Sprains.~--In a similar manner the ligaments which hold the bones together, in a joint, are sometimes torn or over-stretched.

Such an accident is called a sprain.

A sprain is a very painful accident, and a joint injured in this way needs to rest quite a long time so that the torn ligaments may grow together.
~10.

Bones out of Joint.~--Sometimes the ligaments are torn so badly that the ends of the bones are displaced, and then we say they are put out of joint.

This is a very bad accident indeed, but it often happens to boys while wrestling or playing at other rough games.
~11.~ Children sometimes have a trick of pulling the fingers to cause the knuckles to "crack." This is a very foolish and harmful practice.