Patella

Kneecap, bone covering knee joint

The patella (pl.: patellae or patellas), also known as the kneecap, is a flat, rounded triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint. The patella is found in many tetrapods, such as mice, cats, birds, humans, and dogs, but not in whales, or most reptiles. In humans, the patella is the largest sesamoid bone (i.e., embedded within a tendon or a muscle) in the body.

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