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. Everything that you are ever going to want to know about running shoes: Running Shoes Boot Camp Online, for taking it to the next level? See here for more.
    Dismiss Notice
  2. Have you considered the Critical Thinking and Skeptical Boot Camp, for taking it to the next level? See here for more.
    Dismiss Notice
  3. 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.

For Orthotic Success of FHL

Discussion in 'Biomechanics, Sports and Foot orthoses' started by gabrincha, Apr 5, 2008.

  1. gabrincha

    gabrincha Welcome New Poster


    Members do not see these Ads. Sign Up.
    My name is Gabriele Montini. I am Italian and am a student of “Podologia” on my way to becoming a foot health professional. On the 22 of April I have the academic defense to present at the University of Pisa. The title of my graduation thesis is "Hallux limitus versus Hallux rigidus: Disease, differential diagnosis and conservative treatment"



    I have chosen this topic because again in 2008, for the Italian orthopedic doctor exists uniquely HR.




    I hope that you might provide me with some information regarding orthotic treatment in Functional Hallux Limitus, FHL.

    I understand well that at the base of the orthotic there must also be the control of the rarefoot control but my questions are as follows:



    When and why place a kinetic wedge rather than a first ray cut out or first metatarsal head cut out or morton's extencion?


    In the case of hallux limitus structural is it correct to prefer a Morton’s extension or is this correction only applicable for HR?

    I realize that my topic is very broad but I would be very enthused and grateful for a short reply


    thank you for all and sorry for my english
     
    Last edited: Apr 5, 2008
  2. Re: For Orthotic Success in FHL

    Gabriele:

    Thank you for sending me the private e-mail and posting this also on Podiatry Arena so that others can also read along. I have never been to Italy but am a great admirer of the many famous Italian scientific and artistic geniuses that have contributed to our knowledge and culture for over thousands of years. I believe you are one of the few Italian foot specialists that are active on Podiatry Arena. Welcome!

    To answer your questions, in general, for functional hallux limitus (FnHL), my treatment of choice in foot orthoses is to make a well fitting medial longitudinal arch orthosis (e.g. 4.0 - 5.0 mm polypropylene plate), balanced 2-4 degrees inverted, with a slight medial heel skive (e.g. 2 mm), 16 mm heel cup, rearfoot post and a 2-5 forefoot extension (i.e. reverse Morton's extension) of 3 mm korex (or other suitable material) to the sulcus. For your information, the definition of FnHL is a reduction of 1st metatarsophalangeal joint (MPJ) dorsiflexion in weightbearing that is not present during the non-weightbearing examination.

    I will also use a similar orthosis prescription as above for patients that have a painfree dorsiflexion range of motion and a structural hallux limitus, where the 1st MPJ has less than 45 degrees of dorsiflexion in non-weightbearing examination . The theory here is to reduce the ground reaction force (GRF) plantar to the first metatarsal head during late midstance with the reverse Morton's extension. The increase in subtalar joint (STJ) pronation moment caused by the reverse Morton's extension (i.e. forefoot valgus wedge effect) is counterbalanced by the medial heel skive and increased longitudinal arch height from the orthosis that acts to increase the subtalar joint (STJ) supination moment. This "counterbalancing of STJ moments" will allow the patient to have more normal hallux dorsiflexion gait, increased late midstance supination/decreased late midstance pronation, a longer propulsive period and will significantly increase gait stability. You don't need a "kinetic wedge" to achieve these mechanical effects.

    Generally, the amount of 1st MPJ range of motion (measured from the transverse plane of the plantar heel to plantar 1st metatarsal head and the bisection of the shaft of the proximal phalanx of the hallux) necessary for normal gait function is considered to be between 45-70 degrees. However, this range of motion varies, depending on which reference you choose to quote from. Personally, I feel that hallux dorsiflexion above 45 degrees will not likely produce any gait pathology or other symptoms/pathology.

    For patients with structural hallux limitus where there is also a painful dorsiflexion range of motion before 45 degrees of dorsiflexion is reached, I will use a 3 mm Morton's extension (from end of orthosis plate to hallux IPJ then tapered to distal end of hallux) instead of the reverse Morton's extension. The theory here is that in order to allow the patient with painful hallux dorsiflexion to function with less pain during propulsion, the Morton's extension will limit the range of 1st MPJ dorsiflexion during propulsion so that painless ambulation may occur. The Morton's extension increases the GRF plantar to the 1st MPJ that will increase the 1st ray dorsiflexion moments which, in turn, helps prevent the first ray from dorsiflexing sufficiently to allow increased 1st MPJ dorsiflexion during propulsion.

    Hope this answers your questions.
     
    Last edited: Apr 6, 2008
  3. admin

    admin Administrator Staff Member

  4. falconegian

    falconegian Active Member

    Dear Gabriele,
    I'm Gianluca Falcone, an Ortopaedic Doctor!!!
    FHL is really something that in our Country is poorly recognised! The problem oforthotics prescription in Italy is that during the years Orthoses are precribed just for business and not by a DOctor Biomechanic Assesment. We must wark for a change of direction !!
    What Kevin replied to you is absolutly great. Functional limitation in first MTJ dorsiflexion is at the base of many dysfunction in foot biomechanics. Obviously ST joint must be always address in cases like this and often posting rearfoot allowing supination can solve the problem together with reverse Morton Extension!


    Dr. Gianluca Falcone
    Rome - Italy
    falconegian@alice.it
     
  5. gabrincha

    gabrincha Welcome New Poster

    Dear Doctor Kirby:



    Thank-you very much for getting back to me so quickly. The information you provided in answering my questions was much appreciated and very helpful. I admire you for both your outstanding academic skills and your kindness.



