A case report of an omphalopagus heteropagus (parasitic) twin.

Heteropagus twin refers to a type of conjoined twin in which an incomplete smaller (parasitic) twin is attached to and dependent upon an otherwise normal host twin. The majority of cases have complete or partial duplication of the pelvis and/or lower extremities. The case depicted herein is unusual in that only isolated case reports have described an attached amorphous mass without identifiable limbs.