Conjoined twins separated by incredible surgery even though they shared one liver, one bladder and three legs

Doctors successfully separated two-year-old conjoined twins in one of the most difficult operations in medicine.

Erika and Eva Sandoval were said to be in a stable condition after a mammoth 17 hours of surgery at Lucile Packard Children's Hospital in Palo Alto, California, last night.

Separation surgery is performed about five times a year in the United States, with doctors successfully handling one last month in Memphis, Tennessee, on twin sisters born in Nigeria.

But on this occasion it was much more challenging because the twins shared most of their lower body.

Between them Erika and Eva had just one liver, one bladder and three legs.

The surgical team divided the bladder into two separate organs.

It also split the liver to give half to each child.

The girls each have one leg, with doctors using the third leg for reconstruction, taking its skin and muscle to close one child's abdominal wall.

The girls are expected to remain in the intensive care unit at the hospital for two weeks.

They are sharing a hospital room in separate beds.

Most conjoined twins die in the womb, and about half who are born alive do not make it past a day.

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