Medicine: Arms, Made in Germany

During World War I an ingenious German surgeon, Ernst Ferdinand Sauerbruch, developed a plastic operation to link the muscles of an amputated stump to an artificial arm so efficiently that the live muscles could operate the fingers of an artificial hand. In a new book two German refugee surgeons describe the classic Sauerbruch technique (Cineplastic Operations on Stumps of the Upper Extremity; Grune & Stratton; $3.75).

The operation: two canals are fashioned In the muscles of the arm, one in the flexors, one in the extensors. The surgeon marks out a two-inch square of skin above the elbow or wrist (on a handless arm), cuts it at the top, bottom and one outer edge. Then he rolls the upper and lower sides of the skin into a little tube and stitches them together. This leaves the underlying muscle exposed.

Next the surgeon tunnels into the exposed muscle with a special steel dilator, twisting and turning until he has formed a canal in the muscle through which he draws the tube of skin. The bare muscle, which now encases the tube, is covered over with a patch of skin from some other part of the patient’s body.

The same operation is repeated on the other side of the arm. After the canals heal, an ivory peg is inserted in each one, and the patient practices moving these pegs with the stump muscles. Later on, a special artificial arm, made of many interacting levers and joints enclosed in leather, is fitted to the ivory pegs.

“The method of operation [of the arm],” wrote the doctors, “is somewhat similar to that of a two-horse carriage, where the pull is . . . apportioned and equalized between the two ends of a lever, the whiffletree.” Motor power is reduced to about 25% of normal, but this is still enough to enable patients to carry pails of water or pour water from one full pail into an empty one. The articulation is so perfect that the patient can hold and smoke a cigaret with ease.

Within a few months patients can do many of the things they could do with a real arm. They drive automobiles, write letters. “The sense of touch,” the doctors explained, “can be acquired to a remarkably subtle degree. The trained patient can be blindfolded and still recognize with his prosthesis (sawbone lingo for artificial arm) the slightest difference in the size of objects, as well as variation in consistency, and can also gauge the force with which he may wish to grasp an object.”