Posterior Abdominal Wall Notes PDF

Posterior abdominal wall  Components o Lumbar vertebra & IVD o Wing of ilium o 12th rib o Psoas major/ minor o Iliacus m. o Quadratus lumborum m. o Transversus abdomini...

Posterior abdominal wall  Components o Lumbar vertebra & IVD o Wing of ilium o 12th rib o Psoas major/ minor o Iliacus m. o Quadratus lumborum m. o Transversus abdominis m. (posterior part) o Lumbar part of diaphragm  Muscles o Name Origin Insertion Nerve Action Psoas TVP all lumbar -Enter under Ventral Hip flexion major vertebra, sides inguinal lig. rami L1-L3 (thigh if open, of bodies & IVD -lesser trunk if fixed) of T12-L5 trochanter Psoas Sides of bodies & Iliopubic Ventral Weak trunk minor IVD of T12-L1 eminence rami L2-L3 flexor (anterior to major) Iliacus Iliac fossa Lateral to psoas Femoral n. Hip flexion major tendon on (thigh if open, lesser trunk if fixed) trochanter Quadratus Iliolumbar lig., Inferior border Ventral -12th rib: lumborum posterior iliac 12th rib, TVP of rami T12- depresses & crest L1-L4 L3 (or L4) fixes -trunk: ipsilateral lateral flexion -lumbar vertebral column: bilateral extension (maybe)  Diaphragm o Parts  Sternal  Smallest  Origin  Posterior xiphoid process  Costal  Origin  Internal lower 6 ribs & their costal cartilages   Lumbar  Origin  Medial  L crus  Shorter  Vertebral bodies of L1-L2 (maybe L3) & their IVD's  R crus  Vertebral bodies of L1-L3 (maybe L4) & their IVD's  Medial borders of crura  Connected via median arcuate lig.  Lateral  Medial & lateral arcuate ligs.  Medial arcuate lig.  Covers anterior surface of psoas major  Extends from body of L2 -> tip of L1 TVP  Lateral arcuate lig.  Covers anterior surface of quadratus lumborum  Extends from tip of L1 TVP -> 12th rib o Makeup  Peripheral = muscular  Central = tendinous o Dome  R sits higher due to R lobe of liver during expiration  R reaches upper 5th rib (or 4th ICS)  L reaches lower 5th rib o Openings  Aortic hiatus  Posterior to diaphragm  Boundaries  T12 body  L & R crura  Median arcuate lig.  Transmits  Aorta  Thoracic duct  Esophageal hiatus  Anterior & superior to aortic hiatus (level of T10)  Transmits  Esophagus  A & P vagal trunks  Esophageal branches of L gastric vessels  Caval opening  Anterior, superior, R of esophageal hiatus (level of T8)  Within central tendon  Transmits  IVC   Branches of R phrenic n. o Other structures that pierce  Greater, lesser, least splanchnic nn.  Pierce crura  Sympathetic trunk  Passes posterior to medial arcuate lig.  Sternocostal triangle (hiatus)  Gap b/w sternal & costal origins of diaphragm  Transmits  Superior epigastric vessels  Azygos v.  Pierces R crus or through aortic hiatus  Hemiazygos v.  Pierces L crus  Hiatal hernia o Protrusion of part of stomach into mediastinum through esophageal hiatus o Types  Paraesophageal  LC  Peritoneum containing part of fundus of stomach extends through esophageal hiatus anterior to esophagus  Sliding  MC  Abdominal part of esophagus, cardia & part of fundus of stomach slide superior through esophageal hiatus  Congenital diaphragmatic hernia o Failure of 1 or both pleuroperitoneal membranes to close the pericardioperitoneal canals o Intestines occupy space for lungs o 1:2000 newborns  Lumbar plexus o Ventral rami  L1, L2, L3, part of L4  Other part of L4 joins L5 to form sacral plexus  L1  Iliohypogastric & ilioinguinal nn.  L2  Genitofemoral n.  Anterior division  L2, L3, L4  Obturator n.  Posterior division  L2, L3  Lateral femoral cutaneous n.  L2, L3, L4  Femoral n. o Lateral to psoas major  Iliohypogastric n.   