Etiology and fracture classification

Patellar fractures are usually caused by direct trauma because of kicks, collisions or during jumping activities.

Horses that compete over fixed fences or objects are most likely to suffer patellar fractures in conjunction with the stifle region impacting the obstacle.

Nearly all patellar fractures are articular. The degree of displacement is determined by disruption of the patellar fascia and/or traction from the patellar ligaments or the medial patellar fibrocartilage.
The fracture types diagnosed are:

1. Apical
2. Distal
3. Parasagittal
4. Sagittal
5. Transverse

There are also comminuted fractures of various configurations.