While Michael Jackson's moonwalk is perhaps the best known of all his groundbreaking dance moves, the late King of Pop also pioneered one that left many, including researchers, wondering how exactly he made the physically impossible play out on stage.

The move in question, the central focus of a new study published in the Journal of Neurosurgery, first debuted in Jackson's 1987 music video "Smooth Criminal." During a dance sequence, Jackson and an entourage of performers lock rigid and tilt their bodies at a straight 45 degree angle. The action appears impossible to pull off in real life, but there was Jackson and his crew, pulling it off again live on stage, as you can see in the video below.

While we know today that Jackson managed this extreme lean with the invention of a set of slotted shoes and a metallic peg protruding from the stage floor, neurosurgeons and study co-authors Dr. Nishant Yagnick, Dr. Manjul Tripath and Dr. Sandeep Mohindra discovered that was only half the answer.

In their paper, titled "How did Michael Jackson challenge our understanding of spine biomechanics?" the researchers explain how the spine reacts when we bend forward with a straight torso. The erector spinae muscles that run parallel to our vertebrae "act like cables" and keep us from tipping over. When bending at the ankles, however, as Jackson did in "Smooth Criminal, the strain is shifted to the Achilles tendon. This presents a very limited range of motion without a mechanical aide.

An illustration from the paper explaining how Michael Jackson pulled off his iconic lean move from 'Smooth Criminal.' An illustration from the paper explaining how Michael Jackson pulled off his iconic move from 'Smooth Criminal.' (Photo: Manjul Tripathi)

"Most trained dancers with strong core strength will reach a maximum of 25° to 30° of forward bending while performing this action," they write. "MJ pulled off a gravity-defying 45° move that seems unearthly to any witness. Several MJ fans, including the authors, have tried to copy this move and failed, often injuring themselves in their endeavors."

Even with the addition of the special shoes and floor pegs, the authors say Jackson and his dancers required core strength beyond what many of us could manage.

"Normal people, even with the shoe, probably can't do it," Yagnick told CNN. "It takes a lot of practice to develop the core muscles, abs and central trunk muscles to get the strength to do it."

So whether you're a child of the '80s or a new fan to the dance legacy left behind by Jackson, you may just want to leave this particular move on the dance floor to avoid falling on your face and incurring serious injury. For those looking for an alternative, we've included the below tutorial on the much safer and always impressive moonwalk.

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.