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Intrinsic foot muscle strengthening and hammer toe syndrome

Discussion in 'Biomechanics, Sports and Foot orthoses' started by smyliery, May 9, 2012.

  1. smyliery

    smyliery New Member


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    I am a chiropody/podiatry student in Canada and I have been looking into the idea of strengthening the intrinsic muscles and how that can slow the progression of, or even correct, cases of flexible hammer toe syndrome. I am looking into this with the idea that barefoot squatting, using one's own body weight or weighted squats, can enable this.

    I figure that doing this action barefoot causes the intrinsic muscles of the foot to contract in order to allow proper postural balance and foot stability. There is very little literature out there on the specific action of squatting and the intrinsic muscles, and I am curious to see if anyone has ever employed a similar technique in their practice and if they have seen any results from this.

    Any input or guidance would be appreciated.
    Thank you.
     
  2. efuller

    efuller Well-Known Member

    Why do you think squatting would change the intrinsic muscle activation? Why would intrinsic muscle activation be different barefoot vs. shod when squatting?

    I did look at cadaver feet with and without hammertoes. It did appear that the interosseus muscles actually did loose their ability to plantarflex the MPJ in the feet that had hammer toes. Creating a plantarflexion moment at the MPJ is relevant to the creation of hammertoe.

    Eric
     
  3. smyliery

    smyliery New Member

    Eric,

    Our thought is that when in shoes while squatting, the shoes are basically creating a stability platform for the feet where the muscles in the foot do not have to fire in the same way as they would when someone is barefoot. In squatting barefoot, the thought is that the feet have more of a role in mainating balance and stability.
    A general hypothesis that we have is that by strengthening the intrinsics, and in one specific case, the interossei & lumbricals, that they will be able to recover their function in helping to counter the overpowering forces of the extrinsic muscles that are/or may be exacerbating the flexible hammer toe syndrome.

    Ryan
     
  4. efuller

    efuller Well-Known Member

    The task of balancing requires that you shift the location of center of pressure under the foot relative to the location of the center of mass. The center of pressure is shifted by the contraction of muscles. This happens both shod and unshod. It may be true that ankle plantarflexors can shift the center of pressure further anteriorly when in shoes, but this may not necessarily be the case. When people balance they usually keep the center of pressure towards the middle of the foot and wouldn't need to put the center of pressure anterior to the met heads. Of course the above assumes that you are keeping the heel on the ground when you squat.

    If the heel comes off of the ground when you are squatting, you will have to plantar flex the toes to change the location of the center of pressure whether or not you are shod.





    Another issue is that at a certain point the dorsiflexion of the toes will put the line of pull of the tendon dorsal to the joint axis and that is what makes the interossei loose their effectiveness in plantar flexing the proximal phalanges. It won't matter how strong they are, they will have no leverage to cause plantar flexion.

    Eric
     
  5. CamWhite

    CamWhite Well-Known Member

    I have a little theory about this. I believe there is a direct correlation between hammer toe syndrome and functional hallux limitus. If the 1st MPJ "locks" during the propulsive phase of the gait cycle, the foot will roll laterally as you toe-off. Lesser toes need to act like outriggers and will "hammer" in an attempt to stabilize the foot. If they didn't hammer, there's a good chance we would lose balance.

    When we had a shoe store, nearly 100 percent of our customers with hammer toes also displayed all of the symptoms of having functional hallux limitus. While there are several ways of addressing Fnhl, we fitted the Cluffy Wedge in their shoes and sandals to see if we could register any improvement in their comfort. In almost every case, we noticed a visible reduction in hammering of the lesser toes. You could actually see them relaxing. There's a lot more I can talk about on this subject, but I learned early on that if hammer toes were present, there was a strong likelihood of Fnhl also being present.

    As a disclaimer, I have no financial interest in the Cluffy Wedge, and am also aware that there are other shoe/orthosis modifications to address this condition.
     
  6. Kevin Kirby

    Kevin Kirby Well-Known Member

    Could you please start using the idea to have people use barefoot squatting with or without added weights here in the Sacramento, California area? The number of patients with plantar plate tears and metatarsalgia will likely double which would make my practice even busier....could be a great practice management technique. Better yet, combine barefoot squatting with added weights along with barefoot running or running in Vibram FiveFingers....I could likely retire within a year or two with that practice management technique....:wacko::hammer::craig:
     
  7. Bodhidogma

    Bodhidogma New Member

    Kevin, congrats on treating a new member of the forum as though he is a moron. How dare he ask such a question?!? I suspect you often sit and contemplate just how astounding your intellectual prowess truly is.

