Decreased L5 spinal nerve ligation nociceptive behavior following L4 spinal nerve transection

This study used the escape/avoidance paradigm to explore the role of the L4 spinal nerve in L5 ligation nociception. Unlike L5-ligated controls, L5-ligated/L4-transected animals had normal mechanical withdrawal threshold and did not escape/avoid mechanical stimulation of the afflicted paw. The result from the escape/avoidance paradigm, which does not rely on a reflexive withdrawal response, directly supports the hypothesis that the L4 spinal nerve contributes to L5 ligation neuropathic pain.