Body Cavities, Quadrants & Regions PDF

BODY CAVITIES OBA MIKE Body cavities are spaces within the body that help protect, separate, and support internal organs. This separation is done by bones, muscles, ligaments and other structures. The major body cavities include:  Cranial cavity  Ve...

BODY CAVITIES OBA MIKE Body cavities are spaces within the body that help protect, separate, and support internal organs. This separation is done by bones, muscles, ligaments and other structures. The major body cavities include:  Cranial cavity  Vertebral (spinal) canal  Thoracic cavity  Abdominal cavity  Pelvic cavity. There are other minor cavities such as oral cavity, nasal cavities, orbital cavities etc. Cranial cavity The cranial cavity contains the brain. It is formed by cranial bones and has the following boundaries: Anteriorly – frontal bone Posteriorly – occipital bone Superiorly – parietal bones Inferiorly – sphenoid, ethmoid and parts of frontal temporal and occipital bones. Laterally – temporal bones.. Vertebral canal The vertebral canal is also called spinal canal. It contains the spinal cord and beginnings of spinal nerves. It is formed by the vertebral column and has the following boundaries: Superiorly – occipital bone Inferiorly – sacrum Other relations depend on its location. Thoracic cavity Formed by the ribs, intercostal muscles, sternum and thoracic vertebra. It is further divided into: Pleural cavity that contains the lungs Pericardial cavity that contains the heart. Mediastinum that contains all the thoracic organs (viscera) except the lungs. Other contents of the thoracic cavity include; esophagus, trachea, thymus and great vessels. The thoracic cavity ends inferiorly at the diaphragm. It has the following boundaries: Anteriorly – sternum and costal cartilages Posteriorly – thoracic vertebra Superiorly – root of the neck Inferiorly – diaphragm Laterally – ribs and intercostal muscles Abdominal cavity The abdominal cavity extends from the diaphragm and ends as the pelvic cavity. It is formed majorly by abdominal muscles and lumbar vertebrae. The abdominal cavity is the largest cavity. It contains the stomach, spleen, liver, gallbladder, small intestines, and most of the large intestines. Boundaries of the abdominal cavity Anteriorly – muscles of the anterior abdominal wall. Posteriorly – lumbar vertebrae and muscles of the posterior abdominal wall. Laterally – Lower ribs and abdominal wall muscles. Superiorly – diaphragm Inferiorly – continuous with the pelvic cavity. Pelvic cavity The pelvic cavity contains the urinary bladder, parts of large intestines and internal genitals. Boundaries of the pelvic cavity Anteriorly – pubic bones and pubic symphysis Posteriorly – sacrum and coccyx Laterally – Hipbones Superiorly – continuous with the abdominal cavity Inferiorly – Pelvic floor muscles Notes: Organs inside the thoracic abdominal and pelvic cavities are called viscera.  ABDOMINAL REGIONS AND QUADRANTS The area within the abdomen can be divided into nine regions and four quadrants. This division helps anatomists and healthcare workers locate organs easily. It also helps in easy detection of the site of pain, tumor or other abnormalities. Abdominal quadrants The four abdominal quadrants and their contents are: Right upper quadrant (RUQ) o Liver o Gallbladder o Stomach o Duodenum o Pancreas o Right adrenal gland o Right kidney o Ascending colon o Transverse colon Right lower quadrant (RLQ) o Caecum o Appendix o Ileum o Hepatic flexure o Ascending colon o Right ovary o Right oviduct o Right ureter o Right spermatic cord o Uterus (enlarged) o Urinary bladder (full) Left upper quadrant (LUQ) o Liver o Spleen o Stomach o Jejunum o Pancreas o Left kidney o Left adrenal gland o Splenic flexure o Transverse colon o Descending colon Left lower quadrant o Sigmoid colon o Descending colon o Left ovary o Left oviduct o Left ureter o Left spermatic cord o Uterus (enlarged) o Urinary bladder (full) The nine abdominal regions include: 1. Right hypochondrium 2. Epigastrium 3. Left hypochondrium 4. Right lumbar 5. Umbilicus 6. Left lumbar 7. Right inguinal (iliac) 8. Hypogastric 9. Left inguinal (iliac) Assignment List the contents of the regions