Decompressive craniectomy in severe traumatic brain injury: a scoping review of contemporary evidence (2020–2025)

Abstract Background Decompressive craniectomy (DC) is a life-saving measure in severe traumatic brain injury (TBI), but its long-term functional outcome and the time of subsequent cranioplasty remain debated. Recent evidence indicates that cranioplasty can have a neurorestorative effect beyond the simple restoration of anatomy. Objective To map recent evidence (2020–2025) on DC and cranioplasty in adult severe TBI, focusing on timing, functional outcomes, complications, and survival. Methods A scoping review was conducted following PRISMA-ScR guidelines. PubMed, Google Scholar, and Cochrane Library were searched for English-language original research published from January 2020 to January 2025. Studies involving adult patients (≥ 18 years) with severe TBI undergoing DC, with or without subsequent cranioplasty, were included. Data were extracted on study design, sample size, timing of cranioplasty, functional outcomes, mortality, and complications. Risk of bias was assessed using the ROBINS-I tool. Results Five studies (one randomized controlled trial, four observational cohorts; n = 108–408) were included. Across included observational studies, earlier cranioplasty (variably defined as ≤ 2–3 months post-DC) was frequently reported to be associated with improved neurological function and rehabilitation engagement, without a proportional increase in complications. The RESCUE-ASDH trial found no statistically significant difference in mortality between DC and craniotomy (32.2% vs. 30.2%); early cranioplasty independently improved long-term survival (HR 0.65, 95% CI 0.42–0.97). Complication profiles, including infection and hydrocephalus, were comparable between early and delayed cranioplasty when patients were appropriately selected. Heterogeneity existed in timing definitions, outcome measures, and follow-up durations, highlighting the need for standardized reporting. Conclusion DC remains a critical life-saving procedure in severe TBI, and Early cranioplasty (≤ 90 days) is frequently reported to be associated with improved functional recovery and survival, without significantly increasing major complications. Clinical decisions should be individualized based on patient stability, radiological findings, infection risk, and rehabilitation potential. Standardized definitions and prospective trials are needed to optimize timing and outcomes.