What are planes of motion?
Consider a plane to be a sheet of paper. This sheet can be held at any angle, and is essentially a 2-dimensional surface. All movements of the body can be placed within one of these planes. All movements, or motion, can be described as being within one of these planes.
Axes of Motion
An axis of motion is the point about which a rotational movement occurs. The axis of any motion is perpendicular to the plane in which that motion takes place. In the human body, the axis of a movement is the joint at which the movement is taking place.
Types of planes
- Sagittal: a sagittal plane divides a body, or object, into left and right parts. It is a vertical plane, perpendicular to the ground (or surface the body is on) and runs through the body from front (anterior) to back (posterior). Sagittal plane motions occur around the coronal axis.
- Frontal: a frontal plane divides the body into front (anterior) and back (posterior). It is also a vertical plane, perpendicular to the ground, or surface the body is on. The plane runs through the body from left to right. Frontal plane movements occur around the anterior-posterior axis.
- Transverse: this is a horizontal plane, parallel to the ground, or surface the body is on. It separates the body into top (superior) and bottom (inferior). It runs through the body not only from left to right, but also from front to back. Transverse plane movements occur around the longitudinal axis.
- Oblique: since the 1st three types of planes have very strict angles of description, and not all motions can take place in those very strict confines, there must be another plane available. These planes are called oblique planes. They run anywhere between the other three planes, and are essentially a combination of 2, or even all 3.
Body vs Planes
The movements of the body can all be described using planes. But, not only on an individual basis; i.e. selecting a movement at one joint, and describing its plane and axis. The overall result of individual movements can result in gross movement, which can also be described using planes. An example of this would be how a combination of movements of the pelvis (rotation), hips (flexion, extension, rotation), knees (flexion, extension) and ankles (dorsiflexion and plantar flexion), which can all be described in their individual planes, produce the gross movement of walking. Walking can also be described by the plane in which it takes place.
Hip Flexion and Extension occurs in the sagittal plane.
Hip abduction and adduction will occur in the frontal plane
Hip rotation will occur in the transverse plane.
Of course, this is not limited to walking. In almost all situations where the body is moving, it is a combination of movements at different joints, resulting in the gross movement. Once again, these can all be broken down to their individual pieces, or it can be looked at as the whole movement.