The elbow is a hinge joint composed of the humerus, ulna and radius bones. Cartilage surrounds the ends of bones to allow smooth gliding movements and shock absorption.
Ligaments are attached from bone to bone and allow stability of the joint. The elbow has the ulnar collateral ligament (UCL), the radial collateral ligament (RCL) and the annular ligament (holds the radial head in place).
Tendons are attached from muscles to bones. The largest tendons in the elbow are the triceps brachii, attached posterior (back) and the biceps brachii attached anterior (front).
Muscles that attach at the elbow allow for flexion, extension, supination and pronation movements. The large muscle groups that attach the outside of the elbow from the wrist are the extensor muscle group, the muscles that attach the inside are the flexor muscle group. The biceps muscle allows for flexion and the triceps allows for extension. Many of these muscles cross over the elbow to allow maximum support.
Nerves come from the spine and travel down extremities to allow sensory and muscular control. The ulnar nerve travels on the inside of the elbow (pinky side) and the radial on the outside of the elbow (thumb side).