DNS B Course Notes

Whew, I recently finished (and still trying to process) the B level DNS course from the folks at The Prague School. Instructors were Martina Jeszkova and Dr. David Jeurhing. There were a lot of things covered during this 4 day course and I definitely learned a few things. Here are the highlights.

Developmental Principles

The focal point of DNS is the concept of joint centration, a static and dynamic maximal joint surface approximation.  When joint surfaces achieve optimal bony congruency, the muscles surrounding the joint achieve optimal activation and highest mechanical advantage.  The reverse is also true. If muscles coactivate properly, then joint centration occurs.

Conversely, if optimal joint centration is not achieved then muscle imbalances occur. The reverse is also true. This change becomes very problematic, as decentration at one joint effects centration at all the other joints. This may lead to decreased performance at best and at worst increased wear on joint surfaces.

Take lower crossed syndrome (or open scissors if you are a DNS fan) for example. Let’s say we had a problem with our lower back. In order to cope with this trouble, we increase lumbar lordosis and decentrate the lumbar spine. See how it affects the surrounding structures. The pelvis anteriorly tilts, which affects length tension relationships to glutes, hamstrings, and hip flexors. Thoracic kyphosis increases as well, affecting the shoulder girdle and cervical muscles. Basically, play with one body region or joint position and see how it affects the others, and you can develop a decent understanding of joint centration’s implications.

Developmental Milestones

The Newborn

  • No optical contact due to holokinetic movements, which basically means movement due to lack of stability.
  • Mass extensor pattern in supine.
  • Mass flexor pattern in prone.
  • Able to turn head, but cannot lift head off of table.

6-8 weeks

  • Optic fixation is constant.

3 months

  • Begins sagittal plane stabilization.
  • Can begin feeling with arms.
  • Able to lift the head.

4.5 months

  • Able to stabilize in sagittal plane.
  • Functional joint centration of all joints.
  • Rotates head 30 degrees each direction independent of other spinal movement.
  • Grasp as far as midline.
  • Ulnar grasp.

5 months

  • Active grasp across the midline occurs, which leads to turning from supine to sidelying.
  • Radial grasp.

6 months

  • Radial grasp
  • Chest breathing combined with abdominal/diaphragmatic activation.
  • Turn from supine to prone.

7 months

  • Can oblique sit onto forearm.
  • Pincer grasp.

9 month

  • High oblique sit.
  • Crawling.
  • Unsupported sitting.

10 month

  • Side walking.
  • Independent steps between surfaces.

14-16 months

  • True gait

Here are a couple vids of the developmental process.

The Integrating Stabilizing System of the Spine

Much of where joint centration begins at the spinal level, and involves the following functional muscle unit activating in a feed-forward subconscious fashion:

  • Short intersegmental spinal muscles.
  • Deep neck flexors
  • Serratus anterior
  • Diaphragm
  • Abdominal wall
  • Pelvic floor.

Developing proper function of this group is what allows for movement.  However, if one of these muscles becomes dysfunctional, the entire complex becomes dysfunctional. Stability is then achieved by substituting with other muscles groups and/or passive structures.

Stabilizing system function is very important as we develop, as lack of this mechanism may lead to abnormal bone structuring. Examples of this would be anterior pelvic tilt, femoral anteversion, spinal kyphosis, etc. These would be deemed utilizing passive structures to increase stability for function.

There are 3 reasons for which stability becomes disturbed.

  1. Culture, sport, habit.
  2. Abnormal early development.
  3. Protective pattern due to pain or pathology.

DNS tests

There are general compensatory patterns that are evident in almost all the DNS tests, so watch for the following:

These patterns are results of poor punctum fixums, which are fixed points to which muscles pull. For example, with supine cervical flexion the fixed point would be T4. If mobile, you may see excessive movement there, hence poor centration. The tests themselves unfortunately require a lot of subjective interpretation in terms of what you see, so I will not give you a demonstration. Here is a brief description of each.

  • Diaphragm test – seated breathing.
  • IAP pressure test – Supine breathing.
  • Trunk & head flexion test – max flexion of cervical spine in supine.
  • Arm elevation test – Shoulder elevation in supine.
  • Extension test – Prone head lift.
  • Oblique trunk flexion – Somewhat cross between an armbar and get-up.
  • Quadruped rock forward – Watching for winging.
  • Squat – Duh.
  • Low kneeling – See below exercise.
  • Bear position – See below exercise.

Three Level of Motor control

The three levels of motor control are as follows:

1)      Spinal/brain stem – neonatal. Think primitive reflexes that we see in babies such as rooting, moro, etc.

