One of the most common causes of knee tightness is a condition known as chondromalacia patella or "Runner's Knee," which arises from errors in the movement of the kneecap. The kneecap can slide off its normal track during movement if supporting muscles such as the quadriceps are too weak to cushion the impact. This greatly increases the risk of tightness for individuals involved in highly-strenuous physical activities, as the constant pressure fatigues leg muscles to a great degree. It is also possible to worsen Runner's Knee through inactivity. Other causes of knee tightness include joint inflammation, muscle cramps, and poor blood circulation.
Runner's Knee occurs when the kneecap slides off to either side, rather than smoothly over a groove located near the femur. This causes pressure to build up on the area surrounding the knee, making it difficult to move the joint. In addition, the friction created by the abnormal movement wears down the cartilage found underneath the kneecap, making it even harder to bend the knee. Misaligned or deformed joints can increase the risk of Runner's Knee.
Sitting in a position with knees bent a certain way can cut off circulation to the knee, aggravating the pain and tightness caused by Runner's Knee. Reduced circulation can lead to numbness in the knee or the sensation of swollen joints. These two symptoms can also cause the knee to feel tight, although they aren't indicative of any actual knee tightness.
Several conditions, such as rheumatoid arthritis, can cause inflammation in the knee. The increased pressure on the cartilage and ligaments can lead to both knee tightness and pain. Dehydration, on the other hand, can contribute to muscle cramps, which then make moving the knee difficult. Although the tightness is often limited to the muscles surrounding the joint, the sensation can sometimes extend to the knee itself.
Individuals can prevent tightness in the knee by developing strength and endurance in the muscle groups involved in knee bending and straightening. Regular leg exercises, such as jogging or cycling, can significantly reduce the risk of knee tightness. Improving the flexibility of these muscles can also help prevent Runner's Knee and cramps, making stretching an important routine before and after any form of strenuous physical activity. Individuals with poorly-formed joints or muscle deficiencies can choose to wear knee supports or orthopedic footwear to alleviate the strain on the knee. In cases of serious abnormalities, patients can opt for corrective surgery.