[Chronic instability and fixed dislocation of the shoulder]

Chronic instabilities may be traumatic or atraumatic, unidirectional or multidirectional. It is important to distinguish between symptomatic instability and asymptomatic hyperlaxity. Posttraumatic, unidirectional anterior instability without hyperlaxity is the most common form of instability. The patient presents apprehension, the sulcus-sign is negative. Posttraumatic, unidirectional instability with hyperlaxity is due to an adequate trauma, both the apprehension test and the sulcus sign are positive. The treatment of traumatic instability is surgically with respect to the underlying pathology of the ligaments, labrum and capsule. The "golden standard" is the reconstruction of the capsulolabral complex. The repetitive microtraumatic instability is seen in overhead athletes with elongation or disruption of the capsule. The typical patient presents with painful subluxations, the instability may be unidirectional or multidirectional. The treatment is conservatively. Multidirectional instability with hyperlaxity is defined as symptomatic instability in at least two directions of instability with multidimensional hyperlaxity. These individuals will also report on pain rather than instability. The apprehension test is positive in at least two directions, the sulcus sign is positive as well. The patients are responsive to an intensive rehabilitation program for 6-12 months. Open capsular shift or thermal capsular shrinkage may be successful after failed conservative treatment. Multidirectional instability without hyperlaxity is extremely rare and is due to more than one adequate trauma with traumatic instability in different directions. The apprehension test is positive, the sulcus sign negative. The treatment is surgically. The fixed dislocation is posterior in most of the cases and frequently being missed primarily. It is seen in unconscious, multiple-injured patients or after grand mal or electroshock seizures. The reduction may be either closed or open depending on the interval between trauma and diagnosis. Voluntary instability represents a subset of individuals with atraumatic instability. The patients can dislocate and reduce their shoulder, have no pain and do not develop arthritis. They do not require a special therapy.