A Recent Articie Of Interest

The following is an abstract of an article, "The Krukenberg Procedure in the Juvenile Amputee," by Alfred B. Swanson, M.D., of the Area Child Amputee Center, Michigan Crippled Children Commission, Mary Free Bed Guild Children's Hospital and Orthopaedic Center, Grand Rapids, Michigan. The article appeared in The Journal of Bone and Joint Surgery, Volume 46-A, Number 7, October 1964. All the accompanying illustrations are reproduced with the permission of The Journal of Bone and Joint Surgery.)

Prehension can be satisfactorily restored to the bilateral upper extremity amputee by means of ordinary prosthetic fitting, but the absence of a sense of touch makes this method of rehabilitation less than ideal. Therefore it should not be overlooked that tactile gnosis with prehension can be provided in these cases by the Krukenberg procedure. This surgical procedure divides the forearm stump between radius and ulna, converting it into two large "fingers" or rays, which function on the simple mechanical principle of chopsticks (Fig. 1A and Fig. 1B ).

The Krukenberg procedure has generally been considered suitable for blind patients with bilateral hand loss, and for bilateral upper extremity amputees living in regions where prosthetic service is unavailable. This article recommends that the Krukenberg procedure should be considered for every patient with bilateral hand loss who has a forearm stump of adequate length.

The advantages to the patient are multiple and constant -- an increase in dexterity and ease in such daily activities as dressing, bathing, eating and toileting.

The disadvantage is thought to be appearance, but a conventional prosthesis can be fitted over the Krukenberg stump for wear outside the home, should the patient desire it. None of the patients described in this article has done so. All use the Krukenberg stump as a dominant hand, never covered by an artificial limb. The general feeling is that it is no more uncosmetic than a useless stump, or a hook.

Recommended for Juvenile Cases

The Krukenberg procedure should be performed in children as soon as feasible; it can safely be performed in the child's second year. The very rapid, useful, functional pattern of prehension developed by the children described in the article demonstrates the value of early reconstructive surgery. The epiphyses are not disturbed if the procedure is done carefully so that growth considerations should not be a limiting factor.

Objective of Operation

The objective of the operation is to convert the forearm into a strong active forceps with radial ray opposed to ulnar ray. The forceps should spread wide enough to accommodate objects such as a drinking glass and be strong enough to provide a firm grip. Therefore, appropriate length and spread, and proper muscle placement must be achieved. Tactile sensation should be present between the tips, and therefore the skin must be of full thickness with good nerve and blood supply.

Procedure

The operation is performed with a tourniquet in place to provide a bloodless field. The length of the incision proximally is determined by the pronator radii teres, which should not be disturbed as this muscle will become the strongest adductor of the radial ray.

Any digits present should be retained (Fig. 2A and Fig. 2B ). In some cases, these digits can be rotated to a more useful position opposing the other ray.

The muscles, tendons and nerves are divided between the radial and ulnar rays, according to function (Fig. 3A/3B ). Certain of the muscles may be resected if they make the stump too bulky. The distal ends of the tendons of the retained muscles are securely sutured to the periosteum and capsular tissues at the distal end of the radius or ulna.

The interosseous membrane should be divided throughout the length of its ulnar periosteal attachment. In juvenile cases, the distal ulnar and radial epiphyses should be carefully preserved. The epiphyseal plate should not be crossed in the dissection, and care should be taken not to damage this structure in the preparation of the tips of the forceps.

The ulnar and radial rays are then spread six to twelve centimeters at their tips, depending on the size of the forearm.

The separation of the rays and their covering with skin follows the syndactylism procedure designed by Bunnell to separate web fingers. Following the Bunnell technique, one or two V-shaped flaps of skin are used at the proximal end of the wound to provide full-thickness coverage in the axilla (Fig. 4A and Fig. 4B ).

The distal portion of the rays are covered by skin flaps rolled onto the opposing surface in such a way that the distal tips will be free of scar tissue. Skin for these flaps is readily available, because there is usually an abundance of skin in limbs with congenital malformations. The skin is rotated around the rays and positioned away from the contact surfaces. Excess muscle substance, fat and fibrous tissue are resected to allow wound closure without tension on the skin flaps. A small split-thickness skin graft, taken from the abdomen or thigh, is used to cover a portion of the wound on the proximal volar aspect of the radial ray.

Closure and fashioning of the secondary flaps, at tips and axilla, are done with the tourniquet deflated to allow for observation of the blood supply to the skin.

Small rubber drains are left in the wound, and a voluminous compression dressing is applied, separating the rays. The limb is usually elevated for three days to improve venous return.

Rehabilitation

A training program is started within two to three weeks. The patients seem to acquire the ability to grasp and release naturally. Pronation and supination are strong normal movements. Abduction and adduction of the rays, however, are the important motions to be learned if the patient is to obtain the most benefit from his Krukenberg stump. The occupational therapist is invaluable in training these patients and in stimulating them to early and proper use of the forceps. The patients very rapidly learn their own combinations of adduction-abduction, pronation-supination, to accomplish their daily activities.

The patient is encouraged to use standard implements to learn to adapt to a normal environment. Two-handed activity is encouraged, using the hook on the opposite side. This new functioning and grasping mechanism with skin sensibility stimulates cooperation by the patient so that rehabilitation is relatively easy and rapid.

Four Subjects Described

The Krukenberg procedure was performed unilaterally on four juvenile amputee patients with congenital bilateral absence of the hands, at ages 2, 3, 7 and 14. The opposite extremity was fitted with a standard prosthetic prescription as an assistive hand. The oldest patient in this group, now aged 28, developed a pinch force equal to ten pounds, with a 2 1/2" opening at the tips of the rays. The youngest, now six years old, has a pinch force of two pounds, with an opening of 1 1/2". These children learned to feed and dress themselves, to pick up objects as small as needles, and to distinguish various objects blindfolded. One of the boys learned to throw a baseball with the Krukenberg stump, and at recess plays outfield on his school team.

Conclusion

The experience with these patients would indicate that the Krukenberg procedure should be extended to more individuals who have the severe handicap of bilateral hand loss.