Podcast #99: How foot placement, the glutes and cross over gait all come together and make sense.

Topics: Plus, How foot placement, the glutes and cross over gait all come together and make sense. Plus, discussions on vibration,proprioception, cerebellum and movement.

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A. Link to our server: http://traffic.libsyn.com/thegaitguys/pod_99final.mp3

Podcast Direct Download: http://thegaitguys.libsyn.com/podcast-99-how-foot-placement-the-glutes-and-cross-over-gait-all-come-together-and-make-sense

Other Gait Guys stuff

B. iTunes link:
https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138
C. Gait Guys online /download store (National Shoe Fit Certification & more !)
http://store.payloadz.com/results/results.aspx?m=80204
D. other web based Gait Guys lectures:
Monthly lectures at : www.onlinece.com type in Dr. Waerlop or Dr. Allen, ”Biomechanics”

-Our Book: Pedographs and Gait Analysis and Clinical Case Studies
Electronic copies available here:

-Amazon/Kindle:
http://www.amazon.com/Pedographs-Gait-Analysis-Clinical-Studies-ebook/dp/B00AC18M3E

-Barnes and Noble / Nook Reader:
http://www.barnesandnoble.com/w/pedographs-and-gait-analysis-ivo-waerlop-and-shawn-allen/1112754833?ean=9781466953895

https://itunes.apple.com/us/book/pedographs-and-gait-analysis/id554516085?mt=11

-Hardcopy available from our publisher:
http://bookstore.trafford.com/Products/SKU-000155825/Pedographs-and-Gait-Analysis.aspx

Show notes:

Evaluating the Differential Electrophysiological Effects of the Focal Vibrator on the Tendon and Muscle Belly in Healthy People ARTICLE in ANNALS OF REHABILITATION MEDICINE · AUGUST 2014 DOI: 10.5535/arm.2014.38.4.494 · Source: PubMed

J Neurophysiol. 2014 Jul 15;112(2):374-83. doi: 10.1152/jn.00138.2014. Epub 2014 Apr 30. A neuromechanical strategy for mediolateral foot placement in walking humans.  Rankin BL

J Neurophysiol. 2015 Oct;114(4):2220-9. doi: 10.1152/jn.00551.2015. Epub 2015 Aug 19.

Hip proprioceptive feedback influences the control of mediolateral stability during human walking.

Roden-Reynolds DC1, Walker MH1, Wasserman CR1, Dean JC2.

Eur Spine J. 2015 May 26. [Epub ahead of print]
Prevalence of gluteus medius weakness in people with chronic low back pain compared to healthy controls.
Cooper NA1, Scavo KM, Strickland KJ, Tipayamongkol N, Nicholson JD, Bewyer DC, Sluka KA.

Prog Brain Res. 2004;143:353-66. Role of the cerebellum in the control and adaptation of gait in health and disease. Thach WT1, Bastian AJ.

You’d have to be smart to walk this lazy, and people are

Research suggests that humans are wired for laziness

http://www.sciencedaily.com/releases/2015/09/150910131451.htm#.VfWquNKaf3s.facebook

Jessica C. Selinger, Shawn M. O’Connor, Jeremy D. Wong, J. Maxwell Donelan. Humans Can Continuously Optimize Energetic Cost during Walking. Current Biology, 2015; DOI: 10.1016/j.cub.2015.08.016

The “Dodgy Foot”, a UK runner’s dilemma.

We get “help me” emails from all over the world on a regular basis. Recently we received this photo from a runner in Oxford, UK,  The runner was frustrated, explaining a “dodgy foot”.  We like the word. 

dodg·y    däjē/

-dishonest or unreliable; potentially dangerous; of low quality.

We can guarantee you that the solution here to this runner’s form issue is not wholly at the foot which appears “in toed” and slanted and appears ready to kick the back of the right heel, not to mention the knees that are about to brush together.  Thus, merely working on their foot strike would be so remedial and corrupt that it would a crime. 

