Habilitation of Conjoined Twins (Ischiopagus Tripus) after Surgical Separation: A Case Report



This paper discusses the problems presented by, and the results of, a habilitation program for conjoined twins (ischiopagus tripus) who were the first of this type to be successfully separated by a team of physicians at Brookdale Hospital Center, Brooklyn, N.Y.

There are two prevalent theories regarding the etiology of the many varieties of conjoined twins: the fission theory and the collision theory.

The fission theory assumes that the embryonic cell mass divides in its main bulk but remains united at one of the poles or at a point between the two poles. As a result, the twins may be joined at any point (face, chest, shoulder, pelvis, etc.).

The collision theory presumes a secondary fusion of two separate embryonic axes developed on a single blastoderm.

There are two major types of conjoined twins:

  1. diprosopus, two faces with one head and one body;

  2. dicephalus, two distinct heads usually with separate necks and one body, categorized according to the areas of the body which are conjoined:

    Ischiopagus-joined at the inferior margins of the coccyx and sacrum with two completely separate spinal columns lying in the same axis.

    Pygopagus-joined at the lateral and posterior surfaces of the coccyx and sacrum which are single, the rest of the two bodies being normally duplicated (back to back).

    Dipygus-single head, thorax with abdomen, with two pelves or. two sets of reproductive organs or four legs.

    Syncephalus-joined at the face with the faces turned laterally, the right side of one and the left of the other. The rest of the twins may be separate or further joined at the thorax, but from the umbilicus down the bodies are separate.

    Craniopagus-joined at some homologous portion of their cranial vaults.

    Thoracopagus-part of the thoracic wall is common to both individuals.

    Omphalopagus-united from the umbilicus to the xiphoid cartilage.

    Rachipagus-united at the vertebrae column, at any point above the sacrum.

The conjoined twins described in the following case report were of the ischiopagus tripus type (Fig. 1 ).

Case Report

Sherrie and Sharisse (conjoined twins, ischiopagus tripus) were born June 15, 1967, at Brookdale Hospital Center in Brooklyn, N.Y., of normal Negro parents. Two previous pregnancies had been normal. Pregnancy and delivery were uneventful. Birth weight was 8 lb. 15 oz. The twins were fused at the pelvis with the trunks in the same axis (and the heads at opposite ends). Each twin was normal above the umbilicus. At right angles to the longitudinal axis, two normal lower extremities were present (one for each twin) and a single extremity projected from the opposite end (Fig. 1 ). Between the two normal limbs, a single set of normal external genitalia was present and a single stenotic anus opened posteriorly. Examination of X-rays revealed: the bones of the pelvis formed a ring with the pubic rami joined in the region of the normal lower extremities, and on the side of the fused extremity, the femur was single and articulated with a nonspecific portion of the pelvis to complete the circle. Two independent spines emerged with marked lumbar scoliosis (Fig. 2 and Fig. 3 ). Gastrointestinal series revealed: independent stomachs and small intestines and a single common large intestine. The two small intestines entered the common colon. Intravenous pyelograms revealed two kidneys, one bladder, and two ureters in each child, but only one ureter in each child contributed to the bladder. One of the twins had dextrocardia but without intracardiac pathology. An aortogram demonstrated that each had abnormal branching of the abdominal aorta. There were separate normal livers In November 1968, when the conjoined twins were 18 months old, separation was accomplished after a nine-hour surgical procedure. During the procedure, two uteri and two pairs of tubes and ovaries were found After separation, each twin was left with: an ileocolostomy; a bladder with two connected ureters (posteriorly located in one and anteriorly in the other); a uterus with its tubes and ovaries for each child A posterior anal fistula was provided to one twin and an apparently normal vagina to the other. Each child had her own urethra. Both twins tolerated the separation procedure very well. This surgery was accomplished by two teams, each one consisting of one surgeon, one assistant surgeon, one urologist, one anesthesiologist, one pediatrician, and one scrub nurse.

(We wish to acknowledge the achievement of the medical and paramedical staff of Brookdale Hospital Center, and express appreciation for their cooperation in providing photographs and medical data)

Problem of Wound Closure

It was anticipated that after the twins were separated a major problem would be that of abdominoperineal closure. Two measures were taken in preparation for this event:

  1. Since it was felt that the fused extremity would never be functional, the bones of this limb were removed on June 6, 1969. All other structures with their innervation were left intact. Essentially what was created was a large pedicle graft consisting of skin, fat, and innervated muscle attached to both children
  2. Despite the availability of this pedicle graft it was felt that approximation of the wound edges could be more easily obtained by stretching the parietes with pneumoperitoneum. Beginning on August 14, 1968, 500 to 1500 cc of air were injected at approximately three-day intervals. Sufficient air was injected to produce a tense abdomen without respiratory embarrassment. On two occasions, there was a rectal prolapse, but this was easily reduced. The abdominal diameter, measured at its greatest circumference, was increased by 12 cm.

