4th lumbar vertebra level

This tutorial covers the cross-sectional anatomy at the level of the 4th lumbar vertebra (L4). It begins with an overview of body planes and orientation in cross-sectional images, similar to CT and MRI scans. The tutorial then identifies muscles, organs, nervous structures, arteries, and veins visible at the L4 level. It also discusses the clinical relevance of these structures, particularly in the context of CT colonography for detecting colon cancer. The session concludes with a review of the key anatomical features discussed.

Which plane divides the body into anterior and posterior parts?

• Sagittal plane

• Coronal plane

• Transverse plane

• Oblique plane

What is the main function of the external oblique muscles?

• Rotate the trunk ipsilaterally

• Extend the trunk

• Flex the trunk

• Support the abdominal viscera

Which muscle is a powerful flexor of the hip?

• Psoas major

• Quadratus lumborum

• Rectus abdominis

• Transversus abdominis

What is the role of the multifidus muscles in the lumbar region?

• Flex the trunk

• Support the abdominal viscera

• Rotate the trunk

• Extend the lumbar vertebrae

Which organ is located on the right side of the patient at the L4 level?

• Descending colon

• Ascending colon

• Ileum

• Ureter

What structure is highlighted in green and located within the vertebral canal at L4?

• Abdominal aorta

• Inferior vena cava

• Cauda equina

• Spinal cord

Where does the abdominal aorta typically bifurcate?

• L1 vertebral level

• L4 vertebral level

• L2 vertebral level

• L5 vertebral level

Which vein is located to the anatomical right of the abdominal aorta?

• Portal vein

• Inferior vena cava

• Renal vein

• Superior mesenteric vein

What is the clinical significance of a CT scan at the L4 vertebral level?

• To evaluate spinal cord injuries

• To measure abdominal muscle thickness

• To check for colon cancer

• To assess hip flexor strength

Which artery supplies structures of the midgut at the L4 level?

• Celiac trunk

• Superior mesenteric artery

• Renal artery

• Inferior mesenteric artery