Patella (The Knee)

The patella or knee cap is the bone between the fibula and femur. Each leg has a patella to protect its knee joint. The patella serves two functions:

1. To protect the knee from physical trauma.
2. To enhance the leverage that the quadriceps tendon can exert on the femur, thereby increasing muscle efficiency.

The apex of the patella faces inferiorly and connects to the tibia tuberosity through the patella ligament that attaches to the anterior surface. The base of the patella faces superiorly and is the attachment point for the quadriceps tendon. 

The posterior surface of the patella contains the medial and lateral facets that articulate with the condyles of the femur. The lower posterior region of the patella has vascular canaliculi, small channels within the bone, which form the infrapatellar fat pad.

Knee Joint

This image shows the position of the patella relative to the articulation of the femur and the tibia.

This illustration of the knee joint shows the position of the patella relative to the articulation of the femur and the tibia.