The higher rate of anastomotic failure in avulsion injuries has been attributed mostly to the uncertainty in determining the uninjured vessel segment suitable for anastomosis and resection past a proximal branch that has been proposed to achieve good arterial flow. A graded, longitudinal, microarterial traction model in rats has been used to examine the histopathologic aspects of the extent of vascular injury and its association with the proximal side branch. Additionally, anastomoses were performed following traction, and thromboses rates were determined. Results indicated a more proximal vessel injury with increasing rates of traction and, although the vessel segment proximal to the side branch was spared, up to a certain degree of traction, the injury extended beyond this point with more aggressive traction force. Consistently increasing rates of thromboses, significantly higher than the control group, were demonstrated. This model may be of use in further studies on the efficacy of various antithrombotic agents.