A famous example is Chang and Eng Bunker. Ischiopagus: Fused lower half of the two bodies, with spines conjoined end-to-end at a 180° angle. These twins have four arms; one, two, three or four legs; and typically one external set of genitalia and anus. Omphalo-Ischiopagus: Fused in a similar fashion to ischiopagus twins, but facing each other with a joined abdomen akin to omphalopagus. These twins have four arms, and two, three, or four legs. Parapagus: Fused side by side with a shared pelvis. Twins that are dithoracic parapagus are fused at the abdomen and pelvis, but not the thorax. Twins that are diprosopic parapagus have one trunk and two faces. Twins that are dicephalic parapagus have one trunk and two heads, and have two (dibrachius), three (tribrachius), or four (tetrabrachius) arms. Craniopagus parasiticus: Like craniopagus, but with a second bodiless head attached to the dominant head. Pygopagus or Iliopagus: Two bodies joined at the pelvis. Rachipagus: Twins joined along the back of their bodies, with fusion of the vertebral arches and the soft tissue from the head to the buttocks
Tricephalus (conjoined triplets): Extremely rare conjoining of 3 fetuses. Very few confirmed cases, both human and animal, are known. Management
Separation
Surgery to separate conjoined twins may range from very easy to very difficult depending on the point of attachment and the internal parts that are shared. Most cases of separation are extremely risky and life-threatening.
As of July 2019, both girls remain healthy and the family planned to return to their home in Pakistan in 2020. History
The Moche culture of ancient Peru depicted conjoined twins in their ceramics dating back to 300 CE. Writing around 415 CE, St. Augustine of Hippo, in his book, City of God, refers to a man "double in his upper, but single in his lower half—having two heads, two chests, four hands, but one body and two feet like an ordinary man. "According to Theophanes the Confessor, a Byzantine historian of the 9th century, around 385/386 CE, "in the village of Emmaus in Palestine, a child was born perfectly normal below the navel but divided above it, so that it had two chests and two heads, each possessing the senses. One would eat and drink but the other did not eat; one would sleep but the other stayed awake. There were times when they played with each other, when both cried and hit each other. They lived for a little over two years. One died while the other lived for another four days and it, too, died. "In Arabia, the twin brothers Hashim ibn Abd Manaf and Abd Shams were born with Hashims leg attached to his twin brothers head.