Where the knee hinges matters.

It is easy to see the big things, but, we sometimes forget that the small things matter.
Sometimes it take an obvious glaring asymmetry to make us appreciate that the small asymmetries can make the same or similar impact over a long period of time. Rivers can carve out canyons over time.

Screen Shot 2018-02-21 at 6.57.19 AM.png

Here we see the gross difference that polio can make in leg size and in leg length. We must remember that changing a leg length also changes the symmetrical relationship of where the 2 knees hinge. A foot that pronates more than the other leg can lower the knee hinge point just a little because the talus drops further from its vertical height. We know very well that it for certain alters the hinge direction, posturing it more medially, but we cannot forget that a cranky knee on a side where the foot is flatter or pronates more excessively than the other is not to be ignored.
In this photo, we have dotted the knee at the same point on the patella. It is clear the knees will not hinge at the same time, thus stride and step lengths will change, and step width will be impacted. The pelvis will also spin more to one side on a pelvis that is lower on one side. This will impact lumbar spine sagittal happiness and stability/mobility. Hip and pelvis drift are real things in this case, and need your attention. *Just like a client that has a painful foot, a more pronated foot, more tibial torsion on one side etc. these things matter, and they often matter years down the road when many thousands of miles have been clocked into the subtle asymmetry. Sometimes these little things matter in our athletes too, who put the pedal to the floor asking the body for more.

Come hear our lecture tonight on www.onlineCE.com. You have to sign up early to get in. We won't disappoint. See you then. 7pm central time.

Conservative Mangement of Parkinsons

Most, if not all of us have either patients, family or friends that have been touched by PD. Here is a video talking about some of the conservative approaches from the literature. We don't talk about gait specifically, but because it is a movement disorder, we felt it appropriate to share.

Do you really need your 5th "pinky" toe ?

This little piggy went to market  . . . . .  as the nursery rhyme goes.

rewind blog post for your enjoyment

Do I Really Need My Pinky Toe?

Just the other day we saw this article in Popular Science written by Sally Zhang.  Sally obviously does not read our blog, but she got a lot of stuff right.

“If you’re born without a pinky toe or have an accident and it’s removed, you can completely do everything you wanted to do,” Dr. Anne Holly Johnson, instructor in orthopaedic surgery at Harvard Medical School, says.

Above you will see a photo of one of the gait guy’s feet.  It is quite clear from the photo that competent use of the pinky toe is not necessary for adequate, and possibly exceptionally skilled, foot function.  Here, check out this video of our foot in these 2 videos (here and here) for some advanced foot function (sans pinky toe). As you can see in the photo above, this 5th toe has likely never felt the ground, this is a fixed deformity.  Flexor and extensor function of the toe are intact, but it does not reach the ground and so assistance in gaining adequate purchase of the 5th metatarsal on the ground is absent. 

This brings us to a deeper question, what about the 5th metatarsal then? Is it necessary ?  Our answer even without deeper research is a solid “yes”. The foot tripod is severely compromised without the 5th metatarsal. The lateral stability of the foot is impaired without the 5th MET.  The natural locking of the calcaneocuboid joint mechanism will be impaired, the peroneal muscles that provide such critical lateral ankle and foot stability will have fascial planes and tendon attachments disengaged, the natural walking gait lateral to medial foot progression would be impaired, propulsion would be impaired and the list goes on and on. And, not even on the local foot/ankle level. Because, if you take out the function and stability of the lateral foot the hip is very likely to suffer lateral (frontal plane) stability deficits. Meaning, the gluteus medius and abdominal obliques will have more difficulty guarding frontal plane drift when in stance phase rendering all of the “cross over gait” risks (link) highly probable.  

So, not much exciting stuff here today. The presence of a functioning pinky toe does not appear to be critical but don’t take away its big brother neighbor, the 5th Metatarsal or trouble is just around the corner. Don’t believe us? Just ask anyone with a non-union fracture (Jones fracture) of the 5th metatarsal.

