lumbar RFA technique tips

[heathermed]

Hello everyone

I have been struggling with lumbar RFAs and was hoping to get a different perspective.
Can anyone please share how you go about doing RFAs and if you have picked up any tips or tricks that may help me become better over the years.

thank you

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[bedrock]

simple, attend a lumbar SIS course.

However, I must ask. Are you a physician? Have you completed a spine or pain fellowship?

 

[heathermed]

yes. currently in a pain fellowship. I have done quite a few so far this year. I was just hoping to get some different perspectives and perhaps some tricks of the trade that come with many years of experience.

 

[lobelsteve]

yes. currently in a pain fellowship. I have done quite a few so far this year. I was just hoping to get some different perspectives and perhaps some tricks of the trade that come with many years of experience.

Come to nass 5.19.16 in Chicago. Weekend course. Great instructors.

 

[willabeast]

this is a vast subject. going over the ISIS (now ISI) RF power point slides over and over again helped me more than anything else.

 

[powermd]

Hello everyone

I have been struggling with lumbar RFAs and was hoping to get a different perspective.
Can anyone please share how you go about doing RFAs and if you have picked up any tips or tricks that may help me become better over the years.

thank you

Some simple advice.

I have tried lots of techniques over the years, and settled on this one.

The overall goal is to get the needles to take trajectories about parallel to the vertebral bodies as they land in the SAP/TP groove. Every patient is slightly different, some much more so than others, so having a technique that is flexible enough to account for this is helpful.

Do L4 and the sacral ala first (anatomical levels here, not MBs). These can be placed in about the same caudo-cranial plane.

1) Square L4 with the beam. This is about perpendicular to the table for most patients. Maybe slight caudad angulation.
2) Place sacral ala needle coaxial with the beam. Place pointer needle next to L4 SAP. Oblique beam to 20-25°. Line up the pointer with a point superior/inferior where you'd like to land on the pedicle. Swing back to AP. Starting position is more superior than you thought it would be, huh? Adjust medial/lateral position of the pointer needle so you have enough room to clear the SAP as you advance into the groove between the SAP and TP. Place the needle in AP, then check oblique. Doesn't that look nice?
3) Repeat with L3, which is usually squared slightly more caudad than L3.
4) Place L5 needle last, since that requires some cranial angulation. You will find that L4 and L5 needles come pretty close for patients with a lot of curvature.

This technique takes a bit more time than just picking a view and slamming the needles in, but you will avoid discovering too late that certain needles are poorly placed.

 

[Extralong]

this is a vast subject. going over the ISIS (now ISI) RF power point slides over and over again helped me more than anything else.

FYI, I think its SIS not ISI. lol

But yea, SIS and ASIPP courses were pretty helpful. Also if you are a res/fellow, the courses are much much cheaper then if you were out in practice.

 

[Pacman27]

Powermd is on point

Go to a course or learn this in your fellowship. Thats the point of the fellowship. If this procedure is not done right, results will suck. That harmful to the patient, you, and the specialty.

The big thing to understand there are alot of variances on the patient anatomy. Especially when dealing with the sacral ala.

I feel strongly about this procedure because its one that work and can work very well, even for morbidly obese patients (to my surprise) . Its all a procedure that will save patients from unnecessary and unneeded surgery

 

[Taus]

Some simple advice.

I have tried lots of techniques over the years, and settled on this one.

The overall goal is to get the needles to take trajectories about parallel to the vertebral bodies as they land in the SAP/TP groove. Every patient is slightly different, some much more so than others, so having a technique that is flexible enough to account for this is helpful.

Do L4 and the sacral ala first (anatomical levels here, not MBs). These can be placed in about the same caudo-cranial plane.

1) Square L4 with the beam. This is about perpendicular to the table for most patients. Maybe slight caudad angulation.
2) Place sacral ala needle coaxial with the beam. Place pointer needle next to L4 SAP. Oblique beam to 20-25°. Line up the pointer with a point superior/inferior where you'd like to land on the pedicle. Swing back to AP. Starting position is more superior than you thought it would be, huh? Adjust medial/lateral position of the pointer needle so you have enough room to clear the SAP as you advance into the groove between the SAP and TP. Place the needle in AP, then check oblique. Doesn't that look nice?
3) Repeat with L3, which is usually squared slightly more caudad than L3.
4) Place L5 needle last, since that requires some cranial angulation. You will find that L4 and L5 needles come pretty close for patients with a lot of curvature.

