• The biceps brachii muscle produces flexion and supination of the elbow.
• The distal biceps tendon traverses through the antecubital fossa to insert on to the bicipital tuberosity
• Some of the superficial tendon fibers form the bicipital aponeurosis by passing over and blending with the fascia of the flexor-pronator.
• This structure is also referred to as the lacertus fibrosis.
• The distal biceps tendon comprises 2 components, one each from the long and short heads of the biceps muscle.
• The short head component is more superficial and inserts more distally.
A number of bursae have been described in the anticubital fossa.
The largest is the bicipitoradial bursa which surrounds the biceps tendon.
the smallest is between the radius and ulna called the bicipitoradial bursa.
This can become inflamed with repetitive pronation and supination.
In the typical position for elbow scanning, the distal biceps tendon is best evaluated on axial images.
In cases where the biceps tendon is under specific investigation, use of the FABS position can be helpful to show the tendon in long axis. In chronic disease, the biceps tendon may either appear:
thickened, fragmented or attenuated
with surrounding fluid in the sheath.
Cubital bursitis may be associated. The enlarged bursa contains the tendon distinguishing it from a tumour mass.
Rupture of the distal biceps tendon typically results from a sudden extension force applied with the elbow in 90 of flexion
May be seen in weight lifters and body builders, particularly if they are smokers or are taking anabolic steroids.
The report should note:
• Extent of retraction
• Presence of a remaining stump of tissue
• Involvement of the aponeurosis
The FABS MRI position useful to demonstrate distal biceps tears
The distal portion of biceps can be difficult to see on US
A useful technique to improve visualisation is:
• Place probe in transverse position over medial forearm at its mid point
• Move laterally keeping transverse until the radius is seen
• Rotate the probe approx 10-15 degrees counterclockwise for right arm, clockwise for left arm
• Flex the elbow 15-20 degrees
• Move the probe proximally and when brachial vessels come into view, the tendon will appear
• Rotate arm to confirm tendon in view is biceps (biceps moves, brachialis doesn’t)
