Standard anatomical position in human anatomy - The standard anatomical position is the reference position for anatomical location terms. - It is used to standardize the position of appendages in relation to the main body of the organism. - In the standard anatomical position, the human body is standing erect and at rest. - The limbs are placed in positions reminiscent of the supine position imposed on cadavers during autopsy. - The feet are together or slightly separated, and the arms are rotated outward with palms forward.

Implications of limb positions in the standard anatomical position - The positions of the limbs have important implications for directional terms in those appendages. - The penis in the anatomical position is described in its erect position and lies against the abdomen. - The dorsal surface of the penis is actually anterior when the penis is flaccid. - Limb positions help avoid confusion in terminology when referring to the same organism in different postures. - For example, even if the elbow is flexed, the hand remains distal to the shoulder.

Standard anatomical position of the skull (Frankfurt plane) - The Frankfurt plane is the agreed-upon anatomical position of the human skull. - It is a position in which the lower margins of the orbits and the upper margins of the ear canals lie in the same horizontal plane. - The Frankfurt plane approximation is based on the position the head would be in if the subject were standing upright and facing forward. - It is used for comparison of human skulls with those of other species, particularly hominids and primates. - The Frankfurt plane is not considered the anatomical position for most non-primate species.

History of the Frankfurt plane - The Frankfurt plane was established at the World Congress on Anthropology in Frankfurt am Main, Germany in 1884. - It was decreed as the anatomical position of the human skull. - The plane passes through the inferior margin of the left orbit and the superior margin of each ear canal. - The alternate spelling 'Frankfort plane' is also widely used. - The Frankfurt plane is also referred to as the auriculo-orbital plane.

Standard anatomical position in other animals - For dogs, the standard anatomical position has the abdomen ventral with each paw standing on the supporting surface. - The standard anatomical position may vary in different animal species. - The Frankfurt plane can be used as a reference point in related fields, such as prosthodontics. - The Frankfurt-Mandibular plane Angle (FMA) is the angle formed at the intersection of the Frankfurt plane with the mandibular plane. - The standard anatomical position is important for comparative anatomy studies.