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Custom orthotics addiction

Discussion in 'Biomechanics, Sports and Foot orthoses' started by Buggs, Jul 16, 2006.

  1. Buggs

    Buggs Member


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    Do custom orthotics make feet/legs weak? Do they make you addicted?

    I got this idea that once i get used to my orthotics I will be less and less able to walk without them.... like even small walks without them will cause EVEN MORE damage when the feet/legs get used to them than before I started wearing them....
    I think what I m trying to say is that it is quite proportional - the more the feet get dependant on the orthoses the more hardere and "risky" will it be to walk without them...
    Right?

    When I used to trained heavy... I used to train legs barefoot.... And I always felt more natural, balanced and stronger when barefoot...
     
  2. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    no....
     
  3. Scorpio622

    Scorpio622 Active Member

    If anything, it is probably the opposite. Orthotics used to decrease pain and increase function can only enhance muscle performance as abberant firing patterns are avoided and the individual can train harder/longer.

    The addiction that I see is in some docs who prescribe FFOs for everything ($$$$).
     
  4. Atlas

    Atlas Well-Known Member


    Absolutely brilliant.


    Next time you have back pain or knee pain, and your physical therapist prescribes you strengthening exercises...and they fail; go back and read this quote from Scorpio, and then find another practitioner.

    Pain inhibits muscular activity. Full stop.
     
  5. However, orthoses have been shown to alter EMG activity and metabolic cost.

    Also, I thought the work of Janda demonstrated why we should focus on restoring muscle length as oppose to strength? Moving the length / tension curve "up", with strength training as oppose to "along" with length restoration. Thus, with restoration of length, tension is developed in the appropriate range position?
     
    Last edited: Jul 17, 2006
  6. Atlas

    Atlas Well-Known Member

    I think Janda looked at both for memory. I think he was suggesting that with dysfunction you may get a tight strong agonist and a weak long antagonist. Hence you lengthen/stretch the agonist group and strengthen the antagonist group.

    Long time since I was taught this, but this is how I recollect it.

    This makes a touch more sense than the 'strength/control' panacea that is dished out today since the work of Jull and Richardson.

    The issue will always be assess fully and accurately. Stretching is relevant only when the relevant tissue is short. Strengthening is relevant only when the relevant tissue is weak.


    The next case of unilateral plantar fasciitis that presents will direct us to the recipe book. Page 68 will tell us to give gastro/soleal stretching. But should we do this when our assessment suggests that gastrocs and soleus are longer on the symptomatic side???
     
  7. I believe that you are all missing the point.

    If by weak, you mean having less strength, then I have never seen it. If by weak, you mean fatigue, then I have seen it happen if the orthoses are improperly made, which I have done to patients a few times. If custom orthoses are properly made, then they should make the individual fatigue less with prolonged walking or running activities.

    One of the comments I make to many patients when they report that they can't walk without their orthoses without pain (that usually gets a smile or chuckle from the patient) is that they are now "orthotic junkies", constantly needing their "orthotic fix" throughout the day to be content. In this manner, then, yes, being able to walk all day without pain is "addictive" for many patients since they no longer need to worry about their chronic foot pain being a handicap to them. This is probably one of the greatest pleasures of being a podiatrist: being able to give to patients the wonderful benefit of having painfree feet so that they can resume their lives with a minimum of inconvenience.

    You may be able to walk less without foot orthoses since you are better able to now notice that you have pain or fatigue when you don't have the orthoses on. The central nervous system (CNS) has a built-in stimulus-modulation process that is called "adaptation" or "accommodation" where a constantly occurring stimulus is "tuned off" by the CNS http://www.unlv.edu/faculty/jyoung/Nervous System - Peripheral and Central.pdf. If the stimulus becomes infrequent, then adaptation or accommodation shuts off. If the stimulus is frequent or constant then it turns on to remove some of the perceived significance from the stimulus. This CNS adaptation or accommodation mechanism is what allows animals, such as humans, to forget about the "feel" of the clothes on our bodies and tune out extraneous noises so that we can concentrate on the task at hand during our daily activities. A constantly occurring pain stimulus feels less significant or severe to an individual than the exact same pain stimulus that occurs infrequently. Therefore, if the patient has progressed from constant pain without orthoses to only having infrequent pain when they don't wear their orthoses (once they have been accustomed to having no pain while wearing them), then the infrequent pain stimulus may be perceived to be greater when the patient walks without their orthoses (once they have been accustomed to having no pain while wearing them) than the exact same pain stimulus would have been perceived when they have that pain constantly before they have received their orthoses.

