1. When studying various joints of body and analyze their movements, helpful to characterize according to specific planes of motion.
2. Plane of motion may be defined as imaginary two-dimensional surface through which limb or body segment is moved.
3. there are 3 specific, or cardinal planes in which various joint movements can be classified.
4. planes that divide body into 2 halves referred to-cardinal planes.
5. Cardinal planes are: sagittal, frontal, and transverse. (there are an infinite number of planes within each half that are parallel to the cardinal plane.
A) e.g. sit-ups involve spine-and performed in cardinal sagittal plane, aka MIDSAGITTAL or MEDIAN plane.
B) biceps curls and knee extensions performed in parasagittal planes, which are parallel to midsagittal plane.
C) Even thought these examples are not in cardinal plane, they are thought of as movements in sagittal plane.
6.) Although each joint movement can be classified as being in one of 3 planes of motion, our movements are usually not toally in one specific plane but occur as a combination of motions in more than one plane. These movements in the combines planes may be described as occurring in diagonal, or oblique, planes of motion.