The knee works like a door hinge. It holds up the whole body when we stand, walk, run, or jump. Because it moves a lot, it gets a lot of pressure.
Everyday actions such as running, squatting, or playing can hurt the knee. The damage may involve soft parts like ligaments, the meniscus, or tendons, and sometimes even the bone.
When these parts are torn or broken, the knee can feel pain, swell, or become unstable. Getting help from a doctor early can stop the problem from getting worse.