Evaluation of the CTX-II Biomarker in Patients with Anterior Cruciate Ligament Tear: Pilot Study.

Objective  The aim of the present study was to quantify the urinary concentration of the C-terminal cross-linked telopeptide of type-II collagen (CTX-II) biomarker in patients who suffered an isolated ACL injury, and to compare the concentrations found in this population with a control group of patients with no metabolic changes in the knee that could lead to cartilage degeneration. Methods  A cross-sectional pilot study was performed in two groups: patients with ACL tears and a control group (each group with 10 male subjects, with an age range between 18 and 35 years, and body mass index below 30 kg/m 2 ). In both groups, urine concentrations of a biomarker related to the degradation of type-II collagen (CTX-II) was measured. For the group with ACL tears, a temporal relationship between the time after the injury and the amount of the biomarker was also examined. Results  There were significant differences in the concentrations of urinary CTX-II between the ACL group and the control group ( p  = 0.009). No significant relationship was observed between the time after the injury and the quantity of the biomarker. Conclusions  Patients with ACL injury had higher concentrations of urinary CTX-II biomarker than those with no ACL injury ( p  = 0.009). However, there was no correlation between the concentration of this biomarker and the elapsed time after the injury ( p > 0.05).