The answer goes back to the evolutionary history of humans, explains Dr. Anish Kadakia, assistant professor in orthopaedic surgery at Northwestern University. "Primates use their feet to grab, claw, to climb trees, but humans, we don’t need that function anymore,“ Kadakia says. "Clearly we’re not jumping up and down trees and using our feet to grab. We have toes embryologically, evolutionary for that particular reason because we descended from apes, but we don’t need them as people.”

The gait guys, working with 4 toes on each foot, one step ahead of evolution it seems.

Shawn and Ivo,

The gait guys




How the CNS adapts. Exploratory testing of the ground.

Screen Shot 2018-02-16 at 8.33.03 AM.png

What is happening at the 150 meter mark in a 200m sprint when that glute starts to fatigue ? What is happening at the 12th mile in a half marathon when stabilzation around that knee starts to falter?
In this article below, the authors discuss postural adaptations to unilateral hip muscle fatigue. This study merely looks at the effects during standing, so imagine what happens during locomotion when things start to fatigue.

Anyone who has sprained an ankle or banged up a knee knows what it is like to have an automated limping gait. The CNS is trying to reduce and shorten the loading response (and time) on the affected limb. This scenario goes on for awhile, days, maybe weeks, until it becomes somewhat more automated.
We just saw a client in the office just yesterday who had a subtle limp from a foot fracture 6 months ago. I mentioned it in passing, "isn't it amazing that your CNS can still be generating that limping adaptive gait even after 6 months, even now that the pain is no longer present?" His response, "What ? I am still limping? No I'm not ! Am I? Really?" I showed him the video, he was shocked. Things get automated, the CNS adapts, and it often doesn't know when to let go of an adaptive pattern even when it is no longer warrented. It is amazing to think that the brain often cannot logically process the incoming data and revert back to the sensory-motor program that was engaged pre-injury. Amazingly, perhaps the brain still knows better, perhaps it knows that things might seem fine, but lurking beneath the surface the sensory receptors are still sending soft warning signs that things still are not kosher.
We say something like this often to our clients, "The CNS makes momentary adaptive choices, but it has no way of foreseeing the consequences of an adaptive measure which is necessary in the moment. It makes these choices based on perceived stability, necessary mobility, economy, and pain avoidance, most of the time. But, it has no way of seeing into the future to see whether its choices have ramifications, it just chooses what makes the most sense in that moment." This is one of the reasons why we get so cranky about people who offer training and corrective exercise queues to people without deep thought, examination, and consideration. There can be ramifications down the road, that, in the present, are unseen and unknown. For example, just because you are running faster because you altered or augmented a client's arm swing, doesn't mean that newly trained pattern, that might even have the positive performance outcomes, won't have consequences that need to be walked back in the future. This is one of the premises of our recent arguments with the HOF (Head over Foot) crowd, who explicitly convey they only care about the clock and a client's speed, not about their well being down the road. There is no free lunch, the piper always gets paid, but just because we are not there to see the payment, it doesn't mean the day of reckoning isn't coming. We have been playing this human mechanic game now collectively for about 50 years, we know the payback is real, we see it often, eventually the tab for that free lunch shows up.

In this article below, the authors discuss postural adaptations to unilateral hip muscle fatigue. We are again looking for that Piper, he wants to get paid, so what is the consequence to the fatigue ? This study merely looks at standing, so imagine what happens during locomotion when things start to fatigue.

"The purpose of the present experiment was designed to address this issue by assessing the effect of unilateral muscle fatigue induced on the hip's abductors of the dominant leg on bipedal standing."

"Results of the experimental group showed that unilateral muscle fatigue induced on the hip's abductors of the dominant leg had different effects on the plantar CoP displacements (1) under the non-fatigued and fatigued legs, yielding larger displacements under the non-fatigued leg only, and (2) in the anteroposterior and mediolateral axes, yielding larger displacements along the mediolateral axis only. These observations could not be accounted for by any asymmetrical distribution of the body weight on both legs which were similar for both pre- and post-fatigue conditions. The observed postural responses could be viewed as an adaptive process to cope with an unilateral alteration in the hip neuromuscular function induced by the fatiguing exercise for controlling bipedal stance. The increase in CoP displacements observed under the non-fatigued leg in the fatigue condition could reflect enhanced exploratory "testing of the ground" movements with sensors of the non-fatigued leg's feet, providing supplementary somatosensory inputs to the central nervous system to preserve/facilitate postural control in condition of altered neuromuscular function of the dominant leg's hip abductors induced by the fatiguing exercise." - Vuillerme et at, 2009

