A hairdresser's painful swollen left leg: artery compresses vein in May–Thurner syndrome

A 37-year-old hairdresser presented to our hospital with pain and swelling in her left leg and pain in her lower back. The pain in her back, which she thought was muscular, began as an ache, at the same time as the pain started in her leg, 5 days before. On the day of admission, over a period of 3 h, the back pain had become much worse and her leg had rapidly become swollen and more painful. As a hairdresser, she said she was on her feet for several hours every working day. She had no medical history of note: she did not smoke and was otherwise fit and well. The woman took no medication except for a combined oral contraceptive pill containing drospirenone and estradiol. On examination, the left leg—from the hip to the calf—was markedly swollen, painful, and cyanotic, consistent with a diagnosis of phlegmasia cerulea dolens. All pulses were palpable, and a sensory examination was normal; the lower part of her leg had a mottled, dusky appearance and a prolonged capillary refill time, and was cold to the touch.