Midtarsal Joint Equilibrium Theory

Simon:

I will hopefully be seeing Ryan Chang at the iFAB meeting in Seattle next week (along with many other of my favorite biomechanists) and will try to ask him about his research which I saw him present at the PFOLA meeting from a few years ago. I don't know if this in-phase, anti-phase movement of the rearfoot and forefoot that him an Joe Hamill were working on has any clinical significance. I'll try to talk to both Ryan and Joe about it at the meeting for you since I know you will be doing much more important things than attending this once- every-other-year meeting of the smartest foot and lower extremity biomechanists in the world.............

 

I'd appreciate that, Kevin. It's a shame I can't be there. But I'll be in excellent company in Paris and at the edge of the stage at this:

 

Looks like fun. Who or what is it?

BTW, I recently went back and started to research some of the concerts I went to in the 70's. Kind of explains the hearing loss! One of my favorites was when the opening act for Ann Murray was a young artist by the name of Billy Joel. That was my first rock concert ever! Then, Greatful Dead, Beach Boys, Doobie Brothers, Joe Walsh, Chicago, Fleetwood Mac, Elvin Bishop, Frampton, Eagles, Zeppelin, Leonard Skynyrd, Jeff Beck, CSNY, James Taylor, etc., etc.

This might also explain the memory loss, now that I think about it. The 70’s were a great time for music!

 

Nice CV, Jeff. The above picture is the "claw" stage from the U2- 360 degree tour. Saw it last year at Wembley Stadium, awesome. Next weekend: Paris here we come! I started going to concerts at an early age: Iron Maiden when I was about 10, Hawkwind around the same time, Black Sabbath, Motorhead, Judas Priest, Rush at about age 11 or 12, Kiss at 13... I saw U2 on the War tour in 1983 (age 13), I've seen them on every tour (at least once) ever since.... Lost count of the number of bands I've seen, but I'm still jealous of your list Jeff.

 

I was fortunate enough to live an hour's drive from the Oakland Coliseum and the Day on the Green Concert series. We had a youth pastor who was a bit of a hippie type and had lived with Tom Johnston of the Doobie Brothers. We were driving around listening to “Old Black Water” on his eight track before the album was released. My buddies and I would sing it around school and everyone else wanted to know what the heck we were singing.

 

Legendary! I am familiar with the "day on the green" concerts. Looking at the bands you listed- 1975. In my collection I have a "day on the green" t-shirt featuring U2 from Joshua tree era (1987), with the bands faces replaced by those of dogs. I didn't attend it, I collect vintage tour shirts. You are legend, Bob.

For those unfamiliar with "day on the green":
http://en.wikipedia.org/wiki/Days_on_the_Green

 

Simon and Jeff:

The only rock concert I ever attended was Day on the Green #1 when I was 16:

Day On The Green #1: Leon Russell, Loggins and Messina, Elvin Bishop, Merry Clayton (August 5, 1973).

Me and a friend went mostly to see Leon Russell. I was (and still am) also a Joe Cocker fan. Leon Russell organized the Mad Dogs and Englishmen tour. Great album!

 

My son's high school Spanish teacher (last year) worked for Bill Graham who was the concert promoter and founder of Bill Graham Presents. His teacher got married at Bill Graham's home not long before Graham was killed in a helicopter crash in 1991. He toured all over the U.S. for concerts with the company. I'm sure he could tell a few stories!

 

Back from a computer free weekend - Came back to see whats going on - Click on here o see what brain workout Ive got coming for me and we have my favouate past time being discussed music - listening that is.

This thread is a classic Pod arena thread - Brain hurting biomex discussion ( well is was for me, and hopefuly more when Kevin reports back, with some random discussions about whatever, in this case new born babies and 1970´s rock concerts - great stuff)

 

Bill Graham = Legend.

 

I was there too! I was the guy with the long hair and the wild shirt on. Don't you remember me?

 

Now you're just showing your age and hippy pasts guys. Really. Was that you with the blanket wrapped around you on the Woodstock cover? Or maybe one of you was the model for the artwork in "the Joy of Sex"..... I dread to think.

