Diaphragm Anatomy PDF

THE DIAPHRAGM DIAPHRAGM DIAPHRAGM The principle muscle of the respiration Floor of the thoracic cavity, roof of the abdominal cavity A peripehral muscular part and central tendinous part DIAPHRAGM DIaphragm Relations of the diaphragm Superior relations: Pleura & base of the left and right lung Peric...

THE DIAPHRAGM DIAPHRAGM DIAPHRAGM The principle muscle of the respiration Floor of the thoracic cavity, roof of the abdominal cavity A peripehral muscular part and central tendinous part DIAPHRAGM DIaphragm Relations of the diaphragm Superior relations: Pleura & base of the left and right lung Pericardium and diaphragmatic surface of the heart Relations of the diaphragm Inferior relations: On the right; lobes of the liver, right kidney, right suprarenal gland On the left; the left lob of the liver, fundus of the stomach, left kidney, left suprarenal gland and spleen. DIAPHRAGM The muscle fibers of the diaphram arise at certain intervals 1. Sternal part 2. Costal part 3. Posterior vertebral or Lumbar part Sternal part origin; post surface of the xiphoid process insertion; the central tendon Costal part origin; lower 6 ribs and costal cartilages origin; central tendon Posterior vertebral or lumbar portion Posterior vertebral or lumbar portion 1. Right crus 2. Left crus 3. Medial arcuate ligament 4. The lateral arcuate ligament Right crus bodies of lumbar vertebrae 1-3 and from the corresponding intervertebral disc. Fibers diverge and curve upon themselves and from an opening. This opening is called esophageal opening or hiatus. Left crus Arises from the sides of first two lumbar vertebra and from the corresponding intervertebral disc. The medial border of left and right crura are connected by a median arcuate ligament which is located on the anterior surface of the aorta. Medial arcuate ligament It is the thickened upper margin of the fascia covering the anterior surface of the psoas muscle. The medial arcuate ligament extends from the side of the body of the L2 to the tip of the transverse process of the L1. The lateral arcuate ligament It is the thickened upper margin of the fascia covering the anterior surface of quadratus lumborum muscle. Lateral arcuate ligament extends from the tip of the transverse process of the L1 to the lower border of the 12 th rib. ACTIONS OF THE DIAPHRAGM 1. Muscle of inspiration Pulls the central tendon down increases the vertical diameter. 2. Weight lifting muscle Taking a deep breath and fixing the diaphragm to rise the intra abdominal pressure and that will help to support the vertebral column and prevent flexion during lifting heavy objects 3. Muscle of abdominal straining Aid the contraction of anterior abdominal wall muscles and rises the intra-abdominal pressure to evacuate the pelvic content. 4. Thoraco-abdominal pump The descent of the diaphragm decreases the intra-thoracic pressure and at the same time increases the intra-abdominal pressure. This change compresses the blood in the IVC which forces upwards. Openings of the Diaphragm 1. Aortic Opening: (T12) Aorta, Thoracic duct Azygos vein 2. Esophageal Opening: (T10) Esophagus, Left & Right Vagus nerve Esophageal Branch of Left Gasrtic vessels Lymphatics from lower 1/3 of esophaus 3. Caval Opening: (T8) IVC, Terminal branch of Right Phrenic nerve Additional Greater Splanchnic nerve Lesser Splanchnic nerve Lowest Splanchnic nerve pierce the crura Sympathetic trunk passes posterior to the medial arcuate ligament Superior epigastric vessels between the sternal and costal portions of the diaphragm Left phrenic nerve pierces the left dome Weak points of the diaphragm 1. Lumbocostal trigone 2. Sternalcostal trigone 3. Esophageal opening 4. Aortic opening 5. Caval opening Arterial suppy of the diaphragm -Superior phrenic Artery (branch of descending aorta). -Inferior phrenic Artery (branch of the abdominal aorta) -Pericardiacophrenic Artery (branch of the internal thoracic artery). -Musculophrenic Artery (branch of the internal thoracic artery) Innervation of the diaphragm Motor innervation -Phrenic nerves (C 3,4,5 ) Sensory innervation -Peripheral part - intercostal nerves (T5-T11) -Central part - phrenic nreve (C3,4,5) Diaphragmatic Hernias Diaphragmatic Hernias Bochdalek’s Hernia-posterior Morgagni Hernia-anterior Diaphragmatic Hernias