Yep, these shoes stink for this gal...

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Look at the left shoe and compare it to the right. See how the upper is canted on the outsole? This “varus cant” can create lots of problems or could actually be beneficial, believe it or not, depending upon the pathology.

In this particular persons story, it was NOT a good thing. They have an anatomical short leg on the left-hand side. If you remember from following us here in the past, generally speaking, the shorter leg tide tends to be more supinated and the forefoot tends to be in more varus. This means more of a “reach” with that foot during the contact phase of gait, Whether that’s running or walking. This generally means that the forefoot will pronate more on the long leg side.

This shoe “defect“ may actually be benefit for someone who has too much rear or mid foot pronation as it would “delay” pronation by starting to rearfoot in an inverted position at heel strike.

The Fix?

You could grind the sole into varus an equal amount to equal the varus cant. In our opinion, not a good idea.

You could return the shoe (that’s what this person is doing) and get another one

In addition, you could…

Give the person a 3 mm sole lift to correct for the leg length discrepancy

Make sure they have adequate range of motion in the first ray on the short leg side to be be able to plantar flex the 1st ray and reach the ground

Make sure they have adequate control of the core musculature as well as foot intrinsic musculature during stance phase.

Dr Ivo Waerlop, one of The Gait Guys

#badshoes #theshoeistheproblem #forefootvarus #leglengthdifference
#gaitproblem

Plantar Plate Gait

This girl has a (healing) plantar plate lesion on the left hand side at the head of the second met. She also has an anatomical short leg on the same side. Her second metatarsal of both feet or longer than the first

A few things I hope you notice about the video:

  • Can you see how she “reaches“ to get to the ground with her left foot?

  • Can you see how her left foot is more inverted that strikes in the right, creating a greater amount of forefoot pronation that needs to be controlled?

  • Can you see how poor her motion control is of her pronation on the left foot with the sudden “crash” at impact?

  • Have you noticed her “crossover“ gait?


Does it make sense that because of her anatomy and running style, that the constant reach, increased forefoot inversion and lack of pronation control (which causes more abduction of the forefoot at toe off); this drives the force to the second metatarsal head which is longer and more prominent and is more than likely what led to her plantar plate lesion in the first place?


Remediation?

  • A 3 mm full length sole lift for the left foot

  • Foot intrinsic strengthening exercises

  • Hip abduction strengthening exercises/drills

  • Moving her more to a “midfoot strike” running gait with toes extended to engage the windlass


Dr Ivo Waerlop, one of The Gait Guys


#plantarplate #gaitanalysis #crossovergait #leglengthdifference #thegaitguys


When you see this, you should be thinking one of 3 possible etiologies...

Cardinal sign of either a forefoot supinatus/forefoot varus or collapsing midfoot

I was hiking behind this young chap over the weekend along with my son and friends. Note the amount of calcaneal eversion present on the right side that is not present on the left. Also note the increased progression angle of the right foot and subtle circumduction of the extremity.

In my experience, you would generally see this much calcaneal diversion and one of three scenarios:

1. Moderate leg length discrepancy with the increased calcaneovalgus occurring on the longer leg side. This would support the amount of circumduction were seeing on the right side.

2. When there is a forefoot supinatus present and and inadequate range of motion available in the midfoot and/or forefoot. This is most likely the case here.

3. In moderate To severe midfoot collapse. This is clearly not the case as the medial aspect of the shoe is usually “blown out”.

Next time you see an everting rearfoot, think about these three possible etiologies.

Dr Ivo Waerlop, on of The Gait Guys

#evertedrrarfoot #calcanealvalgus #shortleg #forefootsupinatus #forefootvarus #gaitanalysis #thegaitguys

The amazing power of compensation. Coming to a patient in your office… Maybe today

This gal has had a right sided knee replacement. She has an anatomical right short leg, a forefoot supinatus, an increased Q angle and a forefoot adductus. So, what’s the backstory?

When we have an anatomical short leg, we will often have a tendency to try to “lengthen“ that extremity and “shorten” the longer extremity. This is often accomplished through pelvic rotation although sometimes can be with knee flexion/extension or change in the Q angle. When the condition is long-standing, the body will often compensate in other ways, such as what we are seeing here.

