Yep, these shoes stink for this gal...


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

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.


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.


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

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.


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

Whaddaya Think of these Shoes?

Would you put YOUR patient/client/own feet in them?

Dr Ivo Waerlop, one of The Gait Guys, discusses a common manufacturers defect to look out for, especially in people with rear foot problems. You have to watch out for manufacturers defects in shoes : )


Biomechanics 308 5 PST, 6 MST, & CST, 8 EST

#gait #thegaitguys #shoeproblem #manufacturersdefect#footproblem

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

Subtle clues to an LLD?

Leg length discrepancies, whether their functional anatomical, have biomechanical consequences north of the foot. This low back pain patient exhibited 2 signs. Can you tell what they are?

can you see the difference ?

can you see the difference ?

how about now?

how about now?

compare right to left

compare right to left

compare right to left

compare right to left

can you see the difference in the Q angles?

can you see the difference in the Q angles?

Look at the first picture and noticed how the left knee is hyper extended compared to the right. Sometimes we see flexion of this extremity. This is to "functionally shorten" that extremity.

Now look at the Q angles. Can you see how the left QL angle is greater than the right? This usually results from a long-term leg length discrepancy where the body is attempting to compensate by increasing the valgus angle of that knee, effectively shortening the extremity.

Dr Ivo Waerlop, one of The Gait Guys

#subtle #clues #LLD #leglengthdiscrepancy #leglengthinequality #thegaitguys #gaitabnormality

What does a pedograph of a person with hallux limitus look like?


Take a good look at the pedographs above. Can you figure out which side has the hallux limitus from the pictures? 

You would think that with hallux limitus there would be increased printing over the distal phalanx of great toe and possibly over the distal metatarsal as seen in the print of the right foot. This would make sense as if you have limited motion here and the pressure will be more forward. However, often times Hallux limitus is painful and the patient develops a compensation to NOT load the joint, as we see on the print of the left foot. We see the lack of printing under the first metatarsal head and increased printing laterally in the foot from avoidance of that joint. Also notice a slight increased printing in the right heel teardrop (hash marks are more filled in) and slight widening of it anteriorly. He has a right sided leg length discrepancy and we would normally expect an increased amount of pronation on the longer leg side, however because of the weight shift to the left we are seeing increased pronation on the right. Now, with this valgus moment of the right foot do you understand why the printing is so heavy under the first metatarsal and distal phalanx. Note also the increased printing at the distal phalanx of toes number two, three and five on the right hand side in an attempt to stabilize as his center of gravity shifts to the right.

And now you know!

Dr Ivo, one of The Gait Guys

#halluxlimitis, #gaitanalysis, #pedograph, #leglengthdiscrepancy, #LLD

Whoa! Dangerous shoes ahead....


Holy smokes ! Can you believe this?

Take a look at these BRAND NEW, just out of the box pair of Brooks Cadence shoes. We do not usually see many manufacturer defects from this brand. Looks like someone might have been asleep at the “upper goes on the midsole” machine

Check out the varus cant to the rearfoot of the right shoe. Now look at the forefoot valgus cant to the left shoe. This would not be a great shoe for someone who has too much rear foot eversion and midfoot pronation on the right and and uncompensated forefoot valgus on the left, but we do not think it was designed for that specific, small niche market.

Think of the biomechanical implications on a "neutral" foot. Placing the right rear foot in varus would effectively halt or slow pronation in the rear foot and midfoot of that foot. This could be a good thing for an over pronator but, in a neutral foot, this would cause them to toe off in supination on that side resulting in low gear push off and biomechanical insufficiency, not to mention the increased external rotation of the lower extremity and lack of shock absorption from 1 of the 4 mechanisms of shock absorption left (mid foot pronation, ankle dorsiflexion, knee flexion, thumb flexion, contralateral drop of the pelvis). Now, imagine if that same person had internal tibial torsion. Talk about placing the knee outside of the sagittal plane ! Can you say macerated meniscus?

And now the left shoe. Look at the valgus cant! If you had and uncompensated forefoot valgus, where the forefoot is everted with respect to the rear foot or a forefoot varus, where they had adequate range of motion to allow the first ray to descend, then this could be a good thing, otherwise they are toeing off in too much pronation. This could be a real problem for a midfoot pronator or someone with large amounts of external tibial torsion, because they commonly toe off in too much pronation and low gear to begin with, as this shoe would accelerate pronation from midfoot to the forefoot

The bottom line? Look at your patients/clients shoes, as well as your own before purchasing them and examined for manufacturer defects. The upper should sit squarely on the midsole and the shoe should not rock or tip from side to side.


A great paper on Hallux Limits

Don't let the title fool or dissuade you. 

Here is a great paper to support the post earlier this week on hallux limitus. 

