Knee pain can be caused by injury to tendons, ligaments or cartilage in the knee area. Arthritis, gout, bone and joint problems can also cause knee pain. Ligament injury is characterized by immediate pain and a popping sound.

The person will be unable to bear weight on the affected leg. Injury and inflammation of the tendon is characterized by sharp pain, swelling and an inability to flex the leg. Sometimes the cartilage in between bones wears away, resulting in the bones rubbing against each other. This happens in case of arthritis and the patient feels crunching or grinding sensation while walking. In some cases, cartilage like the meniscus can curve and wedge within the bones of the knee joint. This results in swelling and locking of the knee.

 The person is unable to bend or stretch the knee due to locking. Knee pain can also be associated with bursitis, inflammation of the bursa or small sac which holds the lubricating fluid for the knee joints. Bursitis is characterized by fever, pain and swelling. Dislocated kneecaps which occur due to injury or impact are characterized by intense knee pain, excessive movement of the knee cap, swelling and stiffness. In general, pain, swelling, stiffness, knees giving way etc are the characteristic symptoms of knee pain.