What is an important principle when making a splint?

The principle of immobilizing the joint above and below the injury is crucial when making a splint. This ensures that the injured area remains stable, preventing further injury and reducing pain. By securing the joint above and below the site of the injury, the splint helps to restrict movement effectively, thereby aiding the healing process and minimizing the risk of complications, such as further damage to soft tissue or bones.

Other options, such as the need for the splint to be colorful or made of metal only, do not contribute to the functional effectiveness of the splint. Allowing movement contradicts the primary goal of a splint, which is to immobilize the injured area to promote recovery and protect it from additional harm.