Kneecap

: Often called "runner's knee," this is a common condition characterized by a nagging ache or sharp twinge under or around the kneecap, frequently aggravated by stairs, jumping, or sitting for long periods.

This is the most critical function. Without a kneecap, the quadriceps muscle pulls in a straight line down the leg. With a kneecap, the quadriceps tendon wraps around the bone, increasing the distance from the joint's axis. This creates a . Kneecap