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a bone formed after birth in a tendon where it passes over a joint, for example, the patella.
Synonym(s): os sesamoideum [TA]
Etymology: Gk, sesamon, sesame, eidos, form
any one of numerous small round bony masses embedded in certain tendons that may be subjected to compression and tension. The largest sesamoid bone is the patella, which is embedded in the tendon of the quadriceps femoris at the knee.
sesamoid bone(1) A bone located in the tendons of the flexor hallucis brevis on the plantar aspect of the foot, which help redistribute and attenuate force over the first metatarsal head during the toe-off portion of gait or propulsion.
(2) A membranous bone formed in a tendon in response to joint stress (e.g., patella).
ses·a·moid bone(ses'ă-moyd bōn) [TA]
A bone formed after birth in a tendon where it passes over a joint (e.g., the patella).