Charts of 70 patients with 72 nonunions of the tibial shaft were reviewed, identifying 39 aseptic and 33 infected nonunions. Most nonunions started as an open fracture (76%), although 4 of the 12 patients with closed fractures became infected following surgical treatment. Seven patients (all of the septic group) had a below-knee amputation as their only procedure; amputation was eventually necessary for three other patients. In total, 90% of the aseptic nonunions healed, as did 79% of infected nonunions not amputated at the first procedure. The average time from injury to union was approximately 36 months for both aseptic and infected nonunions. Numerous complications occurred during treatment of tibial nonunions, the most common (61%) being angulation of greater than 5 degrees in at least one plane.