The therapeutic value of PKB

[nari]

Thought I would put in a technique that I have had quite a lot of success with:

When testing for reproduction of pain with PKB in prone, I turn the position into therapy when it is positive for low back pain.

If the test is positive at 90 degrees knee flexion or less, I apply pressure at T10-L2 and the knee invariably flexes further; release the pressure and the extra ROM is preserved. It makes for an easy home movement, by crossing the ankles and using that stabilisation , the patient can progress.
If it goes no further, I add hip extension (at home, the patient uses a flat pillow or similar).
It is passive to begin with, then it becomes active.

Cramping of the hamstrings can be a problem; I find a weight (5-6 kgs) over the thoracolumbar spine does the trick in lieu of my hand pressure.

Anyone else find that PKB is a useful tool?


Nari

[emad]

Hi Nari:

I think u have read and take courses in neurodynamics .

BUt , what i know ;

The PKB is a test for femoral nerve tension ,so if u applied that test the pain will be in the front aspect of thigh .

If you reached the level of pain through knee flexion, you will apply perssure , that is ok , why r u going increase the flexion more , this may detiorate the case .

cheers
emad

[nari]

emad -

Certainly, if it does not reproduce pain in the lumbar spine, it will create tension in the front of the thigh. That may or may not be useful to know.
I use it as a treatment only if it reproduces the lumbar pain the patient is complaining of.

It does not make the pain worse - it will relieve it. We are not talking long stretching - I never do that- but 3 or 4 repetitions, each lasting about four seconds, nudging into the lumbar pain.

The pressure over the thoracolumbar joint makes a big difference, when knee flexion is very limited due to lumbar pain.
I do not understand exactly why this pressure helps; I am sure Diane would help with that one.

With one patient (only) it helped much more if she flexed and extended her neck as well. That does not work for everyone I have treated this way. like everything in physiotherapy, what works well for one person does not necessarily work for all.

Nari

[Diane]

The pressure over the thoracolumbar joint makes a big difference, when knee flexion is very limited due to lumbar pain.
I do not understand exactly why this pressure helps; I am sure Diane would help with that one.

Well, I'll be happy to try!
Nari, perhaps your pressure is doing one or all of the following:
1. lengthening the ab wall, lengthening fascia over anterior chest wall
2. pushing the origin of psoas closer to insertion of psoas
3. disengaging inhibition reflex of extensors of trunk
4. lengthening spine
5. providing novel afferent input to brain

Given that your treatment effect is immediate and continues after, I'll lay odds on "2" being the primary effect. The lumbosacral plexus lies within/weaves its way through the psoas on its way to the leg. I will go back out on a limb (I'm out there so frequently I should build a permanent treehouse..) ..and say that by pushing down on the mid back you are likely flossing the LS plexus through the psoas passively, but just enough to get it out of the position it was in from all the sitting the patient was doing as their "repetitive strain injury" to psoas and its contents..

Think about it. Psoas is continuously active in sitting. It is shortened in sitting. It contains the plexus. It will contract around the plexus and pull it up. The plexus contains among other things, the origins of the femoral nerve. Person gets up, but their psoas eventually doesn't elongate fully. The fascia over the quads is hooked into fascia over the psoas insertion. Futhermore, superficial thigh fascia is continuous with abdominal superficial fascia (I think it's called Scarpie's fascia).. I don't have a problem seeing how the whole system, pulling up from the knees and down from the abs, could get tightened into the anterior hips from sitting. Then when the person stands, they get dull back pain from feedback through the femoral and many other more cutaneous nerves in the inguinal area. Given time they get femoral nerve radicular pain and their back gets blamed: psoas, (which is firmly attached to discs) in its unlengthenable state pulls an annulus downward and the nucleus slides back, and lo, a bulge shows up. And the poor back is blamed or TrA, when in fact it was psoas all along being the unwilling culprit ("I was just following orders, honest!..")

Then you get them prone, and they have poor knee flexion. You press on their midback and lo, psoas suddenly moves closer to its insertion and the whole complex relaxes, including around the femoral nerve, and suddenly knee flexion is better. Now that the plexus is slidier within the psoas, the knee flexion remains better. Sounds like a treat for the patient! You are a hands-oner Nari! :)
Cheers,
Diane

[BB]

Nari,
Great info...can't wait to try it!

Diane,
I like your theory! I think you are right.

I wanted to add that I look for back pain with the prone knee bend also, and I pay attention to see what the pelvis is doing during the motion. Often times the pelvis tilts anteriorly with lumbar extension. The pain in this case can often be changed by pushing down on the pelvis to prevent the tilt. I have not had the carry over when I let go however. I have to teach them to actively keep the pelvis from moving. I look forward to using the treatment at the T-L junction!

Cory

[rolf]

Hi all!
Nice one Nari ,but have you tried to passive and active dors and plant.flex the anklejoint when you are doing the PKB mob.This can increase the mob.of the n .femoralis futher!
RIN

[nari]

Diane -

Thanks for your post, it does make sense. I find it interesting that on stiff, unyielding spines, I do not think I am lengthening anything much or altering the physical shape of the TLJ - much too stiff-but it is one of the 3 crucial 'hot spots' on the spine that David B talks about when he discusses neural tension.

Sometimes I do much more hands-on than usual, because the signs seem to indicate a further investigation, and I must admit admit my curiosity is increased; and when it backfires and I find much more than I want to know about, I sit back and look at the bigger picture.


BB - yes, the pelvis orientation is important. (McKenzie found this out).
Sometimes, during the knee flexion phase, the pelvis starts to rotate to avoid the increased tensioning, so I derotate manually and continue. It does have carry-over, because I teach the patient to recognise when rotation starts, and ask them to control it; as you have found.

Rin -

Yes, I do add DF and PF of the ankle, and sometimes, if it is indicated, eversion and inversion with DF. Once I got a positive for the lumbar pain with strong EV/DF at around 90 degrees knee flexion...and started to wonder what I was really affecting! (The same positive was not there when the patient was supine or prone).

Nari