Arm swing and instability. To train or not to train... Should we do it?

We have long talked about arm swing and whether to change it, encourage it or just observe it. It appears to be an indicator of potential instability as well as a portent for more dire neurological problems (Alzheimers, Parkinson's)

This study looks at altered arm swing in kids with CP; how it is an indicator that there is a problem and how it can profoundly effect their gait and stability. Cerebral palsy may be an extreme case, but how does it differ REALLY (other than severity) from someone who has a mild neurological impairment, such as movement patterning disorders, that we see each and every day in our friends, family, clients and patients? Try and think out of the box and investigate the implications.

"Observational research suggests that in children with cerebral palsy, the altered arm swing is linked to instability during walking. Therefore, the current study investigates whether children with cerebral palsy use their arms more than typically developing children, to enhance gait stability. Evidence also suggests an influence of walking speed on gait stability. Moreover, previous research highlighted a link between walking speed and arm swing. Hence, the experiment aimed to explore differences between typically developing children and children with cerebral palsy taking into account the combined influence of restricting arm swing and increasing walking speed on gait stability. Spatiotemporal gait characteristics, trunk movement parameters and margins of stability were obtained using three dimensional gait analysis to assess gait stability of 26 children with cerebral palsy and 24 typically developing children. Four walking conditions were evaluated: (i) free arm swing and preferred walking speed; (ii) restricted arm swing and preferred walking speed; (iii) free arm swing and high walking speed; and (iv) restricted arm swing and high walking speed. Double support time and trunk acceleration variability increased more when arm swing was restricted in children with bilateral cerebral palsy compared to typically developing children and children with unilateral cerebral palsy. Trunk sway velocity increased more when walking speed was increased in children with unilateral cerebral palsy compared to children with bilateral cerebral palsy and typically developing children and in children with bilateral cerebral palsy compared to typically developing children. Trunk sway velocity increased more when both arm swing was restricted and walking speed was increased in children with bilateral cerebral palsy compared to typically developing children. It is proposed that facilitating arm swing during gait rehabilitation can improve gait stability and decrease trunk movements in children with cerebral palsy. The current results thereby partly support the suggestion that facilitating arm swing in specific situations possibly enhances safety and reduces the risk of falling in children with cerebral palsy."

Front Hum Neurosci. 2016 Jul 15;10:354. doi: 10.3389/fnhum.2016.00354. eCollection 2016.
Restricted Arm Swing Affects Gait Stability and Increased Walking Speed Alters Trunk Movements in Children with Cerebral Palsy.
Delabastita T, Desloovere K, Meyns P.

link to FREE FULL TEXT: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4945643/

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How well do you understand stance phase mechanics?

Here is a recent question we fielded and thought it would make a great post. 

Question/Comment: I’m slightly confused about closed chain hip motion in the stance leg.


Maybe if I explain what my thought process is you can correct me.  Lets use
left stance phase with the right leg swinging through.

After right mid-swing, the pelvis will be rotating towards the left.  The
motion of the pelvis on the left femur would be relative femur internal
rotation.  I understand that the right leg is externally rotating
(supinating) and that normal open chain kinematics of hip extension is
coupled with external rotation.  But if the pelvis is moving towards the
left AND the left femur externally rotates, wouldn’t that create too much
rotation?  So what I’m saying is that a pelvis that is oriented to the left
with a left femur that externally rotates creates an odd motion in my head
(which may be where the problem lies).  If you’ve ever seen a western where
the gun slingers do that weird walk to a shoot out…that’s what an
externally rotating femur during terminal stance looks like to me.

I’ve discussed this with other clinicians.  Some are in agreement with me,
some think it’s externally rotating, and some don’t know what I’m talking
about.  In my patients I also see a loss of hip IR more than hip ER.  These
patients that lose hip IR seem to have more difficulty in terminal
stance/toe-off phase more than the ones that lose hip ER.

If you could help me understand these kinematics and clear this up for me I
would greatly appreciate it.

Thank you, A

our reply: 

Taking your example with the L leg in stance:
When the L heel contacts the ground, the friction of the ground (hopefully) slow the calcaneus and the talus slide anteriorly on the calcaneus. 

Because of the shape of the calcaneal facets, the talus plantar flexes, adducts and everts. This sets the stage for pronation to occur: the calcaneus everts and the lower leg internally rotates, with the thigh following. The right side of the pelvis is moving to the L (counter clockwise rotation). This should occur (ideally) until midstance. At midstance, the opposite ® foot begins to enter swing phase; this should initiate supination of the stance phase leg (L). At this point, the L foot should be beginning to supinate the the leg and thigh beginning external rotation. It (thigh and leg) should reach maximal external rotation at toe off (maximal counter clockwise rotation of the pelvis) and remain in external rotation until heel strike/initial contact on the L side again. At this point, the pelvis begins clockwise rotation.

It is necessary for the thigh and leg to externally rotate while the pelvis is rotating counter clockwise, because of the constraints of the iliofemoral, pubeofemoral and ishiofemoal ligaments.

We too often see a loss of internal rotation of the hip in symptomatic populations more often than external rotation.

