In an exceptionally rare event, conjoined twins born in Indonesia possess four arms, and three legs, and share genitalia.
Such twins are scientifically termed ischiopagus tripus and occur only once in every two million births.
Only a few cases of such conjoined twins, also known as ‘spider twins’, have been documented, with the case of the Indonesian boys recently published in the American Journal of Case Reports. Although the twins were born in 2018, their case was only recently published in the journal.
“The rarity of ischiopagus tripus conjoined twins complicates the surgical separation, due to the scarcity of cases and the high complexity,” the authors noted in the American Journal of Case Reports.
These twins are defined as being connected by the lower half of their bodies instead of the upper torso.
In over 60 percent of such cases, one of the twins either dies or is stillborn, yet these toddlers defied the odds and survived.
However, due to their unique body structure, the brothers had to lie flat for the first three years of their lives, as they were unable to sit up.
According to the case report, surgeons amputated their third leg, which typically consists of two fused legs, and stabilized their hips and legs so that the brothers could sit upright independently. A follow-up appointment three months after the surgery revealed that the twins did not experience any complications.
The twins have not undergone separation surgery, and it remains uncertain whether doctors will attempt such a complex procedure.
Nevertheless, doctors believe that this case underscores the possibility of surgical correction in cases where separation is not feasible.
Such births occur when the embryo only partially separates to form two individuals due to a congenital birth defect, as explained by the Mayo Clinic.
While the babies develop from this embryo, they remain physically joined, most commonly at the chest, abdomen, or pelvis.
