Erecta dislocation of the shoulder - a rare entity

Inferior shoulder dislocation, Erécta dislocation or mast dislocation of the shoulder is a rare and unusual form of shoulder dislocation, with an estimated incidence of 0.5% of all dislocations. We present a case of inferior dislocation in a 65-year-old patient, occurring following an MVA with the upper limb in extreme abduction, external rotation and elbow flexed. Radiography confirmed the diagnosis. Reduction was performed under general anaesthesia using gentle traction in the axis. Davids and Talbott reported two mechanisms of Luxatio Erecta. The first is an indirect mechanism following forced abduction of an already abducted limb, so that the diaphysis is at a higher level than the acromion. The second mechanism is direct trauma following axial loading on an already abducted limb. Two methods of reduction have been described in the literature. The first, which is the one used for our patient, consists of a traction-countertraction. The second is a small rotation of the humeral head, aimed at transforming the dislocation into its anterior variety, then reducing it by one of the methods described above.