Ivo and I do not take on cases via the internet because we cannot give all the information because we cannot examine the client, many do offer such services but people are not being given the whole story and we pledged long ago not to be part of the problem.  Anyone who recommends exercises from things they see on a video gait analysis are basically doing the same disservice in our opinion. But sometimes, as in this case, their inquiry is simple, there is a photo or video and it allows us to highlight an important component of an individuals gait which can lead them on a road to appropriate discovery. This is one of those cases.  I will not be presenting a solution, because I do not have the examination information I need, but I will propose a solid thought process that further investigation may afford progress towards resolution.

This is a non-pathologic cross over gait in my mind until proven otherwise, there may be other sources, causes and components, but when it quacks like a duck you’d be silly not to check for webbed feet. This runner even confirmed upon questioning that the left foot scuffs the inside of the right ankle/shin often, both sides scuff in fact but more left shoe on right shin. No Einsteinian epiphany there. 

  • This means a narrow swing through  (adducting) left limb. 
  • This means stance and swing phase gluteus medius communication problems. 
  • This means swing leg foot targeting problems. 
  • This often suggests right, but sometimes both right and left, frontal plane pelvis sway problems which means pelvis control is challenged which means core lumbar stability control is challenged. 
  • This means adaptive arm swing changes from the clean norm.  
  • This does NOT mean this runner has pain, or pain yet, or maybe never will have pain but there are many determinants of that which I will discuss below. 

But, make no mistake, this is flawed gait mechanics. The left swing leg is clearly targeting a more medial placement, meaning limb adduction (active or passive or both is to be determined) and this is a product of the cross over gait (unfamiliar with the cross over gait ? SEARCH our blog for the term, you will need a few hours of free time to get through it all).  Some would call the cross over gait a lazy gait, but I would rather term it an efficient gait taken too far that it has now become a liability, a liability in which they can no longer stabilize frontal plane sway/drift. A wider gait on the other hand, as in most sprinters, is less efficient but may procure more power and the wider base is more stable affording less frontal plane drift. Just go walk around your home and move from a very narrow line walking gait to a wide gait and you will feel a more powerful engagement of the glutes. Mind you, this is not a fix for cross over gaits, gosh, if it was only that simple !

This runner must investigate whether there is right frontal plane drift, and if it is in fact occurring, find the source of the drift.  It can come from many places on either limb. (This client says they are scuffing both inside ankles, which is not atypical and so we likely have drift on both right and left). We have discussed many of them here in various places on the blog over the years. Now as for “Why” the foot looks in toed, well that can also come from many places. Quite simply the adducted limb once it leaves toe off can look like this. But, perhaps it is also a product of insufficient external rotation maintenance occurred during that left stance phase, affording more internal rotation which is being unchecked and observed here during early swing.  Remember though, if this is in fact a cross over gait result, in this gait the limb approaches the ground unstacked (foot is too far inside a left hip joint plumb line) the foot will greet the ground at a far lateral strike and in supination.  Pronation will thus be magnified and accelerated, if there is enough time before toe off. However, and you can try this on your own by walking around your home, put yourself in terminal stance at toe off. Make sure you have the foot inverted so you are toeing off the lateral toes (low gear toe off). Does this foot not look like the one in the photo ? Yes it does, now just lift the foot off the ground and you have reproduced this photo. And when combined with a right pelvis drift, the foot will sneak further medially appearing postured behind the right foot. 

Keep this in mind as well, final pronation and efficient hallux (big toe) toe off does often not occur in someone who strikes the ground on a far lateral foot. I am sure this runner will now be aware of how poorly they toe off of the big toe, the hallux.  They will tend to progress towards low gear toe off, off the lesser toes. This leaves the foot inverted and this is what you are seeing in her the photo above. That is a foot that is inverted and supinated and it carried through all the way through toe off and into early swing. It is a frequently component of the cross over gait, look for it, you will find it, often. 

