Researchers from University of Minnesota, Virginia Tech, University of Maryland, Princeton University, and Johns Hopkins University used a 3D scanner to analyze a rat's sciatic nerve. Using that data, they were able to 3D print a guide for nerve regeneration complete with chemical cues that guided both motor and sensory nerve regeneration. After implanting the guide surgically, the rat was able to walk in 10 to 12 weeks.
It's an important proof of concept that 3D printing nerve guides might be able to help regeneration of complex nerve injuries. Scientists have been able to regrow linear nerves, but this is the first time that a custom guide can grow complex Y-shaped nerves like the sciatic nerve. One research believes that someday there could be a database of scanned nerves from other people or cadavers that could be used to create new 3D-printed guides for humans.