We have discussed arm swing many dozens of times over the 9 years of blogging research on the web. You can search our blog for "arm swing" and go down the deep rabbit hole we have dug if you wish to learn how arm swing is not only necessary, but highly adaptive ballasts to help maintain balance and effective and adaptive locomotion. They can be used for improving or changing locomotion of all types. They can be looked at as prime movers or passive followers of the higher order leg swing. They can be coached right and wrong. The have a huge impact on COM (center of mass) and COP (center of pressure). And as a tangential comment of the article above, when the adaptive postural responses of the body are activated from a given fatigue in the body, COM and COP must change and adapt to keep us upright in the gravitational plane. These COM and COP changes are exploratory postural compensations, of which altered arm swing is often one adaptive and assistive measure. In this articles discussions, these compensations provide supplemental somatosensory inputs to the central nervous system to "preserve/facilitate postural control in conditions of altered neuromuscular function" when fatigue sets in somewhere. Bringing this all full circle, changing someone's arm swing, because you do not like how it looks (ie asymmetry, cadence, direction, etc), is foolish. The brain is doing it, because it likely has to do it to help adapt to a problem elsewhere that is altering the brain's perception of a safe COP and COM. Your job is to find out why and correct it, not to teach them a new way, which is very likely a new compensation to their already employed adaptive compensation.
-Shawn Allen, the other gait guy

Postural adaptation to unilateral hip muscle fatigue during human bipedal standing. Vuillerme N1, Sporbert C, Pinsault N. Gait Posture. 2009 Jul;30(1):122-5. doi: 10.1016/j.gaitpost.2009.03.004. Epub 2009 Apr 28.

Too much extensor tone: The banana toe.


Too much extensor tone.
We are often talking about the subtle balanced relationship of the long and short toe flexors and extensors. We often discuss that hammer toes are too much long flexor and short extensor tone (with too little in the short flexor and long extensor).
Here we see the opposite. We see too much long extensor tone (note the upward banana-shaped orientation of the big toe). When this foot is on the ground, the pad and distal 1/2 of the big toe does not even touch the ground, standing or in gait. IF you look closely at the blown up pic, you can sort of see (sorry, should have taken more pics) the increased callus development in the contact area of the short flexor attachment (FHB, flexor hallucis brevis).


This relationship is the opposite of the above with hammer toes. Too much long extensor, too much short flexor, and not enough long flexor and short extensor. These clients need more homework for long flexor and short extensor. This is one of the reasons why we developed the exercise below in the youtube link.

Toe Break


Here's on one of our favorite subjects: toe break:

No, this is not a post about fractures phalanges, but rather where your shoe bends, or should bend.

Toe break is where the shoe bends anteriorly. Ideally, we believe this to be at the 1st metatarsal phalangeal joint and metartarsal phalangeal articulations. This allows for the best “high gear” push off as described by Bojsen-Moller (1) High gear push off means that the pressure goes to the base of the great toe (1st MTP joint) for push off. (for an interesting post on this, see here .

If we think about rockers of the foot during the gait cycle (need a review? click here), it seems best that we accommodate each of them to the best of our abilities. Since most of us wear shoes, it would make sense that it flex in the right places. With regards to the forefoot, it should (theoretically) be under the 1st metatarsal phalangeal joint. This should provide both optimal biomechanical function (distribution of force to the 1st metatarsal phalangeal joint for push off/ terminal stance) and maximal perceived comfort (2).

If the shoe bends in the wrong place, or DOES NOT bend (ie, the last is too rigid, like a rockered hiking shoe, Dansko clog, etc), the mechanics change. This has biomechanical consequences and may result in discomfort or injury.

