Welcome to News You Can Use. Listen as Dr Ivo explains some twists in the standing tripod exercise.

Try it. Use it with your clients. Teach someone else

The partial truth about the Foot Tripod. The HEXApod.

The gait guys have talked about the foot tripod for a very long time. But the truth of the matter is that it is really a HEXApod. HEXA means 6. And when the foot is properly orientated and engaged on the ground, the 5 metatarsal heads and the heel should all be engaged with the ground, truly making it an asymmetrical hexapod. In an ideal scenario, the foot would be most stable if it looked like the strange symmetrical hexapod above with the contact points equally distributed around a center point. But that is not the human foot and this version of a hexapod is far simpler and likely inferior to the foot hexapod when human locomotion is to be attempted. The human foot is engineering marvel when it works properly.  

Perhaps the best example of what I mean by the foot being a HEXApod is in the pressure diagram above. In that first picture, on the right of that picture, we see multiple pressure points under the metatarsal heads of the right foot.  Minus the missing 1st metatarsal head pressure point (taken over by increased flexor hallucis longus activity represented by increased pressure at the big toe),  this pretty much confirms that the foot is not a tripod, rather a hexapod. The theory of the tripod, the 1st and 5th metatarsal heads and the heel, is only crudely accurate and honest. In this picture case, this person has increased lateral foot weight bearing (possibly why the 1st MET head pressure is absent) and possibly represented by pressure under the base of the 5 metatarsal. This is not normal for most people and if this person could get the 1st MET head down, they might even have a HEPTApod foot structure because of the 5th metatarsal base presentation (which sometimes represents peroneal muscle weakness). 

Where did we lead you astray after all these years of “tripod” talk ? We have always discussed the foot tripod. We have always discussed the imperative need to keep the limb’s plumb line forces within the area represented by the tripod.  If your forces fall more laterally within the tripod, as in this first discussed picture, one is at increased risk of inversion events and the myriad of compensations within the entire body that will occur to prevent that inversion. So again, why the tripod?  Well, it is easier to understand and it serves our clients well when it comes to finding active foot arch restoration as seen in this video of ours here.  But, the truth of the matter is that all of the metatarsal heads should be on the ground. The 2nd METatarsal is longer, the 3rd a little shorter, and the 4th and 5th even a little short than those. With the 1st MET shorter, these 5 form a kind of parabolic arc if you will. Each metatarsal head still should contact the ground and then each of those metatarsals should be further supported/anchored by their digits (toes) distally.  So the foot is actually more truly a HEXAPOD. Take the old TRIPOD theory we have always spoken about and extend a curved line beyond the forefoot bipod points (1st and 5th metatarsals) to incorporate contact points on the 2, 3 and 4th metatarsal heads. These metatarsals help to form the TRANSVERSE arch of the foot. It is this transverse arch that has given us the easily explainable foot TRIPOD because if a line is drawn between just the shorter 1st and 5th metatarsals, we do not see contact of the 2-4 metatarsal heads when we only look for pressure between these two bipod landmarks, but the obvious truth is that the 2-4 metatarsals are just longer and extend to the ground further out beyond this theoretical line drawn between the 1st and 5th MET heads.   

So, the foot is a HEXAPOD. Make no mistake about it. It is more stable than a tripod because there are more contact points inside the traditionally discussed foot tripod model. And frankly, the tripod theory is just a lie and just too fundamentally simple, unless you are an American 3 toed woodpecker.

Dr. Shawn Allen,     www.doctorallen.co

one of the gait guys

So, what’s in a test? The standing tripod test

Many of you probably recognize this as the standing tripod test (see here for video of standing tripod exercise). You have the individual stand on both foot tripods (center of calcaneus, head of 1st metatarsal and head of 5th metatarsal). Then have the person lift one leg and remain on the other tripod. This individual was featured in last thurdays post.

watch for:

collapse of arch

body lean

hip sway
falling to either side

spontaneous combustion (OK, this is a RARE complication).

What do we see here?

top picture, L leg

  • collapse of arch
  • forefoot eversion
  • valgus angulation of knee
  • pelvic shift to L
  • arm moves to compensate on right

middle picture, R leg

  • mild collapse of arch
  • pronounced pelvic shift to left
  • body lean to R
  • compensatory arm movement on L

Bottom picture

  • note the pronounced appearance of the head of the 1st met on the L foot
  • bilateral hallux abducto valgus most likely means bilateral uncompensated forefoot varus
  • more hammering (flexion) of digits on the R foot
  • note the prominence of the tail or tubercle of the 5th metatarsal on the L foot

Some questions for you:

Q: why does he have a pelvic shift to the left in both r and L leg standing?