    Please note the op mentioned that he is a student, and as such has not had the luxury of seeing thousands of feet like yourself. I am a student as well, and we simply posed the original question because there is not a lot of literature on the topic. Please don't mention barefoot running - that's not what we are talking about. We are talking about squatting, a movement much different than that of a running gait.

    If you have nothing constructive to add, or knowledge to share, don't bother posting.

    Thanks
     
  8. Bodhidogma

    Bodhidogma New Member

    Eric,

    Thanks for your reply. We are wondering if there may be a correlation between tactile sensation in shod and unshod feet and the firing of the intrinsic muscles of the foot? If you have ever squat barefoot vs shod you'll notice a different feel in how your feet stabilize themselves to the floor.
     
  9. Kevin Kirby

    Kevin Kirby Well-Known Member

    Yeah, it was probably uncalled for. I suppose just getting a little tired of the idea from the barefoot running advocates that "foot weakness" is the cause of all pathologies....
     
  10. Kevin Kirby

    Kevin Kirby Well-Known Member

    Ryan:

    Sorry for my rude comment. I apologize.

    Squatting would probably not increase intrinsic muscle strength. Squatting under load would likely cause significant risk of developing plantar plate tears and metatarsalgia. The best way to strengthen plantar intrinsic muscles is to either do flexion exercises of the digits (i.e. have patient sitting in a chair, put a hand towel under their toes and then have them "scrunch the towel backwards" with the digital flexors) or to have electrical stimulation done on a regular basis to these small muscles. Unfortunately, there is very little literature on this subject. I wouldn't expect plantar intrinsic muscle strengthening to help in any way with the resolution of hammertoe deformities. But, in my experience, plantar intrinsic strengthening may be helpful for cases of plantar fasciitis.

    Hope this helps.:drinks
     
  11. smyliery

    smyliery New Member

    Wow, it appears I've missed quite a bit since my last post.

    Eric - We appreciate the input. We didn't realize exactly how much comes into play with this topic.

    Cam - That is an interesting theory, and I'm interested in learning more. Have you done any work regarding that correlation? Or have you come across any articles relating to the topic?

    Bodhidogma - Thank you. Your friendship is irreplaceable.

    Kevin - I would like to think that someone who is considered fairly prominent in the field, and who is a college professor, would have a greater tolerance for students who wish to explore the profession in hopes of advancing the current knowledge base. I'm hoping it was just a case of having a late lunch.
    I understand that foot weakness is not the cause of all pathologies, but thought that with a flexible deformity some kind of muscle imbalance would be involved which may possibly be alleviated with muscle strengthening. I appreciate your input regarding the strengthening of the plantar intrinsics and their role in correcting a flexible hammer toe syndrome. In the case of a flexor stabilization, would some kind of strengthening of the interossei be able to overcome the earlier and longer contraction of the flexors? Maybe not to completely correct the flexible deformity, but perhaps to prolong the onset of the hammer toe syndrome?

    Ryan
     
  12. Kevin Kirby

    Kevin Kirby Well-Known Member

    Ryan:

    Unfortunately, I don't think that it is weakness of the plantar intrinsic muscles that causes these flexible hammertoes but rather an imbalance of flexion and extension moments that are controlled by the passive length-tension relationship of the plantar fascia, joint angles, extrinsic digital muscles and are greatly influenced by tight shoes.

    It would be a good research study, but my guess is that you would be wasting your time and your patient's time by having them do plantar intrinsic muscle strengthening exercises to cure flexible hammertoes unless you were certain that shoes were all proper length and that the balance from the stronger forces within the foot (i.e. extrinsic digital flexors and extensors and plantar fascia) were normalized.

    Hope this helps.:drinks
     
  13. efuller

    efuller Well-Known Member


    There might be a correlation, but I don't really like the explanation. Any explanation that has to do with foot and has the work "locks" in it is suspect. There are no keyholes in the foot. Also, in dynamic gait people with peg legs don't lose balance.

    On the other hand an explanation that I like better: People with functional hallux limitus may be contracting their flexor hallucis longis more to prevent hyper extension of the IPJ. There is a slip from fhl, the muscle, to fdl called the master knot of Henry. If you just sit their and attempt to plantar flex your 1st IPJ you will see your lesser toes plantarflex. I'm not sure that everyone has a master knot, but at least some do. Pull on the long flexor tendons, when the foot is weightbearing will tend to cause the hammertoe deformity. Don Green had a paper on this in JAPMA in the late 70's or early 80's. The master knot is what I think causes of hammertoes when you see the hammertoe in only the 2nd toe.

