Higher Level Gait Disorders

How deep are you willing to take your gait understanding ?

“In conclusion, these data suggest that the gait and balance deficits in higher level gait disorders (HLGD) mainly result from the lesion or dysfunction of the network linking the primary motor cortex and the mesencephalic locomotor region (MLR), brain regions known to be involved in the control of gait and balance, whereas cognitive and ‘appendicular’ hypokinetic-rigid signs mainly result from deep white matter lesions (DWML) that could be responsible for a dysfunction of the frontal cortico-basal ganglia loops.”

J Neurol. 2014 Jan;261(1):196-206. doi: 10.1007/s00415-013-7174-x. Epub 2013 Nov 8.
High-level gait and balance disorders in the elderly: a midbrain disease?
Demain A

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:


B. iTunes link:


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


D. other web based Gait Guys lectures:

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


* Today’s show notes:


2. Harvard creates cyborg skin
3. Wearable tech
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.

6. 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

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

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

If you do not undestand limb torsions, you are quite possibly screwing up your runners.

You must understand all 3 of these (see below) to understand funky gaits that you see, and to clean up your physical exams with clients. If you are making gait or running form recommendations on this stuff without understanding Torsions you are quite possibly making very bad form recommendations and could be putting forces and torque into foot, ankle, knee or hip that are detrimental. Trust us. We know what we are talking about.

In light of our teleseminar on Chirocredit.com last night we will re-run the 5 Part series on limb Torsions and Versions.

Remember, there are three areas this needs to be considered in:

1. torsion of the talus

2. tibial torsion

3. femoral torsion

here is the link to our old post on this topic, part 1a


Shawn and Ivo

The “Top-End” Peroneal Walk Foot Skill: Another Restoration Foot Trick by The Gait Guys

Have stability problems in your ankles ? Lots of people do !
Here is a brief video of a simple, but difficult, functional exercise to strengthen the peroneal muscles in full plantar flexion (we will give more detailed tricks and techniques away on the Foot-Ankle DVD exercise series, once we get some time to get to it !). The key here is to not let the heel drop during single fore-foot loading and to keep the ankle pressing inwards as if to try and touch the ankles together medially …..if you feel the heel drop on the single foot loaded side (or you can feel the calf is weaker or if you feel strain to keep the inward press of the ankle) then it might be more than the peronei, it could be the combined peroneal-gastrocsoleus complex. The key to the assessment and home work is to make sure that the heel always stays in “top-end” heel rise plantarflexion. But you have to strongly consider the peronei just as seriously. Studies show that even single event sprains let alone chronic ankle sprains create serious incompetence of the peronei. Most people do not notice this because they never assess the ability to hold the foot in full heel rise (plantarflexion) while creating a valgus load (created by the peronei mostly, a less amount from the lateral calf) at the ankle. This is why repetitive sprains occur. The true key to recovery is to be able to walk on the foot in this heel-up “top-end” position while in ankle eversion (ankles squeezed together) as you see in this video. This is something we do with all of our basketball and jumping sports athletes and it is critical in our dancers of all kinds. And if they cannot do the walking skill or if they feel weakness then we keep it static and put a densely rolled towel or a small air filled ball between the ankles and have them do slow calf raises and descents while squeezing the towel-ball with all their ability. This will create a nice burn in the peroneal muscles after just a few repetitions. The user will also quickly become acutely aware of their old tendency to roll to the outside of the foot and ankle because of this lack of awareness and strength of those laterally placed ankle evertors - the peronei. It is critical to note that If you return to the ground from a jump and cannot FIRST load the forefoot squarely and then, and only then, control the rate of ankle inversion and neutral heel drop (ankle dorsiflexion) then you should not be shocked at chronic repetitive ankle sprains. Remember, the metatarsals and toes are shorter as we move away from the big toe, so there is already a huge risk and tendency to roll to the outside of the foot through ankle inversion. Hence why ankle sprains are so common. We call this “top end” peroneal strength but for it to be effectively implemented one must have sufficient top end calf strength as well, you cannot have sound loading mechanics without both.
It is not as easy as it appears in this video. We encourage you to give this a try and we bet that 1 out of every 2 people who try it will notice “top end” weakness felt either in the peronei and/or in the calf via inability to keep the heel in “top-end”. Oh, and do not think that you can simply correct this by more calf work, not if the peronei are involved, which they usually are.
One more trick by The Gait Guys………bet you cannot wait for the foot dvd huh !? Ya, it has only been on our list for 3 years now !
 We talk more about this kind of stuff on our National Shoe Fit Certification program.
Email us if you are interested thegaitguys@gmail.com


