Imaging description

The diagnosis of SLAP (superior labral anteroposterior) lesions is based on abnormalities in signal intensity and morphology. MR imaging findings reported to be characteristics of SLAP lesions include increased signal intensity in the labrum, with or without extension to the biceps anchor, and cleavage of the superior labrum (Figure 3.1). Pseudo-SLAP is a small sulcus between the superior labrum and the origins of the biceps tendon. It is a small contrast-filled sulcus with variable depth observed on oblique coronal MR images (Figure 3.2).

Importance

Pitfalls in standard MR imaging are related to the presence of increased intralabral signal intensity without surface irregularity or definite labral tear.

Typical clinical scenario

The majority of patients present with concurrent shoulder injuries.

Differential diagnosis

A deep sulcus between the superior labrum and the biceps tendon may simulate a SLAP lesion. Increased intralabral signal intensity is a common finding and may be associated with magic angle phenomena or intrasubstance labral degeneration. Partial volume averaging with the glenohumeral ligaments is also a common finding.

Teaching point

Careful evaluation of the whole extension of structures usually allows differentiation of a normal structure from a tear.