This technique takes a bit more time than just picking a view and slamming the needles in, but you will avoid discovering too late that certain needles are poorly placed.

No caudal tilting or coming from caudal to cephalad? Unless I misunderstood what you wrote, that would not place tip of electrode parallel to the nerve, rather more perpendicular to the nerve in the junction of sap/tp ?

I essentially use a combination of what's in furmans atlas and SIS, with a bunch of slight variations and nuances that I picked up in fellowship and from colleagues. Goal here is to get longest length of exposed electrode tip possible laying parallel to the nerve high n tight in the sap/tp junction.

An example from a recent case I had saved (due to some odd transitional anatomy)

:

 

[geauxg8rs]

No caudal tilting or coming from caudal to cephalad? Unless I misunderstood what you wrote, that would not place tip of electrode parallel to the nerve, rather more perpendicular to the nerve in the junction of sap/tp ?

I essentially use a combination of what's in furmans atlas and SIS, with a bunch of slight variations and nuances that I picked up in fellowship and from colleagues. Goal here is to get longest length of exposed electrode tip possible laying parallel to the nerve high n tight in the sap/tp junction.

An example from a recent case I had saved (due to some odd transitional anatomy) View attachment 201744:View attachment 201745View attachment 201746

I do a similar technique

 

[powermd]

Looking at the anatomical pictures here:
http://www.asipp.org/reference3/Lau2004PainMed.pdf

I doubt it matters whether your angle is steep caudal or more perpendicular as long as the tip of the needle is in the groove. I'm burning at 90°C x 2 with a 90° rotation medial in between.

I'll try a few your way to see if there is a difference in sensory stimulation.

 

[NJPAIN]

Some simple advice.

I have tried lots of techniques over the years, and settled on this one.

The overall goal is to get the needles to take trajectories about parallel to the vertebral bodies as they land in the SAP/TP groove. Every patient is slightly different, some much more so than others, so having a technique that is flexible enough to account for this is helpful.

Do L4 and the sacral ala first (anatomical levels here, not MBs). These can be placed in about the same caudo-cranial plane.

1) Square L4 with the beam. This is about perpendicular to the table for most patients. Maybe slight caudad angulation.
2) Place sacral ala needle coaxial with the beam. Place pointer needle next to L4 SAP. Oblique beam to 20-25°. Line up the pointer with a point superior/inferior where you'd like to land on the pedicle. Swing back to AP. Starting position is more superior than you thought it would be, huh? Adjust medial/lateral position of the pointer needle so you have enough room to clear the SAP as you advance into the groove between the SAP and TP. Place the needle in AP, then check oblique. Doesn't that look nice?
3) Repeat with L3, which is usually squared slightly more caudad than L3.
4) Place L5 needle last, since that requires some cranial angulation. You will find that L4 and L5 needles come pretty close for patients with a lot of curvature.

This technique takes a bit more time than just picking a view and slamming the needles in, but you will avoid discovering too late that certain needles are poorly placed.

I use a technique that is more SIS like. Line up superior end plate then caudal tilt 20 degrees and ipsilateral oblique 20 degrees at levels above sacral ala, 5 degrees at ala. BUT, intrigued by Powermds technique as it could be a better way if it is more fool-proof. I'm lost in step #2. If you have images I would love to see them or if you have a reference for where it is described that would help.


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[powermd]

I use a technique that is more SIS like. Line up superior end plate then caudal tilt 20 degrees and ipsilateral oblique 20 degrees at levels above sacral ala, 5 degrees at ala. BUT, intrigued by Powermds technique as it could be a better way if it is more fool-proof. I'm lost in step #2. If you have images I would love to see them or if you have a reference for where it is described that would help.


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I'll post a pic tomorrow if I have a lumbar RF.

 

[bedrock]

I doubt it matters whether your angle is steep caudal or more perpendicular as long as the tip of the needle is in the groove.

No difference with initial relief, but you get a longer duration of effect if your cannulae angle is more caudal as you then burn a longer segment of the nerve.

This what I was taught by Dreyfuss in fellowship.

 

[powermd]

I don't have data on all my patients, but the ones who come back for repeats usually do it around 12-15 months.

 

[Papa Lou]

Where's the lumbar RF pictures powermd?
promises promises

 

[powermd]

Where's the lumbar RF pictures powermd?
promises promises

Oddly enough I haven't had a lumbar RF. A bunch of cervicals though.. go figure.

