<P> A retractor is a surgical instrument used to separate the edges of a surgical incision or wound, or to hold back underlying organs and tissues so that body parts under the incision may be accessed . The general term retractor usually describes a simple handheld steel tool possessing a curved, hooked, or angled blade and 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 place, 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 other method . The term retractor is also used to describe 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 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 . </P> <P> Surgical retractors probably originate with very basic tools used 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). </P>

When would a retractor be used in surgery
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