Dancing with the Stars is often a battle of attrition.
It's one of the more physically and mentally demanding reality shows out there - and, as a result, the competition has taken its toll on a number of participants.
The following celebrities, for example, have been forced to leave Dancing with the Stars prior to actually being voted out:
Braxton is lucky to be alive. She formed blood clots on both of her lungs and was rushed to the hospital during Season 21, dropping out soon after. "With a Heavy heart I regret to inform you that my season of #dwts has to come to an end along with the rest of my tour dates with @musicbykem," she wrote on Instagram.
Also on Season 21, Kim Zolciak was unable to perform one week after suffering a stroke. She was therefore disqualified and went on to have heart surgery.
Billy Dee Williams
A chronic back issue cropped up and forced Billy Dee Williams out of Dancing with the Stars Season 18.
Jewel was supposed to compete on Season 8. However, she fractured her tibias just before the season began and Holly Madison took her spot.
Also took place prior to Season 8. This anchor withdrew after tearing her meniscus, which required surgery. Melissa Rycroft filled in and actually went on to win the All-Stars season.
After just two routine, the Olympic figure skater withdrew from the competition in season 16 due to a serious back injury.
This country artist exited the competition in Season 3 for personal reasons after filing for divorce from her then-husband, Craig Schelske. It was an ugly one.
The politican tried to compete, despite suffering a stress fracture prior to filming. Once that small stress fracture became a big one on Season 9, he had to withdraw.
OUCH! The Olympic volleyball star was forced to say goodbye after rupturing her Achilles tendon during a rehearsal, which required the her to undergo surgery soon afterward.
The young rapper (full name: Romeo Miller Jr.) was set to join Season 2 cast. However, suffered an injury before the competition officially kicked off and father Master P actually took his place. Romeo later competed on Season 12.
The professional dancer was unable to participate on Season 21 after tearing ligaments in her ankle during a rehearsal with Andy Grammer. The artist went on to partner with Allison Holker instead.
Season 14's Melissa Gilbert broke her back two years before going on DWTS and she and partner Maks had to work around that injury throughout her tenure on the show ... and then some. In her Week 4 Paso Doble, she hit her head and said she felt dizzy, so she was hospitalized. they took her to the hospital. She was diagnosed with a mild concussion and whiplash and had to bow out of the results show.
Bill Nye The Science Guy injured his quad during his second DWTS routine, and was diagnosed with a badly torn tendon. Using a brace to keep his leg immobilized, he attempted to dance anyway ... and did a decent job as a robot, actually. Alas, it was his final appearance in the competition.