[Traumatic posterior dislocation of the shoulder in adults. Apropos of 25 cases]

In a series of 25 traumatic posterior dislocations of the shoulder treated from 1960 to 1985, 16 were overlooked and the time from injury to treatment ranged from 3 weeks to 14 months. 11 cases were secondary to motor vehicle accident and 14 occurred after a convulsive fit. Early closed reduction was effective in only 4 cases; in 2 cases, reduction was unstable and further screwing of an associated fracture of the tuberculum majus was performed to prevent redislocation; 3 locked dislocations necessitated open reduction and stabilization by subscapularis transposition into the defect of the humeral head. Most of the 16 chronic unreduced dislocations were treated by the same procedure. Overall, 21 cases were reviewed with a mean follow-up of 14 years. Functional outcome was more often satisfactory in acute (5/7) than in old unreduced dislocations (6/14). Mc Laughlin or Neer's procedures yielded good results in 9 out of 14 cases; they are indicated irrespective of the patient's age whenever Mc Laughlin's notch does not involve more than one third of the articular surface of the humeral head.