nucleus pulposus herniation

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nucleus pulposus herniation

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maoudoody
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01/22/08 - 11:20 PM

your patient has a herniated nucleus pulposus of the intervertebral disc between L4 and L5 vertebrae.which is the most likely condition that your patient would present with?

1-altered sensation in L3 dermatome
2-weakness of muscles innervated by L5 spinal cord segment
3-inability to contract the bladder
4-fecal incontinence
5-weakness in the ability to extend the leg at the knee

papio
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01/23/08 - 03:04 AM

5

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maoudoody
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01/23/08 - 08:29 PM

why 5?

kukaus
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01/24/08 - 05:23 PM

well it's L5. L4-L5 herniation affects corresponding spinal nerve and one below it, here it's L5. why not bladder or colon, well they are sacral plexus innervated. knee extension - femoral nerve, L2-L4

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maoudoody
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01/24/08 - 11:00 PM

what i understand is that the intervertebral foramen between l4 and l5 passes the spinal nerve of the above vertebra which is l4 and this role applies for lumbar and thoracic vertebrae while the opposite in case of cervical vertebrae

so what is supposed to be compressed is l4 why l5 is with it?

Misrati
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01/29/08 - 12:01 PM

sorry I'm in hurry its L5 which injured nod

, I'll be back ...

new_n_lost
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01/29/08 - 02:27 PM

In this question the most easiest way of solving this is by process of exclusion if one doesnt know the fact that they are trying to ask here.

Choice A = Dermatome of L3 is wrong for obvious reasons
Choice B = weakness of muscles innervated by L5 spinal cord segment is the correct answer.
Choice C = inability to contract the bladder is a PANS effect from S2-S4 segment while the internal sphincter is under the control of sympathetic nerves arising from T10- L2. An inability in sphincter control would most likely be a central extrusion rather than a more common lateral extrusion.
Choice 4 = fecal incontinence is again done by Pudendal nerve S2-S4
Choice 5 = weakness in the ability to extend the leg at the knee which is an L2-L4 function should be preserved.

In a L4-L5 disc herniation the L4 nerve is usually spared as it comes out above the L4/L5 space and the disc in between L4and L5 when protruded compress the nerve going infront of it.

There is a very specific test called the Lasegue's sign or the straight leg raise test/sign which is very very specific for L4/L5 disc protrusions. The idea is to stretch the sciatic nerve so if it elicits pain then there is a L4/L5 disc prolapse. While the femoral nerve stretch is done for a higher lumbar lesion. The most common disc herniation is L4/L5 and the most common nerve involved is Sciatic nerve.

Straight Leg Raise Test
Reverse Straight Leg Raise Test

Again my comments and opinion. Lets Discuss.

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epc924
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02/10/08 - 01:25 AM

i think the answer is 5

because spinal between C1 to C7 goes above the corresponding vertebrate and C8 spinal and below exit below the corresponding vertebrate. Thus, in this case, the spinal nerve between compressed between L4 and L5 is L4 spinal nerve. just my 2 cents

new_n_lost
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02/10/08 - 02:43 AM

epc924 wrote:
i think the answer is 5

because spinal between C1 to C7 goes above the corresponding vertebrate and C8 spinal and below exit below the corresponding vertebrate. Thus, in this case, the spinal nerve between compressed between L4 and L5 is L4 spinal nerve. just my 2 cents

your reference please.
Thanks

The general rule is that when an IV disc protrudes, it may compress the nerve roots numbered one inferior to the disc; for example, L5 nerve is compressed by an L4/L5 IV
disc herniation and $1 nerve by a L5/$1 IV disc herniation. Recall that the IV disc forms the inferior half of the anterior border of the IV foramen and that the superior half is formed by the bone of the body of the superior vertebra (Fig. 4.12). The spinal nerve roots descend to the IV foramen from which the spinal nerve formed by their
merging will exit. The nerve that exits a given IV foramen passes through the superior bony half of the foramen and thus lies above and is not affected by a herniating disc at
that level. However, the nerve roots passing to the IV foramen immediately and further below pass directly across that area of herniation.

From Keith L Moore Clinical Anatomy.

Attached Files:
Fig 4.12 From KLM.JPG (204 KB, 25 downloads)

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angel23
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02/10/08 - 07:55 AM

#10

correct me if i m wrong nnl....
for cervical herniations we take the involvemnt of nerve corresponding to upper segment.......eg.in C1-C2 herniation C1 is involved
and in thoracic and lower down we take nerve corresponding to lower vertebrae
like in this case b/w L4-L5.......L5 is involved

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angel23
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02/10/08 - 07:56 AM

#11

i dnt remember where hav i read this....but this concept is in my mind....
plz tell if i m wrong

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new_n_lost
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02/10/08 - 09:12 AM

#12

The first cervical nerve emerges between the skull and the atlas, and cervical nerves C2 to 7 continue to leave the vertebral canal above the correspondingly numbered vertebrae. C8 emerges between the C7 and T1 vertebrae, and the remaining spinal nerves leave below the correspondingly numbered vertebrae.

Yes and this is a diagram which explained me and hopefully everyone else how this works. When we say that nerve pass above the vertebra like C6 will pass superiorly to 6th Cervical Vertebrae and T1 will pass immediately below to T1 vertebrae. Right

But when you take a disc herniation the situation changes. When we talk about L4/L5 herniation agreed the L4 nerve is leaving below the L4 vertebrae but it has left the canal and nerve which has yet to exit the canal shall be impinged upon.

So even though the nerve is leaving the space is L4 but the disc is going to press on L5 as it has yet to leave, similiarly incases of Cervical Disc herniation. If the herniation is between C6/C7 then C7 is affected. Take the lower nerve number in cases of disc prolapes.

Again Moi 2 bits of copper. grin

Attached Files:
HNP.JPG (184 KB, 27 downloads)

Edited by new_n_lost on 02/10/08 - 09:20 AM

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angel23
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02/10/08 - 10:21 AM

#13

okok now i got tht.....
thanks nnl.....ur concepts are mindblowing....!!
this summarises whenever there is disk prolapse u hav to take lower spinal nerve root...!!

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maoudoody
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02/11/08 - 08:38 AM

#14

thnx NNL u r an angel

dr.aki
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02/15/08 - 05:46 PM

#15

I'll pick 2-weakness of muscles innervated by L5 spinal cord segment. The spinal cord segment below the IV disc herniation is usually affected.

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