Big Boi from Outkast -- Cleared for Doggy Style ... After Rehabbing Knee

Outkast rapper Big Boi tells TMZ ... he "lost his doggy style" abilities after blowing out his knee back in May ... but don't worry, the rapper tells us came up with a SOLID backup plan.

As you may recall -- Boi suffered a patellar tendon tear back in May while jumping around during a concert in Illinois ... and required knee surgery.

BB was at LAX yesterday rolling around in a wheelchair when he offered up the good news saying he can finally put pressure on his knee again ... which means, no more bangin' restrictions.

Big Boi wasn't completely deprived of his favorite position during his recovery though ... telling us he got crafty and figured out a way around the dilemma ... all thanks to a trusty piece of furniture.