Patella

Function

The body's largest sesamoid bone, buried in the quadriceps tendon. It lifts the tendon away from the knee's axis, boosting quadriceps leverage by roughly a third and shielding the joint's front.

Landmarks

• Base
• Apex
• Medial and lateral facets
• Articular cartilage (thickest in the body)

Articulations (joints)

• Femoral trochlea (patellofemoral joint)
• Patellar tendon (quadriceps to tibia)

Clinical relevance

Patellar dislocations run lateral, especially in teenage girls; chondromalacia patellae grinds the joint's record-thick cartilage behind kneecap pain.