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The fore foot can supinate in an attempt to lenthen the extremity. Note how the right extremity forefoot is in varus with respect to the rearfoot, effectively lengthening the extremity. As you can see from the picture, this is becoming a “hard“ deformity resulting in a forefoot varus.

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Over time, the forefoot has actually “adducted “ as you can see, again in an attempt to lengthen the extremity. Remember that supination is plantar flexion, abduction and inversion, all three which are visible here.


You will also see that the Q angle is less on the right side (se above), effectively lengthening that extremity, but not quite enough as we can see from the picture :-)



Dr Ivo Waerlop, one of The Gait Guys

#forefootadductus #shortleg #kneereplacement #tkr #forefootvarus #gait #thegaitguys

Sixth toe disease...That growth on the outside of your foot… Or on somebody’s foot is coming to see you…

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You know what we’re talking about. That extra growth on the lateral aspect of the foot that happens way too often and many of your clients. A Taylor’s bunion or sometimes referred to as a “bunionette”. 

What is the usual fix?

Usually in a ski boot or hiking boot, they blow out the lateral side of the shoe. This is usually not a good fix because most of these folks have internal tibial torsion and somewhat of a forefoot supinatus/varus.

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The internal tibial torsion places the knee outside the saggital plane and an arch support without a forefoot valgus post will just push it further out, creating a conflict at the knee. The forefoot supinatus and/or varus places them on the outside of the foot as well. Remember, most of these folks are ALREADY on the outside of the foot and the foot wants to migrate laterally...so creating more space just means it migrates farther. Good thought, doesn’t work that way.

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So what did we do?

  • We created a valgus post for the forefoot (see picture above) tapering from lateral to medial and to help “push“ the distal aspect of the first ray down (because there was motion available that was not being used)

  • We gave him exercises to help descend the first ray like the extensor hallucis brevis exercise, toe waving as well as peroneus longus exercises

  • We gave him plenty of balance and coordination work

    Dr Ivo Waerlop, one of The Gait Guys




#6thtoe #internaltibialtorsion #forefootvarus # forefootsupinatus #gaitanalysis #thegaitguys







Holy Forefoot Flare, Batman!


Some sources say foot strike pattern does not matter. We disagree.

Look at this gal who midfoot/forefoot strikes. She also has a forefoot supinatus, a plastic condition where the forefoot is inverted with respect to the rearfoot. Take that combination and put it in a shoe with a forefoot flare and what do you get? Can you say AMPLIFICATION?

We’re not saying this is a bad shoe or even the wrong shoe. But, if she is going to run in this shoe, we will need to help her gain more ROM in her forefoot ( and some pelvic and hip stability) dodge doesn’t have to crash into eversion on each landing.

Help your patients with shoe selection. Something with less of a lateral flare in the forefoot would certainly make her life easier.

Need to know more? Consider taking our National Shoe Fit Program: link here:

Dr Ivo Waerlop, one of The Gait Guys

#badshoes #forefootflare #thegaitguys #forefootsupinatus #lateralflare #inversion

The muscle they named wrong?

Why would you name a muscle after its supposed function when its function is actually something totally different? Probably due to what made sense from how it looked, not by how it acted. Of course, we are talking about the abductor hallucis.

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Think about all the anatomy you have learned over the years. Think about all the taxonomy and how it was done: sometimes by thename of the discoverer and more often by its anatomical location. The abductor hallucis seems to be the latter. 

The abductor and adductor hallicus function from approximately midstance to pre swing (1-4) (toe off), applying equal and opposite rotational vectors of force (in an ideal world) of the proximal phalynx of the hallux. This should resolve into a purely compressive force (5). In a closed chain environment, the transverse head of the adductor hallicus should act to prevent “splay” of metatarsals, along with the lumbricals and interossei (6), providing stabilzation of the forefoot (7) and rearfoot (8) during preswing, while the oblique head serves to help maintain the medial longitudinal arch. 

