title: Spinal pseudoarthrosis: a rare complication in psoriatic arthritis.
abstract: Discovertebral erosion with pseudoarthrosis is a well-known complication in ankylosing spondylitis but it is seldom mentioned in psoriatic arthritis. We report a 53-year-old woman with an 8-year history of psoriatic arthritis who developed severe low back pain followed by sudden onset of numbness in the lower limbs, weakness and dysesthesia. Abnormal contour of L1 and L2 vertebrae and intervertebral disc space was noted during radiologic examination. Pseudoarthrosis was suspected based on extensive osseous resorption and reactive sclerosis about the discovertebral junction on magnetic resonance imaging study. She underwent emergency operation due to spinal instability with neurologic deficit. Pseudoarthrosis was confirmed intraoperatively. No evidence of infection or neoplasms was found. This case shows that pseudoarthrosis can be complicated in patients with psoriatic arthritis, and this possibility should be considered in patients with previously quiescent disease.
authors.affiliation: Division of Immunology, Rheumatology and Allergy, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ko-Jen
authors.initials: KJ
authors.lastname: Li
authors.forename: Chia-Li
authors.initials: CL
authors.lastname: Yu
authors.forename: Chao-Yu
authors.initials: CY
authors.lastname: Hsu
authors.forename: Song-Chou
authors.initials: SC
authors.lastname: Hsieh
authors.forename: Ping-Ning
authors.initials: PN
authors.lastname: Hsu
mesh_terms: D015535:Arthritis, Psoriatic / Q000150:complications*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011542:Pseudarthrosis / Q000209:etiology*; D016103:Spinal Fractures / Q000209:etiology*; D013167:Spondylitis, Ankylosing / Q000150:complications