Don't let them fool you. Thoughts on gait analysis programs, force plates etc.

Accuracy of gait analysis programs and software.
This is not meant, by any means, to be an exhaustive or comprehensive review of gait analysis programs or software. To be truthful, we here at TGG have abandoned all of the software programs well over a decade ago, programs that we initially used to help us slow the gait down, measure joint angles and other seemingly valuable parameters. As time ticked on, we realized that we had trained our eyes to see most of what the software was telling us, and we also began to value the third visual dimension that these types of programs were thin on. Then came ipads and iphones and the ability with a mere finger to slow down someones gait, reverse it and play forward again. This was all we needed, and this next statement is key, for what we do for our clients.

We were pleased to see the repeatability and consistency in the data and results as outlined in these 2 selected studies. If someones gait problem is repeating, and the software is consistent, the data should be repeatable. But, here it comes, what you see in someones gait is not their problem, it is their habitual pattern of possible dysfunction. There, we said it again, for the 1000th time. Software has limited value in fixing someones problems, it merely presents data points to quantify the gait they present with. And if the client has pain, the software consistently shows the gait pattern that presents with their problem. Changing their gait does not mean you have remedied their problem, you may have, but you are more likely to have asked them to generate a new compensation around a problematic gait. A compensation around a compensation if you will.

Force plates, pedographs, and the like also fall into this data capture category. These are all tools, tools for gathering information that must be folded into hands-on clinical examination information. One needs all of the pieces if they are to play this game right, using just some of them and negating others is abusing the value of each piece data. And, the result of implementing corrective change without all the pieces is gambling that you have enough data to do it right. So, when did this become a game of gambling ?

Gait Posture. 2016 Jul;48:194-201. doi: 10.1016/j.gaitpost.2016.05.014. Epub 2016 May 25. Accuracy and repeatability of two methods of gait analysis - GaitRite™ und Mobility Lab™ - in subjects with cerebellar ataxia.
Schmitz-Hübsch T1, Brandt AU2, Pfueller C3, Zange L3, Seidel A3, Kühn AA4, Paul F4, Minnerop M5, Doss S3.

Biomed Res Int. 2014; 2014: 348659.
Published online 2014 Feb 20. doi: 10.1155/2014/348659
PMCID: PMC3950554. Accuracy and Repeatability of the Gait Analysis by the WalkinSense System.
Marcelo P. de Castro, 1 , 2 , 3 ,* Marco Meucci, 4 Denise P. Soares, 1 , 3 Pedro Fonseca, 3 Márcio Borgonovo-Santos, 1 ,3 Filipa Sousa, 1 , 3 Leandro Machado, 1 , 3 and João Paulo Vilas-Boas 1 , 3

A Tale of 2 Footies

Time for a pedograph, folks. What do we have here?

To review :

Let’s divide the foot into 3 sections: the rear foot, the mid foot and the fore foot.

First of all, are they symmetrical? Look carefully at the fore foot on each side. NO! the right foot looks different than the left, so we are looking at asymmetrical pathology.

Let’s start at the rear foot: The heel teardrop is elongated on both sides, slightly more on the right; this means incraesed calcaneal eversion (or rearfoot pronation) bilaterally, R > L. The right heel shows increased pressure (more ink = more pressure).

Next up, the mid foot. Similar shapes, more pressure and printing on the left. Did you notice the “tail” of the 5th metatarsal printing, giving it a wider print? This person is staying on the outside of their foot longer than normal, right (more ink) more than left.

How about the fore foot? Lots going on there.

Lets start on the left

Notice the mild increased printing of the 5th and 4th metatarsal heads. Force should be traveling from lateral to medial here, as the foot goes into supination. A relatively normal amount of pressure on the head of the 1st metatarsal.

Now look at the toes. Notice that space between the 2nd and 3rd? This gal had an old fracture and has an increased space between them.

Now how about the right?

