Scientists in the US have successfully treated two puppies with a condition called spina bifida for the first time, promising effective treatment for both animals and humans.

Spina bifida is a rare condition that is caused when the spine or spinal cord doesn’t develop properly. As a result, it can hamper the movement of legs, and even cause paralysis.

In this first of its kind treatment, scientists at the University of California, Davis were able to restore leg movement in two bulldog puppies, named Darla and Spanky. Four months after they were born, they were able to walk and run.

“The initial results of the surgery are promising, as far as hind limb control,” said neurosurgeon Beverly Sturges, who led the research, in a statement. “Both dogs seemed to have improved range of motion and control of their limbs.”

Dogs born with the condition have little control over their hindquarters and so are often euthanized. These puppies are the first to have been successfully treated by a technique that was developed to help preserve limb function in children with spina bifida.

The treatment involved a combination of surgery and stem cell treatment. It had previously been shown that prenatal (before birth) surgery, combined with human placenta-derived mesenchymal stromal cells (PMSCs), helped lambs to walk after birth.

So Sturges applied the same approach to Darla and Spanky, when they were 10 weeks old. She used canine PMSCs this time, and the surgery had to be performed after birth, as prenatal diagnosis of spina bifida is not performed on dogs. The procedure was successful, and both dogs have now been adopted and live at a new home in New Mexico.

About 1,500 to 2,000 children are born with spina bifida in the US each year. It’s hoped that this latest breakthrough could help not only dogs, but humans too. The next step now is to get approval to begin human clinical trials.