Doctors from China and Hong Kong have transplanted human spinal discs into five patients, offering what could be a viable alternative to treat degenerative disc disease (DDD) in the future.
The soft, compressible discs that separate the interlocking bones that make up the spine can break down with age, becoming drier, less flexible and more easily damaged.
They act as shock absorbers for the spine, allowing it to flex, bend and twist, but slipped discs can affect nerve function, leading to numbness and pain in a leg or arm.
Writing in the latest issue of the Lancet, researchers said they transplanted spinal discs from three young female donors who had died from trauma into five patients suffering from DDD from March 2000 to January 2001.
The article did not say whether the operation took place in Hong Kong or on the mainland, but said the patients were closely monitored for five years.
"The neurological signs and symptoms of all the patients improved after the operation... none of the patients had any persistent or clinically significant neck pain at rest or during neck movement," they wrote.
They said human spinal disc transplants could become a viable future treatment for DDD with further improvements.
In an accompanying comment published in the journal, experts not involved in the study said human disc transplantation may provide an attractive alternative to current treatments, such as spinal fusion and artificial disc transplants.
Spinal fusion permanently connects two or more bones in the spine to improve stability, correct a deformity or treat pain. In some cases, bones, rods and screws are used to fuse vertebrae.
But areas of the spine adjacent to the fusion will bear more stress, making them more vulnerable to future wear and tear.
"The feasibility of the technique has now been shown and disc transplantation could be an attractive alternative both for fusion and artificial disc replacement, providing an appropriate donor is found with adequate geometry," wrote Wafa Skalli and Jean Dubousset at Biomechanics Laboratory in France.
"This approach could be of particular interest for younger patients for whom prevention of adjacent-level degeneration is important."
