Lecture 1 PDF

Level 2 Semester 3 Module Posterior Abdominal Wall Dr. Alaa Badawy Ass Prof of anatomy Dr. Aya Soliman Demonstrator of Anatomy Contact information  Posterior abdominal wall 1) Muscles B. Psoas major C. Psoas minor D. Quadratus lumborum. E....

Level 2 Semester 3 Module Posterior Abdominal Wall Dr. Alaa Badawy Ass Prof of anatomy Dr. Aya Soliman Demonstrator of Anatomy Contact information  Posterior abdominal wall 1) Muscles B. Psoas major C. Psoas minor D. Quadratus lumborum. E. Iliacus. 2) Blood supply F. Aorta G. IVC 3) Nerve supply: Lumbar plexus. 4) Organ Pancreas 20XX presentation title 4  Muscles A. Psoas major B. Psoas minor C. Quadratus lumborum. D. Iliacus 20XX presentation title 5  Psoas Major Origin : Transverse process of all lumbar vertebrae. The adjoining parts of the bodies of (T12- L5) & intervertebral discs in between. Insertion : Lesser trochanter of the femur 6  Psoas Major MS: Nerve supply : L1, L2 & L3 Action 1. Flexion of the thigh 2. flexion of the trunk (bend the trunk forwards) 20XX presentation title 7  Psoas Minor: Origin : From the sides of the bodies of (T12- L1) and the disc in between. Insertion : Iliopubic eminence of the hip bone. 20XX presentation title 8  Psoas Minor: Nerve supply : L1 spinal nerve Action : Weak flexor of the trunk Lateral flexion of the trunk.. Stabilizes the last rib. 20XX presentation title 9  Iliacus: Origin: From the upper 2/3 of iliac fossa. Insertion : With the psoas major into the lesser trochanter of the femur. 20XX presentation title 10  Iliacus: Nerve supply : femoral nerve (L2,3,4). Action Assists the psoas major muscle in flexion of the thigh. 20XX presentation title 11  Quadratus lumborum Origin : Iliac crest Iliolumbar ligament Transverse process of L5 Insertion : The medial half of last rib. Transverse processes of (L1- L4). presentation title 12  Quadratus lumborum Nerve supply : Subcostal nerve (T12). L1, 2, 3 Action : 1. Lateral flexion of the trunk. 2. Stabilizes the last rib 20XX presentation title 13 Relation of the kidney to the posterior abdominal wall muscles 20XX presentation title 15 Lumbar plexus Site: within the substance of psoas major muscle. Formation: Formed by the ventral rami of the upper 3 lumbar nerves & the upper part of the ventral ramus of the 4th lumbar nerve. 20XX presentation title 17  Branches Intersted In Getting Laid On Fridays. Ilio- hypogastric nerve (L1).. Ilioinguinal nerve (L1).. Genitofemoral nerve (L1,2).. Lateral cutaneous nerve of the thigh (L2,3) Posterior Division. Femoral nerve (L2,3,4) Posterior Division.. Obturator nerve (L2,3,4) Anterior Division.. Accessory obturator nerve (L3,4). 20XX presentation title 18  Branches o Muscular: - Psoas minor: L1. - Psoas major: L2, 3, 4. - Quadratus lumborum: L 1, 2, 3 20XX presentation title 19 Relation to Psoas Major: Lateral to Psoas Major: Iliohypogastric nerve. Ilioinguinal nerve. Lateral cutaneous nerve of the thigh. Femoral nerve. Medial to Psoas Major: Obturator nerve. In front of Psoas Major: Genitofemoral nerve. 20XX presentation title 20  The Posterior Abdominal Wall Muscles of the posterior abdominal wall Psoas major Psoas minor Quadratus lumborum Iliacus Origin 1. Transverse process of 1. From the 1. The posterior 5 cm of 1. From the upper all lumbar vertebrae. sides of the the inner lip of the iliac 2/3 of iliac 2. Bodies of (T12-L5) & bodies of crest. fossa. intervertebral discs in (T12- L1) 2. The iliolumbar ligament. between by five and the disc tendinous arches in between. (which bridge over (present in 60% the lumbar vessels). of subjects) Insertion ❖ lesser trochanter of the ❖ Iliopubic 1. The medial half of last ❖ With the psoas femur eminence of rib. major into the (Iliopsoas tendon). the hip 2. The tips of transverse lesser trochanter bone. processes of (L1- L4). of the femur. Nerve ❖ L1, 2 & 3. ❖ L1. ❖ Subcostal nerve (T12). ❖ From the femoral supply ❖ L1, 2, 3. nerve (in the abdomen). Action 1. Flexion and lateral ❖ Weak flexor A. On one side: lateral ❖ Assists the psoas rotation of the thigh. of the trunk flexion pf the trunk. major muscle in B. On both sides: flexion of the 1. Extend the lumbar part thigh. of vertebral column. 2. Acts as a muscle of respiration. If acting from below: 2. On both sides: flexion of the trunk. 3. On one side: lateral flexion of the trunk. Clinical importance of psoas major: ☒ TB infection of the vertebral column may spread through the blood to the vertebrae (hematogenous spread), particularly during childhood. An abscess resulting from tuberculosis in the lumbar region tends to spread from the vertebrae into the psoas sheath, where it produces a psoas abscess. ☒ Pus from the psoas abscess passes inferiorly along the psoas muscle deep to the inguinal ligament to the superior part of the thigh.  Psoas Major & Iliacus muscles All 4 muscles of the posterior Psoas Minor muscle Abdominal wall Lumbar plexus ❖ Location: Inside the psoas major ❖ Formation: Ventral rami of upper 4 lumbar nerves. ❖ Branches: Muscular: Named branches: 1. Psoas minor: L1. 1. Iliohypogastric: L1 2. Psoas major: L2, 3, 4. 2. Ilioinguinal: L1 3. Quadratus lumborum: L 1, 2, 3 3. Genitofemoral: L1, 2 4. Lateral cutaneous nerve of the thigh: L2, 3 5. Femoral nerve: L2, 3, 4 (posterior division) 6. Obturator nerve: L2, 3, 4 (anterior division) 7. Accessory obturator nerve: L2, L3 (anterior division) ❖ Relation of the psoas major to branches of the lumbar plexus: From its anterior surface: Genitofemoral nerve From its lateral border: Iliohypogastric nerve Ilioinguinal nerve Lateral cutaneous nerve of the thigh Femoral nerve From its medial border: Obturator nerve Lumbosacral trunk  Relation of lumbar plexus nerves to psoas major muscle