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Notice the differences in running (top) vs sprinting (bottom) activation patterns?

This picture (along with the MIchaud muscular firing pattern ones) are becoming some of my favorite ones to talk about. I just stare at them and look for differences and similarities. 

Check out that the abs do not seem to fire in running (in this study at least), but do in sprinting. Note also that most muscles fire longer (and we wil assume harder) during sprinting. Also check out the peroneals, which fire just as the foot touches down in sprinting, probably to make up for the instrinsics not firing, and assist in creating a rigid lever for push off. 



from: Mann et al 1986

Podcast 97: Decomposition of human movement.

Topics: Decomposition of movement, sacrificing speed and efficiency for movement, gait efficiency, arm swing, more on injuries and unshod running and more !

A. Link to our server: http://traffic.libsyn.com/thegaitguys/pod_97final.mp3

Podcast Direct Download:  http://thegaitguys.libsyn.com/podcast-97

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:

-Brain Friendly Interface Could Change the Way People with Spinal Cord Injuries Lead Their Lives
http://neurosciencenews.com/extracellular-matrix-brain-interface-2395/

-Barefoot vs Shoe debate
http://www.theglobeandmail.com/life/health-and-fitness/fitness/barefoot-vs-shod-running-its-a-dead-heat/article26180292/

-Sacrificing speed and efficiency for stability as we age (1) . Not a bad plan. Kind of like what we spoke about here below in this video: returning to a more primitive state as the system starts to break down.

1. Zurales K, DeMott TK, Kim H, et al. Gait efficiency on an uneven surface is associated with falls and injury in older subjects with a spectrum of lower limb neuromuscular function: A

prospective study. Am J Phys Med Rehabil 2015 Jun 5. [Epub ahead of print]

https://www.youtube.com/watch?v=_fBjyutWQvU  video link to our video on this

-http://lermagazine.com/news/in-the-moment-gait/speed-trap-slowest-seniors-have-increased-mortality

-Shoe:  the UnderArmor Fat Tire GTX Trail shoe.

https://www.underarmour.com/…/mens-ua-fat-tire-g…/pid1262064

- assessing the different genders: http://www.ncbi.nlm.nih.gov/pubmed/12689785

Ferber R, Davis IM, Williams DS 3rd. Gender differences in lower extremity mechanics during running. Clin Biomech 2003;18(4):350-357.

-Arm Swing
http://thegaitguys.tumblr.com/post/128715659449/unique-adaptations-to-arm-swing-challenges-the

Medial or lateral foot placement ?

Foot placement matters. We have repeatedly beaten this topic in our dialogues on “the cross over gait” for years now.
Lack of Stability often, if perhaps not always, limits mobility.
Mediolateral stability can be efficiently controlled through appropriate foot placement. This study hypothesized that humans control mediolateral foot placement through swing leg muscle activity, basing this control on the mechanical state of the contralateral stance leg. Thus, obviously, if thestance phase limb has sensory-motor deficiencies, which might be easily translated into “balance” or control issues in single leg stance evaluation, this will impact the swing leg and thus subsequent foot placement.
In this study, “During Unperturbed walking, greater swing-phase gluteus medius (GM) activity was associated with more lateral foot placement.”
“The Perturbed walking results indicated a causal relationship between stance leg mechanics and swing-phase GM activity. Perturbations that reduced the mediolateral CoM displacement from the stance foot caused reductions in swing-phase GM activity and more medial foot placement." 

The swing leg is taking cues from the stance leg mechanics. If stance phase has challenges, the swing limb will be forced to accommodate and adapt, and that means altered foot placement.  

Once again, remember, (broken record moment)……. "what you see is not your client’s problem, it is their strategy to get around/compensate for the problem”. Don’t you dare correct your client’s foot placement without examining why they are doing what they are doing. Get to the root of the problem you are “seeing”.

-Dr. Shawn Allen


http://www.ncbi.nlm.nih.gov/pubmed/24790168

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 BL1, Buffo SK1, Dean JC2.

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A cause of ishial pain?