A: look at the feet. He is able t make a better tripod on the L foot, probably because of the prominence of the head of the 1st metatarsal. also note the valgus angulation of the knee, which helps to shift the center of mass to the midline. this is most likely a long term compensation

Q: Why does he have more body lean to the R during r leg standing?

A: see previous question AND he probably has weaker hip abductor muscles on the right

Q: did you notice that the hand and forearm were more supinated in the top (L standing) picture than the middle (r standing) picture (where he is more pronated)? What gives?

A: Wow, this is some subtle stuff, eh? Look to the brain. remember coordinate arm swing? (if not, look here and here) Supination accesses more of the extensors of the arm and pronation more of the flexors. When we have less extensor activity (remember flexor dominance? if not, click here) you have a tendency to use your flexors more to compensate (you use what you have available to you). It appears that he has a much tougher time standing on his r leg (judging from the increased compensation)

Q: Wow,  nice floors! Are they hardwood?

A: No, laminate

The Gait Guys. Helping you help others each and every post. Keep your eyes and your mind open : )

How good is your tripod? Looks can be deceiving

You have heard us here on the blog talking about the foot tripod. For those of you who may not remember; click here and here for a refresher.

In the right foot (far left image) pedograph, you notice increased ink under the three points of the tripod (pass your mouse or click on the image to enlarge): The center of the calcaneus, the head of the 1st metatarsal and the head of the 5th metatarsal. Looks pretty good, correct ? The left one (center image) shows more weight on the lateral aspect of the foot.

Note now the picture of the feet that go with this tripod (far right). Pretty scary, huh ? Their left foot actually looks like a better tripod, especially the medial tripod.  So, what does that tell you? It tells you that from the pedograph print (remember the person is walking across the pedograph), they are able to compensate better on the right than on the left.  Remember what we always say, what you see is not what is wrong or what is actually truthfully going on.

So, what do you do?

consider exercises to increase the foot tripod (tripod standing, the Extensor hallucis brevis exercise,  lift spread reach ) and try and make the weight distribution equal from side to side.

The Gait Guys. Making sure you are firing on all your cylinders (or walking on all 3 points of the tripod). 

Want to know more? Consider taking the 3 part National Shoe Fit Program. Email us at thegaitguys@gmail.com for more details. 

Podcast #31: Walking Straight, Mastalgia & Shoes

podcast link:

http://thegaitguys.libsyn.com/podcast-31-walking-straight-matalgia-queen

iTunes link:

https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

Gait Guys online /download store:

http://store.payloadz.com/results/results.aspx?m=80204

other web based Gait Guys lectures:

www.onlinece.com   type in Dr. Waerlop or Dr. Allen  Biomechanics

Today’s show notes:

1. Neuroscience Piece:

http://www.cell.com/current-biology/abstract/S0960-9822(09)01479-1

http://www.npr.org/blogs/krulwich/2011/06/01/131050832/a-mystery-why-can-t-we-walk-straight

Today we have a neuroscience piece on “turning”, in a matter of speaking. So why, when blindfolded, can’t we walk straight?

These “Turning” field studies appear in Chris McManus’ book, Right Hand, Left Hand, The Origins of Asymmetry in Brains, Bodies, Atoms and Cultures (Phoenix, 2002). 

NPR Story Produced by Jessica Goldstein, Maggie Starbard.

2. neuroscience 2 at the end of the show.

The myth of the 8 hour sleep
3. Blog reader asks:
Any shoe recommendations for an uncompensated forefoot varus?

4. and another from the Blog:
Hi The Gait Guys, what can I do to regain medial tripod? I have a forefoot varus and when I am standing it compensates and my rearfoot everts and gets valgus. I have been having some pain lately and it is annoying me a lot. Please help. Thank you.
5. FACEBOOK readers asks:

Bringing the Foot Back To Life: Restoring the Extensor Hallucis Brevis Muscle.

http://youtu.be/1iZg_e4veWk

6. PUBMED

Foot loading patterns can be changed by deliberately walking with in-toeing or out-toeing gait modifications.

Gait Posture. 2013 Apr 25. pii: S0966-6362(13)00190-2.

7. The Gait Guys are always talking about ankle rocker, dorsiflexion strength and the importance of the anterior compartment of the lower leg. Here is another study to add fuel to our fire.

Ankle dorsiflexor strength relates to the ability to restore balance during a backward support surface translation

Gait & Posture

—————

8. Shoes:

NB new Minimus 10V2

The Minimus 10 is back – and better than ever. The MR10v2 is the latest version of the previous Minimus Road 10,



9.
http://www.runnersworld.com/health/study-one-third-female-marathoners-report-breast-pain

Study: One-Third of Female Marathoners Report Breast Pain

10. Painkiller meds taken before marathons

http://www.labspaces.net/127827/Painkillers_taken_before_marathons_linked_to_potentially_serious_side_effects

from the British Medical Journal

11. The myth of the 8 hour sleep

http://www.bbc.co.uk/news/magazine-16964783
By Stephanie Hegarty BBC World Service

One simple hip screen that gives you lots of information.

