Intrinsic contracture in the hand is a crippling entity which is often unrecognized. The hand assumes a typical position with flexion of the metacarpophalangeal joints and extension of the interphalangeal joints. The thumb may be involved, and may exhibit marked flexion of the metacarpophalangeal joint and hyperextension of the interphalangeal joint. The loss of function is considerable,—the patient loses the essential functions of pinch and grasp. There are many possible causes,—ischaemia of the small hand muscles, spasm of the intrinsic muscles as found in rheumatoid arthritis and leprosy, and fibrosis resulting from direct trauma or thermal injuries. The treatment of choice is active splinting coupled with selective surgical excisions of the extensor aponeurosis, as suggested by Littler. The oblique fibers of the extensor hood are removed, thus releasing the extensor contracture; but the transverse fibers are preserved, thus retaining interphalangeal extension. This is best done through a single dorsal mid-line incision. Postoperatively, the patient's hand is splinted with the metacarpophalangeal joints at 180 degrees, but with the interphalangeal joints left free for the active motion that is to begin on the first postoperative day. By means of active splinting and this relatively simple surgical procedure, the vital functions of pinch and grasp are restored to the intrinsically contracted hand.
Since 1951 we have done this operation on twelve patients. Good results were obtained in all of these patients. One of the early patients in the series demonstrated slight clawing of one finger, due to excessive resection of the transverse fibers of the extensor aponeurosis. This difficulty was not encountered in the later cases in the series.