 

Hi Kevin , Simon and Jeff
I was following this thread on the MTJ and I was more interested when I saw the last few posts on concerts.
Growing up in Toronto we were blessed with to see many home grown artists. For instance I have seen Neil Young and Gordon Lightfoot many times. Jeff in 1974 I saw RUSH at a high school dance, before they started touring the US.
I belonged to a club called Cheap Thrills that Concert Productions International put together, it allowed you access to the same seat for every concert for $100 per year. A seat license the more I think about it now.
Concents were held at Massey Hall or Maple leaf Gardens I was privileged to see Bob Dylan, Peter Frampton, The WHO, Supertramp, and Genesis.
Simon I saw U2 at Massey Hall(2000 seats) in November 1983 and at Maple Leaf Gardens(17,000 seats) only 5 months later when U2 really became big. The best concert was the Clash in 1984 at Maple Leaf Gardens. I have also seen Simple Minds.

I have to agree the 70's and early 80's were awesome. I don't get to many concerts now. I was suppose to go to the U2 concert in July 2010 but was cancelled due Bono's back surgery. It has been rescheduled for July 2011. This has brought back great memories
Thanks

 

Hi Peter,

Great to hear from you again! Sounds like you saw some great shows. Bob Dylan! Nice!

Both of my son's like my generation's music, plus some country and a few other things but fortunately not rap. When I recently showed my oldest son the partial list of concerts I attended he first said "cool" and then asked, how much would it cost in today's dollars? Kids these days, where are their priorities?

I worked through most of high school and my dad would say "jeff, you're just pissing your money away" when I would buy music or go to concerts. I'm glad I didn't listen to him!

Cheers,
Jeff

 

I was able to talk to Ryan Chang yesterday here at i-FAB in Seattle. Ryan said what he has found from his research on rearfoot-forefoot coupling was that the individuals with more normal gait patterns had more anti-phase motion of the rearfoot and forefoot than did the abnormals. However, Ryan also stated that he wasn't sure what the clinical significance of this finding was. He did agree with me that possibly anti-phase motion of the forefoot and rearfoot may be the preferred kinematic patterns of the foot. He said that in-phase and anti-phase motions of the rearfoot and forefoot is highly variable not only from one individual to another but also depending on where in the stance phase of gait one is measuring the kinematics of the forefoot and rearfoot.

I am sending Ryan a link to this page so that maybe, if he has time, he can comment directly on his research.

Hope this helps.

 

For which locomotor function? Forward walking on a flat level surface? What about changing direction and swerving left or right?

 

Forward walking on flat level surface.

 

Thanks, Kevin. So the question then becomes what factors would determine whether the motion is in-phase motion as oppose to anti-phase motion at the forefoot and rearfoot? I've given some of my thoughts earlier in this thread. What are your thoughts, Kevin?

 

Sorry folks a little confused.

Your saying that anti-phase maybe more normal, but Chang made this conclusion.

so maybe it´s more to do with timing of in-phase and anti-phase during the gait cycle.?

 

I think it's about what is happening and when.

 

I told Ryan that I thought anti-phase motions of the forefoot and rearfoot would seem normal during midstance, which he agreed with. However, he said the motions depend on the phase of gait and the individual and which cardinal plane the motion is occurring in. We only talked for about 5 minutes and I did send him an e-mail and spoke to him about possiblyy coming onto Podiatry Arena to comment.

 

Hi there. Interesting discussion you are having. I compared plantar fasciitis feet and healthy feet in level walking. I initially thought that more anti-phase movements would be detrimental to the plantar fascia (torsion, tension and bending). Interestingly, we found the opposite. Here's an excerpt from my dissertation concerning what you are discussing (I'll be publishing these data shortly). Let me know if you have any questions:

"These data did not support the hypothesis that plantar fasciitis individuals exhibit greater anti-phase movements, and in fact, the opposite was found – plantar fasciitis feet are associated with reduced anti-phase movements. These findings, however, are consistent research on upper body coordination. Reduced anti-phase movements and increased inter-segmental rigidity of the pelvic-thoracic segments has been reported in Parkinsonism (Van Emmerik et al., 1999) as well as chronic low back pain (Selles et al., 2001; Lamoth et al., 2006). It has been speculated that lesser anti-phase motion is indicative of guarding behavior against pain. Lamoth et al. (2006) reported increased and more erratic lumbar muscle activity,which may impair inter-segmental coordination and increase rigidity. Such pain guarding strategies and increased muscle activity might also play a role in reducing anti-phase motions in plantar fasciitis individuals. It is proposed that anti-phase motion of the rearfoot and forefoot is functional and allows for fluid movements in gait."