Motor  Supplies anterior ab wall, pyramidalis  Sensory  Lateral branch  Posterolateral gluteal region  Anterior branch  Above superficial inguinal ring  Ilioinguinal n.  Sensory  Upper medial thigh  Males  Skin of root of penis & scrotum  Females  Mons pubis & labium majus  Lateral femoral cutaneous n.  Anterior & lateral thigh to knee  Femoral n.  Sensory  Anterior thigh & medial surface of leg  Motor  Iliacus, pectineus, anterior thigh compartment muscles o Medial to psoas major  Obturator n.  Sensory  Medial thigh  Motor  Obturator externus, pectineus, medial thigh compartment muscles o Anterior to psoas major  Genitofemoral n.  Sensory  Genital branch  Anterior scrotum  Mons pubis & labium majus  Femoral branch  Upper anterior thigh  Motor  Cremaster muscles  Common Sympathetic trunk (lumbar part) o 3-5 interconnected ganglia o Location  Passes posterior to medial arcuate lig.  Along medial border of psoas major  Passes posterior to common iliac vessels o Branches  Receives  White communicating rami from upper 2 lumbar spinal nn.  Preganglionic fibers   Gives off  Gray communicated rami to all lumbar spinal nn.  Postganglionic fibers o Aortic plexus  Receives fibers from  Greater, lesser, least splanchnic nn.  Lumbar splanchnic nn.  Vagus nn.  Prevertebral ganglia (celiac, aortico-renal, superior/ inferior mesenteric) o Superior hypogastric plexus  Inferior continuation of aortic plexus  Kidneys o T12-L3, R sits lower because of R lobe of liver o Parts  A & P surfaces  S & I poles  M & L borders o Hilum  Renal v., a., pelvis  Lymph vessels & autonomic nn. o Anterior relations  R kidney  Liver, 2nd part of duodenum, R colic flexure  L kidney  Spleen, stomach, pancreas, L colic flexure o Posterior relations  R kidney  Psoas major, quadratus lumborum, transversus abdominis, diaphragm, 12th rib  subcostal, iliohypogastric, ilioinguinal nn.  L kidney  Same as above & 11th rib o Superior relations  Suprarenal gland o Renal sinus  Renal pelvis exits through here, through hilum, continuous w/ ureter  Renal a. & v.  Major & minor calyces  Lymph vessels  Autonomic nn.  Adipose tissue  Ureter o Descends on psoas major m., anterior to where common iliac a. bifurcates, lateral wall of pelvis, anterior to internal iliac a., to level of ischial spine o Kidney stone locations  Where renal pelvis joints ureter  At pelvic brim   Where ureter pierces bladder  Suprarenal glands o L gland = pyramidal shape  Anterior relation  Pancreas  Stomach & lesser sac  Posterior relation  Diaphragm o R gland = crescent shape  Anterior relation  R lobe of liver  IVC  Posterior relation  Diaphragm o Cortex  Mesoderm o Medulla  Ectoderm (neural crest cells)  Innervated by preganglionic fibers o Arteries  Superior suprarenal aa. (branches of inferior phrenic a.)  Middle suprarenal a. (branch of abdominal aorta)  Inferior suprarenal a. (branch of renal a.)  Common iliac a. o Terminal branch of abdominal aorta o Starts at L4, ends at L5/S1  External iliac a. o Continuation of common iliac a. o Branches  Inferior epigastric a.  Deep circumflex iliac a.  IVC o Union of common iliac vv. at L5 o Pierces central tendon of diaphragm o Visceral tributaries  L & R renal vv.  R suprarenal v. (L drains into L renal v.)  R ovarian / testicular vv. (L drains into L renal v.)  Hepatic vv. o Parietal tributaries  Inferior phrenic vv.  4 pairs of lumbar vv.  Median sacral v.  Lymph drainage o Pre-aortic nodes  Stomach, small intestine, colon, spleen, pancreas, gallbladder, liver  Forms intestinal trunk o Para-aortic nodes   Abdominal wall, kidneys, suprarenal glands, testes/ovaries  Forms lumbar trunks o R & L lumbar trunks + intestinal trunk = thoracic duct