For femoral shaft fracture, damage control orthopaedics entails primary external fixation and subsequent conversion to an intramedullary device (IMN). Sub-clinical contamination of external fixator pin sites is common and it is argued that such an approach risks subsequent local infective complications. We aimed to determine the rate of wound infection following DCO procedures and primary IMN for femoral fracture stabilisation.

Retrospective analysis of a prospectively assembled adult patient database was carried out. Inclusion criteria were femoral #, New Injury Severity Score (NISS) above 20 and survival more than 2 weeks. Two groups, damage control (DCO) and early total care (ETC) (Primary Nail), were formed. Contamination was positive culture from the wound or fixator pin-sites without clinical infection. Superficial infection was a combination of positive bacterial swabs and local or systemic signs of infection. Deep infection was any case requiring surgical intervention with a sub-group requiring removal of femoral metal work (ROMW) also defined.

173 patients met the criteria for inclusion, with 192 fractures (19 bilateral). The mean follow up was 19 months. Patients in the damage control group were more severely injured than those undergoing primary intramedullary nailing (NISS 36 vs 25, p 0.001). There were also more severe (Grade 3 A,B or C) local soft tissue injuries in this group (p 0.05). 98 of the 111 DCO patients underwent subsequent IMN. Others either died without conversion being appropriate, or it was elected to complete treatment with external fixation. The mean time of exchange an ex/fix to a nail was 14.1 days.

Though contamination rates were higher in the DCO group (12.6% vs 3.7%, p 0.05), there was no excess of infective complications (11.1% vs 10.8%). Contamination increased significantly in patients who underwent conversion to IMN after 14 days. Grade 3 open injury was significantly associated with infection irrespective of treatment.

This study demonstrates that infection rates following DCO for femoral fractures are not significantly different to those observed following primary intramedullary nailing. Whilst the overall risk of deep infection in the DCO group did not show any correlation with the timing of converting the external fixator to a nail, the risk of contamination was higher in patients where the exchange nailing was performed after a period of 2 weeks.