A new "train track" implant is being trialled by doctors with the aim of transforming treatment for patients with a severe spinal condition.

Evan Davies, a consultant spinal surgeon at University Hospital Southampton NHS Foundation Trust, has developed the device known as a Mesa Rail to treat scoliosis as part of a world-first research study.

The condition - which causes the spine to twist and curve - can affect people of any age, but most often develops between the ages of 10 and 15 and, in the worst cases, requires intervention to release pressure on the heart and lungs.

A Trust spokesman said: "The current standard surgical treatment to correct significant curves - 45° or more - involves placing two circular metal rods either side of the spine which are screwed in between the vertebrae, known as the Universal Spine System (USS).

"Using the Mesa Rail, surgeons slot the unique beam-shaped rail into smaller screws which enables it to be secured more rigidly to the spine, potentially helping to create better correction."

Mr Davies is trialling the device as part of a world-first study designed by his team over three years to compare the effectiveness of the new implant with the USS.

Mr Davies said: "This is a really exciting and much-needed study to provide some clarity on which device is most effective at treating severe cases of scoliosis.

"The Mesa Rail has an innovative beam shape - similar to the way a train slots into railway tracks - which fits neatly into smaller screws.

"This enables us to get closer to the spine, push and apply more force to correct it, with leaving less room for movement - whereas the USS rods are round so not as stable in shape.

"There is some evidence that the Mesa Rail can provide better realignment of the curve and, if this can be proven to be maintained long-term, it will reduce the need for further surgery."

The study will recruit 60 patients over the next two years at Southampton General Hospital and Southampton Children's Hospital, where surgeons currently operate on around 250 scoliosis patients a year.