Joint manipulator (12)
I believe the answer is:
chiropractor
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">joint manipulator</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for chiropractor that I've seen before include "One who manipulates the spine" , "Joint manipulator" , "Spine manipulator" .)