Conjoined twins nicknamed the 'spider' have three legs, four arms and one penis in ultra rare phenomenon

Conjoined twins

Conjoined twins nicknamed the 'spider' have three legs, four arms and one penis in ultra rare phenomenon

American Journal of Case Reports
Holly Bishop

By Holly Bishop

Published: 15/05/2024

- 15:32

The twins underwent a recent operation to remove their third leg in order to allow them to sit upright

Conjoined twins have been the recipients of a study in Indonesia sharing three legs, four arms, and one penis, in a one-in-two-million phenomenon.

The twin boys, who also share a bladder, rectum, and intestine, were born in 2018. Their case was noted this week in a US medical journal.

The Indonesian boys, nicknamed the 'spider', are just a handful of Ischiopagus Tripus conjoined twins ever recorded.

Ischiopagus Tripus twins share three legs, where the third is often two fused together, as well as a shared set of genitalia, and the chance of surviving childbirth is extremely slim.

Conjoined twins

The twins share three legs, four arms, and one penis

American Journal of Case Reports

A study published in the American Journal of Case Reports by Indonesian researchers details a recent operation to remove the third limb and stabilise their hip and pelvic bone, which has allowed the twins to sit upright and potentially stand, allowing them more independence.

Three months after the surgery, the twins have suffered no major complications and there are currently no plans to separate them further.

Doctors also believe that one of the twins had an underdeveloped kidney, whilst the other only has one kidney.

Their parents had two older children, and there was no family history of medical issues. Their mother reported no complications during her pregnancy.


The boys’ condition mirrors the famous conjoined twins Ganga and Jamuna Mondal of India, who were labelled “The Spider Girls”.

Conjoined twins account for around 50,000 to 200,000 live births, and happen when a fertilised egg splits and develops into two individuals but remain physically connected.

The Indonesian researchers estimate that six to 11 per cent of all conjoined twins are Ischiopagus.

Last month, the world’s oldest conjoined twins died at 62 years old. Lori and George Schappell, whose skulls were partially fused together, passed away in hospital in Pennsylvania, USA, according to their obituaries.

\u200bLori and George Schappell Lori and George Schappell beat doctors' predictions that they would only live to 30Getty

Doctors told them that they would not live past 30, however, they defied expectations and went on to live separate lives, despite being attached.

Lori – who was able-bodied - pushed George around in a wheelchair, as he suffered from spina bifida.

The pair also became the first same-sex conjoined twins to identify as different genders, when George came out as transgender in 2007.

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