Posterior

The term posterior is widely used in the field of anatomy to describe the relative location of structures or parts of the body. Also known as the dorsal side, it refers to the back or rear part of the human or animal body. This descriptor is essential for understanding and communicating the location of body parts in relation to one another, especially in clinical and educational settings.

Posterior view of human female

Definition

Posterior (Dorsal): Pertaining to the back or situated behind. For instance, the spine is posterior to the stomach.

Etymology

The word "posterior" derives from the Latin posterus, meaning "coming after". "Dorsal" originates from the Latin dorsum, signifying "the back".

Usage in Human Anatomy

In human anatomy, using "anterior" and "posterior" is more common when referencing the front and back of the body, respectively. However, in the context of four-legged animals, "dorsal" and "ventral" are more routinely utilized to describe back and belly sides.

Examples in human anatomy include:

• The scapula or shoulder blade is located on the posterior side of the body.
• The Achilles tendon is situated at the posterior part of the ankle.
• The occipital lobe of the brain lies in the posterior region of the cranial cavity.

Comparison with Other Anatomical Terms

Several terms help define the position of body structures in relation to one another:

• Anterior (or Ventral): Refers to the front or direction facing forward. In humans, the chest is anterior to the spine.
• Lateral: Positioned away from the midline of the body. The arms are lateral to the torso.
• Medial: Towards the midline. The nose is medial compared to the eyes.

Clinical Significance

Understanding and accurately using anatomical terms like "posterior" is critical in various professions, especially in medicine. Precise communication can impact:

• Diagnostic procedures, ensuring that the correct area of the body is examined or tested.
• Surgical interventions, where a specific direction might be needed to approach a structure safely.
• Physical therapy instructions, allowing therapists to guide patients through exercises more effectively.

In Other Organisms

In many animals, especially those that walk on four legs (quadrupeds), the term "dorsal" is often used instead of "posterior" to denote structures that are towards the backside. In fish, for example, the "dorsal fin" is the fin on the backside of the body.

See Also

• Anatomical terms of location
• Human anatomy
• Medicine
• Biology

Summary

Posterior or dorsal is back (example, the shoulder blades are located on the posterior side of the body).