Final thoughts, certainly this can be an isolated left swing phase gluteus medius weakness enabling an adducted swing limb thus procuring a faulty medial foot placement, but it is still part of the cross over phenomenon.  Most things when it comes to a linked human frame do not work in isolation.  But i will leave you with a complicating factor and hopefully you will realize that gait analysis truly does require a physical exam, and without it you could be missing the big picture problem.  What if she has a notable fixed anatomic internal tibia torsion on that left side. Yup, it could all be that simple, and that is not something you can fix, you learn to manage that one as a runner.  

* Side bar rant: Look at any google search of runners photos and you will see this type of swing limb foot posturing often, far too often.  And yes, you can take the stance that “I do it as well and i have no injuries or problems so what is the big deal?”.  Our response is often “you do have an issue, it may be anatomic or functional, but you do have an asymmetrical gait and you think it is not a problem, YET”. And maybe you will run till you are 6 feet under and not have a problem because you have accomodated over many years and you are a great compensator, yes, some people get lucky. Some people also do not run enough miles that these issues express themselves clinically so lets be fair. But some of these people are reality deniers and spend their life buying the newest brace or gadget, trying a different shoe insert, orthotic or new shoe of the month and shop over and over again for another video gait analysis expert who can actually fix their pain or problem. And then there are those who have a 45 minute home exercise program that they need to do to keep their problems at bay, managing, not fixing anything.  Or, they spend an hour a week on the web reading article after article on what are the top 4 exercises for iliotibial band syndrome for example. They shop for the newest Graston practitioner, the newest kinesio taping pattern, Voodoo bands, breathing patterns, compression socks etc.  And sometimes they are the ones that say they still dont have a problem.You get the drift.  Gosh darn it, find someone who knows what the hell they are doing and can help you fix the issues that are causing the problem.  And yes, some of the above accoutrements may be assistive in that journey. 

I have dealt with this unique toe off issue way too many times not to roll my eyes at it any longer. It is to the point that it is an automated evaluation and solution program that begins to run in my head. Once you see something enough times, you learn all of the variations and subtle nuiances that a problem can take on. But, trying to fit everyone into a similar solution model is where the novice coach, trainer or clinician will get into trouble. Trust us, it all starts with an examination, a true clinical physical examination.  If one leaves the investigatory process to a series of screens or functional movement patterns, “activation” attempts, digital gait analysis or strength tests one is juggling chainsaws and the outcome you want is often not likely to occur. There is nothing wrong with making these components part of the investigation process, but on their own, they are not enough to get the honest answer many times.  Of course, Ivo and i were not able to jump the pond and examine this runner with our own eyes and hands so today’s dialogue was merely to offer this runner some food for thought to open their mind to our thought process, in the hopes that they can find someone to help them solve the underlying problem and not merely make the gait look cleaner. Making someone’s walking or running gait look cleaner is not hard, but making it subconsciously competent and clean (without thought or effort) requires a fix to the underlying problem. We can ALMOST guarantee you that the solution here to this runner’s form issue is not wholly at the foot that looks in toed and slanted. Merely working on their foot strike would be so remedial and corrupt that it would a crime.

Dr. Shawn Allen, one of the gait guys

Psoas, iliacus. . . .  hip flexors ?

How many times have you heard us say, “hip flexion in the swing phase of gait is not driven by the hip flexors. In swing phase, the psoas and iliacus complex is not a hip flexor initiator, it is a hip flexion perpetuator/” ?
More evidence … . .
“These experiments also showed that the trailing leg is brought forward during the swing phase without activity in the flexor muscles about the hip joint. This was verified by the absence of EMG activity in the iliacus muscle measured by intramuscular wire electrodes. Instead the strong ligaments restricting hip joint extension are stretched during the first half of the swing phase thereby storing elastic energy, which is released during the last half of the stance phase and accelerating the leg into the swing phase. This is considered an important energy conserving feature of human walking. ”

http://www.ncbi.nlm.nih.gov/pubmed/24814597

Foot Clearance: We don’t think about it until we are face down in the mud, and we have all been there.