During the operative procedure it was found that the anterior bony union was cartilaginous between the pubic symphysis of each twin. This was easily divided. The posterior union, in the region of the ischium, was bony and difficult to divide. Closure of the huge operative defect was easy and without tension. The previously developed pedicle flap was divided equally, and each half was swung into position in the appropriate twin. The peritoneum was approximated wherever it could be utilized, but the greater part of the closure was accomplished without peritoneal lining.

Referral for Habilitation

Sherrie and Sharisse were referred to the Institute of Rehabilitation Medicine Dysmelic Clinic in November 1969 at the age of 2 1/2 years. They were admitted to the Children's Division for a complete evaluation, prosthetic fitting, and training. Upon admission the clinical examination of Sharisse revealed an alert, cooperative, active and happy child, with the following characteristics: a right hemipelvectomy-type limb loss, dextrocardia, colostomy and genitourinary tract abnormalities The hip of the left lower extremity was flexed, abducted and externally rotated. The knee was flexed but a normal range of motion was present in the foot and ankle. She was able to bear weight on this limb No neurological abnormalities were noted. The skin around the scars and perineum was in good condition and the colostomy stoma clean and functioning well. X-rays and an intravenous pyelogram revealed marked lumbar scoliosis, subluxation of the left hip, and total absence of the right pelvis and the right lower extremity. The right kidney was very small, higher in the abdomen than the left, and close to the midline. Only the most rudimentary collecting system was present The left kidney was larger than the right but still quite small. The intrarenal collecting system showed dilatation of the pelvis but normal calyses

The clinical examination of Sherrie revealed that she was a well-nourished, well-developed, alert, and cooperative 2 1/2-year-old. Her vital signs were normal. A left hemipelvectomy and absence of the left lower extremity were evident. Other findings were: a colostomy with a well-healed stoma; the skin around the scars and perineum was in good condition; the neurological findings were negative; the upper extremities were good. The right lower extremity was rotated externally and flexed and abducted at the hip. The knee was in flexion and the foot in equinovarus. The Achilles tendon was contracted. X-rays of pelvis, hips, and spine revealed absence of the left hip, left pelvis and the entire left lower extremity. The right hip was subluxated. An intravenous pyelogram revealed that both upper collecting systems were well visualized. Both kidneys were higher and smaller than average The renal pelves were slightly dilated.

The patients were placed on an intensive program of physical training consisting of conditioning exercises for the trunk and upper extremities as a prerequisite for balance and ambulation Strengthening exercises for the sound limb were directed toward correction of the previously mentioned abnormalities, the achievement of balance and weight-bearing. Shortly after admission both girls were fitted with modified Canadian-type prostheses with rigid knees and shoulder-strap suspension. Although they accepted and tolerated the prostheses well, the deformity in the sound limb was severe enough to justify the addition of a brace. A long-leg brace with a waist belt connected to the prosthetic socket gave the needed support and corrected the rotation, abduction, and flexion disabilities. Prior to the prosthetic fitting Sherrie underwent correction of her equinovarus deformity by a lengthening of the Achilles tendon and a posterior capsulotomy.

Both children became ambulatory with the aid of a rollator During their six months of training they attended nursery school and both made impressive gains in all areas of development. No emotional conflicts were noted at any time.

Psychological testing revealed that both children had a mild delay in intellectual development probably as a result of their long hospitalization.

Since their discharge from the Institute of Rehabilitation Medicine, both children have been seen weekly by the Visiting Nurse Service for medical supervision and continuity of training. They also receive physical therapy at the Institute one hour a week. They were recently fitted with new Canadian-type hip-disarticulation prostheses with single-axis knee joints and SACH feet, which they handle very well. The long-leg brace is no longer needed and they now ambulate with complete independence and without crutches. Both children attend the Human Resources School for the Handicapped and have made an excellent adjustment (Fig. 4 ).

Role of the Parents

Both parents are playing a very important role in the progress of these children. Not only have they contributed to the therapeutic program but the home-nursing care has been excellent. The colostomies have been kept free from complications and in good condition. Both children wear disposable-type colostomy bags. They both have abnormal genitourinary systems and will probably need additional surgery to prevent deterioration of the kidneys. The lumbar scolioses present at birth as well as the hip subluxations will have to be followed very closely to prevent more severe spinal deformities (Fig. 5 ).

Without the comprehensive approach that was used and the cooperation of the parents and the involved agencies (school, visiting nurses, Bureau for Handicapped Children, etc.), the habilitation of these severely handicapped twins could not have been successful.

Institute of Rehabilitation Medicine, Children's Division, New York University Medical Center, New York, New York


    1. Guttmacher, A. F., and B. L. Nichols, Teratology of conjoined twins. The National Foundation - Birth Defects: Orig. Art. Series, 3:1:3-9, 1967.


  1. Mestel, A. L., R. J. Golinko, S. H Wax, B. Steiger, A. Kenin, R. Filler, and S. Landau, Ischiopagus tripus conjoined twins: Case report of a successful separation. Surg., 69:75-83, 1971.