    Sincerely,



    Gabriele Montini
     
  6. Gabriele:

    Happy to hear that I have been of some help for you.

    It looks as though your fellow countryman Dr. Falcone is also interested in the subject of hallux limitus. Possibly you two could spread the word about Podiatry Arena to your other Italian colleagues and start your own Italian section of Podiatry Arena. You may have noticed that the foot health specialists from Spain and other spanish speaking countries now have their own "Espanol Forum" on Podiatry Arena

    I know there must be many more Italian foot health specialists that may be interested in discussing foot and lower extremity biomechanics topics (and other subjects) on Podiatry Arena.

    By the way, your questions were excellent. Keep up the good work!

    Ciao
     
  7. fabio.alberzoni

    fabio.alberzoni Active Member

    Re: For Orthotic Success in FHL

    http://www.podiatry-arena.com/images/smilies/Good-Post.gif
    It's sounds really good!thanks Kevin!
    In the Hospital yesterday we visited a patient with painful FnHL.
    My problem is that this "light" lady( 100 kg x 1,60 cm) has a forefoot valgus of 4-5° degrees bilateral and a rearfoot varus of 2° and an muscolar equinus partially compensated....
    How I can post the forefoot in valgus and post the rearfoot?
    The ff post in valgus would increase GRF on I ray and if I post the rearfoot inverted she gonna have several ankle sprain...(she already got peroneal tendons subluxation)...


    please help! thank you
     
  8. fabio.alberzoni

    fabio.alberzoni Active Member

    I'm not agree with you...I never saw a foot with dysfunction caused by FHL..

    Please could you explain better this concept?

    thanks,fabio
     
  9. falconegian

    falconegian Active Member

    Hi,
    probably I was not clear with what I thought about FHL.
    You can read this post to Understand what I said:
    The importance of a functional increase in dorsiflexion stiffness at the MTP joints during gait

    My suggestion is that FHL is very common and correcting fhl you can solve many pathologies of the foot like Plantar Fasciatis for example. FHL not always is symptomatic but its precence must be known and treated.


    Gianluca
     
  10. fabio.alberzoni

    fabio.alberzoni Active Member

  11. Re: For Orthotic Success in FHL

    A reverse Morton's extension (2-5 forefoot extension) of 3 mm (1/8") korex or EVA works well when combined with a 2 degree inverted balancing position of the rearfoot on the orthosis in these cases. The reverse Morton's extension decreases the ground reaction force (GRF) plantar to the 1st metatarsal head to help the functional hallux limitus (FnHL) and increases the subtalar joint (STJ) pronation moment so that there should be decreased strain on the peroneal tendons. The slightly inverted balancing positon will add little STJ supination moment to the rearfoot and will counterbalance the STJ pronation moment from the reverse Morton's extension. A 2-3 mm heel lift can be used also for the equinus in the orthosis.

    Hope this helps.:drinks
     
  12. efuller

    efuller MVP

    Re: For Orthotic Success in FHL


    A forefoot valgus post won't necessarily increase force on the first ray (I ray?). Many feet with functional hallux limitus will have high loads on the medial forefoot and low loads on the lateral forefoot. In some of these feet, you can slide your fingers under the lateral forefoot when they are standing. In these feet the goal of the forefoot valgus wedge is to increase force on the lateral forefoot and reduce load on the medial forefoot. High loads on the medial forefoot is what causes functional hallux limitus.

    In feet with peroneal overuse (may not be the same as subluxation), there is often a laterally positioned STJ axis and the ground will cause a supination moment. For these people to keep their forefoot flat on the ground, they must constantly contract their peroneal muscles. The contraction of the peroneal muscles will create sufficient pronation moment to worsen the functional hallux limitus. In these feet, a forefoot valgus wedge will reduce the force needed in the peroneal tendons and help the functional hallux limitus.

    If you wanted to post both the forefoot and rearfoot in valgus, you could add a forefoot valgus intrinsic post and do a lateral heel skive. (What kind of post did you want on the rearfoot?)

    Eric
     
  13. fabio.alberzoni

    fabio.alberzoni Active Member

    Re: For Orthotic Success in FHL

    "!The contraction of the peroneal muscles will create sufficient pronation moment to worsen the functional hallux limitus."
    Eric,thank you for your advices but I can't understand the reason of the sentence above.

    If you could explain me better I'll be grateful.
    fabio
     
  14. fabio.alberzoni

    fabio.alberzoni Active Member

    Re: For Orthotic Success in FHL

    @kevin kirby: Thank you. I'm gonna try to do what you told me with the poor goods that the hospital give us...ciao
     
  15. fabio.alberzoni

    fabio.alberzoni Active Member

  16. efuller

    efuller MVP

    Re: For Orthotic Success in FHL

    Most of the time, when the hallux is dorsiflexed, the windlass mechanism will create a supination moment at the STJ. Whether or not the STJ supinates is dependent upon the total moment at the STJ. So, the windlass can be appllying a supination moment and the ground or the muscles can be applying a pronation moment. The bigger moment wins.
    The windlass Mechanism can work in reverse. As the STJ pronates there will tend to be a plantar flexion moment on the hallux at the 1st MPJ. To visualize this as the STJ pronates the talar head moves anteriorly, lengthening and lower the longitudenal arch. As the distance from the calcaneal attachment of the fascia to the 1st proximal phalanx attachement of the fascia increases, the tension in the fascia will increase. Tension in the plantar fascia combined with compression forces at the MPJ create a plantar flexion moment acting on the proximal phalanx. This plantar flexion moment is what limits the motion of the hallux in functional hallux limitus.

    Hope this helps.

    Eric
     
Loading...

Share This Page