The abductor hallicus is actually a misnomer, as it most cases it is not an abductor but rather a plantar flexor of the 1st ray, particularly the proximal hallux, (assisting the peroneus longus) and supinator about the oblique midtarsal joint axis (5).  In the majority of cases, there doesn’t appear to be a separate, distinct insertion of the adductor hallicus to the base of the proximal phalynx, but rather a conjoint insertion with the lateral head of the flexor hallicus bevis into the lateral sesamoid and base of the proximal phalynx (9-11), emphasizing more of its plantar flexion function and stabilizing actions, rather than abduction. 

In one EMG study of 20 people with valgus (12) they looked at activity of adductor and abductor hallucis, as well as flexor hallucis brevis and extensor hallucis longus. They found that the abductor hallucis had less activity than the adductor. No surprise here; think about reciprocal inhibition and increased activity of the adductor when the 1st ray cannot be anchoroed. They also found EMG amplitude greater in the abductor hallucis by nearly two fold in flexion. 

So, the abductor hallucis seems to be important in abduction but more important in flexion. Either way, it is a stance phase stabilizer that we are beginning to know a lot more about. As for the name? You decide...



Dr Ivo Waerlop, one of The Gait Guys



1. Basmajian JV, Deluca CJ . Muscle Alive. Their Functions Revealed by Electromyography Williams and Wilkins. Baltimore, MD 1985, 377

2. Root MC, Orien WP, Weed JH. Normal and Abnormal Function of the Foot. Clinical Biomechanics, Los Angeles, CA 1977

3. Mann RA. Biomechanics of Running. In Pack RP. d. Symposium on the foot and leg in running sports. Mosby. St Louis, MO 1982:26

4. Lyons K, Perry J, Gronley JK. Timing and relative intensity of the hip extensor and abductor muscle action during level and stair ambulation. Phys Ther 1983: 63: 1597-1605

5. Michaud T. Foot Orthoses and Other Forms of Conservative Foot Care. Newton MA 1993: 50-55

6. Fiolkowski P, Brunt D, Bishop et al. Intrinsic pedal musculature support of the medial longitudinal arch: an electromyography study. J Foot & Ankle Surg 42(6) 327-333, 2003

7. Travell JG, Simons DG. Myofascial Pain and Dysfunction: The Trigger Point Manual. Williams and Wilkins, Baltimore 1992; 529

8. Kalin PJ, Hirsch BE. The origin and function of the interosseous muscles of the foot. J Anat 152, 83-91; 1987

9. Owens S, Thordarson DB. The adductor hallucis revisited. Foot Ankle Int. 2001 Mar;22(3):186-91. Am J Phys Med Rehabil. 2003 May;82(5):345-9.

10. Brenner E.Insertion of the abductor hallucis muscle in feet with and without hallux valgus. Anat Rec. 1999 Mar;254(3):429-34.

11. Appel M, Gradinger R. [Morphology of the adductor hallux muscle and its significance for the surgical treatment of hallux valgus][Article in German] Orthop Ihre Grenzgeb. 1989 May-Jun;127(3):326-30.

12. Arinci I, Geng H, Erdem HR, Yorgancioglu ZR Muscle imbalance in hallux valgus: an electromyographic study. Am J Phys Med Rehabil. 2003 May;82(5):345-9.


#halluxvalgus #halluxabductovalgus #bunion #footmuscleactivity #gait #thegaitguys



The Short Foot Exercise

Here it is, in all its glory...Our version of the short foot exercise. Love it or hate it, say it “doesn’t translate”, we find it a useful training tool for both the patient/client as well as the clinician. It awakens and creates awareness of the sometimes dormant muscles in the user and offers a window to monitor progression for them, as well as the observer.

Remember that the foot intrinsics are supposed to be active from midstance through terminal stance/pre swing. Having the person “walk with their toes up” to avoid overusing the long flexors is a cue that works well for us. This can be a useful adjunct to your other exercises on the road to better foot intrinsic function.