If the axis of motion for the 1st metatarsal phalangeal joint is moved posteriorly, to behind (rather than under) the joint, the plantar pressures increase at MTP’s 4-5 and decrease at the medial mid foot. If moved even further posteriorly, the plantar pressures, and contact time in the mid foot and hind foot (3). A rocker bottom shoe would also reduce the plantar pressures in the medial and central forefoot as well (4). It would stand to reason that this would alter gait mechanics, and decrease mechanical efficiency. That can be a good thing or a bad thing, depending on what you are trying to accomplish.

Take home messages:

    Where a shoe flexes will, in part, determine plantar pressures
    Changes in shoe flex points can alter gait mechanics
    More efficient “toe off” will come from a shoe flexing at the 1st metatarsal phalangeal joint and across the lesser metatarsal phalangeal joints
    examine the “toe break” in your clients shoes, especially of they have a foot problem

1. F Bojsen-Møller Calcaneocuboid joint and stability of the longitudinal arch of the foot at high and low gear push off. J Anat. 1979 Aug; 129(Pt 1): 165–176.

2. Jordan C1, Payton C, Bartlett R Perceived comfort and pressure distribution in casual footwear. Clin Biomech (Bristol, Avon). 1997 Apr;12(3):S5.

3. van der Zwaard BC1, Vanwanseele B, Holtkamp F, van der Horst HE, Elders PJ, Menz HB Variation in the location of the shoe sole flexion point influences plantar loading patterns during gait. J Foot Ankle Res. 2014 Mar 19;7(1):20.

4. Schaff P, Cavanagh P Shoes for the Insensitive Foot: The Effect of a “Rocker Bottom” Shoe Modification on Plantar Pressure Distribution Foot & Ankle International December 1990 vol. 11 no. 3 129-140

plantar pressure image above from : Dawber D., Bristow I. and Mooney J. (1996) “The foot: problems in podiatry and dermatology”, London Martin Dunitz Medical Pocket Books.


Childhood Long Bone Torsions: Neurodevelopmental Considerations

Key Tag words:  torsions, gait, long bone torsions, femoral torsion, tibial torsion, neuromotor, neuroscience, locomotion, DNS, ambulation, walking, running, gait analysis, infant gait, childhood gait, jiu jitsu, crossover gait, cross over, vestibular, Parkinson's disease

We hit some good topics today, from childhood torsional issues, fix or leave alone ? What to look for when first observing and examining your client's gait plus Balance and vestibular function in gait and bike riding, exercise and neurodegenerative disorders and diseases and even developing proper neuromotor patterns, and inhibiting improper ones.
Plus we hit a favorite topic, the cross over gait and Ivo hits some highlights on gating inhibitory pathways.

Links to find the podcast:

iTunes page: https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138?mt=2

Direct Download: http://traffic.libsyn.com/thegaitguys/pod_134_Final.mp3

Permalink URL: http://thegaitguys.libsyn.com/childhood-long-bone-torsions-neurodevelopmental-considerations

Libsyn URL: http://directory.libsyn.com/episode/index/id/6247612

Our Websites:

summitchiroandrehab.com doctorallen.co shawnallen.net

Our website is all you need to remember. Everything you want, need and wish for is right there on the site.
Interested in our stuff ? Want to buy some of our lectures or our National Shoe Fit program? Click here (thegaitguys.com or thegaitguys.tumblr.com) and you will come to our websites. In the tabs, you will find tabs for STORE, SEMINARS, BOOK etc. We also lecture every 3rd Wednesday of the month on onlineCE.com. We have an extensive catalogued library of our courses there, you can take them any time for a nominal fee (~$20).

Our podcast is on iTunes and just about every other podcast harbor site, just google "the gait guys podcast", you will find us.

Show Notes:

Stacking of the joints. A Runner's dilemma ?

You've heard us say it again and again, do not coach out arm swing dislikes if you have not addressed the problems in the lower limbs (including pelvis, hips knees etc). Look at this photo, clearly left hip frontal plane sway, and right arm swing frontal plane sway. It is not a coincidence. Those 2 limbs are neurologically paired. The arm is acting like a ballast in the opposite frontal plane to help her stay centered. She is failing, compensating, but at least not falling over. Focusing on the cause(s) of the left frontal pelvis-hip drift would be our direction, not coaching out the arm swing. We rarely, if ever, coach changes to arm swing. We have posted articles in the past that confirm that arm swing is more passive, and subservient to leg swing motor pathways.
Read on . . .