 

[Papa Lou]

Bringing this one back. I've switched to a new technique for me. I was using Furman. Now I'm using SIS. I place the medial branch block needles prior to placing the RFA needles so that at the steep 30-40 degree caudad view I can see the landing spots by following the mbb needle tips. It does get pretty obscured otherwise. In the end the RFA needles do look picture perfect the way Taus images show, BUT they look much better on lateral view. Taus images have very poor lateral view placement, per SIS standards. The active tip should cover the middle of the posterior element mass. I usually have the needle point just about to enter foramen on lateral (motors always tested and negative of course) then I turn 180 and pull back a few millimiters so the active tip covers more ground posteriorly as well. Results long term I don't know yet I just started 1 month ago. Takes a LOT longer this way. Which I don't like. The main reason for this is I realized the MB is often in the very groove or just medial to it along the base of the SAP and my placements before may have been a tiny bit lateral. Nowadays the AP view shows very "high and tight" placement and my initial approach prior to rotating 180 seems more accurate. Certainly it's a more scientific approach to placing the probes.

b/c of the time it takes I'm considering a two needle technique. Less emphasis on the exact trajectories. Just place them more like Furman said 15 degrees oblique and 15 caudad. It's easy to see landmarks that way, the placement is quick and simple. If I place two needles spaced 2-3 mm apart I should get a super duper wide burn and no way I miss the thing. Duration I don't know but I would assume I kill the nerve more often than the silly 180 degree thing.

What techniques are you all using?
Does SIS teach the technique in their book at their $2,500 workshops?
Seems all the mbb needles are a hassle to place and LOTs more radiation.

 

[NJPAIN]

Bringing this one back. I've switched to a new technique for me. I was using Furman. Now I'm using SIS. I place the medial branch block needles prior to placing the RFA needles so that at the steep 30-40 degree caudad view I can see the landing spots by following the mbb needle tips. It does get pretty obscured otherwise. In the end the RFA needles do look picture perfect the way Taus images show, BUT they look much better on lateral view. Taus images have very poor lateral view placement, per SIS standards. The active tip should cover the middle of the posterior element mass. I usually have the needle point just about to enter foramen on lateral (motors always tested and negative of course) then I turn 180 and pull back a few millimiters so the active tip covers more ground posteriorly as well. Results long term I don't know yet I just started 1 month ago. Takes a LOT longer this way. Which I don't like. The main reason for this is I realized the MB is often in the very groove or just medial to it along the base of the SAP and my placements before may have been a tiny bit lateral. Nowadays the AP view shows very "high and tight" placement and my initial approach prior to rotating 180 seems more accurate. Certainly it's a more scientific approach to placing the probes.

b/c of the time it takes I'm considering a two needle technique. Less emphasis on the exact trajectories. Just place them more like Furman said 15 degrees oblique and 15 caudad. It's easy to see landmarks that way, the placement is quick and simple. If I place two needles spaced 2-3 mm apart I should get a super duper wide burn and no way I miss the thing. Duration I don't know but I would assume I kill the nerve more often than the silly 180 degree thing.

What techniques are you all using?
Does SIS teach the technique in their book at their $2,500 workshops?
Seems all the mbb needles are a hassle to place and LOTs more radiation.

I'm interested to know how many others are using a 30-40 degree declined view to place the probe. I am using the guidelines I learned from the Algo's old website and Gofeld's article that recommend squaring the superior endplate and then declining 20 degrees from there. Some, like Milt Landers advocate placing a marker at the SAP-TP junction of the LEVEL BELOW then declining the II until the maker overlaps the target level. Not sure what angle that turns out to be. I have the most difficulty with L5-S1 and the LR DR. In my patients the L5-S1 is often so collapsed that it is difficult for me to square off the superior endplate of the sacrum from the AP view. Therefore, my L5 DR needle is often high up on the S1 SAP.
Regarding using two needles; I would just use 16 ga needles unless you are proposing using 2 - 16 ga needles. I went from 20ga to 18ga a year ago and see better results.
Finally, regarding the time it takes to do the procedure. My OR time and fluoro times are double that of my colleagues in the ASC and that really bothered me. I was told that MacVicar in NZ, who allegedly has THE BEST results on planet earth, takes 60-90 minutes to do a single side 3 level MB RF so perhaps you really cannot do a bilateral 3 level RF in 15-20 minutes. I take a fairly long time, radiate the crap at of myself, and I am still not entirely happy with my results. I am starting to believe that I am just that much more critical of my results and technique than those who blast through the procedure and talk a good line of BS.

