Management of elbow instability in adults

The elbow joint is responsible for positioning the hand into a huge volume of space due to the movements performed around it (flexion, extension, supination and pronation). The stability of this joint is important to perform these functions. This stability depends on its anatomical structures whether the bony structures or the soft tissues around it (1).The elbow joint consists of three separate bony articulations together inside a small capsule. It has been called the trochleogingylomoid joint for the hinged (ginglymoid) motion in flexion and extension at the ulnohumeral and radiocapitellar articulations and radial (trochoid) motion in pronation and supination at the proximal radioulnar joint (4). Stability of the elbow is provided by a ‘‘fortress’’ of static and dynamic constraints (5). The three primary static constraints include the ulnohumeral articulation, the anterior bundle of the medial collateral ligament (MCL), and the lateral collateral ligament (LCL) complex specially the ulnar part of it. If these three structures are intact, the elbow is stable. Secondary constraints include the radiocapitellar articulation, the common flexor tendon, the common extensor tendon, and the capsule. Muscles that cross the elbow joint are the dynamic stabilizers (6).Elbow instability is a general term used to describe anything from a dislocation of the ulnohumeral joint to clinically important injury of the varus and/or valgus stabilizers of the elbow, and the radial head. The instability of the elbow joint can be classified into acute and chronic instability (2)..