Bone flap management strategies for postcraniotomy surgical site infection

Surgical site infection (SSI) after a craniotomy is traditionally treated with wound debridement and disposal of the bone flap, followed by intravenous antibiotics. The goal of this study is to evaluate the safety of replacing the bone flap or performing immediate titanium cranioplasty.

All craniotomies at single center between 2008 and 2020 were examined to identify 35 patients with postoperative SSI. Patients were grouped by bone flap management: craniectomy (22 patients), bone flap replacement (seven patients), and titanium cranioplasty (six patients). Retrospective chart review was performed to identify patient age, gender, index surgery indication and duration, diffusion restriction on MRI, presence of gross purulence, bacteria cultured, sinus involvement, implants used during surgery, and antibiotic prophylaxis/ treatment. These variables were compared to future infection recurrence and wound breakdown.

There was no significant difference in infection recurrence or future wound breakdown among the three bone flap management groups (P = 0.21, P = 0.25). None of the variables investigated had any significant relation to infection recurrence when all patients were included in the analysis. However, when only the bone flap replacement group was analyzed, there was significantly higher infection recurrence when there was frank purulence present (P = 0.048).

Replacing the bone flap or performing an immediate titanium cranioplasty is safe alternatives to discarding the bone flap after postoperative craniotomy SSI. When there is gross purulence present, caution should be used in replacing the bone flap, as infection recurrence is significantly higher in this subgroup of patients.