Ішек қосқан егіздер: Медициналық аспектілер мен хирургиялық араласулар

Conjoined twins fused at the pelvis

Ischiopagi comes from the Greek word ischio meaning hip (ilium) and pagus meaning fixed or united. It is the medical term used for conjoined twins (Class V) who are united at the pelvis. The twins are classically joined with the vertebral axis at 180°. The conjoined twins usually have four arms; two, three or four legs; and typically one external genitalia and anus. It is mostly confused with pygopagus where the twins are joined dorsally at the buttocks facing away from each other, whereas ischiopagus twins are joined ventrally and caudally at the sacrum and coccyx. Parapagus is also similar to ischiopagus; however, parapagus twins are joined side by side whereas ischiopagus twins typically have spines connected at a 180° angle, facing away from one another.

Ischiopagus Dipus: This is the rarest variety with the twins sharing two legs with no lower extremities on one side. Ischiopagus Tripus: These twins share three legs, the third leg is often two fused legs, or is non functioning. The twins also usually share only one set of external genitalia. Ischiopagus Tetrapus/Quadripus: This variety has the twins at a symmetrical continuous longitudinal axis with their area of union not broken anteriorly. The axes extends in a straight line but in opposite directions. The lower extremities are oriented at right angles to the axes of the thorax and the adjacent limbs near the union of the ischium belong to the opposite twin.

Conjoined twins are at high risk to being stillborn or dying shortly after birth. In some cases, a healthy twin and a parasitic twin are born. The parasitic twin has no hope for survival and dies and is then surgically separated from its twin. Depending upon how the twins are attached and what is shared among them, complications can arise from surgically separating the live twin from the dead twin. In Ischiopagus cases, the children share a pelvic region along with the gastrointestinal tract and genital region. Ischiopagus twins need reconstructive surgery for the genitals and gastrointestinal tract in order for normal bowel movements and reproductive possibilities in adulthood. For the Ischiopagus twins that both survive from birth, complications and risks also arise. Usually if both twins survive labor, one twin will be healthy and strong, while the other is malnourished and weak. Thus, surgery would have to be planned in advance to understand the best option and how to keep both children alive during surgery as well as afterwards.