2)      Subcortical – The first year of life.

3)      Cortical – 2-4 years of age.

I will not go into details regarding all the different reflexes; much of these are what you learned in school. This section was one I had some qualms with after recent discussion (i.e. me listening in awe) with Bill Hartman.  I do not know that science agrees with maturation in the first year of life being subcortical and reflexive. In order for movement to occur, motor learning and motivation are required. These two are both cortical phenomena. If there were reflexive changes, then should not all babies develop optimally?

Reflex Locomotion

Then we went over the “voodoo” aspect of DNS—reflex locomotion (RL). What occurs with this technique is evoking partial motor patterns via afferent stimulations (i.e. pressure) at specific points. These specific points correlate to the support zones that occur throughout the developmental cycle. By pressing on these points, joint centration can be established allowing for motion.

Typically these movements occur more readily with younger children and babies, and sensitivity differs amongst adults. Here are some of the changes typically looked for in RL.

  • Breathing patterns
  • Muscle fasciculation
  • Partial/whole movement patterns
  • Autonomic responses

Realize that RL is not a learning/training process and does not teach normal movement. RL achieves muscle activation, stereognosis, and body awareness—prerequisites for movement.

Here are some videos of the positions that I learned in the course from someone who is obviously way better at this modality than I am.

Reflex Turning 1

Reflex Creeping

Reflex Turning 2

1st position

The group at my course was generally very reactive and elicited some movements. Even I had a reaction elicited in reflex turning 2. However, it is important to understand that everyone in the course knew what was to be expected; hence I wonder if there is some “Ouija boarding” occurring when we perform these activities.

We did have a couple kiddos come in for treatment as well who had neurological problems. Some “responses” got elicited, though these were very minor and I could not tell very well if these were responses or if the kids were just fidgety. Now, seeing pre and post gait everyone thought there were improvements. Of course, I try to battle confirmation bias somewhat (but it is so damn hard), I had some of my PT colleagues check out the videos. They could neither see a difference nor could they tell which were the pre and post videos. Moreover, it does not help when much of the testing had subjective interpretation. We have to be mindful seeing changes that may not be there, or else you starting looking like the video below.

Now, is there some efficacy in RL? I don’t know. I haven’t seen enough of it to say either way, nor am I good enough at it to elicit regular responses. There is also the time factor that is required to elicit changes, which I have many other techniques that may be just as effective at faster rates. I think the selling point for me will be if I can see nice changes in people with marked neurological deficits. So if anyone has stories, please comment below.

Active Exercise

To the instructor’s credit, they state that you will use the active exercise way more than RL. This is good because this is where I think the DNS bread and butter lies. The exercises have been an excellent adjunct in my practice. Here are the big principles regarding exercise that DNS advocates.

  • Develop sufficient body awareness by feeling correct and incorrect movement.
  • Quality over quantity
  • Perform movements slow and pay attention to how one is moving.
  • Keep centration throughout.

The exercises utilize correspond with the various developmental positions, so here are some examples that I have been utilizing and playing with.

4.5 month breathing with band pulldown courtesy of my man Bill Hartman with the wonderful Eric Oetter.

3 month prone with head turns

4.5 month reach

6 month supine breathing

7 month low oblique sit with press

Roll to 8 month oblique sit.

Low kneeling plank

Tripod to bear to squat

Bear crawls

TRX sit to ½ kneel

Squat Cues

We also learned a great way to cue squats to increase pelvic floor activation, which I describe in the video below.

Quadruped Foot

We also had some off-topic discussion with quadruped foot versus tripod/short foot, which I outline in the below video.

Final Verdict

Now I realize that there were some DNS concepts that I knocked, however I will say that the exercise portion of things is very good. Our nervous system is looking for novel input, and I feel the exercises are a great way to provide this. We all developed too, so neurologically these positions are somewhat familiar albeit challenging at time. What is more, DNS exercise does an excellent job of integrating all the body segments into moving as one unit as opposed to training/rehabbing specific body segments. I can appreciate that the folks at the Prague School have taken many different concepts and tied them together into one unit.

So should you take their courses? I say yes. I still learned a great deal in both A and B despite my gripes, and I plan on taking C this fall. So check out the Prague school and learn some good skills.

I also would like to shout out my good friend/fellow mentor PT/cameraman/all around good guy Scott Passman for taking some of these videos, as he put in great effort to make them look good.

