Fractures, or broken bones, are one of the most common medical problems. It is estimated that 6.8 million fractures occur in the United States each year alone, with approximately 900,000 of them requiring hospitalization. To treata fracture so that the patient regains full use of an injured arm or leg thebone ends must first be brought back into alignment; then, the fracture mustbe held together until the bone ends grow back together. Closed or simple fractures, in which the bone ends do not penetrate the skin, have always been relatively easy to treat. Open or compound fractures were usually fatal prior to the advent of antiseptics in the 1860s because infection would set in. The earliest method of holding a reduced fracture in place was to use splints--rigid strips laid parallel to each other alongside the bone. Ancient Egyptians used wood splints made of bark wrapped in linen to hold broken bones in place. Ancient Hindus treated fractures with bamboo splints. The writings of Hippocrates discuss management of fractures in some detail, recommending wooden splints plus exercise to prevent muscle atrophy during the immobilization. Next, medical practitioners thought of stiffening the bandages that held the splints in place. The ancient Greeks used waxes and resins for this purpose. The Roman Celsus, writing in a.d. 30,describes how to use splints and bandages stiffened with starch. Arabian doctors used lime derived from sea shells. The Italian School of Salerno in thetwelfth century recommended bandages hardened with a flour and egg mixture. Medieval European bonesetters used casts made of egg white, flour, and animalfat. In the sixteenth century the famous French surgeon Ambroise Paré; (1517-1590) made casts of wax, cardboard, cloth, and parchment that hardened as they dried. Splints remained the basic method of immobilization until 1852, when a Dutch army surgeon, Antonius Mathijsen, introduced rollerbandages impregnated with quick-drying plaster of paris (gypsum). Brokenbones could be held in place while the wet bandages were applied; when dry,the bandages became a rigid cast that held the bones perfectly in place during healing. As Mathijsen himself pointed out, Arab physicians had used plastercasts for centuries, but knowledge of the technique hadn't reached the Westuntil the end of the eighteenth century. Plaster of paris casts have remainedstandard treatment for fractures. Beginning in the early 1980s, casts made of fiberglass plaster have also come into use and are favored for their lightweight and water resistance. In addition to splints and casts, fractures havebeen treated with extension and traction. The ancient Greeks used traction--pulling on a broken limb with weights and pulleys--but that practice died out until after the Middle Ages. Traction was revived by the eminent French surgeon Guy de Chauliac (1300-1368) during the fourteenth century. The gifted orthopedist Hugh Owen Thomas (1833-1891) of England devisedimproved methods of traction as well as the Thomas splint, still used today,which allowed for extension of the limb. Hugh Arbuthnot Lane (1856-1943) ofGreat Britain devised a way to hold broken bone ends together mechanically when they would not heal together naturally. In 1893 he introduced the use of steel screws to rejoin bones and then improved the technique around 19O5 by using steel plates screwed into the bone ends. Lane's method, of course,could only succeed after Joseph Lister (1827-1912) had introduced antisepsics to surgery, and successful treatment of compound fractures also depended on Lister's innovation. Compound fractures meant heavy contamination ofthe wound, which almost always led to severe infection and usually resulted in death. Since infection could not be avoided in pre-antiseptic days, the usual method of treating compound fractures until the late nineteenth century was amputation--which, in the case of removal of the thigh, also often resultedin fatal infection. Once Lister began the era of antiseptic surgery in 1865,infection in compound fractures could be controlled and these injuries couldat last be treated successfully with surgery, casts, and plates.