Knee Pain - Symptom Evaluation - Causes

Common causes of knee pain are:

• Osteoarthritis: Osteoarthritis is a condition that affects joints due to chronic wear and tear. The knee joint is commonly affected in osteoarthritis. The patient complains of pain, joint swelling and eventually decreased range of motion. It usually occurs in older and/or overweight individuals, though it can occur in younger individuals who have suffered from knee trauma. It is diagnosed using x-ray of the joint.

• Rheumatoid arthritis: Rheumatoid arthritis is an autoimmune condition where the patient’s body produces certain proteins that attack the joints. Rheumatoid arthritis causes pain and warmth in the joint, joint swelling, morning stiffness and decreased range of motion. The small joints of the hands and feet are usually affected first. Joints are affected symmetrically on both sides of the body.
• Other autoimmune conditions: Other autoimmune conditions like systemic lupus erythematosus (SLE), psoriasis can also affect the knee joint. Other symptoms associated with the conditions like skin lesions are often obvious, thereby supporting the diagnosis.
• Gout: Gout is a condition that is caused by increased uric acid levels in the blood. Gout causes arthritis; the most commonly affected joint is the big toe. The knee can also be affected resulting in pain, swelling and redness in the joint. The joint is sometimes so sensitive that even a slight touch can cause pain. Blood and joint fluid testing for uric acid can help to diagnose the condition.
• Reactive arthritis: Reactive arthritis occurs following an infection usually of the urogenital or the intestinal tract. Three symptoms are commonly associated with reactive arthritis – conjunctivitis, urethritis and arthritis.
• Chondromalacia: Chondromalacia is a condition where there is softening of the cartilage surface of the patella. It is more common in athletes like runners and cyclists. The patient experiences a dull pain around the patella, which worsens on moving down a slope or stairs, and sometimes while climbing up. X-ray or arthroscopy help to confirm the condition.
• Injuries: Injuries of structures in the knee can result in knee pain. Some of these injuries include:
• Meniscal tear: A tear in either the medial or lateral meniscus may result from a twisting injury. The patient complains of pain while straightening the leg, locking, clicking or giving way of the knee, and swelling. MRI or arthroscopy may be used to confirm the diagnosis.
• Cruciate ligament tears: Tears of the cruciate ligament may result in some pain, instability of the knee joint and tendency to buckle under. MRI or arthroscopy may be used to confirm the diagnosis.
• Medial and lateral collateral ligaments injuries: Injuries to the medial and lateral collateral ligaments often occur during contact sports. Symptoms include pain, swelling and instability of the joint. Diagnosis is with MRI.
• Patellar tendon injuries: Inflammation or rupture of the patellar tendon may be due to frequent injuries. It results in severe pain, swelling and an inability to move the leg at the knee joint. Diagnosis is through physical examination and MRI.
• Infections: Some bacterial and viral infections can also cause knee pain. Bacterial infection of the knee joint causes pain, swelling and redness of the joint with fever. Chikungunya is a viral infection associated with fever and severe pain in joints including the knee joint.