    Stand and grip with your toes to see what happens. It's hard not to use the plantar intrinisics as well.

    The FDL muscle is second best supinator to posterior tibial muscle (Hicks the function of the muscles) If the long flexor is gripping any treatment that increased supination moment from the ground could lessen the need for contraction of the FDL muscle. Of course with contraction of FDL you'd see hammering of all the lesser toes.

    Eric
     
  14. efuller

    efuller Well-Known Member

    I have squatted both shod and unshod and I don't see a difference. I'm able to keep my heel on the ground in both situations. I'm not saying that some people won't behave differently, just that I don't. And we are talking about behavior here. This is not purely a mechanical effect. What difference do you see?

    Eric
     
  15. Kevin Kirby

    Kevin Kirby Well-Known Member

    Bodhidogma:

    By the way Bodhidogma....I am very impressed that you called out the "Most Valuable Poster" in only your second posting to Podiatry Arena. Good on you for sticking up for one of your fellow students. What you did shows great character and courage and deserves one of these......:drinks
     
  16. CamWhite

    CamWhite Well-Known Member

    I have been doing some research online about hammertoes and functional hallux limitus. For that matter, I find very little information dedicated to functional hallux limitus on a Google search. Tons of information on structural hallux limitus is available. Here is one article, written by James Clough, DPM that was published in Lower Extremity Review: http://www.lowerextremityreview.com/article/functional-hallux-limitus-diagnosis-and-treatment

    Years ago, I attended a pedorthic footwear conference, and sat in on a session on functional hallux limitus. The speaker was James Clough. We had about 20 people in the class and he described the difference between structural hallux limitus and functional hallux limitus. He then demonstrated a simple foot assessment technique to check for "jamming" of the 1st MPJ. 18 out of 20 in the room had 1st MPJs that "jammed" bilaterally. He then demonstrated that pre-loading the hallux slightly into dorsiflection "unjammmed" all of our feet.

    As a shoe fitter, I was amazed at how counter-intuitive the Cluffy Wedge was, yet how effective it was for a wide variety of ailments. Here are some of the things I learned in our store after that conference:

    * FnHl is far more common than I ever expected. Over 90% of our adult customers complaining of foot pain, had a locking 1st MPJ
    * Nearly 100% of these customers had calusses under met heads 2-5 and pinch calluses on the medial side of the hallux. No callusing on the 1st met head.
    * The same customers had excessive wear on the lateral forefoot uppers of their shoes.
    * Most of these customers had some degree of "hammering" in their lesser toes/
    * They all walked with an out-toed gait.
    * Some of these customers complained of problems with anterior shin splints, IT band pain and lateral hip pain as well as low back pain.

    When I installed the Cluffy Wedge in their shoes, the overwhelming majority of the people that tried them expressed immediate lessening of foot, leg and back pain. People with hammertoes had a visible reduction in hammering, in most cases. I have since talked with Dr. Clough several times and shared my observations with him. He essentially confirmed that allowing the Hallux to function freely without "jamming" returns the foot to a stable platform, thus decreasing the load on the lesser metatarsals. For this reason, we also found the Cluffy Wedge to be very effective for many suffering from Morton's Neuroma pain.

    I am very aware that there are other ways to deal with FnHl, including 1st Ray cutouts and reverse Morton's extensions, but we stuck with the Cluffy Wedge because it worked very effectively for many of our customers.

    As a disclaimer, it's important for me to note that I have no financial interest in this post. I do not rep the Cluffy Wedge, nor do I have a retail store any more. I am simply sharing what I observed on the floor for several years. All told, we fit about 1,600 people with this device and had about a 1/2 a percent return rate.
     
  17. Stanley

    Stanley Well-Known Member

    I have seen some weightlifters whose toes have improved with shod weightlifting, though but not enough to know for sure.
    Competitive power lifters use shoes to squat but use very thin slippers to dead lift.(http://www.liftinglarge.com/Deadlift-Slippers_p_35.html) A friend of mine set a world's record in the dead lift using slippers. The reason for the difference has to do with the advantages for the lifts.
    In the squat to squat further down requires more knee and ankle dorsiflexion. If the ankle does dorsiflex enough, then the body is moved posteriorly which requires compensation or the body would fall over backwards. The normal compensation for this is loss of the lumbar lordosis which places the discs in a vulnerable position. A heel lift helps prevent this.
    In the dead lift, the weakest part of the lift is, more often than not, at the beginning of the lift. By lowering the body, the weak part of the lift is reduced. Try deadlifting off blocks sometimes (which is used as an assistance exercise for the deadlift), and you will see this for yourself. This slippers do not raise the body as much as shoes do, and this relatively lowers the body.
    I would like to see the results of your study. May I suggest that you have some EMG data with your work, and maybe try deadlifting in your study.