Dr Ivo Waerlop, one of The Gait Guys

Sulowska I, Mika A, Oleksy Ł, Stolarczyk A. The Influence of Plantar Short Foot Muscle Exercises on the Lower Extremity Muscle Strength and Power in Proximal Segments of the Kinematic Chain in Long-Distance Runners Biomed Res Int. 2019 Jan 2;2019:6947273. doi: 10.1155/2019/6947273. eCollection 2019

Okamura K, Kanai S, Hasegawa M, Otsuka A, Oki S. Effect of electromyographic biofeedback on learning the short foot exercise. J Back Musculoskelet Rehabil. 2019 Jan 4. doi: 10.3233/BMR-181155. [Epub ahead of print]

McKeon PO, Hertel J, Bramble D, et al. the foot core system: a new paradigm for understanding intrinsic foot muscle function Br J Sports Med March 2014 doi:10.1136/bjsports-2013- 092690

Dugan S, Bhat K: Biomechanics and Analysis of Running Gait Phys Med Rehabil Clin N Am 16 (2005) 603–621

Bahram J: Evaluation and Retraining of the Intrinsic Foot Muscles for Pain Syndromes Related to Abnormal Control of Pronation http://www.aptei.ca/wp-content/uploads/Intrinsic-Muscles-of-the-Foot-Retraining-Jan-29-05.pdf


#shortfootexercise #footexercises #footrehab #thegaitguys #gaitanalysis #gaitrehab #toesupwalking



https://vimeo.com/342800960

Have you seen this?

Patterns. That’s what it’s about a lot of times. Dr Allen and I are always looking for patterns or combinations of muscles which work together and seem to cause what appear to be predictable patterns; like a weak anterior compartment and a weak gluteus maximus, or a weak gluteus medius and contralateral quadratus lumborum.

Here is an interesting story and a new combination that at least I have never seen before

I had a 11-year-old right footed soccer player from my son’s soccer team coming to see me with bilateral posterior knee pain which began during a soccer game while he was “playing up” on his older brothers team. He did need to do a lot of jumping as well as cutting. He is generally a midfielder/Forward. Well experienced player and “soccer is his life“.

My initial thoughts were something like a gastroc dysfunction or a Baker’s cyst. On examination, no masses or definitive swelling noted behind either knee. He did have tenderness to moderate degree over the right plantaris and tenderness as well as 4/5 weakness of the left popliteus. There was a loss of long axis extension of the talo crural articulations bilaterally with the loss of lateral bending to the right and left at L2-L3.

If you think about the mechanics of the right footed kicker (and try this while kicking a soccer ball yourself) it would be approximately as follows: left foot would be planted near the ball and the tibia/femur complex would be internally rotating well the foot is pronating and the popliteus would be eccentrically contracting to slow the rotation of the femur and the tibia. The right foot will be coming through and plantarflexion after a push off from the ball of the foot firing the triceps surae and plantaris complexes. He would be “launching“ off of the right foot and landing on his left just prior to the kick, causing a sudden demand on the plantar flexors; with the plantaris being the weak link. As the kicking leg follows through, the femur of the stance phase leg needs to externally rotate (along with the tibia) at a faster rate than the tibia (otherwise you could injure the meniscus) the popliteus would be contracting concentrically. A cleat, because it increases the coefficient of friction with the ground would keep the foot on the ground solidly planted and The burden of stress would go to the muscles which would be extremely routine leg and close chain which would include the semimembranosus/tendinosis  complex as well as the vastus medialis and possibly gracilis and short adductor, along with the popliteus.

I have to say and all of my years of practice I’ve never seen this combination type of injury before involving these two muscles specifically and am wondering if anyone else has seen this?

Dr Ivo Waerlop, one of The Gait Guys

#footproblem #gait #thegaitguys #soccerinjury #bilateralkneepain #popliteus #plantaris

image credit: https://commons.wikimedia.org/wiki/File:Slide2ACCA.JPG

image credit: https://commons.wikimedia.org/wiki/File:Slide2ACCA.JPG

The LAST word....on Lasts

The last (look inside the shoe on top of the shank) is the surface that the insole of the shoe lays on, where the sole and upper are attached).

Shoes are generally board lasted, slip lasted or combination lasted.

