Basic Terminology in Anatomy

Directional Terms

• Anterior vs. Posterior: Divides the body into front (anterior) and back (posterior).
• Ventral vs. Dorsal: Used for the torso or trunk. Also applied to the hand as volar (palm) and dorsal (back).
• Medial vs. Lateral: Toward the midline (medial) and away from the midline (lateral).
  • Example: Deltoid is lateral to the sternum.
• Superior vs. Inferior: Toward the head (superior) and toward the feet (inferior).
  • Example: Upper arm is superior to the hand.
• Cranial vs. Caudal: Toward the head (cranial); specifically towards the spine when using caudal.
• Superficial vs. Deep: Closer to the surface (superficial) and below the surface (deep).
  • Example: Flexor digitorum profundus is deeper than the flexor digitorum superficialis.

Movement Planes and Axes

• Sagittal Plane: Divides body into right and left. Movement: flexion/extension.
  • Axis: Frontal axis.
• Coronal (Frontal) Plane: Divides body into anterior and posterior. Movement: abduction/adduction.
  • Axis: Sagittal axis.
• Transverse (Horizontal) Plane: Divides body into upper and lower (superior/inferior). Movement: rotation.
  • Axis: Longitudinal (vertical) axis.

Imaginary Axes

• Sagittal Axis: Runs front to back.
• Frontal Axis: Runs side to side.
• Longitudinal/Vertical Axis: Runs top to bottom.

Degrees of Freedom

• Definition: Number of planes around a joint.
• Single Plane Movement: One degree of freedom (e.g., hinge joint).
• Three Planes Movement: Three degrees of freedom (e.g., glenohumeral joint, hip joint).
  • Movements: Flexion/extension (sagittal), abduction/adduction (frontal), internal/external rotation (transverse).

Practical Examples

• Sagittal Plane: Bicep curls, walking, squatting.
• Frontal Plane: Jumping jacks, snow angels, side bending.
• Transverse Plane: Checking mirrors, driving, spinning.

Summary

• Learning these terms is essential for understanding anatomy and will be used throughout the semester and OT curriculum.