When attending to an injured motorcycle rider in an accident, it is important **not to remove their helmet**. This is because the helmet protects the head, and removing it could **worsen any injuries** the rider may already have.

- **Head injuries**: Head injuries are one of the leading causes of death in two-wheeled vehicle accidents. The helmet is a crucial passive safety element that can save lives by protecting the head during an accident.

- **Neck protection**: Moving or removing the helmet risks causing sudden movements in the neck, which could worsen existing injuries. It is essential to keep the neck protected and avoid any unnecessary movement.

- **General rescue guidelines**: In accident situations, it is recommended not to move the injured unless absolutely necessary for their safety. This includes not removing the helmet, as it could worsen the injuries.

For these reasons, it is essential to leave the helmet on until emergency services arrive, as they are trained to handle the situation safely.