 In these procedures, the thin protective layer around the nerve fiber, the basal lamina, is preserved so that, as a damaged fiber regrows, it travels within its basal lamina tube and connects with the correct loose end, and function may be restored.Surgically cutting a nerve severs these basal lamina tubes, and without them to channel the regrowing fibers to their lost connections, a painful neuroma or deafferentation pain may develop.This is why the neurolytic is preferred over the surgical block.