[Antibiotic-PMMA beads combined with external fixator for treating the infected fracture nonunion]

To investigate the effects of antibiotic-PMMA (polymethyl-methacrylate) beads combined with external fixator in treatment of infected fracture nonunion.

Twenty-two cases of infected fracture-nonunions were reviewed involving 20 male and 2 female with an average age of 34.68 years (ranging 21 to 74 years). The data consisted of 9 cases of tibial fractures, 2 distal fractures of the femur, 6 femoral shaft fractures, 3 intertrochanteric fracture of the femur and 2 humeral shaft fractures. The procedure included thorough debridement to wipe out dead bone and granulation tissue, then antibiotic-PMMA bead chains imbedded into the dead space. One week later, secondary debridement was performed, antibiotic-PMMA bead chains were changed according to result of bacterial culture and susceptibility test, and fractures were stabilized with external fixator. Three months after debridement, antibiotic-PMMA bead chains were taken out and bone graft with autogenous iliac cancellous bone chips was performed.

The mean follow-up period was 19.98 months (ranging 15 to 28 months). Infection was controlled in 20 cases. One tibial fracture and 1 intertrochanteric fracture of the femur needed repeated debridement 2 and 3 months after bone grafting respectively,because of infection recurrence and sinus formation. All 22 cases achieved bony union averaged 15.09 weeks after bone grafting with a range of 8 to 24 weeks.

Thorough debridement, imbedding antibiotic-PMMA bead chains combined with external fixator and staged bone grafting has proven to be effective and simple for treatment of infected fracture nonunion. The antibiotic bead delivers high tissue levels,obliterates dead space, aids bone repair.