This paper might have been more accurately entitled "An Unusual Complication of the Twist," for it was shortly after doing "the twist" that the patient began to complain of pain in the popliteal fossa.
Arterial aneurysms of the lower extremity occur infrequently. Mills, at the Mayo Clinic, reported an incidence of only 3.5% in 396 cases of aneurysms.1 Even so, the popliteal artery is the vessel most commonly the site of peripheral aneurysm formation.2 The commonest etiologic factor in such aneurysms is arteriosclerosis.3 In 100 cases reviewed by Gifford, Hines, and Janes,4 32 cases were associated with arteriosclerosis, 3 with syphilis, 1 with mycotic infection, and 1 with trauma. No case of popliteal aneurysm associated with osteochondroma or exostosis of the femur was reported by this group of investigators. Brailsford,5 in his radiology textbook, makes references to a case; however, a detailed case report does