How does the elbow work and what causes pain?
The elbow is the joint where three long bones meet in the middle portion of the arm. The bone of the upper arm (humerus) meets the inner bone of the forearm (ulna) and the outer bone of the forearm (radius) to form a hinge joint. The radius and ulna also meet in the elbow to allow for rotation of the forearm. The elbow functions to move the arm like a hinge (forwards and backwards) and in rotation (twisting outwards and inwards). The biceps muscle is the major muscle that flexes the elbow hinge. The triceps muscle is the major muscle that extends the elbow hinge. The outer bone of the elbow is referred to as the lateral epicondyle and is a part of the humerus bone. Tendons attached to this area can be injured, causing inflammation or tendinitis (lateral epicondylitis, or "tennis elbow"). The inner portion of the elbow is a bony prominence called the medial epicondyle. Additional tendons from the muscles attach here and can be injured, causing medial epicondylitis ("golfer's elbow"). A fluid-filled sac (bursa), which serves to reduce friction, overlies the tip of the elbow (olecranon bursa). The elbow can be affected by inflammation of the tendons or the bursae (plural for bursa), or conditions that affect the bones and joints, such as fractures, arthritis or nerve irritation.
The elbow may be subject to either a fracture or sprain. Arthritis is also common in the elbow, as with all joints.
The bones of the elbow can break (fracture) into the elbow joint or adjacent to the elbow joint. Fractures generally require immobilisation and casts and can require orthopaedic pinning or open joint surgery.
A sprain is a stretch or tear injury to a ligament. One or more ligaments can be injured during a sprain. This might occur when the elbow is hyperextended or simply jammed, such as in a "stiff arm" collision. The severity of the injury will depend on the extent of injury to a single ligament (whether the tear is partial or complete) and the number of ligaments involved. Treatment involves rest, ice, immobilisation, compression, and anti-inflammation medications.
Arthritis of the elbow
Inflammation of the elbow joint (arthritis) can occur as a result of many systemic forms of arthritis, including rheumatoid arthritis, gouty arthritis psoriatic arthritis, ankylosing spondylitis and reactive arthritis (also called Reiter's disease). Generally, they are associated with signs of inflammation of the elbow joint, including heat, warmth, swelling, pain, tenderness and decreased range of motion. Range of motion of the elbow is decreased with arthritis of the elbow because the swollen joint impedes the range of motion.