A Window into the Glutes: Anatomy lesson for the day.


A rather literal statement for a rather literal picture. Taken from the Human Body Exhibit at the Denver Museum of Science, this picture offers us a glimpse into, or in this case through, one of our favorite muscle groups. This group that we see here, is probably our second favorite group. They are often called the “deep six” and are the deep hip external rotators. If you count, you will notice there are only five….one remains unseen the obturator internus. More on that later.


See the linear white lines on the right of the window? That’ s the two portions of the sciatic nerve. Notice how it runs under the muscle at the top and over the others? The muscle it runs under is the famous piriformis. When this muscle gets tight, it can impinge the sciatic nerve, causing pain down the leg (known as sciatica). This represents one of many causes of pain radiating down the leg.


The next muscle south is the gemelli superior, then the obturator externus, gemelli inferior, and quadratus femoris. The sixth of the deep six is the obturator internus, which runs from the inside of the pelvis on the obtrobturator foramen (those huge “eyes” you see in an x ray when looking at a pelvis from the front) to a similar place on the femur.


A few observations you should make.


  • when someone chews your butt off, or chews you a new one, this picture gives it a whole new meaning

  • the sciatic nerve runs under the piriformis
  • The top (superior) five muscles have a tendonous insertion to the femur that you can see as a whitish area on the left

  • the last (or most inferior muscle) has a muscular insertion to the femur (which is a reddish area on the left)
  • the positioning of these muscles allows them to be external rotators of the femur when the foot is in the air

  • when the foot is planted, they become external rotators of the pelvis or can act to slow internal rotation of the femur during stance phase
  • as you proceed caudally, the muscles become stronger adductors of the thigh


We will see this post as a reference for some future posts on this most fascinating muscle groups. Until then, study up!


The Gait Guys. Uber Foot Geeks. Join us in our mission to educate the world on the importance of understanding human motion and its impact on translating us forward in the gravitational plane.



all material copyright 2013 The Gait Guys/ The Homunculus Group. All rights reserved

A tangled tail of two, 2-joint muscles: Lombard’s Paradox

Two years ago we wrote this little piece on these 2 two joint muscles.  Their companionship mentally came up during the sorting out of a strange client case so we felt it was good karma to share it again.   This one may make your head spin.

We do not know where this write up came from and how much was our original material and how much was someone else’s. It was found on an old computer of long ago. If you can find the reference we would love to give it credit.  We do know that we added some stuff to this but we don’t even know what parts were ours !  Regardless, there is a brain twister here worth juggling in your heads.  Some of it we know is far reaching and even marginally incorrect, but we like mental aerobics to take it for what its worth. There is value in thinking about things this way. Lets start with this thought……..

When you are sitting the rectus femoris (a quad muscle) is “theoretically” shortened at the hip because the hip is in flexion. It also  crosses the bent knee in the front at it blends with the patellar tendon, thus it is “theoretically” lengthened at the knee.  When we stand up, the hip extends and the knee extends, making the R. Femoris “theoretically” lengthen at the hip and shorten at the knee.  Thus, it bodes the question…….did the R. Femoris even change length at all ? Did a concentric event occur at one end and an eccentric contractile event occur at the other ? Is that even possible ? And, the hamstrings kind of go through the same phenomenon on the other side of the knee and hip so you possibly have a very complex dialogue across the front and the back of the knee and hip during movement. And for every angle of flexion or extension change around the knee or hip both the quads and the hamstrings have this sliding scale of change they have to play, it should be a perfect give and take phenomenon. And when orchestrated cleanly the joints do not see impairment. This is part of the uniqueness of “two joint” muscles.  However, think about how a short quadriceps, a very common clinical finding, will impair this orchestra. Like an instrument out of tune the orchestration is in flux and alternative strategies ensue. How will the function at the knee be changed by this short quadriceps ? How will hip extension be impaired ?  How will the hamstring alter its function ? What will the consequences be ? What alternative motor patterns will be deployed ? And if you are just doing your gait analysis without a clinical examination what will you see as their compensation ? Now that your head is buzzing, onto Lombard’s paradox with more in depth thought on this topic.

