Hip Abduction moment?

This was a great question we received, so we thought we would make a post of it, so everyone could benefit.

“@GregLehman: @KineticRev @TheGaitGuys do you guys have a link to your thoughts on how an ER leg allows the quads to create a hip abductor moment? Thanks”

First of all, What IS a hip abduction moment?

In posts, we often refer to a “moment”, meaning almost literally, a few seconds where a certain motion occurs. When are watching someone from behind and see their heel adduct as they get to terminal stance and pre swing (just before they toe off), you are seeing an “adductory moment” of the heel, sometimes referred to as an “adductory twist”.

Now lets think about the hip. Have you ever seen a framing square used by a carpenter? It is an “L” shaped device to make sure things are square (like hanging a door). The hip is kind of like this. It is shaped like an “L” with the neck and head forming the shorter side of the “L” and the femoral shaft forming the longer side. If you imagine the short side of the square attached to the pelvis and now hinging that away from the body, you have abduction of the hip. Normally, this task is tended to (primarily) by the middle fibers of the gluteus medius and posterior fibers of the gluteus minimus, assisted by the quadratus lumborum on the opposite side.

How can the quad be involved?

We remember that the quadriceps has four parts, the vastus lateralis, vastus intermedius and vastis medialis (collectively called “the vasti’) and the rectus femoris.

The rectus femoris proximal attachments are at the anterior inferior iliac spine (this is called the straight or anterior head) and the superior lip of the acetabulum (called the reflected or posterior head) Please see the top of the 2^nd picture above, you can see the 2 heads. The distal attachment, after blending with the vasti, is into the patellar tendon and ultimately the tibial tuberosity.

The rectus is an accessory hip flexor and knee extensor, though it not normally a prime mover for either of these motions. It’s amount of action depends on the position of both the knee and hip.  When the knee is flexed, the rectus has less mechanical advantage, because it is placed in a lengthened position; same goes if the hip is extended.  It will be shortened if the hip is flexed and if the knee is extended at the same time, will have a mechanical disadvantage.

Now think about the direction of travel of each of the heads.

The “straight” head actually runs more obliquely from lateral to medial from its proximal attachment (AIIS) to the distal attachment (blending with vasti and patellar tendon); the refelected head runs a similar course, but not as oblique. If you were to externally rotate the thigh (remember, some folks may have an externally rotated foot due to external tibial torsion), it would actually give these heads more mechanical advantage (when the knee is relatively extended, such as at heel strike/ initial contact and toe off/ preswing) as abductors (remember to think from the ground up, closed chain, so the distal attachments are acting more like the origin); thus, the abductor moment we have talked about.

There you have it @Greglehman. Thanks for the great question.

The Gait Guys. Uber Gait Aficionado’s Extraordinaire. Come and learn with us. Watch us on Youtube; follow us on Facebook and Twitter, see many of our downloads on our payloadz site by clicking here.

All material copyright 2013 the Gait guys/ The Homunculus Group. All rights reserved; don’t make us call Lee.

Join Us Wednesday Evening

We are doing our monthly lecture on chirocredit.com on Wednesday Evening, 8 PM EST (7 central, 6 mountain, 5 west coast). Get credit and get entertained at the same time. Look for Biomechanics 311

Aloha

Ivo and Shawn

The Power of Facilitation: How to supercharge your run.

While running intervals this crisp, cool 19 degree morning, something dawned on me. My left knee was hurting from some patellar tracking issues, but only on initial contact and toe off. I generally run with a midfoot strike. I began concentrating on my feet, lifted and spread my toes and voila! my knee pain instantly improved. Very cool, and that is why I am writing this today. 

Without getting bogged down in the mire of quad/hamstring facilitation patterns, lets look at what happened.

I contracted the long extensors of the toes: the extensor digitorum longus and the extensor hallicus longus; the short extensors of my toes: the extensor digitorum brevis, the extensor hallucis brevis: as well as the dorsal interossei.the peroneus longus, brevis and tertius were probably involved as well.

Do you note a central theme here? They are all extensors. So what, you say. Hmmm… 

Lets think about this from a neurological perspective:

In the nervous system, we have 2 principles called convergence and divergence. Convergence is when many neurons synapse on one (or a group of fewer) neuron(s). It takes information and “simplifies” it, making information processing easier or more streamlined. Divergence is the opposite, where one(or a few) neurons synapse on a larger group. It takes information and makes it more complicated, or offers it more options.