Plantar pressure distribution in older people with osteoarthritis of the first metatarsophalangeal joint (hallux limitus/rigidus)

No surprise that the study found folks with osteoarthritis of the the 1st MPJ had greater maximum force and peak pressures under the hallux as well as the lesser toe than controls. 

BUT here is one of the gems from the study: " However, the plantar pressure changes observed in this study can be explained using the concept of high- and low-gear push off described by Bojson-Moller. This model suggests that there are two metatarsal axes through which propulsion may occur; a transverse axis connecting the first to second metatarsal heads, and an oblique axis connecting the second to fifth metatarsal heads. In the presence of normal first MPJ motion, a ‘‘high-gear’’ push- off occurs through the transverse metatarsal axis, resulting in an efficient transfer of bodyweight. In the presence of restricted first MPJ motion, propulsion through the transverse axis is not possible. Subsequently, a ‘‘low-gear’’ push-off occurs through the oblique axis, which subjects the lateral forefoot and toes to increased loading and results in hyperextension of the interphalangeal joint of the hallux prior to toe-off."

Zammit, G. V., Menz, H. B., Munteanu, S. E. and Landorf, K. B. (2008), Plantar pressure distribution in older people with osteoarthritis of the first metatarsophalangeal joint (hallux limitus/rigidus). J. Orthop. Res., 26: 1665–1669. doi:10.1002/jor.20700.    



What do we have here and what type of shoe would be appropriate?

You are looking at a person with a fore foot varus. This means that the fore foot (ie, plane of the metatarsal heads) is inverted with respect to the rear foot (ie, the calcaneus withe the subtalar joint in neutral). Functionally translated, this means that they will have difficulties stabilizing the medial tripod (1st MET head) to the ground making the forefoot and arch unstable and likely rendering the rate and degree of pronation increased.

The incidence of this condition is 8% of 116 female subjects (McPoil et al, 1988) and 86% of 120 male and female subjects (Garbalosa et al, 1994), so it seems to happen happen more in males. We think this second number is inflated and those folks actually had a forefoot supinatus, which is much more common.

Fore foot varus occurs in 3 flavors:

  • compensated
  • uncompensated
  • partially compensated

What is meant by compensated, is that the individual is able to get the head of the 1st ray to the ground completely (compensated), partially, or, when not at all, uncompensated.What this means from a gait perspective ( for partially and uncompensated conditions) is that the person will pronate through the fore foot to get the head of the 1st ray down and make the medial tripod of the foot (ie, they pronate through the subtalar joint to allow the 1st metatarsal to contact the ground). This causes the time from mid-stance to terminal stance to lengthen and will inhibit resupination of the foot. 

Today we are looking at a rigid, uncompensated forefoot varus, most likely from insufficient talar head derotation during fetal development and subsequent post natal development. They will not get to an effective foot tripod. They will collapse the whole foot medially. These people look like severely flat-footed hyperpronators.

So, what do you do and what type of shoe is appropriate? Here’s what we did:

  • try and get the 1st ray to descend as much as possible with exercises for the extensor hallucis brevis and short flexors of the toes (see our videos on youtube)
  • create more motion in the foot with manipulation, massage mobilization to optimize what is available
  • strengthen the intrinsic muscles of the feet (particularly the interossei)
  • increase strength of the gluteus maximus and posterior fibers of the gluteus medius to slow internal rotation of the leg during initial contact to midstance
  • put them in a flexible shoe for the 1st part of the day, to exercise the feet and a more supportive; medially posted (ideally fore foot posted) shoe for the latter part of the day as the foot fatigues
  • monitor his progress at 3-6 month intervals
  • a rigid orthotic will likely not help this client and they will find it terribly uncomfortable because this is a RIGID deformity for the most part (the foot will not accommodate well to a corrective orthotic. Besides, the correction really has to be made at the forefoot anyways. 

Lost? Having trouble with all these terms and nomenclature? Take our national shoe fit program, available by clicking here.

The Gait Guys. Uber foot geeks. Separating the wheat from the chaff, with each and every post.

The Q angle and Kids: The Basics

Screen Shot 2017-05-01 at 3.37.08 PM.png

Genu valgum in kids: What you need to know

We have all seen this. The kid with the awful “knock knees”.  It is a Latin word “which means “bent” or “knock kneed”. It appears to have 1st been used in 1884.

This condition, where the Q angle angle exceeds 15 degrees, usually presents maximally at age 3 and should resolve by age 9. It is usually physiologic in development due to obliquity of the femur, when the medial condyle is lower than the lateral. Normal development and weight bearing lead to an overgrowth of the medial condyle of the femur. This, combined with varying development of the medial and lateral epiphysies of the tibial plateau leads to the valgus development. Gradually, with increased weight bearing, the lateral femoral condyle (and thus the tibial epiphysis) bear more weight and this appears to slow, and eventually reverse the valgum.

