Repeated whole-body vibration exposure induces prolonged mechanical hyperalgesia & increased spinal COX-2: A novel rat model

Whole-body vibration (WBV) has been linked to chronic back pain but the mechanisms of its development are unknown, as is how biomechanical contributions modulate the pain response. An animal model of WBV was developed in which rats were exposed to 7 days of either 5Hz or 15Hz vibration. WBV induced immediate sensitivity (i.e. pain) that was sustained for 7 days after the cessation of the WBV exposure. There was no difference in the pain response between the two vibration frequencies. Increases in the inflammatory mediator, COX-2, were also induced following painful WBV in the lumbar spinal cord, suggesting a potential mechanism for the chronic pain.