Instabilidade multidirecional do ombro / Multilateral instability of the shoulder

RESUMO

Multidirectional instability, first described by Neer and Foster in 1980, still remains a not well-known condition and its etiology not clear. It is a complex entity and its pathophysiology is not very clear. However, an increased capsular volume that extends in the inferior, anterior, and posterior directions is always found, the rotator interval playing a role as a defect or an insubstantial attenuated tissue. This capsular laxity increases the glenohumeral translation in more than one direction when the capsular ligaments restraints fail. As the contralateral side has the same findings and most of the time remains stable, other factors besides the laxity seem to take part in the pathophysiology. The rotator cuff has a stabilizing effect as the scapulothoracic motion acts as a platform for the humeral head during active arm abduction. Some authors showed that patients with multidirectional instability have deficits in shoulder proprioception. Because of this, there is a agreement that treatment of this entity should begin with a rehabilitation program to improve the rotator cuff unit, scapular stabilizers, neuromuscular coordination, and proprioception of the glenohumeral joint. After six months, if the shoulder remains unstable, the patient becomes a candidate for surgical treatment. Capsular shift is the procedure of choice and nowadays it can be performed in three different ways open,arthroscopically, or thermal shrink-age.