We hope this clarifies things for you.

Thank you again for the question and taking the time to write.

The Gait Guys

Does this guy have a short leg or what? How good are your eyes?

One again, we had the gait cam, investigating gait on the east coast. What do we see in this gent?

  • heel strike on out side of left foot with increased progression angle

he appears to be stabilizing the left side during stance phase. notice the upper torso shift to the left during left stance phase

  • abbreviated arm swing on right

note that ankle rocker is adequate on the left

  • body lean to right on right stance phase

gluteus medius weakness on right? short leg on right?

Good.

  • Did you also notice the loss of ankle rocker on the right, compared to the left? This results in less hip extension on that side as well.
  • He flexes his right thigh less than his right during pre swing and swing

external obliques should be firing to initiate hip flexion, perpetuated by the psoas, iliacus and rectus femoris. This does not appear to be happening.

All of this is great BUT nothing like being able to actually examine your patients is there? You can see how gait analysis can tell us many things, but they need to be confirmed by a physical exam.

The Gait Guys. Educating (and hopefully enlightening) with each post. Keep your eyes open and your thinking from the ground up : )



Got Arm Swing?

We have written many times about arm swing. Click here for some of our posts here on Tumblr.

Here we are again at the beach. Look at the beautiful difference in arm swing from side to side in the guy carrying the bag. Makes you want to tell him to use a backpack, eh?

Never mind what it does to his gait

  • decreased arm swing on the carrying side
  • increased step length on the left side
  • increased thigh flexion of the left side
  • increased body lean and head tilt to right side (Take a look at this paper)

think about the increased metabolic cost. Think about what this  type of input (increased amplitude of movement unilaterally) is doing to your cortex!

keep your movements symmetrical, folks!

The Gait Guys

A profound loss of hip extension…

While sitting on the beach, our mind never rests. Even when on vacation we continue to watch how people move.

Luckily today, I had the gait cam (Dr Allen is holding down the Gait Guys Fort), so live from Sunset Beach, it’s Sunday night. See of you can see what I saw.

Sitting with my wife and watching the kids dig in the sand, this gal with the flexed posture caught my eye.

Why is she so flexed forward? The profound loss of hip extension made it impossible for her to stand up straight! It was difficult to say if she has bilateral hip osteoarthritis, or possible bilateral THR’s (total hip replacements), maybe just really tight hip flexors, painful bunions that do not like toe off, or even all of the above. She may have a leg length discrepancy, as she leans to the left on left stance phase; of course she could have weak hip abductors on the left. It does not appear she has good control of her core.

What do we see?

  • flexion at the waist
  • loss of hip extension
  • body lean to left at left midstance
  • shortened step length
  • loss of ankle rocker
  • premature heel rise
  • decreased arm swing (she is carrying something in her left hand)

No one is safe from the gait cam! Stay tuned for more beach footage this week!

We remain, The Gait Guys, even on vacation.

This is part 2 of a 2 part post; with the video from the case previously discussed

please note the following in the video:

  • body lean to left during left stance phase (to clear right longer leg)
  • circumduction of right lower extremity  (to clear right longer leg)
  • lack of arm swing bilaterally (cortical involvement)
  • patient looking down while walking (decomposition of gait)
  • shortened step length (decomposition of gait)
  • increased tibial varum bilaterally

ASSESSMENT:  This patient’s short leg and internal tibial torsion impediments to her full recovery. She has increased tibial varum noted which is complicating the picture. This is causing pathomechanics and an abductory moment not only at the knee but also in the lumbar, thoracic and cervical spines.

WHAT DID WE DO?:                    

  • We attempted to do the one leg standing exercise. She needed to hold on and did not feel stable on the left hip while performing this.  This is probably more of confidence rather than ability issue. 
  • We gave her the stand/sit exercise to try to improve gluteal recruitment.
  • We also gave her the lift/spread/reach exercise to attempt to strengthen her feet.
  • A full-length 5 mm lift was cut for the left shoe  She felt more stable when walking on this.
  • She was treated with IC, PIR and manipulative therapy and neuromuscular stim of the knee as well as left hip area above, below and at the joint line of the knee as well as gluteus medius and minimus.   
  • We may need to consider building a more aggressive orthotic with a forefoot varus post depending upon her progress and response to care  

 The Gait Guys. Making it real, each and every post here on the blog.

special thanks to SZ for allowing us to publish her case, so others can learn

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Wow! What would you do?

This is part 1 of a 2 part post. Look for the other one a few minutes after this one with a video up top for the conclusion

PRESENTING PROBLEM: This 54 YO female patient presents with with left sided knee pain.  She had a total knee replacement (TKR) done in 2011.  She’s had a significant amount of discomfort on the medial aspect of the knee since then. She had an MRI of the hip done thinking the problem was there, and found nothing.   She is walking with a bad limp, left leg is half inch shorter than the right.  Pain is worse at night, changes with weather. 

She has knee pain on the lateral aspect (points to tibial plateau and joint line) with swelling that goes down to the ankle left side.  She has been wearing a “Good Feet” OTC orthotic on the left side which she states helps quite a bit.