How many of us treat runners on a regular basis? Most of us I would say. While lecturing, I had an epiphany about recalcitrant hamstring insertional pain, that does seem to respond to conventional therapy. Take a look at the trigger point referral pattern for the semimembranosis/ semitendonosis. Note that in closed chain, these are external rotators of the thigh. Thinking about this, they would eccentrically contract (theoretically) to decelerate internal rotation of the thigh (such as with excessive midfoot pronation at initial contact and loading response.

Now look at when these guys fire during running gait. The left side of the graph (up to TO)  represents the stance phase of running gait (Mann 1986). The right side represents swing (or float) phase. Note that the medial hamstrings should fire from about foot descent to mid support (or midstance), with a little blast after the foot leaves the ground (asumed eccentrically) to assist in slowing the leg.

Now think about if the foot is a poor lever and remains on the ground just a little longer and rotates medially a little too far (overpronation); this muscle could conceivably be over worked and result in the trigger point referral pattern seen above on the ishial tuberosity.

Ah, but how to fix it? 

We could dry needle it and rehab it (better train it eccentrically, since that is how it is working), but it is already overworked, and in my cllinical experience, only provides temporary relief of the symptom. What other muscles seen in the chart could help? Hmmm… Take a look at the tibialis anterior (dorsiflexor/inverter), gastroc (medial) (plantarflexor/inverter), foot intrinsics and glute max/ posterior fibers of the glute medius. All external rotators (save for the foot intrinsics, which should fire from midstance to toe off) and a bonus pronatory decelerator for the tibialis anterior and able to slow an excessively internally rotating lower leg. You better check and make sure they are all on line before just treating the area of the chief complaint!

The Gait Guys. Keeping it real and giving you the tools to do a better job at what we all love to do : ) .

Taking advantage of the stretch reflex and reciprocal inhibition; or the “reverse stretch”Reciprocal inhibition is a topic we have spoken about before on the blog (see here). The diagram above sums it up nicely. Note the direct connection from the s…

Taking advantage of the stretch reflex and reciprocal inhibition; or the “reverse stretch”

Reciprocal inhibition is a topic we have spoken about before on the blog (see here). The diagram above sums it up nicely. Note the direct connection from the spindle to the alpha motor neuron, which is via a Ia afferent fiber.  When the spindle is stretched, and the pathway is intact, the uscle will contract. What kind of stimulus affects the spindle? A simple “stretch” is all it takes. Remember spindles respond to changes in length. So what happens when you do a nice, slow stretch? You activate the spindle, which activates the alpha motor neuron. If you stretch long enough, you may fatigue the reflex. So why do we give folks long, slow stretches to perform? Certainly not to “relax” the muscle!

How can we “use” this reflex? How about to activate a weak or lengthened muscle? Good call.

Did you notice the other neuron in the picture? There is an axon collateral coming off the Ia afferent that goes to an inhibitory interneuron, which, in turn, inhibits the antagonist of what you just stretched or activated. So if you acitvate one muscle, you inhibit its antagonist, provided there are not too many other things acting on that inhibitory interneuron that may be inhibiting its activity. Yes, you can inhibit something that inhibits, which means you would essentially be exciting it. This is probably one of the many mechanisms that explain spasticity/hypertonicity

How can we use this? How about to inhibit a hypertonic muscle?

Lets take a common example: You have hypertonic hip flexors. You are reciprocally inhibiting your glute max. You stretch the hypertonic hip flexors, they become more hypertonic (but it feels so good, doesn’t it?) and subsequently inhibit the glute max more. Hmm. Not the clinical result you were hoping for?

How about this: you apply slow stretch to the glutes (ie “reverse stretch”) and apply pressure to the perimeter, both of which activate the spindle and make the glutes contract more. This causes the reciprocal inhibition of the hip flexors. Cool, eh? Now lightly contract the glutes while you are applying a slow stretch to them; even MORE slow stretch; even MORE activation. Double cool, eh?

Try this on yourself. Now go try it on your clients and patients. Teach others. Spread the word.

A great, FREE, full text on forward and backward walking kinematics and a possible link to central pattern generators. “Leg kinematics during backward walking (BW) are very similar to the time-reversed kinematics during forward walking (FW). T…

A great, FREE, full text on forward and backward walking kinematics and a possible link to central pattern generators.

