Distraction osteogenesis for the treatment of post traumatic complications using a conventional external fixator. A novel technique.

PURPOSE: To evaluate the clinical results of post traumatic complications treated by the author's own technique using an AO/ASIF conventional external fixator (without special distraction device).

MATERIALS AND METHODS: There were 70 patients (77 limbs) with an average of 26.8 years (range, 4-54). There were 33 femurs, 43 tibias and one ulna. The following post traumatic complications were treated: 14 limb shortening, 20 nonunion, 28 malunion 14 infected open fractures with bone loss and 1 chronic osteomyelitis. Linear lengthening was performed in 29 limbs, acute de-rotation and subsequent lengthening in two limbs, gradual angular correction in six limbs, combined gradual angular correction and subsequent lengthening in 10 limbs, combined acute angular correction and subsequent lengthening in eight limbs and 22 limbs with bony defects were treated with the technique so-called "bone transportation". All of the limbs were treated with an AO/ASIF conventional external fixator, using the author's own technique with distraction rate of 1 mm in one step on alternate day (1 mm/48 h).

RESULTS: A new bone formation in the distraction gap was achieved in 73 of the 77 limbs. Four cases without consolidation were successfully treated with an iliac bone graft combined with plating or reapplication of the external fixator. Average new bone formation was 5.6 cm (range, 1-17 cm). The average follow-up period was 10.8 months (range, 1-71 months) after removal of the fixator. The average healing time was 244.7 days (range, 60-836 days) and the healing index was 50 days/cm (range, 17-100 days). In the group with associated angular deformity the mean correction was 18.5 degrees (range, 10-40).

CONCLUSIONS: The author's technique of distraction osteogenesis, using a conventional external fixator combined with a distraction rate of 1 mm/48 h (1 mm/step) adequately treated the post traumatic complications. No extra equipment was needed other than readily available AO/ASIF fixation systems. The described technique, using an AO/ASIF fixator as a lengthening apparatus was simple and cost-effective.