A traction splint most commonly refers to a splinting device that uses straps attaching over the pelvis or hip as an anchor, a metal rod(s) to mimic normal bone stability and limb length, and a mechanical device to apply traction (used in an attempt to reduce pain, realign the limb, and minimize vascular and neurological complication) to the limb. The use of traction splints to treat complete long bone fractures of the femur is common in prehospital care. Evidence to support their usage, however, is poor. A dynamic traction splint has also been developed for intra-articular fractures of the phalanges of the hand. Medical uses Traction splints are most commonly used for fractures of the femur (or upper leg bone). For these fractures they may reduce pain and decrease the amount of bleeding which occurs into the soft tissues of the leg. Some state that they are appropriate for middle tibia fractures which are displaced or bent. Others state they should not be used for lower leg fractures. Often a pillow splint or rigid splint is best in this situation. All agree that traction splints should only be applied when there are no fractures of the pelvis or knee and the fracture has not broken through the skin with bone visible. Use of a traction splint while other fractures in the leg exist will cause the weaker fracture site to pull apart and not the targeted femur fracture. Models There are two groups of traction splints: The Thomas half-ring group, which includes the Thomas splint, the modified Thomas splint, the QD-4 Hare traction splint and the Donway traction splint Non-half-ring group, which includes the Sager splint, and the most advanced; CT-EMS, Carbon Fiber traction system. The basic principle is that one end of the traction splint is positioned against the hip, and pushes upward against the pelvic bone. A strap around the foot and ankle is connected to the other end of the splint, and tightened to counteract the muscle tension and produce traction. Only then are additional straps added to aid immobilization of the limb. The Thomas half-ring splints consist of a padded half-circle of steel which is strapped to the hip, hinged to a U-shaped rod that extends along both sides of the leg. An ankle strap may be fashioned from cloth, and tied or twisted to apply traction force. It was devised by H.O. Thomas, initially for