Posterior shoulder dislocations are diagnosed rarely in every-day practice. Although the methods of radiological imaging have been developing and becoming commonly available, the cases of late diagnosis are still happening. Proper clinical examination and properly conducted and interpretated radiographs allow for identification and implementation of appropriate medical procedures. In spite of fact that such cases are identified expectionally rarely, a few types of procedural have been analised and numerous therapeutic methods have been described. The choice of an appropriate treatment is complicated and requires in-depth theoretical knowledge as well as the knowledge of specific conditions within the shoulder surgery. Based on an algorithm, proposed by Griggs, between 2000-2006 seven patients with locked posterior instability were treated, for all of them defect of the proximal humerus did not exceed 30%. In all these cases the goals of improving stability and range of motion were obtained.