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Anatomy and Planes: Video Notes Review (Vocabulary)

Anatomy: Planes, Positions, Terms, Movements and Body Cavities

Anatomy: Overview

  • Etymology: The term 'anatomy' derives from ancient Greek meaning 'to dissect' (Ana: a part – tom: cut).
  • Definition: Anatomy is the descriptive study of different body parts.

Subdivisions of Anatomy

  • Gross Anatomy (Macroscopic Anatomy): Study of the human body with the naked eye. It can be studied as:
    • Systemic Anatomy: study system by system (skeletal, muscular, nervous, CVS, etc.).
    • Regional Anatomy: organization of the body into parts (thorax, abdomen, head & neck, etc.).
  • Microscopic Anatomy: Study of various body structures with the help of a microscope.
  • Applied / Clinical Anatomy: Application of anatomical knowledge to medical and surgical practice.
  • Radiological Anatomy: Study of anatomy of various organs with plain or contrast radiography (X-ray, CT scan, MRI).
  • Developmental Anatomy: Study of prenatal developmental changes in an individual.

Importance of Anatomy

  • Essential for medical professionals to have sound knowledge and clear understanding of basic anatomical terms.

Methods of Studying Anatomy

  1. Dissection
  2. Surface Anatomy
  3. Microscopic Anatomy
  4. Embryology (developmental)
  5. Endoscopic Anatomy
  6. Gross (Macroscopic) Anatomy
  7. Functional Anatomy
  8. Radiological Anatomy

Anatomical Position

  • A person standing upright.
  • Head, eyes, and toes directed anteriorly (forward).
  • Arms adjacent to the sides with the palms facing anteriorly.
  • Lower limbs close together with the feet parallel.

Body Positions

  1. Supine position: Person lies on the back with face directed upwards (Recumbent).
  2. Prone position: Person lies on the abdomen with face directed downwards.
  3. Lithotomy position: Person lies supine with hips and knees semiflexed, thighs abducted and feet strapped in position.
  • Other notes: This position is useful in examination of pelvic organs of female and is commonly practiced for delivery of a baby.

Anatomical Planes (Body Planes)

  • Sagittal Plane
  • Coronal (Frontal) Plane
  • Transverse (Horizontal) Plane

Detailed Planes

  • Midsagittal (Median) Plane:
    • A vertical plane.
    • Divides the body into two equal halves (right & left).
  • Parasagittal Plane:
    • Situated to one or the other side of the median plane and parallel to it.
  • Coronal (Frontal) Plane:
    • A vertical plane.
    • Divides the body into anterior (ventral) and posterior (dorsal) parts.
    • Perpendicular to the midsagittal plane.
  • Horizontal (Transverse) Plane:
    • A horizontal plane.
    • Divides the body into superior and inferior parts.

Quiz (Orientation and Planes)

  • Which letter indicates a Transverse plane? Answer: C (based on the slide).
  • A 28-year-old man with head CT in the coronal plane: Which statement best describes this orientation?
    • A. Divides the body into right and left halves.
    • B. Divides the body into anterior and posterior parts. (Correct)
    • C. Divides the body into superior and inferior parts.
    • D. Runs parallel to the long axis of the body.
  • Clinical quiz: Lying down position with face directed down is called?
    • A Supine
    • B Prone (Correct)
    • C Anatomical position
    • D Lateral semi-prone position

Directional Terms: Standard Anatomical Right/Left Terms

  • Right and Left: standard anatomical sides.
  • Distal / Proximal
  • Superior / Inferior
  • Medial / Lateral (from midline)
  • Anterior (Ventral) / Posterior (Dorsal)
  • Midline (the line dividing left and right)

Anterior, Posterior, Superior, Inferior (Directional Terms)

1) Anterior (ventral): Towards the front aspect of the body.
2) Posterior (dorsal): Towards the back of the body.
3) Superior (cranial): A part that is above another or towards the head.
4) Inferior (caudal): A part that is below another or towards the feet.

Medial, Lateral, Intermediate, Proximal, Distal

5) Medial: Towards the midline or inner side.
6) Lateral: Away from the midline or inner side.
7) Intermediate: Between more medial or more lateral structures.
8) Proximal: Nearer to the trunk or point of origin.
9) Distal: Away from the trunk or point of origin.

