Glenolabral Articular Disruption (GLAD)

Excerpt

A glenolabral articular disruption (GLAD) lesion is a specific sub-type of a soft tissue shoulder injury (see Image. Magnetic Resonance Angiography, Axial GLAD Lesion). It involves a combination of a superficial tear to the anterior-inferior labrum and damage to the adjacent articular cartilage on the glenoid. The labrum is the fibrocartilaginous ring surrounding the glenoid fossa.

The GLAD superficial labral tear pattern, with the deep fibers still intact, means that the labrum is not grossly unstable. Therefore pain rather than frank instability symptoms should be present. The extent and type of underlying damage to the glenoid cartilage vary; it can be anything from more minor fibrillation to complete cartilage loss.

Since Neviaser first reported it as a limited series in 1993, it is now recognized as an uncommon but well-established cause of shoulder pain following trauma. The original observations were that the mechanism usually involves a fall with forced adduction movement to the abducted and externally rotated shoulder, but two cases were related to throwing activities. There may also be a subluxation or dislocation injury associated. Since Neviaser reported the original series, it is apparent that sometimes the term may be used more loosely to describe any combined labral pathology and adjacent articular cartilage lesion.

Clinical examination findings may be non-specific, including anteriorly sited or generalized shoulder pain during abduction and external rotation of the joint. Historically, GLAD lesions have been identified as being associated with a stable glenohumeral joint. As such, patients would reportedly display a full range of movement on examination without evidence of apprehension or subluxation.

More recently, however, several reports have described GLAD lesions in the context of either isolated or recurrent dislocations, and thus the stability of the joint is not necessarily regarded as a distinguishing examination finding. The indistinct findings on examination make a clinical diagnosis of the lesion challenging, and imaging is required to confirm its presence.