This condition is a compression injury to the ulnar nerve near the elbow. This is the nerve that produces a jolt when you bump your "funny bone."

This condition is a blood clot that forms in a vein deep inside the body. This type of clot most commonly develops in the legs. This condition is dangerous, because the clot can break free and travel through the bloodstream to the lungs.

This condition is an inflammation of the olecranon bursa, a fluid-filled sac between the skin and bones on the back of the elbow. It can cause pain and restrict motion of the elbow. The bursa may also become infected.

If your hip joint hurts, or if it catches or clicks when you move your leg, you may have a torn labrum. That's a rim of tissue that surrounds the hip's socket. It helps to deepen the socket and cushion the joint. A torn labrum can keep the hip joint from working smoothly.

This condition, commonly called tennis elbow, is an inflammation of the tendons that connect the muscles of the forearm to the elbow. The pain is primarily felt at the lateral epicondyle, the bony bump on the outer side of the elbow.

This is a common injury of the knee. Your knee joint is cushioned by two c-shaped wedges of cartilage called the "menisci." Each individual cushion is called a "meniscus." This injury is a tear of one of these cushions.