Welcome to the Podiatry Arena forums

You are currently viewing our podiatry forum as a guest which gives you limited access to view all podiatry discussions and access our other features. By joining our free global community of Podiatrists and other interested foot health care professionals you will have access to post podiatry topics (answer and ask questions), communicate privately with other members, upload content, view attachments, receive a weekly email update of new discussions, access other special features. Registered users do not get displayed the advertisements in posted messages. Registration is fast, simple and absolutely free so please, join our global Podiatry community today!

  1. Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
    Dismiss Notice
Dismiss Notice
Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
Dismiss Notice
Have you liked us on Facebook to get our updates? Please do. Click here for our Facebook page.
Dismiss Notice
Do you get the weekly newsletter that Podiatry Arena sends out to update everybody? If not, click here to organise this.

Toe flexor strength measurement and falls prevention

Discussion in 'Biomechanics, Sports and Foot orthoses' started by scotfoot, Oct 20, 2016.

Tags:
  1. scotfoot

    scotfoot Well-Known Member


    Members do not see these Ads. Sign Up.
    With regard to measuring toe flexor strength I believe it is important to considered measuring toe strength with the toes in a dorsiflexed ,toe off like position . This is particular true if toe strength is to be looked at in the context of falls prevention .
    The following method ,which would use a pressure mat/force plate combination to measure generated forces ,may allow this type of measurement .
    Use of the system would require the direction of a suitably qualified examiner for accuracy and safety and it would not be attempted by an individual at home or injury may result .

    PRESSURE MAT / FORCE PLATE SYSTEM
    INTRINSIC MEASUREMENT (position 1)
    The method would simply involve the subject standing with one arm out stretched touching a wall and with the reference foot in an late stance position on the pressure mat /force plate so that the ankle is flexed but the toes dorsiflexed .The subject would then be asked to push forwards against the arm/wall by flexing the rear toes . This might give a more accurate idea of the strength of the intrinsics .
    The stance would also involve having the shoulder of the extended arm positioned behind the forward foot placement .
    For clarity , the front foot would be about 2 feet in front of the rear or reference foot .The method might give the most functionally accurate idea of intrinsic toe strength particularly as it relates to the establishment of a stable position after a balance perturbation such as a trip .

    EXTRINSIC MEASUREMENT (position 2)
    The extrinsic toe flexors are thought by some to function isometrically during gait so this is probably the best way to measure there capacity .
    Again all that is required is the mat/plate and a wall . The idea is to measure the force that can be applied THROUGH the toes and not applied BY the toes .

    The test subject stands with the test foot on the pressure mat but now with there back to a wall . The heel of the test foot would be about 6 inches from the base of the wall . The non test foot is moved fowards about a 40 cm and makes light contact with the ground to avoid loss of balance . With their lower back touching the wall the subject now leans forwards at the waist till the COG is just over the MTFI of the test foot (. The forward foot keeps this stable ) . The subject is asked to stay in a forward lean but drive through their test foot toes to push there lower back against the wall as hard as possible .
    The result would give a good Idea of the max force that could be exerted THROUGH the toes to avoid forward progression of the COG over them and hence of the combined intrinsic and extrinsic toe strength .

    RATIONAL BEHIND THE POSITIONS
    The rational of the positions is that in a trip situation position 2 represents the foot acting as a lever arm against which the muscles of the body can act to slow the forward progression of the COM and also allow the contralateral hip to slow in absolute terms but accelerate relative to the contact side allowing any necessary additional strides to be taken in time to avoid a fall .
    Once forward progression of COM has been stopped the COM will be either directly over the blocking or forward foot but will most likely be behind this foot . This means that the COM will begin to move backwards and inwards unless the posterior leg can stop this movement and achieve equilibrium . This is were the 1 position is relevant .

    MEASUREMENT DEVICE
    A pressure mat system would be placed on top of a force plate and secured to it via, for example ,a temporary glue . This would allow both vertical and horizontal force components to be measured and collated .
    With regard to the above it might also be reasonably assumed that if the two named measuring position are valid then these would also be valid isometric strengthening positions .
    Any thoughts ?
    Gerry

    DISCLAIMER -- As far as I am aware the measurement and strengthening positions mentioned in the text above are untested and it is important to note that I am not recommending their use but merely putting them up for discussion .
    The author accepts no liability for any injury resulting from using the positions mentioned in the above text.
    Unsupervised use of the said positions may result in injury .
     
