Can antibiotic impregnated cement nail achieve both infection control and bony union in infected diaphyseal femoral non-unions?

BACKGROUND: Infected non-union is complex and debilitating disorder affecting orthopaedic surgeon and patient in terms of cost and time. Many methods are described in the literature for treatment of infected non-union. Local high concentration of antibiotic and mechanical stability of antibiotic cement impregnated intramedullary nail (ACIIN) proves cost and time effective. Recently it was suggested that ACIIN can achieve both union and infection control in infected non-unions with bone gap less than 4cm. The aim of our study was to investigate this hypothesis and study the outcome of antibiotic cement impregnated intramedullary nail in term of both infection control and osseous union.

MATERIALS AND METHODS: We retrospectively studied 21 patients with infected diaphyseal femoral non-union. Inclusion criteria were bone gap less than 4cm after debridement and more than 1 year follow-up of the case. ACIIN prepared using K nail was used as primary procedure after adequate debridement. Infection control and osseous union was judged on the basis of clinical, radiological and haematological parameters. All patients were followed up with an average follow-up of 20.23±3.65 months (range 14-28 months).

RESULTS: Infection control was achieved in all 21 patients at end of 12 months follow-up, out of which 16 patients had osseous union and infection control without any secondary procedure. Of the remaining 5 patients: two patients had good infection control but had broken ACCIN due to non-compliance to weight bearing protocol. One patient underwent exchange nailing and plate augmentation whilst the other underwent simple exchange nailing, One more patient who had infection control but had persistent non-union had to undergo exchange nailing and augmented plating to achieve union. One other patient required debridement and implant removal and attained union and fifth patient required two additional debridements to control infection after which the fracture united. Apart from above 5 cases there were two further complications of knee stiffness.

CONCLUSION: In infected non-union with bone gap less than 4cm, ACIIN can achieve both infection control and osseous union in significant number of cases. All such cases should be primarily operated with aim to achieve this outcome and use of thicker nail and ensuring proper compliance from patients regarding weight bearing will improve the outcomes.