Case 18 Lumbar canal stenosis

Figure 18.1: MRI sagittal T2.

• Q1: What’s the embryological origin of the nucleus pulposus?
• The embryological origin of the nucleus pulposus is the primitive notochord.

• Q2: What’s the type of collagen in the nucleus pulposus and annulus fibrosus?
• The annulus fibrosus contains collagen type 1, while the nucleus pulposus contains collagen types 2 and 3.

• Q3: Describe the motor affection of the L5 nerve root?
• L5 nerve root affection primarily causes weakness in the extensor hallucis longus.

• Q4: provide diagrammatic picture for lumbar back muscles?

Figure 18-2: back muscle.

• Q5: What is sino-vertebral nerve?
• Sino-vertebral nerve is a sensory nerve that innervates the inter vertebral disc, ligament, annulus, and periosteum of spinal canal. It is considered recurrent nerve from the ventral ramus of spinal root reentering the intervertebral foramina to innervate the previous structures.