Complications of cranioplasty following decompressive craniectomy for traumatic brain injury: systematic review and meta-analysis

Background Decompressive craniectomy (DC) is a common neurosurgical intervention for severe traumatic brain injury (TBI), as well as malignant stroke, malignancy and infection. DC necessitates subsequent cranioplasty. There are significant demographic differences between TBI and non-TBI patients undergoing cranioplasty, which may influence their relative risk profiles for infection, aseptic bone flap resorption (aBFR) and re-operation. Objective Perform a meta-analysis to determine the relative infection, aBFR and re-operation risk profiles of TBI patients as compared to other indications for DC. Methods A systematic review and meta-analysis was performed in accordance with the PRISMA guidelines. PubMed, MEDLINE, EMBASE and Google Scholar were searched until 26/11/2020. Studies detailing rates of infection, re-operation and/or aBFR in specific materials and the post-TBI population were included, while studies in paediatrics or craniosynostosis repair were excluded. Results Twenty-six studies were included. There was no difference in relative risk of infection between TBI and non-TBI cohorts (RR 0.81, 95% CI 0.57–1.17), with insignificant heterogeneity ( I 2 = 33%). TBI was a risk factor for aBFR (RR 1.54, 95% CI 1.25–1.89), with no significant heterogeneity ( I 2 = 13%). TBI was a risk factor for re-operation in the autologous sub-group (RR 1.49, 95% CI 1.05–2.11) but not in the alloplastic sub-group (RR = 0.86, 95% CI 0.34–2.18). Heterogeneity was insignificant ( I 2 = 11%). Conclusion TBI is a risk factor for aBFR and re-operation following cranioplasty. Use of an alloplastic graft for primary cranioplasty in these patients may partially mitigate this increased risk.