In the spinal cord, motor neurons are arranged in sections or “pools” as we like to call them in the gray matter of the cord. These pools receive afferent information  and perform segmental processing (all the info coming in at that spinal cord segment) before the information travels up to higher centers (like the cerebellum and cortex). One of these pools fires the extensor muscles and another fires the flexor muscles.. 

If someone in the movie theater keeps kicking the back of our seat, after a while, you will say (or do) something to try and get them to stop. You have reached the threshold of your patience. Neurons also have a threshold for firing.  If they don’t reach threshold, they don’t fire; to them it is black and white. Stimuli applied to the neuron either takes them closer to or farther from threshold.  When a stimulus takes them closer to firing, we say they are “facilitating” the neuron. If it affects a “pool” of neurons, then that neuronal pool is facilitated. If that pool of neurons happens to fire extensor muscles, then that “extensor pool” is facilitated.

When I consciously fired my extensor muscles, two things happened: 1. Through divergence, I sent information from my brain (fewer neurons in the cortico spinal pathway) to the motor neuron pools of my extensor muscles (larger groups of motor neurons) facilitating them and bringing them closer to threshold for firing and 2. When my extensor muscles fired, they sent that information (via muscle spindles, golgi tendon organs, joint mechnoreceptors, etc) back to my cerebellum, brain stem and cortex (convergence) to monitor and modulate the response.

When I fired my extensor muscles, I facilitated ALL the neuronal pools of ALL the extensors of the foot and lower kinetic chain. This was enough to create balance between my flexors and extensors and normalize my knee mechanics.

If you have followed us for any amount of time, you know that it is often “all about the extensors” and this post exemplifies that fact.

 Next time you are running, have a consciousness of your extensors. Think about lifting and spreading our toes, or consciously not clenching them. Attempt to dorsiflex your ankles and engage your glutes. It just may make your knees feel better!

The Gait Guys. Facilitating your neuronal pools with each and every post.

All material copyright 2013 The Gait Guys/ The Homunculus Group. All rights reserved. If you rip off our stuff, we will send Lee after you!

Podcast 41: The Ankle Dorsiflexion Podcast.

Today we talk about many things affecting, impairing, and relating to ankle dorsiflexion, and so much more ! Join us today on The Gait Guys podcast !

A. Link to our server:

http://thegaitguys.libsyn.com/podcast-41-the-ankle-dorsiflexion-podcast

B. iTunes link:

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

C. Gait Guys online /download store (National Shoe Fit Certification and more !) :

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

D. other web based Gait Guys lectures:

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

________________________________________

* Today’s show notes:

Neuroscience:

1. Brains Sweep Themselves Clean Of Toxins During Sleep

http://www.npr.org/blogs/health/2013/10/17/236211811/brains-sweep-themselves-clean-of-toxins-during-sleep

2. Harvard creates cyborg skin

http://www.extremetech.com/extreme/135207-harvard-creates-cyborg-flesh-thats-half-man-half-machine

 

3. Wearable tech

http://news.cnet.com/8301-1035_3-57607524-94/wearable-tech-revenue-to-hit-$19b-by-2018/

 

4. Walking energy audio clip

5. Int J Sports Phys Ther. 2013 Apr;8(2):121-8.

Ankle dorsiflexion range of motion influences dynamic balance in individuals with chronic ankle instability.

Basnett CR, Hanish MJ,

 

6. Lower limb biomechanics in individuals with knee osteoarthritis before and after total knee arthroplasty surgery.

http://www.anatomy-physiotherapy.com/component/content/article/28-articles/systems/musculoskeletal/lower-extremity/knee/284-lower-limb-biomechanics-in-individuals-with-knee-osteoarthritis-before-and-after-total-knee-arthroplasty-surgery

7. From a Facebook follower:

Hello there, I’ve been following your stuff for a while now after searching far and wide for solutions to issues I have with my feet/ankles (and the fact I have an interest in what you guys do, I’m going to University in two weeks to study Sports Therapy).
Why I decided to message you now though is because … 

8. Disclaimer

9. National Shoe Fit program and our Payloadz store

10. Online CE October 30th

11. In the media:

Achilles pain and glute control

http://www.runnersworld.com/injury-prevention-recovery/achilles-pain-poor-glute-control-linked

12. J Strength Cond Res. 2013 Oct 11. [Epub ahead of print]

The influence of load and speed on individuals’ movement behavior.

Frost DM, Beach TA, Callaghan JP, McGill SM.

Look at these kids running …  all but one shows poor form, but remember, these kids are still undergoing neurodevelopment and are learning to control their body parts. Remember, the maturation/myelination of the nervous system usually lags behind the development of the musculoskeletal system. 

