Limb-threatening injuries of the distal lower extremity in the pediatric population are fortunately rare but are being seen with increasing frequency, coinciding with the surging popularity of light motorcycles and all-terrain vehicles, which have few age and licensing restrictions in many states. The microsurgical management of these injuries in children has some unique features, but has not previously been the subject of a separate study. 12 patients between the age of 3 and 18 were treated at the University of Kentucky Hospital between 1989 and 2002 for severe open fractures or avulsive injuries of the distal lower extremity. All patients underwent wound debridement followed by bony stabilization and free muscle flap transfer. 9 out of 12 patients had a fracture requiring fixation. In 5 patients, internal hardware was used, in 4 patients external fixation was used. In the external fixation group, bone gaps ranged from 1 to 6 cm; three of these patients underwent subsequent cancellous bone grafting and one underwent shortening and Ilizarov bone lengthening. There were 6 latissimus dorsi flaps, 3 rectus abdominis flaps, 3 gracilis flaps, and 1 iliacus muscle flap. Early venous congestion was seen in three cases requiring a return to the operating room. Flap loss occurred in one patient and the limb was successfully salvaged with a second flap. There was one bony nonunion in the external fixation group which was successfully treated with subsequent internal fixation and bone grafting. Primary bony union was achieved in all cases in the internal hardware group. Follow-up ranged from 8 months to 14 years (mean 31 months). All limbs were successfully salvaged. 11 of 12 patients were ambulating independently at the time of follow-up; one patient who is undergoing Ilizarov lengthening has a partial weight-bearing status. Growth disturbance resulting in limb length discrepancy was seen in one patient. Illustrative cases and a treatment algorithm will be presented, taking into account the unique considerations in this population, which include choice of fixation, management of a large bone gap, flap choice, postoperative care, prevention of growth disturbances, and treatment of late sequelae. There is a significant role for the microvascular surgeon in the management of limb-threatening injuries in children, and if the unique features of this population are considered a high rate of limb salvage and good function can be expected.