How many times have you tripped over something so small and insignificant you can barely believe it ? We have all tripped over a small elevation in a cracked sidewalk or a curled up rug corner.  But sometimes we look back and there is no evidence of a culprit, not even a Hobbit or an elf.  How can this happen ?
Minimum foot clearance (MFC) is defined as the minimum vertical distance between the lowest point of the foot of the swing leg and the walking surface during the swing phase of the gait cycle. In other simpler words, the minimum height all parts of the foot need to clear the ground to progress through the swing phase of the limb without contacting the ground. One could justify that getting as close to this minimal amount without catching the foot is most mechanically advantageous.  But, how close to vulnerability are you willing to get ? And as you age, do you even want to enter the danger zone ? Obviously, insufficient clearance is linked to tripping and falling, which is most concerning in the elderly. 
Trips or falls from insufficient foot clearance can be related to insufficient hallux and toe(s) dorsiflexion (extension), ankle dorsiflexion, knee flexion and/or hip flexion, failure to maintain ipsilateral pelvis neutral ( anterior/posterior pelvis posture shifting), even insufficient hip hike generated by the contralateral hip abductors, namely the gluteus medius in most people’s minds. It can also be from an obvious failed concerted effort of all of the above. Note that some of these biomechanical events are sagittal and some are frontal plane.  However, do not ever forget that the swing leg is moving through the axial plane, supported in part by the abdominal wall, starting from a posteriorly obliqued pelvis at swing initiation into an anteriorly obliqued position at terminal swing. We would be remiss as well if we did not ask the reader to consider the “inverted pendulum theory” effect of controlling the dynamically moving torso over the fixed stance phase leg (yes, we could have said “core stability” but that is so flippantly used these days that many lose appreciation for really what is happening dynamically in human locomotion).  If each component is even slightly insufficient, a summation can lead to failed foot clearance.  This is why a total body examination is necessary, every time, and its why the exclusive use of video gait analysis alone will fail every time in finding the culprit(s). 
When we examine people we all tend to look for biomechanical issues unless one grasps the greater global picture of how the body must work as a whole. When one trips we first tend to look for an external source as the cause such as a turned up rug or an object, but there are plentiful internal causes as well. For example, we have this blog post on people tripping on subway stairs.  In this case, there was a change in the perceptual height of the stairs because of a subconscious, learned and engaged sensory-motor behavior of prior steps upward.  However, do not discount direct, peripheral and lower fields of view vision changes or challenges when it comes to trips and falls. Do not forget to consider vestibular components, illumination and gait speed variables as well.  Even the most subtle change in the environment (transitions from tile to carpet, transitions from treadmill to ground walking etc) can cause a trip or fall if it is subtle enough to avoid detection, especially if one is skirting the edge of MFC (minimal foot clearance) already. And, remember this, gait has components of both anticipatory and reactive adjustments, any sensory-motor adaptive changes that impair the speed, calculation and timely integration of these adjustments can change gait behaviors. Sometimes even perceived fall or trip risk in a client can easily slip them into a shorter step/stride length to encourage less single leg stance phase and more double support phase gait. This occurs often in the elderly. This can be met with a reduced minimal foot clearance by design which in itself can increase risk, especially at the moment of transition from a larger step length to a shorter one. Understanding all age-related and non-age related effects on lower limb trajectory variables as described above and only help the clinician become more competent in gait analysis of your client and in understanding the critical variables that are challenging them. 
Many studies indicate that variability and consistency in a motor pattern such as those necessary for foot clearance are huge keys for predictable patterns and injury prevention, and in this case a predictor for trips and falls.  Barrett’s study concluded that “greater MFC variability was observed in older compared to younger adults and older fallers compared to older non-fallers in the majority of studies. Greater MFC variability may contribute to increased risk of trips and associated falls in older compared to young adults and older fallers compared to older non-fallers.”
Once again we outline our mission, to enlighten everyone into the complexities of gait and how gait is all encompassing.  There are so many variables to gait, many of which will never be noted, detected or reflected on a gait analysis and a camera.  Don’t be a minimalist when it comes to evaluating your client’s gait, simply using a treadmill, a camera and some elaborate computer software are not often going to cut the mustard when it really counts.  A knowledgeable and engaged brain are arguably your best gait analysis tools.  
Remember, what you see in someone’s gait is not their problem, it is their adaptive strategy(s).  That is all you are seeing on your camera and computer screen, compensations, not the source of the problem(s).
Shawn and Ivo
the gait guys
References (some of them): 