“Leg kinematics during backward walking (BW) are very similar to the time-reversed kinematics during forward walking (FW). This suggests that the underlying muscle activation pattern could originate from a simple time reversal, as well…

"We concluded that the changes in muscle contributions imply that a simple time reversal would be insufficient to produce BW from FW. We therefore propose that BW utilizes extra elements, presumably supraspinal, in addition to a common spinal drive. These additions are needed for propulsion and require a partial reconfiguration of lower level common networks.”

http://jn.physiology.org/content/107/12/3385


Similar muscles contribute to horizontal and vertical acceleration of center of mass in forward and backward walking: implications for neural controlKaren Jansen, Friedl De Groote, Firas Massaad, Pieter Meyns, Jacques Duysens, Ilse JonkersJournal of Neurophysiology Published 15 June 2012 Vol. 107 no. 12, 3385-3396 DOI: 10.1152/jn.01156.2011

Gait and Climbing: Part 1

Lucid Dreaming is the name of a rock in the Buttermilks of Bishop, California. This is no ordinary rock. It is a V15. Summiting this rock is basically only 3 moves off of 3 holds, from your fingertips. The remainder of the climb is sliced bread. If you can do the 3, you can get to the top. The problem is, only a handful of people in the world can do it. How hard can this be, after all you start sitting down.

Strength, stability, mobility, endurance, skill, experience, movement patterns … . it is all here, today, on The Gait Guys blog.

Author: Dr. Shawn Allen

There are things that other people can do in life that rattle your brain. These are tasks that these individuals make look fairly simple, but in actuality are nearly impossible to the average person.  The honest fact is that many of us could do many of these things to a degree if we would dedicate a portion of our day to building the engine to perform these tasks, but the truth is that many of us would rather sit down and be entertained than get up and struggle.

Here on The Gait Guys blog, bipedal and quadrupedal gait has been discussed for over 5 years. Discussions have gone deep into the strange quadrupedal gait of Uner Tan Syndrome and have delved into the critical neurology behind CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs. We have gone on and on about arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during walking running gaits.

Today I will look briefly at the interconnected arm and leg function in a high functioning human arguably one of the best new hot shots in climbing, Alex Megos. This year the German, as seen in this video link today, managed to summit Lucid Dreaming, a V15 in the Buttermilks of Bishop, California. Hell, you can say that this is just a big boulder, but there are not many V15s in the world like this one. Only a few of the very best in the world have even tried this rock, and you can count even fewer who have reached the summit. So, what does V15 mean to you? “virtually impossible” just about sums it up. Watch the video, this V15 starts from a “sit-start”, many folks wouldn’t even get their butts off the ground to complete the first move, that is how hard this is.  Watch the video, if this does not cramp your brain, you perhaps you don’t have one.

Are there possible neurologic differences in climbers such as Megos as compared to other quadruped species?  Primarily, there is suspect of an existing shift in the central pattern generators because of the extraordinary demand on pseudo-quadrupedal gait of climbing because of the demand on the upper limbs and their motorneuron pools to mobilize the organism up the mountain. We know these quadrupedal circuits exist. In 2005 Shapiro and Raichien wrote “the present work showed that human QL(quadrupedal locomotion) may spontaneously occur in humans with an unimpaired brain, probably using the ancestral locomotor networks for the diagonal sequence preserved for about the last 400 million years.”

As we all know, the interlimb coordination in climbing and crawling biomechanics shares similar features to other quadrupeds, both primate and non-primate, because of similarities in our central pattern generators (CPG’s). New research has however determined that the spaciotemportal patterns of spinal cord activity that helps to mediate and coordinate arm and leg function both centrally, and on a cord mediated level, significantly differ between the quadruped and bipedal gaits. In correlation to climbers such as Megos however, we need to keep in mind that the quadrupedal demands of a climber (vertical) vastly differ in some respects to those of a non-vertical quadrupedal gait such as in primates, in those with Uner Tan Syndrome and during our “bear crawl” challenges in our gyms. This should be obvious to the observer in the difference in quadrupedal “push-pull” that a climber uses and the center-of-mass (COM) differences.  To be more specific, a climber must reduce fall risk by attempting to keep the COM within the 4 limbs while remaining close to the same surface plane as the hands and feet (mountain) while a primate,  human or Uner Tan person will choose  to “tent up” the pelvis and spine from the surface of contact which narrows the spreading of the 4 contact points. Naturally, this “tenting up” can be reduced, but the exercise becomes infinitely more difficult, to the point that most cannot quadrupedally ambulate more than a very short distance. I will discuss this concept in Part 2 of this series on climbing.  If you study childhood development and crawling patterns, you need to be familiar with UTS (search our blog, save yourself the time), the flaws in the neurology behind the "Bird Dog” rehab pattern, and crawling mechanics … and of course, study climbers.

