Diagnóstico y Tratamiento de Trastornos Articulares Sacroilíacos

Bengt Sturesson, MD

El Dr. Bengt Sturesson, que es un experto cuyo trabajo sobre los movimientos de la articulación sacroilíaca ha sido publicado, realiza una presentación sobre el diagnóstico y el tratamiento de articulaciones sacroilíacas durante un evento de SI-BONE en la reunión de la NASS en 2011.

La presentación del Dr. Sturesson incluye lo siguiente:

  • Fundamentos del movimiento de la articulación sacroilíaca
  • Biomecánica de las articulaciones sacroilíacas
  • Pruebas de diagnóstico (prueba de ensayo P4/Ostgaard, prueba de ligamento largo, prueba de elevación de la pierna recta activa)

Divulgaciones: El Dr. Sturesson realiza investigaciones clínicas para SI-BONE Inc.

El iFuse Implant System está previsto para la fusión sacroilíaca en afecciones como la disfunción de la articulación sacroilíaca, que es resultado directo de la desalineación de la articulación sacroilíaca y de la sacroileítis degenerativa. Se incluyen afecciones cuyos síntomas comenzaron durante el embarazo o en el periodo periparto y han persistido después del parto durante más de 6 meses. Existen riesgos potenciales asociados con el iFuse Implant System. Es posible que no sea adecuado para todos los pacientes y es posible que no todos los pacientes se beneficien. Para obtener información sobre los riesgos, visite: www.es.si-bone.com/riesgos

"I want to thank you very much for the opportunity for me to come here and talk to you.  I think that we have evidence now to discriminate sacroiliac pain from common low back pain.  That is my belief.  When I started the research of the sacroiliac joint, it looked like this.  The sacroiliac joint was like a white spot.  The knowledge was really, really low.  But today, we have some specific evidence-based tests, and the treatment can be offered on knowledge-based technologies based on scientifically proven theories.

Well, my name is Bengt Sturesson, and I am working at the hospital in Angelholm, the south part of Sweden.  I started my research in Malmo Hospital that is even more south at the Lund University, and I am very happy to have two colleagues from the Lund University who worked there when I started in Malmo.  But yes, to tell you that Lund and Malmo is 23 meters in-between but we have never very seldom corporations and is still the same situation more or less.  However, I have also the opportunity to work together with Joran Selevic, the inventor of RSA, radiostereometry, and that was very important for me.  With this radiostereometry, you can measure small movements with a curiosity around 0.2 mm and 0.2 degrees.  

Our first question was really to tell are there any movements at all in the sacroiliac joint because that was the big debate in the 80s.  Some people said no, no movements at all, some people said that the joint doesn't exist, and so on.  However, and then it was like this, like Galileo, he was standing in front of the Pope and telling him that the earth was flat; however, said __________ said it is moving.  And it was the same thing what we could say about the sacroiliac joint.  The joint moves.  However, it started for me in 1985, I came to the University Hospital in Malmo, and I was asked what do you want to do in your research?  And I said sacroiliac joint, and everybody shakes their head, and they said why?  Why do you thought this?  Well, I was interested.  I was extremely curious about the area below L5.  So I started to do a lot of literature research and so on.  Of course, it was not easy, but there it was written, but I had all the patients.  

So my colleagues, they were happy.  So all patients with pain below L5, they were directed to me.  So it started to be a long row of mainly women, and I started to do some different things with them.  And of course, we know that we need to have a proper diagnosis.  If we don't have the proper diagnosis, we can't make the proper treatment.  And what I found a lot of different reliability studies and there was a lot about movement, movement tests, position tests, and so on at that time.  But we know today that the hands-on test has very poor reliability, so don't do that.  

Well, I'll continue to movements because the case was movements, and RSA, the radiostereometric analysis, it looks like this.  You need to do double-exposures and then you have to define the sacrum as a fixed segment and the ilea is moving around the sacrum.  The set up looks like this.  You have two focus, you have the patient, and then you have two films.  And then you have to put ___________ both into the patient and into the calibration cage, and from that you come up with really good advanced mathematics to transform this to the films to the 3D system.  And that takes an engineer and doctor to make this project into __________.  I, to be honest, I don't understand the mathematics, and very few orthopedic surgeons need to understand that as well because it's enough that the inventor understood it, and it's really good, and it's used today in hundreds and hundreds of articles in Europe.