Generally speaking, stretching and analgesics make the discomfort better.    Ibuprofen 400 mg. b.i.d. can take the edge off  Soft sided brace (neoprene sleeve) makes a difference as well. The hard sided brace gives her difficulty.

WORK HISTORY: She works for a preschool.  Her job involves standing and getting up and down a lot.  

FAMILY HISTORY:  She has left sided lid ptosis, this evidently is familial.  

PHYSICAL EXAM:  She stood 5’ 1” and weighed approx. 150 pounds.

Viewing the knees bi-lat., the left knee is markedly externally rotated.

She does have a left short leg; tibial and femoral.  She has bilateral tibial torsion (look at the tibial tuberosities and drop a line straight down; it should pass through the 2nd metatarsal head) and marked internal tibial torsion on the left side (>60 degrees) with femoral retrotorsion (less than 8 degree angle of femoral head with the shaft) on this side.  There is no rotation of the thigh or leg past zero degrees midline. .  She had 10 degrees of tibial varum on the left hand side.  Her Q-angle is 10 degrees on that side.  There is plantar flexion inversion of the foot.  Left lower extremity has less sensation secondary to the her TKR  surgery.

Gait evaluation reveals a fair amount of midfoot pronation noted on the left hand side in addition to an intoed gait.  She has to lean her body over to the left to get the right leg to clear.

Some mild weakness noted of hip abduction musculature left hand side gluteus medius, middle and anterior fibers. Knee stability tests were negative.

Neurologically, otherwise, she had full integrity with respect to sensation, motor strength and deep tendon reflexes in the upper and lower extremities.

Please see part 2 of this post for additional info including our assessment and what WE did.

 The Gait Guys. Making it real, each and every post here on the blog.

special thanks to SZ for allowing us to publish her case, so others can learn

Podcast 69: Advanced Arm Swing Concepts, Compensation Patterns and more

Plus: Foot Arch Pathomechanics, Knee Pivot Shift and Sesamoiditis and more !

A. Link to our server: 

http://traffic.libsyn.com/thegaitguys/pod_70ff.mp3

Direct Download: http://thegaitguys.libsyn.com/podcast-70

Permalink: 

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:

1. “Compensation depends on the interplay of multiple factors: The availability of a compensatory response, the cost of compensation, and the stability of the system being perturbed.”
What happens when we change the length of one leg? How do we compensate? Here is a look at the short term consequences of a newly acquired leg length difference.
http://www.ncbi.nlm.nih.gov/pubmed/24857934
2. Medial Longitudinal Arch Mechanics Before and After a 45 Minute Run
http://www.japmaonline.org/doi/abs/10.7547/12-106.1

3. Several months ago we talked about the pivot-shift phenomenon. It is frequently missed clinically because it can be a tricky hands on assessment of the knee joint. In this article “ACL-deficient patients adopted the … .* Remember: what you see in their gait is not their problem, it is their strategy around their problem.
http://www.clinbiomech.com/article/S0268-0033(10)00264-0/abstract

4.Do you know the difference between a forefoot supinatus and a forefoot varus?
"A forefoot varus differs from forefoot supinatus in that a forefoot varus is a congenital osseous deformity that induces subtalar joint pronation, whereas forefoot supinatus is acquired and develops because of subtalar joint pronation. ”
http://www.ncbi.nlm.nih.gov/pubmed/24980930

5. Pubmed abstract link: http://www.ncbi.nlm.nih.gov/pubmed/24865637
Gait Posture. 2014 Jun;40(2):321-6. Epub 2014 May 6.
Arm swing in human walking: What is their drive?
Goudriaan M, Jonkers I, van Dieen JH, Bruijn SM

6. This is Your Brain On Guitar
http://www.the-open-mind.com/this-is-your-brain-on-guitar/

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So you want to do a Gait Analysis: Part 4

This is the 4th in a multi part series. If you missed part 1, click here. For part 2, click here, part 3, click here

These are the basics, folks. We hope this is a review for many.

A quick review of the walking gait cycle components:

There are two phases of gait: stance and swing

Stance consists of:

  • Initial contact
  • Loading response
  • Midstance
  • Terminal stance
  • Pre-swing

Swing consists of:

  • initial (early) swing
  • mid swing
  • terminal (late) swing

today, lets explore Terminal stance

Terminal stance is one of the last stages of stance phase. Following midstance, where maximal pronation should be occurring, the stance phase foot should now begin supinating, initiated by the the opposite foot in swing phase moving forward of the center of gravity. 

