Traction splint

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.

A traction splint is commonly used to treat complete long bone fractures of the leg, femur and not for tibia and fibula area. Their use of 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.

Principles
Traction splints are most commonly used for shaft fractures of the femur (or upper leg bone) and not for fractures of the tibia and fibula. The femur is the longest bone in the body, the muscles surrounding the bone are also strong, when the bone is broken, the surrounding muscles often contract, pulling the bone ends past each other, causing additional injury and blood loss, pain, muscle, vascular and nerve damage.

Traction splints are applied only when the fracture is isolated to the femur and there are no other associated traumatic injuries to the leg or pelvis. 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.

History
The first widely used model of traction splint was introduced by Hugh Owen Thomas, a Welsh surgeon, considered by many to be the father of modern orthopaedic surgery. Prior to the introduction of the Thomas splint around 1916, mortality from femur fractures ran as high as 80%. Use of this splint reduced the death rate to less than 8%.

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 immobilization for tuberculosis of the knee. It is now commonly used for the immobilization of hip and thigh injuries.

The modified Thomas splint adapted the original Thomas splint to include a traction screw and foot plate and limb support built into the splint body.

The hare traction splint is a further adaptation of the Thomas splint. Its length is adjustable via telescoping rods, and it has built-in straps to support the hip and leg at several points along its length. It also provides a more comfortable ankle strap and a small winch that makes it much easier to apply and adjust traction force.

The Sager splint is an innovative splint that has introduced a new concept in the fixation of the consists of a metallic splint that is placed between the patient's legs. Some models may be placed on the side closest to the injury for bilateral femur fractures without pelvic trauma. Straps are then applied, first at the thigh and then at the ankle, to strap the injured leg to the pole and provide support. The pole is extended to supply the needed traction, and then both legs are wrapped with cravat-like straps.

The KTD (Kendrick Traction Device) eliminates the need for leg-raising and unnecessary rolling of the patient, and can be easily applied to both pediatric and adult applications. It consists of a round pole that can be located on the lateral aspect of the leg, with straps at the upper thigh and ankle for immediate placement, and three wider straps for immobilization. It is very light at 20 ounces. The KTD does not afford the rotational stability normally seen in long bone traction splints.

The CT-6 was introduced in the 21st century and utilizes a 4:1 pulley system to achieve precise and powerful, when necessary, traction. This splint is built with Carbon Fiber tubing and weighs in at just 500 grams. In 2003 the CT-6 was chosen as the splint of choice by the US military and currently has over 30,000 in the field. Its compact and light design, along with its greatly improved traction method, had greatly enhanced its popularity.

The Donway traction splint is a pneumatic splint that can be applied to a patient in situ. Acting on the ankle and groin pressure is then applied via an integrated pump. The devices itself consists of a metal frame that surrounds the leg that is then strapped into place.

Dynamic traction splint
In 1986, Robert R. Schenck used the same principals applied to treating femur fractures to develop a device for treating intra-articular fractures of the finger. The apparatus consists of a 6-inch-diameter circular splint that provides a rigid arc, with a 3-inch radius equidistant from the involved joint. A wire is placed horizontally through the distal head of the middle phalanx. The wire is attached by rubber band to a movable component attached to the hoop of the splint. The amount of traction can be controlled by using different types of rubber bands or tying knots in them. In 1993, a study conducted by Chinchalker and Patterson et al. involving 14 patients concluded "[I]mmediate mobilization of intra-articular fractures with dynamic traction predictably resulted in a functional joint".