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.
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.
- 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.
- Optic fixation is constant.
- Begins sagittal plane stabilization.
- Can begin feeling with arms.
- Able to lift the head.
- 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.
- Active grasp across the midline occurs, which leads to turning from supine to sidelying.
- Radial grasp.
- Radial grasp
- Chest breathing combined with abdominal/diaphragmatic activation.
- Turn from supine to prone.
- Can oblique sit onto forearm.
- Pincer grasp.
- High oblique sit.
- Unsupported sitting.
- Side walking.
- Independent steps between surfaces.
- 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
- 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.
There are general compensatory patterns that are evident in almost all the DNS tests, so watch for the following:
- Excessive scapular winging, retraction, elevation.
- Poor diaphragmatic breathing & lateral expansion.
- Excessive lordosis or extensor tone.
- Rib flares.
- Diastasis or rectus abdominis hyperactivity.
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?
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 Turning 2
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.
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
TRX sit to ½ kneel
We also learned a great way to cue squats to increase pelvic floor activation, which I describe in the video below.
We also had some off-topic discussion with quadruped foot versus tripod/short foot, which I outline in the below video.
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.