Clinical Biomechanics Boot Camps

Taking it to the next level!

Global Podiatry and lower limb related courses and seminars

The Clinical Importance of Navicular Drop and Navicular Drift

I am a big fan of teaching people how to measure the navicular drift and drop. However, the evidence is that for clinical use they are not that reliable, so that does limit the usefulness of these clinical tests in clinical practice.

Having said that, I still think we should be teaching how to do it, but in the context of the unreliability of them. The reason for this is that the concept behind navicular drift and drop does have implications for foot orthotic prescribing. What learning how to do the tests gives clinicians is an appreciation of the relative movements of the midfoot in the sagittal and transverse planes. Navicular drop measures the sagittal plane motion of the midfoot and navicular drift measures the transverse plane motion of the midfoot. Learning how to do the measurement of these two gives an appreciation of the relative motion of that midfoot in the sagittal and transverse plane. Once that appreciation and understanding is grasped, then there is probably no need to do the measurements on a routine basis in clinical practice. You can just observe it and note how much drop there is compared to how much drift there is. Are the about the same or is there more of one compared to the other?

My impression is that the amount of navicular drift should be about the same as navicular drop. If drop is greater, then that means that there is more movement in the sagittal place compared to the transverse plane. This means there is more arch collapse, when means that the foot orthotics need to have more support in the midfoot. If the drift is greater, then that means there is more movement in the transverse plane compared to the sagittal plane. This means that there is more movement of the midfoot medially rather than arch collapse. This means that foot orthotics need more medial and lateral support to control that midfoot transverse plane motion.

The Lunge Test Should be Done in Footwear

I think we all know that the range of motion of the ankle joint is important for normal function. I have made no secret of how useful I think the lunge test is in evaluating that ankle joint range of motion. While there is some discussion as to what is the normal value for the lunge test (I think its around 35-38 degrees) or even if the ankle joint range of motion must be done in subtalar joint neutral (I don’t think it doesn’t need to be), the lunge test is still proving useful and being widely used in clinical practice.

In the early days of running the Clinical Biomechanics Boot Camps we used to do a lot of practicals on the lunge test. Participants would practice on each other and I would go around the room to check how they were going. It was surprising just how many would be considered tight on the lunge test. I would then use my hand as a “heel raise” and get then to stand on that. Almost always they then had a normal range of motion using the lunge test. I soon come to realise that the “heel raise” of my hand was doing what the shoe did, in that all shoes typically have a higher stack height in the heel than the forefoot (the drop). People function and walk in shoes, so the lunge test (and probably as many clinical tests as possible) should be done in the shoes. When we started doing the lunge test barefoot and then in the shoes at the Clinical Biomechanics Boot Camps, almost everyone who was under what was considered normal, was within normal limits when the test was repeated in their footwear. This has implications of the nature of the intervention and if the calf muscles were really limited or not.

There is a whole lesson in the online version of the Clinical Biomechanics Boot Camp devoted to this.

Please consider doing the lunge test in the patients shoes.

Fluoroquinolone induced tendinopathy

Fluoroquinolones are antibiotics that are commonly used to treat a variety of illnesses such as respiratory and urinary tract infections, with ciprofloxacin and delafloxacin being the most common. However, there is the issue that fluoroquinolones increase the risk for tendinopathy. This means it is important that the drug history of anyone with a tendon issue is evaluated.

Fortunately this risk only appears to be associated with the first and second generation fluoroquinolones with the third and fourth generation drugs not being associated with an increased risk of tendinopathy.

The Entity that is “Functional Hallux Limitus”

Functional hallux limitus is a theoretical construct. There is no doubt that the phenomenon that is functional hallux limitus exists, but that can often be as far any any agreement or consensus gets with this. There is no doubt that there are some feet when the foot is up in the air that there is a full range of motion available at the the first metatarsophalangeal joint yet when that foot is weightbearing during gait, that joint just does not want to move. That is the definition of what functional hallux limitus is.

I have written about this a lot, speculating that functional hallux limitus has many possible causes and that it may be better to conceptualize it as a nothing more that each person having a variable stiffness range of motion at the first metatarsophalangeal joint and that this may be related to the windlass mechanism. If this is the case then what we typically considered to be a functional hallux limitus is really the extreme of this variable stiffness and that functional hallux limitus probably exists as a continuum and not as an either/or entity.

My Interest in Concussion

Concussion is in the news a lot lately and protocols for their acute management have become stricter in most sports as more is known about the long term consequences of repeat concussions. For example, a third of kids who have a concussion develop long term mental health and emotional issues. New laws and rules are being implemented by sporting codes and others are under pressure to do more. I have previously blogged about why I think podiatrists should be concerned about concussion and there is a long thread at Podiatry Arena on concussion.

