- Patella
Infobox Bone
Name = Patella tendonismness
Latin =
GraySubject = 60
GrayPage = 255
Caption = Knee diagram
Caption2 =
Origins =
Insertions =
Articulations =
MeshName = Patella
MeshNumber = A02.835.232.043.650.624 |The patella or kneecap is a thick, triangularbone which articulates with thefemur and covers and protects the knee joint. It is the largestsesamoid bone in the human body. It is attached to thetendon of the quadriceps femoris muscle, which contracts to extend/straighten theknee . Thevastus intermedialis muscle is attached to the base of patella. Thevastus lateralis andvastus medialis are attached to lateral and medial borders of patella respectively.The patella is stabilized by the insertion of
vastus medialis and the prominence of the anterior femoral condyles, which prevent lateral dislocation during flexion. The retinacular fibres of the patella also stabilize it during exercise.The primary functional role of the patella is knee extension. The patella increases the
lever age that the tendon can exert on the femur by increasing the angle at which it acts.The patella ossifies between the ages 2-6 years. In some people it may be absent congenitally or hypoplastic. In 2% of the population there is a bipartite patella, which is usually asymptomatic. Direct trauma, however, may produce symptoms that mimic those of a fracture.
Regarding non-human animals, the patella is fully developed only in placental mammals; marsupials have only rudimentary, non-ossified patellae. [cite journal|author=Herzmark MH|title=The Evolution of the Knee Joint| url=http://www.ejbjs.org/cgi/reprint/20/1/77.pdf| accessdate=2007-11-17| journal=J Bone Joint Surg Am| year=1938| volume=20| pages=77–84]
ee also
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Patellar reflex
*Lateral retinaculum
=AdditionalReferences
mhm
External links
* [http://www.kneeguru.co.uk/KNEEnotes/node/900 The KNEEguru - educational site packed with knee content with sections on the patella]
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