Immobilization devices and stabilizers are pieces of medical equipment that keep a body part in a fixed position for an extended period of time and are often used during radiation therapy, medical imaging, and treatment of various injuries.Immobilization (medicine), the act of rendering immovable an injured or painful part of the body, usually an extremity or the spinal column. In bone fractures immobilization prevents injury to vessels, nerves, and other tissues by movable pieces of bone and creates the conditions for their knitting.