Biodegradable tube excels at treatment of nerve injuries

When someone has suffered a major nerve injury, there are two common treatments: performing a nerve graft, or utilizing a conduit to guide the regrowth of the injured nerve. While both approaches have their drawbacks, a new variation on the latter may succeed where they fail.

First of all, severed nerves are able to grow back together on their own. This is usually only the case if the gap between the two ends is no more than about a third of an inch, however. Any longer, and the regrowing nerve essentially misses its target, sometimes instead forming into a painful nerve-tissue ball known as a neuroma.

Therefore, for bridging larger gaps in places such as the arms, doctors usually perform a nerve graft.  Another option involves implanting a small conduit tube at the injury site. This guides the nerve as it regrows, ensuring that its two ends meet back up. According to scientists at the University of Pittsburgh, though, there are currently no commercially-available conduits that are FDA-approved for the bridging of gaps longer than one inch.

With that limitation in mind, those researchers have designed what they say is a better-performing tube. It's made from the same biodegradable polyester as dissolvable sutures, and is lined with microspheres of a growth-promoting protein called GDNF (glial-cell-derived neurotrophic factor). That protein is slowly released over the treatment period, continuously promoting nerve growth. No stem cells, which have been used in some other experimental conduits, are required.