Simple Foot Exercises are effective!

Conclusion “These results suggest that the toe spread out (TSO) exercise can be recommended for preventing or correcting HV deformity at an early stage.”

We know and teach that foot exercises work. Here is a nice objective paper (click underlined for abstract) on two exercises we prescribe often.

Here is our variation of the TSO exercise we call the “Lift, Spread and Reach” exercise

Stand comfortably with your feet about shoulder width apart

Stand on your foot tripod with your toes extended. Concentrate on feeling pressure at the center of the calcaneus, the head of the 1st metatarsal and the head of the 5th metatarsal

Lift your toes as high as possible

Spread out (abduct) your toes as much as possible

Reach forward with your toes as far as possible

Place your toes back don on the ground as flat as possible.

repeat 10 X

You can augment the exercise with a rubber band around the toes to provide resistance after you can perform the exercise competently.

Happy exercising!

Ivo and Shawn

Kim MH1, Kwon OY, Kim SH, Jung DY.: Comparison of muscle activities of abductor hallucis and adductor hallucis between the short foot and toe-spread-out exercises in subjects with mild hallux valgus

J Back Musculoskelet Rehabil. 2013;26(2):163-8. doi: 10.3233/BMR-2012-00363.

The partial truth about the Foot Tripod. The HEXApod.

The gait guys have talked about the foot tripod for a very long time. But the truth of the matter is that it is really a HEXApod. HEXA means 6. And when the foot is properly orientated and engaged on the ground, the 5 metatarsal heads and the heel should all be engaged with the ground, truly making it an asymmetrical hexapod. In an ideal scenario, the foot would be most stable if it looked like the strange symmetrical hexapod above with the contact points equally distributed around a center point. But that is not the human foot and this version of a hexapod is far simpler and likely inferior to the foot hexapod when human locomotion is to be attempted. The human foot is engineering marvel when it works properly.  

Perhaps the best example of what I mean by the foot being a HEXApod is in the pressure diagram above. In that first picture, on the right of that picture, we see multiple pressure points under the metatarsal heads of the right foot.  Minus the missing 1st metatarsal head pressure point (taken over by increased flexor hallucis longus activity represented by increased pressure at the big toe),  this pretty much confirms that the foot is not a tripod, rather a hexapod. The theory of the tripod, the 1st and 5th metatarsal heads and the heel, is only crudely accurate and honest. In this picture case, this person has increased lateral foot weight bearing (possibly why the 1st MET head pressure is absent) and possibly represented by pressure under the base of the 5 metatarsal. This is not normal for most people and if this person could get the 1st MET head down, they might even have a HEPTApod foot structure because of the 5th metatarsal base presentation (which sometimes represents peroneal muscle weakness). 

Where did we lead you astray after all these years of “tripod” talk ? We have always discussed the foot tripod. We have always discussed the imperative need to keep the limb’s plumb line forces within the area represented by the tripod.  If your forces fall more laterally within the tripod, as in this first discussed picture, one is at increased risk of inversion events and the myriad of compensations within the entire body that will occur to prevent that inversion. So again, why the tripod?  Well, it is easier to understand and it serves our clients well when it comes to finding active foot arch restoration as seen in this video of ours here.  But, the truth of the matter is that all of the metatarsal heads should be on the ground. The 2nd METatarsal is longer, the 3rd a little shorter, and the 4th and 5th even a little short than those. With the 1st MET shorter, these 5 form a kind of parabolic arc if you will. Each metatarsal head still should contact the ground and then each of those metatarsals should be further supported/anchored by their digits (toes) distally.  So the foot is actually more truly a HEXAPOD. Take the old TRIPOD theory we have always spoken about and extend a curved line beyond the forefoot bipod points (1st and 5th metatarsals) to incorporate contact points on the 2, 3 and 4th metatarsal heads. These metatarsals help to form the TRANSVERSE arch of the foot. It is this transverse arch that has given us the easily explainable foot TRIPOD because if a line is drawn between just the shorter 1st and 5th metatarsals, we do not see contact of the 2-4 metatarsal heads when we only look for pressure between these two bipod landmarks, but the obvious truth is that the 2-4 metatarsals are just longer and extend to the ground further out beyond this theoretical line drawn between the 1st and 5th MET heads.   

So, the foot is a HEXAPOD. Make no mistake about it. It is more stable than a tripod because there are more contact points inside the traditionally discussed foot tripod model. And frankly, the tripod theory is just a lie and just too fundamentally simple, unless you are an American 3 toed woodpecker.

