We report the effect of dynamization timing on healing rates when treating tibial fractures with the Dynamic Axial Factor (Orthofix, registered trademark). Sixty-nine patients with 71 fresh tibial fractures were grouped retrospectively for age, Gustilo and Anderson wound grading, site of tibial fracture and presence of an intact fibula or stable fibular fracture. Pairs were then generated chronologically to compare healing rates in those patients dynamized before 4 weeks with those dynamized after this time. This resulted in 22 pairs of patients; the other fractures could not be paired. Their healing times were compared using a paired t-test and were found to be significantly quicker in the group dynamized within the first 4 weeks (P < 0.05) and we therefore recommend that this should be routine practice.