Burke says while dancing the paso doble with partner Chris Jericho, "I felt something rip" in the upper inner thigh and groin region of her left leg.
Minutes after the broadcast, medics quickly treated Burke, who applied an icepack to the injury and grimaced in discomfort as she conducted post-show interviews.
The duo's routine, a crowd pleaser that was praised by the judges and received a solid 23 points, was full of quick movement and precise choreography.
"There was a move where I get down quickly," Burke, 26, told PEOPLE. "It bothered me [in rehearsals], but not like this. Now that the adrenaline of the live show is wearing off I'm feeling the pain a bit more."
Burke, a two-time Dancing champion, shrugged off what might have happened. "I'm getting old," she kidded.
Last week, fellow pro Maksim Chmerkovskiy was injured while performing the rumba with partner Kirstie Alley. (This week the pair suffered another mishap.)
One of the competition's nine remaining couples will be sent home on Tuesday's live results show, which airs Tuesday (9 p.m. ET) on ABC.