Also called: kneecap
The patella, or kneecap, is the largest sesamoid bone in the body. It sits within the quadriceps tendon in front of the knee and articulates with the patellar surface of the femur. It increases the leverage of the quadriceps and protects the front of the knee joint.
| Type | Sesamoid bone. |
|---|---|
| Location | Anterior aspect of the knee, in the quadriceps tendon. |
| Landmarks | Base, apex, anterior surface, articular surface with medial and lateral facets. |
| Articulations | Femur (patellofemoral joint). |
| Muscle attachments | Quadriceps femoris tendon at the base; patellar ligament at the apex. |
3D model: BodyParts3D (CC BY 4.0), adult male reference anatomy. Highlighted structure shown with nearby bones for context.
The patella improves the mechanical advantage of the quadriceps by increasing the distance of the tendon from the knee joint axis.
A sesamoid bone embedded in the quadriceps tendon.
It increases the leverage of the quadriceps muscle and protects the front of the knee.
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