Baby With a Third Leg By K. Taniguchi, Y. Aoki, H. Kurimoto, and T. Okamura Izumiohtsu, Japan In Japan 0.66~ of newborn infants have congenital malformations; Muscloskeletal anomalies rank first and gastrointestinal defects are second. 1 An infant with a third leg is u n u s u a l and we have not found a similar reported case. A 2600-g full-term female was delivered by a Caesarean section. She had three legs and an ectopic anus. No other abnormalities were discovered on general examination, but an IVP and aortogram revealed aplasia o f the left kidney, hyperplasia of the right kidney, and vesicoureteral reflux. Nothing relevant was obtained from the family genetic history. However, her m o t h e r had received a plain abdominal X-ray examination and had been prescribed antibiotics for a period of 2 wk in the early gestation for pyelitis. The third leg was located in the center of her left buttock separate from the two normal legs and was about 10 cm in length with something like a knee joint (Fig. 1). There were five undifferentiated toes which were symmetrical from the middle toe. T h e leg responded to pain and touch, and the baby could move it freely. The Babinski sign was positive. A radiograph demonstrated bones corresponding to the femur, tarsals, and five metatarsals (Fig. 2). The third leg was a m p u t a t e d on the tenth day after birth. A cross section of the specimen was similar to a normal thigh. Her postoperative course was satisfactory and she has developed well. This third leg may be classified as a duplication or "dipodia. ''2 The teratoma and double-

Fig. 1. General view of the third leg at the left buttock and anal agenesis with rectovestibular fistula.

Fig. 2. Radiograph shows one (thigh) bone, tarsal bones, and five metatarsals. Journal of Pediatric Surgery, Vol. 10, No. 1 (February),1975

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monsters theories m a y also be considered. The former is the sacral teratoma and the latter is the pygomelus. Her atresia ani was an intermediate deformity with retrovestibular fistula according to the international classification of anorectal anomalies. 3 Because neither hereditary nor familial evidence was found, radiation and antibiotics administered during a few weeks of the embryonic period were identified as possible etiologic factors. REFERENCES 1. M o r i y a m a Y: Congenital anomalies in Japan. Sohgohrinsyoh (Jap.) (Clinic all-round) 12:2263, 1963 2. O'Rahilly R: Morphological patterns in

limb deficiencies and duplications. Am J A n a t 89:135, 1951 3. Smith ED: Proposed "international" classification of anorectai anomalies. A n n Chit Infant13:251,1972