In the photo, lets first focus on the happy lad in the green shirt. He sure looks like he is having fun, which is what running should be about in kids. If you try to make running a chore for kids you just might lose their love of it in the process. But our point here at The Gait Guys is to teach. So here in this photo are some good teaching points. You should see:

1- the stance phase leg (right leg) is spun out into external rotation. Not too much of a big deal because we do not know if he has finished the normal derotation process of the limb, sometimes this can carry into the puberty years even though for most kids the process is largely completed by his predicted age.

2- The pelvis has drifted laterally in the frontal plane past a perpendicular line up from his foot. This could mean alot of things including gluteus medius or abdominal weakness but the point here is that he has broken through the lateral line (frontal plane) of support up through the hip-pelvis-core chain. This is going to set up what the the left knee (swing leg) is doing and will set up #3.

3. Cross over gait is virtually guaranteed because of the lateral pelvis drift as noted in #2. It is virtually guaranteed as well because the swlng leg knee coming inwards is dictating it. IF the knee is coming inwards toward the midline the thing attached to it , the foot, is going to follow. The swing leg is a pendulum, if you shift the pivot point of the pendulum (in this case to his right) the pendulum will swing to the right. This is a self-perpetuating cycle and it will not correct without strengthening, awareness and drilling positive feedback changes.

4. Dr. Allen’s current thought experiment on Ballasts (see podcast 38) is playing out here with the left arm of this fella. If the pelvis drifts far to the right, the arm will move away from the body to move some of the left side body weight outwards to negate the right shift. This is pure balance physics.  Arm swing most of the time cannot be corrected without correcting the thing that causes the aberrant arm swing, and that is often (but not exclusively) aberrant lower limb and pelvis-hip-core or foot mechanics. There are exceptions, but often if you fix the lower limb and pelvis-hip mechanics  you will see an immediate change in the arm swing. If you force changes in arm swing without fixing the problem (and that is not to say there are not local arm swing etiologies) you may be  driving strength into a compensation pattern that you may not want or like.

5. The girl in the pink tights  … . she might have been modelling the boy in the green shirt. Same issues, same concerns.

6. The form we love the most ? The boy in the dark blue shirt and black shorts on the far right. Great form, no major issues here. We bet he didn’t hear the starters gun go off.

On a side note, the fella in the green shirt with that form he would be a champion race walker. He already has the hip action right, the cross over that is loved in that sport and the arm swing.  Maybe some exposure to an alternate sport is a better solution here ? Although we are always an advocate for correcting flawed biomechanics.

It is often painful for us to watch kids run. We know that much of the things we hate are temporary because of the neuro-developmental process. But sometimes, if kids run too much at a young age, and are pressed into long running miles or cross country at too young an age, these aberrant mechanics can become their new norm. This is the danger of plasticity in the nervous system. Repeated stimulation of a pattern engrains that pattern and the extent of a brain’s plasticity is dependent on the stage of neuro-development and the brain region affected.  When an aberrant running form is allowed to perpetuate into the mid-teenage years, when the majority of the synapses are already formed and neurologic “pruning” and myelination are ramping up, then the repeated exposure to the aberrant pattern can get the myelination. This is the most frustrating thing for us. We would rather see some intervention early on with the creation, strengthening and myelinating of correct motor patterns through skill development training rather than mileage training, rather than discarding the more appropriate synapses that could have, might have, should have, been formed. Our bodies and brain will develop depending on the exposures and demands put upon it. And here is the big key, if you do not clean up someone’s gait aberrancy(s) early on, one should not wonder down the road why they developed flat feet, bunions, early degenerative knees and the like. This is a fairly predictable machine, but you have to try to intervene early to prevent the slings and arrows of outrageous misfortune later on.

Both the brain and the body will adapt to their environment, whether that is an optimal one or a compensatory one. It can myelinate either pathway. Which one will you choose for your kids ?

Shawn and Ivo, The Gait Guys

Do you kick or scrape the inside of your ankle with the other foot ?

We are moving into the final throws of cross country season now and we are seeing the pathologies creep in and the miles go up. Some of you who have been with us for 3 years  have seen this picture but we realized we did not have a blog post on the problem represented by this photo.  This young runner had these scuff marks on the inside of the right lower leg and ankle after a cross country meet.  So what is going on here and what does it tell you ?

Some runners notice that they repeatedly will scuff in the inside ankle or inner calf with the opposite shoe when running. This can happen on both sides but it is more often present unilaterally than bilaterally. 

