The J sign refers to the appearance of the inferior glenohumeral ligament in the presence of a humeral avulsion of the glenohumeral ligament (HAGL lesion). The normal U-shaped inferior glenohumeral recess is retracted away from the humerus, appearing as a J (right shoulder).
- 1. Carlson Christian L. “The “J” Sign1.” Radiology 232, no. 3 (2004): 725-726. doi:10.1148/radiol.2323021239.