Planes of Reference

White and Folkens (2005) emphasized that in anatomy and physiology, it is useful to know the relative positions of the body parts. These serve as the primary basis in determining and understanding the regions of the body. He also emphasized that the failure to comprehensively understand these terms will lead to the failure to give correct diagnosis to patients. With this, the following are the common terms for spatial orientation, based on White and Folkens’ book The Human Bone Manual. (It is important to note that these terms usually come in pairs (usually, one term is the direct opposite of the other.)

Anterior refers to the position towards the front of the body, whereas posterior refers to the position towards the back of the body. Deep refers to the position away from the body surface, while superficial refers to the position towards the body surface. The term “central,” refers to the area located centrally, while “peripheral” means located in the periphery. Superior pertains to the area towards the top, while inferior is towards the bottom of the body. Medial means towards the midline and lateral means towards the side or away from the midline. To add, the term “median” is directly in the midline. Proximal means towards the original point and distal means away from the original point.

Other terms include the following. The prefix “contra-“ means on the opposite side, while the prefix “ipsi-“ means on the same side. Dorsal means towards the back while ventral is towards the belly. External means on the outside, while internal means on the inside. Extrinsic means coming from the outside, while intrinsic pertains to something coming from the inside. The term for the position while lying down on the belly with the face down is prone, whereas the term for lying down on the back with the face up is supine.