The lamb was used as an in vivo experimental analogue of abusive head trauma (AHT). An OpenSim computational model of the lamb was developed and used to interpret biomechanical data from shaking experiments. Sagittal plane acceleration components of the animal’s head during shaking were used to provide in vivo validation of the model. Results demonstrated that peak accelerations occurred when the head impacted the torso and produced acceleration magnitudes exceeding 200 m∙s-2. The computational model demonstrated good agreement with the experimental measurements and was able to reproduce the extreme accelerations that occur during impact. The biomechanical results demonstrate the utility of using the OpenSim modelling framework to describe infant head kinematics in AHT.