Podcast 106: Understanding Tendonopathies & Asymmetrical Bone density in athletes.

* Plus the global effects of Hallux Limitus, & Chronic exposure to routine high-impact, gravitational loads afforded to the support limb preferentially improved bone mass and structure

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Other Gait Guys stuff

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Monthly lectures at : www.onlinece.com type in Dr. Waerlop or Dr. Allen, ”Biomechanics”

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Show Notes:

New device to get people with paralysis back on their feet
Scientists have tested the world’s first minimally-invasive brain-machine interface, designed to control an exoskeleton with the power of thought

Splicing out torsions, and aberrant foo types ? Club foot ? etc

Scientists Capture Crispr’s Gene-Cutting in Action

The UK Just Green-Lit Crispr Gene Editing in Human Embryos

Asymmetries in limbs

Tension or compression ?
link to full text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3676165/

Concept: the forces have to go somewhere, it is a “passing the buck” system.  
We did this blog post here to explain:

The new muscle discovery !

tendinopathy vasculature: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4650849/

tendinopathy treatment paper: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2505250/

Dragging your tongue ? When the tongue of your shoe keeps getting pulled to the side. Do you know what it means ? It means plenty, if you are sharp.

By: Dr. Shawn Allen

This one pisses off most people it happens to. Why does it typically happen only on one side, on one shoe ? Look at the photo case above. Look closely to the left foot, the tongue of the shoe is pulled laterally compared to the right, or shall I say, dragged.

This is a fairly common phenomenon, and there is a reason for it, several actually. So, no, you do not need to staple the tongue to the shoe upper, or tighten your shoe laces, or stitch the tongue to the medial shoe upper. You need to stop externally spinning your foot in your darn shoe.  What ?!

Yes, you very well may be avoiding normal internal rotation progression of the pelvis over the fixated limb. Loss of internal hip rotation is often a common finding clinically. As one passes the swing leg forward, the forward progressing pelvis eventually meets this loss of internal rotation over the fixated leg and femoral head. The swing leg none the less progresses further forward to get to its’ heel strike and the stance phase leg has to externally spin over the ground (I like to give the analogy of putting out a cigarette butt on the ground or squishing a bug (PETA don’t come after me)). This is called an Abductory or Adductory twist (good video demo here) depending on whether your reference point is the forefoot or rear foot. Regardless, the heel is spinning inward, the forefoot is relatively spinning outward. This spin of the foot inside the shoe (this happens minutely just before the shoe spins on the ground) and pulls the tongue laterally with it.  

This problem can also come from, and often does, a premature heel rise from things like a:

  •  loss of ankle rocker
  • short calf
  • lack of hip extension
  • hallux rigidus / limitus or even a painful big toe
  • etc

There are even several other causes I will not list here today, I could have you waste your whole day on the list and the mental gymnastics of things to consider. Basically, anything that impairs the stance phase mechanics creating a premature heel rise or failure of completing internal hip rotation can cause an Abd/Adductor twist of the foot/heel and drag the tongue laterally. Sure, there are others, but the purpose of my blog post here today was to explain a neat little biomechanical phenomenon that  has huge clinical insight if you know what it means.  You cannot fix this problem if you do not do a physical exam, understand clean and faulty gait biomechanics, and maybe can even find small objects in a dark room.  What I mean is it takes some educated exploration and a curiosity to want to fix things.  

There are clues often right in front of you, all you have to do is pay attention and sometimes ask a simple question. 

“Mr. Jones, when you stick out your tongue, does it drag laterally ?”  

Ok, maybe not that exact question. But, when I see a loss of internal rotation or terminal hip extension in a runner, and when I have time to explain things deeply with a openly receiving client, I might start the conversation with that fun question and then explain what I really meant was the tongue of the shoe on that affected side. 

You can’t swallow bandaids to fix things, as much as you wish it was that easy. Sure, you can avoid all of this fun by buying a shoe that has the tongue of the shoe sewn to the medial upper of the shoe, but then you wouldn’t have to fix anything.  Where would you “get your fun on” then ?  Be brave, go all in, fix the problem dammit.  

These are the things that keep me up at night. Welcome to my nightmares.

Dr. Shawn Allen, one of the gait guys

Photo courtesy of this weartested.org link: http://weartested.org/wp-content/uploads/2015/03/altra-superior-2-top-socks.jpg

Got big toe pain? Think it’s gout? Think again!   Things are not always what they appear to be. 

This gent came in with first metatarsophalangeal pain which had begun a few months previous. His uric acid levels were borderline high (6) so he was diagnosed with gout.  It should be noted his other inflammatory markers (SED rate and CRP) were low. Medication did not make the symptoms better, rest was the only thing that helped. 

The backstory is a few months ago he was running in the snow and “punched through"the snow, hitting the bottom of his foot on the ground. Pain developed over the next few days and then subsided. The pain would come on whenever he try to run or walk along distances and he noticed a difficult time extending his big toe.