Dr. Shawn Allen,     www.doctorallen.co

one of the gait guys

Keeping it Objective.

For clinicians and some die hard foot geeks, we often like to keep things objective. What could be more objective than an angular measurement? A few important measurements when examining or radiographing feet can give us information about clinical decision making (not that we suggest radiographs for mensuration purposes unless you are a surgeon, but when they are already available, why not put them to good use ?). When things fall outside the accepted range, or appear to be heading that way, these numbers can help guide us when to intervene. 

Hallux valgus refers to the big toe headed west (or east, depending on the foot and your GPS). In other words, the proximal and distal phalanyx of the great toe (hallux) have an angle with the 1st metatarsal shaft of typically > 15 degrees. This angle, called the Hallux Valgus Angle (HVA above) is used to judge severity, often for surgical intervention purposes but can guide conservative management as well. 

Metatarsus Primus Varus (literally, varus deformity of the 1st metatarsal) often accompanies Hallux Valgus. It describes medial deviation of the 1st metatarsal shaft, greater than 9 degrees. This angle is called the intermetatarsal angle and is measured by the angle formed by lines drawn parallel along the long axis of the 1st and 2nd metatarsal shafts. 

One other measurement is the Distal Metatarsal Articular Angle, which measures the angle between the metatarsal shaft and the base of the distal articular cap (ie, where the cartilage is) of the 1st metatarsal. This typically should be less than 10 degrees, preferably less than 6 degrees. Remember, these are static angles, things can change with movement, engagement, weight bearing strategies and shoes. What you see statically does not always predict dynamic angles and joint relationship.s

Are you doing surgery? Perhaps, as a last resort. Hallux valgus and metatarsus primus varus can be treated conservatively.

How do you do that?

The answer is both simple and complex.

The simple answer is: anchor the head of the 1st ray and normalize foot function. This could be accomplished by:

  • EHB exercises to descend the head of the 1st metatarsal
  • exercise the peroneus longus, to assist in descending the head of the 1st metatarsal
  • short flexor exercises, such as toe waving, to raise the heads of the lesser metatarsals relative to the 1st
  • work the long extensors, particularly of the lesser metatarsals to create balance between the flexors and extensors
  • consider using a product like “Correct Toes” to normalize the pull of the muscles and physically move the proximal and distal phalanyx of the hallux
  • wear shoes with wide toe boxes, to allow the foot to physically splay
  • consider using an orthotic with a 1st ray cut out, to help descend the head of the 1st metatarsal

This is by no means an exhaustive list and you probably have some ideas of your own. 

The complex answer is that in the above example, we have only included conservative interventions for the foot and have not moved further up the kinetic (or neurological chain). Could improving ankle rocker help create more normal mechanics? Would you accomplish this by working the anterior leg muscles, the hip extensors, or both? Could a weak abdominal external oblique be contributing? How about a faulty activation pattern of the gluteus medius? Could a congenital defect or genetic be playing a role? We have not asked “What caused this to occur in the 1st place?”

Examine your patients and clients. Understand the biomechanics of what is happening. Design a rehab program based on your findings. Try new ideas and therapies. it is only through our failures that we can truly learn.

The Gait Guys

references used:

http://www.bjjprocs.boneandjoint.org.uk/content/90-B/SUPP_II/228.3

http://www.slideshare.net/ANALISIS/hallux-valgus-2008-pp-tshare

http://www.orthobullets.com/foot-and-ankle/7008/hallux-valgus

http://www.slideshare.net/bahetisidharth/hallux-valgus-31768699?related=1

When the big guy heads medially….Game Changer

Lately we have been seeing a lot of bunions (hallux valgus). While doing some research on intermetatarsal angles (that’s for another post) we came across the nifty diagram you see above. 

Regardless of the cause, as the 1st metatarsal moves medially, there are biomechanical consequences. Lets look at each in turn. 

