TLR4 knockout promoted fracture healing, reduced the number of osteoclasts, increased bone callus volume (BV) and callus mineralized volume fraction (BV/TV%) (P < 0.05), increased the maximum torque and torsional stiffness of callus (P < 0.05), reduced TNF-α, IL-1β and IL-6 expression (P < 0.01), and increased the expression levels of β-catenin, Wnt4, Wnt5B, PCNA and BMP-2 (P < 0.01).
The insulin-coated samples demonstrated significantly lower expression of the gene for interleukin 1β (p = 0.019) at 1 day, and significantly exhibited more periosteal callus (p = 0.029) at 3 weeks.