Hardly anyone is protected from wear and tear of the joints: Almost everyone over the age of 65 shows signs of osteoarthritis – a total of 143 joints can be affected. But younger people can also be affected, especially if they put a lot of strain on their joints, such as competitive athletes. By far the most common form of osteoarthritis is knee joint osteoarthritis.
Osteoarthritis: the most common of all joint diseases
It almost always begins with pain in the morning after getting up, and the knee is stiff. Later, the pain increases, often when going down stairs, for example. Over time, the discomfort becomes more severe and the knee swells – at the latest now you seek the doctor. Osteoarthritis is classified as a rheumatic disease. According to data from the Study of Adult Health in Germany (DEGS1), 20.3 percent of people between the ages of 18 and 79 suffer from osteoarthritis. This corresponds to 12.4 million people affected. More than half of them have knee joint arthrosis, also known as gonarthrosis. However, the figures on this vary greatly depending on the source. Women are more often affected than men and with increasing age the disease frequency increases.
The knee joint does all the work
The knee joint is the largest and most important joint in the human body. It can be bent and extended like a hinge. When the knee is bent, you can also rotate the lower leg outward and inward. It does all the work, because with every step it bears the entire weight of the body. The knee joint consists of the femur, the kneecap and the tibia. The fibula is connected laterally to the tibia, but not to the knee joint. The joint surfaces of the femur and tibia do not fit together. To compensate for this, it has cartilage discs in the joint, the inner and outer meniscus. In addition, the menisci serve an even pressure load, power transmission and stability. Then another joint capsule surrounds the joint. The capsule is lined on the inside with a mucous membrane (synovium), which produces the synovial fluid (synovia). This synovial fluid is used to nourish the structures in the joint.
What happens during osteoarthritis?
Osteoarthritis can occur in any joint, but one of the most common forms of osteoarthritis is knee joint osteoarthritis. Osteoarthritis means cartilage wear and tear: a joint wears out when the cartilage covering the ends of the joint becomes rough from friction and really wears away. This causes pain, and occasionally inflammation.
Causes of osteoarthritis
Common causes are overloads, for example due to overweight, but hereditary factors also play a role. Although older people are often affected by osteoarthritis, it also affects younger people – especially if they put a lot of strain on their joints through a lot of sport or sport on one side. It is normal for the cartilage to wear down over the years and for the joint fluid to decrease. The result is a loss of elasticity and a reduced load-bearing capacity. Initially, the cartilage is affected, but as the disease progresses, the bony structures also wear out.
Primary and secondary osteoarthritis
Throughout life, all structures of the body undergo this natural aging process. However, if excessive wear and tear occurs, or if premature wear and tear occurs, this is considered a pathological change that generally requires treatment. A distinction is made between primary osteoarthritis, which is caused by natural wear and tear and aging processes, and secondary osteoarthritis, which is caused by incorrect loading. These include:
- Excessive knee loads such as competitive sports.
- Incorrect loads such as overweight
- Bone fractures and injuries that have not healed properly
- Metabolic diseases such as diabetes
- Autoimmune diseases such as rheumatism
Diagnosis of osteoarthritis
X-rays of the joint show the extent of wear and tear. But the cartilage itself cannot be visualized with an X-ray. Very often, a narrowing of the joint space indirectly indicates a thinner cartilage layer. The doctor can only see the wear of the affected, soft joint components by ultrasound.
Arthroscopy
Arthroscopy is a surgical procedure that usually involves immediate treatment.In technical language, this reflection is called arthroscopy, an examination of joints with a special endoscope – a small camera, the arthroscope. The most important alternative for arthroscopy is magnetic resonance imaging (MRI). A major advantage of this examination method is that it is a very gentle procedure.
Osteoarthritis and arthritis
Arthosis should not be confused with arthritis. Arthritis is a chronic inflammatory disease of the joints, although in very rare cases it can also affect internal organs, the skin or the eyes. It affects about 0.8 percent of the German population – women about three times more often than men. Hand and finger joints are particularly frequently inflamed. Here, pain is one of the main features of the disease, usually occurring at night or in the morning. Morning stiffness of the joints lasting longer than 15 minutes is also typical. Therapy should be given as early as possible to stop the progression of arthritis and prevent further damage. Anti-inflammatory drugs in combination with physiotherapy are used.