 

[Taus]

Great discussion. I use a bit of a hybrid to get the trajectory angle. Tilt to about 15-20 where I can still see junction. I tilt in 5 degree increments to verify I can still see target. I enter skin slightly caudal and lateral to target, then come a little out of coaxial/plane and aim tip to junction. Then I tilt back to square ep. Local on os. Then walk up to high n tight at junction. If this all looks perfect on 30 degree oblique, i.e. Exactly along course of nerve, I'm happy. I use lateral to verify I'm not too deep. I found that when I kept working to get needle deeper towards ventral sap after seeing lateral I invariably came off cephalad off os. If ap and 30 degree oblique look ideal, lateral looks safe, I'm happy. 2nd burn I retract a little, then turn 90-180 and go up wall of Sap. Takes me 20-30 mins for unilateral 3-4 nerves.

For L5... I'm never happy with placement in junction til I really oblique a lot and see sap completely separate medially from lateral aspect of vertebral body. That's helped me a lot.


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[pmrmd]

Personally I'm more anterior than the pictures provided above, especially at the ala.

 

[DOctorJay]

Bringing this one back. I've switched to a new technique for me. I was using Furman. Now I'm using SIS. I place the medial branch block needles prior to placing the RFA needles so that at the steep 30-40 degree caudad view I can see the landing spots by following the mbb needle tips. It does get pretty obscured otherwise. In the end the RFA needles do look picture perfect the way Taus images show, BUT they look much better on lateral view. Taus images have very poor lateral view placement, per SIS standards. The active tip should cover the middle of the posterior element mass. I usually have the needle point just about to enter foramen on lateral (motors always tested and negative of course) then I turn 180 and pull back a few millimiters so the active tip covers more ground posteriorly as well. Results long term I don't know yet I just started 1 month ago. Takes a LOT longer this way. Which I don't like. The main reason for this is I realized the MB is often in the very groove or just medial to it along the base of the SAP and my placements before may have been a tiny bit lateral. Nowadays the AP view shows very "high and tight" placement and my initial approach prior to rotating 180 seems more accurate. Certainly it's a more scientific approach to placing the probes.

b/c of the time it takes I'm considering a two needle technique. Less emphasis on the exact trajectories. Just place them more like Furman said 15 degrees oblique and 15 caudad. It's easy to see landmarks that way, the placement is quick and simple. If I place two needles spaced 2-3 mm apart I should get a super duper wide burn and no way I miss the thing. Duration I don't know but I would assume I kill the nerve more often than the silly 180 degree thing.

What techniques are you all using?
Does SIS teach the technique in their book at their $2,500 workshops?
Seems all the mbb needles are a hassle to place and LOTs more radiation.

SIS has a specific RFA course. I did it in Denver. Great course both lectures and cadaver time. Plenty of needle time at each station.

They don't place the MBB needle first and then caudal tilt but it was mentioned if you have difficulty locating the target.

My technique is similar to Taus but I've really been focusing on the L5 DR since the course. Landers taught a nice technique.

If you want to be faster gotta go with venom, nimbus, or cooled I would think. Your site of service obviously dictates whether or not this is feasible.


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[Aether2000]

16ga needles....85 deg C ......cook for at least 90 sec

 

[Papa Lou]

Not ready to make the leap to 16g yet.
I do like how Taus is doing it now. If I tilt 20-25 I can still make out the sulcus. Then I will cheat by entering skin a little caudad and going a tiny bit out of plane. This is probably about a 30 degree total I agree. Obliqued 15 degrees I'll placed the probes. I do need the laterals to look optimal though so that will require tinkering. Current technique they look monster but it's too many needles and fluoro. I guess I am relieved that some of the more critical guys that chase optimal results are taking a long time as well.

Still the realities of PP means time needs to be balanced as well...20 minutes is a fair goal. Problem is I burn twice 90s and can't get Venom.

Glad to hear how people do these things. These technical discussions are not in writing anywhere and elevate this forum. Too many people want to be individuals and be "the best" and don't share their key tips and tricks.