Increased pressure on most of the heads with a concentration on the 1st metatarsal. Hmmm…what would cause that? this is typical of someone who has a 1st ray (cunieform and metatarsal) that is hypomobile, such as with someone with a forefoot valgus (as this person does) or a dropped 1st metatarsal head (which is usually rigid, as is NOT the case here).

Did you see that rpinting at the medial aspect of the proximal phalanyx of the hallux (ie. big toe)? This gal externally rotates the lower extremity to push off the big toe to propel herself forward. This is because the 1st metatarsal head hits the ground BEFORE the 5th (as we would normally expect to see, like in the left foot), and because the weight is now on the outside of the foot, she need to push off SOMETHING.

Getting better at this? We hope so. Keep reading the blog and look at some of our past pedograph posts here.

The Gait Guys. Teaching you about the importance of gait, each and every day!

What’s up, Doc?

Nothing like a little brain stretching and a little Pedograph action.

This person had 2nd metatarsal head pain on the left. Can you figure out why?

Let’s start at the rear foot:

• limited calcaneal eversion (pronation) L > R. The teardrop shape is more rounded on the left. This indicates some rigidity here.
• note the increased pressure at the  medial calcaneal facets on each side with the increased printing
• very little fat pad displacement overall

Now let’s look at the mid foot:

• decreased mid foot pronation on the L. See how thin the line is going from the rear foot to the forefoot along the lateral column? This indicates a high lateral longitudinal arch

Now how about the fore foot?

• increased printing under the met heads bilaterally; L >> R
• increased printing of 1st met head L >> R
• increased printing at medial proximal phalynx of hallux  L >> R
• increased printing of distal phalanges of all toes L >> R

 Figure it out?

What would cause increased supination on the L?

• short leg on L
• more rigid foot on L
• increased pronation on the R

Did you notice the elongated 2nd metatarsals (ie: Morton’s toe) on each foot?

Here is what is going on:

• there is no appreciable leg length deformity, functional or anatomical
• The Left foot is more rigid than the Right, thus less rear, mid and fore foot pronation, thus it is in relative supination compared to the right foot

do this: stand and make your L foot more rigid than the right; take a step forward with your right foot, what do you notice?

• Can you feel how when your foot is supinated
• can you see how difficult it is to have ankle rocker at this point? remember: supination is plantar flexion, inversion and adduction
• Can you feel the weight of the body shift to the outside of the foot and your toes curl to make the foot more stable, so you do not tip to the left?
• now, how are you going to get your center of mass forward from here? You need to press off from your big toe (hallux)

Wow, does that make sense now?

What’s the fix?

• create a more supple foot with manipulation, massage, muscle work
• increase ankle rocker by training the anterior compartment (shuffle walks, lift/spread/reach exercise, heel walking, Texas walk exercise, etc)
• have them walk with their toes slightly elevated
• we are sure you can think of more ways as well!

The Gait Guys. Increasing your gait literacy with each and every post. I

The deeper your knowledge and experiences, the more things you will see. As in life, the more experiences you have the wiser you become and the clearer the bigger picture becomes. All these things enrich the experience or observation. These experiences take simple black and white and render an infinite palate of grey tones. 

To the untrained observer, these are just two feet. With a little more experience these are two feet of different length. Deeper further, these are two different sized feet with different plantar pressure responses (helped here by increasing the greyscale contrast). Deeper yet, this represents a left foot (viewers right) that has a dysfunctional flexor digitorum longus (FDL) and lateral quadratus plantae muscle. All of these observations allow the skilled and knowledgeable viewer to extrapolate and theorize, with clear thought processes, which leg could be shorter/longer, how the pelvis might be distortioned, step length and stride length variability, foot stability and so much more.

The life long student does not need the contrast enhanced picture on the right to heighten the visibility of the plantar pressures, but it helps.  This is what wisdom and experience do, they enable you to look deeper into something and to see it for what it truly is, not what it appears to be.

