Five patients presented with classic symptoms diagnostic of intermittent claudication that were exacerbated by strenuous activity. Examination demonstrated localized tenderness over the lacertus fibrosus (bicipital aponeurosis), as well as increased pain and an obliterated radial pulse with forearm pronation and resisted elbow flexion. All 5 were athletes who had hypertrophied forearm muscles. Patients were diagnosed with brachial artery compression by the lacertus fibrosus. Release of the lacertus fibrosus restored normal pulses in all cases. Followup ranged from 6 months to 25 years. Full clinical recovery was achieved in 3 patients. One patient had a good result and 1 a fair result. Although the lacertus fibrosus has been well described as a cause of neural compression and compartment syndrome, it has been reported only once to cause intermittent arterial compromise. Hypertrophy of the muscles and the lacertus fibrosus related to excessive use is an important factor in the development of isolated vascular, neural, or combined neurovascular lesions.