 

Ryan:

Thanks for getting back to us on your research. As I mentioned to you in our discussion at the i-FAB conference, it is traditionally taught in podiatric biomechanics that, normally, in the frontal plane that rearfoot eversion will be accompanied by forefoot inversion, that in the sagittal plane that rearfoot plantarflexion will be accompanied by forefoot dorsiflexion and that in the transverse plane that rearfoot adduction will accompanied by forefoot abduction (i.e. anti-phase motions of the rearfoot and forefoot in the three cardinal body planes). It makes sense that anti-phase motions are necessary to allow fluid movement transfer between the proximal and distal segments of the foot.

Have you looked at anti-phase in-phase movements with any pathologies other than plantar fasciitis??

 

Hi Ryan thanks for joining in - I look forward to seeing the paper.

so point 1. anti-phase motion is more normal as you say " It is proposed that anti-phase motion of the rearfoot and forefoot is functional and allows for fluid movements in gait"

and point 2. in a paient we with a pain response we may see more in-phase motions.

if we break this into steps

step 1. no plantarfascia pain - more anti-phase motion rearfoot to forefoot.

step 2. ???????

step 3. plantarfascia pain - increase in in-phase motion rearfoot to forefoot.

 

Ryan, thank you for taking the time to come onto Podiatry Arena to discuss you work.

You state above that plantar fasciitis feet were associated with reduced anti-phase movements, yet in the article I cited previously you stated: "Chronic plantar fasciitis feet exhibited greater peak rearfoot-forefoot angles in the sagittal and frontal planes and more frequent anti-phase movements in the loading phase of gait compared to healthy feet."

Why this apparent discrepancy?

 

And there lies the problem Kevin, the axes of motion for the MTJ which Nester reported at times should result in tri-plane movements that are neither pronation nor supination. If we agree that the STJ either pronates or supinates, then when the STJ is pronating the forefoot should be doing the opposite to be anti-phase, i.e. inverting , plantarflexing and adducting, yet the axes of the MTJ determined by Nester would not allow this. Now, that's just the STJ and not the entire rearfoot, so we need to think about the coupling between ankle and STJ motion too.

Additionally, why should it make anymore sense to have anti-phase motion to allow fluid movement transfer than to have in-phase motion? If we took a wheel with a tyre on it we wouldn't want the wheel to spin clockwise while the tyre moved anti-clockwise to allow fluid movement transfer and forward motion...?

 

Simon:

The motions that I reported were using the three reference axes that Nester reported and these make complete sense for the midstance phase of gait where the proximal rearfoot and distal forefoot are stablized by friction with the ground. However, I would agree that anti-phase motions are not so necessary for contact phase and propulsion. By the way, your tire (tyre) analogy is not a good mechanical analogy for the foot....never saw a foot rolling down the road......have you?

 

But it is contradicted by Nester's kinematic data, which is what I was referring to. Also even with the use of a 3-orthogonal axis system, the motion occurring at the rearfoot and forefoot may or may not be in-phase depending on where the net ground reaction force vector is in relation to the STJ axis and the three orthogonal MTJ axes. This is what I was attempting to show earlier in this thread. As for the tyre, it was the first thing I thought of and may not be the best analogy, but you could argue given Perry's three rocker's, and sagittal plane facilitation theory, that the foot kind of rolls in the sagittal plane through contact.

I still don't understand why you think anti-phase motion should result in a "more fluid movement transfer"?

 

This poster from Pohl suggests that frontal plane motion is not coupled between rearfoot and forefoot:
http://www.eng.brad.ac.uk/research/mrs_projects/buckley/Salford_Poster.pdf

Nor this paper:
http://www.ncbi.nlm.nih.gov/pubmed/16759862

Which is interesting when we see results like this:
http://www.staffs.ac.uk/isb-fw/Manuscr/Nurse11.pdf

 

But the Pohl paper did suggest that some motions are coupled

One set of motions has the posibilty to be in-phase ie rearfoot - forefoot inversion-eversion

But frontal plane motion of the rearfoot coupled with forefoot sagittal and transverse which would mean coupling and anti-phase motion . ???