Some research has determined is that in quadrupeds the lower limbs displayed reduced orientation yet increased ranges of kinematic coordination in alternative patterns such as diagonal and lateral coordination.  This was clearly different to the typical kinematics that are employed in upright bipedal locomotion. Furthermore, in skilled mountain climbers, these lateral and diagonal patterns are clearly more developed than in study controls largely due to repeated challenges and subsequent adaptive changes to these lateral and diagonal patterns.  What this seems to suggest is that there is a different demand and tax on the CPG’s and cord mediated neuromechanics moving from bipedal to quadrupedal locomotion. There seemed to be both advantages and disadvantages to both locomotion styles. Moving towards a more upright bipedal style of locomotion shows an increase in the lower spine (sacral motor pool) activity because of the increased and different demands on the musculature however at the potential cost to losing some of the skills and advantages of the lateral and diagonal quadrupedal skills.  Naturally, different CPG reorganization is necessary moving towards bipedalism because of these different weight bearing demands on the lower limbs but also due to the change from weight bearing upper limbs to more mobile upper limbs free to not only optimize the speed of bipedalism but also to enable the function of carrying objects during locomotion.

The take home seems to suggest that gait retraining is necessary as is the development of proper early crawling and progressive quadruped locomotor patterns. Both will tax different motor pools within the spine and thus different central pattern generators (CPG). A orchestration of both seems to possibly offer the highest rewards and thus not only should crawling be a part of rehab and training but so should forward, lateral and diagonal pattern quadrupedal movements, on varying inclines for optimal benefits.  Certainly I need to do more work on this topic, the research is out there, but correlating the quad and bipedal is limited. I will keep you posted. Be sure to read my 3 part series on Uner Tan Syndrome, here on The Gait Guys blog. Some of today’s blog is rehash of my older writings, naturally I am setting the stage for “Part 2″ of Climbing.

- Dr. Shawn Allen

 References:

Shapiro L. J., Raichien D. A. (2005). Lateral sequence walking in infant papio cynocephalus: implications for the evolution of diagonal sequence walking in primates. Am. J. Phys. Anthropol.126, 205–213 10.1002/ajpa.20049

Scand J Med Sci Sports. 2011 Oct;21(5):688-99. Idiosyncratic control of the center of mass in expert climbers. Zampagni ML , Brigadoi SSchena FTosi PIvanenko YP

J Neurophysiol. 2012 Jan;107(1):114-25. Features of hand-foot crawling behavior in human adults. Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F.

Thoughts on the adductor grouping to ponder. I found this while prepping for the dry needling course I am teaching this weekend and thought you may enjoy it. Though the primary actions of the addcutors are well established, secondary actions (whethe…

Thoughts on the adductor grouping to ponder. 

I found this while prepping for the dry needling course I am teaching this weekend and thought you may enjoy it. Though the primary actions of the addcutors are well established, secondary actions (whether they are acually internal or external rotators) remains to be elucidated.

Here is a nice abstract that supports the dynamic function of them as external rotators (eccentrically) during gait.

