The fast facts:
- About 600,000 Dutch people have osteoarthritis of the knee.
- Women are more likely to have osteoarthritis in the knee than men.
- Smoking and obesity increase the risk of developing knee osteoarthritis
- Each year, approximately 21,000 men and 33,000 women develop knee osteoarthritis
- Knee osteoarthritis increases with age
- Each year, 24,000 people undergo surgery for a new knee
Causes of osteoarthritis
Exactly how osteoarthritis forms is not entirely clear. What we do know is that osteoarthritis increases with age. We distinguish between different forms of osteoarthritis. Osteoarthritis can occur as a result of natural aging. We then call this degenerative osteoarthritis. Osteoarthritis can also occur as a result of an accident. We call this post-traumatic osteoarthritis. The joint is then damaged, for example, by a fall. Osteoarthritis may also occur as a result of rheumatoid arthritis (RA). In degenerative osteoarthritis and osteoarthritis as a result of RA, there is often osteoarthritis in several joints. Normally, cartilage is a smooth structure. During aging or damage, the quality of the connective tissue decreases. As we age, cartilage cannot repair itself properly like, say, a muscle can. The reason for this is that cartilage is poorly supplied with blood. The degree of arthritis does not always determine the degree of complaints. It may be that people experience relatively few symptoms with a severe osteoarthritis of the knee. There may also be a lot of symptoms and pain with little osteoarthritis in the knee. The degree of pain depends on many different factors such as strength of the muscles around the knee, level of physical activity, physically demanding work. Cartilage itself has little to no pain sensors. So cartilage itself cannot hurt. Because of osteoarthritis, there is an inflammatory process that leads to irritation of the capsule, synovial fluid (synovium) and muscles and tendons around the knee.
Anatomy and function of cartilage in the knee
A joint is a place in the body where two parts of the bone meet. In the knee, this is the femur (upper leg) and the tibia (lower leg). Between these bone parts is cartilage which has a very smooth surface so that it can move smoothly. In order to steer the knee joint properly, there are different types of ligaments in and around the knee. On the inside and outside are the collateral ligaments. Between the femur and tibia is the inner and outer meniscus which acts as a shock absorber between these two bone parts. In the knee is the anterior and posterior cruciate ligament. We distinguish different types of cartilage: hyaline, elastic and fibrous cartilage. Hyaline cartilage is the most common in our body and is also found on the ends of our bones. The function of cartilage is mainly to keep the joint moving smoothly and acts as a shock absorber along with the meniscus in the knee. Osteoarthritis in the knee is also known as gonarthrosis in the medical community.
Symptoms of knee osteoarthritis
Osteoarthritis in the knee can lead to a variety of symptoms:
- Startup symptoms especially in the morning are a common symptom in knee osteoarthritis. Also after sitting for a longer period of time and starting up again, the knee can give symptoms.
- Climbing stairs and walking for long periods of time often produces a reaction in the knee.
- A limitation in mobility. Especially towards stretching. Bending usually goes a little easier.
- Osteoarthritis of the knee has a variable course. Symptoms can spontaneously worsen and also calm down.
- Swelling in the knee, especially after physical stress. This is called a synovitis.
Physical testing in knee osteoarthritis
The following physical tests may be performed for osteoarthritis-related symptoms
Pain on palpation of joint gap
The examiner palpates the entire joint gap. The test is positive when pain is felt with pressure on the joint crevice. Often a thickening of the bony structures of the knee is also felt.
Movement function examination of the knee
During this examination, the mobility in the knee is tested. The maximum extension and the maximum flexion of the knee joint are tested. Often we see in people with osteoarthritis a decrease in the mobility of the joint. Also, crepitations are often felt or heard.
Surgical intervention or conservative treatment
Surgical intervention: a new knee
Osteoarthritis of the knee does not mean that you immediately need surgery. But when the complaints only increase and the treatments no longer have the desired effect, a knee prosthesis or a new knee can offer a solution. This choice, however, is very much dependent on the individual. It really depends on the experienced pain and the experienced limitation in daily life. Together with an orthopedic surgeon the choice can be made to replace the knee.
Conservative treatment: counseling, exercise therapy, and adaptations to daily living
With conservative policies, the main focus is on how to make adjustments in daily life. An example of this is to start cycling more. Cycling is an unloaded movement. There is little pressure in the knee joint but you are still moving in a responsible manner. There is a structured exercise program where the muscles and other connective tissue around the knee are trained. Medication can possibly ensure that the irritation in the joint is reduced. If this is not enough, in consultation with the doctor a corticosteroid injection can be placed for a local pain relief effect.
X-ray of the knee
The different degrees of knee osteoarthritis
There are four grades of wear and tear on the knee, increasing in severity:
Grade I: The cartilage has softened and the springiness is reduced. Sometimes a single osteophyte (bone protrusion) is visible at the edges of the knee joint. This grade I damage is often undetectable on an X-ray.
Grade IIThere are cracks and irregularities in the surface of the cartilage. However, this damage is often superficial and does not yet extend to the bone. The cartilage layer has not yet been thinned by the wear and tear damage. Sometimes clear osteophytes are visible on X-rays. Also grade II lesions are not always detectable on an X-ray.
Grade III: The aforementioned tears have left deep grooves or holes in the cartilage. This damage extends deeper toward the bone, but the bone is often not exposed yet. However, a narrowed joint gap can sometimes be seen on the x-ray. Also, the edges of the bone ends are often affected.
Grade IV: In a grade IV lesion, the cartilage has (almost) completely disappeared and the underlying bone is exposed. The joint gap has narrowed and sometimes almost completely disappeared. Also, large bone protrusions have often formed and the ends of the bone parts are deformed.
Rehabilitation at Fysio Fitaal
Complaints from osteoarthritis in the knee can be very annoying. Osteoarthritis can of course not be eliminated. However, we can teach you to deal with your symptoms in a responsible manner. The therapists of Fysio Fitaal are specialized in the treatment and rehabilitation of osteoarthritis-related complaints. Our specialists will guide you as best as possible and motivate you where necessary. The combination of our extensive expertise in the field of orthopedic rehabilitation together with an extensive facility makes Fysio Fitaal the right place for you!