Normal knee angulation usually progresses from 10-15 degrees varus at birth to a maximal valgus angle of 10-15 degreesat 3-3.5 years (see picture).  The valgus usually decreases to an adult angle of 5-7 degrees.  Remember that in women, the Q angle should be less than 22 degrees with the knee in extension and in men, less than 18 degrees. It is measured by measuring the angle between the line drawn from the ASIS to the center of the patella and one from the center of the patella through the tibial tuberosty, while the leg is extended.

Further evaluation of a child is probably indicated if:

  • The angle is greater than 2 standard deviations for their age (see chart) 
  • If their height is > 25th percentile 
  • If it is increasing in severity 
  • If it is developing asymmetrically

Management is by serial measurement of the intermalleolar distance (the distance between ankles when the child’s knee are placed together) to document gradual spontaneous resolution (hopefully). If physiologic genu valgum persists beyond 7-8 years of age, an orthopaedic referral would be indicated but certainly intervention with attempts at corrective exercises and gait therapy should be employed. Persistence in the adult can cause a myriad of gait, foot, patello femoral and hip disorders, and that is the topic on another post.

Promotion of good foot biomechanics through the use of minimally supportive shoes, encouraging walking on sand (time to take that trip to the beach!), walking on uneven surfaces (like rocks, dirt and gravel), gentle massage (to promote muscle facilitation for those muscles which test weak (origin/insertion work) and circulation), gait therapeutic exercises and acupuncture when indicated, can all be helpful.

Do you know SQUAT? Have you seen SQUAT? Have patients/clients that LIKE to squat? Seen a foot that looks like this? Can you say REARFOOT VALGUS?

 "Significant changes in lower limb kinematics may be observed during bilateral squatting when rearfoot alignment is altered. Shoe pitch alone may significantly reduce peak pronation during squatting in this population, but additional reductions were not observed in the subtalar neutral position. Further research investigating the effects of footwear and the subtalar neutral position in populations with lower limb pathology is required."
So, what does this study tell us?

when rearfoot aliment changes, so do the kinematics (duh)
the surface (tilted into varus or inversion) or shoes (which are medially posted) can make or break the man (or women) when it comes to "peak" pronation (we knew that already; confirmation is always nice)
inverting the rearfoot can change ankle dorsiflexion (read "ankle rocker"); inverting the rearfoot seems to reduce it
inverting the rearfoot can change knee flexion; inverting the rearfoot seems to increase knee flexion
inverting the rearfoot can change hip abduction (and thus knee valgus); reducing it

Learn about the gait kinematics and clinical findings associated with this foot type, along with video clip examples and always entertaining discussion with us tomorrow night on Biomechanics 308: Focus on the Rear Foot.  5PST, 6MST, 7 CST, 8EST

Power V, Clifford AM. The Effects of Rearfoot Position on Lower Limb Kinematics during Bilateral Squatting in Asymptomatic Individuals with a Pronated Foot Type. J Hum Kinet. 2012 Mar;31:5-15. doi: 10.2478/v10078-012-0001-0. Epub 2012 Apr 3.

#rearfootvalgus #squat #foottype

2012 Mar;31:5-15. doi: 10.2478/v10078-012-0001-0. Epub 2012 Apr 3.

The Effects of Rearfoot Position on Lower Limb Kinematics during Bilateral Squatting in Asymptomatic Individuals with a Pronated Foot Type.

Power V1, Clifford AM.

Author information


Clinicians frequently assess movement performance during a bilateral squat to observe the biomechanical effects of foot orthotic prescription. However, the effects of rearfoot position on bilateral squat kinematics have not been established objectively to date. This study aims to investigate these effects in a population of healthy adults with a pronated foot type. Ten healthy participants with a pronated foot type bilaterally (defined as a navicular drop >9mm) performed three squats in each of three conditions: barefoot, standing on 10mm shoe pitch platforms and standing on the platforms with foam wedges supporting the rearfoot in subtalar neutral. Kinematic data was recorded using a 3D motion analysis system. Between-conditions changes in peak joint angles attained were analysed. Peak ankle dorsiflexion (p=0.0005) and hip abduction (p=0.024) were significantly reduced, while peak knee varus (p=0.028) and flexion (p=0.0005) were significantly increased during squatting in the subtalar neutral position compared to barefoot. Peak subtalar pronation decreased by 5.33° (SD 4.52°) when squatting on the platforms compared to barefoot (p=0.006), but no additional significant effects were noted in subtalar neutral. Significant changes in lower limb kinematics may be observed during bilateral squatting when rearfoot alignment is altered. Shoe pitch alone may significantly reduce peak pronation during squatting in this population, but additional reductions were not observed in the subtalar neutral position. Further research investigating the effects of footwear and the subtalar neutral position in populations with lower limb pathology is required.

