NERVOUS SYSTEM SPECIAL SENSE
SPINALCORD
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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C1 and C2
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L1 and L2
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T1 and T2
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None of the above
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Detailed explanation-1: -In adults, the cord terminates at the level of L1-L2. Thus the cord spans within 20 bony vertebrae. In a child, it terminates at the upper border of L3. Each of these segments innervates a dermatome.
Detailed explanation-2: -The spinal cord ends around the L1 or L2 vertebrae in adults, forming the conus medullaris. The horsetail shaped area, which extends past the conus medullaris, is called the cauda equina.
Detailed explanation-3: -It is these spinal nerve roots that compose the cauda equina beyond L1/L2. The fact that the spinal cord ends at L1/L2 is very useful in clinical practice in that it allows for spinal taps to be performed to sample CSF without the risk of puncturing the spinal cord.
Detailed explanation-4: -The conus medullaris is the terminal end of the spinal cord, which typically occurs at the L1 vertebral level in the average adult.
Detailed explanation-5: -The spinal cord ends at the intervertebral disc between the first and second lumbar vertebrae as a tapered structure called the conus medullaris, consisting of sacral spinal cord segments.