Come listen to our teleseminar tonight (Wednesday March 18th, 2015) on www.onlinece.com at 7pm central. Log in early to get set up. Come listen in while we delve into one of the bigger questions, if the left foot (viewers right) is longer it has likely pronated more over a longer period of time stretching out plantar soft tissues and corrupting joint function in multiple areas. But if this is the case, why then are they presenting with plantar pressures that are more representative of supination standards ?  

This is mental gymnastics. It is good stuff to do regularly, even though this is a static presentation, many good theories and thoughts can be brought forth. Getting the answer is not the goal, getting the thought process down is.

The more you know, the more truth you will see.

See you tonight, we will break this down into a microscopic level that will challenge you all.

Shawn and Ivo, the gait guys

Part 2: “Standing on Glass” Static Foot/Pedograph Assessment

* note (see warning at bottom): This is a static assessment dialogue. One cannot, and must not, make clinical decisions from a static assessment. The right and left sides are indicated by the R and L circled in pink. There are 4 photos here today.

Blue lines: Last time we evaluated possible ideas on the ORANGE lines here, it would be to your advantage to start there. 

We can see a few noteworthy things here in these photos. We have contrast-adjusted the photo so the pressure areas (BLUE) are more clearly noted. There appears to be more forefoot pressure on the right foot (the right foot is on the readers left), and more rearfoot pressure on the left (not only compare the whiteness factor but look at the displacement of the calcaneal fat pad (pink brackets). There is also noticeably more lateral forefoot pressure on the left. There is also more 3-5 hammering/flexion dominance pressure on the left.  The metatarsal fat pad positioning (LIME DOTS represent the distal boundary) is intimately tied in with the proper lumbrical muscle function  (link) and migrates forward toward the toes when the flexors/extensors and lumbricals are imbalanced. We can see this fat pad shift here (LIME DOTS). The 3-5 toes are clearly hammering via flexor dominance (LIME ARROWS), this is easily noted by visual absence of the toe shafts, we only see the toe pads. Now if you remember your anatomy, the long flexors of the toes (FDL) come across the foot at an angle (see photo). It is a major function of the lateral head of the Quadratus plantae (LQP) to reorient the pull of those lesser toe flexors to pull more towards the heel rather than on an angle. One can see that in the pressure photos that this muscle may be suspicious of weakness because the toes are crammed together and moving towards the big toe because of the change in FDL pull vector (YELLOW LINES). They are especially crowding out the 2nd toe as one can see, but this can also be from weakness in the big toe, a topic for another time. One can easily see that these component weaknesses have allowed the metatarsal fat pad to migrate forward. All of this, plus the lateral shift weight bearing has widened the forefoot on the left, go ahead, measure it. So, is this person merely weight bearing laterally because they are supinating ? Well, if you read yesterday’s blog post we postulated thoughts on this foot possibly being the pronated one because of its increased heel-toe and heel-ball length. So which is it ? A pronated yet lateral weight bearing foot  or a normal foot with more lateral weight bearing because of the local foot weaknesses we just discussed ? Or is it something else ? Is the problem higher up, meaning, are they left lateral weight bearing shift because of a left drifted pelvis from weak glute medius/abdominal obliques ?  Only a competent clinical examination will enlighten us.

Is the compensation top-down or bottom up, or both in a feedback cycle trying to find sufficient stability and mobility ? These are all viable possibilities and you must have these things flowing freely through your head during the clinical examination as you rule in/rule out your hands-on findings.  Remember, just going by a screen to drive prescription exercises from what you see on the movement screen is not going to necessarily fix the problem, it could in fact lead one to drive a deeper compensation pattern. 

