Retractor (medical)

A retractor is a surgical instrument with which a surgeon can either actively separate the edges of a surgical incision or wound, or can hold back underlying organs and tissues, so that body parts under the incision may be accessed. The two are each available in many shapes, sizes, and styles. The general term retractor usually describes a simple handheld steel tool possessing a curved, hooked, or angled blade fitted with a comfortable handle, that when in place maintains the desired position of a given region of tissue. These simple retractors may be handheld, clamped in situ, or suspended at the end of a robotic arm. Retractors can also be self retaining and not need to be held once inserted by having two or more opposing blades or hooks which are separated via spring, ratchet, worm gear or some other method and pull on opposite sides of a wound. The term retractor is also used to describe the distinct, hand-cranked devices such as rib spreaders (also known as thoracic retractors, or distractors) with which surgeons may forcefully drive tissues apart to obtain the exposure. For specialized situations such as spinal surgery retractors have been fitted both with suction and with fiberoptic lights to keep a surgical wound dry and illuminated.

Surgical retractors probably originate with very basic tool use in the Stone Age. Branches or antlers of various shapes were used to dig and extract food from the ground. As the use of tools evolved, a variety of instruments came about to substitute for the use of hooked or grasping fingers in the butchering of meat or dissection of bodies. The use of metals in tool making was of great importance. A variety of Roman metal instruments of the hook and retractor family have been found by archeologists. These instruments would generally be called hooks if the end was as narrow as the handle of the instrument. If the end was broad, it would be called a retractor. Also arising from this group of tools were other related tools for displacing (elevators and spatulas) and scooping (spoons and curettes).

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