1. Gait Posture. 2010 Oct;32(4):429-35. doi: 10.1016/j.gaitpost.2010.07.010. Epub 2010 Aug 7.

A systematic review of the effect of ageing and falls history on minimum foot clearance characteristics during level walking. Barrett RS1, Mills PM, Begg RK.

2. Gait Posture. 2007 Feb;25(2):191-8. Epub 2006 May 4. Minimum foot clearance during walking: strategies for the minimisation of trip-related falls. Begg R1, Best R, Dell’Oro L, Taylor S.

3. Clin Biomech (Bristol, Avon). 2011 Nov;26(9):962-8. doi: 10.1016/j.clinbiomech.2011.05.013. Epub 2011 Jun 29. Ageing and limb dominance effects on foot-ground clearance during treadmill and overground walking. Nagano H1, Begg RK, Sparrow WA, Taylor S.

4. Acta Bioeng Biomech. 2014;16(1):3-9. Differences in gait pattern between the elderly and the young during level walking under low illumination. Choi JS, Kang DW, Shin YH, Tack GR.

Lebron James and his funky toes. We have the scoop as to what is going on.

http://bleacherreport.com/articles/1757693-everybody-look-at-lebron-james-toesimage

This is what happens when you get too much short extensor tone and/or strength in the digits of the foot.  Now this is his trailing foot and he has moved into toe off so he should be activating his toe extensors and the tibialis anterior (ie. the anterior compartment) to create clearance for that foot so that he doesn’t catch the toes on the swing through phase of gait.  In this case we do not see alot of ankle dorsiflexion (which we should see at this point) so we are  seeing a compensation of perhaps increased short extensor (of the toes) activity.  

We also see what appears to be a drifting of the big toe (the hallux) underneath the 2nd toe. This often happens when a bunion or hallux valgus is present.  Now we do not see a bunion present here but the viewing angle is not optimal however it does appear that there is a slight drift of the hallux big toe towards the lesser toes . We are not sure if we would qualify this as hallux valgus, and if so it is mild, but none the less we see a slight lateral drift. What is interesting is that despite the obvious activity of the lesser toes short extensor muscle (EDB) we do not see a simultaneous activity of the short extensor of the hallux (EHB, extensor hallucis brevis). Does he need to do our exercise ? See video link here ! 

And so, when the lesser toes are in extension as we see here and the big toe is not moving into extension, and when that is simultaneously combined with even a little hallux valgus tendency, the big toe will drift underneath the lesser toes as we see here, even appearing to push the 2nd toe further into extension.  

As for his little toe, well, Dr. Allen  has one just like it so perhaps he missed his calling in the NBA. Some folks just do not have as plantarward orientation of the 5th toe and so it migrates upward (dorsally) a little. This can be from birth but it can also come from trauma. But in time because the toe is not more plantar oriented, the dorsal muscles (the extensors) become more dominant and the toe just starts to take on this kind of appearance and orientation. It will reduce significantly when the foot is on the ground and the extensors are turned off, but it looks more shocking during the swing phase because of the extensor dominance in that phase.