26 comments

  1. Hi Zac

    I have been following your blog recently and have really appreciated your posts on Explain Pain/Sensitive Nervous System. Your latest on DNS continues in that vein. I have done the A B C series and one of the specialist modules over the last three years and agree that it’s main strength is functional exercise based on the developmental positions/movement.

    A couple of observations on what you have written here. At 6 months breathing should be diaphragmatic if I am not mistaken?

    The second is about RL. I think there are some old studies on Vojta Therapy including a large population one in Japan (I think) on patients with neurological deficit. It was mentioned on one of the DNS courses but I can’t find a reference at the moment. Personally I have used RL on a patient with CP and one with MS and they were subsequently treated by one of the Prague physios. They had no prior knowledge of RL before I treated them. Both responded to the stimulation but in an atypical way which is expected with neurological compromise, especially the CP patient who had not known “normal” development. Both reported/showed changes in gait and there was objective reduction in arm spasticity in the CP patient.

    The drawback is that the treatment needs to be given fairly intensely and regularly in these type of patients which is impossible unless they are on state healthcare or are very well off! As a result I have not been able to continue treatment so can give no long term opinion.

    I hope this adds to the debate a little.

    Thanks again for your work.

  2. Hey Mark,

    Thank you for the kind words and excellent comments.

    Regarding 6 month breathing, you are absolutely right regarding the diaphragm. Chest breathing simultaneously occurs in coordination with the abdominals. I will update my current language so there is no misunderstanding.

    As for RL, my questions for you were did you give any explanation of potential evoked motor patterns and what magnitude were the motor patterns that you did evoke? Even explaining to the patient that they may move may lead to them moving. It is similar to why you don’t say “you may feel numbness in your big toe during this neurodynamic test.”

    I do not doubt that you did in fact evoke some motor patterns, and I feel that the drawbacks you bring up are very much legitimate especially in US therapy. Another potential drawback for RL is the lack of motor learning. The folks at DNS state clearly that the movement patterns are artificial and reflexive. I ask if this can translate into volitional and non-volitional movement? How long do the effects last? Moreover, could you have gotten results faster and added a motor learning component by utlizing PNF or NDT?

    1. Hey Zac

      My understanding of RL is that it used to enhance motor learning by stimulating inherent ‘ideal’ motor patterns. In the DNS context it is not used as a stand alone modality but is useful where these ideal patterns have never been expressed or have been lost due to injury etc. It can help where patients are unable to perform instructed tasks, I am thinking specifically of conscious diaphragmatic breathing which as you know already underpins the DNS concept. It is also used in the early treatment of babies and infants with CP where there is no volitional movement to work with. Vojta Therapy is another ball game.

      Yes I did explain to my patients that they may feel involuntary movement as I was providing a treatment rather than operating a blinded study so of course introduced anticipation. However I did not describe the pattern of movement. In the case of the MS patient the initial responses were large on the first session, with the CP patient it took longer. The Prague PT said this was to be expected as the former had known ‘normal motor function’ where as the latter hadn’t. My CP patient was with me for a good few sessions as I charged her a minimal fee and we achieved a meaningful improvement in the spasticity of the right arm and hand. There was involuntary wrist extension without finger flexing during the RL treatment which I was able to use to further mobilise the joint. These effects however will need continual input to maintain. The Prague PT’s recommend home treatment by members of the family!

      1. Very interesting Mark. I will have to try to get my hands on that study. I like that you were giving them Vojta to be done at home. When you mention continual input, are we talking for the foreseeable future or until the patient can perform desired activities on own?

        Again regarding RL and motor learning. How can there be motor learning in a passive approach? I question the idea of inherent motor patterns during development due to the fact that motivation and motor learning are necessary components to development that are cortical and not subcortical phenomena. They base RL on the subcortex which is inaccurate. Otherwise there needs to be better explanation as to why some babies do not develop normally. If it were reflexive, wouldn’t all babies develop “normally?”

  3. Zac,

    Great job on the post. And many others! I appreciate the work you have done here and look forward to reading more.

    I am curious about how you would compare PRI to DNS. I recall seeing Bill Hartman post some thoughts on FB and I would be interested to hear your take.

    1. Todd,

      Thank you for the kind words.

      Let me preface my PRI/DNS comparisons by saying that I have been exposed to more PRI via Bill than DNS and am heavily biased towards PRI currently. I think my biases are for good reasons. Namely, there are better test-retest methods to PRI than DNS. PRI has much more objectivity than DNS’s subjective interpretations. Plus PRI material is much better organized.