This is the one leg standing test. We use it as a hip function (abduction) screen(as well as an exercise), to see if a person’s gluteus medius is working in a functional situation (as opposed to manual muscle testing).

As you may remember (don’t remember? Click here), the gluteus medius fires throughout stance phase (ie; when the foot is on the ground). It keeps the pelvis level while the foot is on the ground and works in conjunction with the opposite quadratus lumborum muscle (if you have not read up on this, please see our groundbreaking work on the problematic cross over gait, found here, here and here).

The test is simple; try it on yourself while watching yourself in a mirror. Stand on one leg on your foot tripod (the heel, base of big toe and base of little toe). Raise the opposite foot off the ground by flexing the thigh. Observe.

You should see the pelvis remaining level with no shift of the torso or hips. 

Watch for:

  • ·      Pelvic drift to the side you are standing on
  • ·      Pelvis drop on the side opposite you are standing on
  • ·      Body lean to the side you are standing on
  • ·      Excessive hiking of the opposite, non weight bearing hip
  • ·      Any combination of the above

 

Seeing any (or all) of these means the gluteus medius is probably having some trouble.  The reason we say probably is that a person with a hip problem (like arthritis) or an anatomically short leg may do some of these things in compensation.

The question you are hopefully asking is why do they drift, lean, hike, etc? Not everything you see is muscle weakness per se.

  • ·      Maybe they have a balance issue
  • ·      Maybe they have a disc injury
  • ·      Maybe they have injury to the nerve going to the gluteus medius
  • ·      Maybe they have a knee/ankle/foot issue
  • ·      And the list goes on…

So, if it were a muscle weakness, how could you fix it? Determine the cause. Begin at the bottom with foot exercises: tripod standing, lift/spead/reach with the toes etc. Then have them repeat the exercise IN A MIRROR, maintaining a level pelvis. Yes, it is that simple. Now see if they can translate that to their gait cycle. If so, great. If not, start again and repeat till they can.

The Gait Guys. Making it real, each and every day.

all material copyright 2013 The Gait Guys/ The Homunculus Group. All rights reserved. Please ask before using!

“I’ll plead the 1st … .”   More foot geek stuff from The Gait Guys.

The 1st Ray that is!

The “1st ray” consists of the 1st metatarsal and the medial cunieform, essentially the long bones associated with the big toe. It is a functional unit we often refer to when discussing foot biomechanics.

You have heard us speak of the 1st ray needing to descend to form the medial tripod of the foot (tripod review: head of 1st metatarsal, head of 5th metetarsal, center of calcaneus). This action depends to some degree on the competency of the peroneus longus, which attaches from the upper lateral fibula and the associates interosseous membrane; curves around the lateral malleolus, crosses under the foot and attaches to the base of the 1st metatarsal and medial cunieform. The tibialis posterior is supportive to this action. This action is opposed (or modulated, for every Yin there is a Yang; it’s all about balance) is the tibialis anterior, which attaches to the top of the base of the 1st metatarsal and 1st cunieform.

As a result, 1st rays can be elevated or depressed. (here is a latin term to impress your friends with: Metatarsus Primus Elevatus, or elevation/dorsiflexion of the 1st ray/metatarsal). Clinically, we see more that are elevated, resulting in a faulty (collapsing) medial tripod of the foot. The important thing is isn’t necessarily its position, but rather its flexibility. The inflexible ones (isn’t it always?) are the problem children, because they result in altered (notice I didn’t say bad) biomechanics. The further we move from ideal, the closer we seem to move to some compensation pattern. The flexible ones are still a problem but we can control and dampen their rate of flexible collapse.

Generally speaking, a plantar flexed 1st ray that is rigid, has a tendency to throw your center of gravity (an often your knee) to the outside of the foot tripod (think of a rigid cavus foot) and a dorsiflexed to the inside of the foot tripod. Sure, there are LOTS of other factors, but we are talking in generalities here.

Look carefully at the images above and note the position of the 1st metatarsal heads. In the top set, the 1st is depressed (or plantarflexed). In the bottom set they are elevated (or dorsiflexed). Cool, eh? 

NOTE: please refrain from using the term “dropped metatarsal”. Nothing gets dropped, it is correctly stated as plantarflexed (rigid or flexible).

Be on the look out for these on your clinical exam.

Ivo and Shawn. Bringing you one step closer to foot geekdom each day!

copyright 2012 The Homunculus Group/The Gait Guys. All rights reserved. If you rip off our stuff, you will be plagued with the curse of Toelio…..