title: Serum and knee synovial fluid matrixmetalloproteinase-13 and tumor necrosis factor-alpha levels in patients with late stage osteoarthritis.
abstract: OBJECTIVE
  To compare the levels of MMP-13 and TNF-α in late stage osteoarthritis, define their predominant pathways and investigate their correlation with McMaster Universities Arthritis Index scores.
  
  
  METHODS
  A total of 42 patients (mean age 64 ± 8.8) with grade 3 and grade 4 knee osteoarthritis according to Kellegren- Lawrence criteria and who were scheduled for total knee arthroplasty were enrolled in the study. TNF-alpha and MMP-13 levels were measured preoperatively from venous blood samples and intraoperatively from knee synovial fluid via ELISA. Preoperative and 1 month postoperative knee functions were assessed by McMaster Universities Arthritis Index.
  
  
  RESULTS
  Grade 4 synovial fluid MMP-13 (4.76 ± 5.82) was elevated compared to grade 3 (3.95 ± 4.45) (p = 0.438), whereas grade 3 serum MMP-13 (1.128 ± 0.308) was found elevated compared to grade 4 (1.038 ± 0.204) (p = 0.430). Grade 4 serum TNF-α (0.253 ± 0.277) was elevated compared to grade 3 (0.206 ± 0.219) whereas grade 3 synovial fluid TNF-α (0.129 ± 0.052) was elevated compared to grade 4 (0.118 ± 0.014). Positive correlation was observed between synovial fluid MMP-13 levels and postoperative WOMAC scores. Mean serum TNF-α level (0.226 ± 0.246 pg/ml) was found higher compared to synovial level (0.124 ± 1.59), synovial MMP-13 level (4.31 ± 1.24) was found higher compared to serum level (1.089 ± 1.519).
  
  
  CONCLUSIONS
  Despite the systemic increase in TNF-α levels concordant with osteoarthritis grade, MMP-13 levels are elevated via local manner with a significant correlation with WOMAC scores.
  
  
  METHODS
  Level IV, Diagnostic study.
authors.affiliation: Dr. Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Orthopedics, Ankara, Turkey.
authors.forename: Kenan
authors.initials: K
authors.lastname: Özler
authors.affiliation: Dr. Abdurrahman Yurtaslan Onkoloji Training and Research Hospital, Ankara, Turkey. Electronic address: drerdem2007@gmail.com.
authors.forename: Erdem
authors.initials: E
authors.lastname: Aktaş
authors.affiliation: Dr. Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Biochemistry, Ankara, Turkey.
authors.forename: Çiğdem
authors.initials: Ç
authors.lastname: Atay
authors.affiliation: Fatih Sultan Mehmet Training and Research Hospital, Department of Orthopedics, Istanbul, Turkey.
authors.forename: Barış
authors.initials: B
authors.lastname: Yılmaz
authors.affiliation: Dr. Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Orthopedics, Ankara, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Arıkan
authors.affiliation: Dr. Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Orthopedics, Ankara, Turkey.
authors.forename: Şafak
authors.initials: Ş
authors.lastname: Güngör
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D053509:Matrix Metalloproteinase 13 / Q000097:blood / Q000737:chemistry*; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D059035:Perioperative Period; D012698:Serologic Tests; D013582:Synovial Fluid / Q000737:chemistry*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000737:chemistry*
chemical_list: D014409:Tumor Necrosis Factor-alpha; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13
keywords: Knee osteoarthritis; Matrix metalloproteinase; TNF-alpha