Background: Serious adverse events such as cervical artery dissection (CAD) have been reported to occur following cervical spine manipulation therapy (cSMT). To investigate the relation between these events, we utilized an animal model to determine if vertebral arteries with a suspected susceptibility factor (wall lesion) could be injured further by cSMT. Methods: Lesions to the vertebral artery wall were created by angioplasty in 10 anesthetized canines. Resulting injury dimensions were quantified using intravascular ultrasound before and after cSMT. Student's t were performed to assess the significance of changes in arterial dimension. Results: Statistical analysis demonstrated that the pre-cSMT and post-cSMT lesions did not differ significantly in their length, area or volume (p > 0.05). Conclusions: In this animal model, cSMT did not alter the dimensions of pre-existing vertebral artery lesions.