Treatment of metaphyseal fractures of the tibia by the Ilizarov external fixator

PURPOSE: This external fixation was used for 46 of 60 cases of proximal tibial metaphyseal fractures, over a 10 years period. The choice of an external fixation was determined by the poor reputation of internal fixation for even complex closed fractures. The reasons for the choice of the Ilizarov device were: the possibility of fitting the fixation pins close to the knee joint if necessary, the circular nature of the system, and finally the possibility of adding an intrafocal mounting (I.F.M.) which can bring the displaced bone fragments together using shaped blockstops pins. The program theoretically foresaw an initial sequence using external fixation until bone continuity was achieved, followed by a complementary plaster for one or two months. MATERIALS: 7 of the 46 fractures were lost for follow-up. Of the remaining 39 cases, there were 5 early complications: one knee septic arthritis which led to stop the method before the second month. Each of these 5 failures were due to improper use of the method. 34 cases have been followed for more than two years. RESULTS: 29 cases of consolidation of which 3 initial displacements were wrongly considered as acceptable. There was no case of displacement while the fixation was in place. There were 5 nonunions: 2 at the diaphyseal level in long metaphyso-diaphyseal fractures, 2 were comminutive metaphyseal fractures in which the fixation had been removed by error before the third month. With this fixation, neither the traumatic opening, nor the presence of a fibular fracture significantly affected consolidation. The healing period was however longer when the fracture was more extensive and comminutive. The bone gaps were treated by interfocal mounting (I.F.M.) but loss of bone stock persisted; they affected the occurrence of nonunion. CONCLUSION: Each failure of the method is explained by its improper use. The Ilizarov fixation is an excellent mechanical response to these fractures: on condition that the technical rules are respected, that an intrafocal mounting is used to remove interfragmentary gaps, and that the fixator is kept in place long enough, according to the size and comminutive nature of the fracture. This fixation is reliable in these conditions but does not compensate intrafocal bone loss exceeding 40 per cent of the metaphyseal bone mass.