Anterior knee pain

Anterior knee pain is pain that occurs at the front and center of the knee. It can be caused by many different problems, including:

Chondromalacia of the patella -- the softening and breakdown of the tissue (cartilage) on the underside of the kneecap (patella)
Runner's knee -- sometimes called patellar tendinitis
Lateral compression syndrome -- the patella tracks more to the outside part of the knee
Quadriceps tendinitis -- pain and tenderness at the quadriceps tendon attachment to the patella
Patella maltracking -- instability of the patella on the knee

Causes

Your kneecap (patella) sits over the front of your knee joint. As you bend or straighten your knee, the underside of the patella glides over the bones that make up the knee.

Strong tendons help attach the kneecap to the bones and muscles that surround the knee. These tendons are called:

The patellar tendon (where the kneecap attaches to the shin bone)
The quadriceps tendon (where the thigh muscles attach to the top of the kneecap)

Anterior knee pain begins when the kneecap does not move properly and rubs against the lower part of the thigh bone. This may occur because:

The kneecap is in an abnormal position (also called poor alignment of the patellofemoral joint).
There is tightness or weakness of the muscles on the front and back of your thigh.
You are doing too much activity that places extra stress on the kneecap (such as running, jumping or twisting, skiing, or playing soccer).
The groove in the thighbone where the kneecap normally rests is too shallow.
You have flat feet.

Anterior knee pain is more common in: