Anatomical Position: Definitions and Illustrations

Anatomical Position
Anatomical Positions.

Copyright Evelyn Bailey

 

The standard anatomical position is considered the reference position for a given organism. For humans, the standard position is at rest, standing erect while facing forward. Every other anatomical position is described with respect to this standard position.

Anatomical positions are important because they give us a frame of reference for describing the body. Similar to a compass, anatomical position gives us a universal way to describe the position of an organism. The concept of anatomical position is particularly important in medicine, as mistakes can occur if medical professionals do not have a shared point of reference for discussing patients' bodies.

Key Terms

  • Supine: a horizontal position with the face oriented up
  • Prone: a horizontal position with the face oriented down
  • Right lateral recumbent: a horizontal position with the right side oriented down
  • Left lateral recumbent: a horizontal position with the left side oriented down

Anatomical Positions

The four main anatomical positions are: supine, prone, right lateral recumbent, and left lateral recumbent. Each position is used in different medical circumstances.

Supine Position

Supine
Copyright Evelyn Bailey

Supine position refers to a horizontal position with the face and upper body facing up. In the supine position, the ventral side is up and the dorsal side is down.

A number of surgical procedures use the supine position, particularly when access to the thoracic area/cavity is needed. Supine is the typical starting position for human dissection as well as for autopsies.

Prone Position

Prone
Copyright Evelyn Bailey

Prone position refers to a horizontal position with the face and upper body facing down. In the prone position, the dorsal side is up and the ventral side is down.

A number of surgical procedures use the prone position. It is most commonly used for surgeries requiring access to the spine. The prone position also helps to increase oxygenation in patients with respiratory distress.

Right Lateral Recumbent Position

Right Lateral Recumbent
Copyright Evelyn Bailey

The word "lateral" means "to the side," while "recumbent" means "lying down." In the right lateral recumbent position, the individual is lying on their right side. This position makes it easier to access a patient's left side.

Left Lateral Recumbent Position

Left Lateral Recumbent
Copyright Evelyn Bailey

The left lateral recumbent position is the opposite of the right lateral recumbent position. In this position, the individual is lying on their left side. This position makes it easier to access a patient's right side.

Trendelenburg and Fowler's Positions

Fowler's and Trendelenburg
Fowler's Position and Trendelenburg Position. Copyright Evelyn Bailey

Other common positions include Trendelenburg's and Fowler's positions. Fowler's position has a person sitting up (straight or with a slight lean), while Trendelenburg's position has the person in a supine position with the head about 30 degrees lower than the feet.

Fowler's position is named after George Fowler, who originally used the position as a way to help with peritonitis (inflammation of the membrane lining of the abdominal wall). Trendelenburg's position is named after Friedrich Trendelenburg and is often used in surgery and to improve venous blood return to the heart.