Lets look at what is happening here at the major anatomical areas:

Foot

  • Supination begins from the opposite, swing phase leg (see above)
  •  the calcaneus inverts to neutral
  •  the center of gravity of the foot raises from its lowest point at midstance
  • The lower leg should begin externally rotating (as it follows the talus)
  • The thigh should follow the lower leg and should also be externally rotating; sometimes to a greater extent due to the shape and size of the medial condyle of the femur (which is larger than the lateral)
  • these actions are perpetuated by the gluteus maximus and posterior fibers of the gluteus medius, as well as posterior compartment of the lower leg including the flexor digitorum longus, flexor hallucis longus, peroneus longus and tibialis posterior
Ankle
  • The ankle should be 5 degrees dorsiflexed and in ankle rocker
  • the calcaneocuboid locking mechanism should be engaging to assist the peroneus longus in getting the head of the 1st metatarsal to the ground

Knee

  • near or at full extension. This is perpetuated by the quadriceps and biceps femoris, contracting concentrically and attenuated by the semi membranosis and tendonosis. The popliteus contracts eccentrically as soon as the knee passes midstance to keep the rates of external rotation of the tibia and femur in congruence.

Hip

  • The hip should be extending to 10 degrees.

Can you picture what is happening? Try and visualize these motions in your mind. Can you understand why you need to know what is going on at each phase to be able to identify problems? If you don’t know what normal looks like, you will have a tougher time figuring out what is abnormal.

Ivo and Shawn. Gait and foot geeks extraordinaire. Helping you to build a better foundation to put all this stuff you are learning on.

pictured used with permission from Foot Orthoses and Other Conservative Forms of Foot Care

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So a patient presents to your office with a recent history of a L total knee replacement 8 weeks ago AND a recent history of a resurgence of low back pain, supra iliac area on the L side. Hmmmm. Hope the flags went up for you too!

His global lumbar ROM’s were 70/90 flexion with low back discomfort at the lumbo sacral junction, 20/30 extension with lumbosacral discomfort, left lateral bending 10 degrees with increased pain (reproduction); right lateral bending 20 degrees with a pulling sensation on the right. Extension and axial compression of the lumbar spine in left lateral bending reproduced his pain.

Neurologically he had an absent patellar reflex on the left, with diminished sensation over the knee medially and laterally. Muscle strength 5/5 in LE; sl impaired balance in Left single leg standing. There was incomplete extension of the left knee, being at 5 degrees flexion (right side was zero).

He has a right sided leg length deficiency (or a left sided excess!) of 5 mm. Take a look at the tibial lengths in the 1st 3 pictures. See how the left is longer? In the next shot, do you see how the knee cannot completely extend? Can you imagine that the discrepancy would probably be larger if it did?

Now look at the x rays. We drew a line across from the non surgical leg to make things clearer.

Now, think about the mechanics of a longer leg. That leg will usually pronate more in an attempt to shorten the leg, and the opposite side will supinate to attempt to lengthen. Can you see how this would cause clockwise pelvic rotation (in addition to anterior pelvic rotation)? Can you see this patients in the view of the knees from the top? Do you understand that the lumbar spine has very limited rotation (about 5-10 degrees, with more movement superiorly (1)  ). Does it make sense that the increased range of motion could effect the disc and facet joints and increase the patients low back pain?

So, how do we fix it? Have you seen the movie “Gattica”? Hmmm….A bit extreme. How about a full length 3mm sole lift to start, along with specific joint manipulation to restore normal motion and some acupuncture to reduce inflammation? We say that is a good start.

The Gait Guys. Increasing your gait literacy with each and every post. If you liked this post, please send it to someone else for them to enjoy and learn. 

(1) Three-Dimensional In Vivo Measurement of Lumbar Spine Segmental Motion Ruth S. Ochia, PhD, Nozomu Inoue, MD, PhD, Susan M. Renner, MS, Eric P. Lorenz, MS, Tae-Hong Lim, PhD, Gunnar B. Andersson, J. MD, PhD, Howard S. An, MD Spine. 2006;31(15):2073-2078.

Can you see it? 
 Here we are again. We have looked at this picture before; once about  head tilt , and another about  flip flops  and form. 
 Take a good look at this picture and what is different about the child in blue all the way to the right and all the others with the exception of the boy in pink, that we really cannot see? 
 Can you see it? No, we don’t mean the flip flops (but if you caught that all the boys were in sneakers and all the girls are in flip flops, you are good!) 
 How about looking at arm swing? Remember  this post  on arm swing and crossover gait, with the simple cue for correction? All of the children EXCEPT the boy in blue, are drawing their arms ACROSS their body (ie: flexion, internal rotation and adduction). Take a look at their legs. Yep, crossover gait (flexion, internal rotation and adduction). Little boy blues arms are going relatively straight and going in the saggital plane, where the others are going in the coronal plane. 
 We are not saying that blue does not have some gait challenges, like his torso shift to the left (or pelvic drift to the right), most likely do to gluteus medius weakness or inappropriate firing of the gluteus medius on the left stance phase leg; or his head tilt to the right, which most likely represents a compensation for the right pelvic drift and left body lean. 
 Arm swing. A very important clue to the puzzle we call gait and compensation. It is more prevalent than you think, and, in some cases, easily corrected with a simple cue. 

  The Gait Guys. Making it real and pertinent, in each and every post.

Can you see it?

Here we are again. We have looked at this picture before; once about head tilt, and another about flip flops and form.

Take a good look at this picture and what is different about the child in blue all the way to the right and all the others with the exception of the boy in pink, that we really cannot see?

