"Doctor Doctor please," "They call me Dr. Love," "He’s the one you call Dr. Feelgood," "Gotta see my rock n roll doctor," "Somebody get me a doctor," "I’m your witch doctor," "Cause I’m the doctor," "Doctor me baby down to my soul." There’s a lot of metal songs about doctors.

But what we're here to talk about goes beyond the cheesy sexed-up role playing of heavy metal and beyond the hack and slash gore fiends of death metal. We're talking about the most brutal side of medicine... surgery.

After Twisted Sister set the surgery stage with "Under the Blade," Slayer took the subject much, much further with "Angel of Death." The surgical references Jeff Hanneman painted of Dr. Mengele and his cruel experiments on death camp prisoners is still horrifying. “Sadistic, surgeon of demise, Sadist of the noblest blood. Surgery, with no anesthesia, Fell the knife pierce you intensely.” It was so extreme that Def Jam records didn’t want to release it, but Slayer and producer Rick Rubin didn’t relent.

Of course, Carcass would become the most essential gore band in metal history, thanks in part to Jeff Walker's sister and a medical textbook she was using to become a nurse. The goregrind masterworks Reek of Putrefaction and Symphonies of Sickness birthed an entire subgenre of "Carcass clones" who used Pathology to create brutal metal. "They popped up everywhere, like a rash," Earache Records recalls. "Normally bands keep an eye on their progress via monitoring record sales, but Carcass had no sales numbers to speak of, so the band could only judge their success by number of their clones."

Watch our full video on why metal is so obsessed with surgery below.

Why Is Metal So Obsessed With Surgery?

50 Most Controversial Hard Rock + Metal Album Covers [NSFW]

More From KZCD-FM