Osteoarthritis of the knee

It is the result of the wear and progressive loss of articular cartilage that can ultimately lead to limiting disability over time, although the rate of progression varies for each individual. It is the most commonly diagnosed type of arthritis, with an annual incidence of 240 cases per 100,000, but it continues to increase as life expectancy and obesity rise.

Knee osteoarthritis is the result of the degeneration of articular cartilage, for which the cause is currently unknown. It is commonly thought to be due to age-related wear and tear, but also to the condition of the disease itself, as there are differences in the cartilage of osteoarthritis compared to normal aging. Additionally, there is an increased expression of enzymes responsible for cartilage degradation in knee osteoarthritis compared to normal values in healthy aging.

However, in addition to a hereditary tendency to develop osteoarthritis, or certain hereditary traits such as having bowed legs, knock knees, or joint laxity, there are several additional factors that can contribute to a higher risk of developing knee osteoarthritis:

• Age: the risk increases with advancing years, although it usually appears from the age of 40.
• Gender: women are more prone to it, although the reason is unknown.
• Overweight or obesity: a body mass index (BMI) of 30 or higher is a significant risk factor, increasing the likelihood of developing knee osteoarthritis by up to 7 times due to the added stress on the joints. Additionally, adipose tissue produces proteins that can cause inflammation in and around the joints.
• Knee injuries, joint deviations, or deformities.
• Frequent overload on the knee in a work or sports context.
• Diseases: gout, rheumatoid arthritis, metabolic disorders such as hemochromatosis from iron deposition in the joints, or defects in growth hormone overproduction can increase the risk of developing this disease.

The symptoms of osteoarthritis often develop slowly and worsen over time. Pain is the most common symptom of knee osteoarthritis, both during movement and at rest. Additionally, other possible symptoms that may occur include:

• Stiffness, locking, or tenderness of the joint, especially after a long period of immobility.
• Loss of flexibility in the joint.
• Swelling, warmth, or inflammation of the knee.
• Presence of hard lumps (osteophytes) around the joint.
• Cracking or popping sounds during movement.
• Weakness of the joint when standing.

Although knee osteoarthritis cannot always be prevented, there are measures that can help reduce the risk of developing it:

• Maintain a healthy weight.
• Rest and aim for a restorative sleep of at least 6-8 hours each day.
• Incorporate strength exercises as much as possible to strengthen the muscles in the area and reduce wear on the joint itself.
• Limit the impact of physical exercise on the knee by engaging in activities like swimming or cycling, and if running, do so on grass or soft surfaces, avoiding hard surfaces.