 

[Papa Lou]

16ga needles....85 deg C ......cook for at least 90 sec

Yes but what angle of approach? Or is your point it does not matter in practice when you bomb the whole area with a 16g cannula?

 

[NJPAIN]

Taus,
To clarify:
1. Do you caudal tilt in 5 degree increments BEYOND 15-20 degrees?
2. What is your oblique angle of approach?
3. You return to a view square with the endplate(s) to advance the cannula high and tight to the SAP

 

[DOctorJay]

I line up the spine in PA and ipsilateral oblique maybe 10 degrees. I use the 18 gauge needle as a marker and put it at the corner of the inferior vertebral body's superior end plate. That is my entry point.

It ends up being very close to where SIS instructs the entry point to be when you ipsi oblique and then caudal tilt. I paid close attention at the course as to where we were entering with the caudal tilt and it was very similar.

My approach means you have to drive the needle without being coaxial. Once I see I'm just at the inferior portion of the TP if I haven't touched bone yet I'll steepen up my angle and dive for bone. If I go past the top of the TP I pull back and readjust til I contact bone. Then I walk it up into position.

Ends up being a very similar technique in terms of where the needle ends up but is faster since you don't do all the c-arm movements.

My final position looks very similar to Taus but I try to be a bit more ventral especially after attending the SIS course. I'm using 18g but am probably switching to 16 soon or doing nimbus.


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[Taus]

Taus,
To clarify:
1. Do you caudal tilt in 5 degree increments BEYOND 15-20 degrees?
2. What is your oblique angle of approach?
3. You return to a view square with the endplate(s) to advance the cannula high and tight to the SAP

1. No, from square EP I do 5 or 10 degree increments of caudal tilt, keeping my eye on junction at each move until 15-20 degrees. The more ancient the spine, the smaller the increments. In the occasional 50yo I'll go right to 20, but my avg rf patient has terrible landmarks.

2. I start at 15 oblique. If I can't clearly see junction I oblique slightly more til I can.

3. Yes. I maintain the oblique and tilt back to square EP, put in some local on os and walk up to ideal target.


DrJ- I see your point about saving time and fluoro by approximating the angle and coming in well out of plane, but w the avg body habitus and needing to withdraw and redirect to properly hit target on os I'd think it could be a wash? Also agreed my example pic above not ideal ventral depth.


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[DOctorJay]

1. No, from square EP I do 5 or 10 degree increments of caudal tilt, keeping my eye on junction at each move until 15-20 degrees. The more ancient the spine, the smaller the increments. In the occasional 50yo I'll go right to 20, but my avg rf patient has terrible landmarks.

2. I start at 15 oblique. If I can't clearly see junction I oblique slightly more til I can.

3. Yes. I maintain the oblique and tilt back to square EP, put in some local on os and walk up to ideal target.

Most of the above tips were learned from colleagues and trouble shooting myself to improve my efficiency and get past sticking points. The small part of starting slightly lateral to target has helped me a lot with regards to getting high/tight/medial enough. In past when setting up exactly at target I'd repeatedly deflect lateral.

DrJ- I see your point about saving time and fluoro by approximating the angle and coming in well out of plane, but w the avg body habitus and needing to withdraw and redirect to properly hit target on os I'd think it could be a wash?


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definitely harder with the larger patients and I will cheat further down than the corner for them

 

[NJPAIN]

As Papa Lou stated, you can’t find these technical aspects written anywhere. These discussions really get me thinking and changing my practice for the better. Even the best atlas leaves out so many details and can be terribly misleading. Because of this, I believe a lot of interventionalists do what they think is a good job but technically really is not. Either that or the effect of this procedure is more placebo than anything else.

Regarding the ventral placement of the cannula on lateral view, look at three different “good” atlases. You will see the cannula tip anywhere from immediately posterior to the foramen to posterior to the junction of IAP and SAP. Who’s correct?

Another thing you will see in nearly every atlas is that all of the cannulae are placed perfectly parallel to one another. The more I try to perfect my technique and individualize every level the more I find that my needles are going off in different directions, almost never parallel and at times the skin entries are very close. Especially in the elderly. I asked Milt Landers about that. His opinion was that your cannulae most often should not be perfectly parallel. He shared with me that he does one level at a time. He doesn’t move on to place a cannula at the next level until all of his burns are completed at the previous level. Obviously that takes a long time but he reports very good outcomes.

