What is a stiff knee?
A stiff knee occurs when you have difficulty moving the knee joint due to injury to or inflammation of the joint. Anything that leads to restricted movement of the knee joint may be considered to cause stiffness of the knee.
Four ligaments are important in maintaining the stability and function of the knee joint, the anterior and posterior cruciate ligaments, and the medial and lateral collateral ligaments. The menisci are two pieces of cartilage that permit the bones of the knee joint to move smoothly against one another. Injuries to these structures may restrict movement of the knee joint.
Other traumatic causes of stiff knee include fractures of bone, inflammation of tendons or bursae, or damage to the cartilage of the kneecap. Injuries may be sudden or may develop slowly over time.
The different forms of arthritis are the most common chronic diseases to affect the knee. Osteoarthritis results from wear and tear on the joint, while rheumatoid arthritis (chronic autoimmune disease characterized by joint inflammation) arises from a dysfunction of the body’s immune system. Rarely, tumors and infections of the knee joint and surrounding areas may produce a stiff knee.
A knee injury can require emergency care, and a sprain may be accompanied by more serious injuries to the joint. Seek immediate medical care (call 911) for serious symptoms, such as paralysis, loss of sensation, absent pulses in the feet, complete inability to move the knee joint, high fever (higher than 101 degrees Fahrenheit), severe bleeding, or uncontrollable pain.
If your stiff knee is persistent or causes you concern, seek prompt medical care.
SYMPTOMS
What other symptoms might occur with a stiff knee?
Stiff knee may accompany other symptoms, which vary depending on the underlying disease, disorder or condition. Conditions that cause stiff knee may also lead to symptoms in other body systems....
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CAUSES
What causes a stiff knee?
A stiff knee is most commonly caused by an injury to the knee or by an inflammatory process, such as arthritis in the knee joint....
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