A sagittal plane is an anatomical plane which divides the body into right and left parts. The plane may be in the centre of the body and split it into two halves (mid-sagittal) or away from the midline and split it into unequal parts (para-sagittal).
Most elements of Irish dancing occur in the sagittal plane.
Examples include:
The terms median plane or mid-sagittal plane are sometimes used to describe the sagittal plane running through the midline. This plane cuts the body into halves (assuming bilateral symmetry), passing through midline structures such as the navel and spine. It is one of the planes which, combined with the Umbilical plane, defines the four quadrants of the human abdomen.
The term parasagittal is used to describe any plane parallel to the sagittal plane. In practice, such a section is often referred to simply as a "sagittal" view because viewing is achieved along the sagittal axis (see below). Owing to the specific nature of its definition, only one true sagittal plane exists, and it corresponds to the "mid-sagittal" view. Be aware that the term "sagittal view" may be applied to any parasagittal section as well as the sagittal plane, as the parasagittal and sagittal axes are identical (parallel to the sagittal plane).
Specific named parasagittal planes include:
The midclavicular line crosses through the clavicle.
Other sagittal lines/planes include the lateral sternal and parasternal.
The term sagittal is derived from the Latin word sagitta, meaning "arrow". An image of an arrow piercing a body and passing from front (anterior) to back (posterior) on a parabolic trajectory would be one way to demonstrate the derivation of the term. Another explanation would be the notching of the sagittal suture posteriorly by the lambdoidal suture —similar to feathers on an arrow.
Sagittal axis or anterior-posterior axis is the axis perpendicular to the coronal plane, i.e., the one formed by the intersection of the sagittal and the transversal planes
Coronal axis, medial-lateral axis, or frontal axis is the axis perpendicular to the sagittal plane, i.e., the one formed by the intersection of the coronal and the transversal planes.
Extension and flexion are the movements of limbs within the sagittal plane.
Abduction and adduction are terms for movements of limbs within the coronal plane.