Ipsilateral and Contralateral

10) Ipsilateral: Two structures on the same side of the body.
11) Contralateral: Two structures on opposite sides of the body.

Superficial and Deep

  • Superficial (external): Towards the surface of the body.
  • Deep (internal): Toward the interior relative to the surface of the body.

Dorsal vs Palmar vs Planter Surfaces

  • Dorsal surface: Posterior surface of hands/feet.
  • Palmar surface: Anterior (ventral) surface of the palm/hand.
  • Planter surface: Anterior (ventral) surface of the sole.

Anatomical Terms Related to Movements

  • Terms include: Flexion, Extension, Lateral Flexion, Abduction, Adduction, Medial Rotation, Lateral Rotation, Circumduction, Elevation, Depression, Protrusion, Retraction, Protraction, Dorsiflexion, Plantar Flexion, Inversion, Eversion, Pronation, Supination, Opposition, Reposition.
  • Movement directions can be shown in a simple schematic: Flexion, Extension, Abduction, Adduction, Medial Rotation, Lateral Rotation, Circumduction, etc.

Specific Movements: Definitions and Examples

1) Flexion: Decreases the angle between two body parts (e.g., elbow or knee joints).
2) Extension: Increases the angle between two body parts (opposite of flexion).
3) Lateral Flexion: Bending movement of a body part in the lateral direction (sideways).
4) Abduction: Movement of a limb away from the midline (e.g., raise arm away from trunk).
5) Adduction: Movement of a limb toward the midline (e.g., bring arm toward trunk).
6) Medial Rotation: Anterior surface faces medially (e.g., medial rotation of arm at shoulder).
7) Lateral Rotation: Anterior surface faces laterally.
8) Circumduction: Circular movement combining flexion, abduction, extension, and adduction (occurs at shoulder joint).
9) Elevation: Raising a body part toward the cephalic end (e.g., shoulder shrug).
10) Depression: Lowering a body part toward the caudal direction.
11) Protrusion: Forward movement of a body part (e.g., protrusion of mandible).
12) Retraction: Backward movement from protrusion (e.g., retraction of scapula at scapulocostal joint).
13) Protraction: Forward movement of a part (e.g., protraction of scapula).
14) Dorsiflexion: Extension at the ankle so the foot points more superiorly.
15) Plantar Flexion: Flexion at the ankle so the foot points more inferiorly.
16) Inversion: Sole of the foot faces medially.
17) Eversion: Sole of the foot faces laterally.
18) Pronation: Medial rotation of forearm so the palm faces backward.
19) Supination: Lateral rotation of forearm so the palm faces forward.
20) Opposition: Touching the thumb to the little finger.
21) Reposition: Returning thumb and little finger away from each other.

Proximal and Distal Movements (Additional Notes)

  • Proximal vs Distal are used to describe relative positions of limbs with respect to the trunk or origin point.

Body Cavities

  • Cavities are open spaces enclosed in the body that house organs.
  • Cavities named according to their position:
    • Dorsal cavity: subdivided into Cranial cavity and Vertebral (spinal) cavity.
    • Ventral cavity: subdivided into Thoracic cavity, Abdominal cavity, Pelvic cavity (collectively the Abdominopelvic cavity).
  • The Thoracic cavity includes:
    • Superior mediastinum
    • Pleural cavities
    • Pericardial cavity within the mediastinum
  • The Vertebral cavity is part of the dorsal cavity.
  • The Ablomino-pelvic region includes the Abdominal cavity and Pelvic cavity.

Summary of Planes and Cavities (Quick Reference)

  • Planes: Sagittal (midline splits right/left), Coronal (front/back), Transverse (top/bottom).
  • Body cavities: Dorsal (cranial, vertebral) and Ventral (thoracic, abdominal, pelvic).

Quick Review Quiz (From Slides)

  • Lying down position with face directed down: Prone.
  • Coronal plane orientation: Divides body into anterior and posterior portions.
  • Transverse plane orientation: Divides body into superior and inferior portions.
  • Orbital/axial orientation, etc.: Not covered here.

References

  • Gray's Anatomy for Students, 3rd edition (Reference cited on slide 34).
  • Clinical Anatomy by Regions, Richard S. Snell, 9th International edition (Reference cited on slide 34).

End of Notes