A board lasted shoe is very stiff and has a piece of cardboard or fiber overlying the shank and sole (sometimes the shank is incorporated into the midsole or last) . It can be effective for motion control (pronation) but can be uncomfortable for somebody who does not have this problem.

A slip lasted shoe is made like a slipper and is sewn up the middle. It allows great amounts of flexibility, which is better for people with more rigid feet.

A combination lasted shoe has a board lasted heel and slip lasted front portion, giving you the best of both worlds.

When evaluating a shoe, you want to look at the shape of the last (or sole). Bisecting the heel and drawing an imaginary line along the sole of the shoe determines the last shape. This line should pass between the second and third metatarsal. Drawing this imaginary line, you are looking for equal amounts of shoe to be on either side of this line.

Shoes have a straight, curved or semi curved last. The original idea of a curved last (banana shaped shoe) was to help with pronation. A curved last puts more motion into the foot and may force the foot through mechanics that is not accustomed to. Most people should have a straighter lasted shoe.

The shape of a last will effect the biomechanics of the foot. It should match why shape of the foot as closely as possible. Generally speaking, we recommend straighter lasts for folks that have a tendency to overpronate through the midfoot and curvier lasts for folks that have a more rigid foot.

Because the fore foot abducts during mid stance, if the last is curved, the lateral aspect of the foot can rub against the side of the shoe and create blistering of the little toe and if present long enough, a tailors bunion. A general rule of thumb is: "when in doubt, opt for a straighter one"

Dr Ivo Waerlop, one of The Gait Guys

#last #gait #foot #thegaitguys #lastshape #curvedlast #straightlast #gaitanalysis #pronation

Is your (or your athletes) cleat neutral or in varus?

Cleats are often the athletes primary interface with the ground and are responsible for transmitting the forces from the core and appendicular muscles down to the ground. The construction of the cleat as well as its characteristics (such as a forefoot varus cant in the forefoot, like this one here) can make all the difference in the world in athletic performance.

Dr Ivo Waerlop, one of The Gait Guys

#gait #thegaitguys #forefoot #varus #valgus #gaitanalysis #cleatproblems #cleatconstruction

The problems with some cleats....

Spring is here and Dr Ivo Waerlop of The Gait Guys talks about some common problems seen due to manufacturers defects in cleats and how they can affect athletes. From uppers put on the outsole incorrectly and contributing to and potentiating rearfoot varus and valgus to poor cleat placement affecting the 1st mtp mechanics; they all contribute to athlete performance.

Things seem to come in 3's...

Things tend to occur in threes. This includes congenital abnormalities. Take a look this gentleman who came in to see us with lower back pain.

Highlights with pictures below:

  • bilateral femoral retrotorsion

  • bilateral internal tibial torsion

  • forefoot (metatarsus) adductus

So why LBP? Our theory is the lack of internal rotation of the lower extremities forces that motion to occur somewhere; the next mobile area just north is the lumbar spine, where there is limited rotation available, usually about 5 degrees.

Dr Ivo Waerlop, one of The Gait Guys.

#tibialtorsion #femoraltorsion #femoralretrotorsion #lowbackpain #thegaitguys #gaitproblem

this is his left hip in full internal rotation. note that he does go past zero.

this is his left hip in full internal rotation. note that he does go past zero.

full internal rotation of the right hip; note he does not go past zero

full internal rotation of the right hip; note he does not go past zero

note the internal tibial torsion. a line dropped from the tibial tuberosity should go through the 2nd metatarsal or between the 2nd and 3rd.

note the internal tibial torsion. a line dropped from the tibial tuberosity should go through the 2nd metatarsal or between the 2nd and 3rd.

ditto for the keft

ditto for the keft

a line bisecting the calcaneus should pass between the 2nd and 3rd metatarsal shafts. If talar tosion was present, the rearfoot would appear more adducted

a line bisecting the calcaneus should pass between the 2nd and 3rd metatarsal shafts. If talar tosion was present, the rearfoot would appear more adducted

less adductus but still present

less adductus but still present

look at that long flexor response in compensation. What can you say about the quadratus plantae? NO bueno…

look at that long flexor response in compensation. What can you say about the quadratus plantae? NO bueno…

Ditto!

Ditto!

