title: [Significance of arthroscopy in the diagnosis of unilateral knee arthritis].
abstract: OBJECTIVE
  To investigate the role of arthroscopy in the diagnosis of unilateral knee arthritis of unknown causes.
  
  
  METHODS
  During December 2005 to February 2008,74 patients of unilateral knee arthritis of unknown origins were treated with arthroscopy. And magnetic resonance imaging (MRI) scans were performed for all of them before knee arthroscopy. The diagnosis was made by the synovial appearance in gross examination in arthroscopy combined with synovial pathology, synovial fluid analysis and clinical manifestations.
  
  
  RESULTS
  Among these patients, 71 cases were definitely diagnosed and 3 cases had unknown causes. Thirty-nine cases (52.9%) were of rheumatoid arthritis (RA), 7 (9.5%) of seronegative spondyloarthropathy (SPA), 7 patients (9.5%) of septic arthritis, 6 patients (8.1%) of RA coexisting gout arthritis, 5 patients (6.5%) of gout arthritis, 5 patients (6.5%) of tuberculosis of knee joint, 1 patient (1.3%) of pigmented villonodular synovitis and 1 patient (1.3%) of multicentric reticulohistiocytosis.
  
  
  CONCLUSIONS
  Arthroscopy provides valuable diagnostic information in unilateral knee arthritis of unknown causes. RA is the major cause of unilateral knee arthritis of unknown causes. Synovial appearance in gross examination in arthroscopy, synovial pathology and crystals are helpful to make a diagnosis.
authors.affiliation: Department of Rheumatology and Immunology, First People's Hospital of Foshan, Foshan 528000, China. cgqiang@fsyyy.com
authors.forename: Guo-Qiang
authors.initials: GQ
authors.lastname: Chen
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Zhang
authors.forename: Zhi-Feng
authors.initials: ZF
authors.lastname: Li
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Guo
authors.forename: Yang-Tao
authors.initials: YT
authors.lastname: Yu
mesh_terms: D000368:Aged; D001168:Arthritis / Q000175:diagnosis* / Q000209:etiology*; D001182:Arthroscopy; D005260:Female; D006801:Humans; D008297:Male