The first thing what you start to do is to check the movements, and at that time, the standing hip flexion test was a very important test decided by Kirkalay-Willis who was really promoting this test.  And I was also, I tried to examine the patient.  I wasn't so good, and I decided you're not enough good to examine the patient.  That was the case.  So we did this examination with standing and standing with the left and the right hip maximal flexion.  At the same time, we made a reliability study, and we were not so happy with that because the reliability was extremely bad with the standing hip flexion test.  And then we had the results.  What we found that we had almost no movement at all when doing this test.  The movement was yes close to the error of the method, so we could actually say we can't use it.  

And then we go into the biomechanics of the sacroiliac joints, and I found out from, I met Andrew Flemming, and he looked at the form and force closure, and then you can look at the joint like the second __________ like a form.  If you have a form, it is hard to say, rectangular like this, then you have no movement at all.  The sacrum will stay there.  It's called a form closure, and the form of the sacroiliac joint, it looks like this on the picture.  It is very irregular.  It is a really fixed form, and it is reducing the movement very much.  The second thing is it's a force closure, and it's the muscle force that keeps the sacrum close in-between the ilea, and if you have a very strong force, you can really keep the sacrum in __________.  But this is the reality.  The reality is it's a mix of the form and the force closure.  

So actually with this method, we proved the theory of the form and force closure because if you stand on one leg, you double the load on one leg.  You have to increase the muscle force to balance.  If not, if you don't increase the double force, you will fall onto the floor.  So actually, there can't be proven any movement when standing on one leg.  So actually we say this is an illusion.  If you see movement when standing on one leg, it's an illusion.  What you see is that the pelvis is rotating around the hip mainly, and you can really provoke that.  And the muscle force really compresses the sacroiliac joint.  So that was our first understanding that the standing hip flexion test cannot be used in movement analysis.

We studied, of course, movement in a lot of different ways as well, and we studied with a group of 25 patients in the beginning, and we measured supine to standing.  And between supine to standing, there is a movement around 1.3 degrees in the sacroiliac joint.  If you compare between supine and sitting, the movement is increased 25 percent, but it's up to 1.5 degrees.  It's really small movement, and you can compare 1 degree with 1 mm in the sacroiliac joints.  If you provoke hyperextension, then you can increase the movement.  And there you can come close to 4 mm between the position standing to prone with hyperextension.  We didn't measure prone because standing in prone has been proven before that it's the same position, so it's just to reduce the amount of radiation to the patients.

So what we could find is that the movements are small but they show a constant and almost normal distributed pattern like everything else in the body.  The axis of the rotation, can you see the cross to the X on this picture?  It is the axis of the rotation, and the movement is a sliding motion along the joint.  I didn't prove that.  It was proven previously by Selevic in the study together with Egun.  Position tests and movements tests, it was nothing, but pain provocation tests, it can be recommended.  We know that.  And there was a very good review about pain provocation tests two years ago by Szudek and co-authors.  

And which test do I use in the clinic because I have a test protocol?  My first test is the P4 or Ostgaard test.  It is close to the thigh thrust test, but it's not that extensive.  It is actually you put a gentle force with the hand on the knee in extra force, and you balance the pelvis with the other hand.  You don't put the hand below with a high thrust.  It's too much for this patient because they're usually very sensitized, and if you force too much on them, they can't walk afterwards.

The second test that is evidence-based, it's a long ligament test.  These patients, they are extremely tender just below the posterior or superior iliac spine, and this is also an evidence-based test.  The third test I use, it's called the Menell 2 test, and this was a test where I could show the biggest movement I told you previously.  And you can put the joint into an N position, and you have to be very careful to think about the hip movements first of all because if you have a hip problem, you can't use this test.  But if you have no hip problem, you can use it well, and you have to balance the sacrum with your hand because if you don't do that, you will also test the lumbar spine.  But it's an easy test to do when you have a patient.  

