The Functional Complex

The functional anatomy of the elbow joint complex is unique in orientation and configuration. Three bones, the ulna, radius, and humerus, articulate to form four articulations: the humeroulnar, humeroradial, superior radioulnar, and inferior radioulnar joints. This unique osseous structure provides the elbow excellent static stabilization, which is enhanced by the ulnar collateral ligament, the lateral collateral ligament, and the elbow joint capsule. Twenty-three muscles are directly associated with the elbow joint and can be classified into four main groups: the elbow flexors and extensors and the flexor-pronator and extensor-supinator groups. These muscles provide dynamic stabilization to the elbow and enable the hand to perform skilled, precise motions. The purpose of this review article is to provide the clinician with an understanding of the unique anatomy at the elbow joint and to enhance the clinician's knowledge of the biomechanics, clinical examination, and rehabilitation of the elbow complex.