Abstract
Aim
Previous studies of primary internal fixation of infected non-unions have reported high failure rates. Local antibiotic carriers and coatings have been advocated to reduce infection around implants and allow bone healing. We evaluated the effect of a calcium sulphate/hydroxyapatite antibiotic-loaded composite on bone healing and the eradication of infection in combination with internal fixation.
Method
Twelve cases of established infected non-union, with segmental bone loss of up to 1cm were treated using a multidisciplinary protocol. This included; excision, deep sampling, stabilisation, local and systemic antibiotics, and soft-tissue closure. We treated 5 femurs, 4 humeri, 1 tibia and 2 periarticular non-unions at the ankle. Mean age was 59.8 years (34–75) and 9 patients had systemic co-morbidities (C-M Type B hosts). 9 patients had single stage surgery, with 5 IM Nails and 4 plates. Three patients had planned second stage internal fixation after external fixation to correct deformity. Staph. aureus was the commonest pathogen (5 cases) with polymicrobial infection in 3 cases.
Results
All 12 patients were infection-free at a mean follow-up of 23 months (range 13–34 months). Union was achieved in 11/12 (92%) with the primary surgery alone. The single failure was the tibial case, who remains with an infection-free, stiff non-union.
Conclusion
This protocol offered good results, mainly with a single stage treatment. Primary internal fixation was possible in 9 cases, without recurrent infection. The combination of excision of infected dead bone and a high level of local antibiotics above the Minimum Inhibitory Concentration and Minimum Biofilm Eradication Concentration levels for common bacteria, allowed a high success rate in these difficult cases.
