The knee is a joint
that joins the thigh bone (femur) to the top of the shin bone (tibia). It is made
up of bones,
, and tendons. These parts work together to make the legs bend, straighten,
and swivel. A knee injury can damage one or more parts of the knee.
What Causes Knee Injuries?
Teens may injure a knee in a fall or accident. Active and athletic teens might
have overuse knee injuries.
These happen when someone trains too much or makes repetitive motions involving the
Osteochondritis dissecans: when a small piece of bone in the knee loses blood
supply and breaks off
of one of the fluid filled sacs that cushion the knee.
What Are the Signs & Symptoms of a Knee Injury?
The signs and symptoms of a knee injury depend on the cause. Most knee injuries
cause pain. A knee injury may also lead to the knee feeling weak, "giving way,"
or "locking." Someone with a knee injury might not be able to fully bend
or straighten the knee. The injured knee may be swollen or bruised.
How Are Knee Injuries Diagnosed?
To diagnose a knee injury, health care providers ask about how the injury happened
and what symptoms it causes.
The health care provider will do a physical exam that includes pressing on the
knee and legs and moving them in certain ways. These tests can show what part of the
knee is injured.