GROSS ANATOMY
SPINAL CORD
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Spinal cord (in adults ends at the lower border of L. 1
|
|
|
Spinal cord (in children) ends at S. 3
|
|
|
Dura mater ends at S. 2
|
|
|
Arachnoid mater ends at S. 2
|
|
|
Filum terminale ends at coccyx
|
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.
Detailed explanation-2: -Why does the spinal cord of a newborn usually end at the level of L3? After the third month of development, the caudal vertebrae grow faster than the spinal cord.
Detailed explanation-3: -D) True. The spinal cord acts as a relay system between the body and the brain. Efferent (motor) signals from the brain travel down the spinal cord to the correct tissues and afferent (sensory) signals travel from the peripheries, up the spinal cord, and to the brain where they can be interpreted.
Detailed explanation-4: -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.