Lmfao star Skyblu injured his back while performing the 'wiggle' dance move popularised by the duo's hit song Sexy And I Know It.
The rapper was forced to pull out of the group's live shows earlier this month (Dec11) after he was diagnosed with herniated discs and he is currently undergoing rehab treatment to strengthen his back.
Now his bandmate and uncle, RedFoo, has revealed the injury was caused by their crazy dancing.
During a TV appearance on breakfast show Good Morning America on Monday (19Dec11), RedFoo explained, "He (SkyBlu) hurt his back wiggling. We didn't know... Doctors said... it throws off his balance... When you wiggle, you have to balance it out and his muscles in his back, they just gave way."