The effect of Arm swing on lumbar spine and hip joint forces.

We have discussed the arm swing issue so many times over the years that we have lost count. By many sources, arm swing is a product of lower limb action and a product of the effective, or ineffective, relationship between the shoulder "girdle" (maybe thoracic rotation component) and the pelvic girdle (lumbopelvic rhythm) during gait. This is the concept of phasic and anti-phasic limb swing. If you want to dive into that, and you should if you are unfamiliar with the concept, you can look it up on our blog using the search box. We are not to forget that the arms, and thus arm swing, is a major factor in maintaining balance. We have used the term "ballast" many times to describe the effects of arm swing, rotation, abduction, circumduction etc on assisting balance maintenance of the body during various locomotion strategies. These are largely subconscious actions, hence why we agree with the research suggesting that arm swing is secondary, compensatory, and takes its queues off of the activity of the lower limb motor actions. In essence, arm swing variants are necessary compensations to assist in maintaining things like balance, center of pressure, equilibrium and the like.

In this recent 2017 study, we have another suggesting arm swings function in assisting, even improving, dynamic stability. We are reminded of MdGill's suggestion, and the concepts of phasic and antiphasic torso-pelvis counter rotational movements, of how spinal loads can be affected by changes or differences in arm position. Even arm position changes in sitting and standing can alter spinal loads, so during movement it is a virtual guarantee.

This study looked at "how arm swing could influence the lumbar spine and hip joint forces and motions during walking." In this study, the researchers had each subject perform walking with different arm swing amplitudes and arm positions. Here is a comment from the researchers on what they found, it is pretty much what we have been writing about for several years based off of other research"

"The range of motion of the thorax with respect to the pelvis and of the pelvis with respect to the ground in the transversal plane were significantly associated with arm position and swing amplitude during gait. The hip external-internal rotation range of motion statistically varied only for non-dominant limb. Unlike hip joint reaction forces, predicted peak spinal loads at T12-L1 and L5-S1 showed significant differences at approximately the time of contralateral toe off and contralateral heel strike."

Thus, we find yet another study confirming what many will say is obvious, that being arm position and movements have notable effects on whole body kinetics and spinal loads. This study suggested that arm variations did not have an effect on spinal loads during walking. We find this curious; it is something we will be looking into, and pondering. We hope you do as well.

Effect of arm swinging on lumbar spine and hip joint forces
Lorenza Angelini et al. Journal of Biomechanics, Sept 2017

Try THIS at home...

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Cool test, results you can see and some literature to back it up. If you are interested at all in proprioception, this is an interesting read.

So, the question for us is: "Does ankle dorsiflexion actually create more stability, like is purported?"

“The point is that if I make their ankle rigid this way, then they can more effectively use the balance mechanisms at their knees, hips, and proximally, because they’re on a stable base. My proposition is that their balance is actually normal, apart from that distal segment. When their ankle is stabilized, they use their knees more effectively, and they become less dependent on their eyesight to maintain their balance.”


The Calcaneo Cuboid Locking Mechanism...Revisited...

Do you know what this is? You should if you treat folks who walk or run!

It is the mechanism by which the tendon of the peroneus longus travels behind the lateral malleolus of the ankle, travels underfoot, around the cuboid to insert into the lateral aspect of the base of the 1st metatarsal and adjacent 1st cunieform. Remember the peroneus longus?

The peroneus (or fibularis) longus arises from the head and upper two-thirds of the lateral surface of the fibula, from the deep surface of the fascia, and from the intermuscular septa between it and the muscles on the front and back of the leg; occasionally also by a few fibers from the lateral condyle of the tibia.  You can see from it attachments that it can influence the entire upper lateral leg.

It’s tendon runs down the fibular shaft, wraps around the lateral malleolus, travels obliquely under the foot, crossing the lateral cuboid (which it everts after midstance to help with supination) crosses the sole of the foot obliquely, and inserts into the lateral side of the base of the first metatarsal and lateral aspect of the 1st cunieform.  