    Regards,
    Stanley
     
  18. musmed

    musmed Well-Known Member

    Dear Stanley
    Hi,
    the great Russian weightlifter V. Vasalov in the 60's used a school shoe to perform his squat and clean and jerk
    In those days there was the straight power lift and for this he used a flat heeled shoe.
    In the 60's everone copied him. I never saw an adductor problem let alone heard of one, simply because when you use a heel say 1/2 inch it is impossible for you to abduct your knees when lifting. Using a flat shoe, the only way is to abduct and thus the tears.
    I instruct all my athletes to use a heel lift- old school shoe is cheap and best

    With hammer toes that can be straightened easily with your fingers is a simple sign the lateral cunieform bone is stuck.
    Mobilise the cunieform and bingo no more hammer toes. so simple
    Like Kevin says it is due to a problem between the extensors and flexors and in all cases of stuck lateral cunieform bone the EBD is short and tense.
    Have a look a surpriseyourselves.
    Regards from the sunny south coast
    Regards
    Paul Conneely
     
  19. wdd

    wdd Well-Known Member

    Given sufficient room in shoes, etc, is increasing intrinsic muscle strength all that is required to functionally straighten the toes?

    It always seems to me that the intrinisc are, even at the best of times, such small muscles in comparison to the long flexors and extensors that to straighten the toes they have do do it before the long extensors and flexors fire. If the extensors and flexors fire before the intrinsics, no matter how exercised the intrinsics are, they are on to a hiding to nothing.

    Is it simply a matter of strengthening muscles or is there likely to be a neurological component (altered phasic activity) , no matter how subtle, sub-clinical?

    Bill
     
  20. Stanley

    Stanley Well-Known Member

    Hi Paul,

    So good to hear from you. I should have made myself more clear. The proportional length of the femur and ankle dorsiflexion are the two factors that determine whether a heel lift is required in squatting. With a proportionally longer femur, at 90 degrees the center of mass is displaced posteriorly further than with a proportionally short femur. Limitation of ankle dorsiflexion prevents the tibia from anteriorly displacing the center of mass, so other compensations are required. Hip flexion is a normal component of the squat. Additional flexion of the hip may or may not be available. That leaves flexion of the spine. Thoracic flexion is probably the poorest choice, as it causes the ribs to sublux. A lifter can get away with lumbar flexion, but not forever. An old school shoe provides a heel lift and is relatively stiff and if comfortable makes a great squatting shoe.
    If a heel of a shoe is too high (sometimes in the snatch lifters will raise the heel high additionally and will use this for other lifts), the knee has additional flexion which increases tension in the patellar tendon. I am not clear about the adductors that you are relating to heel height. An equinus can be associated with external rotation of the foot and leg and put the knee in a valgus position. Is this what you are referring to?

    Thanks Paul. I correct a calcaneus for the flexor digitorum brevis (in plantar fasciitis) using the same principle. I do this by massaging the posterior talocalcaneal ligament. Then I will do reverse strain counter strain of the flexor digitorum brevis.
    I will look for the lateral cuneiform.

    Regards,
    Stanley
     
  21. Stanley

    Stanley Well-Known Member

    Excellent question!!

    A further question is: are the muscles inhibited and why?

    Regards,

    Stanley
     
  22. musmed

    musmed Well-Known Member

    Dear All
    An important fact lies in the embryology, as does everything.

    The dorsal limb bud develops into amongst other muscles the
    short head of the biceps
    peroneals
    dorsal foot muscles

    all the rest are from the ventral limb bud

    "so what"' I hear...
    any disruption to any of the above will and can lead to inhibition of the others. They all must be looked at for a prolonged successful outcome.

    My definition of inhibition is: the muscle is not weak it is being made to act weakly.
    These muscles are all developed via the motor cortex
    They are different from the postural muscles. They are cerebellum muscles pathway ie. posture

    everyone treats them as the same. Nothing further from the truth.

    You must stretch them to length before you strengthen them. The only thing you will do is increase the inhibition and make matters worse.

