Frequency of transcalvarial brain matter herniation in depressed skull fractures and its association with clinical, hematological, and injury-related radiological factors

Objective: To assess the frequency of transcalvarial herniation of brain matter in depressed skull fractures (DSF), and to evaluate the clinical, radiological, and hematological factors associated with such herniation. Methodology: This retrospective observational cohort study included patients who presented with depressed skull fractures between January 2024 and April 2026 at the Department of Neurosurgery, Unit-I, Punjab Institute of Neurosciences, Lahore, Pakistan. Chi-square tests for categorical variables and Mann-Whitney U tests were used to assess the association with transcalvarial brain matter herniation in DSF. Results: Among 60 cases of DSF, brain herniation was present in 36.70% (22). The mean age of the cohort was 25.65±13.11 years, with male predominance (78.30%, 47). The median presenting GCS was 14 (14-15). Radiological signs of raised ICP were present in 51.70% (31). The most common mechanism of injury was road traffic accident (RTA; 78.30%, 47). Brain herniation along the DSF was present in 36.70% (22). The most common locations were frontal (53.30%, 32). In the brain herniation group, the median depth of the fragmented segment was 20.0 (19.7-28.5), and the fractured segment median diameter was 39.5 (30.0-40.0). The presenting Glasgow Coma Scale score (GCS) was higher in patients with transcalvarial herniation (p-value 0.026). Whereas the midline shift (MLS; p-value 0.043) and fractured segment diameter (p-value 0.010) were both significantly higher in the non-herniation group. Conclusion: Transcalvarial herniation of brain matter was present in 36.67% of cases of DSF. DSF patients with transcalvarial herniation had higher GCS. Midline shift and fractured segment diameter were significantly higher in the patients without herniation.