 Examination revealed some redness mild swelling over the 1st metatarsophalangeal joint (see pictures above) and hallux dorsiflexion of 10°.   If we raised the base of the first metatarsal and pushed down on the head of the 1st, he was able to dorsiflex the 1st MTP approximately 50°. He had point tenderness over the medial sesamoid. We shot the x-rays you see above. The films revealed a fracture of the medial sesamoid with some resorption of the bone.

The  sesamoid fracture caused the head of the 1st metatarsal to descend on one side, and remain higher on the other, altering the axis of rotation of the joint and restricting extension. We have talked about the importance of the axis of this joint in may other posts (see here and here).

 He was given exercises to assist in descending the first ray (EHB, toe waving, tripod standing).  He will be reevaluated in a week and if not significantly improved we will consider a wedge under the medial sesamoid. 

A pretty straight forward case of “you need to be looking in the right place to make the diagnosis”. Take the time to examine folks and get a good history.

The Banana Toe: The Force has to go somewhere. It’s a Jedi Gait Rule.

* note: there are 4 photos to today’s blog post. Be sure you click through all 4.

When you toe off, you have to toe off from somewhere in the foot unless you like an apropulsive hip flexion gait, where  you just lift you foot off the ground from foot flat, kind of like a true neurologic “foot drop” gait client would.  But, if you are lucky enough not to have a true foot drop, you are going to push off somewhere in the foot.  You can do it off the lateral foot (low gear toe off) and lesser toes, or you can do it off the big toe (high gear) the way we were built to do it. 

The above pictures show a nasty dorsal crown of osteophytes that is limiting hallux (big toe) extension/dorsiflexion. This is true hallus rigidus and hallux limitus. When this client attempts to toe off, the joint cannot normally partake in the activity, there is no Windlass effect, no posturing up over the sesamoids for mechanical advantage etc.   

In this scenario, there are two places you can put it, up into the next proximal joint(s) meaning the met-cuneiform joint or further down into the interphalangeal joint. In other words. the loads go proximal or distal to the limited joint, and they eventually play out there, over and over and over gain. The former option would basically mean you are pronating/dorsiflexing through the midfoot which is never good (can you say Saddle exostosis ! ouch !) or the latter option is to dorsiflex through the interphalangeal joint  and over time that toe begins to attenuate plantar ligamentous structures and extend beyond its normal limits resulting in the “Chiquita” toe (a upward bent toe resembling a banana shape). This will disable the long flexor of the great toe (FHL: flexor hallucis longus).and inhibit mechanical advantage of the extensor digitorum brevis.  If you struggle with the “how and why” behind this sentence in terms of restoration attempts, you need to watch my video here. It will offer you deeper insights.

Will this toe become painful ? yes, in time it is quite possible.  Is there much you can do? Sure, a rocker bottomed shoe will help take the load at toe off instead of forcing it into this toe or the midfoot.  Will an orthotic  help ? Well, this is a loaded question. If you are putting the forces into the midfoot choice as described above, the orthotic will block that motion and you will likely default option into the toe presentation above. So you are merely just moving loading forces around. It can be helpful, but you are quite possibly “robbing Peter to pay Paul” as they say.  The video I asked you to watch can be helpful but it will force that metatarsophalangeal joint into extension, a range it does not have, so it is not a remedy and not recommended.  Perhaps some awareness and slight increase in FHL(long toe flexor) use can be attained however.  These are tricky cases, simple in theory, but execution can be fussy and requires patient awareness and education. We like the rocker bottomed shoe as a nice easy solution and some increased FHL use awareness.  Help them find a little more FHL use by putting a pencil under the crease of the toe and help them to drive the tip of the toe down just a little out of that banana extension posture. It can help them control the overloading of the dorsal aspect of the interphalangeal joint.

As always, lets carry this forward into gait thoughts.  How is  hip extension going to be in this client ? How is glute strength ? Hip joint range ? Hip extension motor patterning ? Will the client go into anterior pelvic tilt to borrow the last range of hip extension ? Will the hamstrings have to accommodate ? Lots of yummy biomechanical and neurological mental gymnastics here. Bottom line answer to all the above ?  “ it depends, they will have to accommodate and compensate”.  And as the Jedi Gait Rule goes, “the Force as to go somewhere”.

Shawn Allen, one of the gait guys

Yes, you are looking INSIDE this toe. That IS a screw and metal plate in that toe. 

What kind of stuff finds its way into your office ? I get all kinds of things it seems, at least once a day something comes in that makes me scratch my head. 

This client just wanted my opinion and thoughts on their toe and their gait once they are ambulating again. They have had multiple surgeries to this poor foot. You can see multiple scars over multiple digits and metatarsals.  This is the 3rd surgery to the big toe, the last 2 have been attempts at correcting failed prior surgeries. This is obviously the last straw surgery, total fusion of the metatarsophalangeal joint.  What is interesting in this case is that this plate was taken out about 4 weeks ago, and the skin was stretched back over and the wound closed up (forgot to take update photo for you). I saw it yesterday, and I was amazed at how healed up the area was. They are months post op now, and they can load the toe heavily now, that is always amazing to me. The body’s healing ability is a miracle. Of course, if you have been with us here long enough you will know that my “concern button” immediately got pushed but the client was proactive and asked the question before my oral diarrhea of concerns started.

