The human body is rarely able to repair nerve damage on its own, so often the best treatment for patients with nervous system injuries is to prescribe physical and occupational therapy to help the patient adapt to their permanent limitations. Several methods for nerve regeneration have been successful but only for limited applications. Some of the tried methods include relocating nerves from a healthy part of the body to create a graft at the site of nerve damage (a painful procedure with two surgical sites) and implanting a small, cylindrical channel made of synthetic, biocompatible materials to bridge the two free nerve ends (limited to regeneration in a straight line).
A collaborative project between scientists at University of Minnesota, Virginia Tech, University of Maryland, Princeton University, and Johns Hopkins University has led to a proof-of-concept for a 3D printed nerve guide that can regenerate nerves with more complex structures. This silicone guide is printed using a 3D scan of the nerve structure in a healthy individual and incorporates chemical cues that promote nerve growth. It is implanted at the site of damage and connected to the corresponding free nerve ends. A study was done using this method on the sciatic nerve in rat, which is responsible for controlling movement in the leg and foot muscles. A nerve guide was modeled after the sciatic nerve of a healthy rat. The nerve was then severed and the guide was implanted in its location. The rat regained much of its ability to walk in 10-12 weeks.
The next step would be to test this in humans. The researchers imagine that eventually a library of nerve structures could be created so that a 3D scan of a healthy nerve is not needed each time. This is an exciting development in nerve regeneration and for 3D printed devices.
Here’s video of a nerve guide being built using a 3D printer:
Source: University of Minnesota
Study in Advanced Functional Materials: 3D Printed Anatomical Nerve Regeneration Pathways