Warren Plimpton Lombard (1855-1939) sought to explain why the quadriceps and hamstring muscles contracted simultaneously during the sit-to-stand motion.  He noted that the rectus femoris and the hamstrings are antagonistic, and this coactivation is known as Lombard’s paradox.

The paradox is classically explained by noting the relative moment arms of the hamstrings and rectus femoris at either the hip or the knee, and their effects on the magnitude of the moments produced by either muscle group at each of the two joints.

By virtue of the fact that muscles cannot develop different amounts of force in their different parts, the paradox develops.  The hamstrings cannot selectively extend the hip without imparting an equal force at the knee. Thus, the only way for hip extension and knee extension to occur simultaneously in the act of standing (or eccentrically in the act of sitting) is for the net moment to be an extensor moment at both the hip and knee joints. Lombard suggested three necessary conditions for such paradoxical co-contraction:

  • the lever arm of the muscle must be greater at its extensor end
  • a two-joint muscle must exist with opposite function
  • the muscle must have sufficient leverage so as to use the passive tendon properties of the other muscle

In 1989, Felix Zajac & co-workers pointed out that the role of muscles, particularly two-joint muscles, was much more complex than has traditionally been assumed. For example, in certain situations, the gastrocnemius could act as a knee extensor. It is clear now that the direction in which a joint is accelerated depends on the dynamic state of all body segments, making it difficult to predict the effect of an individual muscle contraction without extensive and accurate biomechanical models (Zajac et al, 2003).

 In fact, back to the gastrocnemius another 2+ joint muscle (crosses knee, mortise and subtalar joints), we all typically think of it as a “push off” muscle.  It causes the heel to rise and accelerates push off in gait and running. But, when the foot is fixed on the ground the insertion is more stable and thus the contraction, because the origin is above the posterior joint line, can pull the femoral condyles into a posterior shear vector. It thus, like the hamstrings, needs to be adequately trained in a ACL or post-operative ACL, deficient knee to help reduce the anterior shear of normal joint loading. It is vital to note, that when ankle rocker is less than 90  degrees (less than 90 degrees of ankle dorsiflexion is available), knee hyperextension is a viable strategy to progress forward over the ankle in the sagittal plane.  But in this scenario, the posterior shear capabilites of the gastrocnemius are brought to the front of the line as a frequent strategy.  And not a good one for the menisci we should mention.

Just some random thoughts for you today. We used to play such mental games during my orthopedic residency. The “what would happen if” scenarios. They stimulate thought, dialogue and debate and get the brain thinking more globally.  We hope you enjoyed the circus show today !

Shawn and Ivo…….. the gait guys

Andrews J G (1982)  On the relationship between resultant joint torques and muscular activity  Med Sci Sports Exerc  14: 361-367.

Andrews J G (1985)  A general method for determining the functional role of a muscle  J Biomech Eng  107: 348-353.

Bobbert MF, van Soest AJ (2000) Two-joint muscles offer the solution - but what was the problem? Motor Control 4: 48-52 & 97-116.

Gregor, R.J., Cavanagh, P.R., & LaFortune, M. (1985). Knee flexor moments during propulsion in cycling—a creative solution to Lombard’s Paradox. Journal of Biomechanics, 18, 307-16 .

Ingen-Schenau GJv (1989) From rotation to translation: constraints on multi-joint movement and the unique action of bi-articular muscles. Hum. Mov. Sci. 8:301-37.

