Intervertebral Disk of Third Lumbar Vertebra (L3–L4) (Discus intervertebralis L3–L4)
Educational content only — not medical advice.
Anatomy
The intervertebral disk of the third lumbar vertebra (L3–L4) occupies the center of the mobile lumbar lordosis. Bearing high rotational and shear forces, its outer lamellae of type I collagen fibers anchor deeply into the vertebral endplates via Sharpey fibers, enclosing the hydrophilic proteoglycan-rich nucleus pulposus.
Clinical notes
Herniation of the L3–L4 disk compromises the L4 nerve root, causing weakness of ankle dorsiflexion (tibialis anterior), diminished patellar reflex, and sensory loss over the medial leg and foot.
Related structures
Educational references
FAQ
What is the role of the Intervertebral Disk of Third Lumbar Vertebra (L3–L4)?
The intervertebral disk of the third lumbar vertebra (L3–L4) occupies the center of the mobile lumbar lordosis. Bearing high rotational and shear forces, its outer lamellae of type I collagen fibers anchor deeply into the vertebral endplates via Sharpey fibers, enclosing the hydrophilic proteoglycan-rich nucleus pulposus.
Why is the Intervertebral Disk of Third Lumbar Vertebra (L3–L4) clinically important?
Herniation of the L3–L4 disk compromises the L4 nerve root, causing weakness of ankle dorsiflexion (tibialis anterior), diminished patellar reflex, and sensory loss over the medial leg and foot.
Source & license
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