It acts from just prior to heel strike to limit excessive rearfoot inversion, through midstance to decelerate subtalar pronation and assists in stabilization of the midfoot articulations, and into terminal stance and pre swing to lock the lateral column of the foot for toe off and plantar flex the 1st ray (creating a good foot tripod), allowing dorsal posterior shift of the 1st metatarsal-phalangeal joint axis (necessary for dorsiflexion of the hallux (big toe)).

When the peroneus longus contracts, in addition to plantar flexing the 1st ray, it everts the cuboid and locks the lateral column of the foot, minimizing muscular strain required to maintain the foot in supination (the locked position for propulsion). Normally, muscle strength alone is insufficient to perform this job and it requires some help from the adjacent articulations.

In addition, the soleus maintains spuination during propulsion by plantar flexing and inverting rear foot via the subtalar joint. This is assisted by the peroneus brevis and tertius which also dorsflex and evert the lateral column, helping keep it locked. Can you see why the peroneii are so important?

signs of a faulty calcaneo cuboid locking mechanism

  • weak peroneus longus, brevis and or tertius
  • excessive rear or midfoot pronation
  • low arch during ambulation
  • poor or low gear “push off”
  • subluxated cuboid


The calcaneo cuboid locking mechanism. Essential for appropriate supination and ambulation. Insufficiency, coming to a foot you will soon examine.

Sagittal gait change in arthritic hips.

Asymmetries are the norm, whether they are anatomic or functional. This however does not mean that there may, or may not, be present or future consequences to the asymmetries.  It can take time for compensations to develop to accommodate these compensations, and it may take even further time for the body to present (and perhaps not present) consequences to the compensations.

In this study, progressing osteoarthritis in the hip began to eat away as some functional parameters that might otherwise have allowed for more symmetrical step and strike lengths, and one must not forget step width has to be in this discussion as well. 

"The patients walked significantly slower than the controls (p=0.002), revealed significantly reduced joint excursions of the hip (p<0.001) and knee (p=0.011), and a reduced hip flexion moment at midstance and peak hip extension (p<0.001). Differences were primarily manifested during the latter 50% of stance, and were persistent when controlling for velocity." - Eitzen et al.

Thus, to walk a straight line, some adaptive compensations will have to occur in the body to enable a linear progression. This might mean altering hip extension patterns, altering hip rotation relationships within the affected hip and thus of the contralateral hip (which might lead to pelvis distortion patterning), pelvis drift in the frontal plane, pelvis drift in the sagittal plane (APT, PPT), asymmetries in spinal rotation and thus arm swing, to name a few just regionally at the hip-pelvis-spine interval. Adaptations must be made. The question is, does your gait assessment afford you the insight to be addressing the problem, or merely their visible compensation, that is the hard part.  And remember what we always say, you gait analysis is only going to show you what your client is doing, not why they are doing it. Thus, fixing what you see is likely not fixing
"the why".

"Reduced gait velocity, reduced sagittal plane joint excursion, and a reduced hip flexion moment in the late stance phase of gait were found to be evident already in hip osteoarthritis patients with mild to moderate symptoms, not eligible for total hip replacement. " - Eitzen et al.

* Differences were primarily manifested during the latter 50% of stance, and were persistent when controlling for velocity.


BMC Musculoskelet Disord. 2012 Dec 20;13:258. doi: 10.1186/1471-2474-13-258.
Sagittal plane gait characteristics in hip osteoarthritis patients with mild to moderate symptoms compared to healthy controls: a cross-sectional study.
Eitzen I1, Fernandes L, Nordsletten L, Risberg MA.

Body Composition and gait speed.

"In older adults, every 0.1-m/s slower gait speed is associated with a 12% higher mortality. However, little research has identified risk factors for gait-speed decline."

Reduction in activity, particularly challenging difficult activity, stuff that asks a little more from you, the typical stuff that the elderly do not wish to engage in, is a bigger piece to their gait and movement decline that they likely think.