  2. efuller

    efuller MVP

    The purpose of walking is to move the center of mass. Tripping occurs because the swing leg is prevented from getting out in front of the center of mass. The act of walking is vaulting over the stance leg, while putting the swing leg out in front of the center of mass so that the momentum of the body can vault over the swing leg as it becomes the next stance leg. Lack of clearance of the swing leg is the reason for tripping (e.g. weak ankle dorsiflexors) and not weak toe flexors during stance. In walking, the goal of the body is to move the center of mass forward, not prevent the movement of center of mass.
    Eric
     
  3. Craig Payne

    Craig Payne Moderator

    Articles:
    8
    I don't necessarily disagree and it does make intuitive sense, but it could be highly likely that the values between strength testing when dorsiflexed correlate highly with them when they are fully extended.
     
  4. efuller

    efuller MVP

    I agree that ankle position matters for flexor hallucis longus, but not so much for flexor digitorum longus. FHL goes much further behind the ankle joint axis and has a much larger lever arm, at the ankle joint, than FDL. The muscles have a finite amount of distance that they can shorten. Especially pennate muscles. You can see people that have very strong hallux ipj plantar flexion with the ankle dorsiflexed and can't plantar flex at all with the ankle plantar flexed. Some of the total tendon excrusion is used up by ankle joint motion because the tendon has to move with ankle joint motion.

    On the other hand FDL tendon is much closer to the ankle joint, so ankle joint position matters much less for FDL.

    Eric
     
  5. scotfoot

    scotfoot Well-Known Member

    Eric
    The thread is more about recovery from a trip than how a trip or balance perturbation occurs .
    Craig
    There may well be a close correlation for most but in individuals where this is not the case it may be a sign of reduced ability to regain a balanced position after a perturbation .

    Regards
    Gerry
     
  6. efuller

    efuller MVP

    Gerry, I was disagreeing with the premise in the rationale. When the trip occurs the center of mass has passed the point where using the toe flexors can save you from a trip. I'm talking about the physics of how toe flexors could possibly aid recovery.

    You wrote:

    The rational of the positions is that in a trip situation position 2 represents the foot acting as a lever arm against which the muscles of the body can act to slow the forward progression of the COM and also allow the contralateral hip to slow in absolute terms but accelerate relative to the contact side allowing any necessary additional strides to be taken in time to avoid a fall .
    Once forward progression of COM has been stopped the COM will be either directly over the blocking or forward foot but will most likely be behind this foot . This means that the COM will begin to move backwards and inwards unless the posterior leg can stop this movement and achieve equilibrium . This is were the 1 position is relevant .
    To stop, or slow, forward progression the center of pressure of ground reactive force has to be anterior to the center of mass. The ankle plantar flexors, more than the toe plantar flexors, can shift the center of mass anteiorly, but only by the length of the foot and toes. If the center of mass is already over the foot when the trip occurs, then it is too late for activation of the toe flexors to shift the center of pressure forward. A trip occurs when the swing leg encounters an obstacle that slows the swing leg enough that it can't be placed far enough ahead of the body for the normal forward momentum to allow the usual vaulting of the body over the soon to be stance foot. The trip usually occurs at the lowest point of swing and that is when the swing foot is even with the stance foot. When this happens the center of mass is over the stance foot.

    In fact, one the center of mass is anterior to the center of pressure, contraction of ankle and toe flexors would tend to accelerate the whole body forward rather than pull the body backward over the ankle. At this point the lever of the foot will propel the body forward.

    Eric
     
  7. scotfoot

    scotfoot Well-Known Member

    Hi Eric
    I know exactly what you mean and if the COM is past the standing foot when a trip occurs then it is the foot involved in the initial recovery step that the rational applies to and so on for any subsequent steps .
    The rational would apply to the standing foot if the swing leg is delayed by an obstruction such as a step or roadside kerb (curb) or in older individuals employing a shuffle type walk with very little leg swing where the trip occurs before the COM is past the standing foot .