      Moreover, PRI has been working faster than some of the DNS modalities for me at least. But again, I have a rudimentary understanding of both methods and am not proficient in either. I want to give them both the full shot and get better understanding before I make full comparisons. I do not think they are mutually exclusive, and have currently been incorporating both to the best of my abilities. Right now, I base stuff on the PRI tests, use PRI exercise/manual to “reset,” clean up what else is needed via other manual therapy, then hone it in with DNS progressions if I need to. Of course, explaining how pain works is the first line of defense. Reduce threat perception, attain neutrality/centration, mobilize if needed, re-establish appropriate motor behavior, get as strong/powerful/quick as possible. Still have much more to learn.

      1. Hi Zac,

        Thanks for taking the time to respond. I have taken the DNS A course as well as two PRI home courses and find it interesting to contrast and compare them. I agree with some of your points about the subjectivity of the DNS assessments.

        Here’s another question I have about the PRI approach (which applies a little bit to DNS as well.) As you know from reading the pain science from Butler and Moseley, pain often does not correlate well with structural factors such as posture. Plus there are many studies finding no correlation between chronic pain and measurements of posture such as the degree of lordosis, kyphosis, anterior pelvic tilt etc. How do you reconcile this information with the great emphasis placed in PRI (and DNS) about the importance of “position”, posture, alignment, centration, etc.

        1. That is a very good question Todd, and one I proposed to Bill as well. From the PRI perspective, their target is the autonomic nervous system more than anything; using muscles as a sensory stimulus. As we know from Butler’s work, the ANS is often present and can contribute to, but does not cause pain. Therefore, PRI targets ANS neutrality and can have an effect on pain, but does not treat pain.

          When I am under threat, the brain’s top priority is to ensure survival. The largest component of survival is maintaining diaphragmatic function. If I cannot breathe, I cannot survive. The path of least resistance for me to breathe is the pattern that PRI advocates. By breaking that pattern, I can reduce threat perception, influencing the pain experience.

          Unfortunately, you do not hear this from the PRI folks until you do PRI vision. I can understand why. Is it fair to say that most clinicians still subscribe to a peripheral model? If they talked like this at their courses, PRI would be no more because people wouldn’t go. It is easier to understand when described mechanically, though in the home study they clearly state this is neurological phenomena. It is a hard thought to grasp for many that all of what we do in the therapy realm is targeting central processes.

          As for DNS, I feel that the big thing with them is re-establishing motor control. We know motor control is altered during and after a pain experience, so can I make changes in motor control by utilizing some of these positions? Again, to relate to Butler, the developmental positions are a context change in which we move, therefore can be beneficial. I do not know if they truly subscribe to a central model of pain. My guess is doubtful considering that in each DNS course I have been to they have my favorite slide showing a disk herniation gone after 2 years of DNS. They must’ve forgotten that 70% of disks return to a normal state after 1 year of nothing.

          Thoughts?

  4. That reference;

    Immammura,S., Skuma, K, Takahashi, T.: Follow-up study of Children with Cerebral Coordination Disturbance. Brian and Development , 5, 311-4, 1980.

  5. Hi Zac

    Home treatment should be repeated until new motor patterns are embedded. In the case of neurological deficit then this could take some time. I have made the mistake of halting treatment too quickly and got fairly rapid regression. I am afraid I have no time scales on this and it is probably down to individual response.

    On your other point about passive treatment and motor learning, my understanding of RL in the DNS context is that it is used to stimulate inherent motor patters, therefore priming the system for active DNS exercise. It is not used alone and there are no claims for using it solely for motor learning. I think pure Vojta therapy uses it as a stand alone treatment and that is the distinction between the two.

    I have in my notes that 70% of babies develop a normal motor pattern and the remaining 30% probably include those with frank motor disturbance such as CP or sturctural deformity. However I take your query over why those with non pathological disturbance don’t develop normally if it is an inherent pattern. I will have to think further on that one and get back to you. By the way if you have questions of this sort then you can email the Prague PTs and they will get back to you. I have done this a few times myself and always had excellent help.

      1. It seems I haven’t replied direct! Can you give me a way to PM you and also remove my email address from the post below. Thanks.

  6. Hi Zac,

    Thanks for the response. I agree that there are mixed messages from PRI about how they achieve pain relief. In the two home courses I did, the instructors repeatedly stated that bad posture or alignment or position is a cause of pain and that fixing position can treat pain.

    Thanks for explaining the perspective that you got from the vision course with regard to the ANS. That is an interesting explanation and a little similar to the way I sometimes think of the movement work I do with my clients. Even if optimizing movement patterns is not likely to reduce mechanical micro trauma and resulting nociception, perhaps they can change the way the brain interprets the level of threat to the affected areas. A great deal of brain power goes towards making movement efficient, and therefore I think the brain might be quite pleased to discover safer more efficient movement patterns, even if they don’t make a big difference in terms of tissue damage and primary nociception.