Can you see it? No, we don’t mean the flip flops (but if you caught that all the boys were in sneakers and all the girls are in flip flops, you are good!)

How about looking at arm swing? Remember this post on arm swing and crossover gait, with the simple cue for correction? All of the children EXCEPT the boy in blue, are drawing their arms ACROSS their body (ie: flexion, internal rotation and adduction). Take a look at their legs. Yep, crossover gait (flexion, internal rotation and adduction). Little boy blues arms are going relatively straight and going in the saggital plane, where the others are going in the coronal plane.

We are not saying that blue does not have some gait challenges, like his torso shift to the left (or pelvic drift to the right), most likely do to gluteus medius weakness or inappropriate firing of the gluteus medius on the left stance phase leg; or his head tilt to the right, which most likely represents a compensation for the right pelvic drift and left body lean.

Arm swing. A very important clue to the puzzle we call gait and compensation. It is more prevalent than you think, and, in some cases, easily corrected with a simple cue.

The Gait Guys. Making it real and pertinent, in each and every post.

Correcting a cross over gait with arm swing? Is it really THAT easy? Sometimes, yes!

We noticed this patient had a cross over gait while running (1st few seconds of video. need to know more about crossover gait? click here). We noted she was crossing her arms over her body as well. We than had her run her hands and arms straight out. See the crossover disappear? Need to know more about arm swing? click here

We the had her do the same while walking. Easier to see, eh? That’s because it is often easier to “fudge” things when you are moving faster (ie: the basal ganglia of nervous system can interpolate where the body part is supposed to be, and because of momentum, there is less need for precision). When we do things slowly (like the 3 second Test), more precision is needed. Watch this short video clip a few more times.

The arms are essentially adducting when the arms cross over. The arms are reciprocally paired with the contralateral lower extremity. When you make a change in one, you often will make a change in the other.

Subtle. Yes. Easier to see when the task becomes more difficult. Yes. Pay attention, the answer is often right there if you look closely enough.

Providing the clues to help you be smarter, better, faster, stronger; we are The Gait Guys

special thanks to “Q” for allowing us to publish this video : )

How much does your Hallux Extend?

Last week, on Mondays post, we introduced potential areas for power leaks.

The common areas for leaks are:

  • great toe dorsiflexion
  • loss of ankle rocker
  • loss of knee flexion/extension
  • loss of hip extension
  • loss of balance/ proprioception


let’s take a look at a video of the 1st one:

Power leak 1: Great Toe Dorsiflexion

The big toe needs to extend AT LEAST 40 degrees and CLOSER TO 60 degrees for normal walking and running gait. If you do not have that available range of motion, then you will need to “borrow” it from somewhere else.

Common compensations include:

  • externally rotating the foot and coming off the inside of the great toe. this often causes a callus at the medial aspect of the toe. This places the foot in more pronation (plantar flexion, eversion and abduction) so it is a poorer lever.
  • internally rotating the foot and coming off the outside of the foot. This places the foot in more supination ( dorsiflexion, inversion and adduction) and it is therefore a more rigid lever. This often causes tripping or stumbling because of a lack of adequate dorsiflexion of the foot.
  • lifting the foot off the ground and avoiding toe off at terminal stance phase
  • abbreviating the step length to accommodate the amount of available great toe dorsiflexion.

Are YOU losing power? Tune in here for more tips on this series in the coming weeks!

The Gait Guys. Increasing your gait literacy with each and every post.

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Welcome to Rewind Friday, Folks. Today we review the importance of the great toe extensor. Enjoy!

Gait Topic: The Mighty EHB (The Short extensor of the big toe, do not dismiss it !)

Look at this beautiful muscle in a foot that has not yet been exposed to hard planar surfaces and shoes that limit or alter motion! (2 pics above, toggle back and forth)

The Extensor Hallicus Brevis, or EHB as we fondly call it (beautifully pictured above causing the  extension (dorsiflexion) of the child’s proximal big toe) is an important muscle for descending the distal aspect of the 1st ray complex (1st metatarsal and medial cunieform) as well as extending the 1st metatarsophalangeal joint. It is in part responsible for affixing the medial tripod of the foot to the ground.  Its motion is generally triplanar, with the position being 45 degrees from the saggital (midline) plane and 45 degrees from the frontal (coronal) plane, angled medially, which places it almost parallel with the transverse plane. With pronation, it is believed to favor adduction (reference). Did you ever watch our video from 2 years ago ? If not, here it is, you will see good EHB demo and function in this video. click here

It arises from the anterior calcaneus and inserts on the dorsal aspect of the proximal phalynx. It is that quarter dollar sized fleshy protruding, mass on the lateral aspect of the dorsal foot.  The EHB is the upper part of that mass. It is innervated by the lateral portion of one of the terminal branches of the deep peronel nerve (S1, S2), which happens to be the same as the extensor digitorum brevis (EDB), which is why some sources believe it is actually the medial part of that muscle. It appears to fire from loading response to nearly toe off, just like the EDB; another reason it may phylogenetically represent an extension of the same muscle.

