A teenager from Newport has permanent damage to her spinal cord after routine surgery to remove gallstones at a hospital in Birmingham.
Sophie Tyler, 17, now relies on a wheelchair.
Birmingham Children’s Hospital has apologised for the “unimaginable distress” it has caused.
They say they have implemented a series of changes to try to ensure it never happens again.
Sophie was 14 when she had an operation to remove gallstones on May 27 2008, the operation went well but a pain-killing epidural infusion was not removed for two days, permanently damaging her spinal cord.
A day after the operation she complained of numbness in her right leg.
After two days of receiving the epidural, the numbness had spread to both legs and Sophie was barely able to move her feet.
However, hospital staff did not stop the pain-killing anaesthetic until the night of 29 May.
An MRI scan revealed that the anaesthetic had entered the spinal cord and damaged the membranes, paralysing her from the waist down.
Dr Vin Diwakar, Chief Medical Officer at Birmingham Children’s Hospital said:
“We are deeply sorry for the unimaginable distress we have caused Sophie and her family as a result of the care she received at our hospital three years ago.
“The care we provided fell below our usual high standards and since then we have implemented a whole series of changes to try to ensure that this never happens again.”