So, they wanted to know about their gait and what to watch out for.  Off the top of your head, without thinking, you should be able to rattle off the following:

  • impaired toe off
  • premature heel rise
  • watchful eye on achilles issues
  • impaired hip extension and gluteal function
  • impaired terminal ankle plantar flexion (because they cannot access the synergists FHL and FHB)
  • impaired terminal ankle dorsi flexion (because they cannot access the synergists EHL and EHB)
  • lateral toe off which will promote ankle and foot inversion, which will challenge the peronei
  • frontal plane hip-pelvis drift because of the lateral toe off and lack of glute function
  • possible low back pain/tightness because of the  frontal plane pelvis drift and from altered hip extension motor patterning (and glute impairment)
  • possible knee pain from tracking challenges because they cannot complete medial tripod loading and thus sufficient pronation to internally spin the limb to get the knee to sagittal loading
  • impaired arm swing, more notable contralaterally

There is more, but that is enough for now. You need to know total body mechanics, movement patterns, normal gait cycle events (you have to know normal to know abnormal) and more. You have to know what normal is to understand when you are looking at abnormal.

* So, dial this back to something more simple, a “stubbed toe”, a painful sesamoid, painful pronation or a turf toe or hallux limitus.  They will all have the same list of complications that need to be evaluated, considered and addressed. This list should convey the importance that if your client has low back pain, examining the big toe motion is critical. Also, if you are just looking at the foot and toe in these cases, pack your bags … .  you don’t belong here. If you are just adjusting feet and toes and playing with orthotics while the list above does not constantly file back and forth through your brain, again, pack all your bags, grab your cat and leave town (just kidding, try reading more and get to some seminars).

If you know the complicated things, then the simple things become … … . . simple.

Your local treadmill gait analysis guru should know all of this if they are going to recommend shoes and exercises. Shame on them if there is no physical exam however. The data roadmap from the gait analysis software print out is not going to get you even out of the driveway let alone down the street. The data is going to tell you what you are doing to compensate, not tell you what is wrong. You must know anatomy, biomechanics, neurology, orthopedics and how to apply them to get the recipe right, not just which shoe in a store will unload the medial tripod of the foot or which exercise will lengthen your stride on the left. 

… .  sorry for the rant, too much coffee this morning, obviously.

Shawn Allen, one of the gait guys

The Great toe’s effect on external hip rotation.

We have a simple video for you today. 

When we assess our clients for gait and locomotion we do a quick screen of all the big player joints, from the toes at least up into the thoracic spine to start. Loss of mobility/range of motion means probable functional impairment. 

In this video we display the effects of the Windlass Mechanism of the great toe. A windlass mechanism according to Wikipedia is:

a type of winch used especially on ships to hoist anchors and haul on mooring lines and, especially formerly, to lower buckets into and hoist them up from wells.

In this case, dorsiflexing the big toe spools the plantarfascia and flexor hallucis longus and brevis around the metatarsophalangeal joint (1st. MTPJ), thus pulling the heel towards the forefoot thus raising the arch. When the arch raises, the talus moves cephalad (upwards) and because of the supinatory movement orientation, it spins the tibial externally which in turn spins the femur externally. This is what you see in this video, note the blue dots being carried laterally with the limb external rotation.

The point here today, if you have loss of external hip rotation, it could be crying for you to evaluate the range of motion of the 1st MTP joint , it could be crying for you to evaluate the skill of toe extension, strength or endurance or all of the above. Impairment of the 1st MTP has great inroads into ineffective locomotion. You must have decent range of motion to effectively supinate, to effectively toe off, to externally rotate the limb, to effectively acquire hip extension to maximize gluteal use.  Thus, one could easily say that impaired hallux/great toe extension (skill, ability, endurance, strength) can impair hip extension (and clean hip extension patterning) and result in possible terminal propulsive gait extension occurring through the lumbar spine instead of through the hip joint proper.

Think of the effects of two asymmetrical great toe extensions, comparing the great toe left to right. Asymmetry in the limbs, pelvis, hip extension and perhaps worse, the lumbar spine, is a virtual guarantee.  Compare hallux extension side to side, if you can achieve symmetry through skill, endurance and strength retraining, you must do it. If you have a hallux limitus, a bunion or anything that impairs the symmetry of great toe extension side to side, you have some interesting work to do. 

You have to know what you have in your client, and know what it means to their locomotion.  Seeing or recognizing what you have must translate into understanding and action. 

Play mental games with clinical entities.  In this case, if at terminal toe off you did not have full hallux extension like in this client, and thus you did not get that last little final external rotation spin in the limb at the hip … . . what could that do to your gait ? Go tape your toe and limit terminal extension (terminal dorsiflexion) and walk around, to feel it in yourself is to get first hand experience. 

Shawn Allen, one of the gait guys