    When I used to run 75-90 miles a week competing as a long distance runner in high school and college, I trained in shoes and barefoot and felt lighter without shoes, felt faster without shoes, but didn't necessarily feel stronger. Shoes and orthoses allowed me to train harder, longer and more frequently that ultimately, I believe, made me a faster runner.

    I don't think it is "risky" to walk without orthoses. Getting older, fatter, exercising more strenuously, and going barefoot is much more "risky" than not wearing orthoses.
     
    Last edited: Jul 18, 2006
  8. Atlas

    Atlas Well-Known Member



    Good point.
     
  9. EdGlaser

    EdGlaser Active Member

    Good question Buggs

    Dear Buggs,
    This is a very common concern among PT's, ATc's and exercise physiologists. It is their experience and training that the use of a back brace for example replaces the function of the transversus abdominus muscle and thereby weakens it. When the brace is removed the weaker back and abdominal muscles make further back injury more likely. Some orthoses, like the UCBL and some very rigid graphite orthoses or those with excessive flanges may indeed may cause such limitation of motion as to have a similar effect. The saving grace of most of these very rigid orthotics, in this respect, is that they are usually so “cast corrected” that by the time the foot hits them at the very end of pronation, they only reduce tissue stresses. Orthoses that aim to reposition the foot are in greater danger of having this effect because they are far more limiting in ROM. This is one reason why it is crucial to get the flexibility correct whenever you are trying to change gait. You want to control pronation, not block it. Very rigid orthoses that raise the MLA will therefore have that effect.

    On the other hand, if flexibility of the orthoses is correct, orthoses that reposition the foot will have an added beneficial effect. Compare walking to other physical exercise. If you are lifting weights with very bad form, you may actually hurt yourself. If you use good form, the same exercise will build you up. That is why personal trainers and physical therapists and exercise physiologists stress good form when lifting. Walking with good form will do the same thing. It will build up muscles that are now working more efficiently. Some muscles that have hypertrophied in order to compensate for the poor position the over-pronated foot is trying to overcome… the inefficiency of walking with bad form. These muscles will return to normal tonus when the orthoses are removed.

    In essence, you are right, orthoses ARE and should be addictive. That is, if they are making a real change in the gait cycle, they should be worn as much as possible. It hurts to go back to a collapsed arch and inefficient gait. There is one saving grace however and that is the adaptation of the soft tissues may be helpful. What I saw in practice and what our clients report is that after wearing orthoses for a prolonged period of time (greater than a year), they can tolerate longer periods without them before symptoms reappear. We theorize that it takes a few hours or days for the tissues to stretch out to the end of the ROM again and for the resulting trauma to reach the threshold of pain. Could being without orthoses after wearing them for prolonged periods then lead to possible injury. That is speculative and needs more study. I would certainly think it is possible….a good reason to continue wearing your orthotics.

    Ed
    :)
     
  10. Atlas

    Atlas Well-Known Member

    I agree Ed, that most PT's etc will say this. What they don't understand is that not all back pain is due to muscle weakness. Back pain that is due to a compressed disc (prefers bed rest to prolonged standing/sitting), would benefit from a brace. My analogy is, if you break your arm, 6 weeks in plaster cast will weaken your musculature, but it is a necessary evil. The alternative is to 'keep it strong and moving', but non-union will develop. What is the priority? But you are right in that invariably all musculo-skeletal spinal/back therapists will suggest this.



    I would add that the pathological forces/motions would come into play again, once the successful orthoses are removed. The compounding effect may mean that it would take more time for small repetitive pathological forces to manifest.


    In other words, the compound effect of pathological forces.
    A lot of good info in your post.
     
  11. Buggs

    Buggs Member

    Thak you all for the answers you gave...


