title: TNF-α concentrations in pre-operative synovial fluid for predicting early post-operative function and pain after fast-track total knee arthroplasty.
abstract: BACKGROUND
  Tumor necrosis factor-alpha (TNF-α) helps regulate neuroinflammation and anxiety and could conceivable predict early post-operative pain and function after fast-track total knee arthroplasty (TKA).
  
  
  METHODS
  In patients with severe osteoarthritic knees undergoing TKA, we assessed: the correlations between pre-operative concentrations of TNF-α in synovial fluid; pre- and six-week post-operative knee function and pain; pre- and post-operative anxiety; pre- and post-operative synovial fluid concentrations of cartilage oligomeric matrix protein (COMP); age and body mass index (BMI).
  
  
  RESULTS
  Of 100 enrolled patients, 78 had evaluable TNF-α data, and 58 had evaluable COMP data. Pre-operative TNF-α concentrations were inversely correlated with post-operative pain scores during walking (rS=-0.26, P=0.03) and with change of pain at rest during six weeks after TKA (rs=-0.28, P=0.03) and were directly correlated with a higher post-operative Knee Society score (KSS) (rS=0.43, P<0.001) and with greater increases in this score during six weeks after TKA (rS=0.33, P=0.001). Mean TNF-α concentrations were higher in the 39 patients reporting any pre-operative pain at rest than in 36 patients reporting no pre-operative pain (P=0.015) and were the only independent predictor of pre-operative pain at rest (OR=13, P=0.02). Independent predictors of better post-operative knee function were higher log-transformed TNF-α concentrations (β=0.38, P=0.002) and male sex (β=0.28, P=0.02).
  
  
  CONCLUSIONS
  High levels of pre-operative TNF-α concentrations could be used as an independent predictor of better knee function at six weeks of follow-up. In patients with lower pre-operative TNF-α concentrations, post-operative pain management may improve the early outcome of the operated joint.
authors.affiliation: Department of Orthopaedics and Traumatology, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Pawel
authors.initials: P
authors.lastname: Zietek
authors.affiliation: Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Violetta
authors.initials: V
authors.lastname: Dziedziejko
authors.affiliation: Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Safranow
authors.affiliation: Zdroje Psychiatric Center, Szczecin, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Zietek
authors.affiliation: Department of Physical Culture and Health Promotion, University of Szczecin, Szczecin, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Stępień-Słodkowska
authors.affiliation: Department of Experimental and Clinical Pharmacology, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Bialecka
authors.affiliation: Department of Perinatology, Obstetrics and Gynecology, University of Szczecin, Szczecin, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Zietek
authors.affiliation: Department of Orthopaedics and Traumatology, Pomeranian Medical University, Szczecin, Poland. Electronic address: dkotrych@iwnirz.pl.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kotrych
authors.affiliation: Department of Orthopaedics and Traumatology, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Kamiński
authors.affiliation: Department of Stem Cells and Regenerative Medicine, Institute of Natural Fibres and Medicinal Plants, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Kowalska
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery*; D010149:Postoperative Pain / Q000209:etiology* / Q000378:metabolism; D011237:Predictive Value of Tests; D016059:Range of Motion, Articular; D020127:Recovery of Function; D013582:Synovial Fluid / Q000378:metabolism*; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: D014409:Tumor Necrosis Factor-alpha
keywords: Fast-track; Knee function; Rehabilitation; TKA; TNF-α