Inequalities of bone length are an important cause of deformity of the human body. Shortness of an arm can be disguised satisfactorily by the clothing and is of little significance. A discrepancy in leg length produces a definite disability. Until the advent of anesthesia this deformity could be successfully treated only by the use of a high shoe or some prosthetic appliance. Although some of these gadgets were ingenious, they were always unsightly.
Rizzoli1 of Bologna was probably the first to equalize leg length deliberately. In 1845 he permitted the fragments of a fractured femur to override 3 in. so that the length was equal to that of the other femur, which had been short for 20 years because of a fracture. Impressed by the ease of this procedure, two years later he produced a fracture of the femur with an osteoclast which he devised. By permitting overriding of