    Stanley, I will try out your technique at my weekend Workshop in Adelaide.
    Regards to all

    Lovely sunny day in Sydney, cool nights= winters coming

    Paul Conneely
    www.musmed.com.au
     
  23. Dananberg

    Dananberg Well-Known Member

    Eric,

    Folks with peg legs don't have anything restricting the sagittal pivot, so can easily move over the peg. Therefore, the correlation as you describe is not relevant to this discussion.

    Sites on the foot can become resistant to specific motions for a wide variety of reasons. As Cam alluded (and described more fully in later posts), hammertoes do relax and reduce when the FnHL is adequately treated. Toes grip for balance. Repetitive use over millions of steps creates the chronic contraction. Over time, as muscles respond to dysfunction, they can often become inhibited by the body, resulting in further imbalance and dysfunction.....a rather nasty cycle.

    Howard
     
  24. CamWhite

    CamWhite Well-Known Member

    Howard,

    Thanks for your response. I am not a podiatrist, just a shoe fitter. But I couldn't help but think that if FnHl causes a saggital plane obstruction during the propulsive phase of the gait cycle, then the resulting frontal/transverse compensation has to trigger a hammering response to maintain balance. Over 8,000 steps a day, repetitive compensatory hammering could lead to dysfunction.

    Interestingly, once my wife's FnHl was identified and addressed, her flexible hammertoes completely straightened out within 2 weeks.
     
  25. Simon Spooner

    Simon Spooner Well-Known Member

    I guess it depends on what you mean by a "peg leg" and where you deem the sagittal plane pivot to be necessary. Here's an image of an artificial leg from 1913 made from wood and bakelite. Note that the leg has no ankle nor foot joints. Was the owner of this prosthesis able to walk in it?- probably, despite the fact that there is no sagittal plane pivots within the foot or ankle. "Yes but the bottom of the foot section resembles a shoe and as such has a "toe-spring"". So do shoes...
     

    Attached Files:

  26. Simon Spooner

    Simon Spooner Well-Known Member

    I agree here, in part. However, I prefer to think in terms of muscular length/tension relationships in relation to joint positions.

    Here's a coupe of images from a lecture I used to give a decade or so ago. Shortened muscles will tend to be recruited more easily according to Janda and as we can see from the left hand image, they develop their peak tension in the joints inner range; lengthened muscles will tend to generate their peak tension at the outer range of the joint and will test weak in inner range. The aim of treatment should be to bring the length/ tension relationship toward the line labelled as "control".

    If one attempts to strengthen the muscles, all that happens is that the length/tension curves rise vertically (as can be seen in the right hand image). In order to move the curves horizontally, so that the muscles hit their peak tension around the mid-range of the joint, you must focus on and change muscle length otherwise the shortened will still hit it's peak tension too soon within the joint range, and the long muscles will still be weak in inner range and overly strong in outer range.

    It's all Janda based stuff. One of my problems with his work and one of the reasons I stopped teaching this stuff so much is that he assumes that human muscles are similar to their animal counterparts in that the muscle fibre population was heavily biased and different in muscles with a mobilizing role and muscles with a stabilizing role: he suggested that the stabilizers contained predominantly slow twitch/ tonic fibres and that the mobilizers contained predominantly fast twitch/ phasic fibres. While they exhibit heavily biased differences in other animals. They don't so much in humans. Humans generally have a reasonably equal share of both fibre types within the majority of their muscles- I'll see if I can find the papers that looked at this, but I was researching this 15 years ago, so no promises, and maybe things have changed (I recall soleus was heavily biased and maybe tib ant.). I guess Paul's neural pathways might help. But, if we're talking about muscle imbalance between the long digital flexors and extensors... I guess fibre type population can change with use / disuse.
     

    Attached Files:

  27. Stanley

    Stanley Well-Known Member

    Hi Paul,

    Would this also include the ligaments and joints controlled by those muscles?

    Regards,
    Stanley
     
  28. musmed

    musmed Well-Known Member

    Dear Dr. Spooner

    I tend to agree with you in this regard. I treat the muscles according to which cell clump they came from in the first instance. So my lateral leg= short head biceps, peroneals and then dorsal foot muscles.
    Next I attack the rest.
    You will be surprised how well this simple trick works.