“Anatomical texts agree on most muscle actions, with a notable exception being the action of the adductors of the hip in the transverse plane. Some texts list an action of the adductor brevis (AB), adductor longus (AL), and/or adductor magnus (AM) as internal rotation, whereas others list an action of external rotation. The purpose of this article is to present a functional model in support of the action of external rotation. Transverse plane motion of the femur at the hip during normal gait is driven by subtalar joint motion during the loading response, terminal stance, and preswing phases. During the loading response, the subtalar joint pronates, and the talus adducts. This talar adduction results in the lower leg, and subsequently the femur, internally rotating. During terminal stance and preswing, the opposite occurs; the subtalar joint supinates as the talus abducts in response to forces generated from the lower extremity and in the forefoot. Electromyographic (EMG) studies indicate varied activity in the AB, AL, and AM during the loading response, terminal stance, and preswing phases of the gait cycle. A careful analysis of EMG activity and kinematics during gait suggests that, in the transverse plane, the adductors may be eccentrically controlling internal rotation of the femur at the hip during the loading response, rather than the previously reported role as concentric internal rotators. In addition, these muscles may also concentrically produce external rotation of the femur at the hip during terminal stance and preswing. Physical therapists should consider this important function of the hip adductors during gait when evaluating a patient and designing an intervention program. Anatomical texts should consider listing the concentric action of external rotation of the femur at the hip as one action of the AB, AL, and AM, particularly when starting from the anatomic position.”

Leighton RD. A functional model to describe the action of the adductor muscles at the hip in the transverse plane.Physiother Theory Pract. 2006 Nov;22(5):251-62.Leighton RD. A functional model to describe the action of the adductor muscles at the hip in the transverse plane.Physiother Theory Pract. 2006 Nov;22(5):251-62.

Podcast 96: Minimalism Shoes, Toe Trauma, Meniscal Impingement.

The Minimalist Shoe Index, Pincer toe nails, toe problems, anteromeniscofemoral impingement syndrome and much more on today’s show !

A. Link to our server: http://traffic.libsyn.com/thegaitguys/pod_96f.mp3

Direct Download:  http://thegaitguys.libsyn.com/podcast-96

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:

1. New Cameras In Japan Can Detect Drunks At Train Stations
http://www.popsci.com/cameras-japan-detect-drunks-train-stations

2. It takes a lot of nerve: Scientists make cells to aid peripheral nerve repair
http://www.medicalnewstoday.com/releases/297854.php
-Scientists at the University of Newcastle, UK, have used a combination of small molecules to turn cells isolated from human skin into Schwann cells

3. The Minimalist Shoe Definition study

http://www.jfootankleres.com/content/8/1/42

A consensus definition and rating scale for minimalist shoes
Jean-Francois Esculier123, Blaise Dubois13, Clermont E. Dionne14, Jean Leblond2 andJean-Sébastien Roy12* http://www.jfootankleres.com/content/8/1/42

modified Delphi study, 42 experts from 11 countries

http://www.jfootankleres.com/content/supplementary/s13047-015-0094-5-s1.pdf

-Results

The following definition of minimalist shoes was agreed upon by 95 % of participants: “Footwear providing minimal interference with the natural movement of the foot due to its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices”. Characteristics to be included in MI were weight, flexibility, heel to toe drop, stack height and motion control/stability devices, each subscale carrying equal weighing (20 %) on final score.

4. CASE:
Ivo: broken toe, prioprioception
this: http://www.ncbi.nlm.nih.gov/pubmed/2245598
and this http://www.ncbi.nlm.nih.gov/pubmed/19955289

5. CASE: anterior meniscofemoral impingment syndrome
http://tmblr.co/ZrRYjx1d8503W

http://thegaitguys.tumblr.com/post/17713779565/anterior-knee-pain-in-a-young-marathon-hopeful

6. Pincer Toe nails:

http://thegaitguys.tumblr.com/post/127638788139/pincher-nails-who-knew-note-there-are-two–  

Does slowing gait increase gait stability ?

As this study suggests, it has been difficult to find studies that establish a clear connection between gait stability and gait speed. One can easily assume that slowing down increases stability, we do it on slippery surfaces, we do it when a joint is painful, even the elderly do it naturally everyday. Walking speed, step length, step frequency, step width, local dynamic stability , and margins of stability were measured in this study below. It was found that the subjects did not change walking speed in response to the balance perturbations rather they made shorter, faster, and wider steps with increasing perturbation intensity. They became locally less stable in response to the perturbations but increased their margins of stability in medio-lateral and backward direction. 

So what did they conclude ?  Here are their words,“In conclusion, not a lower walking speed, but a combination of decreased step length and increased step frequency and step width seems to be the strategy of choice to cope with medio-lateral balance perturbations, which increases Margins of Stability (MoS) and thus decreases the risk of falling.”

