![]() ![]() Some individuals may also have additional (i.e., supernumerary) cervical ribs or lumbar vertebrae. The most common variations include sutural (wormian) bones, which are located along the sutural lines on the back of the skull, and sesamoid bones which develop within some tendons, mainly in the hands and feet. Individuals may have more or fewer bones than the average (even accounting for developmental stage) owing to anatomical variations. Some reliable sesamoid bones such as the pisiform are counted, while others, such as the hallux sesamoids, are not. In addition, the bones of the skull and face are counted as separate bones, despite being fused naturally. Therefore, the number of bones in an individual may be evaluated differently throughout a lifetime. Many small accessory bones, such as sesamoid bones, are not included in this count.Īs a person ages, some bones fuse, a process which typically lasts until sometime within the third decade of life. ![]() It is composed of 270 bones at the time of birth, but later decreases to 206: 80 bones in the axial skeleton and 126 bones in the appendicular skeleton. ![]() The human skeleton of an adult consists of around 206 bones, depending on the counting of sternum (which may alternatively be included as the manubrium, body of sternum, and the xiphoid process). ![]()
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