Is it possible that in PP the best approach is get one view, throw in some 16 ga cannulae parallel to one another, two or more burns per level and wrap up 3 levels in 10 minutes? Are the perceived results any different? I don’t know.

 

[Papa Lou]

As Papa Lou stated, you can’t find these technical aspects written anywhere. These discussions really get me thinking and changing my practice for the better. Even the best atlas leaves out so many details and can be terribly misleading. Because of this, I believe a lot of interventionalists do what they think is a good job but technically really is not. Either that or the effect of this procedure is more placebo than anything else.

Regarding the ventral placement of the cannula on lateral view, look at three different “good” atlases. You will see the cannula tip anywhere from immediately posterior to the foramen to posterior to the junction of IAP and SAP. Who’s correct?

Another thing you will see in nearly every atlas is that all of the cannulae are placed perfectly parallel to one another. The more I try to perfect my technique and individualize every level the more I find that my needles are going off in different directions, almost never parallel and at times the skin entries are very close. Especially in the elderly. I asked Milt Landers about that. His opinion was that your cannulae most often should not be perfectly parallel. He shared with me that he does one level at a time. He doesn’t move on to place a cannula at the next level until all of his burns are completed at the previous level. Obviously that takes a long time but he reports very good outcomes.

Is it possible that in PP the best approach is get one view, throw in some 16 ga cannulae parallel to one another, two or more burns per level and wrap up 3 levels in 10 minutes? Are the perceived results any different? I don’t know.

Landers seems like he does a studly job at everything from listening to him at the disco course. I agree most interventionalist results probably suck and the variance is killing the field in the eyes of people like 101N. I believe the quoted RFA results of 50-65% improvement is because of that. I agree the needle entries at each level sometimes touch if you square each level and tilt individually. It makes it a pain to fine tune them at that point. I stopped doing that for that reason. My current method does leave them spaced out at skin but also on lateral view and AP view they come in at respectable angles not silly/useless angles. I prefer Taus' current technique over DrJ and it's not significantly more time/fluoro. I'll be switching...(and thankfully getting rid of the mbb needle markers). The one thing that gives me pause is the SIS book explicitly states not grinding bone into perfect placement. That's the benefit of being as close as possible to coaxial b/c less "walking off" needs to be done.

Most importantly I have a question for those of you with the highest yield results: how important is it for you to see the multifidus twitches on motor stim? If you don't get them do you fish the needle around until you do? I have found when I don't initially get it if I fish up medially up the SAP a little I get it. Not sure what it matters to see it or not, but if feeels so good to see it twitch then zap.

 

[NJPAIN]

I will let the others answer regarding multifidus twitch. I had the same concern and asked same question a while back.


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[clubdeac]

I rarely get multifidi twitch at L5 DPR for what it's worth.. maybe I suck?

 

[Ligament]

I rarely get multifidi twitch at L5 DPR for what it's worth.. maybe I suck?

Nope, it is very rare to get multifidi twitch at the PDR. I believe the multifidi is residual at this level or innervated differently. I see it approximately 5% of the time at the PDR. I see it >80% of the time at all other levels including C7 and C8.

 

[NJPAIN]

Nope, it is very rare to get multifidi twitch at the PDR. I believe the multifidi is residual at this level or innervated differently. I see it approximately 5% of the time at the PDR. I see it >80% of the time at all other levels including C7 and C8.

So, your are at the L5 level going after L4 MB. You do not do sensory testing. Radiographically cannula placement looks good. You go up to 2 v at 2 Hz and no twitch. Do you lesion or reposition?


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[Ligament]

So, your are at the L5 level going after L4 MB. You do not do sensory testing. Radiographically cannula placement looks good. You go up to 2 v at 2 Hz and no twitch. Do you lesion or reposition?


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I would be sure I am radiographically well placed and safe. If so, I would lesion. If my cannulae placement does not look great, I would reposition and motor stim again. Some multifidi are very atrophied and don't twitch much. Some multifidi are covered by 8 inches of fat, and we cant see the twitch. Maybe I'll crank it to 3V in that case. And of course, some people will not have a multifidi twitch no matter what. The thing I am doing motor stim for is to rule out placement on nerve root, not necessarily to rule in placement over the medial branch (though that is a nice secondary confirmation, and I like to see it).

