External fixation to intramedullary nailing for femoral and tibial fractures: an eleven-year cohort study at a level I trauma center.

PURPOSE: To identify factors that contribute to the incidence of postoperative complications following staged treatment of femoral and tibial fractures with external fixation (EF) and intramedullary nailing (IMN).

METHODS

This retrospective cohort study involved patients with tibial and/or femoral fractures temporarily immobilized using EF, followed by IMN. Patient characteristics, types of injury, treatments, and outcomes were recorded. Primary outcomes were pin tract infection (PTI) and fracture-related infection (FRI).

RESULTS

The study had 103 patients involving 119 fractures: 73 tibial (61.3%) and 46 femoral (38.7%). Of these, 44.5% were open. 31.1% of the EFs were implanted by an orthopedic trauma (OT) specialist. In femoral fractures, OT specialists placed the pins a mean 78.2 mm from the fracture site, versus just 37.3 mm by non-OT surgeons (p < 0.01). This difference was not observed in the tibia. The average time of EF was 12.6 ± 7.8 days. PTI occurred in seven cases (5.9%), on average 14.9 ± 10.9 days after EF placement. FRI occurred in nine patients (7.6%): two in the femur (4.5%) and seven in the tibia (10.6%). All FRIs occurred in cases where the EF had been implanted by a surgeon without specialization in OT (p = 0.03). FRI was more frequent in patients with prior PTI than in those without (57.1% vs. 4.5%, respectively; p < 0.01).

CONCLUSION

PTI was a risk factor for FRI after IMN of tibial and femoral fractures. Surgeon specialization in OT was a protective factor against FRI, probably related to pin placement further from the fracture site.