Experiment and Dynamic Simulation of Cervical Tractions in Inclined and Sitting Positions

This study aims to validate the accuracy of a cervical traction therapy simulation model by comparing the intervertebral separations of six asymptomatic male adults when traction was applied to their cervical spines. The subjects were tested on two mechanical traction devices, representing the inclined and sitting positions. A total of 55 radiographic images of their cervical spines were taken before and during traction. The result showed statistically significant intervertebral space changes in the inclined position but the changes in the sitting position were not statistically significant. The observed changes of the cervical spine were used to adjust parameters of the traction therapy model, which contains a human model with cervical spine built with springs and dampers and two traction devices in inclined and sitting positions. A series of traction forces and traction angles were applied to the model to simulate the actual parameters used in the experiment and the new model was used to evaluate the two traction positions. The result suggested that inclined position creates greater intervertebral separations on the posterior sides. Differences in separations due to age were not observed in both positions. The result also suggested that the inclined position provides better control in positioning the separations at different spinal segments than the sitting position.