Identification of spread after deliberated intraneural injection in five mammalian species: not all animal models and needle types are valid for studying the effect of intraneural injections in humans.

Despite the formidable challenges associated with the practical realization of intrafascicular injection, the utilization of animal models possessing monofascicular or oligofascicular nerves, such as rats, rabbits, and dogs, in conjunction with needles featuring aperture dimensions surpassing those of the fascicles, likely contributes to the compromised reliability of investigations into intraneural injection outcomes.