Tibia nonunions treated by interlocked nailing: increased risk of infection after previous external fixation.

Eighteen patients, mean age 36 years (range of 22-76 years), with tibia-shaft nonunions were treated with interlocked nailing. There were 12 nonunions originally treated with either cast, lag screws, plate, or Ender nails (nine closed, two open grade I and one grade II injury). The remaining six nonunions, all open fractures (five grade II and one grade III injury) initially received external fixation. After removal of the fixator, 72 days postinjury (range of 58-111 days), there was a delay of 218 days (range of 112-449 days) before the nailing procedure in those patients primarily treated with external fixation. All 12 nonunions not primarily treated with external fixation healed without complications after nailing within 17 weeks (range of 12-24 weeks). All six nonunions primarily treated with external fixation had temporary pin-tract infections, which healed after pin extraction. Two of the nonunions healed without any complication, whereas four developed intramedullary infection with the same bacteria as from the pin-tract site. Although the number of patients is small in this report, there is an apparently high incidence of intramedullary infection in the group originally treated with external fixation. The sequential procedure of external fixation followed by intramedullary nailing is, therefore, not recommended in the treatment of open tibia fractures.