Keep your eyes up and your toes up...,And it doesn’t hurt to use your abs

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While out cross country skiing after a few inches of fresh fallen snow it dawned on me, especially when going uphill on my cross-country skis, lifting your toes up definitely pushes the head of the first metatarsal down and helps you to gain more purchase with the scales on the bottom of the skis. It also helps to press the center portion of the camber of the ski downward so that you can get better traction. Thinking about this further, lifting your toes up also helps you to engage your glutes to a greater degree.

Try this: stand comfortably with your knees slightly flexed. Lift up your toes leaving the balls of your feet on the ground. Do you feel the first metatarsal head going down and making better contact with the ground? Can you feel your foot tripod between the head of the first metatarsal, head of the fifth metatarsal and the calcaneus? Now let your toes go down. Squeeze your glute max muscles. You should still be able to fart so don’t squeeze the sphincter. You can palpate these muscles to see if you’re actually getting to them. You can do this by placing your hands on top of your hips with your fingers calling around forward like when your mom used to put her hands on her hips and yell at you. Now relax with your toes up again leaving the balls of your feet on the ground. Now engage your glutes. See how much easier it is?

Now stand with your feet flat on the ground and put your hands on your abs, specifically your external obliques. Now raise your right leg. Do you feel your external oblique engage? Now, lift your toes up leaving the balls of your feet on the ground. Now lift your leg. Do you feel how much more your abs engage?

Little tricks of the trade. That’s why you listen here and why your patients/clients come to see you. Now go out and do it!

Dr. Ivo, one of The Gait Guys

#gaitanalysis, #crosscountryskiing, #skiing, hallux, #engage, #abs

Barefoot running is Barefoot running. There is no substitute

umage source: https://commons.wikimedia.org/wiki/File:06patriotsrun5.jpg

umage source: https://commons.wikimedia.org/wiki/File:06patriotsrun5.jpg

There is nothing quite like running barefoot .. literally ..

There are few studies which examined barefoot versus simulated barefoot versus shod running and this is one of them (1). The forefoot strike pattern and shorter stride length (or increased cadence, provided velocity is constant) often associated with barefoot running, as well as simulated barefoot running seems, to decrease vertical impact loading rates, depending upon the angle of the foot on landing and seem desirable for decreasing injury risk (2-4).

Running barefoot has the greatest amount of ankle dorsiflexion, plantar flexion and thus total range of motion with the knee flexion angle being the least when comparing it to shod and stimulated barefoot running. stride length was shorter and cadence increased, as was suspected and has been reported in many other studies. It is surprising that and stimulated barefoot running, the forefoot strike was there however cadence and stride length did not really change.

In short, the runners were able to simulate some elements of barefoot running, but they did not completely mimic it.

Want to know more? Join us this Wednesday on onlinece.com: Biomechanics 303 for a lively discussion of barefoot running and more. 8 EST, 7 CST, 6 MST, 5PST

  1. Leblanc M, Ferkranus H. Lower Extremity Joint Kinematics of Shod, Barefoot, and Simulated Barefoot Treadmill Running. Int J Exerc Sci. 2018;11(1):717-729.

    link to FREE FULL TEXT: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6033505/#b31-ijes-11-1-717

  2. Shih Y, Lin KL, Shiang TY. Is the foot striking pattern more important than barefoot or shod conditions in running? Gait Posture. 2013;88(4):116–120. [PubMed]

  3. Hobara H, Sato T, Sakaguchi M, Nakazawa K. Step frequency and lower extremity loading during running. Int J Sports Med. 2012;2012;33:310–313. [PubMed]

  4. Thompson MA, Lee SS, Seegmiller J, McGowan CP. Kinematic and kinetic comparison of barefoot and shod running in mid/forefoot and rearfoot strike runners. Gait Posture. 2015;41:957–959. [PubMed]

Barefoot vs Shoes...It's about the strike pattern


Footnotes 7 - Black and Red.jpg

“The influence of strike patterns on running is more significant than shoe conditions, which was observed in plantar pressure characteristics. Heel-toe running caused a significant impact force on the heel, but cushioned shoes significantly reduced the maximum loading rate. Meanwhile, although forefoot running can prevent impact, peak plantar pressure was centered at the forefoot for a long period, inducing a potential risk of injury in the metatarsus/phalanx. Plantar pressure on the forefoot with RFS was lesser and push-off force was greater when cushioned shoes were used than when running barefoot.”


takeaways from the study?

