From the paper: 'Spared nerve injury (SNI) was performed in the left sciatic nerve (in mice)', ' Left hind paw inflammation was induced by intraplantar injection of etc.'.
Interesting question: if it's for the alleviation of pain in humans, how far should we go in inflicting pain on animals?
I don't know how you'd even begin to answer that question, unless the answer is either a complete dismissal of animal pain, or a total ban on animal testing.
Otherwise, I suppose you'd have to somehow quantify the total pain experienced and figure out how to minimize it. Which, frankly, seems impossible to do.
Interesting question: if it's for the alleviation of pain in humans, how far should we go in inflicting pain on animals?