MR Arthrography of Rotator Interval, Long Head of the Biceps Brachii, and Biceps Pulley of the Shoulder

Abstract

The rotator interval and the long head of the biceps brachii tendon are anatomically closely associated structures believed to confer stability to the shoulder joint. Abnormalities of the rotator interval may be acquired or congenital and are associated with instability of the long head of the biceps brachii tendon. Clinical and arthroscopic diagnoses of rotator interval abnormalities and subtle instability patterns of the long head of the biceps brachii tendon are difficult. Magnetic resonance arthrography, owing to its superior depiction of ligaments with distention of the joint capsule, may be the procedure of choice, barring open surgery, for help in diagnosis of these conditions.

Imaging of Shoulder Injuries in Sports Medicine: Current Protocols and Concepts

“…49 Rotator interval capsular injuries on MRI and MRI arthrography manifest as thickening, irregularity, or disruption of the capsule. 48 Gadolinium touching the tip of the coracoid process on the sagittal images has been associated with surgically confirmed interval lesions. 51 Interval lesions may also be suggested based on indistinctness or thickening of the coracohumeral and superior glenohumeral ligaments.…”

“…48 The rotator interval encompasses the rotator interval capsule, long head of the biceps tendon, and the structures of the biceps pulley (superior glenohumeral ligament, coracohumeral ligament, and superior leading edge of the subscapularis tendon). Rotator interval lesions in athletic patients may be thought of as either involving the rotator interval capsule or biceps pulley.…”

“…22 Detection is important, because patients with rotator interval capsular injuries may benefit from open surgical repair. 48 The biceps pulley stabilizes the long head of the Imaging of Shoulder Injuries biceps tendon through its intra-articular course. Injuries to the components of the biceps pulley may result in biceps subluxation or dislocation.…”

“…Injuries to the components of the biceps pulley may result in biceps subluxation or dislocation. 48 The biceps tendon may be displaced superficial to, deep to, or within the substance of the subscapularis tendon. The latter is referred to as the hidden lesion because it may be unapparent at arthroscopy; hence the value of imaging.…”

“…Missed interval lesions may be a potential cause of failed instability surgery. MRI arthrography is the imaging study of choice for evaluation of the rotator interval, 48 with the oblique sagittal plane being the preferred plane for evaluation (Fig. 27).…”