It is my assumption, and this just seems logical, that if the perturbations were to continue constantly, that one would slow the gait speed to reduce the need for these shorter, faster and wider steps. 

Dr. Shawn Allen

http://www.ncbi.nlm.nih.gov/pubmed/22464635

Gait Posture. 2012 Jun;36(2):260-4. doi: 10.1016/j.gaitpost.2012.03.005. Epub 2012 Mar 29.Speeding up or slowing down?: Gait adaptations to preserve gait stability in response to balance perturbations.Hak L1, Houdijk H, Steenbrink F, Mert A, van der Wurff P, Beek PJ, van Dieën JH.

Unique adaptations to arm swing challenges: the one armed runner.  Welcome to Luke Ericson, an amazing athlete and man.

Written By Dr. Shawn Allen

Human gait is cyclical. For the most part, when one limb is engaged on the ground (stance phase), the other is in swing phase. Before I continue, you should recall that there is a brief double limb support phase in walking gait, that which is absent in running gait. Also, I wish to remind you of our time hammered principle that when the foot is on the ground the glutes are heavily in charge, and when the foot is in the air, the abdominals are heavily in charge.  

For one to move cleanly and efficiently one would assume that the best way to do that would be to ensure that the lower 2 limbs are capable of doing the exact same things, with the same timing, same skill, same endurance and same strength. This goes for the upper 2 limbs as well, and then of course the synchronizing of the 4 in a cohesive effort. For this clean seamless motor function to occur, one must assume that there would be no injuries that had left a remnant mark on one limb thus encouraging a necessary compensation pattern in that limb (and one that would then have to be negotiated with the opposite limb as well as the contralateral upper or lower limb).  

Removing a considerable mass of tissue anywhere in the body is going to change the symmetry of the body and require compensations. One can clearly see the effects of this on this athletes body in the video above. He even eludes to the fact that he has a scoliosis, no surprise there.  There is such an unequal mass distribution that there is little way the spine had any chance to remain straight.  Not only is this going to change symmetry from a static postural perspective (bulk, weight, fascial plane changes, strength etc) but it will change dynamic postural control, mobility and stability as well as dynamic spinal kinematics.  I have talked about this previously in a blog piece I wrote on post-mastectomy clients display changes in spatiotemporal gait parameter such as step length and gait velocity.

-mastectomy post: http://tmblr.co/ZrRYjx1XB8RhO

If you have been with The Gait Guys for more than a year you will know that impairing an arm swing will show altered biomechanics in the opposite lower limb (and furthermore, if you alter one lower limb, you begin a process of altering the biomechanical function and rhythmicity of the opposite leg as well.) You can search the blog for “arm swing part 1 and part 2″ for those dialogues.

Arm swing impairment is a real issue and it is one that is typically far overlooked and misrepresented. The intrinsic effects of altering the body through subtraction of tissue are not all that dissimilar to extrinsic changes into the system from things like  walking with a handbag/briefcase, walking with a shoulder bag, walking and running with an ipod or water bottle in one hand. And do not forget other intrinsic problems that affect spinal symmetry, for example consider the changes on the system from scoliosis as in this case.  It can cycle back on its own feedback loop into the system, either consciously or unconsciously altering arm swing and thus global body kinematics.  

There is a reason that in my practice I often assess and treat contralateral upper and lower limbs as well as to address remnants from old injuries whether they are symptomatic or not. It all comes together for the organism as a concerted effort in optimal locomotion.

Here on TGG, and in dialogues with Ivo on our podcast, I have long talked about phasic and anti-phasic motions of the arms and shoulder-pelvic blocks during gait and locomotion/sport activity.  I have written several times about the effects of spine pain and how spine pain clients reduce the anti-phasic rotational (axial) nature of the shoulder girdle and pelvic girdle. In the video above, you can see anything but anti-phasic gait, to be clear, this is a classic representation of a phasic gait. The shoulder block and the pelvic block show little if any counter rotation, they are linked together which is not normal gait. Furthermore, if you look carefully, the timing of the right arm swing is variable and cyclically changing in its timing with the left leg. Look carefully, you will see the cyclical success and failure at the beginning of the video.  This is pathologic gait, he must be constantly fighting frontal plane sway because there is no axial anti-phasic motion. He is also constantly fighting the unidirectional rotation that the absence of an entire limb and limb girdle is presenting, you can see him struggle with this if you have looked at enough gait samplings. There is essentially frozen torso movements.  Want to see more of our work on arm swing ? search the gait guys blog.

