Spectrum of Injury to Posterior Glenoid Labral Complex With Emphasis on Diffuse Labral Tears

The posterior glenoid labrum has numerous surrounding structures and any of them can undergo derangement. It is prudent to consider the posterior glenoid labrum complex (PGLC) as a whole rather than simply the labral tissue in isolation when evaluating magnetic resonance imaging (MRI) of the shoulder. The PGLC contains the posterior capsulolabral junction, posterior capsule (posteroinferiorly , the posterior band of the inferior glenohumeral ligament), posterior chondro-osseous junction, posterior chondrolabral junction, posterior glenoid bone, posterior glenoid subchondral bone, posterior glenoid cartilage, posterior labrum, synovial fold (variably seen), and posterior glenoid periosteum (or periosteal sleeve). Noninvasive MRI techniques are the mainstay in evaluating PGLC injury with or without the use of intra-articular gadolinium contrast agents. When using the PGLC model, a spectrum of pathology can be stratified.