*The EDB and EHB are quite frequently damaged during inversion sprains but few seem to ever look to assess it, largely out of ignorance. We had a young runner this past year who had clearly torn just the EHB and could not engage it at all. He was being treated for lateral ankle ligament injury when clearly the problem was the EHB, the lateral ligamentous system had healed fine and this residual was his chief problem.  Thankfully we got the case on film so we will present this one soon for you !  In chronic cases we have been known to take xrays on a non-standard tangential view (local radiographic clinics hate us, but learn alot from our creativity) to demonstrate small bony avulsion fragments proving its damage in unresolving chronic ankle sprains not to mention small myositis ossificans deposits within the muscle mass proper.

Because the tendon travels behind the axis of rotation of the 1st metatarsal phalangeal joint, in addition to providing extension of the proximal phalynx of the hallux (as seen in the child above), it can also provide a downward moment on the distal 1st metatarsal (when properly coupled to and temporally sequenced with the flexor hallicus brevis and longus), assisting in formation of the foot tripod we have all come to love (the head of the 1st met, the head of the 5th met and the calcaneus).

Wow, all that from a little muscle on the dorsum of the foot.

The Gait Guys. Definitive Foot Geeks. We are the kind of people your podiatrist warned you about…

Well, how convenient.  A fantastic picture for teaching from the cover of one of our favorite magazines. 
 For this post, lets start with the gal on the left in the pink shirt. 1st of all, she is running in flip flops. Since these require so much long flexor activity to keep them on, not the best footwear choice, in our opinion. Check out that exaggerated left sided arm swing. This goes to propel herself forward. Why the extra effort? Check out her right (stance phase leg). What do you see? The knee points outward while the foot is planted. We are looking at either external tibial torsion or a femoral retrotorsion. Did you pick up the compensatory head tilt to the left? The vestibular system has become involved, and the trapezius and levator scapula seem to be it’s target (thus the shoulder hike and ipsilateral rotation), as well as the ipsilateral lateral benders and rotators of the cervical spine, namely the splenius cervicis and capitis (the multifidus/rotatores are contralateral rotators). 
 How about the subtle pelvic shift to the right? and the mild crossover gait (note the adduction of the left knee across midline). 
 It would be great to see a shot of her barefoot to see what changes, as increased long flexor activity has both local (impaired ankle rocker, excessive forefoot inversion, reciprocal inhibition of the anterior compartment muscles of the lower leg) as well as long distance (namely increased flexor drive to the brainstem and cerebellum) implications. We would want to see this (as well as examine her) before making any recommendations other than LOSE THE FLIP FLOPS GIRLFRIEND. 
 Wow, all that and we have only scratched the surface. 

   We remain the geeks of gait: Ivo and Shawn

Well, how convenient. A fantastic picture for teaching from the cover of one of our favorite magazines.

For this post, lets start with the gal on the left in the pink shirt. 1st of all, she is running in flip flops. Since these require so much long flexor activity to keep them on, not the best footwear choice, in our opinion. Check out that exaggerated left sided arm swing. This goes to propel herself forward. Why the extra effort? Check out her right (stance phase leg). What do you see? The knee points outward while the foot is planted. We are looking at either external tibial torsion or a femoral retrotorsion. Did you pick up the compensatory head tilt to the left? The vestibular system has become involved, and the trapezius and levator scapula seem to be it’s target (thus the shoulder hike and ipsilateral rotation), as well as the ipsilateral lateral benders and rotators of the cervical spine, namely the splenius cervicis and capitis (the multifidus/rotatores are contralateral rotators).

How about the subtle pelvic shift to the right? and the mild crossover gait (note the adduction of the left knee across midline).

It would be great to see a shot of her barefoot to see what changes, as increased long flexor activity has both local (impaired ankle rocker, excessive forefoot inversion, reciprocal inhibition of the anterior compartment muscles of the lower leg) as well as long distance (namely increased flexor drive to the brainstem and cerebellum) implications. We would want to see this (as well as examine her) before making any recommendations other than LOSE THE FLIP FLOPS GIRLFRIEND.

Wow, all that and we have only scratched the surface.

We remain the geeks of gait: Ivo and Shawn

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Remember this kiddo?

We have been following the natural development of this little guy for some time now. For a review, please see here (1 year ago) and here (2 years ago) for our previous posts on him.

In the top 2 shots, the legs are neutral. The 3rd and 4th shots are full internal rotation of the left and right hips respectively. The last 2 shots are full external rotation of the hips.

Well, what do you think now?

We remember that this child has external tibial torsion and pes planus. As seen in the supine photo, when the knees face forward, the feet have an increased progression angle (they turn out). We are born with some degree / or little to none, tibial torsion and the in-toeing of infants is due to the angle of the talar neck (30 degrees) and femoral anteversion (the angle of the neck of the femur and the distal end is 35 degrees).  The lower limbs rotate outward at a rate of approximately 1.5 degrees per year to reach a final angle of 22 degrees….. that is of course if the normal de rotation that a child’s lower limbs go through occurs timely and completely.

