A case of repeated occlusion in the common iliac artery due to an unexpected stent deformation.

We report a case experiencing repeated common iliac artery (CIA) occlusion due to an unexpected stent deformation. A 74-year-old man with intermittent claudication had undergone balloon-expandable stenting for the left CIA. Six years after his first stent implantation, his left CIA was totally occluded inside the stent. We performed revascularization for the left CIA and achieved sufficient balloon inflation and balloon-expandable stenting. Then, one and a half years later, his left CIA was re-occluded. CT angiography showed compression by the protruding hyperostotic lumbar vertebral body, such that both stents had become deformed into a crescent shape. We were told that he had been using a powerful massage machine to stretch and relieve his spondylotic back pain. We suspected that the external pressure of the hyperostotic spondylosis and massage might have caused the CIA compression and repeated crush of the stents.