Multifidus twitch at L5 dorsal ramus

[GottaHaveIt]

Hey,

First year attending here.

I do cooled and occasionally thermal RF.

I have been having difficulty obtaining any local motor twitch with my L5 dorsal ramus motor testing. Not sure what I am doing wrong. I can post pictures later... is this a common issue?

In fellowship no one cared about local twitch at all because we did 90% cooled RF, but in residency we obsessed over getting even a faint twitch before starting the lesion.

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[SSdoc33]

L5 is the hardest to get. sometimes i dont get it. burn and move on if you are in a good spot anatomically and there is no motor firing in the leg.

 

[fathead88]

Just move on if the fluoro looks appropriate. You won't always get one.

 

[callmeanesthesia]

Often no/minimal twitch. As long as the leg isn’t twitching I move on.

 

[painfree23]

Hey,

First year attending here.

I do cooled and occasionally thermal RF.

I have been having difficulty obtaining any local motor twitch with my L5 dorsal ramus motor testing. Not sure what I am doing wrong. I can post pictures later... is this a common issue?

In fellowship no one cared about local twitch at all because we did 90% cooled RF, but in residency we obsessed over getting even a faint twitch before starting the lesion.

Can you post ur pic? Make sure ur quite parallel to the nerve. I get it about 25% of the time.

 

[lobelsteve]

Why are you trying to get a motor twitch?
The goal of motor testing is to show you are not stimulating the L5 nerve root.

 

[Ferrismonk]

I don't care about multifidus twitch at all. Put your needle in the same spot your MBB was, test for motor (meaning leg, not back), if negative then burn.

 

[NJPAIN]

I almost never see a twitch at L5 DR.

 

[drrosenrosen]

Agree with Steve. I do motor testing (in contrast to what Bogduk now recommends) just to rule out radicular stim. If I get multifidus twitch, fine, but I don't go chasing it. Even when I did go chasing it in the past, L5 is always hard to get and often "ungettable"

 

[kstarm]

As above, I check for radicular symptoms with motor testing. Often there is no twitch at L5 but patients do note a pain or pressure sensation, though not always.

 

[drusso]

Why are you trying to get a motor twitch?
The goal of motor testing is to show you are not stimulating the L5 nerve root.

You can't get to 60 procedures per day while checking sensory and motor stim.

 

[Taus]

Motor stim is for the lawyers. Fluoro shows you accurate placement. Just do >1 lesion with large gauge rf fully covering target zone with parallel placement to nerve.

 

[lobelsteve]

You can't get to 60 procedures per day while checking sensory and motor stim.

Exactly. And now with no sedation money i just gotta go MIS with sij fusions, minutemen, milds, and a ton of dead baby dust.

Gotta make bank to keep the hookers and cocaine flowing.

 

[fathead88]

I don’t know if you’re kidding or not but it takes 5 seconds to check motor stim. I think we’ve all probably seen a spinal nerve response, look up at the fluoro, say “huh” in our head, and backed the needle up a 1/2 cm.

 

[pastafan]

Like a peripheral nerve block, low voltage equals distance. Motor stim at .2-.5 means first lesion most likely nailed nerve and second lesion is overkill. This has led to excellent duration of relief.

 

[pmrmd]

I’m more intrigued by OPs first sentence—
cooled and occasional thermal RF.

Wut?

 

[Orin]

Relationship between paravertebral muscle twitching and long-term effects of radiofrequency medial branch neurotomy - PMC

To achieve a prolonged therapeutic effect in patients with lumbar facet joint syndrome, radiofrequency medial branch neurotomy (RF-MB) is commonly performed. The purpose of this study was to evaluate the prognostic value of paravertebral muscle ...

www.ncbi.nlm.nih.gov

The data are weak for correlation of better RF with motor capture of the paraspinals, but it does seem to have some face validity. Similar to sensory capture though, it's just not a clear advantage

With that said, I do use motor capture for safety.

 

[TIVAndy]

L5 dorsal ramus - i try one or two adjustments - if i get twitches great, if not i move on if placement looks good. btw, even if you do get it, it can be subtle twitch so forget it in pts who are big

 

[Laryngospasm]

Decreasing response from L2>L5 with often no response at L5. Also realize many of these patients aren’t very high on the muscle mass index. Sometimes you’ll feel a subtle if you palpate.

 

[Ligament]

Why are you trying to get a motor twitch?
The goal of motor testing is to show you are not stimulating the L5 nerve root.

I agree with Steve; local multifidi twitch is not particularly important. Goal is to r/o being too close to the root.

Furthermore, multifidi twitch is VERY rare at the L5 PDR. Perhaps I see it in <5% of patients. It will get more profound as you go from L4, to L3, to L2, etc. Again, its not in itself important. Just something I observe.

 

[painfree23]

L5 dorsal ramus - i try one or two adjustments - if i get twitches great, if not i move on if placement looks good. btw, even if you do get it, it can be subtle twitch so forget it in pts who are big

What do you adjust?

 

[TIVAndy]

What do you adjust?

rotate needle 180, or move 1-2 mm around