Biochemical comparison of osteoarthritic knees with and without effusion
- Equal contributors
1 Department of Sports Medicine, West Chester University of Pennsylvania, 855 S. New Street, 313 Sturzebecker HSC, West Chester, PA 19383, USA
2 Division of Rheumatology, Tufts Medical Center, 800 Washington Street, Box 406, Boston, MA, 02111, USA
3 Department of Orthopaedic Surgery and Sports Medicine, Temple University, 3509 N. Broad Street, 5th Floor Boyer Pavilion, Philadelphia, PA 19140, USA
4 Department of Anatomy and Cell Biology, Temple University School of Medicine, 3500 N. Broad Street, Philadelphia, PA 19140, USA
5 College of Health Professions and Social Work, Temple University, 3307 N. Broad Street, Suite 300, Philadelphia, PA 19140, USA
BMC Musculoskeletal Disorders 2011, 12:273 doi:10.1186/1471-2474-12-273Published: 28 November 2011
Several symptom-relieving interventions have been shown to be efficacious among osteoarthritis (OA) patients with knee effusion; however, not every symptomatic knee OA patient has clinical effusion. Results may be over-generalized since it is unclear if effused knees represent a unique pathological condition or subset compared to knees without effusion. The primary purpose of this study was to determine if biochemical differences existed between OA knees with and without effusion.
The present cross-sectional study consisted of 22 volunteers (11 with knee effusion, 11 without knee effusion) with confirmed late-stage radiographic knee OA (Kellgren-Lawrence score ≥ 3). Synovial fluid samples were collected and analyzed using a custom multiplex enzyme-linked immunosorbent assay to determine eight specific biomarker concentrations (e.g., catabolic, anabolic).
Matrix metalloproteinase (MMP)-3, tissue inhibitor of MMPs (TIMP)-1, TIMP-2, and interleukin-10 were significantly higher in the knees with effusion than in the knees without effusion.
The biochemical differences that existed between knees with and without effusion provide support that OA subsets may exist, characterized by distinct biochemical characteristics and clinical findings (e.g., effusion).