The free radial forearm flap is the most frequently used free flap for head and neck reconstructions. Survival of free flaps is dependent on adequate blood supply. A 69-year old woman was scheduled for excision of a T3N0M0 oropharyngeal carcinoma, neck dissections and reconstruction with a free vascularized radial forearm flap. During the operation it appeared that the entire radial artery was almost completely obstructed by atherosclerotic plaques precluding microvascular anastomosis. Despite systemic risk factors certain artery types are more prone to develop clinically manifest atherosclerosis. There are no reports on the pathology of the radial artery in free flap reconstructions. In head and neck cancer patients severe atherosclerosis of the radial artery is very rare, but if present makes free radial forearm flap reconstruction impossible. Therefore, in patients with risk factors for peripheral vascular disease screening for radial artery stenosis should be considered.