This problem, typically, but not always represents one of two things:

1- cross over gait (if you are new to our blog in the SEARCH box type in “cross over” and “cross over gait” and be sure to see our 3 part video on the cross over on our youtube channel found here).

2- negative foot progression angle which may or may not be combined with a degree of internal tibial torsion.  Said easier, the runner is “in-toed” or “pigeon toed” but if you have been here with us awhile on The Gait Guys we expect a diagnosis of a higher order so use the former terms, please.

Lets discuss both.

1- Cross over.  When the runner is standing on the right leg, right stance phase of gait, the frontal plane is not properly engaged and the pelvis can drift further over the right foot. This drift to the right will drop the pelvis on the left side. This will alter the pendulum movement of the left leg. Since the global pelvis is moving to the right the left swing leg pendulum moves to the right as well and as it swings past the stance leg it strikes a glancing blow to the inside of the right ankle or calf. This is simple biomechanics and physics. To fix this problem, which is clearly inefficient, one has to determine what is causing the right pelvis drift (there are many causes, the most often thought of cause is a weak gluteus medius on the right but if you have been here with us awhile you will know there are other causes) and then fix the drift. Do not assume it is the gluteus medius all the time, for if it is not, and you employ more glute medius exercises you could be ignoring the source and building a deeper compensation pattern.  Fix the problem, not what you see.

2- Negative foot progression angle and/or internal tibial torsion.  In order to fix this you have to know first if you are dealing with a fixed/rigid anatomic tibial or femoral torsion issue which cannot be fixed or if you are dealing with a flexible progression angle issue. Often, “in-toeing” is accompanied with internal tibial torsion, this is because the knee has to progress forward to keep its tracking mechanics clean, if you correct someone’s foot progression back to neutral and they have internal tibial torsion then you have dragged the patellar tracking outside the normal sagittal progression angle, knee pain will ensue. In fact, the foot progression on the ankle is normal, but the tibia or femur are merely torsioned in a manner that drags the foot inwards with the long bone orientation, again, this is driven by a higher order/demand, to normally track the patella sagittally (forward).  However, if this is a pre-puberty individual you have time because the long bone derotation process is still occuring. Give homework to encourage a good foot tripod and work to strengthen the external hip rotators and encourage sagittal knee tracking mechanics. This is a delicate balancing act, but it can be done, but it is a monster of a project for a blog post because each case is different, variable and always changing depending on the client progress. Remember, you can only encourage more appropriate mechanics and hope that the body will embrace some of the change and encourage some of the de-rotation process to occur from the long bone growth plates. 

The “inside scuff”, to identify its solution you have to know the cause. After all, if it was as easy a fix as “stop doing that” no one would be doing it and we would be out of a job.

Shawn and Ivo …… The Gait Guys 

Podcast 40: Trips, Falls and NFL Shoe Injuries

Today we talk about trip and fall incidence, the NFL shoe injury epidemic and so much more ! Join us today on The Gait Guys podcast !

A. Link to our server:

http://thegaitguys.libsyn.com/podcast-40-trips-falls-and-nfl-shoe-injuries

B. iTunes link:

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

C. Gait Guys online /download store (National Shoe Fit Certification and more !) :

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

D. other web based Gait Guys lectures:

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

* Today’s show notes:

Neuroscience:

 

1. Foramen magnum position in erect ambulation

http://www.sciencedirect.com/science/article/pii/S0047248413001681

 

1b: Scientists Identify Protein Linking Exercise to Brain Health

REDDIT TOP NEWS | OCTOBER 12, 2013
http://pulse.me/s/s2PNS 

2.  More on Cannabinoids

http://www.medicaljane.com/2013/02/13/cannabinoids-breast-milk-do-cannabinoids-play-a-larger-role-in-our-life-than-we-thought/3. 

 

4. TRips and Falls 

http://online.wsj.com/article/SB10001424052702303983904579093560173066446.html

5.  NFL shoes and injuries

http://www.cbssports.com/nfl/writer/pat-kirwan/23931415/big-nfl-ir-numbers-show-more-foot-ankle-injuries-shoes-at-issue

6. From a Blog reader:

Hi guys,

I have been having major leg issues sine my ACL reconstruction  … .

Our DISCLAIMER !, hear it on the podcast. We are NOT your doctor !

7.  From a Blog reader:

Hello, I’m a 19 year old runner trying to get rid of my crossover gait … 

 

8. Another one from a blog reader

Hi, I have a question about externally rotated hip. When i bring my knee up to my chest, my leg turns outward … 

 

9.  Blog

Im really confused with GaitGguys, I follow but this time mixed messages. Recent video showed was varus/lateral boarder push off gait, girl in tennis shoes … 

 

10. National Shoe Fit program: 

http://store.payloadz.com/details/1050149-movies-and-videos-educational-shoe-fit-program-complete-parts-1-3-medical-version.html

A love letter to us !

