Overview
This lecture explains key anatomical directional terms, providing definitions, memory tricks, and examples to help describe locations and relationships within the human body.
Standard Anatomical Position
- The standard position is standing upright, head and eyes forward, arms at sides with palms forward, legs parallel, and feet flat.
- "Right" and "left" always refer to the patient's own sides.
Medial & Lateral
- Medial: Toward the midline (middle) of the body.
- Lateral: Away from the midline, toward the sides.
- Example: The nose is medial to the eyes; the eyes are lateral to the nose.
- Can be used for both external and internal body structures.
Superior & Inferior
- Superior: Above or toward the head; also called cranial.
- Inferior: Below or away from the head; also called caudal.
- Example: The eyes are superior to the mouth; the mouth is inferior to the eyes.
- Used to describe both external and internal anatomical relationships.
Anterior & Posterior
- Anterior: Toward the front of the body; also called ventral.
- Posterior: Toward the back of the body; also called dorsal.
- Example: The patella is on the anterior leg; the elbow is on the posterior arm.
Proximal & Distal
- Proximal: Toward the trunk or point of attachment.
- Distal: Away from the trunk or point of attachment.
- Example: The elbow is proximal to the hand; the hand is distal to the elbow.
- Applied to limbs and tubular structures like the colon.
Superficial & Deep
- Superficial: Closer to the surface of the body.
- Deep: Further away from the body surface.
- Example: Skin is superficial to ribs; lungs are deep to ribs.
Unilateral & Bilateral
- Unilateral: Involving one side of the body.
- Bilateral: Involving both sides of the body.
- Example: Rash on one arm is unilateral; rash on both arms is bilateral.
Ipsilateral & Contralateral
- Ipsilateral: On the same side of the body.
- Contralateral: On opposite sides of the body.
- Example: Injuries on same arm are ipsilateral; on opposite arms are contralateral.
Key Terms & Definitions
- Standard Anatomical Position — Universal body stance used for reference.
- Medial — Toward the body’s midline.
- Lateral — Toward the sides of the body.
- Superior (Cranial) — Toward the head.
- Inferior (Caudal) — Toward the feet or tail.
- Anterior (Ventral) — Toward the front.
- Posterior (Dorsal) — Toward the back.
- Proximal — Near the body’s trunk or a structure’s origin.
- Distal — Farther from the trunk or origin.
- Superficial — Closer to body surface.
- Deep — Further from body surface.
- Unilateral — One-sided.
- Bilateral — Affecting both sides.
- Ipsilateral — Same side.
- Contralateral — Opposite side.
Action Items / Next Steps
- Review the linked notes and images from the website for visual reinforcement.
- Re-watch previous videos on body planes and sections for more detail if needed.