The intersection of the bones between your upper and lower leg form a complex support structure called the knee joint. Your knee joint allows you to bend and rotate your knee, enabling you to walk and run freely. Due to its frequent use, the knee joint is susceptible to injury and damage that can cause knee joint problems. Certain types of disease can also cause knee joint problems. If you experience symptoms associated with knee joint problems, speak with your doctor for further evaluations and care.
Arthritis
Arthritic and rheumatic diseases, such as rheumatoid arthritis or osteoarthritis, can cause knee problems to develop in some people. Rheumatoid arthritis can affect the membrane that lines the knee joint, while osteoarthritis can cause degradation of the knee joint cartilage. These diseases can cause inflammation, swelling and pain to develop within the knee joint, which can cause difficulty walking or moving about normally.
Meniscal Injuries
The menisci are two discs of connective tissue between the knee bones that protect and cushion the knee joint. Abnormal rotation of the knee can cause a partial or total tear of the meniscus. Symptoms of meniscal injuries include mild to severe pain within the knee, which is most notable when the knee is straightened. Swelling and inflammation of the knee joint can also occur, depending upon the extent of meniscal damage. If left untreated, the knee pain can become progressively worse and your knee may begin to lock, weaken or click during usual use. Symptoms of a meniscal injury can occur intermittently but typically persist until the damage is treated.
Ligament Sprains
Your knee contains four ligaments that strengthen and stabilize the bones of the knee joint: the medial and lateral collateral ligaments; and the anterior and posterior cruciate ligaments. A direct impact to the knee joint or abnormally twisting the knee can cause the ligaments to become stretched or torn, health professionals at the National Institute of Arthritis and Musculoskeletal and Skin Diseases explain. Such injuries are referred to as ligament sprains and can cause symptoms of knee joint swelling, pain and instability.
Tendon Injuries
Tendons are fibrous pieces of tissue that connect muscles to bones. If you injure a tendon within your knee, you can develop knee problems such as tendinitis or a ruptured tendon. Symptoms of knee tendon injuries include knee pain or tenderness; or difficulty bending or extending the leg. Painful knee symptoms due to tendon injuries are often most apparent while running or jumping.
Chondromalacia
Your patella (kneecap) is a small bone the helps protect the knee and provides leg muscles with necessary support. Leg muscle weakness, or overuse or injury to the kneecap can cause a condition called chondromalacia to develop. This condition is characterized be the softening of the kneecap cartilage. Symptoms of chondromalacia include dull, aching pain near or underneath the kneecap. Walking down a flight of stairs or straightening the knee can cause such symptoms to worsen if you have this condition.
