When learning anatomy it is important to know directional terms in order to help understand the position of a structure relative to another. Most directional terms can be grouped into pairs that have an opposite meaning Ie. anterior (front) and posterior (back).
It is also a good idea to understand the planes of the body which are imaginary flat surfaces running through the body. Below is a chart explaining directional terms followed by a chart explaining body planes.
|Directional Term||Definition||Usage Example|
|Superior (Cephalic, Cranial)||Toward the head or upper part of the structure||Your knee is superior to your ankle.|
|Inferior||Away from the head or the lower part of the structure||Your elbow is inferior to your shoulder.|
|Anterior||Nearer to or at the front of the body||Your sternum is anterior to your heart.|
|Posterior||Nearer to or at the back of the body||Your esophagus is posterior to the trachea. (windpipe)|
|Medial||Nearer to the midline||Your ulna is medial to your radius.|
|Lateral||Further from the midline||Your lungs are lateral to your heart.|
|Intermediate||Between two structures||Your transverse colon is intermediate between the ascending and descending colons.|
|Ipsilateral||On the same side of the body as another structure||Your gallbladder and ascending colon are ipsilateral.|
|Contralateral||On the opposite side of the body from another structure||Your ascending and descending colons are contralateral.|
|Proximal||Nearer to the attachment of a limb towards the trunk. Near to the origin of a structure.||Your humerus is proximal to your radius.|
|Distal||Further from the attachment of a limb from the trunk. Farther from the origin of a structure.||Your phalanges are distal to your carpals.|
|Superficial (external)||Toward or on the surface of the body||Your ribs are superficial to your lungs.|
|Deep (internal)||Away from the surface of the body||Your ribs are deep to the skin of your chest and back.|
- Sagittal Plane – the vertical plane that divides the body or organ into left and right sides. (Not necessarily at the center line of the body)
- Midsagittal/Median plane – When a plane passes through the midline of the body or organ and divides it into equal left and right sides
- Frontal/Coronal plane – Divides the body or organ into anterior (front) and posterior (back)
- Transverse/Horizontal plane – Divides the body into superior (upper) and inferior (lower) portions.
- Oblique plane – An oblique plane passes through the body or organ at an angle.