A splint is a stiff support used to keep an injured bone or joint from moving while it heals. When someone breaks their arm or sprains their wrist, doctors often apply a splint to hold everything in place, like putting scaffolding around a damaged building while repairs happen inside. The splint might be made of wood, metal, plastic, or even cardboard wrapped with bandages.

Splints have been used for thousands of years. Ancient Egyptians created splints from tree bark and linen. Today's splints work the same way: they prevent the injured area from bending or twisting, which gives bones time to knit back together and ligaments time to heal. Without a splint, an injury might move and become worse.

You can make an emergency splint from almost any rigid material. If someone injures their leg on a hike, you might use a straight stick and cloth to create a makeshift splint until help arrives. The key is keeping the injury stable and protected.

A splint differs from a cast in that splints can be removed and adjusted, while casts are hard shells that completely surround the injury and must be cut off after healing is complete.