottles (if your fingers are affected). Sometimes special splints are used to stabilize the joint too.

Many treatments have not been proven to help in people who have osteoarthritis. These include acupuncture, arthroscopy (keyhole surgery), herbal products, dietary supplements, hyaluronic acid injections, ultrasound therapy and transcutaneous electrical nerve stimulation (TENS).

In advanced osteoarthritis of the knee or hip, the damaged parts of the joint can be partially or fully replaced with an artificial joint, known as an endoprosthesis.

Further information

When people are ill or need medical advice, they usually go to see their family doctor first. Read about how to find the right doctor, how to prepare for the appointment and what to remember.