There is so much more here to discuss, so I will likely return to this video another time to delve into those other things on my mind. Luke is an amazing athlete, he gets much respect from me.

I hope this dialogue helps you to get a deeper grip on gait and gait problems. I have written many articles on the topics of arm swing, phasic and anti-phasic gait, central pattern generators. The are all archived here on the blog. I try to write a new original thought-process article each week for the blog amongst the other “aggregator” type stuff we share from other folks social media. My weekly article serves to go deeper into things, sometimes they are well referenced and in this case, I am basing today’s discussion on the referenced work in the other pieces I have written on arm swing, phasic and anti-phasic gait, central pattern generators etc. So please do your readings there before we begin debate or dialogue, which i always welcome !

Dr. Shawn Allen

Journal of Foot and Ankle Research | Full text | Insertional Achilles tendinopathy is associated with arthritic changes of the posterior calcaneal cartilage: a retrospective study

Chronic achilles-problem clients, slow or non-responders ?
This study suggested that , “Degenerative arthritic changes of the posterior calcaneal wall cartilage characterize patients with IAT (insertional achilles tendonotpathy) and the severity of such changes is directly correlated to the degree of functional impairment.”
Read up… . .

!!!! Don’t deny it, you are curious, and so are we smile emoticon We are easily distracted by bright shiny things and this one sure has the “wait, what the #$%&@ was that !” factor. Inspired by the oversized tires found on &ldq…

!!!! Don’t deny it, you are curious, and so are we smile emoticon We are easily distracted by bright shiny things and this one sure has the “wait, what the #$%&@ was that !” factor.
Inspired by the oversized tires found on “Fat Bikes”, the Michelin® Wild Gripper outsole welcome to the UnderArmor Fat Tire GTX Trail shoe.
2015 “Outside Gear Of The Show” Winner.
Could be a disaster or an ingenious idea. We hope to get a pair to review and let our brethren here know.

https://www.underarmour.com/…/mens-ua-fat-tire-g…/pid1262064

Podcast 95: Head tilt while squatting or running.

We have a strong show for you today. Ankle instability from a neurologic perspective, shoe wear, head tilt and the neurologic and functional complications… we also talk about Efferent Copy and motor learning.

A. Link to our server:
http://traffic.libsyn.com/thegaitguys/pod_95final.mp3

Direct Download:  http://thegaitguys.libsyn.com/pod-95

-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:

Human exoskeletons: The Ekso
http://www.thedailybeast.com/articles/2015/08/03/the-mechanical-exoskeleton-shaping-the-future-of-health-care.html

Ankle muscle strength influence on muscle activation during dynamic and static ankle training modalities
http://www.tandfonline.com/doi/abs/10.1080/02640414.2015.1072640?rfr_id=ori%3Arid%3Acrossref.org&url_ver=Z39.88-2003&rfr_dat=cr_pub%3Dpubmed&#.VcYWR-1VhBc

Chronic ankle instability:

http://tmblr.co/ZrRYjx1akudcm

http://tmblr.co/ZrRYjx1ah6ThV

http://thegaitguys.tumblr.com/post/68785250796/just-because-a-muscle-tests-weak-doesnt-mean-it
http://thegaitguys.tumblr.com/post/117109093439/last-week-we-ran-an-archived-piece-named-just

the future of footwear and orthotics ?
http://lermagazine.com/special-section/conference-coverage/the-future-of-footwear-and-orthoses-is-here-now-what

squats- head posture-gait vision-gravity
http://thegaitguys.tumblr.com/search/vision

Music: brain rhythm
http://www.kurzweilai.net/the-brains-got-rhythm

The Minimalist shoe Rating Scale and Definition

Last year we were two of 42 experts worldwide from 11 countries asked to participate and offer our thoughts in an investigation whose goal it was to come up with a rating scale and definition for minimalist shoes. 