 

[bedrock]

Agree that L5 rarely has local motor twitch. You should get some local motor twitch L2-L4 if on target, (unless you inject local just before final cannula advancement)

I would recommend everyone attend an ISIS (SIS) RF course. Good CME and worth the time and money. The course clears up the concerns brought up in this forum and the ISIS RF course is very clear and easy to follow unlike some of the descriptions in the ISIS book.

The last thing I would emphasize is that good RF takes time. Paul Dreyfuss is the MBB/RFA expert of North America. I trained with him, and he performs all his MBB/RF according to the technique at the SIS courses. He was one of the main creators of the RFA and MBB courses via SIS (ISIS).

With MBB or intra-articular facet injections, he is always on target but very fast. However for RFA, even with his expert level of training, Dreyfuss would take 20 min of procedure time(30 min case, 20 min of him actually doing the case), to do a unilateral 3-4 nerve lumbar RFA, and 35-40 min procedure time for a bilateral 4 nerve lumbar RFA.

As you might expect his RFA success rate was very high, >95%, and he often repeated RFA on patients that failed it from local docs , and 80% of the time he would achieve success on those patients, due to his superior technique. In addition to ideal SIS technique he uses 18G RF cannulae and burns for 120 seconds.

My point is that to achieve good RFA results, you need to check all the angles, which takes time. You have to take time to perform good RFA. Physicians doing a unilateral lumbar RFA in only 10 min of actual procedure time are not doing the best RFA that can be done for their patients.

 

[BobBarker]

I just eyeball it out of AP. Here is one I did today. Just start lateral and inferior and work my way home. You can see the venom electrode deployed if you look closely.

 

[NJPAIN]

Either you have the most amazing new Carm or this was a 100lb 35 year old


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[BobBarker]

74yo. At least 140lbs. You can see the air/fat line back there.

I work in an old cath lab from the late 1990s. The " c arm" has lots of hours. I took this pic after it was loaded to our pacs. I also decreased the gain quite a bit. I think that is what makes the details clear, right @freddydpt ? I just have an old crt monitor in the rad room.

 

[Papa Lou]

Bob I would say you're coming in too parallel to the SEP / perpendicular to the MBB tract which doesn't burn long enough along course of nerve. But I admit I know nothing.

When it comes to getting MBB twitches I am very disappointed in my % rate of twitches. Of course L5 dorsal ramus typically doesn't innervate the multifidus often so I rarely get that, but at medial branches above that I get those lovely / satisfying twitches only 50% of the time. And my placement radiographically is something I feel I obsess on. Also I'm going by "feel" when getting into position before confirming nice placement radiographically. I look for the needle to twitch so I see it despite fatty backs. I look for the slightest twinge and half the time don't see it! It's so frustrating. I go to 1.5 V only not beyond that. Is that why? I dunno.

In the cervical I get twitches >90% of the time.

I'll check out the SIS course if anything just to feel good about what I'm already doing and to ask more about these beloved twitches (which are not discussed in the literature or recommendations in any way b/c the purpose of motor testing is to rule out nerve root involvement)

 

[DOctorJay]

Go up to 2V and you'll catch more twitches.


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[Ligament]

This shows ideal L5 PDR placement, parallel to the dorsal of the sacrum. Main point of these images is to show ideal L5 PDR placement.

 

[clubdeac]

Are those 16g?? Whoa so badass

 

[bedrock]

Great pics

Great job on being parallel to sacrum, however L5 is also too ventral, just like the needles above it.

 

[Ligament]

Great pics

Great job on being parallel to sacrum, however L5 is also too ventral, just like the needles above it.

Thank you. I agree with you. I initially posted the wrong lateral image, I put in better initial images as well as second burn images. May still be too ventral for some folks.

 

[cbest]

Nice Lig - thanks for posting! About what angle of caudal tilt were you at for each level?


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[bedrock]

Thank you. I agree with you. I posted the wrong lateral image, put in a better one as well as second burn images. May still be too ventral for some folks.

second lateral looks much better. I'd still withdraw 1-2mm, but that's me.

 

[Ligament]

Nice Lig - thanks for posting! About what angle of caudal tilt were you at for each level?


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My pleasure. I've learned so much on SDN I'm happy to contribute when I can. For L5 PDR, square up L5-S1 disc, then tilt caudally 60-65 degrees. for all other lumbar levels, square up disc space, tilt caudally 30-35 degrees.

 

[Ligament]

Are those 16g?? Whoa so badass

Yes 16ga. Nothing badass, but thanks ;-)