Objective: To determine the load-limiting capabilities of protective neck collars used in football through dynamic impact testing.
Design: A 50th-percentile male Hybrid III dummy was used in 48 dynamic impact tests comparing The Cowboy Collar, Bullock Collar, and Kerr Collar. A control and each collar were tested at two velocities (5 m/s and 7 m/s), three impact locations (front, top, and side of the helmet), and two shoulder pad positions (normal and raised).
Setting: Research laboratory.
Interventions: None. Independent variables were the neck collars, impact velocity, and shoulder pad position.
Main Outcome Measurements: In addition to range of motion, upper and lower neck forces and moments were measured.
Results: With the top impact location, it was found that the Kerr Collar and Bullock Collar reduced head accelerations and force transmission through the neck. With the front impact location, all the collars reduced lower neck moment. The Kerr Collar was also capable of reducing the lower neck force and upper neck moment. With the side impact location, the Kerr Collar substantially reduced lower neck moment.
Conclusions: These reductions in loads correlate with the degree to which each collar restricted the motion of the head and neck. By restricting the range of motion of the neck and redistributing load to the shoulders, neck loads can be effectively lowered.