Knee Pain: Causes, Signs, Symptoms, Diagnosis and Treatment, When To See Your Doctor?

Autoimmune arthritis

• Several autoimmune diseases including rheumatoid arthritis, systemic lupus and ankylosing spondylitis can involve the knee joint, causing pain and immobility. These conditions commonly affect other joints and may affect other body systems as well such as the cardiovascular, respiratory or urinary systems.
• Joint infection: Joint infection is rare, since the knee joint is separated from the surroundings by tough tissue and capsule, but if these natural defenses are breached, as in case of penetrating trauma, severe infection can occur. Joint infection needs rapid identification and treatment, or rapid joint destruction can occur.
• Bone fracture: Bones forming the knee joint are the thigh bone (femur) and the shin bone (tibia). Both of those bones are strong, but they are subject to injury and fractures can occur. Tibial plateau fractures are more common and can cause severe pain and bruising of the knee joint.
• Gout: Gout is the accumulation of uric acid crystals -which originate from the metabolism of proteins- in the capsule of a joint. This condition is known as gouty arthritis, and commonly affects smaller joints like those of the toes and fingers. However, the knee joint can be affected in severe cases. It commonly occurs in the form of recurrent attacks of incapacitating pain following meals that contain red meat or in heavy coffee and tea drinkers.
• Bone cancer: Bone cancer is a rare cause of joint pain. It commonly affects children and young adults and is very rare after 30 years old. Classical symptoms include bone pain around the knee joint with the presence of a hard swelling and overlying redness and tenderness.