Understanding Bilateral Skull Fractures in Infancy: A Retrospective Multicenter Case Review

Background Bilateral skull fractures in infancy often raise suspicion for abuse. Nevertheless, literature suggests that they may occur accidentally. However, empiric data are lacking. Objective This multicenter retrospective review aimed to characterize bilateral skull fractures in a large sample. Participants and Setting Medical records for infants younger than 24 months with bilateral skull fractures involving hospital consultation with a child abuse pediatrician (CAP) were reviewed from 2005 to 2020 at 13 nationally represented institutions. Methods Standardized data collection across institutions included historical features, fracture characteristics, and additional injuries, as well as the CAP's determination of accident versus abuse. Pooled data were analyzed for descriptive and bivariate analyses. Results For 235 cases, 141 were accidental, and 94 abuse. The majority occurred in young infants, and a history of a fall was common in 70% of cases. More than 80% involved both parietal bones. Bilateral simple linear fractures were more common in accidental cases, 79% versus 35%, whereas a complex fracture was more frequent in abuse cases, 55% versus 21% (P < 0.001). Almost two thirds of accidental cases showed approximation of the fractures at the sagittal suture, compared with one third of abuse cases (P < 0.001). Whereas focal intracranial hemorrhage was seen in 43% of all cases, diffuse intracranial hemorrhage was seen more in abuse cases (45%) than accidents (11%). Skin trauma was more common in abusive than accidental injury (67% vs 17%, P < 0.001), as were additional fractures on skeletal survey (49% vs 3%, P < 0.001). Conclusions A fall history was common in bilateral skull fractures deemed accidental by a CAP. Most accidental cases involved young infants with biparietal simple linear fractures, without skin trauma or additional fractures. A skeletal survey may aid in the determination of accidental or abusive injury for unwitnessed events resulting in bilateral skull fractures in infants.