title: Letter: Nervous system involvement in ankylosing spondylitis.
mesh_terms: D006801:Humans; D009422:Nervous System Diseases / Q000150:complications*; D011832:Radiation Injuries; D011878:Radiotherapy / Q000009:adverse effects; D012509:Sarcoma / Q000209:etiology; D013167:Spondylitis, Ankylosing / Q000150:complications*