Body Planes, Directions, and Cavities

Body Planes, Directions, and Cavities Because terms such as south and east would be difficult to apply to the human body, other directional terms have been developed These terms are used to describe the relationship of one part of the body to another part The terms relating to body planes, directions, and cavities are used frequently in the study of human anatomy

Planes, Directions and Cavities Body planes Imaginary lines drawn through body at various parts to separate body into sections Directional terms are created by these planes Three main planes Transverse Midsagittal Frontal

Transverse or Horizontal Superior Medial Lateral Inferior Transverse or Horizontal Midsagittal or Median Frontal or Coronal Ventral / Anterior Dorsal / Posterior http://student.brighton.ac.uk/anatomy/body_planes.htm

Transverse Plane Horizontal plane divides the body into top and bottom halves Body parts above other parts are termed superior Body parts below other parts are termed inferior For instance: knee is superior to ankle, but inferior to hip Two other directional terms related to this plane includes Cranial – body parts located near the head Caudal – body parts located near the sacral region of the spinal column (also known as the “tail”)

Midsagittal (or Median) Plane Divides the body into right and left sides Body parts close to the midline, or plane, are called medial Body parts away from the midline are called lateral

Frontal (or Coronal) Plane Divides the body into front and back sections Body parts in front of plane, or on the front of the body are called ventral, or anterior Body parts in back of plane, or on the back of the body are called dorsal, or posterior

Planes, Directions and Cavities Two other directional terms are: Proximal Distal These terms are used to describe the location of the extremities in relation to the main trunk of the body (generally called the point of reference) Body parts close to the point of reference are called proximal Body parts distant from the point of reference are called distal

Body Cavities http://upload.wikimedia.org/wikipedia/commons/6/65/Illu_body_cavities.jpg

Planes, Directions and Cavities Body cavities Spaces within body that contain vital organs Two main body cavities Dorsal or posterior One long, continuous cavity located on back of body Divided into two sections: cranial, which contains the brain, and the spinal cavity, which contains the spinal cord

Planes, Directions and Cavities Body cavities Ventral or anterior Larger than dorsal cavities Separated into two distinct cavities by diaphragm Thoracic cavity is located in chest and contains esophagus, trachea, bronchi, lungs, heart, and large blood vessels Abdominal cavity is divided into upper and lower parts Upper abdominal cavity contains stomach, small intestine, most of large intestine, appendix, liver, gallbladder, pancreas, and spleen Lower abdominal cavity, or pelvic cavity, contains the urinary bladder, reproductive organs, and the last part of the large intestine Three small cavities are orbital, nasal, and buccal, or oral

Abdominal Regions Abdominal regions Abdominal cavity is so large it is divided into regions One method is into quadrants (RUQ, LUQ, RLQ, LLQ) Another method is into regions

Abdominal Regions Center regions Either side of center regions Epigastric (above stomach) Umbilical (near the umbilicus) Hypogastric (below stomach) Either side of center regions Hypochondriac (below ribs) Lumbar (near large bones of spinal column) Iliac, or inguinal (near the groin)

Quadrants versus Regions http://anatomy.med.umich.edu/abdomen/abdo_wall_ans.html