Anatomical Orientation and Body Cavities

Anatomical Terms

  • Anatomical Position: Body erect, feet slightly apart, palms forward, thumbs away from the body.
  • Directional Terms: Describe the location of one body structure in relation to another.

Regional Terms

  • Axial: Head, neck, and trunk.
  • Appendicular: Limbs (arms and legs).
  • Regional terms designate specific areas within body divisions

Body Planes and Sections

  • Body Planes: Surfaces for anatomical study.
    • Sagittal: Divides body into right and left parts.
      • Midsagittal: Cut perfectly on the midline.
      • Parasagittal: Cut off-center.
    • Frontal (Coronal): Divides body into anterior and posterior parts.
    • Transverse (Horizontal): Divides body into superior and inferior parts.
    • Oblique: Cuts at an angle other than 90° to the vertical plane
  • Sections: Cuts made along a body plane.

Body Cavities

  • Internal cavities provide protection to organs.
    • Dorsal Body Cavity
      • Cranial Cavity: Encases the brain.
      • Vertebral Cavity: Encases the spinal cord.
    • Ventral Body Cavity
      • Thoracic Cavity
        • Pleural Cavities: Each surrounds a lung.
        • Mediastinum: Contains the pericardial cavity and other thoracic organs.
        • Pericardial Cavity: Encloses the heart.
      • Abdominopelvic Cavity
        • Abdominal Cavity: Contains stomach, intestines, spleen, and liver.
        • Pelvic Cavity: Contains urinary bladder, reproductive organs, and rectum.

Membranes in Ventral Body Cavity

  • Serosa (Serous Membrane): Thin, double-layered membranes.
    • Parietal Serosa: Lines internal body cavity walls.
    • Visceral Serosa: Covers internal organs.
  • Named for specific cavity and organs
    • Pericardium: Heart
    • Pleurae: Lungs
    • Peritoneum: Abdominopelvic cavity

Abdominopelvic Quadrants and Regions

  • Quadrants: RUQ, LUQ, RLQ, LLQ (used primarily by medical personnel).
  • Regions: Right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right iliac (inguinal), hypogastric, left iliac (inguinal) (used primarily by anatomists).

Other Body Cavities

  • Exposed to environment
    • Oral and digestive cavities
    • Nasal cavity
    • Orbital cavities
    • Middle ear cavities
  • Not exposed to environment
    • Synovial cavities: joint cavities