Dear Gait Guys,

Hi, my name is Paige. I have been working in a sports medicine outpatient clinic for about 2 months now. I love your podcast and recommend it to as many clinicians as possible. I watched your youtube videos on the shuffle gait and have been implementing them into a patient’s home program. They are working great and the patient loves them as well! Just wanted to let you know! I love the videos and hope to take your shoe fit program at some point! You are geniuses and excellent instructors. I’ve learned so much already that we just don’t get enough of in school!
Thanks so much!
Paige

The power to bend bones.

What have we here? Hmmm. This little girl was brought in by her mother because of intermittent knee pain and “collapsing” of the knees while walking, for no apparent reason.

The ankle dorsi flexion (or ankle rocker; see last 2 pictures; we are fully dorsiflexing the ankles)  needs to occur somewhere, how about the knees? Or in this case, the tibia. Wow!

You are looking at a 4 year year with a condition called genu (and tibial) recurvatum. Genu recurvatum is operationally defined as knee hyperextension greater than 5 degrees. The knee is hyperextended, and in this case, the tibia is literally “bent backward”. Look at the 2 pictures of her tibia.

Generally speaking, the tibial plateau usually has a slight posterior inclination (as it does in this case; look carefully at the 1st picture) causing the knee to flex slightly when standing. Sometimes, if it is parallel with the ground and the center of gravity is forward of the knees, the knee will hyperextend (or in this case, the tibia will bend) to compensate.

In this particular case, the tibia has compensated more, rather than the knee itself. The knee joint is stable and there is no ligamentous laxity as of yet. She does not have a neurological disorder, neuromuscular disease or connective tissue disorder. She has congenitally tight calves.

As you can imagine, her step length is abbreviated and ankle rocker is impaired.

So what did we tell her Mom?

• keep her barefoot as much as possible (incidentally, she loves to be barefoot most of the time, gee, go figure!)
• have her walk on her heels (she’s a kid, make a game of it)
• showed her how to do calf stretches
• balance on 1 leg with her eyes open and closed
• keep her out of backless shoes (like the clogs she came in with)
• keep her out of flip flops and sandals where she would have to “scrunch” her toes to keep them on.
• follow back in 3 months to reassess

There you have it. Next time you don’t think Wolff’s (or Davis’s) law* is real, think about this case. Want to know more? Consider taking our National Shoe Fit Program, available by clicking here.

The Gait Guys. Making you gait IQ higher with each post.

*Wolff’s law: Bone will be deposited in areas of stress and removed in areas of strain. or put another way: bone in a healthy person or animal will adapt to the loads under which it is placed

Davis’s law: soft tissue will adapt to the loads that are placed on it

You create your own gait problems.

Just a simple reminder. Most shoes have EVA foam between the hard outsole rubber. EVA foam compresses but it also has memory. If you have a running form issue or a foot type that drives abnormal biomechanics into the shoe then over time the shoe’s EVA foam will break down into that pattern. Not only does this then support the problem, but it enables you to engrain the pattern (which means you are not engraining a cleaner pattern) meaining that every other joint and muscle then assumes that this is the norm and begins to alter their function based on the premise. A sign issue can drive many issues and many other complaints.  This client had a rigid rear foot varus , obviously as you can see by the wear pattern (yes, we gently and lovingly flogged this running for wearing the shoes this long into this pattern) but it was made worse by letting the shoe entrench this pattern so deeply. You see, their rear foot varus was no where nearly as bad as the wear into this shoe. But they continued to wear it and the foam continued to break down further and deeper into this varus wedged pattern. They came into see us for lateral knee pain and a tight IT band that was not responding to foam rolling (we immediately began to whimper and then proceeded to thump our forehead into our desk, repeatedly).  Some things should be obvious, but even we are far from perfect or wise at times.  

Key point, you have heard this here over and over again from us, have 2 or 3 pairs of shoes. Introduce the new shoe into your running repertoire at the 200 mile mark. At that point start rotating your shoes so that you are only a day away from a newer shoe that his not broken down into a faulty pattern and thus deformed EVA foam.  Even by the time the one shoe is dead and done, you have not been in it every run.  You should never kill a shoe to the 500 mile mark and then buy a new shoe. The pattern you have worn into your shoe will suddenly disappear when you put on the new shoe. Injuries occur from repeated events or sudden changes. Reduce your risk and rotated at least 2 pairs of shoes, one newer and one older.  