  • forefoot strike reduces heel impact

  • rear foot strike reduces forefoot impact

  • forefoot strike increases and prolongs pressures (in shoes) on the forefoot which could potentially cause forefoot problems

  • cushioned shoes do not really change impact force but change (reduce) the rate of loading

  • in a forefoot strike, pressures are shifted more to the mid foot

want to know more? Join us this Wednesday, December 19th on online.com: Biomechanics 303







Sun XYang YWang LZhang XFu W. Do Strike Patterns or Shoe Conditions have a Predominant Influence on Foot Loading? J Hum Kinet. 2018 Oct 15;64:13-23. doi: 10.1515/hukin-2017-0205. eCollection 2018 Sep.

link to FREE FULL TEXT: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6231350/





The next time they have gait asymmetry, try changing out the insole...

or putting a textured one in there...or maybe putting a some sand or dirt in their shoe...

image credit: https://torange.biz

image credit: https://torange.biz

Textured insoles change (we like to think for the better) proprioceptive input and can improve balance and gait performance, both statically and dynamically. We have seen this in folks with parkinsons (1) as well as stroke (2), though it can be used in the elderly (3), in diabetes and neuropathy (4), as well as healthy individuals (5,6). Changes from postural stability, to changes in anterior/posterior sway, to medial/lateral sway, to step length and height, the research is there.

These results support the hypothesis that enhanced somatosensory feedback to the sensory system, both through the spinocerebellar and dorsal column pathways, as well as the vestibular system, results in an improved motor output (and most likely coordination) of gait.

  1. Qiu F, Cole MH, Davids KW, et al. Effects of textured insoles on balance in people with Parkinson's disease. PLoS One. 2013;8(12):e83309. Published 2013 Dec 12. doi:10.1371/journal.pone.00833

  2. Ma CC1, Rao N2, Muthukrishnan S3, Aruin AS4. A textured insole improves gait symmetry in individuals with stroke. Disabil Rehabil. 2017 Aug 7:1-5. doi: 10.1080/09638288.2017.1362477. [Epub ahead of print]

  3. Annino G1,2,3, Palazzo F2, Alwardat MS4, Manzi V5, Lebone P2, Tancredi V1,2,3, Sinibaldi Salimei P2,6,7, Caronti A2, Panzarino M2,3, Padua E2,3. Effects of long-term stimulation of textured insoles on postural control in health elderly. J Sports Med Phys Fitness. 2018 Apr;58(4):377-384. doi: 10.23736/S0022-4707.16.06705-0. Epub 2016 Sep 15.

  4. Paton J, Glasser S, Collings R, Marsden J. Getting the right balance: insole design alters the static balance of people with diabetes and neuropathy. J Foot Ankle Res. 2016;9:40. Published 2016 Oct 5. doi:10.1186/s13047-016-0172-3

  5. Steinberg N1, Tirosh O, Adams R, Karin J, Waddington G. Influence of Textured Insoles on Dynamic Postural Balance of Young Dancers. Med Probl Perform Art. 2017 Jun;32(2):63-70. doi: 10.21091/mppa.2017.2012.

  6. Collings R1, Paton J2, Chockalingam N3, Gorst T2, Marsden J2. Effects of the site and extent of plantar cutaneous stimulation on dynamic balance and muscle activity while walking. Foot (Edinb). 2015 Sep;25(3):159-63. doi: 10.1016/j.foot.2015.05.003. Epub 2015 May 11.

What did you notice? The Devil is in the details...

 Cavus foot? Loss of the transverse arch? Prominence of extensor tendons?

The question is: Why?