He still has a pronounced valgus angle at the the knees (need a review on Q angles? click here). We remember that the Q angle is negative at birth (ie genu varum) progresses to a maximal angulation of 10-15 degrees at about 3.5 years, then settles down to 5-7 degrees by the time they have stopped growing. He is almost 4 and it ihas lessend since the last check to 15 degrees.

His internal rotation of the hips should be about 40 degrees, which it appears to be. External rotation should match; his is a little more limited than internal rotation, L > R. Remember that the femoral neck angle will be reducing at the rate of about 1.5 degrees per year from 35 degrees to about 12 in the adult (ie, they are becoming less anteverted).

At the same time, the tibia is externally rotating (normal tibial version) from 0 to about 22 degrees. He has fairly normal external tibial version on the right and still has some persistent internal tibial version on the left. Picture the hips rotating in and the lower leg rotating out. In this little fellow, his tibia is outpacing the hips. Nothing to worry about, but we do need to keep and eye on it.

What do we tell his folks?

  • He is developing normally and has improved significantly since his original presentation to the office
  • Having the child walk barefoot has been a good thing and has provided some intrinsic strength to the feet
  • He needs to continue to walk barefoot and when not, wear shoes with little torsional rigidity, to encourage additional intrinsic strength to the feet
  • He should limit “W” sitting, as this will tend to increase the genu valgus present
  • We gave him 1 leg balancing “games” and encouraged agility activities, like balance beam, hopping, skipping and jumping on each leg individually

We are the Gait Guys, promoting gait and foot literacy, each and every post.

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Holy Hand Grenades! What kind of shoe do I put these feet in?

Take a look at these feet. (* click on each of the photos to see the full photo, they get cropped in the viewer) Pretty bad, eh? How about a motion control shoe to help things along? NOT! OK. but WHY NOT? Let’s take a look and talk about it.

To orient you:

  • top photo: full internal rotation of the Left leg
  • 2nd photo: full internal rotation of the Right leg
  • 3rd photo: full external rotation of the Left leg
  • last photo: full external rotation of the Right leg

Yes, this gal has internal tibial torsion (yikes! what’s that? click here for a review).

Yes, it is worse on the Left side

Yes, she has a moderate genu valgus, bilaterally.

If someone has internal tibial torsion, the foot points inward when the knee is in the saggital plane (it is like a hinge). The brain will not allow us to walk this way, as we would trip, so we rotate the feet out. This moves the knee out of the saggital plane (ie. now it points outward).

What happens when we place a motion control shoe (with a generous arch and midfoot and rearfoot control) under the foot? It lifts the arch (ie it creates supination and it PREVENTS pronation). This creates EXTERNAL rotation of the leg and thigh, moving the knee EVEN FURTHER outside the saggital plane. No bueno for walking forward and bad news for the menisci.

Another point worth mentioning is the genu valgus. What happens when you pick up the arch? It forces the knee laterally, correct? It does this by externally rotating the leg. This places more pressure/compression on the medial aspect of the knee joint (particularly the medial condyle of the femur). Not a good idea if there is any degeneration present, as it will increase pain. And this is no way to let younger clients start out their life either.

So, what type of shoe would be best?

  • a shoe with little to no torsional rigidity (the shoe needs to have some “give”)
  • a shoe with no motion control features
  • a shoe with less of a ramp delta (ie; less drop, because more drop = more supination of the foot (supination is plantarflexion, inversion and adduction)
  • a shoe that matches her sox, so as not to interfere with the harmonic radiation of the colors (OK, maybe not so much…)

Sometimes giving the foot what it appears to need can wreak  havoc elsewhere. One needs to understand the whole system and understand what interventions will do to each part. Sometimes one has to compromise to a partial remedy in one area so as not to create a problem elsewhere. (Kind of like your eye-glass doctor. Rarely do they give you the full prescription you need, because the full prescription might be too much for the brain all at once.  Better to see decent and not fall over, than to see perfectly while face down in the dirt.) 

Want to know more? Consider taking the National Shoe Fit Certification Program. Email us for details: thegaitguys@gmail.com.

We are the Gait Guys, and yes, we like her sox : )

Welcome to rewind Friday, Folks. This week we have hammered on arm  swing. This one is from a year ago and seemed germane to this weeks posts.

Arm swing in gait and running. Why it is crucial, and why it must be symmetrical.

It becomes clear that once you get the amazing feats seen in this video out of your head, and begin to watch just the variable use of the arms that you will begin to appreciate the amazing need for arm swing and function in movement.

We have written many articles on arm swing and its vital importance in gait and running. Have you missed all these articles ?  If so, go to our blog main page, type in “arm swing” in the search box and you will have a solid morning of readings at your fingertips.  We are still not done writing about this most commonly forgotten and overlooked aspect of gait and running analysis, and we probably never will be done.  Why is no one else focusing on it ?  We think it is because they do not see or understand its critical importance.

Without the presence and use of the arms in motion things like acceleration, deceleration, directional change, balance and many other critical components of body motion are not possible.