We talk about alot of these issues, and so much more, in the National Shoe Fit Certification Program. Email us if you think you might be interested.   thegaitguys@gmail.com

And ……when it comes to your feet and shoes, use your head.

Shawn and Ivo, The Gait Guys

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Video: Wow he just lifted,  232 kg, that is 511 pounds !

What is one of our favorite areas to preach about ?  Yes, Ankle dorsiflexion range, or as we often term it, ankle rocker.  There are plenty of activities where we need that critical >90degrees (great than) in order to complete the movement at the appropriate joints.  Depending on the source you reference and the case by case evaluation, typically 110+ degrees are needed at the ankle hinge mortise (tibiotalar joint) in order to keep the motion from being forced elsewhere.  No sport seems to have it as an absolute critical range more than the Clean and Jerk Olympic lift. You can see in this video above, and particularly in this awesome slo-mo video here  that we need that magical range in order to do the lift properly.

What will happen if you try to do it with this critical ankle hinge range ? Well, the foot arch can collapse (pronate) to gain more tibial progression and get that tibia to move forward but this will mean that your tibia will be internally spinning which will drag the knee medially and this will create some serious knee loads and patellar tracking issues, to say the very least. Additionally, this spin can risk the anterior hip joint with issues which we will discuss another time.

The body has some pretty strict parameters when it comes to safe loading responses. And if those parameters are not met, then an alternate pattern must be employed if the motion or load must continue. And alternative loads usually lead to pain or injury.  

Make sure you have enough ankle range, amongst some other critical parameters, if you are going to lift, especially if you are going to lift  heavy.  Can you imagine the impacting load on the foot and the ankle if this fella had stiff ankles with less than 110 degrees ankle dorsiflexion ?  And remember, merely turning out your feet further doesn’t get you around the problem necessarily. It may help a little, but remember, if you are going to turn your feet out (increase your foot progression angle) the knee tracking has to follow that foot angle, and if it does not, then tibiofemoral torsion will increase and meniscal maceration is a foregone guarantee !

Ankle rocker, it is important stuff.  Especially when you are going this big ! But, even if you are doing more remedial squats or Turkish Getups or whatnot.

Shawn and Ivo, The Gait Guys

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Can you see the problem in this runner’s gait ?

You should be able see that they are heel impacting heavy on the outside of the rear foot, and that they are doing so far laterally, more than what is considered normal.  

This is a video of someone with a rear foot varus deformity.

These folks typically have a high arched foot, typically more rigid than flexible, and they are often paired with a forefoot valgus.  

Q: Do you think it might be important as a shoe fitter to know this foot type ?

A: Yes

Q.Should they be put in a shoe with a soft lateral crash zone at the heel ? 

A: No, absolutely not. Why would you want to keep this person deeper and more entrenched on the lateral heel/foot ?!

This foot type has a difficult time progressing off of the lateral foot. The lateral strike pattern and the tendency for the varus rear-foot (inverted)  keeps this person on the lateral aspect of the foot long into midstance.  This eats up time when they should be gradually progressing over to the medial forefoot so that they can get to an effective and efficient medial (big toe) toe off.  This gait type is typically apropulsive, they are not big speed demons and short bursts of acceleration are difficult for these folks much of the time. Combine this person with some torsional issues in  the tibia or femur and you have problems to deal with, including probably challenges for the glutes and patellar tracking dysfunction. What to see some hard, tight IT Bands ?These folks are often the poster child for it. Good luck foam rolling with these clients, they will hate you for recommending it !

They are typically poor pronators so they do not accommodate to uneven terrain well.  Because they are more on the outside of the foot, they may have a greater incidence or risk for inversion sprains. You may choose to add the exercise we presented on Monday (link  here) to help them as best as possible train some improved strength, awareness and motor patterns into their system. In some cases, but only when appropriate, a rear foot post can be used to help them progress more efficiently and safely. 

These foot types typically have dysfunction of the peronei (amongst other things). A weak peroneus longus can lead to a more dorsiflexed first metatarsal compromising the medial foot tripod stability and efficiency during propulsion while also risking compromise to the first metatarsaophalangeal (1st MTP) joint and thus hallux complications.  Additionally, a weak peroneus brevis can enable the rear foot to remain more varus. This muscle helps to invert the rearfoot and subtalar joints. This weakness can play out at terminal swing because the rear foot will not be brought into a more neutral posture prior to the moment of heel/foot strike (it will be left more varus) and then it can also impair mid-to-late midstance when it fires to help evert the lateral column of the foot helping to force the foot roll through to the big toe propulsive phase of terminal stance.  (* children who have these peroneal issues left unaddressed into skeletal maturity are more likely to have these rearfoot varus problems develop into anatomic fixed issues…… form follows function.)

