LOCALIZED GLENOID HYPOPLASIA - AN ANATOMIC VARIATION OF POSSIBLE CLINICAL-SIGNIFICANCE

Examinations were done on 1150 scapular hone specimens from museum col lections, A localized hypoplasia of the posteroinferior glenoid was fo und in significant numbers (20%-35%) depending on the population group studied, Criteria were established for the identification of this var iant in computed tomography and magnetic resonance studies, Localized hypoplasia of the posteroinferior glenoid was detected as an incidenta l finding in 54 (18%) of 300 such studies. Using these same imaging cr iteria in a prospective manner, 9 of 12 patients seen for voluntary mu ltidirectional instability of the shoulder displayed a localized poste roinferior glenoid hypoplasia, This phenomenon also may add to the pic ture of extreme posterior glenoid wear that sometimes is seen in assoc iation with osteoarthritis of the shoulder.