Practical 1: Axes and Planes

Planes & Axes of Human Movement

Introduction to Anatomical Planes and Axes

Understanding human motion requires a three-dimensional perspective. Anatomical planes and axes provide a framework for describing and analyzing movement in the body. Each plane is a two-dimensional surface, and axes are lines perpendicular to these planes, allowing for precise description of movement directions.

• Axes are always perpendicular (at a 90° angle) to a plane and can be moved anywhere within the plane.

• Each plane is only associated with one axis. The relationship between a plane and its axis is crucial for understanding movement.

• To observe a plane, imagine looking at the body as if through a projector screen; the axis comes out from the screen.

• Rotation occurs along the axis, while movement occurs within the plane.

Fundamental movements refer to anatomical position-based motions associated with specific plane/axis pairs. For any given movement, its orientation determines the associated plane and axis.

The Anatomical Planes

• Sagittal Plane: Divides the body into right and left portions.

• Frontal (Coronal) Plane: Divides the body into anterior (front) and posterior (back) portions.

• Transverse (Horizontal) Plane: Divides the body into superior (upper) and inferior (lower) portions.

Diagram: The body can be visualized as intersected by these three planes, each providing a different perspective for analyzing movement.

The Anatomical Axes

• Medio-Lateral Axis: Runs horizontally from side to side; perpendicular to the sagittal plane.

• Anterior-Posterior Axis: Runs horizontally from front to back; perpendicular to the frontal plane.

• Superior-Inferior (Longitudinal) Axis: Runs vertically from top to bottom; perpendicular to the transverse plane.

Sagittal Plane & Medio-Lateral Axis

Definition and Orientation

The sagittal plane divides the body into right and left halves. Movements in this plane occur around the medio-lateral axis, which runs from side to side through the body.

Fundamental Movements in the Sagittal Plane

• Flexion: Decreases the angle between two body segments (e.g., bending the elbow or knee).

• Extension: Increases the angle between two body segments (e.g., straightening the elbow or knee).

• Anterior & Posterior Tilt: Refers to the pelvis tilting forward (anterior) or backward (posterior).

• Anterior & Posterior Tipping: Refers to the scapula tilting forward/downward (anterior) or backward/upward (posterior).

Examples: Flexion and extension at the shoulder, knee, and neck are classic sagittal plane movements.

Frontal (Coronal) Plane & Anterior-Posterior Axis

Definition and Orientation

The frontal plane divides the body into anterior and posterior portions. Movements in this plane occur around the anterior-posterior axis, which runs from front to back through the body.

Fundamental Movements in the Frontal Plane

• Abduction: Movement away from the midline of the body (e.g., raising the arms or legs sideways).

• Adduction: Movement toward the midline of the body.

• Right & Left Lateral Flexion: Bending the trunk or neck to the right or left.

• Right & Left Lateral Pelvic Tilt: Pelvis tilts so one side moves superiorly.

• Radial & Ulnar Deviation: Movement of the wrist toward the thumb (radial) or little finger (ulnar).

• Inversion & Eversion: Movement of the sole of the foot inward (inversion) or outward (eversion).

• Upward & Downward Rotation: Movement of the scapula so the glenoid cavity moves upward (upward rotation) or downward (downward rotation).

Examples: Abduction and adduction of the arms, lateral flexion of the trunk, and scapular upward/downward rotation.

Transverse (Horizontal) Plane & Superior-Inferior Axis

Definition and Orientation

The transverse plane divides the body into superior and inferior portions. Movements in this plane occur around the superior-inferior (longitudinal) axis, which runs vertically through the body.

Fundamental Movements in the Transverse Plane

• Medial (Internal) Rotation: Rotation toward the midline of the body.

• Lateral (External) Rotation: Rotation away from the midline of the body.

• Pronation & Supination: Rotation of the forearm so the palm faces down (pronation) or up (supination).

• Horizontal Abduction & Adduction: Movement of the arm or thigh in the horizontal plane away from (abduction) or toward (adduction) the midline.

Examples: Rotational movements of the head, trunk, and limbs, as well as pronation and supination of the forearm.

Summary Table: Anatomical Planes, Axes, and Fundamental Movements

Plane	Axis	Fundamental Movements	Examples
Sagittal	Medio-Lateral	Flexion, Extension	Biceps curl, knee extension
Frontal (Coronal)	Anterior-Posterior	Abduction, Adduction, Lateral Flexion	Jumping jacks, side bends
Transverse (Horizontal)	Superior-Inferior (Longitudinal)	Rotation, Pronation, Supination	Turning head, twisting trunk

Key Points and Applications

• Movements are described relative to anatomical position and the associated plane/axis.

• Understanding planes and axes is essential for analyzing joint motion, injury mechanisms, and exercise technique.

• Muscle contractions are not always required for movement; some motions can occur passively.

Example Application: In clinical and sports settings, knowledge of planes and axes helps professionals assess movement patterns, diagnose injuries, and design rehabilitation or training programs.