    However, your explanation and mine still leaves me with a question. If good movement and good breathing, (e.g. a centrated horizontal diaphragm) reduce threat and pain, then it seems to me that one prediction this hypothesis should make is that people with a more horizontal diaphragm would have less pain. But as I read the literature on posture and pain correlations, that is not what we see. Perhaps I am interpreting it wrong, which is certainly possible!

    As to whether the DNS people incorporate a sophisticated understanding of pain science, I definitely noticed my instructor Petra was very careful about distinguishing nociception from pain in her languaging. So that was a good sign. But there were lots of pictures of herniated discs …

    1. Erson Religioso mentioned to me when I took his eclectic approach course that posture is a risk factor, not a causative factor for pain.

      The problem with correlating movement, breathing, posture, with pain is that pain is an incredibly multifactorial experience. Many of these correlational studies cannot take into account the vast variation in psychosocialemotional factors that contribute to one’s pain experience. Maybe your forward head doesn’t induce nociception that results in pain one day, but maybe on the day that you didn’t sleep well, lose your job, and get run over by a bus it does. I don’t know if we will ever be able to determine why person x gets pain when person y presents in a similar fashion does not. The best we can do is use our skills (education, breathing, movement, manual therapy) to get that person back toward optimal function.

  7. Hi to both of you

    I will reply with my thoughts on abnormal motor development in children soon but just a thought on the last post. Developing the theme of forward head posture (or any other) not being significant on its own but maybe significant when other factors are involved, it is still a useful observation and explanation in context. The patient has consulted you as a PT and has some expectation of your structural/functional diagnosis/hypothesis, if this explanation is given in a non threatening way and you empower the patient with tools to help correct this it still has therapeutic value. You may not be altering peripheral structure, or even intending to but you have changed something in the patient’s CNS that should be of value. Of course you should base your approach on the current best evidence and this should be the main body of your explanation.

    1. I agree with your sentiment at least in terms of functional-type explanations. However, I have gone very much by the wayside in terms of explaining structural pathology. I generally find that a) I am not good enough to determine an exact structure for nociception, nor do I think anyone else is, b) breaking out models freaks people out. Think how many people get the death sentence feel when they become diagnosed with OA or some other structural pathology, and c) people who have had chronic pain for many years have heard every structural diagnosis, and often times does not apply due to increased central sensitivity.

      The research shows that explaining pain neurobiology is more effective than pathoanatomical explanation/backschool/whatever and people can get it. We can’t underestimate people’s ability to understand pain science. It may not be what the patient expects, but it is probably the best way to reduce threat perception. I give some semblance of this to most every patient I see, and I haven’t had anyone walk out on me yet. And if they do walk out on me, then chances are I couldn’t help them in the first place.

  8. I concur with everything you say here, my thoughts were really along the lines of a functional issue that the patient can take control of thereby empowering them. But yes the structural models/explanations are counterproductive, as I found out yesterday after being given a diagnosis of ACL insufficiency/rupture!

  11. Hey Zac. I’ve been perusing your blog for about a year and I’m fully aware that this comment comes about 2.33 years after this blog entry was originally posted. Anyways, I’m a patient who is fascinated with PRI, but has no formal anatomy training. With that said, many of your picture captions confuse me. Case in point, can you please provide some explain the issue presented in the picture that has the Sigourney Weaver caption. That protrusion is the linea alba, correct? I’m assuming that this type of protrusion signifies dysfunction at some level, but my question is why. I know my wife was scared she tore it during her pregnancy and I see this type of protrusion (although not as pronounced) occasionally in my 18 month old. Hell, I can actually create that protrusion when I do a double leg lowering exercise. Any thoughts are appreciated and thanks for your time.
    -Ryan

    1. Glad you read this far back Ryan 🙂

      The captions are meant to be confusing non-sequiturs in most cases…The only relation is usually something small in the preceding paragraph(s).

      The protrusion is a diastasis recti https://en.wikipedia.org/wiki/Diastasis_recti

      The linea alba is stretched for a multitude of reasons, some listed above. If I have an overactive rectus that can create pulling at the linea alba, especially with eccentric contraction (think lower crossed/open scissors with an active rectus abdominis).

      The protrusion you get on the DLLE is likely your rectus carrying too much of the workload…need some IO’s and TA’s.

      Hope this helps,

      Zac

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