You can see in the video the failed attempt to become propulsive. The client speeds over to the medial foot/big toe at the very last minute but it is largely too late. Sudden and all out pronation at the last minute is also fraught with biomechanical complications.

One must know their foot types. If you do not know what it is you are seeing, AND know how to confirm it on examination you will not get your client in the right shoe or give them the right homework.

* caveat: the mention of Monday’s exercise for this foot type for everyone with Rearfoot varus is not a treatment recommendation for everyone with the foot type. For some people this is the WRONG exercise or it might need modifications. Every case is different. The biomechanics all the way up need to be considered. Medicine is not a compartmentalized art or science. 

Shawn and Ivo, The Gait Guys

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Trade Secret: Proper Calf Raise

We are selling off part of the farm here today in giving this one away.  This is an exercise we prescribe frequently.

When we rise up onto the ball of the foot, most clients and patients tend to come up and either be flush on the forefoot bipod or even a little more onto the lateral aspect of the forefoot. When asked, rarely do we hear that they have a majority of pressure over the medial half of the forefoot. This posturing tendency can lead to inversion sprains. Imagine for a minute a basketball or volleyball player, or any sport for that matter, because most involve the foot leaving the ground and returning to it.  When the foot returns to the ground, if the foot is even a slightly bit inverted (meaning they are even slightly tending towards landing on the outer half of the forefoot) an inversion sprain is at risk. This is particularly so when the lateral gastroc-soleus is weak and the peronei are weak. Forefoot valgus foot types are certainly in the risk category here and so once again we find that knowing your foot types so you can help your clients is need-to-know information.  Back to our jump and to the return to the ground from the jump, you must remember that the metatarsals are shorter and shorter as you move to the lateral foot. This means that if the load is moving laterally because of posterio-lateral compartment weakness as described above, that the sheer design of the shorter lateral metatarsals will continue to press the motion laterally. This is one of the reasons why lateral ankle strains, inversion sprains, are so frequent and repetitive (we have described the other factor in the latency of the peronei after a single inversion sprain in other blog posts here). 

So here we have our calf raise exercise. Squeezing the ball between the ankles on the up (concentric phase) and on the down phase (eccentric) with a nice isometric at the top will force the weight bearing onto the first and second metatarsals (medial forefoot) and drive the lateral compartment to press the motion medially through an isometric instead of depending so much on this compartment to protect the inversion motion through and eccentric.  We find this motor pattern terribly weak in our athletes, especially our jumping sports and certainly after inversion sprains. IF we can provide more strength to hold this medial posture during the return to the ground from a jump we can slow or delay the lateral inversion event risk.  The key to the exercise is to keep the pressure into the ball medially at all times. A wonderful additional benefit to this exercise is that the user will feel the cocontraction of the thigh adductors which further provides a medial stability effort and blends nicely with the lower abdominals.

You can see that in this case we are rehabilitating an achilles tendon repair case on the left leg.

Footprints in the sand. What do they tell us?

They say that sometimes the silences speak volumes. Take a look at these prints and see if you see the following:

• more pressure on the forefoot, right greater than left
• more pressure on the lateral aspects of the forefeet
• an increased progression angle on the right, compared to the left
• judging from the step length, this person either has really long legs or was running
• the heel seems to hit the ground slightly more on the right
• judging from the sole pattern, they are most likely wearing an Inov8 shoe

Or, we can comment on what WAS NOT seen:

• less pressure on the rearfoot, indicating a forefoot strike, or extremely tight posterior compartments
• less pressure on the medial aspects of the forefeet, indicating inefficient push off, since they are not able to get their weight to the medial tripod
• an more normal progression angle on the left, possibly indicating better mechanics there
• this person IS NOT a heel striker, but seems to have a greater range of dorsiflexion available to them on the right, most likely with more ankle rocker
• judging from the sole pattern, they are most likely wearing an Inov8 shoe

Just like in the movie “Swordfish”, John Traviolta’s character comments that “It’s all about perception”.

So, what can we surmise from our deductions?

