Leg length discrepancies and total joint replacments.

5mm cut off ?  MaybeYou are likely to come across hip and knee arthroplasty clients (total joint replacements). When they take a joint out and replace it with a new one, it can be a true challenge to restore leg lengths to equality side to side. Problems often arise down the road once gait is resumed and rehabilitation is completed. It can take time for the leg length discrepancy (LLD) to begin to create compensatory problems. This article seems to suggest that 5mm is the tipping point where gait changes becoming a problem are founded. Other sources will render different numbers, this article found 5mm. The authors found that both over- and underrestoration of leg length/offset showed similar effects on gait and that Gait analysis was able to assess restoration of biomechanics after hip replacement.  I would chose to use the word “change” over restore, since the gait analysis is merely showing the deployed strategies and compensations, never the problem.  But it is a tool, and gait analysis can be a decent tool to show “change”.*Remember, it is not always a product of true length, it can come from the pelvis posturing and/or from the acetabular orrientation, which can be a postoperative sequella. One cannot over look  acetabular inclination, anteversion and femoral component anteversion/retroversion issues.Just remember, before you start making LLD changes with inserts, cork, orthotics etc be sure that you have restored as best as possible, pelvis-hip-spine mechanics because changes here can reflect as a mere leg length discrepancy. And it goes the other way as well, a LLD can cause those changes above.

* Just use your brain and don’t just lift the heel, give them a full sole lift. Heel lifts for this problem are newbie mistakes. Don’t be a newbie.

– Dr. Shawn Allen

Leg length and offset differences above 5 mm after total hip arthroplasty are associated with altered gait kinematicsTobias Renkawitz, Tim Weber, Silvia Dullien, Michael Woerner, Sebastian Dendorfer, Joachim Grifka,Markus Weber
http://www.gaitposture.com/article/S0966-6362(16)30148-5/abstract?platform=hootsuite

Podcast 107: Unilateral Training: Warping the Nervous System

Plus: Changing an existing orthotic to make it work, Meniscal tear truths, Shoe Insole truths, Plantar Pressures

Show Sponsors:

softscience.com
Altrarunning.com

Other Gait Guys stuff

A. Podcast links:

http://traffic.libsyn.com/thegaitguys/pod_107f.mp3

http://thegaitguys.libsyn.com/episode-107-0

B. iTunes link:
https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

C. Gait Guys online /download store (National Shoe Fit Certification & more !)
http://store.payloadz.com/results/results.aspx?m=80204

D. other web based Gait Guys lectures:
Monthly lectures at : www.onlinece.com type in Dr. Waerlop or Dr. Allen, ”Biomechanics”

-Our Book: Pedographs and Gait Analysis and Clinical Case Studies
Electronic copies available here:

-Amazon/Kindle:
http://www.amazon.com/Pedographs-Gait-Analysis-Clinical-Studies-ebook/dp/B00AC18M3E

-Barnes and Noble / Nook Reader:
http://www.barnesandnoble.com/w/pedographs-and-gait-analysis-ivo-waerlop-and-shawn-allen/1112754833?ean=9781466953895

https://itunes.apple.com/us/book/pedographs-and-gait-analysis/id554516085?mt=11

-Hardcopy available from our publisher:
http://bookstore.trafford.com/Products/SKU-000155825/Pedographs-and-Gait-Analysis.aspx

________________________

Show Notes:

Running helps mice slow cancer growth
https://www.sciencedaily.com/releases/2016/02/160216142825.htm

The future of Wearables
http://readwrite.com/2016/02/19/future-of-wearables

mensicus surgery is dead ?
http://www.regenexx.com/should-i-have-meniscus-surgery/#

Why you should be training your CNS
http://www.outsideonline.com/2055066/cross-educate-your-body#article-2055066

The business of insoles
http://www.outsideonline.com/2057156/business-insoles-support-system-or-super-rip

Altered plantar pressures
http://link.springer.com/article/10.1007%2Fs00167-016-4015-3

1st met pain in an orthotic?

This patient came in with pain at the base of the first metatarsal that she believed was related to her orthotic. The first picture shows the foots relationship to the orthotic. Notice how the sesamoid bones and distal aspect of the first metatarsal under lap the orthotic shell. In other words, the shell is longer than her foot. When she dorsiflexes her big toe, she’s hitting the distal of the orthotic.

The next view shows the orthotic with a typical first ray cutout. Notice how far forward the shell of the orthotic goes (next picture). I have placed a pen pointing to the area where the orthotic shell is too long.

In addition to reviewing her first ray descending exercises, a simple fix was to grind back the orthotic shell and be careful to bevel the edge so that it was not hitting the sesamoids and it did not impinge upon the descending first ray. I have placed a pen where the cut out now is (pre and post gluing in the pictures). The cork underlying the base of the first ray was also ground away (last picture)

A simple fix for a common problem. Make sure that your orthotic shell lengths fall just short of the 1st ray and not impinge on the sesamoids!

A test question from Dr. Allen, see how you do with this photo critical thinking.

When you walk on the beach you are on a slope. The leg closer to the water naturally drops down to a lower surface. 

Here is the game …  to keep the pelvis level on the horizon, one would have to:

a. shorten the water side leg

b. lengthen the water side leg

c. pronate the water side leg

d. supinate the water side leg

e. lengthen the beach side leg

f. shorten the beach side leg

g. pronate the beach side leg

h. supinate the beach side leg

i. externally rotate the water side leg

j. internally rotate the water side leg

k. externally rotate the beach side leg

l. internally rotate the beach side leg

m. flex the water side hip

n. extend the water side hip

o. flex the beach side hip

p. extend the beach side hip

******Ok, Stop scrolling right now !!!!!  

List all the letters that apply first.

