High G-Forces in Unintentionally Improper Infant Handling: Implications for Shaken Baby Syndrome Diagnosis

Abstract

IntroductionAbusive head trauma (AHT), commonly referred to as Shaken Baby Syndrome (SBS), is diagnosed in approximately 33 per 100,000 infants annually in the United States. Traditional diagnostic criteria for SBS include subdural, subarachnoid, and retinal hemorrhages. While intentional shaking is a known cause, the potential for similar forces acting on the head resulting from accidental trauma has not been fully explored. This study investigates the biomechanical forces on a model infants head during improper handling to determine if such forces could contribute to SBS without malicious intent. MethodsA realistic silicone infant model was equipped with an inertial measurement unit (IMU) to quantify head accelerations during two conditions: (1) placement of the infant model on a table with the head unsupported, and (2) manual shaking at maximum effort by 2 participants holding the model by the torso. Peak head accelerations were recorded for both conditions, and the results were analyzed for comparative assessment of the forces involved. ResultsThe average peak head acceleration when placing the infant model on a table with the head unsupported was +30,952.67 {+/-} 6,540.79 mg, with a range of +19,234.40 to +43,406.30 mg across trials. The average peak head accelerations during maximum effort shaking were significantly lower than placing the infant on the table, averaging 11,430.48 {+/-} 9,539.06,867 vs. 30,952.67 {+/-} 6,540.79 mg, p < 0.0001). There were no significant differences in head accelerations between participants when placing the infant model on the table with the head unsupported (p = 0.93) nor with shaking the baby with maximum effort (p = 0.97). DiscussionThe G-force in this study resulted in higher forces than experienced in an 18-mph car crash and a 5-mph bumper car collision. The study highlights that even accidental non-recommended handling of infants can result in high G-forces to the head, potentially leading to injuries similar to those observed in SBS. These findings highlight the necessity of supporting an infants head during handling and warrants caution against prematurely attributing physical abuse in SBS cases without considering unintentional causes.