May-Thurner Syndrome and Surgery for Scoliosis

May-Thurner syndrome consists of the compression of the left iliac vein by the right iliac artery. We present the case of a 13-year-old girl with severe scoliosis and May-Thurner syndrome that became evident during surgery to correct the scoliosis. An initial attempt to treat the scoliosis employed a posterior approach using Isola instrumentation; however, the procedure was aborted due to the presence of enormous dilated perimedullary veins and hemorrhage. Angiography and venography confirmed the diagnosis of May-Thurner syndrome. Given the patient's age, the condition was not treated with an endovascular stent. She is currently awaiting definitive treatment. This is the first case in the literature in which varicose dilatation of the perimedullary veins in the spinal canal interfered with the surgical treatment of scoliosis. This case underlines the potential difficulties of surgery in the presence of myriad dilated perimedullary veins. May-Thurner syndrome should be suspected in scoliotic patients with dilated perimedullary veins.