Surgeons are preparing to insert stem cells into a dozen disabled New Zealanders in a bid to help them walk again.

Operations will start later this year on the first 12 New Zealanders with chest/stomach-level spinal injuries, as a clinical trial.

The Spinal Cord Society - a charity which has been funding research into stem cells - has won conditional approval to start the trials on paraplegic volunteers.

The trials will cost $2m, though the society has no government funding for them.

"I now believe it will be in my lifetime that people will go into hospital with a spinal injury and walk out a few months later just as though they'd experienced a broken leg,"' Spinal Cord Society chairwoman Noela Vallis said tonight.

Society spokesman Tony Edmonds said it was preparing additional information requested for a Multi-Region Ethics Committee meeting in Wellington next month at which he was confident of receiving full approval.

He said other programmes overseas had convinced a growing number of medical experts that an effective treatment for spinal cord injuries was getting much closer.

Mr Edmonds said at least a dozen New Zealand labs were researching non-embryonic adult stem cells for conditions such as brain injury and arthritis.

The procedure to be applied in New Zealand had been carried out overseas in countries such as Portugal, Italy, Japan and China on well over 100 people with few negative side-effects and varying degrees of improvement for each patient.

This had included recovering bowel and bladder-function, through to extra feeling and movement in limbs.

The procedure involves extracting nerve tissue from a volunteer's nose and inserting this into the injured area of the spinal cord.

Ms Vallis said the procedure offered no controversy over the source of cells because it involved a transfer of the patient's own cells.

"It's similar to a skin graft, so there is no need for complex anti-rejection drugs," she said.

"While doctors in other countries have actually made a start with these procedures, we have made use of the delays here, to continue studying the behaviour of human cells in our lab," she said.

"We are probably ahead of other countries in this knowledge."

Dr Jim Faed, the cell biologist and haematologist who manages the society's research programme and who will lead the clinical research team to undertake the trial operations, said there was still much to learn about the cell behaviour.

"The clinical trial we have planned, and the expected future trials, will help advance that understanding," he said.

Doctors were confident that the first trial was the right step to take in moving to human research, as it will go further than research overseas and collect important information about the mechanisms for improvement.

Dr Faed said if the operations confirm results found overseas while clarifying other key points identified by the research team, the society would be well placed to carry out trials of enhanced procedures.

Ms Vallis set up the society in 1991 to seek a cure for her husband's spinal injury, though he has since died.

"We are poised to bring possibly the greatest medical breakthrough in a century and we are doing it as a charitable organisation," she said. "We will need financial support".

On Tuesday, US President Barack Obama signed an order lifting eight years of restrictions on federal funding of human embryonic stem cell research.

His executive order reversed and repudiated restrictions placed on the research by his predecessor, George Bush, freeing labs across the country to start working with the valued cells, which give birth to all cells and tissues in the body.

New Zealand has not yet approved embryonic stem cell research, though a paper on the issue is reported to be before Health Minister Tony Ryall.