We report a case of a 56-year-old man who sustained a ruptured long head of biceps tendon (LHBT) that presented with symptoms typical of a pectoralis major rupture. Magnetic resonance imaging revealed an isolated LHBT tear. Intraoperatively, the biceps tendon had an unusually thick distal segment entrapped under the insertion of the pectoralis major. Surgery led to an excellent outcome.
A ruptured LHBT with an associated large distal segment producing a mass effect on the pectoralis major can mimic a pectoralis major rupture and may ultimately require surgery to alleviate symptoms.