Popeye’s sign, a hallmark of biceps tendon rupture.
The biceps brachii muscle primarily functions as a forearm supinator. The muscle is formed by a long and short head that share a distal tendon attachment site, but have distinct proximal tendon attachment sites on the scapula.
Rupture of the biceps tendon can occur at either the proximal or distal sites, although distal rupture is rare. The mechanism of injury can range from degenerative changes in the elderly to athletic injuries related to weight lifting or throwing in younger patients. Trauma at any age can result in a biceps tendon rupture, and these injuries are often associated with a ‘popping’ sound.
Clinical manifestations of ruptures often include a sudden onset of sharp shoulder pain, ecchymosis, and swelling. In patients with chronic shoulder pain, however, an acute rupture may improve pain quality. As noted in acute tendon rupture is classically associated with the ‘Popeye’ deformity, a visible or palpable mass present near the elbow or in the mid-upper arm.
Diagnosis of a biceps tendon rupture is primarily made by history, inspection, and palpation. Imaging modalities such as MRI or ultrasound may be helpful to delineate a complete versus partial rupture but are otherwise unnecessary to make a diagnosis.
Treatment: There are no consensus guidelines on the indication for surgical repair, although distal ruptures seem to have greater clinical benefit from repair as these patients have significant defects on their physical examination. Chronic tears become increasingly more challenging to treat due to possible tendon contraction and poor tissue quality but tendon grafts have been successfully used for these cases. Active patients who depend on arm strength, such as athletes, may be appropriate candidates for surgical referral.