What is perhaps equally important for you to realize, as put forth in:

Huang et al in the Eur Spine Journal, 2011 Mar 20(3) “Gait Adaptations in low back pain patients with lumbar disc herniation: trunk coordination and arm swing.”

is that as spine pain presents, the shoulder and pelvic girdle anti-phase begins to move into a more in-phase favor.  Meaning that the differential between the upper torso twist and pelvic twist is reduced. As spine pain presents, the free flowing pendulum motions of the upper and lower limbs becomes reduced to dampen the torsional “wringing” on the spine. When this anti-phase is reduced then arm swing should be reduced. The central neural processing mechanisms do this to reduce spinal twisting, because with reduced twist means reduced spinal motor unit compression and thus hopefully less pain. (Yes, for you uber biomechanics geeks out there, reduced spine compression means increased shear forces which are favorite topics of many of our prior University instructors, like Dr. Stuart McGill). The consequence to this reduced spinal rotation is reduced limb swing.  And according to

Collins et al Proc Biol Sci, 2009, Oct 22 “Dynamic arm swinging in human walking.”

“normal arm swinging requires minimal shoulder torque, while volitionally holding the arms still requires 12 % more metabolic energy.  Among measures of gait mechanics, vertical ground reactive moments are most affected by arm swinging and increased by 63% without arm swing.”

So, it is all about efficiency and protection. Efficiency comes with fluid unrestricted movements and energy conservation but protection has the cost of wasting energy and reduced mobility through a limb(s) and spine.

In past articles we have carried these thoughts into historical functional needs of man such as carrying spears and of modern day man in carrying briefcases.   Today we show a great high functioning video of another parkour practitioner.  Parkour is a physical discipline and non-competitive sport which focuses on efficient movement around obstacles.  Watch closely the use of the arms. The need for arm use in jumping, in balance, in acceleration etc. It becomes clear that once you get the amazing feats seen in this video out of your head, and begin to watch just the use of the arms that you will begin to appreciate the amazing need for arm swing and function in movement.

There is a reason that in our practices we treat contralateral upper and lower limbs so much.  Because if you are paying attention, these in combination with the unilateral loss of spinal rotation are the things that need attention. 

Yup, we are The Gait Guys….. we have been paying attention to this stuff long before the functional movement assessment programs became popular.  If you just know gait, one of the single most primitive patterns other than crawling and breathing and the like, you will understand why you see altered squats, hip hinges, shoulder ROM screens etc.  You have to have a deep rooted fundamental knowledge of the gait central processing and gait parameters. If you do not, every other screen that you put your athlete or patient through might have limited or false leading meaning. 

Shawn and Ivo …  combining 40 years of orthopedics, neurology, biomechanics and gait studies to get to the bottom of things.

Faulty Arm Swing provides clues to gait pathology. 

 Don’t think that just because you see aberrant arm swing that you should “coach” it out of someone.  It is very likely there for a reason. We discuss tonight how the leg swing is more deeply neurologically embedded, more so than arm swing.  So, fixing something you do not like in their arm swing is very possibly the wrong solution and by doing just that you are forcing your client into a new compensatory CPG (central pattern generator) which is essentially a compensation to their compensation.   Fix the problem, go for its roots ! 
 This is one of our slides for tonights lecture.  This is from the European Spine Journal 2011.  More posterior arm swing can help improve impaired hip extension and gluteal function. A nice compensatory fix to reduce spine rotation in a spinal pain patient, more hip extension means that less pelvic obliquity needs to be acquired (less obliquity in the pelvic girdle means less spine rotation and thus less spine compression. This is a brain based phenomenon, the brain is engaging a pain avoidance CPG.  
 You gotta know your biomechanics, you gotta know your neurology and you MUST understand and recognize normal and abnormal gait patterns if you choose to work with humans ! 
 Join us tonight on  www.onlinece.com  for an in-depth hour talking about the biomechanics and neurobiology behind normal and abnormal arm swing.  7pm central Wednesday  19th.  
  Shawn and Ivo, the gait guys

Faulty Arm Swing provides clues to gait pathology.

Don’t think that just because you see aberrant arm swing that you should “coach” it out of someone.  It is very likely there for a reason. We discuss tonight how the leg swing is more deeply neurologically embedded, more so than arm swing.  So, fixing something you do not like in their arm swing is very possibly the wrong solution and by doing just that you are forcing your client into a new compensatory CPG (central pattern generator) which is essentially a compensation to their compensation.   Fix the problem, go for its roots !

This is one of our slides for tonights lecture.  This is from the European Spine Journal 2011.  More posterior arm swing can help improve impaired hip extension and gluteal function. A nice compensatory fix to reduce spine rotation in a spinal pain patient, more hip extension means that less pelvic obliquity needs to be acquired (less obliquity in the pelvic girdle means less spine rotation and thus less spine compression. This is a brain based phenomenon, the brain is engaging a pain avoidance CPG. 

You gotta know your biomechanics, you gotta know your neurology and you MUST understand and recognize normal and abnormal gait patterns if you choose to work with humans !

Join us tonight on www.onlinece.com for an in-depth hour talking about the biomechanics and neurobiology behind normal and abnormal arm swing.  7pm central Wednesday 19th.

Shawn and Ivo, the gait guys