Nerve Injury and Peripheral Nerve Functional Loss From Injection and Suture Needles: An Experimental Study on Rats

During invasive procedures involving needles, there is a chance of damage to peripheral nerves. Therefore, a method for experimentally simulating these situations is needed.

In this study we aimed to evaluate peripheral nerve lesions caused by the entry and exit of an injection needle, nerve transfixion through a suture stitch, and the injection of saline solution and lidocaine into the nerve.

After obtaining approval from the Animal Ethics Committee, we randomly divided 36 Wistar rats, weighing approximately 250 g each, into 6 groups (control, sham, suture, needle, saline, and lidocaine groups), with 6 animals in each group. All procedures were performed on the left paws of the rats. After the procedure, walking track analysis was performed to assess the walking function of rats for 8 weeks. Four months after the procedures, we performed bilateral electrophysiological studies (measuring the latency and amplitude of the electrical impulse in the peroneal nerve). Subsequently, the rats were euthanized, and bilateral tissue samples were collected from the peroneal nerve and tibialis cranialis muscle for morphometric histological analysis.

In the walking track analysis, all groups showed normalization of walking functionality after 13 days. There was little histological change between the groups, and no functional loss related to the procedures was observed.

Procedures involving the infusion of local anesthetic or saline solution, or suture needles, are safe with regard to peripheral nerve function loss. Accidents tend not to cause nerve impairment.