[Treatment of complex bone nonunion with external skeletal fixation]

To summarize the experience in the treatment of 112 cases of complex bone nonunion from 1982 to 1999 in our department and introduce the technique of external skeletal fixation.

The two fragment ends of all cases were fixed under pressure with half-ring sulcated external skeletal fixator. Those cases complicated by bone defect or limb shortening were operated on with epiphysiotomy to restore the length of the limb in the period of compressive fixation or after the occurrence of bone union according to the condition of complicated infection and the length of the limb shortened.

The nonunion of the 112 cases was united eventually. The infection in 34 cases was eradicated. Bone union in cases without infection took 3 approximately 7 months (average 5.2 months) and in cases with infection took 5 approximately 11 months (average 5.5 months). The length of the limb in 11 cases with bone defect was restored in the same period of compressive external fixation and another 8 cases achieved after bone union. The length between the injured and healthy limbs was balanced.

When external skeletal fixation is employed to treat those troublesome cases of bone nonunion, the pins for fixation are inserted in sites far from the lesions and the non-united fragment ends are exposed only in the area without scars. Consequently, there is little interference with the blood circulation and the osteogenic potency of the fragment ends. The sclerotic bone tissue is not excised, the marrow cavity is not chased to be open and the fragment ends are only moderately modified. As a result, the stability of fixation is increased and further shortening of the limb avoided. External skeletal fixation using small pins with cross penetration results in plastic fixation and promotes bone healing. Bone lengthening with epiphysiotomy can restore the balance of the limbs.