• less pressure on the rearfoot, indicating a forefoot strike, or extremely tight posterior compartments

this individual may have a loss of ankle rocker

• less pressure on the medial aspects of the forefeet, indicating inefficient push off, since they are not able to get their weight to the medial tripod

we are probably looking for someone who has a fore foot varus deformity. This is often accompanied by increased tibial varum

• n more normal progression angle on the left, possibly indicating better mechanics there

the difference in progression angle may indicate this person has a torsional deformity and/or limited internal rotation of the hips

• this person IS NOT a heel striker, but seems to have a greater range of dorsiflexion available to them on the right, most likely with more ankle rocker

again, look for someone who has impaired ankle rocker, or limited (at least assymetrical) ankle dorsiflexion

Yes, even when we are on vacation, we are looking at gait, because it is everywhere and affects all forms of human life and behavior.

The Gait Guys. Walking in the sand. Looking for the subtle clues. Teaching you in each and every post

If you create it, they may not come....

Range of motion that is…..

We can’t tell you how many times we see an aberrant movement pattern or lack of a range of motion during gait (such as ankle rocker or hip extension), only to test them on the table later to find that they have that range of motion available to them, but for some reason they choose to NOT use it.

 Yes, range of motion IS very important; but if you have the range and don’t use it; it most certainly will be taken away from you and the resources used elsewhere. You need to know what you are doing and how to do it. Then be able to do it over time, time and time again and finally, able to do it with a load (your body weight +).

 Just because you increase someone’s range of motion, does not mean they will be able to incorporate that range of motion into a movement pattern, or compensation pattern for that matter. It is only ¼ of the equation: Range of Motion,  Skill (or proprioception),  endurance (or the proportion of slow twitch muscle) and strength (the proportion of fast twitch muscle). 

 Here is an article that supports this notion, by one of our favorite authors; Dr Stu McGill.

The Gait Guys. Taking you to where the rubber meets the road (because some of you are gluten intolerant and therefore separating the wheat from the chaff is not an option). 

Improvements in Hip Flexibility Do Not Transfer to Mobility in Functional Movement Patterns

Moreside, Janice M.¹; McGill, Stuart M.²

Abstract: Moreside, JM and McGill, SM. Improvements in hip flexibility do not transfer to mobility in functional movement patterns. J Strength Cond Res 27(10): 2635–2643, 2013—The purpose of this study was to analyze the transference of increased passive hip range of motion (ROM) and core endurance to functional movement. Twenty-four healthy young men with limited hip mobility were randomly assigned to 4 intervention groups: group 1, stretching; group 2, stretching plus hip/spine disassociation exercises; group 3, core endurance; and group 4, control. Previous work has documented the large increase in passive ROM and core endurance that was attained over the 6-week interventions, but whether these changes transferred to functional activities was unclear. Four dynamic activities were analyzed before and after the 6-week interventions: active standing hip extension, lunge, a standing twist/reach maneuver, and exercising on an elliptical trainer. A Vicon motion capture system collected body segment kinematics, with hip and lumbar spine angles subsequently calculated in Visual 3D. Repeated measures analyses of variance determined group effects on various hip and spine angles, with paired t-tests on specific pre/post pairs. Despite the large increases in passive hip ROM, there was no evidence of increased hip ROM used during functional movement testing. Similarly, the only significant change in lumbar motion was a reduction in lumbar rotation during the active hip extension maneuver (p < 0.05). These results indicate that changes in passive ROM or core endurance do not automatically transfer to changes in functional movement patterns. This implies that training and rehabilitation programs may benefit from an additional focus on grooving new motor patterns if newfound movement range is to be used.

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It’s that time of the year again….beach cam

With Dr Ivo’s yearly trip to the beach, we have some interesting footage. Today’s winner was this gentleman. We apologize for the shakiness of the camera, as he free handed it for this shot.

Note the following:

• the lack of glute action and the  loss of ankle rocker; his hips NEVER extend past zero. In this case, if they did, he would probably fall forward., due to his abdominal weakness

• To go along with this, we have some premature heel rise, to help him to move forward. As soon as his body mass passes over the foot, the heel comes up.

• Note the forward posture of the head, to attempt to move his center of gravity forward

• Note how his arm swing is only forward. Normally, we like to se the arms move posterior to the body

• He does appear to use his abs to initiate flexion of the thigh. See how he picks up his leg and extends the knee suddenly? This is given away by the acceleration of the leg as he “kicks” it forward.

As you can see, no one is safe from the gait cam. We are everywhere and the army of gait geeks is growing.  Do yourself a favor. Train yourself and others to have ankle rocker, use their glutes to extend their thigh and initiate hip flexion with their abs, rather than the psoas and rectus femoris.

This message is brought to you as a public service by The Gait Guys. Friends don’t let friends have bad biomechanics…