Osteoarthritis (OA) is a common age-related disabling locomotor disease characterized by degradation of articular cartilage (1).Clinical assessment of patients with OA is performed by assessing clinical features as: pain and mobility problems caused by joint destruction, and by radiographic method to assess cartilage damage (2).

The aim of this study is to investigate the patients with Knee Osteoarthritis by measuring the levels of C-terminal crosslinking telopeptide of collagen type II (CTX-II).

Urinary levels of C-terminal crosslinking telopeptide of collagen type II (CTX-II) as a marker of cartilage degradation was measured by ELISA using Nordic Bioscience Diagnostic Kit, and the concentration of CTX-II (in ng/liter) was standardized on the total urine creatinine (mmoles/liter), and the units for the corrected CTX-II concentration are ng/mmole, and the urinary levels of creatinine (jaffe) were measured by a Hitachi/Roche automated analyzer.

OA patients showed significant 1.39-fold elevation in U-CTX-II concentration as compared with healthy control group (P < 0.05). and was compared in the two groups in subjects aging above 50 years and was significantly increased in patients as compared with healthy control group (P < 0.05). U-CTX-II levels was elevated significantly with age in healthy control subjects (r = 0.76), and was higher in subjects with higher BMI (r = 0.34), and increased significantly in post-menopausal women as compared with pre-menopausal women (P = 0.0001) in health control subjects.

Our data suggests that the U-CTX-II assay is able to reflect the elevated cartilage destruction occurring in affected joints in patients with active Knee-OA. U-CTX-II levels increased with age suggesting that cartilage degradation is augmented with age, and in patients with higher BMI which is a risk factor affecting OA Patients. And U-CTX-II levels appear to elevate in post-menopausal women suggesting that the risk of knee-OA is elevated after menopause.

Key words: Osteoarthritis, collagen type II, CTX-II