Kin and Bio: Terminology & Planes

Terminology - Spatial Descriptors

  • Superior vs Inferior: terms used to describe vertical position relative to the body or a structure.

    • Superior: toward the head or upper part.

    • Inferior: toward the feet or lower part.

  • Anterior vs Posterior: directional terms relative to the front of the body.

    • Anterior: toward the front.

    • Posterior: toward the back.

  • Medial vs Lateral: relative to the midline of the body.

    • Medial: toward the midline.

    • Lateral: away from the midline.

  • Proximal vs Distal: described with respect to proximity to the origin/point of attachment.

    • Proximal: closer to the origin or point of attachment.

    • Distal: farther from the origin or point of attachment.

  • Cranial/Cephalad vs Caudal: directional terms toward the head vs toward the tail.

    • Cranial/Cephalad: toward the head.

    • Caudal: toward the tail.

  • Ventral vs Dorsal: ventral is belly/front surface; dorsal is the back surface.

  • Prone vs Supine: body position relative to the face.

    • Prone: lying face down.

    • Supine: lying face up.

  • Contralateral vs Ipsilateral:

    • Contralateral: on opposite sides of the body.

    • Ipsilateral: on the same side of the body.

Anatomical Terms - Flexion, Extension, Abduction, Adduction

  • Flexion: Movement that decreases the angle between two bones or two parts of the body. Ventral surfaces are approximated.

  • Extension: Movement that increases the angle between two bones or two parts of the body. Ventral surfaces move apart.

  • Abduction: Movement of the distal surface (limb/digit) away from the midline.

  • Adduction: Movement of the distal surface (limb/digit) towards the midline.

Anatomical Terms - Cont’d: Lateral Flexion and Rotation

  • Lateral Flexion: Movement away from midline on the axial skeleton (Head and Trunk).

  • Rotation: Turning around a central longitudinal axis.

    • Internal (Medial) Rotation: Rotation towards midline.

    • External (Lateral) Rotation: Rotation away from midline.

Visual cues for Lateral Flexion and Rotation

  • Lateral flexion to the right (example)

  • Rotation

  • Lateral rotation

  • Medial rotation

Anatomical Terms - Cont’d: Pronation, Supination, Protraction, Retraction

  • Pronation: Turning palm downwards/posteriorly.

  • Supination: Turning palm upwards/anteriorly.

  • Protraction: Anterior motion of the scapula.

  • Retraction: Posterior motion of the scapula.

Anatomical Terms - Cont’d: Dorsiflexion, Plantar Flexion, Inversion, Eversion

  • Dorsiflexion: Bringing the dorsal surface of the foot upwards (toes up, heel down).

  • Plantar Flexion: Pushing the dorsal surface downwards (toes down, heel up).

  • Inversion: Turning the plantar (sole) of the foot inwards.

  • Eversion: Turning the plantar (sole) of the foot outwards.

Osteokinematics - Fundamental Positions

  • Osteokinematics: the study of movement of bones relative to the body (bone movements).

  • Fundamental concepts:

    • Plane: A plane is a dimension in space.

    • Axis: An axis is a straight line around which an object rotates.

    • An axis is perpendicular to its plane.

    • Fundamental movements move parallel to the plane.

Planes and Axes: Sagittal Plane

  • Sagittal Plane: Passes from the front to the back of the body; creates a left and right side of the body.

  • Movements in the Sagittal Plane: Flexion, Extension.

  • Axis associated: Frontal (Horizontal) axis or mediolateral axis.

  • Notes from the diagrams: axis terminology may be described as

    • “Frontal Horizontal axis” or “mediolateral axis.”

Planes and Axes: Frontal (Coronal) Plane

  • Frontal Plane: Passes through the body from one side to the other; creates a front and back side.

  • Movements in the Frontal Plane: Abduction, Adduction, Lateral Flexion.

  • Axis associated: Sagittal (Horizontal) axis or anteroposterior axis.

Planes and Axes: Horizontal (Transverse) Plane

  • Horizontal (Transverse) Plane: Passes through the body horizontally; creates a top and bottom.

  • Movements in the Horizontal Plane: Rotation, Internal Rotation, External Rotation.

  • Axis associated: Vertical (Longitudinal) axis.

Visual and Nomenclature References

  • Visual cues in pedagogy suggest relationships between planes and their axes:

    • Frontal plane

    • Sagittal plane

    • Horizontal axes

    • Vertical axis

Bi- and Tri-axial Motion: Circumduction and Horizontal Movements

  • Biaxial or Triaxial motion: involves more than one plane.

  • Circumduction: Circumduction is a triplanar movement (combination of movements in multiple planes).

  • Horizontal movements include:

    • Horizontal Adduction or Flexion

    • Horizontal Abduction or Extension

    • Horizontal Abduction & Adduction

    • Horizontal Abduction

Center of Gravity (COG)

  • Center of Gravity (COG):

    • Point at which all three cardinal planes intersect.

    • The body’s weight distributes in all directions.

    • Shifts as the body moves.

    • Important for balance, injury prevention and successful activities.

Additional notes and clarifications

  • The three cardinal planes are used to describe movement in the body: Sagittal, Frontal (Coronal), and Horizontal (Transverse).

  • An axis is always perpendicular to its plane and movement occurs parallel to the plane.

  • The definitions above align with common anatomical terminology used in kinesiology and clinical mechanics.

  • Some slide content appears with typographical artifacts (e.g., "Jud", scattered letters). The core concepts remain: planes, axes, and corresponding movements.

  • When describing movements, visualize the body from the side (sagittal), from the front (frontal), or from above (horizontal) to determine which plane and axis are involved.

  • Practical implications: understanding planes and axes aids in analyzing movement efficiency, injury risk, and rehabilitation design.

extAxis⊥extPlaneext{Axis} \perp ext{ Plane}
extSagittalPlane<br>ightarrowextLeft−Rightsidesofthebodyext{Sagittal Plane} <br>ightarrow ext{Left-Right sides of the body}
extAxisforSagittalPlane=extFrontal(Horizontal)axisormediolateral axisext{Axis for Sagittal Plane} = ext{Frontal (Horizontal) axis} \text{or} \text{mediolateral axis}
extAxisforFrontalPlane=extSagittal(Horizontal)axisoranteroposterior axisext{Axis for Frontal Plane} = ext{Sagittal (Horizontal) axis} \text{or} \text{anteroposterior axis}
extAxisforHorizontalPlane=extVertical(Longitudinal)axisext{Axis for Horizontal Plane} = ext{Vertical (Longitudinal) axis}

Quick quick-reference summary

  • Planes: Sagittal, Frontal, Horizontal (Transverse).

  • Movements per plane: Flexion/Extension (Sagittal); Abduction/Adduction, Lateral Flexion (Frontal); Rotation, Internal/External Rotation (Horizontal).

  • Key terms: Pronation, Supination, Protraction, Retraction; Dorsiflexion, Plantar Flexion; Inversion, Eversion.

  • Special motions: Circumduction (Circumduction is triplanar).

  • Balance concept: Center of Gravity (COG) depends on body position and movement; critical for safe performance and injury prevention.