    There is alot in those diagrams and what you said in Jones' strain counterstrain.
    Just proves nothings new.
    Regards
    from a wet Adelaide
    Paul Conneely
    www.musmed.com.au
     
  29. musmed

    musmed Well-Known Member

    Dear Stanley
    The answer is yes simply because all these tissues came from the same cell.
    Keep well
    wet in Adelaide off to do a dry needling workshop
    Regards

    Paul Conneely
    www.musmed.com.au
     
  30. james clough DPM

    james clough DPM Active Member

    One of the things not mentioned but relevant to hammertoe deformity is the plantar fascial attachments into the proximal phalanx and the role they play in stabilization of the digit. When the windlass is not working well, driven bu FnHL, the other slips into the toes are also not stable.
    If the MTPJ's are edematous from chronic overload how can the interossei stabilize the toe, pulling into a swollen joint? Loss of intrinsic stability from these 2 events leads to overpowering of the extrinsics and ultimately, deformity. I do not know if the issue is strength as much as these other issues.
     
  31. Stanley

    Stanley Well-Known Member

    Hi James,

    Marvin Steinberg wrote about this years ago and proposed interspace injections with corticosteroids and local anesthetics. I think he talked about the extensors firing to decrease the load on the metatarsals.

    Regards,

    Stanley
     
  32. Simon Spooner

    Simon Spooner Well-Known Member

    Here's a nice easy little study. Measure hallux dorsiflexion stiffness, then measure the dorsiflexion stiffness of each of the lesser toes, one at a time. Then dorsiflex the hallux by some degrees and re-measure the lesser digits dorsiflexion stiffness, one by one. Then dorsiflex say the third toe and re-measure the the hallux dorsiflexion stiffness.

    Might do this one when I get back to work on Monday.

    Here's one of my hypotheses: if we dorsiflex the hallux and see arch raising as a response, the dorsiflexion stiffness will be lower in the lesser digits when the hallux is dorsiflexed than when it is not.

    For the record, I'm not a big fan of statements like "the windlass is not working well", but that's another story.
     
  33. james clough DPM

    james clough DPM Active Member

    Nice idea. How will you measure stiffness? My hypothesis would be the opposite, that as you engage the windlass through dorsiflexion of the hallux , the slips going into the toes will also tension, providng more stability to the MTPJ in dorsiflexion.
     
  34. james clough DPM

    james clough DPM Active Member

    Marvin Steinberg wrote about this years ago and proposed interspace injections with corticosteroids and local anesthetics. I think he talked about the extensors firing to decrease the load on the metatarsals.

    Why inject when you could possibly cause deleterious side effects? I have seen too many side effects from this and would not inject this area ever. Way too risky. By allowing plantarflexion of the first metatarsal you will transfer the weight off the lesser metatarsals and pressures will be reduced on the lesser MTPJ's, resulting in reduction of edema and normal functional balance.
     
  35. Simon Spooner

    Simon Spooner Well-Known Member

    I got a jig that I built to do this, its got a force gauge and a piston that pushes up under the digits enabling the measurement of load/ displacement. I got another one which use a force gauge and a sling which pulls the toes up- I'll see which one works the best for this.

    Here's my rationale James: if we dorsifex the hallux and observe arch raising, then plantar fascia has been "wound" around the first metatarsal head, yet not around the lesser metatarsal heads. So while the tension in the slip to the hallux should be increased, the tension in the slips to the lesser toes should be decreased. A lower arch should = more plantar fascial tension; a higher arch should = less plantar fascial tension. Since the lesser digits haven't changed position, yet the arch has raised, the tension in the slips to the lesser digits should be reduced when the arch is raised by the windlass effect at the hallux. This should reduce the reverse windlass force in the lesser toes and should thus reduce their dorsiflexion stiffness. Depends what happens to the centre of pressure and flexor muscles activity when you dorsiflex the hallux though. Hope that makes sense. I suspect the effect will decrease as we move from medial to lateral. There's more to it than that, STJ axial position will come into play too, but that's the gist of it.

    BTW, during weightbearing all the slips have tension whether the toes are dorsifexed or not. Hicks described this as the reverse windlass mechanism.
     
  36. james clough DPM

    james clough DPM Active Member

    i understtand you logic. I will be curious on your findings.
     
  37. Stanley

    Stanley Well-Known Member

    Hi James,

    I was just relaying an article that was written. Steinberg used a very low concentration of steroids when he did this, so maybe that is why he didn't get the complications that you are concerned about. For the record, I allow the first met to drop in my orthoses so that the windlass effect is allowed to occur, and it works better than when I used to just take pressure of the affected metatarsal.

    I was also thinking that one of the reasons it may have worked was that some of those points may have corresponded to acupuncture points.

    Regards,
    Stanley
     
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