Cineradiographic study of football helmets and the cervical spine.

A total of 16 men (4 professional football players, 5 high school athletes, and 7 hospital personnel) was studied by cineradiography to evaluate the possible roles of the posterior rim of the football helmet in causing neck injuries. The men ranged from tall elongated neck individuals to short chunky neck individuals. Moving picture (16-mm) films were produced from a series of lateral view cineradiograms that were taken to document the path and position of the posterior rim of the helmet relative to the spinal column as the subject moved his head from the fully flexed to the fully extended positions under several loading conditions. Five different helmets, all from different companies, were used in the studies. No contact existed at any time between the posterior rim of any of the five helmets worn and the fourth cervical vertebral spinous process; in fact, it did not come close to the spinous process of vertebrae C1 through C6. The notion of the posterior rim of the helmet being capable of striking the cervical spine about the C4 to C5 level is without foundation.