Thoracolumbar rachipagus parasite.

A rare example of rachipagus conjoint parasitic twinning in a newborn girl is described. A lipomatous mass with an attached hind limb (with fused feet) and a rudimentary vertebral arch were found adherent to the dorsal vertebral arches of the autosite in the thoracolumbar region. There was a clear cleavage plane between the autosite and the parasite. Microscopic sections of the excised specimen showed gut only. The autosite had no other congenital anomalies except for spina bifida in the thoracolumbar region with unfolding of the underlying cord. In the absence of underlying life-threatening anomalies, surgical excision of the parasite and treatment of the associated anomalies of the autosite is known to offer gratifying results.