The elbow joint is a synovial hinge joint, similar to the ankle and knee joints. Two or more bones form hinge joints that move along an axis, rather than rotate like the hip joint. The distal humerus and proximal ulna are the primary elbow joint bones. In addition, the hinge joint allows the elbow to bend and straighten. It also helps with hand motion by allowing the forearm to rotate.
The elbow consists of three articulations, which are:
- The ulnohumeral joint.
- The radioumeral joint.
- The proximal radioulnar joint.
Lateral elbow pain is referred to as pain located on the outside of the elbow joint. There are a wide variety of conditions that are associated with this symptom, especially one known as lateral epicondylitis (“tennis elbow”). Tennis elbow is a painful overuse injury affecting the tendons that connect the muscles controlling the wrist and fingers to a bony protrusion on the elbow called the lateral epicondyle. These tendons are involved with motions of the arm that bend or twist the wrist.
The other conditions that accompany lateral elbow pain include:
- Radial tunnel syndrome – This is also known as radial nerve entrapment or posterior interosseous nerve entrapment. It occurs when the radial nerve in the arm becomes compressed or restricted in the tunnel it passes through. Pain on the outside of the elbow is one of the symptoms associated with this condition.
- Radiohumeral bursitis – Radiohumeral bursitis is an inflammation of a bursa or small sack of fluid that sits between the tendon and the bone. It has similar symptoms to tennis elbow which includes pain, tenderness, and a limited range of movement in the elbow.
- Osteochondritis dissecans in the elbow joint – Osteochondritis dissecans is a fragmentation of the cartilage and sometimes the underlying bone that lines the ends of bones in the elbow joint. This condition is common in adolescents as the ends of the bones are not yet fully hardened.
- Synovitis – Synovitis of the elbow joint is inflammation of the synovial membrane which surrounds the joint. Symptoms include elbow joint pain and redness over the area. However, synovitis is normally caused by another condition, including an injury to the joint or an illness like cancer. Because of this, synovitis may indicate a serious problem.