Introduction
Are you interested in healthcare but repeatedly find yourself flabbergasted by complicated anatomical terms? Look no further. I’ve compiled a concise list of the most important directional terms in human anatomy. While the list won’t instantly turn you into an anatomy connoisseur, it will give you a basic understanding of the most common terms used to define locations of the body. Once you’ve committed them to memory, you’ll begin to recognize them in practice and apply your new knowledge.
Standard Anatomical Position
Coordinated Universal Time (UTC) is globally agreed to be the standardized reference point for time. Similarly, standard anatomical position is the standardized reference position for anatomy. All of the terms you will learn today are derived from the standard anatomical position. In standard anatomical position, a person is standing straight with the legs slightly spread and the palms facing forward.
Directions
Anterior
The front side of the body is called the anterior. Your belly button is on the anterior side of your body. The tibialis anterior is the muscle that runs near your shin bone on the front side of your leg.
Posterior
The back side of the body is called the posterior. Note that anterior and posterior have opposite definitions. Your heel is located on the posterior side of your foot. The tibialis posterior is a muscle that makes up a part of your calf and helps you stand on your toes!
Superior
Superior refers to the upward direction or towards the head. Your neck is superior to your abdomen. The serratus posterior superior is a thin muscle situated on your upper back. Notice how directional terms can be paired to be more precise!
Inferior
Inferior refers to the downward direction or away from the head. Note that inferior and superior have opposite meanings. Your shoulders are inferior to your head. The serratus posterior inferior is located in the lower back and helps you twist your body.
Lateral
Lateral means away from the middle or to the side of the body. Your ears are lateral to your eyes. The vastus lateralis muscle is a part of your quadriceps and is located on the exterior sides of your thighs.
Medial
Medial means toward the midline or center of the body. Note that medial and lateral have opposite meanings. I like to think of the “median”, which means the middle value in mathematics. Your chest is medial to your arms. The medial plantar nerve passes through the interior side of your foot and gives nerve supply to the medial foot.
Distal
A structure that is far from the center of the body is distal. I use the heart as the center point of the body to help myself conceptualize this term better. Your toes are distal to your ankle. The distal phalanges are the small bones at the tips of your fingers and under your nails.
Proximal
A structure that is close to the center of the body is proximal. Note that distal and proximal have opposite meanings. I always tell myself that distal things are a distance away, while proximal things are in proximity. Your elbow is proximal to your wrist. The proximal phalanges are the bones that extend from your knuckles to the first finger joints.
Superficial
Superficial means close to the surface or shallow. Your hair is superficial to your scalp while your scalp is superficial to your skull. A superficial cut to your skin can typically be cared for without stitches because it doesn’t injure muscle or fat tissue.
Deep
Deep means further into the body or inwards (I saved the easy one for last!). Note that superficial and deep have opposite meanings. Your heart is deep to your pectoral muscle. The deep brachial artery is a branch of the brachial artery that runs near the bone in your arm.
Don’t forget to quiz yourself here when you’re done reading!