Association between the Severity of Knee Osteoarthritis and Serum Cartilage Biomarker Levels
Apiruk Sangsin MD*, Dumnoensun Pruksakorn MD, PhD*, Sirichai Luevitoonvechkij MD*, Peraphan Pothacharoen PhD**, Prachya Kongthaweelert PhD**
Affiliation : * Department of Orthopaedics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand ** Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
Background : Osteoarthritis (OA) is the most common form of arthritis. However, there has been no cost-effective tool for
the investigation of the severity and progression of the disease because using OA standard diagnostic methods causes
cartilage damage.
Objective : To evaluate the relationship between serum chondroitinsulphate WF6 (CS- WF6) and hyaluronate (HA) and the
severity of knee OA according to Kellgren-Lawrence (K/L) grades of radiographic severity and minimal joint space width
(JSW).
Material and Method: One-hundred and twenty-six patients with OA (knee) according to K/L grades were classified into
four groups. The JSW of the tibiofemoral joint were measured from standing PA radiographs. Serum CS-WF6 and HA were
analyzed by the ELISA based technique. One-way analysis of variance, Bonferroni’s method and Kendall’s tau coefficient
relation test were performed to evaluate the association of K/L grades and JSW with levels of CS-WF6 and HA, respectively.
Results : Serum CS-WF6 levels in grade 4 were significantly increased when compared with the other grades (p<0.05). The
serum HA level did not show any significant difference among the grades of severity. The serum CS-WF6 level showed a
significant negative correlation with the JSW and its levels rose rapidly to the level beyond 300 ng/ml. There was no
correlation found between the levels of serum HA and JSW.
Conclusion : WF6 levels may be useful in identifying patients at risk of rapid progression reflected by a point of an abruptly
high WF6 level. The determination of WF6 in the serum showed increasing levels in more severe grades, so it could be
useful in monitoring the effectiveness of treatment. There were some limitations because of broad distribution and overlap
with the normal range. Thus, it may not be suitable as a diagnostic tool.
Keywords : Biomarkers, Cartilage, Osteoarthritis, Chondroitin sulphate WF6
