We evaluated in 20 Japanese white rabbits the effects of tibial lengthening on tibial nerve conduction and intraneural blood flow at the end of lengthening. Both tibiae were distracted 1 mm per day. The distraction frequency was in 2 steps (0.5 mm/12 h) on the right side and in 120 steps (0.0083 mm/12 min) on the left. The rabbits were separated into 4 subgroups based on the percentage of lengthening: 0 (control), 10, 20, and 30 percent. In the 2-step group, nerve conduction was delayed at 20 and 30 percent lengthening, compared to the control group, while in the 120-step group, it was delayed only at 30 percent lengthening. Intraneural blood flow in the 2-step group was decreased at 10, 20, and 30 percent lengthenings, while in the 120-step group it was reduced at 30 percent lengthening. Our findings indicate that an increase in the frequency of distraction reduces the impairment of nerve function during bone lengthening.