    But Im not talking about collapsed arch, or "inefficient" gait...
    Can gait be "efficient" and an overuse injury still occur?

    I dont mean abnormalities of inherited sort


    A person who has plantar fastiitis without any severe or mild anomaly needs a different amount of support and control than a person who has an obvious disorder and illness.

    I always thought that pronation is a "normal" thing in movement.
    It just gets old and overused(like everything does with time)
    Now what is the "right" next step sound dificult to answer.
    It seems there are a lot of posibilities and variations of combinations when it comes to this. Does this look like there is need for more study or am I wrong?
     
  12. EdGlaser

    EdGlaser Active Member

    True, and probably less in the foot.

    You are right, bracing has its place in the treatment of acute trauma. Addiction to orthoses is probably more chronic in nature. I believe that there is merit to the idea that core stability, like pilates, exercises can cause limb rotations beneficial to gait and the foot and I also think it is also important that the patient have enough ROM in the superstructure to accept the changes that an aggressive orthoses impose such as knee external rotation and changes in pelvic tilt and rotation. If you are really trying to impose positive changes on the gait cycle in many cases a PT consult and eval can be enlightening. Ultimately, functionally, we are all trying to move the existing gait cycle as close as possible to the ideal gait cycle which is individual for that patient. Functioning closer to ideal is addicting, in a good way.

    Good point!


    Thanks,
    Ed
     
  13. EdGlaser

    EdGlaser Active Member

    I think that here you deal with probabilities. There should be a greater likelihood that an in-efficient gait would, place unusual stresses at the end of its ROM of pronation than an efficient gait. Probability of overuse injuries should drop...not that it will always work that way.


    There is alway need for more study.

    Each person does need a different amount of support right to left. I do not think the amount of support that a person needs is dependant on the diagnosis. Ideally the force should be enough to supinate the foot (supination resistance) and make positional chanes throughout the gait cycle which will tend to bring the (lower, overpronated) graph of STJ pronation/supination during stance closer to the "ideal" graph. I think that is more a funcion of body weight, foot flexibility and momentum.

    Each person has two of their own graphs (except amputees) and and two ideal graphs that are accessable to them now (and of course the goals may be re-evaluated following stretching and exercises).

    You are right that pronation is a normal part of the gait cycle. preferrable to blocking it, is controlling it.

    :) Thanks,
    Ed
     
  14. efuller

    efuller MVP

    Some would consider the most efficient gait is a gait where there is resupination in the latter half of stance phase. If a foot had a medially deviated STJ axis it would have to work harder than a foot with an average axis to achieve a supinated position in the latter part of stance phase. The medially deviated STJ axis foot would have to work harder because ground reaction force creates a greater pronation moment at the STJ as compared to the average axis foot. (Assuming the center of pressure is in the same position for both feet.) If the medially deviated STJ axis foot was placed on a orthosis that worked by causing discomfort in the arch, which causes the posterior tibial muscle to work harder, you would see a more "efficient" gait, that would be more likely to have an overuse injury, because the posterior tibial muscle is working harder.

    I think that some orthoses work in this manner because of the following observations. 1) Postier tibial muscle soreness after initiating orthotic therapy. (This is "getting used to" the orthosis.) 2)Seeing increased resupination while wearing orthoses. Then watching the patient walk barefoot and seeing resupination for a number of steps and then reverting to the more pronated position during gait after a few more steps. 3)Orthoses with medial arches higher than the barefoot medial arch height with wear paterns on the top cover laterally. When you stand and supinate using your muscles the pressure is lateral. When an orthosis pushes you into a supinated position the force has to be medial to the STJ axis and hence the wear pattern would be more medial. (Medial heel skives, especially higher amounts, will sometimes show wear on the medial heel cup)

    So, even though the gait "looks" more efficient, this does not necessarily mean that there is less chance of overuse injury. To prevent/ or treat overuse injury you have to reduce the stress on the injured structure. Resupination of the STJ, from the use of the posterior tibial muscle, can be a good thing if the injured structure is the first met head. However, if the injured structure is the posterior tibial muscle this would be a bad thing.

    Cheers,

    Eric Fuller
     
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