    Regards
    Gerry
     
  8. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Reliability of doming and toe flexion testing to quantify foot muscle strength
    Sarah Trager Ridge et al
    Journal of Foot and Ankle Research201710:55
     
  9. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Toe flexor strength is associated with mobility in older adults with pronated and supinated feet but not with neutral feet
    Kusagawa Y, Kurihara T, Imai A, Maeo S, Sugiyama T, Kanehisa H, Isaka T
    Preprint from Research Square, 22 May 2020
     
  10. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Reliability and validity of an enhanced paper grip test; a simple clinical test for assessing lower limb strength
    Panagiotis E.Chatzistergos et al
    Gait & Posture 16 July 2020
     
  11. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    The effect of interventions anticipated to improve plantar intrinsic foot muscle strength on fall-related dynamic function in adults: a systematic review
    Lydia Willemse, Eveline J. M. Wouters, Henk M. Bronts, Martijn F. Pisters & Benedicte Vanwanseele
    Journal of Foot and Ankle Research volume 15, Article number: 3 (2022)
     
  12. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Increased toe flexor strength does not relate to altered postural sway during static upright standing after 12 weeks of multicomponent exercise training
    Keiji Koyama, Junichiro Yamauchi
    Eur J Sport Sci. 2022 Mar 8
     
  13. scotfoot

    scotfoot Well-Known Member

    I haven't seen the full text of this paper and don't know what they used to measure toe flexor strength or what exercises they used to strengthen the toe flexors . However, from their results I would guess they used the usual toe grip dynamometer, which involves pulling a bar with your toes, for measurement .
    As almost all now realise this does not measure intrinsic foot muscle strength (Ridge et al ) . For exercises they may well have used toe curls and short foot rather than doming and so did not target the intrinsics in any case . Could be wrong about all of the above but on past form I doubt it and am not about to waste £38 to be sure .
     
  14. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Associations between the size of individual plantar intrinsic and extrinsic foot muscles and toe flexor strength
    Yuki Kusagawa, Toshiyuki Kurihara, Sumiaki Maeo, Takashi Sugiyama, Hiroaki Kanehisa & Tadao Isaka
    Journal of Foot and Ankle Research volume 15, Article number: 22 (2022)
     
  15. scotfoot

    scotfoot Well-Known Member

    Let's say these researchers are correct and that the adductor hallucis oblique head is the major contributor to toe curling strength . Their results and the results of Bruening et al, also indicate that the abductor hallucis is not a major contributor to toe curling force.

    So toe curls might strengthen the adductor hallucis but not the abductor hallucis . Wouldn't that tend to encourage the development of hallux valgus ?

    I'm not at all convince by this paper but, IMO, it does seem to make toe curling look like a bad exercise for the foot.
     
  16. scotfoot

    scotfoot Well-Known Member

    "Conclusion

    The ADDH-OH is the primary contributor to TFS production among the plantar intrinsic and extrinsic foot muscles as the result of the stepwise multiple linear regression analysis."

    An alternative, and I believe more plausible explanation for the results obtained by Kusagawa et al, would simply be that barefoot exercise ( martial arts are very popular in Japan and, I believe, even part of the school curriculum up till middle school), makes the adductor hallucis stronger but also improves foot flexibility.

    The toe grabbing force measured by their device involves toe curling but also produces a more arched foot . It could easily be that the more flexible the foot the more force it can produce on the grab bar and that adductor hallucis size is purely coincidental in as much as it has almost no bearing on the amount of force the grab bar records.

    If you start of with a flawed model the stats can produce some weird and wonderful results.
     
  17. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Toe grip force of the dominant foot is associated with fall risk in community-dwelling older adults: a cross-sectional study
    Satoshi Matsuno, Atsushi Yoshimura, Takuya Yoshiike, Sachiyo Morita, Yusuke Fujii, Motoyasu Honma, Yuji Ozeki & Kenichi Kuriyama
    Journal of Foot and Ankle Research volume 15, Article number: 42 (2022)
     
  18. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Association between toe pressure strength in the standing position and postural control capability in healthy adults
    Taishiro Kamasaki et al
    Gait & Posture; 23 April 2023
     
  19. scotfoot

    scotfoot Well-Known Member

    At last, researchers from Japan seem to have accepted that the best way to measure toe flexor function is to measure the ability to press the toes down rather than have them curl and pull on a bar .

    The study shows that toe press ability is linked to postural stability in healthy adults . Wonder if any clinicians involved with helping golfers will take anything from this thread.
     
  20. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Foot Problems and Their Associations with Toe Grip Strength and Walking Speed in Community-Dwelling Older Individuals Using Day Services: A Cross-Sectional Study
    Kashiko Fujii et al
    Nurs Rep. 2023 Apr 13;13(2):697-720
     
  21. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Reliability of Foot Intrinsic Muscle Strength Testing and Correlation with
    Corresponding Muscle Morphology in Elderly Adults

    Lulu Yin et al
    21 June 2023
     
Loading...

Share This Page