Sesamoid bone Sesamoid bone In anatomy, a sesamoid bone () is a bone embedded within a tendon or a muscle. It is derived from the Latin word ("sesame seed"), due to the small size of most sesamoids. Often, these bones form in response to strain, or can be present as a normal variant. The kneecap is the largest sesamoid bone in the body. Sesamoids act like pulleys, providing a smooth surface for tendons to slide over, increasing the tendon's ability to transmit muscular forces. The sesamoid is a small nodular bone most often present embedded in tendons in the region of the
Occipitofrontalis muscle eyebrows and wrinkles the forehead. In humans, the occipitofrontalis only serves for facial expressions. In apes, however, the head is not balanced on the vertebral column, and apes therefore need strong muscles that pull back on the skull and prominent supraorbital ridges for the attachment of these muscles. Occipitofrontalis muscle The occipitofrontalis muscle (epicranius muscle) is a muscle which covers parts of the skull. It consists of two parts or bellies: The occipital belly, near the occipital bone, and the frontal belly, near the frontal bone. In humans, the occipitofrontalis only serves for facial expressions. Some sources consider the occipital