Remember this critical fact.  After an injury or a long standing problem, muscles and motor patterns jobs are to stabilize and manage loads (stability and mobility) for adequate and necessary movement. Injuries leave a mark on the system as a whole because adaptation was necessary during the initial healing phase. This usually spills over during the early movement re-introduction phase, particularly if movement is reintroduced too early or too aggressively.  Plasticity is the culprit. Just because the injury has come and gone does not mean that new patterns of skill, endurance, strength (S.E.S -our favorite mnemonic), stability and mobility were not subsequently built onto the apparently trivial remnants of the injury.  There is nothing trivial if it is abnormal. The forces must, and will, play out somewhere in the body and this is often where pain or injury occurs but it is rarely where the underlying problem lives.

Come back tomorrow.  We will try to bring this whole thing together, but remember, it will just be a theory for without an exam one cannot prove which issues are true culprits and which are compensations. Remember, what you see is often the compensatory illusion, it is the person moving with the parts that are working and compensating not the parts that are on vacation.  See you tomorrow friends !

Shawn and ivo, the gait guys

* note: This is a static assessment dialogue. One cannot, and must not, make clinical decisions from a static assessment. As in all assessments, information is taken in, digested and then MUST be confirmed, denied and/or at the very least, folded into a functional and clinically relevant assessment of the client before the findings are accepted, dismissed and acted upon. As we always say, a gait analysis or static pedograph-type assessment (standing force plate) is never enough to make decisions on treatment to resolve problems and injuries. What is seen and represented on either are the client’s strategies around clinical problems or compensations.  Today’s photo and blog post are an exercise in critical clinical thinking to get the juices flowing and to get the observer thinking about the client’s presentation and to help open up the field to questions the observer should be entertaining.  The big questions should be, “why do i see this, what could be causing these observances ?”right foot supinated ? or more rear and lateral foot……avoiding pronation ?

READY

The Gait Guys Case of the week: What do you see?

This individual presents with Right achilles tendonitis, bilateral foot pain and a history of plantar fascitis. What do you think?

Take a look at his foot type, particularly the forefoot to rearfoot orientation. Hmmm….Asymmetrical. Notice the dropped 1^st metatarsal on the left that is not present on the right. He has a forefoot valgus on the left with a quasi flexible 1^st ray (1^st ray = medial cuneiform, 1^st metatarsal and associated phalanges) which is dropped and an uncompensated forefoot valgus on the right, with an inflexible 1^st ray.

He has bilateral external tibial torsion (which you cannot see in these pictures) right greater than left (OK, you can see that), as well as a Left anatomically short leg (tibial) of approximately 7mm.

Now look at the pedographs. BIG difference from left to right. Good tripod on right with clear markings over the calcaneus, the head of 5^th metetarsal and the head of 1^st metatarsals.  But I thought you said he had an UNCOMPENSATED forefoot valgus ?  Look at the shape of the forefoot print. It is very different from right to left. Remember, with a forefoot valgus, the medial side of the foot hits the ground before the lateral side most of the time,

How about the left? Look at all that metatarsal pressure. Looks like a loss of ankle rocker. Think that might be causing some of that left sided foot pain? Notice the print under the 1^st metatarsal is even greater; and look at all that printing of the 5^th metatarsal head. Remember, this is the shorter leg side, so this foot will have a tendency to supinate more, thus he increased pressures laterally.

Achilles tendonitis?  Stand on one leg on your foot tripod and rock between the head of your 1^st metatrsal and head of the 5^th.  Where do you feel the strain? The gastroc/soleus and peroneals. Now put all your weight on the lead of the 1^st metatarsal. What do you notice? The foot is everted. What everts the foot? The peroneals. So, if the foot is everted (like in the forefoot valgus), what muscle is left to shoulder the load? Remember also, that the gatroc/soleus group contracts from mid to late stance phase to invert the heel and assist with supination of the foot.

The Gait Guys. Your guiding light to gait literacy and competency.

Want to know more about pedographs? Get a copy of our book here.

All material copyright 2012 The Gait Guys/The Homunculus Group.