 

I need to go back and look at the Pohl data, where the coupled motions in-phase or anti-phase?
Forefoot to rearfoot plantarflexion / dorsiflexion was in-phase.

Shank to forefoot int /ext, add / abd were in phase.

 

Simon,

Here is my take on it. During closed chain stj pronation, the talus adducts and plantarflexes and the calcaneus everts. If so, then the forefoot abducts, dorsiflexes and inverts. The motion of the forefoot is triplane motion but it is not supination or pronation per se. Why?

When you have closed chain dorsiflexion of the medial column relative to the lateral column, it produces relative inversion of the forefoot! So inversion of the forefoot is not necessarily a varus "twist" at the mtj (i.e. not pure frontal plane inversion motion).

Jeff

 

Simon I maybe getting it a bit mixed up.

but my thinking was that if you have rearfoot frontal plane motion couple with forefoot sagittal and transverse plane - it was meaning that when the rearfoot was going through the motion of abduction or adduction the coupling effect would mean that there was inversion or eversion and dorsiflexion or plantarflexion occuring, which would indicate anti-phase motion, but I could be completly wrong.

 

Hi Jeff I know you addressed Simon, but if I may.

your above example maybe the case sometimes and others not - As the STJ pronates we will have the talus adducts and plantarflexes and the calcaneus everts as you state but we may have motion around the midtarsal joint that may or may not be tri plane and may or may not be what we refer to as pronation and supination.

we can have and combinations of any one from the 3 lines below in relation to nesters x,y,and z axis

adduction - no movement - abduction
inversion - no movement - eversion
plantarflexion - no movement - dorsiflexion

this will be decided by where the MTJ axis is situation in relation to what is driving the STJ moment of pronation external moment and or internal moments

 

I agree. It can also:
dorsiflex and invert, but not ad or abduct
dorsiflex and evert, but not ad or abduct
and more!

 

Look at the kinematic graphs in the Pohl poster I linked above. When the rearfoot is plantarflexing, the forefoot is plantarflexing and vice versa = in-phase, etc.

 

Jeff, I think the key is in how we segment the foot (this is what Erin Ward was trying to figure out the last time I saw him, a few years ago now) but if the segments are: 1) rearfoot and 2) forefoot... it's a pretty broad view. Personally, I'm still uncomfortable with the MTJ being treated as one joint.

 

I see that the whole joint coupling of rearfoot to forefoot in different body planes with in-phase, anti-phase thing got me confused.

Story of this thread all good though :drinks

 

I've been thinking about this since you posted it, you're gong to have to help me out here: why do think "it makes complete sense" for the forefoot and rearfoot to be anti-phase during midstance?

 

I totally agree. When the long axis of the talus adducts relative to the long axis of the calcaneus during closed chain stj pronation, the nature of motion at the ball and socket like talonavicular joint is quite different than the simultaneous motion that occurs at the more restricted calcaneocubiod joint. This is why the medial arch of the foot, via medial column motion can change shape far more than the lateral column or lateral arch. The midtarsal joint is a convenient clinical description of two joints, but for more in depth scientific research and discussion purposes, it is highly lacking. Let me give you an example.

Here is how we could possibly describe closed chain stj pronation. The talus adducts and plantarflexes on the calcaneus. The calcaneus everts along with cuboid as the cuboid dorsiflexes at the cc joint. The talus adducts and plantarflexes relative to the navicular. Conversely, we can also say that the navicular abducts and dorsiflexes relative to the talus. So in this scenario, we have uniplane motion at the cc joint (cuboid dorsiflexion) and biplane motion at talonavicular joint (navicular abduction and dorsiflexion). There could also be inversion of the navicular to the talus occurring, so it could be possible to have triplane motion at the tnj and simultaneous uniplane motion at the ccj when the calcaneus and cuboid evert as a unit.

Does that make sense to you?

Jeff