Non-reducible rotational head tilt in ankylosing spondylitis.
D001270:Cervical Atlas; D006257:Head; D006801:Humans; D004204:Joint Dislocations / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012399:Rotation; D013167:Spondylitis, Ankylosing / Q000150:complications*