And the last test I use is the active straight-leg-raise test also well documented.  The patient with pain in the sacroiliac region, they can't lift the leg or they can hardly lift the leg.  And then you can compress the joint, and they usually can lift it.  It is like a miracle, so that's good.  This test, many people use it.  It is the Patrick's Faber test.  I don't use it and the main reason, I think it's a too complicated test because there is a lot of things included, but there are tests that say they are SI tests, but I have my doubts.  But this is my personal feeling.  The Gaenslen's test.  It's a good test.  It's also, we did some studies as well on the reciprocal straddle position, and it's really so that you can provoke the movements backwards or forwards with the Gaenslen's test.  But it's a little more complicated to do.  It takes a longer time, and if you have the patience.  I usually don't do it, but sometimes I do it, and this is quite a good test.

Does give this enough evidence for treatment?  And I say yes for future therapy.  That's okay to use this test, and you can say that most likely this is a sacroiliac problem.  However, there are not so many physical therapy treatments to give the patients, and if we look at the literature, the recommendation here is individually tailored physical exercise program and cognitive behavior treatment.  It is the only one that is well recommended, and this can't be given in so many places actually.

What other options do we have?  Manipulation and mobilization, no evidence of that.  Acupuncture, no evidence of that.  Water gymnastics, no evidence.  Physical exercise, low evidence with individual tailored program, and the radiofrequency denervation, we don't have it in Sweden or very few places, but the effect, it goes over.  This slide means for surgery.  It's not enough with this diagnostic test.  We need to confirm the diagnosis.  It is very important.

My protocol is I do the block one or two occasions, and it's very important that this block is done right.  This are the slides I have received from the company, but this is the way I do it.  The inferior part of the joint is the only place where you can find the joint.  I started to do this in the 80s and because at that time they said it is impossible, but it was possible, and you need to use a dye to confirm that you are in the joint.  And also, you have to have a thin needle so when you are in the joint, the needle is not straight anymore.  It is bowed, and that I learned from __________.  I asked him why do you have such a bow in the needle?  It's so thin he said, and that is a good thing. 

The alternative is the CT, to use the CT is also very good, but it's more complicated, then you need the help of the radiologist.  We heard very good about the innervation from __________.  It's a very complicated innervation, and it gives you a lot of problems, of course, because the innervation is so complicated from L4 to S2, and you have to be aware of that when you do your diagnostic procedures.  So I think if you have a very clearcut good block, then it's okay.  If not, redo the injection or do as I do, consider a test fixation.  

When I started this research, I had to do something before I was allowed to do the sacroiliac fusions, so what we did, we fixed the patient with an external fixator.  We measured them before the fixation with this technique of RSA and with after the fixation.  And what did we find?  Well, we find this patient.  The day after the fixator, we usually tighten the fixator as much as needed, and then the patient feels oh, now I have less pain or no pain, and they were happy.  And then they go home and wait at home for three weeks before the surgery.  How can it work?  It works like this.  This is the figure and to the right you can see the iliac wing, and it's where you put the screws.  With very little force, it's irritant Fo, then you can balance the counterforce with the ligaments Fl and together then you compress the joint.  You really reduce the movement in the joint, here you can use the what I told you the force closure.  And the combination of the force closure and the form closure, it will reduce the movement.

So what happens when you put the frame on?  The movement is reduced to less than half of the previous preop movement, and what happens is the sacrum rotates forward, and it came into a more stable position.  And this is the proof of force closure.  

Then we started to do some functional testing as well.  That is the last year, so we checked the patient walking, leg transfer test, stairs, and active straight-leg-raise test.  So that instead of talking about instability because at that time, the discussion was of instable joints, we talk about stability, and the case is you need to have a stable joint.  So we actually made a definition.  After a lot of discussions, we came into this definition.  The effective accommodation of the joints to each specific load demand through an adequately tailored joint compression, as a function of gravity, coordinated muscle and ligament forces, to produce effective joint reaction forces under changing conditions.  And this is the healthy neutral.  They have a stable situation.  Here we have the patients, those with the non-optimal joint stability.  After that, we could start to do the treatment for the protocols.  And here I will show one patient.  You will see her x-rays and she had the tests were positive.  You could see her inability to walk and so on, and I operated on her first on the right side and then on the left side two months later.  And well, the patient is happy and I am happy.  

Thank you."