Congenital Amelia: Prenatal Diagnosis and Postnatal Prosthetic Fitting

EUGENE BANZIGER, CO ANDRICHARD D. BEAUCHAMP, MD, FRCS


It has been said that a good prosthetic program is designed to begin helping congenital amputees and their families at birth and at the time of limb loss. We describe a child born with complete amelia; her deficiency was diagnosed in utero during a routine abdominal ultrasound for twin size assessment at approximately 7 months gestation (Fig. 1 ).

Brooks et al mentioned a crisis as occurring immediately following the birth of an incomplete child. The way the parents meet this crisis is a major determinant in the success of any future prosthetics program as well as being of great importance in the child's adjustment to society.1Hubbard stated that the majority of parents retained bitter memories of the early weeks following the birth of their defective child primarily because of the acute awareness of shock reactions on the part of hospital personnel, relatives, and friends. They have feelings of disgrace, being shunned and ignored.2 Thus, after weeks and months of excitement and anticipation prior to the delivery, the parents often feel they have let everyone down. A program of crisis intervention has been found to be very useful in assisting a family through this state.

Our situation in this case was somewhat different. The parents were referred to us by a geneticist after the prenatal diagnosis was established. I am sure the parents, however, had a glimmer of hope that the ultrasound was incorrect. We approached them directly and assumed their child would be born with a deficiency. Reading material was supplied regarding functioning with limb-deficient children, utilization of our social worker for counselling was undertaken and we put the family in touch with other families with limb-deficient children. At birth, after all the prenatal preparation was done, the family coped beautifully, as far as we can tell.

Prosthetic Fitting

Ashley presented a unilateral total amelia on the left (Figs. 2 -3 ). A happy and alert child, Ashley achieved sitting balance easily and the rehabilitation team decided fitting a shoulder disarticulation prosthesis would be appropriate. Her parents were very accepting of their daughter's disability and supportive of the program. In planning Ashley's first appliance, her parents requested that her prosthesis incorporate the attributes of her sound arm in size and appearance. Furthermore, they requested that the prosthesis allow all possible passive functions, including shoulder and elbow flexion and extension, humeral rotation, and supination and pronation of the hand. The prosthesis also should incorporate:

  1. comfort
  2. reliability
  3. excellent appearance
  4. durability
  5. light weight
  6. ease of adjustability for growth.

A plaster mold was taken of Ashley's shoulder and chest on the affected side. Length and circumferential measurements were taken of the sound arm. The plaster negative was filled and a positive mold produced which was modified in the conventional manner. A small sheet of Surlyn was heat molded to become the prosthetic interface. Surlyn was chosen for its overall wearing comfort and flexibility. The Surlyn was trimmed into a frame for coolness and access of air to the skin. The clear plastic allowed for a good visual check regarding fit.

The components for the structural parts of the prosthesis are readily available and are probably in the regular inventory of most prosthetic/orthotic facilities (Fig. 4 ).

Shoulder Joint: infant orthotic stirrup and infant aluminum orthotic ankle joint;

Elbow Joint: parapodium knee joint. The connecting pieces from hand to elbow to shoulder joint were modified from aluminum tubing available from parapodium systems;

Terminal Device: Centri passive hand with cosmetic glove. Assembly was accomplished in the following manner:

Shoulder Joint: The stirrup was cut in half and shaped so the shoulder joint was aligned parallel to the body's midline. The anterior part was sanded to allow free shoulder flexion and an extension stop of 0 degrees was retained. Friction within the joint was made adjustable by incorporating Teflon washers within the joint so that tightening a screw would increase the shoulder friction.

Elbow Joint: The aluminum ankle joint was cut to length and made to fit a piece of aluminum tubing of 1/8 inch (16 mm) in diameter, which in turn fitted the distal end of the parapodium joint (solid round part). TWO 6/32 inch (4 mm) rivets held the tubing to the orthotic ankle piece. A slot was made at the distal end of the tubing perpendicular to the length axis. The length of the slot was about a third of the circumference. A hole was drilled into the solid part of the parapodium joint and a 6/32 inch tap was used to thread it. A screw held the pieces together but allowed the components to slide in a circular fashion thereby providing for humeral rotation.

Terminal Device: Below the elbow, aluminum parapodium tubing was utilized 1/2 inch (12.5 mm) in diameter, to fit the open ended part of the joint. Cut to length the tubing could accommodate the threaded adapter of the cosmetic hand which is also 1/2 inch in diameter. The connection was made by a short sleeve of 5/8 inch (16 mm) tubing and fashioned together with two 6/32 inch machine screws. To allow for supination/pronation a perpendicular slot was cut into the open end of the parapodium and a 6/32 inch machine screw held it together allowing for rotation (Fig. 5 ).

Cosmetic finishing was accomplished by the conventional soft foam technique, with a 15K2 foam kit available from Otto Bock. The foam was shaped to copy the sound side and covered with flesh colored perlon stockinette for firmness and protection (Fig. 6 ).

The prosthesis was well received, with no fitting problems and the child wore the prosthesis full time during wakefulness from the start. This may be due to the semiflexible characteristics of Surlyn which allowed the socket to adjust to changes in the body shape that occurred during movement.

The three month check-up at the clinic was excellent. The prosthesis continued to fit well and all passive functions were intact and functional. The appearance was good and information regarding cleaning the cosmetic glove was related to the parents.

The passive prosthesis will be changed to a partially active one with an externally powered hand when Ashley is 17 months old.

Ford Laboratories, 106-11400 Bridgeport Road, Richmond, British Columbia V6X 1T2 Canada, (Mr. Banziger), and 210-650 West 41st Avenue, Oakridge Centre, South Tower, Vancouver, British Columbia V5Z 2M9, Canada (Dr. Beauchamp). Address correspondence to Dr. Beauchamp.

References:

  1. Brooks M, Beal L, Ogg L, Blackeslee B: The Child with Deformed or Missing Limbs: His Problems and Prosthesis. American Journal of Nursing 62:1962.
  2. Hubbard S: Social and Psychological Problems of the Child Amputee in Amputation Surgery and Rehabilitation, JP Kostuik, R. Gillespie, editors. New York: Churchill Livingston, 1981.
  3. Banziger E: Surlyn Socket Designs for the Young Child. Journal of the Association of Children's Prosthetic-Orthotic Clinics 24:12-13, 1989.
  4. Blakeslee B: The Limb Deficient Child. Berkeley: University of California Press, 1963.