In the last years the number of perioperative complications due to patiens ́ positions has increased. Surgical procedure are longer and de positions less physiological. Compartmental syndromes due to this reason are not common, and due to genupectoral position (knee-chest position) are unusual. However, this possibility must be considered in order to be able to do an early diagnosis and the treatment as soon as possible because of the seriousness of this syndrome and avoid irreversible tisular damage and the after-effects originated. A case of bilateral compartment syndrome of lower limbs in a female patient who was submitted to an artrodesis of lumbar spine by channel stenosis. The operation was performed in genupectoral position during seven hours with elastic bandaging in the legs. The patient developed secondary rabdomyolysis to the compartmental syndrome and a paralysis of external popliteo ciatic nerve as a sequel.