High incidence of posterior glenoid dysplasia of the shoulder in young baseball players.

Background: Rounding of the posterior glenoid rim is observed in young throwing athletes with internal shoulder impingement and is considered developmental dysplasia of the glenoid. The aim of our study was to determine the incidence rate of dysplastic changes of the glenoid within a group of 92 young baseball players.

Methods: The study group included 92 male baseball players, with a mean age of 14.