From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Fabella with arrow.jpg
LatinOs fabella
Anatomical terminology
A 2019 study on increased prevalence of the fabella in humans

The fabella (Latin for little bean) is a small sesamoid bone found in some mammals embedded in the tendon of the lateral head of the gastrocnemius muscle behind the lateral condyle of the femur. It is an accessory bone, an anatomical variation present in 39% of humans.[1][2] Rarely, there are two or three of these bones (fabella bi- or tripartita). It can be mistaken for a loose body or osteophyte.

Although the fabella seems to have disappeared with the evolution of Hominidae, it reappeared in humans sometime after they diverged from chimpanzees. It is unknown whether it reappeared soon after this divergence, 5–7 million years ago, or more recently in human evolution .[3]

"The fabella can lead to posterolateral knee pain either due to cartilage softening (chondromalacia fabellae) or other osteoarthritic changes on its articular surface."[4]

See also[edit]


  1. ^ Berthaume, Michael A.; Di Federico, Erica; Bull, Anthony M. J. (April 17, 2019). "Fabella prevalence rate increases over 150 years, and rates of other sesamoid bones remain constant: a systematic review". Journal of Anatomy. Wiley. 235 (1): 67–79. doi:10.1111/joa.12994. PMC 6579948. PMID 30994938.
  2. ^ "Sore knee? Maybe you have a fabella". BBC News. April 19, 2019.
  3. ^ Sarin, Vineet K.; Erickson, Gregory M.; Giori, Nicholas J.; Bergman, A. Gabrielle; Carter, Dennis R. (1999). "Coincident development of sesamoid bones and clues to their evolution". The Anatomical Record. Wiley. 257 (5): 174–180. doi:10.1002/(SICI)1097-0185(19991015)257:5<174::AID-AR6>3.0.CO;2-O.
  4. ^ Dannawi, Z.; Khanduja, V.; Vemulapalli, K.; Zammit, J.; El-Zebdeh, M. (January 20, 2010). "Arthroscopic Excision of the Fabella –". Journal of Knee Surgery. 20 (4): 299–301. doi:10.1055/s-0030-1248063. PMID 17993073.

Further reading[edit]

External links[edit]