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 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.
History
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 and scooping. In 4th century CE, Indian physician Susruta used surgical tools such as retractors. In a description of the procedure of tonsillectomy from the 7th century CE, Paul of Aegina documents the use of a tongue spatula to keep the tongue out of the way while a form of tonsil hook is used to bring the tonsil forward for excision. In 1000 CEAbu al-Qasim al-Zahrawi, also known as Albucasis or Abulcasis, described a variety of surgical instruments including retractors in his famous text Al-Tasrif. Vesalius described a variety of hooks and retractors in the 16th century. Jan Mikulicz-Radecki's invention of a hinged rib spreading retractor in 1904 prompted a flurry of development of retractors in the early 20th century, culminating in 1936 in our modern device based on the design of Enrique Finochietto.
Current
The following is an incomplete list of surgical retractors in use:
