Superior labrum anterior to posterior lesions: Part 1 - Imaging and anatomy with arthroscopic classification

The glenoid labrum deepens the glenoid fossa and allows for the attachment of the long head of the biceps tendon and the glenohumeral ligaments, contributing to the stability of the glenohumeral joint. The superior labrum is a common site of labral injury, especially in athletic activities involving overhead activity. The acronym SLAP (superior labrum anterior to posterior or anteroposterior) lesion was introduced by Snyder and colleagues in 1990 to describe superior labral tears. The article will review the optimal technique to image the glenoid labrum, covering normal labral anatomy with special emphasis on the anatomic variants of the labrum that can be mistaken for SLAP tears by means of colour illustrations, magnetic resonance imaging and correlative arthroscopy images.Contribution: The illustrated review functions as a crucial radiological guide for both radiologists and orthopaedic surgeons. The combination of illustrations, MR and correlative arthroscopic images enhances the comprehension of normal labral anatomy and its variants. The review underscores the significance of understanding anatomic variations that may be misinterpreted as pathology. This understanding is vital in guiding orthopaedic management for patients, ensuring appropriate treatment strategies.