Fig. 14. Glenohumeral dysplasia in two neonates.

Follow-up shoulder imaging in a 13-month-old child with clinically suspected brachial plexus palsy at birth (a-c). He subsequently developed glenohumeral dysplasia. The right humeral head is small, glenoid is shallow as seen on the radiograph (a); compare with the normally formed left humeral head and glenoid labrum (b). Axial T1 MR image (c) reveals posterior subluxation of humeral head; compare to normally aligned left humeral head (d). 2-month-old with history of right brachial plexus injury post-delivery (e-g). Ultrasound images from two exams performed 1 month apart (e and f) demonstrate progressive right glenohumeral dysplasia with interval increase in right humeral alpha angle from 33 degrees to 60 degrees. Axial DESS image from a follow-up MR exam (g) shows a shallow right glenoid with posterior humeral head subluxation. Normal left glenohumeral joint