Posterior Abdominal Wall Flashcards
What structures form the posterior abdominal wall?
The posterior abdominal wall is formed by the lumbar vertebrae, muscles, and fascia posterior to the peritoneal cavity.
Describe the boundaries of the posterior abdominal wall.
The boundaries of the posterior abdominal wall include the lumbar vertebrae posteriorly, the lower ribs and iliac crest laterally, and the diaphragm superiorly.
What are the muscles of the posterior abdominal wall?
The muscles of the posterior abdominal wall include the psoas major, quadratus lumborum, iliacus, transversus abdominis, diaphragm, and psoas minor.
Describe the attachments and actions of the psoas major muscle.
The psoas major muscle originates from the transverse processes of the lumbar vertebrae and inserts onto the lesser trochanter of the femur, contributing to hip flexion and external rotation.
What is the innervation of the psoas major muscle?
The psoas major muscle is innervated by branches of the lumbar plexus, primarily the anterior rami of L1-L3 spinal nerves.
Describe the attachments and actions of the quadratus lumborum muscle.
The quadratus lumborum muscle originates from the iliac crest and inserts onto the transverse processes of the lumbar vertebrae and the 12th rib, contributing to lateral flexion and stabilization of the spine.
What is the innervation of the quadratus lumborum muscle?
The quadratus lumborum muscle is innervated by branches of the lumbar plexus, primarily the anterior rami of T12-L4 spinal nerves.
Describe the attachments and actions of the iliacus muscle.
The iliacus muscle originates from the iliac fossa and inserts onto the lesser trochanter of the femur, contributing to hip flexion.
What is the innervation of the iliacus muscle?
The iliacus muscle is innervated by branches of the femoral nerve, specifically the posterior division of the L2-L4 spinal nerves.
Describe the attachments and actions of the transversus abdominis muscle.
The transversus abdominis muscle originates from the lower ribs, iliac crest, and thoracolumbar fascia and inserts onto the linea alba and pubic crest, contributing to abdominal compression and stabilization.
What is the innervation of the transversus abdominis muscle?
The transversus abdominis muscle is innervated by the lower intercostal nerves and the subcostal nerve, branches of the thoracoabdominal nerves.
Describe the attachments and actions of the diaphragm muscle.
The diaphragm muscle originates from the xiphoid process, lower ribs, and lumbar vertebrae and inserts onto the central tendon, contributing to respiration and separating the thoracic and abdominal cavities.
What is the innervation of the diaphragm muscle?
The diaphragm muscle is innervated by the phrenic nerve, primarily arising from the C3-C5 spinal nerves.
Describe the attachments and actions of the psoas minor muscle.
The psoas minor muscle originates from the bodies of the T12 and L1 vertebrae and inserts onto the pectineal line of the pubis, contributing to hip flexion and stabilization.
What is the innervation of the psoas minor muscle?
The psoas minor muscle is innervated by branches of the lumbar plexus, primarily the anterior rami of L1 spinal nerve.