It’s about reciprocal inhibition. The concept, though observed in the 19th century, was not fully understood and accepted until it earned a Nobel prize for its creditor, Sir Charles Sherrington, in 1932. Simply put, when a muscle contracts, its antagonist is neurologically inhibited, So when your bicep contracts, your tricep is inhibited. This holds true whether you actively contract the muscle or if the muscle is irritated (causing contraction).

So how does this apply to this foot?

We see prominence of the extensor tendons (particularly the extensor digitorum brevis EDB; the longus would have caused extension at the distal interphalangeal joint). The belly of the muscle is visible, telling us that it is active. It is neurologically linked to the flexor digitorum brevis (FDB). This muscle, in turn, has slips which attach it to the abductor hallucis brevis (AHB) medially and the abductor digiti minimi (ADM) laterally. These muscles together form 2 triangles (to be discussed in another post) on the bottom of the foot, which lend to the stability of the foot and the arches, especially the transverse.

When the EDB fires, it inhibits the FDB, (which, in addition to flexing the MTP’s, assists in maintaining the arch). The EDB has an effect which drops the distal heads of the metatarsals as well (Hmm, think about all the people with met head pain) Now, look at the course of the tendons of the EDB. In a cavus foot, there is also a mild abductory moment, which flattens the arch. Conversely, the FDB in a cavus foot would serve to actually increase the arch, and would have a ,mild adductory moment. Net result? A flattened transverse arch.

Now look at the Flexor digitorum longus, overactive in tbis foot (as evidenced by the flexion of the distal interphalangeal joints, mild adduction of the toes (due to the change of direction of pull in a cavus foot) and lowering of the met heads due to hyperextesnion at the MTP joints ). This mm is reciprocally linked with the extensor digitorum longus. The prominence of the extensor tendons is do to increased activity of the EDB (go ahead, extend all your fingers and look at the tendons in your hand. Now flex the  DIP and IP joints and extend the MTP; see how they become more prominent?).

Reciprocal inhibition. It’s not just for dinner anymore…

We are and remain; The Gait Guys

How is your foot is connected to your butt....?

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If you have been following us for any length of time, you have heard us talk about how the lower kinetic chain is connected, how ankle rocker effects hip extension and how important hallux (great toe) extension is. 

What can we conclude from this study?

toe spreading exercises are important for reducing navicular drop (and thus mid foot pronation, at least statically)
In addition to increased abductor hallucis recruitment in ascending and descending stairs, when hip external rotation exercises were added along with toe spreading exercises folks had more recruitment of the vastus medialis (a closed chain external rotator of the leg and thigh)
 
Keep in mind:

the exercises given were all non weight bearing and open chain for the external rotators. Imagine what might have happened if they were both closed chain AND weight bearing!
They concentrated on the effects of toe spreading (AKA  lift/spread/reach) on the abductor hallucis. It also has far reaching effects on the dorsal interossei, long and short extensors of the toes. 

Abstract: The purpose of the present study was to examine the effects of toe-spread (TS) exercises and hip external rotator strengthening exercises for pronated feet on lower extremity muscle activities during stair-walking. [Subjects and Methods] The participants were 20 healthy adults with no present or previous pain, no past history of surgery on the foot or the ankle, and no foot deformities. Ten subjects performed hip external rotator strengthening exercises and TS exercises and the remaining ten subjects performed only TS exercises five times per week for four weeks. [Results] Less change in navicular drop height occurred in the group that performed hip external rotator exercises than in the group that performed only TS exercises. The group that performed only TS exercises showed increased abductor hallucis muscle activity during both stair-climbing and -descending, and the group that performed hip external rotator exercises showed increased muscle activities of the vastus medialis and abductor hallucis during stair-climbing and increased muscle activity of only the abductor hallucis during stair-descending after exercise. [Conclusion] Stair-walking can be more effectively performed if the hip external rotator muscle is strengthened when TS exercises are performed for the pronated foot.

Goo YM, Kim DY, Kim TH. The effects of hip external rotator exercises and toe-spread exercises on lower extremity muscle activities during stair-walking in subjects with pronated foot. J Phys Ther Sci. 2016 Mar;28(3):816-9. doi: 10.1589/jpts.28.816. Epub 2016 Mar 31. 
link to  FREE FULL TEXT: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4842445/