<Li> In the neck--Although the hyoid bone is free floating, it is not technically a sesamoid bone . All sesamoid bones form directly from the connective tissue found in tendons and ligaments . By contrast, the hyoid bone forms from a cartilaginous precursor like most other bones in the body . </Li> <Li> In the ear--the lenticular process of the incus is a sesamoid bone and therefore is considered the fourth ossicle of the middle ear . </Li> <Ul> <Li> One or both of the sesamoid bones under the first metatarsophalangeal joint (of the great toe) can be multipartite--in two or three parts (mostly bipartite--in two parts). (See the X-ray photograph of the foot on the right .) </Li> <Li> The fabella 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 a variant of normal anatomy and present in humans in 10% to 30% of individuals . The fabella can also be mutipartite or bipartite . </Li> <Li> The cyamella is a small sesamoid bone embedded in the tendon of the popliteus muscle . It is a variant of normal anatomy . It is rarely seen in humans, but has been described more often in other primates and certain other animals . </Li> </Ul> <Li> One or both of the sesamoid bones under the first metatarsophalangeal joint (of the great toe) can be multipartite--in two or three parts (mostly bipartite--in two parts). (See the X-ray photograph of the foot on the right .) </Li>

Define a sesamoid bone using the patella as an example