  • the EHB (extensor hallucis brevis) axis shifts medially. this muscle, normally an extensor of the proximal phalanyx, now becomes more of an abductor of the hallux. It’s secondary action of assisting the descent of the head of the 1st metatarsal no longer happens and it actually moves the base of the proximal phalanyx posteriorly, altering the axis of centration of the joint, contributing to a lack of dorsiflexion of the joint and a hallux limitus
  • Abductor hallucis becomes more of a flexor, as it moves to the plantar surface of the foot. Remember, a large percentage of people already have this muscle inserting more on the plantar surface of the foot (along with the medial aspect of the flexor hallucis brevis), so in these folks, it moves even more laterally, distorting the proximal phalanx along its long axis (ie medially) see this post here for more info
  • Flexor hallucis brevis moves more laterally. Remember this muscle houses the sesamoid bones before inserting onto the base of the proximal phalannx; the medial blending with the abductor hallucis and the lateral with the adductor hallucis. Because the sesamoid bones have moved laterally, they no longer afford this muscle the mechanical advantage they did previously and the axis of motion of the 1st metatarsal phalangeal joint moves dorsally and posterior, contributing to limited dorsiflexion of that joint and a resultant hallux limitis. The lateral movement of the sesamoids also tips the long axis of the 1st metatarsal and proximal phalanyx into eversion. In addition, the metatarsal head is exposed and is subject to the ground reactive forces normally tranmittted through the sesamoids; often leading to metatarsalgia. 
  • Adductor hallucis: this muscle now has a greater mechanical advantage  and because the head of the 1st ray is not anchored, acts to abduct the hallux to a greater degree. The now everted position of the hallux contributes to this as well

As you can see, there is more to the whole than the sum of the parts. Bunions have many biomechanical consequences, and these are only a small part of the big picture. Take you time, learn your anatomy and examine everything that has a foot!

See you in the shoe isle…

Ivo and Shawn

pictures from: http://www.orthobullets.com/foot-and-ankle/7008/hallux-valgus and http://www.stepbystepfootcare.com/faqs/nakedfeet/

When the big guy heads medially….Game Changer

Lately we have been seeing a lot of bunions (hallux valgus). While doing some research on intermetatarsal angles (that’s for another post) we came across the nifty diagram you see above. 

Regardless of the cause, as the 1st metatarsal moves medially, there are biomechanical consequences. Lets look at each in turn. 

  • the EHB (extensor hallucis brevis) axis shifts medially. this muscle, normally an extensor of the proximal phalanyx, now becomes more of an abductor of the hallux. It’s secondary action of assisting the descent of the head of the 1st metatarsal no longer happens and it actually moves the base of the proximal phalanyx posteriorly, altering the axis of centration of the joint, contributing to a lack of dorsiflexion of the joint and a hallux limitus
  • Abductor hallucis becomes more of a flexor, as it moves to the plantar surface of the foot. Remember, a large percentage of people already have this muscle inserting more on the plantar surface of the foot (along with the medial aspect of the flexor hallucis brevis), so in these folks, it moves even more laterally, distorting the proximal phalanx along its long axis (ie medially) see this post here for more info
  • Flexor hallucis brevis moves more laterally. Remember this muscle houses the sesamoid bones before inserting onto the base of the proximal phalannx; the medial blending with the abductor hallucis and the lateral with the adductor hallucis. Because the sesamoid bones have moved laterally, they no longer afford this muscle the mechanical advantage they did previously and the axis of motion of the 1st metatarsal phalangeal joint moves dorsally and posterior, contributing to limited dorsiflexion of that joint and a resultant hallux limitis. The lateral movement of the sesamoids also tips the long axis of the 1st metatarsal and proximal phalanyx into eversion. In addition, the metatarsal head is exposed and is subject to the ground reactive forces normally tranmittted through the sesamoids; often leading to metatarsalgia. 
  • Adductor hallucis: this muscle now has a greater mechanical advantage  and because the head of the 1st ray is not anchored, acts to abduct the hallux to a greater degree. The now everted position of the hallux contributes to this as well

As you can see, there is more to the whole than the sum of the parts. Bunions have many biomechanical consequences, and these are only a small part of the big picture. Take you time, learn your anatomy and examine everything that has a foot!

See you in the shoe isle…

Ivo and Shawn

pictures from: http://www.orthobullets.com/foot-and-ankle/7008/hallux-valgus and http://www.stepbystepfootcare.com/faqs/nakedfeet/

Spanking the orthotic: The effects of hallux limitus on the foot’s longitudinal arch.

But the issues do not stop at the arch. If you have been with us long enough, you will have read about the effects of the anterior compartment (namely the tibialis anterior, extensor digitorum and hallucis and peroneus tertius muscles) strength and endurance on the arch.

