Flashing mouthguards to flag instant HIA needed at World Cup

Mouthguards that flash red to indicate players require a head injury assessment will make their debut at this month’s Women’s Rugby World Cup before being rolled out across the elite game.

It is the next stage in the development of “instrumented” mouthguards that measure the force a player experiences in a collision and issues an alert if pre-set thresholds are exceeded.

Currently, a pitchside doctor receives an alert, triggering a mandatory 12-minute head injury assessment.

A player is then checked over and performs a series of coordination and cognition tests to diagnose a concussion.

However a light-emitting diode (LED) embedded in the mouthguard that will be used at the Women’s World Cup will also flash red to alert on-pitch officials more quickly and raise awareness.

Referees at the tournament will stop play on sight of a flashing mouthguard and send the player for an assessment, rather than a pitchside doctor waiting for a break to remove them.

While the thresholds for rotational force are the same for both male and female players at 4,500 radians, an acceleration alert is triggered at 75G for men and 65G for women.

It is believed that women are more susceptible to concussion as their game contains fewer head acceleration events, but a similar rate of concussion to the men’s game.

Instrumented mouthguards, which were first used in the international game in WXV in 2023, are not mandatory.

Some players have medical reasons for not wearing them, while others have concerns over the use of their data or a Bluetooth unit within their mouth.

However World Rugby says there has been “full opt-in” from players set to compete at the 2025 Rugby World Cup, with two players willing to wear the mouthguards, but unable to do so due to dental braces.