ABSTRACT
As described in many texts on human anatomy, the normal adult human skeleton is composed of 206 bones, which have macroscopically similar shape and structure in all individuals. However, upon closer examination, almost all skeletons exhibit some deviation from the norms developed from the study of anatomy. One such form occurs when bones fail to ossify where and when they should, leaving an opening in an unexpected area. Another is the accessory ossicle (small extra bone), formed when a single bone is divided into two or more segments. Similarly, sometimes bone parts do not join at the time expected for fusion during growth. Finally, a number of pathological conditions and other anomalies can appear in any part of the skeleton, which represent deviations from the norm.