Here we have a very troubled foot. This foot has undergone numerous procedures, sadly. Today we will not talk about the hallux varus you see here, a virtual unicorn in practice  (and acquired in this case) nor do we want to discuss the phalangeal varus drift. We want to draw your attention to the obvious impairment of the 1st MTP (metatarsophalangeal joint) dorsiflexion range.  You can see the large dorsal crown of osteophytes, a dorsal buttress to any hallux dorsiflexion.  There is under 10 degrees of dorsiflexion here, not even enough worth mentioning.  We have said it many times before, if you lose a range at one joint usually that range has to be accommodated for proximal or distal to the impaired joint. This is a compensation pattern and you can see it here in the hallux joints themselves.

Here you can see that some of the dorsiflexion range has been acquired in the proximal phalangeal joint.  We like to call this “banana toe” when explaining it to patients, it is a highly technical term but you are welcome to borrow it. This occurred because the joint was constantly seeing the limitation of dorsiflexion of the 1st MTP joint and seeing, and accommodating to, the demands of the need for more dorsiflexion at toe off. 

But, here is the kicker. You have likely seen this video of ours on Youtube on how to acquire a foot tripod from using the toe extensors to raise the arch.  Video link here  and here.  Well, in his patient’s case today, they have a limitation of 1st MTP dorsiflexion, so the ability to maximally raise the arch is impaired. The Windlass mechanism is broken; “winding” of the plantar fascia around the !st MTP mechanism is not sufficiently present. Any limitations in toe extension (ie dorsiflexion) or ankle dorsiflexion will mean that :

1. compensations will need to occur

2. The Windlass mechanism is insufficient

3. gait is impaired at distal swing phase and toe off phases

4. the anterior compartment competence will drop (Skill, endurance, strength) and thus injury can be more easily brought to the table.

In this patient’s case, they came in complaining of burning at the top of the foot and stiffness in the anterior ankle mortise area.  This would only come on after a long brisk walk.  If the walk was brisk yet short, no problems. If the walk was long and slow, no problems.  They clearly had an endurance problem and an endurance challenge in the office showed an immediate failure in under 30 seconds (we will try to shoot a quick video so show our little assessment so be patient with us). The point here today is that if there is a joint limitation, there will be a limitation in skill, strength or endurance and very likely a combination of the 3. If you cannot get to a range, then any skill, endurance or strength beyond that limitation will be lost and require a compensation pattern to occur.  This patient’s arch cannot be restored via the methods we describe here on our blog and it cannot be restored by an orthotic. The orthotic will likely further change, likely in a negative manner, the already limited function of the 1st MPJ. In other words, if you raise the arch, you will shorten the plantar fascia and draw the 1st MET  head towards the heel (part of the function of the Windlass mechanism) and by doing this you will plantarflex the big toe … .  but weren’t we praying for an increase in dorsiflexion of the limitus big toe ? ……..yes, exactly !  So use your head  (and spank the orthotic when you see it used in this manner.  ”Bad orthotic, bad orthotic !”)

So think of all of this the next time you see a turf toe / hallux rigidus/ hallux limitus. Rattles your brain huh !?

This is not stuff for the feint of heart. You gotta know your biomechanics.

Shawn and Ivo … .the gait guys

Addendum for clarity:

a Facebook reader asked a question:

From your post: “if you raise the arch, you will shorten the plantar fascia and draw the 1st MET head towards the heel (part of the function of the Windlass mechanism) and by doing this you will plantarflex the big toe … . but weren’t we praying for an increase in dorsiflexion of the limitus big toe ? ” I always thought when the plantar fascia is shortened, it plantar flexes the 1st metatarsal (1st ray) and extends (dorsiflexes) the 1st MTP joint….

Our response:  

We should have been more clear, our apologies dear reader.  Here is what we should have said , ” The plantar fascia is non-contractile, so it does not shorten. We meant conceptually shorten. When in late stance phase, particularly at toe off when the heel has raised and forefoot loading is occurring, the Windlass mechanism around the 1st MET head (as the hallux is dorsiflexing) is drawing the foot into supination and thus the heel towards the forefoot (ie passive arch lift). This action is driving the 1st MET into plantarflexion in the NORMAL foot.  This will NORMALLy help with increasing hallux dorsiflexion. In this case above, there is a rigid 1st MTP  joint.  So this mechanism cannot occur at all. In this case the plantar fascia will over time retract to the only length it does experience. So, if an orthotic is used, it will press up into the fascia and also plantarflex the 1st MET, which will carry the rigid toe into plantar flexion with it, IN THIS CASE.”

Welcome to rewind Friday, Folks. We always seem to be talking about bunions, and receive quite a few questions on them. This brief video discusses where they come from.

Enjoy!