I see concussion as a major public health issue and podiatrists (and all health professionals) should be concerned and active in advocating on all public health issues (eg smoking, obesity, etc). We should be helping getting all the messages across.

The other reason is that post-concussion is that there is an increased risk for lower extremity injury. More than 30 or so studies now show that.

Finally, we are parents and members of the community and our kids play sport. We may need to step up and use the first aid skills if there is a knock to the head at sport.

I urge all Podiatrists to get involved and interested and become advocates for this public health issue.

Severs Disease / Calcaneal Apophysitis

This is a common topic I write about often. I wrote here about just how much I learnt about the condition when my own daughter got it and just how much that subsequently influenced my management. We did a PodChatLive on it with Alicia James and I published my unscientific study on it here.

Firstly, it should be called Calcaneal apophysitis and not Sever’s disease, but I still use Sever’s disease as that is way more common in the search engines when you want your writing to show up.

Secondly, as I said in my unscientific study, I not sure we can do much to help it. The big problem with Sever’s disease is that if you take 100 kids with and do nothing, x% will be a lot better next week. If you took another 100 and did something, then x% would be better next week, so did ‘something’ work or was it the natural history that was the reason for the improvement.

I know when you visit Podiatry Facebook groups and other social media and see discussions on Sever’s disease, so many have there views on what should be done. I have to fight myself really hard not to get involved in arguments, but I often want to ask them how do they know the treatment that they are advocating actually works and that the improvement that they are seeing is not just the natural history that you would expect to see. They actually have no way of knowing unless what they are advocating has been tested in a proper well controlled prospective randomized study.

So what do I do for Sever’s disease. Not a lot. Educate them on the nature of the condition and the natural history; discuss how to manage the loads and use a cushioned heel pad.

I am a big fan of the Archies Flip Flops

We call them “thongs” in Australia. The Archies footwear come with an arch support built into them. We sell Archies in our clinic in Melbourne and they sell well. Pretty much everyone who tries on a pair buys them They are that comfortable. What is useful about the Archies is that they can be used by those who need or have foot orthotics but want to occasionally wear this style of footwear.

The other great thing about these is that can be modifiable. I sometime get on the tools and make what I call a MOSI Archie modification for those with a more medially located subtalar joint axis. I made this video on the technique.

Archies

I also occasionally answer a question online about them!

The MOSI, the Kinetic Wedge, The Cluffy Wedge

I talk a lot during the Clinical Biomechanics Boot Camps about many different design features that get used in foot orthotics such as the MOSI, the Kinetic Wedge and the Cluffy Wedge to name just a few. They are all useful features and have their places depending on what affect you are wanting.

For example, the Cluffy Wedge is deigned to hold the hallux in a slightly dorsiflexed position. This tenses up the windlass mechanism in the foot and brings on that windlass effect earlier. That is only going to be useful if you want to or need to bring it on earlier. If the windlass mechanism is functioning fine, then the Cluffy Wedge is probably not going to make any difference. That does not stop some clinicians using it as a ‘cure all’ and using it in in most orthotic prescriptions. The Cluffy wedge or a similar foot orthotic modification is indicated when it indicated and not indicated when its not indicated.

Gait retraining for anterior compartment syndrome in runners

One big thing I get from running the Clinical Biomechanics Boot Camps is the feedback that I get when clinicians change their clinical practice based on what I teach on the course and its works!

One of these is the treatment of anterior compartment syndrome. My previous clinical experience in dealing with this problem is an almost 100% failure in its treatment. It really was a challenge. Anterior compartment syndrome is when the muscles expands its volume as it normally does on exercise and the fascial compartment that the muscle is in is particularly tight, so it hurts. Nothing really used to seem to help except the surgical outcomes were always pretty good.

In 2013, this study was published and I immediately started doing it in clinical practice and teaching about it in the Clinical Biomechanics Boot Camps. By changing from a heel strike to a more midfoot or forefoot strike with a lower touch down angle meant the activity in the anterior tibial muscle did not have to work so hard (but keep in mind that to do this requires other muscles to work harder and put them at increased injury risk if this is not done carefully).

This means the rationale was there. Even more surprisingly was that the results were often quite dramatic clinically. It worked. I enjoyed the feedback from course participants who went back to their clinics and tried it and contacted me to tell me it worked.

Arch Support in Footwear When There is Not Room for Arch Supports

So much of the use of foot orthotics is based on compromises. The ideal foot orthotic and the ideal foot orthotic prescription is often modified away from that ideal to take into account the footwear that they are to be used in. This is particularity a problem in things like tight football boots or ballet flats when you need some form of arch support. These types of shoes are not designed for any sort of support or foot orthotic to go into them. They are minimalist by design. Often what I do for these types of patients is use a self adhesive silicon gel arch support which takes up very little room, but does give some support. There is a little bit of trial and error to get the placement in the shoe right for comfort. It is less than ideal, but better than nothing.