The observation of eight patients with lesions of great arteries after total hip replacement led to experimental investigations to determine whether Palacos might cause such vessel lesions. Palacos was applied to the adventitia of the abdominal aorta and both iliac arteries in rabbits. Angiographic examinations 14 days after implantation indicated no lesion at the intima of aorta and iliac arteries in the regio of Palacos. Histological investigations showed only necrosis of fat tissue and a slight distention of the muscle fibers of the artery wall. Lesions of aorta or great arteries are not caused by implantation of Palacos.