Nick Diaz got a fair bit of attention in 2008 when he went under plastic surgeon Frank Stile's knife for an innovative procedure to remove old scar tissue and grind down bones in the brow. Other fighters have since followed Diaz' example, including Marcus Davis who went to see Dr. Stile and Wanderlei Silva who, infamously, did not.
Former Sherdog/ESPN writer Jake Rossen has a feature on Stile for Wired, notable excerpt:
This is where Stile comes in. Bulky, broad-shouldered, with the features of a B-movie heavy, his Las Vegas practice is in the nucleus of the country's exploding MMA scene. Since his success with Diaz, he's performed the scar-tissue removal surgery on six other fighters. Some semi-pros have even come to him after a single cut in sparring, nervous they might be predisposed to career-altering lacerations.
"When these guys have their original injuries, whether it's in training or in an amateur fight or a pro fight, it all hinges on how well these wounds are addressed," Stile says. "Usually, they're closed by non-plastic surgeons, by emergency room physicians or some guy at the event."
Instead of being shut in layers, only the epidermis (the outermost surface) is stitched. The next time a set of knuckles strikes that area, it's like punching through tissue paper; the skin is closed again, poorly, and the cycle repeats. It's unstable material, and it has cost Diaz, as well as many others, not only fights but also the winner's share of the purse.
Rossen spends quite a bit of time mulling the question of whether or not this represents some sort of science fiction corruption of the purity of the sport. Personally, I don't see getting state-of-the-art plastic surgery as being any different than getting state-of-the-art arthroscopic surgery to repair a damaged knee.