Conclusions: "High and increasing thigh intermuscular fat are important predictors of gait-speed decline, implying that fat infiltration into muscle contributes to a loss of mobility with age. Conversely, a decreasing thigh muscle area is also predictive of a decline in gait speed."


Am J Clin Nutr. 2013 Mar;97(3):552-60. doi: 10.3945/ajcn.112.047860. Epub 2013 Jan 30.

Associations between body composition and gait-speed decline: results from the Health, Aging, and Body Composition study.

Beavers KM1, Beavers DP, Houston DK, Harris TB, Hue TF, Koster A, Newman AB, Simonsick EM, Studenski SA, Nicklas BJ, Kritchevsky SB.

Internal hip rotation and low back pain.

Internal hip rotation and low back pain.

No brain surgery here if you have been on our station for the last several years. We pound home the critical importance of internal hip rotation all the time, here and in our clinic.
When the foot is on the ground, loading, the opposite leg is in swing. Part of this swing phase requires the hemipelvis on that swing side to also advance forward as well. This means that the stance phase leg will see the pelvis rotating atop of the static femoral head, this rotation is internal hip rotation. If one does not have sufficient internal hip rotation then the heel will be lifted prematurely, the foot might undergo an adductory twist (the heel moves medially into adduction which can look like the foot spinning "relatively" outward into external rotation) to name just a few (of many possible) pattern consequences. The loads can also move up into the lumbar spine, because, if the rotation is not there in the hip, or not buffered there, it either moves down into the limb or up into the pelvis and spine, or both. There are many strategies and patterns of loading responses available to the framework, it is your job to find them, source out the problem, and remedy. One must look for and understand the importance of sufficient internal hip rotation in your client, and the ramifications when it is not sufficiently present.
This study brings this principle to mind.


Have impaired ankle rocker or ankle dorsiflexion ? Try out these shoes.

Have impaired mid or forefoot rockers?

This will come to little surprise to anyone who has been here awhile at TGG. But I finally got around to putting on a pair of the HOKA Bondi 5 recently and boy was I surprised how much rocker was built into the forefoot. I can now see why there is such a dramatically beneficial response to patients with a painful hallux joint complex. I had been in their Claytons and Cliftons before to trial them out, but never a pair of Bondi 5's.
If you have a client with impaired mid to late stage ankle rocker or forefoot rockers (there are 3 rockers, Heel Rocker, Ankle rocker, and Forefoot Rocker) this shoe will buffer the loads. It is no replacement for attempting to remedy biomechanical faults or limitations, but , if you have a client where solution is not available and management of loads i the only way, then this shoe will be a gem to you and the client. Go try a pair on so you know what we mean. The rocker is massive and effective, and one might argue, a little excessive (but we are not complaining). The Dansko clog can be another alternative for some clients.

Changes in running kinematics and kinetics in response to a rockered shoe intervention.
Boyer KA, Andriacchi TP.
Clin Biomech (Bristol, Avon). 2009 Dec;24(10):872-6. doi: 10.1016/j.clinbiomech.2009.08.003. Epub 2009 Sep 9.

Hoka Bondi or Dansko Clog

Neuromechanical adaptations in achilles tendinosis

It is not just about the tendon. A perspective on asymmetry.

We are coming back to this important article again.
When you have a tendon problem, you have other problems. There is the muscle-tendon relationship, there is the CNS component, and there are the other muscles regionally within the related loaded chains. Because of these multiple integrated components, this "illustrates the human body's capacity to adapt to tendon pathology and provide the physiological basis for intervention or prevention strategies".
"If a component in the loop loses its integrity, the entire system has to adapt to that deficiency. "
We have discussed on recent TGG podcasts this important ability of a tendon to have sufficient stiffness, to be more precise, to produce sufficient stiffness. Degenerative tendons exhibit less stiffness and so when this issue is present, we move into the adaptive strategies of the entire system that was alluded to above. Adaptation begins; agonist, synergist, antagonist muscles, CNS, motor pattern adaptive patterns ensue.
It has been suggested by this study that these compensations are unilateral, on the affected side, thus driving asymmetrical neuromechanical adaptations.


