The "Jackass" star landed on his microphone pack as he did a front flip while rehearsing a salsa routine, aggravating a pre-existing back problem. He was taken to a hospital by ambulance and was unable to dance on Monday night's live show.
Usmagazine.com quoted host Tom Bergeron as saying Steve-O "hopes to be back next week."
The judges based their score of 14 out of 30 on Steve-O's dress rehearsal performance of the salsa with his professional dance partner Lacey Schwimmer.
TV personality Nancy O'Dell and singer Jewel were forced to drop out of the series before it began this season because they were injured during the show's rehearsal period.