A hospital in Memphis successfully separated 7-month old conjoined twins two weeks ago, and both are showing positive signs of surviving on their own, a Reuters report said.

Joshua and Jacob Spates, who were joined at the spine, are now recovering in the pediatric intensive care after a successful 13-hour surgery with a 34-member surgical team for their separation.

Dr. Max Langham, chief of pediatric surgery at Le Bonheur Children's Hospital, who led the operation, told Reuters that all involved are enjoying a "celebratory mood of how well Joshua and Jacob are doing."

The twins were delivered via Caesarean operation on Jan. 24, and separated on Aug. 29. Two weeks later, not only are the boys healthy, "both of them are using their legs and getting ready to try to crawl out of bed," Langham said.

Langham said members of the medical team "spent over a month" planning and rehearsing the operation, noting the trickiest part of the surgery involved dealing with the part of the spine shared by the boys.

"Most conjoined twins don't ever get a chance to get to separation because they die from complications at delivery," said Langham.

Conjoined twins occur in one out of 100,000 births. Joshua and Jacob were born pygopagus twins, joined back-to-back at the pelvis and lower spine, but with separate hearts, heads and limbs. This condition occurs in just 15 per cent of the cases of conjoined twins, according to Le Bonheur.