New generation of headgear for rugby: impact reduction of linear and rotational forces by a viscoelastic material-based rugby head guard

OBJECTIVES: In the aim to develop a usable and wearable head guard for rugby that could reduce impact energy and lessen the likelihood of concussive and subconcussive injury during play, a combination of viscoelastic materials was employed to develop a guard with similar dimensions to those currently used in international rugby. METHODS: The head guard was tested for impact energy reduction following linear acceleration, using drop tests, as required by World Rugby. The head guard was also subjected to pendulum tests, allowing acceleration to be simultaneously measured on two headforms, as well as repeated impacts to mimic ageing and repeated use. Impact following rotational acceleration was determined at two impact locations and at three impact velocities. RESULTS: The viscoelastic head guard (N-Pro) was shown to reduce linear impacts by up to 75% in comparison to the use of a commercially available rugby head guard and repeated impacts did not impair the attenuation of impact energy. Rotational impact energy was also reduced by an average of 34% across three speeds and two sites of impact test sites, in comparison to tested bare headforms. CONCLUSIONS: This heralds a new generation of soft-shelled headgear that could help reduce two primary risk factors in sports-induced mild traumatic brain injury: linear and rotational impacts to the head.