In the operating room, the patient is placed on a four-poster table. The four posters support the iliac crests (pelvis) and the chest wall. Note that the abdomen is allowed to hang freely. When the belly is free, the great vessels (aorta and vena cava) are in a dependent position. The pooling of blood in the dependent position leads to significantly less blood loss.
Tables are radiolucent allowing for in surgery x-rays. The modern tables allow for heads-up or heads-down tilting, along with right and left side rotation. These motions allow the spine surgeon to protect his/her back and neck while looking down to operate. (Mizuho OSI® Union City, CA)