Large amounts of polylactic acid in contact with divided nerve sheaths have no adverse effects on regeneration.

The stumps of divided rat sciatic nerves were coapted by suturing the epineurium to a small rectangular device made of a sheet of polylactic acid. One month later, significant degradation of the implanted material was observed. At that time, the local condition of the nerve was excellent, and the precise location of the initial injury could not be determined by examination under the operating microscope. Histology confirmed that there was no visible reaction to the biodegradable substance or its metabolites, and that neurotization of the distal stump was satisfactory. These findings were in agreement with those of other studies, and indicated that polylactic-acid devices affixed to divided nerves have no adverse effect on regeneration.