left lower quadrant

Examples of left lower quadrant in the following topics:

• Abdominopelvic Regions

  • The abdominopelvic region can be divided into four quadrants.
  • The left upper quadrant is the location of the left portion of the liver, part of the stomach, the pancreas, left kidney, spleen, portions of the transverse and descending colon, and parts of the small intestine.
  • In the right lower quadrant sits the cecum, appendix, part of the small intestines, the right half of the female reproductive system, and the right ureter.
  • The left lower quadrant houses the majority of the small intestine, some of the large intestine, the left half of the female reproductive system, and the left ureter.
  • The left lumbar region consists of the descending colon, the left kidney, and part of the spleen.

• Periodontal Disease

  • Periodontitis involves progressive loss of the alveolar bone around the teeth, and if left untreated, can lead to the loosening and subsequent loss of teeth .
  • If left undisturbed, microbic plaque calcifies to form calculus, which is commonly called tartar.
  • This section from a panoramic x-ray film depicts the teeth of the lower left quadrant, exhibiting generalized severe bone loss of 30–80%.

• Anatomy of the Liver

  • It is located in the right upper quadrant of the abdominal cavity, resting just below the diaphragm.
  • Traditionally, the liver is divided into four lobes: left, right, caudate, and quadrate.

• Appendicitis

  • Later, as the appendix becomes more inflamed and irritates the adjoining abdominal wall, it tends to localize over several hours into the right lower quadrant, except in children under three years.
  • Also, there is severe pain on sudden release of deep pressure in the lower abdomen (rebound tenderness).
  • In case of a retrocecal appendix (appendix localized behind the cecum), however, even deep pressure in the right lower quadrant may fail to elicit tenderness (silent appendix), the reason being that the cecum, distended with gas, protects the inflamed appendix from the pressure.
  • Also, fecal stasis and arrest may play a role, as demonstrated by a significantly lower number of bowel movements per week in patients with acute appendicitis compared with healthy controls.

• Lobes, Fissures, and Lobules

  • There are three lobes in the right lung and two in the left lung.
  • The lower lobe is the bottom lobe of the right lung.
  • The human left lung is smaller and narrower that the right lung, and is divided into two lobes, an upper and a lower, by the oblique fissure.
  • The lower lobe of the left lung contains superior, anterior, posterior, medial, and lateral bronchopulmonary segments.
  • The right lung has three lobes and the left lung has two.

• Spleen

  • The spleen is located in the left upper quadrant of the abdomen.

• Arch of the Aorta

  • The arch of the aorta runs at first upward, backward, and to the left in front of the trachea; it is then directed backward on the left side of the trachea and finally passes downward on the left side of the body of the fourth thoracic vertebra.
  • At the lower border, this vertebra becomes continuous with the descending aorta.
  • Three vessels come out of the aortic arch: the brachiocephalic artery, the left common carotid artery, and the left subclavian artery.
  • In approximately 20% of individuals, the left common carotid artery arises from the brachiocephalic artery rather than the aortic arch, and in approximately 7% of individuals the left subclavian artery also arises here.

• Thoracic Aorta

  • Contained within the posterior mediastinal cavity, it begins at the lower border of the fourth thoracic vertebra where it is continuous with the aortic arch, and ends in front of the lower border of the twelfth thoracic vertebra at the aortic hiatus in the diaphragm.
  • At its commencement, the thoracic aorta is situated on the left of the vertebral column; it approaches the median line as it descends, and at its termination lies directly in front of the column.
  • The thoracic aorta's relation, from above downward, is as follows: anteriorly with the root of the left lung, the pericardium, the esophagus and the diaphragm; posteriorly with the vertebral column; on the right side with the hemiazygos veins and thoracic duct; and on the left side with the left pleura and lung.
  • The esophagus lies on the right side of the aorta for most of its length, but at the lower part of the thorax is placed in front of the aorta and close to the diaphragm, situated on its left side.
  • The aorta, highlighted in red, includes the thoracic aorta, the section of the aorta which runs from the lower border of the fourth thoracic vertebra to the diaphragm.

• Ischium

  • The ischium forms the lower and posterior portion of the hip bones of the pelvis.
  • The ischium forms the lower and back part of the hip bone .
  • Left hip joint, opened by removing the floor of the acetabulum from within the pelvis.
  • The ischium is labeled at the bottom left of the ilium.

• Brachial Plexus

  • The brachial plexus is formed by the four lower cervical spinal nerves and the first thoracic spinal nerve.
  • These roots merge to form three trunks: The superior or upper (C5–C6), the middle (C7), and the inferior or lower (C8, T1).
  • Each trunk then splits in two, to form six divisions: The anterior divisions of the upper, middle, and lower trunks and the posterior divisions of the upper, middle, and lower trunks.
  • The medial cord is simply a continuation of the anterior division of the lower trunk (C8, T1).
  • The five on the left are considered terminal branches.