Cannabis users walk differently.

We all have experienced or viewed the alcohol impaired gait at some point in our lives, the sloppy malcoordinated limb and torso movements. There are some classic observable characteristics there that many of us are familiar with. But what about cannabis gait ?

"The research from the University of South Australia, published in the journal Drug and Alcohol Dependence, found those who smoke cannabis tend to move their shoulders less and elbows more as they walk. The pilot study also found marijuana users swing their knees more quickly during walking. The differences in gait were small and found in people who smoked a light or moderate amount of cannabis. Some changes were so small it was impossible for a specialist to detect."

However, the thing we found interesting was the papers final question, as to whether the subtle gait changes over a longer period of time would increase or become more apparent.

*We have seen this variation in arm swing gait many times before. We have discussed numerous times that when there is a reduction in the normal shoulder and pelvic "girdle" counter rotations, the normal antiphasic gait that presents us with the clearly obvious opposite arm-leg swings, we lose the ability to tap into these oscillations that afford us this free arm and leg swing. So, when these girdle rotations are reduced, the limb movement has to come from further down into the limb, from elbow movement, a sort of casting the lower arm forward from biceps and triceps activity and from a kicking forward of the lower leg from quadriceps activity instead of hip flexion-extension activity.

Gait affects everything, and everything seems to affect our gait.


Lumbar spine mechanics and boots

Your footwear can affect your hips and low back ? Yes.

If you have been with us even a short while, this study should be of zero new value to you. But this study looked at the ankle dorsiflexion restricting firefighting boots on the low back.
We know that there are several force dissipators in the lower limbs, those being hip flexion, knee flexion and ankle dorsiflexion not to forget the all important foot pronation. When one of those is compromised, the job of that joint complex typically gets shunted elsewhere, and often proximally into the body.
Obviously, above ankle boots will restrict ankle dorsiflexion. Imagine an ice skate laced up all the way, or a ski boot, the ankle dorsiflexion virtually disappears. The came can happen in an inappropriately laced hiking boot or high ankle trail running shoe.
This will hit home the posts earlier in the week on the "z-angle" we discussed and Gray Cooks video from the weekend.
It is possible if you dial back the ankle dorsiflexion you cheat hip extension, or you make the lumbar spine extend into more lordosis than it is happy to perform.
You just cannot rob Peter to pay Paul all the time. Eventually Peter is gonna get pretty pissed.


More on the Z-angle

More on the "Z-angle". Why your hip and ankle have to talk to each other.

We have been saying this kind of stuff for years, but in this video perhaps Gray Cook says it in a way that will resonate well with some when we can be a bit too wordy at times, Gray is always eloquent and well spoken. We often discuss this ankle and glute relationship he mentions in a topic we refer to as "the Z- angle". And, we discuss the greater global ramifications of unresolved ankle sprains. Search our blog for these terms and topics.
It is rare that our in-office therapy and our corrective home work for a client does not address both the ankle and hip simultaneously. We know this tight relationship exists, and so should you.
In many of our podcasts and blog posts we pound sand on the fact that just because you have ankle mobility on the exam table does not mean you will have it available in some movement patterns or in some of your sport movements. And, ankle functional impairments are key players in multiple injuries and impaired movement patterns. We like the "software vs hardware" terminology he uses, we will be borrowing that verbiage in the future, it is a nice way to tighten up a dialogue without getting wordy. Great job as always Gray !

Forefoot Varus vs Forefoot Supinatus


We talked about forefoot varus, forefoot supinatus and subsequent biomechanics in a recent onlinece.com course. Here is a great commentary on a review article we discussed as well as a great explanation about thew tru differences between at forefoot varus (rare) and the more common forefoot supinatus.

Take home message? FROM THE ARTICLE:

" In summary: both look the same, but they are totally different beasts:

    a forefoot varus is bony and a forefoot supinatus is soft tissue
    a forefoot varus is a cause of ‘overpronation’ and a forefoot supinatus is the result of ‘overpronation’
    a forefoot varus is rare and a forefoot supintus is common
    a forefoot varus cannot be corrected and a forefoot supinatus can be corrected"