Lombard, W.P., & Abbott, F.M. (1907). The mechanical effects produced by the contraction of individual muscles of the thigh of the frog. American Journal of Physiology, 20, 1-60.

Mansour J M & Pereira J M (1987)  Quantitative functional anatomy of the lower limb with application to human gait  J Biomech  20: 51-58.

Park S, Krebs DE, Mann RW (1999) Hip muscle co-contraction: evidence from concurrent in vivo pressure measurement and force estimation. Gait & Posture 10: 211-222.

Rasch, P.J., & Burke, R.K. (1978). Kinesiology and applied anatomy. (6th ed.). Philadelphia: Lea & Febiger.

Visser JJ, Hoogkamer JE, Bobbert MF & Huijing PA (1990) Length and Moment Arm of Human Leg Muscles as a Function of Knee and Hip Angles. Eur. J Appl Physiol 61: 453-460.

Zajac FE & Gordon MF (1989) Determining muscle’s force and action in multi-articular movement  Exerc Sport Sci Revs  17: 187-230.

Zajac FE, Neptune RR, Kautz SA (2003) Biomechanics and muscle coordination of human walking - Part II: Lessons from
dynamical simulations and clinical implications, Gait & Posure 17 (1): 1-17.

The Coffee Walkers: Why coffee should come in a sippy cup. A tangent article on gait concepts.

It has been a year since we posted this one on our blog, one of our 900 articles written by your’s truly.  And as we were working on another new post while gulping our newest bio-hack (bulletproof coffee= micotoxin free coffee beans + grass fed butter and MCT oil all blended to a foamy delicious brain drink courtesy of our friend Dave Asprey over at the Bulletproofexec) we felt that our article wouldn’t be at the level we wanted it so we remembered “The Coffee Walkers” post we did 12 months ago.  Here it is in its original caffeinated form. Enjoy.


It sounds like some creepy Steven King inspired blog post today (reminds us of the Tommy Knockers). However, the truth of the matter is that this is a gait blog post on walking.

Why is it so hard to walk with a cup of “joe” or a coffee mug of anything liquid for that matter ? It is all about physics and wave frequency.

In a neat little article written by Natalie Wolchover for CNBC.com she says,

“New research shows that “the properties of mugs, legs and liquid conspire to cause spills, most often at some point between your seventh and tenth step. So says a pair of fluid physicists at the University of California at Santa Barbara.”

This is a physics problem actually. It is one of frequencies to be precise. Apparently the human stride has almost exactly the right frequency and amplitude to drive the natural oscillations of a liquid when it is in a classic shaped and sized coffee mug. The frequency of the liquid sloshing to and fro in your mug has the same frequency as your gait. So, when you are walking with your mug-of-Joe there is an additive effect of the two frequencies and apparently the more steps that are taken the effect eventually summates until the lip of the mug is exceeded. Stopping or slowing down once the ride is underway and the summation effect is changed, but not necessarily reversed. A sudden change in the frequency, such as you suddenly stopping, slowing or speeding up, can abruptly change the effect on the mug however the fluid within the vessel is not changed at the same rate and thus it can breach the edge of the mug.

According Wolchover, of one of the linked articles,

“Coffee drinkers often attempt to walk quickly with their cups, as if they might manage to reach their destination before their sloshing java waves reach a critical height. This method is scientifically flawed. It turns out that the faster you walk, the closer your gait comes to the natural sloshing frequency of coffee. To avoid driving the oscillations that lead to a spillage, walk slowly.” The other valid suggestions were to watch the mug and to accelerate slowly.

We take the easier route. Maybe we are smarter, maybe lazier, and maybe just tired of always analyzing things … . . we choose a container with a damn lid. Can you say “Einstein-ian” ? We don’t like coffee sloshing on our clothes or rugs.

Shawn and Ivo ………… jacked up on Joe.  Get you never thought we would be able to turn coffee-talk into a gait article huh ?  And you thought we would run out of gait stuff to talk about !

Article links that provided the inspiration for today’s post, and that we referenced.