Management of partial bone defect by a bone transport method using unilateral external fixator

Objective To evaluate the effect of a bone transport method using unilateral external fixator in treatment of partial bone defect.Methods Three patients with partial bone defect were reviewed,including 2 males and 1 female,and whose ages were 50,50,and 24 years,respectively.The defects were at medial part of the left proximal tibia in 2 cases.In the first case,the defect was 5 cm in length,1/3-2/3 of transverse diameter in width,with a 5 cm×3 cm skin loss.In the second case,the defect was 6 cm in length and 3 cm in width.For the remaining patient,the bone defect was located in lateral part of the right femur,which was 13 cm in length,1/3-2/3 of transverse diameter in width,with a 15 cm×7 cm scar on it.After debridement of the wound,the Orthofix's limb reconstruction external fixation system was mounted medially,initially with 2-3 HA coated screws in the middle clamp to anchor the near cortex of the segment to be transferred.A partial corticotomy was performed with multiple drill hole technique.The gradual segment transport was started 2 weeks after the operation at a rate of 1 mm/d,4 times/d.Results The follow-up time was 14,28 and 24 months,respectively.The external fixator was removed 8 and 6 months after the osteotomy in 2 patients,when radiographs demonstrated bony union of the docking site as well as mature consolidation of the generated callus.The range of motion of hip,knee,ankle on the injured side was similar to the uninjured side.The segment was unable to be transported successfully in the femur,because the compressiondistraction device was misused.Two months after the first operation,the osteotomy was performed at the same site for the second time.The frame was removed at 10 months after the second osteotomy when the new bone formed well and the fracture healed at the docking site.The patient was able to stand independently and walk with a stick at 17 months after the osteotomy.At the latest follow-up,there was no sign of osteomyelitis.Conclusion Bone transport method using unilateral external fixator is a practical option to treat partial bone defect.In addition to shorten the period with fixator,it can avoid malunion and donor injury. Key words: Ilizarov technique;  External fixators;  Osteogenesis, distraction