CXM Biomarker has a Strong Association with Canonical Bone Turnover Markers During Fracture Repair.

(A) VitaShock (NCT02786498) participant flow diagram. IU, International Units (B) Collagen X biomarker (CXM) concentration plotted at 0, 6, and 12 weeks for the four different Vitamin D3 (VD3) treatment groups showed no significant difference in CXM between any treatment groups. (C) N-terminal propeptide of type I procollagen (P1NP) concentration plotted against CXM concentration with linear fit as a solid line and 95% confidence interval of best-fit line as a dotted line, significant relationship between P1NP and CXM ( r = 0.50, p < 0.0001). (D) C-terminal telopeptide of type I collagen (CTX) concentration plotted against CXM concentration with linear fit as a solid line and 95% confidence interval of best-fit line as a dotted line, with a significant relationship between CTX and CXM ( r = 0.40, p < 0.0001). Eighty-three percent of total data points collected shown in plots C and D, data points above 2,500 CXM pg/mL excluded to better show relationship, all data points at all timepoints were used in linear fit analysis ( n = 159). (E) Pearson correlations between CTX, P1NP, and CXM at 0, 6, and 12 weeks ( n = 53 points/biomarker/week; p values for each biomarker pairing according to week: CTX - PINP: 0 = <0.001, 6 = 0.003, 12 = 0.01; CXM - CTX: 0 = 0.08; 6 = <0.001; 12 = 0.15; CXM - PINP: 0 = 0.01; 6 = <0.001; 12 = < 0.001). (F) Pearson correlation coefficients between CXM and 4 proteins associated with bone formation at 12 weeks, significant negative correlation between CXM and Leptin ( p = 0.005, n = 56–66 points/protein).