The fabella is an accessory ossicle most always found in the lateral head of the gastrocnemius, rarely can occur at the medial head of gastrocnemius . It occurs in ~20% (range 10-30%) of the population .
The fabella can also be fibrocartilaginous in nature and is occasionally found in the medial head of the gastrocnemius. The fabella articulates with its respective (medial or lateral) femoral condyle.
History and etymology
Fabella is Latin for "little bean".