Predictive factors for bone flap infection after cranioplasty

Bone flap infection is often experienced as a complication of cranioplasty. The aim of this study was to investigate predictors of graft infection, including patient-specific and surgery-specific factors. We retrospectively reviewed cases at our institution who underwent cranioplasty following craniectomy for traumatic brain injury, epidural hematoma, subdural hematoma, intracranial hemorrhage, cerebral infarction, subarachnoid hemorrhage, arteriovenous malformation, and bone flap infection after craniotomy. A total of 192 patients were included in this analysis. The graft infection rate was 8.3% (16/192). Smoking (odds ratio [OR] 3.09, 95% confidence interval [CI] 1.03-12.24; p = 0.04), allergy (OR 6.15, 95% CI 1.50-17.31; p < 0.01), and body temperature on postoperative day 1 (OR 2.57, 95% CI 1.14-5.78; p = 0.02) were found to be independent predictors for graft infection. Based on receiver operating characteristic analysis, a body temperature on postoperative day 1 higher than 38.0 degrees C was selected as the optimal cut-off value for predicting infection after cranioplasty. The sensitivity and specificity were 68% and 72%, respectively. Smoking, allergy, and body temperature on postoperative day 1 predicted complications leading to graft infection. Patients with a fever of 38 degrees C or higher on day 1 after cranioplasty should be carefully monitored for graft infection.