An investigation into abnormally high cancer rates and heart problems among former Italian premiere league soccer players recently led to the discovery of an even deadlier killer that's taking out retired footballers.

Since 1973, 41 former Italian players have succumbed to motor neuron disease (MND), known in the U.S. as Lou Gehrig's disease. The mysterious ailment destroys the body's motor nerves, and eventually results in paralysis.

Stefano Borgonovo (pictured here), a former striker for AC Milan, is the latest victim of this incurable disease. The 44-year-old has been relegated to a wheelchair and now needs computer-generated voice software to communicate. While some speculate that it could be a result of physical injuries from tackles or repeatedly heading the ball, others think it could be the result of doping, or pesticides that are used on the stadium grass.

"The truth is, we just don't know," said neurologist Adriano Chio, who is the country's foremost expert on MND. Chio's research on the condition has found that soccer players have seven times the likelihood of contracting the disease. Midfielders -- who are frequently tackled -- seem to get it the most.

This baffling ailment is, of course, no laughing matter -- we hope the cause is discovered and the world's soccer players can return to doing what they do best: playing an intense game, entertaining millions of fans and (for 50 of them, anyway) sporting horrendous haircuts.

50 Greatest Football Haircuts

    Abel Xavier

    This isn't so much a haircut as an alien war helmet. Brilliant use of gel and dye by the LA Galaxy star.

    Getty Images

    Peter Beardsley

    Beardsley's commitment to the bowl cut was second only to his commitment to the England team.

    Michael Cooper, Getty Images

    Tony Daley

    Halfway through his haircut, Tony Daley was called to take his photo for that year's Panini football stickers.

    Dan Smith, Allsport / Getty Images

    Alexi Lalas

    Lalas had a truly amazing and intimidating haircut and beard combo during the 1994 World Cup. Now he manages LA Galaxy, which has more than its fair share of brilliant hair. Coincidence? We doubt it.

    Gary M. Prior, Getty Images

    Barry Venison

    This isn't a hair cut, he's just standing back-to-back with Chewbaca.

    John Gichigi, Getty Images

    David Beckham

    Beckham's long and distinguished daliance with strange hair started here, with the permanent mid-jump gravity hold.

    Getty Images

    Socrates

    Brazilian players with one-word names tend to have amazing hair. This wouldn't be an ego thing would it?

    Jorge Duran, Getty Images

    Billy Bonds

    One from the days before encroaching baldness meant a quick once-over with the clippers.

    Allsport UK / Getty Images

    Bobby Charlton

    Charlton's comb-over was truly a thing of beauty -- until he ran into the wind, that is, where it became a thing of nightmares.

    Bobby Charlton, Getty Images

    Carlos Valderama

    Hairdressers buy up tickets years in advance for when Valderama's Colorado Rapids and Abel Xavier's LA Galaxy meet in the MLS.

    Christopher Ruppel, Getty Images