Passive prone technique notes

These notes are not meant for manual med specialists with weak hearts. If that fits your constitutional makeup, please, kindly back off NOW.

Anyone who’s learned PPTs with us, this is for you and anyone else brave enough to breathe with their eyes open.

Since some of us so very much love a good debate, let’s play!

Point of argument:

A working model for pelvic articulation must satisfy these working criteria:
1. It has to account for the walking action of the legs
2. It has to account for how the vertebral spine moves to complement the biomechanics of walking.
3. It has to act as a precursor for the lumbar spine to side-bend and rotate in non-neutral (both forward and backward bending)
4. It has to act as precursor for thoracic spine rotation with lumbar neutral and forward bending.
5. It has to block thoracic backward bending.
6. The pelvis should not dislocate when completing the first four items.

Since, as one of my buds says, “talk is cheap, and nothing slides like bullshit,”
Let's try an experiment. Proof, man, show us some cold friggin proof!

Test “A” for rotation.
1. Ask a colleague to sit sideways on the plinth, with buttocks even, and feet planted firmly flat on the floor.
2. Weight should be equally balanced at both buttocks.
3. Stay behind your colleague and place your hands around the pelvis, to block or completely immobilize it.
4. This isolates lumbar rotation as a motion without contribution from the pelvis.
5. Now, if muscles are the singular cause of lumbar rotation. The L3 joint can still rotate.
a. Ask your colleague to rotate their lumbar region slowly in either direction.
b. Be very careful not to force the rotation to the point of engaging the pelvis and leverage.
c. keep the pelvis immobile.
d. The result of this test is that the lumbar spine blocks after a mere few degrees of rotation.
e. Now we know that the L3 joint can’t rotate far with the pelvis immobilized

Test “B” for side-bending.
1. As with previous experiment, we block the pelvis.
2. This time, we engage the lumbar spine in side bending to either side.
3. We likewise find that side bending is restricted to mere few degrees.





Test “C” for combined side bending and rotation
1. blocking the pelvis, ask your colleague side-bend their lumbar spine as best they can toward one side and then attempt to rotate to the opposite side
2. Now, if Freyette’s laws are correct, This combination movement should account for real-world lumbar rotation in neutral / forward bending (these are Bayliss-adapted conventions; In other words, side-bending to one side with rotation to the other side should occur nicely with the spine in AP neutral).
3. We however find that the amount of rotation possible remains minimal at the lumbar vertebrae.

Test “D” for combined rotation and side-bending
1) The same experiments as previous can be repeated, blocking the pelvis and this time starting with
a) lumbar rotation
b) followed by side bending to the same side.
2) This, according to Fryette’s laws of traditonal spinal mechanics, Is how the lumbar vertebrae in work in non-neutral / extension. (Translation: with the spine engaged extended, rotation and side-bending should occur nicely to the same side)
Conventions used here:
1) By extension, we mean that the lumbar spine is in either neutral or forward bending.
2) Again, lumbar extension is here meant to signify lumbar spine being either neutral or forward bent.

Reason for conventions:
When a bone is brought towards bone by contraction of the muscle between those bones, that’s “flexion,” isn’t it? Now, where are the muscles that contract when the lumbar spine bends backward? So isn’t that “flexion?”
For simplicity, then, let’s stick to “forward-bending” and “backward-bending.” It’s just so much clearer.
Discussion:
1) trying out the same experiment in neutral or forward-bending for combined rotation and Side-bending to the same side, we find that rotation is not improved.
2) These simple tests shows that isolated combinations of
a) Local side-bending and rotation and of
b) Local rotation and side bending for the lumbar spine do not and can’t account for the observed real-world amount of lumbar rotation.
I have included the convention of “local” to signify isolation of biomechanics to the segments tested, with no contribution from the SIJ. This is in keeping with the premise of Fryette’s mechanics in the pure form they are presented in textbooks.

Test E.
Adding pelvic side bending:
1) With your colleague in the same position as previous, prop a one-inch thick block or book under the right ischial tuberosity.
i) This side-bends the sacrum to the left. Have a look.
ii) The lumbar spine becomes side-bent to the left as well. Note that the sacrolumbar spine acts biomechanically as one unit here.
2) Now, ask your colleague to rotate to the right, making sure to block all pelvic side-shift to the left. (Side-bent left, rotated right).
3) Note that, in comparison to the previous experiments, Your colleague will be able to rotate further to the right for the lumbar area tested.
4) With the pelvis merely held in horizontal, We observe that the circumferential range of rotation does not equal what we notice in the real world , Insofar as lumbar rotation goes

Pelvic criteria:

Test “F.”
Add a side shift left, still in lumbar flexion, with the patient is same position as in previous, with a block under the right buttocks. (Side-bent left, rotated right, ischial tuberosity elevation Right, pelvic translation left)
Observe that the lumbar spine automatically rotates to the right without any muscular leverage within the sufficient range reflective of what we notice usually happens. This is a range of motion traditionally ascribed as a local lumbar capability phenomenon. We have taken for granted that Fryette mechanics are a local vertebral phenomenon.

Observe the thoracic spine.

Thoracic Experiment one:
1) Repeat the above test. With your colleague sitting up straight, notice that the thoracic spine refuses to rotate right.
2) It is important not to force it to rotate.
a) The thoracic spine is designed to restrict rotation in thoracic (extension) backward bending.
b) This automatic blocking mechanism does occur for forward bending and neutral.
Thoracic Experiment two:
1) In same position as above, side shift the pelvis to the right (rather than the left, as done previously.)
2) This causes the pelvis automatically rotate right, and almost automatically level out on the horizontal plane.
a) Observe how the thoracic spine automatically rotates to the right, together with the pelvis and lumbar spine.
b) On top of this collective rotation of the thoracic vertebrae, there is also an independent movement of the thoracic vertebra into rotation right and side-bending left.
c) Notice how this collection of movements in combination sufficiently mimics the ranges of segmental motion we regularly observe.

These tests basically tell us that the pelvis provides the angle plus side-shift that enables lumbar and thoracic vertebrae movements we take for granted.

We may extend our studies to walking thus:

Setting aside the role of muscles, isolating for bony articulation, we note that walking involves several forces. The main forces involved are:
1. Weight-bearing and leaning.
2. Leg lifting and direction.
3. The changing angles of the Ilia and hip joint.
4. The reciprocal action of the sacroiliac joints.
5. Lumbar vertebral accomodation for this action.
6. the action or contribution of side shift

These notes were based on the highly esteemed and much recommended work of JR Bayliss, D.O.
This intro appears in abbreviated form in the Mini Manual for Manual Medicine by
S. Strix Toledo www.manualmedsolutions.org www.manualmed.blogspot.com