The patella is the kneecap, the bone sitting over the front of the knee. Plural = 'patellae'.

patella with patellar tendon and quads tendon

The patella from the side, showing its relationship to the femur bone and tibia bone.

patella within the tendon of the quads muscle

The patella is contained within the tendon of the quads muscle and the whole muscle-bone-tendon complex is known as the 'extensor mechanism'.

patella from above

A stable patella is contained within the walls of the underlying groove of the femur.


The extensor mechanism

The patella is a 'sesamoid bone', contained within a tendon, and subject to the forces that pass through that tendon and its related muscles. The part of the tendon below the patella is called the patellar tendon, while the part above is called the quads tendon, but it is all part of a single functional structure. When the knee straightens or extendes, the forces go through all parts of the extensor mechanism.


Knee anatomy intro

This page offers a quick overview of key anatomical structures of the knee joint.

The patella - important anatomical relationships

The kneecap or patella is part of a chain of structures that help to straighten the knee.

Explaining how the kneecap glides within the underlying groove of the femur bone.

How to perform patellar mobilisations

A brief but high value eBook - fully illustrated - showing how to keep the tissues around the kneecap supple.

Knee bones from above

Simple illustrations to give a birds' eye view of the knee bones.

Knee bones from side

Bony anatomy of the knee, in simple terminology.




Patellar position in patients with patellofemoral syndrome as characterized by anatomo-radiographic study. Franco BAFM, Sadigursky D, Daltro GC. Rev Bras Ortop. 2018 Jul 7;53(4):410-414.

Acute traumatic patellar dislocation. Duthon VB. Orthop Traumatol Surg Res. 2015 Feb;101(1 Suppl):S59-67.


A simple explanation of the patella, and why it is important.


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