Osteoarthritis, or degenerative arthritis, is the most common joint disease in humans, affecting 1 in 10 adults. While it can affect any of the joints in the body, osteoarthritis is most often found in weight-bearing joints such as the hip and knee.
Osteoarthritis in the knee is characterized by a gradual deterioration of the outer covering of the joint, called the cartilage. As the cartilage wears away, the underlying bone hardens, forming rough, bony spurs on the articular facet. In progressive osteoarthritis, the abnormal balance between the degree of cartilage deterioration and its ability to regenerate is disrupted. The cartilage softens, cracks and becomes fragmented. A chain reaction ensues, prompting the gradual breakdown of the cartilage and surrounding tissues, including bones, the synovial membrane, ligaments and menisci.
In very advanced stages of the disease, the cartilage is destroyed and the exposed bone cortex becomes thick and irregular due to wear. As the cartilage deteriorates, the joint space shrinks and becomes more pronounced most frequently, in the medial compartment of the knee. Radiologically, there is a narrowing of the medial tibiofemoral joint line and the patella also shows signs of wear.
How can you limit the extent of osteoarthritis?
Engage in regular physical activity
2. Previous injury to the joint
Maintain a healthy weight
3. Family history
Adopt proper posture at work and at home
6. Mechanical stress due to poor posture and/or repetitive tasks.
Signs and Symptoms
The main symptoms of knee osteoarthritis are pain and stiffness. This pain is often described as a dull pain that increases with use of the joint and diminishes with rest. In addition, cracking and popping noises may be heard and felt during movement. This may lead to a loss of joint mobility and function required for daily activities, leisure activities and sports.
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