Here is that study: 

A consensus definition and rating scale for minimalist shoes.  Jean-Francois Esculier123, Blaise Dubois13, Clermont E. Dionne14, Jean Leblond2 andJean-Sébastien Roy.   Journal of Foot and Ankle Research 2015, 8:42 

here is a link for that study: http://www.jfootankleres.com/content/8/1/42

This study was performed by very capable and respected folks so you should pay attention. 

Here was their background statement:

“While minimalist running shoes may have an influence on running biomechanics and on the incidence of overuse injuries, the term “minimalist” is currently used without standardisation. The objectives of this study were to reach a consensus on a standard definition of minimalist running shoes, and to develop and validate a rating scale that could be used to determine the degree of minimalism of running shoes, the Minimalist Index (MI).”

We might not do the study justice if we paraphrased the conclusions, so here they are as written,

“The following definition of minimalist shoes was agreed upon by 95 % of participants: “Footwear providing minimal interference with the natural movement of the foot due to its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices”. Characteristics to be included in MI were weight, flexibility, heel to toe drop, stack height and motion control/stability devices, each subscale carrying equal weighing (20 %) on final score.”

So why is this study important ? Well, it creates a common term, a standardized definition, we can all agree upon which is paramount for clear communication amongst professionals in fields (shoe fitters, shoe fabricators, clinicians and researchers) who are dealing with these types of shoes. This study also create a rating scale that will be meaningful to all users in all related fields, again allowing a common dialogue with standardized meaning. From this study they wisely recommended “the shoe industry use such standardised ratings to orientate the running community when selecting their running shoes”.  

This is an important study, it should be part of your knowledge and vocabulary. You should familiarize yourself to the rating scale. 

Shawn and Ivo, the gait guys

Will Smith's new movie "Concussion" terrifies the NFL. Here's the trailer.

Gait and Concussions.

The big movie trailer just came out yesterday, click on the link above to watch the trailer for “Concussion” with Will Smith, slated for theater release in December 2015.  Hopefully this will raise even more awareness to TBI (traumatic brain injury), and remember, minimal TBI falls into these categories and discussions.  

Here is just a small sampling of some of the complications of concussions on human gait.  Head injuries are no joke, their effects on dynamic motor control and sensory-motor integration are potentially serious issues.  From the first 4 references that came up on the pubmed search this is what was mentioned:

- “the ability to control and maintain stability in the frontal plane during walking is diminished under divided attention” (1)

- “Adolescents with concussion displayed increased center-of-mass medial/lateral displacement and velocity during dual-task walking after RTA (return to activity), suggesting a regression of recovery in gait balance control. This study reinforces the need for a multifaceted approach to concussion management and continued monitoring beyond the point of clinical recovery.” (2)

- “concussion may have long-term observable and measurable effects on the control of gait stability”(3)

- “persons with a history of concussion adopt a more conservative gait strategy”.(4)

Do you see something strange on  your client’s gait analysis ?  Have you asked them about previous concussions and head injuries? Perhaps you should.  Take mTBI seriously, this is not a trivial matter. 

Dr. Shawn Allen, one of the gait guys

References:

1. Clin Biomech (Bristol, Avon). 2005 May;20(4):389-95. Epub 2005 Jan 28.The effect of divided attention on gait stability following concussion.Parker TM1, Osternig LR, Lee HJ, Donkelaar Pv, Chou LS.

2. Med Sci Sports Exerc. 2015 Apr;47(4):673-80. doi: 10.1249/MSS.0000000000000462.Return to activity after concussion affects dual-task gait balance control recovery.Howell DR1, Osternig LR, Chou LS.

3.Med Sci Sports Exerc. 2006 Jun;38(6):1032-40.Gait stability following concussion.Parker TM1, Osternig LR, VAN Donkelaar P, Chou LS.

4. Arch Phys Med Rehabil. 2011 Apr;92(4):585-9. doi: 10.1016/j.apmr.2010.11.029.The chronic effects of concussion on gait.Martini DN1, Sabin MJ, DePesa SA, Leal EW, Negrete TN, Sosnoff JJ, Broglio SP.