The patella is a large sesamoid bone located in the tendon of the insertion of the quadriceps muscle of the pelvic limb.
The patella is roughly triangular, presenting:
- A base proximally, roughened for muscular attachment
- An apex distally
- A lateral and a medial border (this one extended medially in horse, ox and cows by the fibrocartilage process)
- An articular surface caudally (divided in horses by a sagittal ridge that occupied the groove between the two rides of the trochlea)
- A cranial surface palpable under the skin
Anatomy of the Horse - Sixth Edition - Klaus Dieter Budras - Schlütersche