What is osteoarthritis?
Osteoarthritis is sometimes described as "wear and tear" of the joints, but the disease is more complex than that. In osteoarthritis, the structure and function of the joint gradually change over time. The disease affects the entire joint, including cartilage, bone, the joint capsule and surrounding tissues. Osteoarthritis most commonly occurs in the knees, hips and hands, but it can affect most joints in the body.
In a healthy joint, cartilage acts as a shock-absorbing surface that helps distribute load and allows smooth movement. In osteoarthritis, the properties of the cartilage change while other parts of the joint are also affected. This can lead to pain, stiffness and reduced function.
Over time, the bone beneath the cartilage can also change and bone spurs can develop. How quickly the disease progresses varies between individuals and is influenced by several factors, including age, genetics, previous joint injuries, physical load and body weight.
Common symptoms of osteoarthritis
The most common symptoms of osteoarthritis are joint pain, stiffness and reduced function. Symptoms often develop gradually and can vary over time. Many people find that the joint feels stiff in the morning or after a period of sitting still, but that mobility improves once they get moving.
Pain often occurs when the joint is under load and may, for example, be noticeable when climbing stairs, getting up from a chair or walking longer distances. In some people, the joint may also become swollen and feel tender.
The experience of osteoarthritis varies between individuals. Some people have mild symptoms, while others are more affected in their daily lives by pain, reduced mobility and reduced physical function.
Risk factors and causes
Osteoarthritis develops through an interaction between several different factors. The risk increases with age, genetic factors, previous joint injuries and overweight or obesity. The shape and function of the joint can also affect the risk of developing the disease.
Body weight plays an important role, particularly in osteoarthritis of the knee and hip joints, because increased load on the joints over time can contribute to the development of symptoms. At the same time, the joints are not affected solely by mechanical load. Research suggests that metabolic and inflammatory processes may also play a role.
Physical inactivity and reduced muscle strength can contribute to poorer joint function and increased symptoms, while regular physical activity helps support joint health. Previous joint injuries and prolonged or very high loads on the joints, for example in certain types of work or elite sport, can also increase the risk of developing osteoarthritis later in life.
How does body weight affect osteoarthritis?
Overweight and obesity are important risk factors for both the development and worsening of osteoarthritis, particularly in the knee and hip joints. A higher body weight means that the joints are exposed to greater loads during everyday activities such as walking, standing and climbing stairs. This can contribute to increased pain and reduced function over time.
However, the link between body weight and osteoarthritis is not only about mechanical load. Adipose tissue is biologically active and produces signalling substances that can affect inflammation and other processes in the body. Research suggests that these factors may contribute to the development of osteoarthritis and affect how the disease is experienced.
It is likely that the combination of increased load on the joints and altered biological processes explains why overweight is linked to an increased risk of osteoarthritis and more pronounced symptoms.
Treatment of osteoarthritis
Education about the disease, physical activity and, when needed, weight loss form the basis of treatment for osteoarthritis. The aim is to reduce symptoms, improve function and create the conditions for an active everyday life. When needed, treatment can be supplemented with pain-relieving medicines or surgery.
With osteoarthritis, it can feel natural to want to take the load off the joint when it hurts, but regular physical activity is actually one of the most important treatments and is strongly recommended.
When you move, the joint works like a pump. Movement helps the synovial fluid circulate, which helps the cartilage get the nutrients it needs.
Physical activity also strengthens the muscles around the joint, which can reduce the load and improve stability. Many people also find that regular movement reduces pain and stiffness and improves function in everyday life.
The most important thing is to find a level of activity that works for you. Even shorter walks and everyday movement can make a difference over time. Strength training is particularly valuable because stronger muscles can take pressure off the joint and improve stability around the affected joint.
For people with overweight or obesity, weight loss can reduce the load on the joints and contribute to reduced pain and improved function. If symptoms persist despite self-care and exercise, pain-relieving medicines can be a complement. In severe osteoarthritis with pronounced symptoms, joint replacement surgery may be a treatment option when other treatments do not provide sufficient effect.
Can obesity medicines relieve symptoms of knee osteoarthritis?
Research shows that weight loss can reduce pain and improve function in people with knee osteoarthritis and overweight or obesity. Reduced body weight can take pressure off the knee joint and make it easier to move and be physically active.
In the STEP 9 study, people with obesity and knee osteoarthritis were treated with semaglutide. The treatment led to significant weight loss, and participants reported less knee pain and better physical function compared with those who received placebo.
Semaglutide is not a treatment for osteoarthritis itself, but it can be a tool for achieving weight loss in people with obesity, which in turn can help reduce symptoms and improve function.
Medication for obesity does not replace physical activity, strength training or other osteoarthritis treatment, but for some people it can be a valuable complement.
When should you seek healthcare?
It may be a good idea to seek healthcare if you have recurring joint pain, stiffness or swelling that affects your daily life, mobility or physical activity. An early assessment can help determine the cause of the symptoms and provide guidance on appropriate treatment.
A physiotherapist or primary care centre can help with information about the disease, individually adapted exercise and other measures aimed at reducing pain and improving function. For people with overweight or obesity, weight loss can also be an important part of treatment, as reduced body weight can take pressure off the joints and contribute to reduced symptoms.
Frequently asked questions about osteoarthritis (FAQ)
Can osteoarthritis be completely cured?
There is currently no treatment that completely cures osteoarthritis or restores the joint to its original condition. However, there are several effective treatments that can reduce pain, improve function and help many people live an active life with the disease.
Physical activity, strength training, patient education and, when needed, weight loss form the basis of treatment. For people with overweight or obesity, reduced body weight can take pressure off the joints and contribute to less pain and better mobility.
Does physical activity cause the cartilage to wear out even more?
No. Research shows that appropriately adapted physical activity and exercise do not accelerate osteoarthritis or cause the cartilage to "wear out" more quickly. On the contrary, regular physical activity is one of the most important treatments for osteoarthritis and is recommended in national and international guidelines.
When you move, the joint works like a pump. Movement helps the synovial fluid circulate, which helps the cartilage get the nutrients it needs.
Movement helps maintain joint function, strengthen the muscles around the joint and improve mobility. Many people also experience reduced pain and better physical function when they exercise regularly.
It is common for the joint to feel sore or temporarily more strained when you start exercising or increase your activity level. A temporary increase in pain after exercise should subside within about 24 hours. If the symptoms persist or worsen, it may be helpful to adapt the exercise together with a physiotherapist or another healthcare professional.
Should I get help from a physiotherapist or occupational therapist for my osteoarthritis?
Yes, many people with osteoarthritis can benefit from support from a physiotherapist or occupational therapist. A physiotherapist can help you get started with individually adapted exercise that improves strength, mobility and function, while providing advice on how you can remain physically active despite pain and stiffness.
An occupational therapist can provide support with everyday activities and, when needed, recommend aids or strategies that reduce the load on the joints. The aim is to make it easier to manage everyday activities and maintain a good quality of life.
For many people with osteoarthritis, exercise, patient education and self-care form the basis of treatment, and physiotherapists and occupational therapists therefore play an important role in long-term care.
.svg)