One of life's great mysteries....Some folks will do what they want anyway....

The origins of the species, gravity and women...Just a few of life mysteries. Reading this article (1) made us sad in many ways. It's like smoking. You know it's bad for you but you keep doing it. Why? The mystery remains to us.

Vanity seems to often trump biomechanics, as we see in pencil skirts (see our post here), droopy pants (see here)  and high heels (here).

Yet, here is yet another study about women, heels and bunion surgery. 

"Almost two thirds (31) of the 50 patients who said they wanted to go back to wearing heels after surgery did so, and 24 of these women said their postoperative use equaled or exceeded the frequency of their preoperative wear. There were no differences between pre- and postoperative heel heights.

In the study, women older than 65 years were more likely than younger women to report high-heel use prior to hallux valgus surgery.

However, 58.5% of study participants reported difficulty with heel wear, and 13.9% said they had significant restriction, and couldn’t wear anything without pain but custom orthopedic shoes or slippers. Most women (86%) were able to return to comfortable shoes after surgery with minimal or no discomfort; 27.7% said their footwear choice was unrestricted, meaning they could wear both comfortable shoes and heels with minimal discomfort. The 23 women older than 65 years were twice as likely to report significant restriction as those in the younger cohort; compared by operative type, patients who had the most extensive procedures had the highest rates of restriction. The findings were published in June by the World Journal of Methodology. (2)"

Bunions are believed to be caused by an inability to anchor the 1st ray and the untoward action of the adductor hallucis, acting from the transverse and oblique insertions more proximally on the foot, make the hallux head west. This is under the purview of the peroneus longus, extensor hallucis brevis as well as the short flexors of the lesser toes (see here).

The components of supination are plantar flexion, inversion and adduction. Why would you continue to wear a shoe with a narrow toe box that forces the big toe medially and that puts you in plantar flexion? We won't even begin to talk about the loss of ankle rocker.....

We guess folks will continue to do what they will do....


1. Robinson C, Bhosale A, Pillai A. Footwear modification following hallux valgus surgery: The all-or-none phenomenon. World J Methodol 2016;6(2):171-180.


The Knee and Macerating Menisci

Take a good look at the above 2 slides.

Notice that, during pronation, there is a medial rotation of the lower leg and thigh. We remember that, during pronation, the talus plantar flexes, adducts, and everts. This anterior translation and medial rotation of the talus causes the tibia and subsequently the femur to follow. This, if everything is working right, results in medial rotation of the knee.

From the slides, it should also be evident that the medial condyle of the femur and a medial tibial plateau are larger than the lateral. This allows for an increased amount of internal and external rotation of the knee. We remember that the meniscus, like a washer, is between the tibia and femur. We if you think about this kinematically, it would make sense that the tibia, during pronation (which occurs from initial contact to mid stance) would have to rotate faster than the femur otherwise the meniscus would be caught "in between". If there is a mismatch in timing, the meniscus is "caught in the middle", which causes undue stress and can cause fraying, degeneration, etc.

Likewise, during supination (from mid stance to pre swing) the femur must externally rotate faster then the tibia, otherwise we see this same "mismatch". This is a scenario we commonly see in folks who over pronate at the mid foot and remain in pronation for too omg a period of time. 

We think of pronation as being initiated from the movement described above by the talus, and it is attenuated by the popliteus muscle as well as some of the deep flexors of the foot, which fire mostly during stance phase. You will notice that the popliteus  is eccentrically contracting at this point.

Supination, initiated by swing phase of the opposite leg and momentum, is assisted by concentric contraction of the popliteus muscle, internal rotation of the pelvis on the stance phase leg, contraction of the vastus medialis, deep flexors of the foot and peroneii.

Taking moment to "wrap your head around" this concept. Now you can see how complicated it can be when we started to throw in femoral and tibial torsions as well as possibly some orthotic therapy. For example, in an individual with internal tibial torsion, if you do not valgus post the forefoot of the orthotic, the knee is placed at outside the sagittal plane in external rotation further by the orthotic and this thwarts the function of his mechanism, leaving the meniscus holding the bag. 

Know your anatomy and know what is supposed to be firing when, your patients and clients knees depend on it!



Sometimes you need to run that valgus post clear back to the heel!

A valgus post assists in pronation. Some fols have modereate to severe internal tibial torsion and need to be able to pronate more to get the knee into the saggital plane for patello femoral conflicts. They usually run from the tail of the 5th metatarsal forward, but sometimes need to run it clear back to the heel to get enough pronation to occur.