This kind of presentation if left unchecked can lead to hammer toes, plantar fat pad migration distally exposing the metatarsal heads to more plantar forces without protection and a host of other problems.  Lebron needs to do our Shuffle Walk Exercise to get more ankle rocker (dorsiflexion) and also work to increase his long toe extensors (EDL) and lumbricals.  This will flatten his toes and improve mechanical leverage.  Remember, if you gait better foot function with increased ankle dorsiflexion you will get more hip extension and more glute function.  But does the big fella really need to jump any higher? We are sure he would accept being faster though … .  who wouldn’t ?

Fee for today’s long distance consult: …  Lebron, lets say 10,000$ and we will call it even.  Sound good ?  But a lifetime of prettier, stronger and more functional toes……priceless. Have  your people contact our people.  (Ok, we don’t have people, but we do have an email address here on our blog !).

Shawn and Ivo, The Gait Guys.  Even helping the elite, little by little.

Lebron James and his funky toes. We have the scoop as to what is going on.

http://bleacherreport.com/articles/1757693-everybody-look-at-lebron-james-toesimage

This is what happens when you get too much short extensor tone and/or strength in the digits of the foot.  Now this is his trailing foot and he has moved into toe off so he should be activating his toe extensors and the tibialis anterior (ie. the anterior compartment) to create clearance for that foot so that he doesn’t catch the toes on the swing through phase of gait.  In this case we do not see alot of ankle dorsiflexion (which we should see at this point) so we are  seeing a compensation of perhaps increased short extensor (of the toes) activity.  

We also see what appears to be a drifting of the big toe (the hallux) underneath the 2nd toe. This often happens when a bunion or hallux valgus is present.  Now we do not see a bunion present here but the viewing angle is not optimal however it does appear that there is a slight drift of the hallux big toe towards the lesser toes . We are not sure if we would qualify this as hallux valgus, and if so it is mild, but none the less we see a slight lateral drift. What is interesting is that despite the obvious activity of the lesser toes short extensor muscle (EDB) we do not see a simultaneous activity of the short extensor of the hallux (EHB, extensor hallucis brevis). Does he need to do our exercise ? See video link here ! 

And so, when the lesser toes are in extension as we see here and the big toe is not moving into extension, and when that is simultaneously combined with even a little hallux valgus tendency, the big toe will drift underneath the lesser toes as we see here, even appearing to push the 2nd toe further into extension.  

As for his little toe, well, Dr. Allen  has one just like it so perhaps he missed his calling in the NBA. Some folks just do not have as plantarward orientation of the 5th toe and so it migrates upward (dorsally) a little. This can be from birth but it can also come from trauma. But in time because the toe is not more plantar oriented, the dorsal muscles (the extensors) become more dominant and the toe just starts to take on this kind of appearance and orientation. It will reduce significantly when the foot is on the ground and the extensors are turned off, but it looks more shocking during the swing phase because of the extensor dominance in that phase.

This kind of presentation if left unchecked can lead to hammer toes, plantar fat pad migration distally exposing the metatarsal heads to more plantar forces without protection and a host of other problems.  Lebron needs to do our Shuffle Walk Exercise to get more ankle rocker (dorsiflexion) and also work to increase his long toe extensors (EDL) and lumbricals.  This will flatten his toes and improve mechanical leverage.  Remember, if you gait better foot function with increased ankle dorsiflexion you will get more hip extension and more glute function.  But does the big fella really need to jump any higher? We are sure he would accept being faster though … .  who wouldn’t ?

Fee for today’s long distance consult: …  Lebron, lets say 10,000$ and we will call it even.  Sound good ?  But a lifetime of prettier, stronger and more functional toes……priceless. Have  your people contact our people.  (Ok, we don’t have people, but we do have an email address here on our blog !).

Shawn and Ivo, The Gait Guys.  Even helping the elite, little by little.