You should have many letters.  *** And here is the kicker for bonus points, the letters can be unscrambled to spell the name of one of the most popular of the Beatles. Name that Beatle.

.

.

.

don’t look, figure it out before you scroll down further. It is important you try to work through the question and its foundational principles.

.

.

.

.

.

.

Answer: B, D, F , G, I ,L , N, O

* now, more importantly, make sure you think of these issues in all your clients with leg length discrepancies, both anatomic and function and when the pelvis is not level. This is the most important take away from today’s test question. If you got the answers correct, you have the knowledge to implement. If you did not get the answer correct, you need to hammer down the HOW and WHY of the answer before you start playing with people’s bodies putting in heel lifts (boooo), sole lifts, orthotics, postings etc. If you do not have the foundation to play by the rules, you should not be playing.

ok, we were messing with ya on the Beatles thing. Sorry.

Dr. Shawn Allen

Eliminating the fake out of ample ankle rocker through foot pronation in the squat and similar movements:  How low can you go ? 

This is a simple video with a simple concept. 

* Caveat: To avoid rants and concept trolling, am blurring lines and concepts here today, to convey a principle. Do not get to tied up in specifics, it is the principle I want to attempt to drive home.  What you see in this video is clearly more lunge/knee forward flexion rather than hip hinge movement. However, keep in mind, that this motion does occur at the bottom of many movements, including the squat. 

You can achieve or borrow what “appears” to be more ankle dorsiflexion, a term we also loosely refer to as ankle rocker, through the foot, foot pronation to be precise. Do not mistaken this extra forward tibial progression range as ankle rocker mobility however. When you need that extra few degrees of ankle dorsiflexion deep in your squat, or similar activities, you can get it through your foot. Often the problem is that you do not think that is where it is coming from, you might just think you have great ankle mobility.  Many deep squatters are borrowing those last few degrees of the depth of the squat from the foot. This is not a problem, until it is a problem.  Watch the video above.  Why ? Because when the foot pronates and begins to collapse (hopefully a controlled collapse/pronation) the knee follows. Forcing the knees outward in a squat like some suggest is a bandaid, but I assure you, the problem is still sitting on the table. 

Go do a body weight squat with the toes up like in this video. Toes up raises the arch from wind up of the windlass and increased activity of the toe extensors and some assistance from the tibialis anterior and some other associated “helper” muscles.  When the arch is going up, it cannot go down. So, you raise your toes and do your squat. This will give you a better, cleaner representation of how much mobility in your squat/lunge/etc is from ankle dorsiflexion, knee flexion and  hip flexion. You can cheat and get some from the foot. The foot can be prostituted to magnify the global range, and like I said, this is not a problem until it IS a problem.   We know that uncontrolled and unprotected increases in foot pronation can cause a plethora of problems like plantar tissue strain, tibialis posterior insufficiency and tendonopathies, achilles issues, compression at the dorsum of the cuneiform bones (dorsal foot pain) to name a few. This dialogue however is not the purpose of this blog post today. You can read more about these clinical entities, proper foot tripod skills and windlass mechanics on other blog posts on this site. 

Today, we just wanted to bring this little “honesty” check to your awareness. Has been a staple in my clinic for over a decade, to help me see where limitations are and to show folks how they can cheat so much through the foot. Go ahead, try it yourself, see how much you use your foot to squat further if you have end range mobility issues in the hips, knees or ankles.  The foot is happy to give up the goat, it just doesn’t know the repercussions until they show up. 

So, lift your toes, do a full squat. Go as low as you can with good form with the toes up.  Then, at the bottom of the squat or the bottom of  your clean mobility, suddenly drop your toes and let the arch follow if it must. Here is the moment of truth, at that moment the toes go down, feel what happens to the foot, ankle, tibial spin, knee positioning, pelvis posture changes. Careful, these are subtle. You may find you are using foot pronation more that you should, more than is safe.  Now try this, bottom out your cleanest squat as you regularly would, and at the bottom, raise your toes and try to reposition the foot arch and talus height. In other words, reposture your foot tripod, see how difficult this is if you can do it at all. Perhaps you will find your toe extensors are too weak to even get there.  This is how we cheat and borrow. We should not make it a habit, it should be used when we need it, but it should not be a staple of your squatting diet, it should not be a regular event where you prostitute sound biomechanics.  Unless you wish to pay for it in some way.  What should happen is that you should be able to bring your toes down and not let the arch follow, but that is a skill most have not developed. It is a staple move in your clients’ movement diets.

Does all this mean you should squat with your toes up ? No, but it may serve you well in awareness, evaluation, and looking for potholes and power leaks. At the very least, give it some thought and consideration. You may see some smiles and have some lightbulb moments between you and your athletes and clients. 

Plan on blocking this foot pronation range with an orthotic ? How dare you ! At least try to do it through reteaching this and the tripod skill first. Give your a client a chance to improve rather than a bandaid to cope. 

Dr. Shawn Allen, one of the gait guys

Falling hard; Using supination to stop the drop.

“One thing, affects all things. One change necessitates global change. The more you know, the more you will see (and understand).  The more you know, see and understand, the more responsible you will and should feel to get it right and the more global your approach should become. If your head does not spin at times with all the issues that need to be juggled, you are likely not seeing all the issues you should be seeing.” -Dr. Allen (from an upcoming CME course)

This is a case that has been looked at before but today with new video. This is a client with a known anatomic short leg on the right (sock-less foot) from a diseased right hip joint.  

In this video, it is clear to see the subconscious brain attempting to lengthen the right leg by right foot strike laterally (in supination) in an attempt to keep the arch and talus as high as possible.  Supination should raise the arch and thus the resting height of the talus, which will functionally lengthen the leg.  This is great for the early stance phase of gait and help to normalize pelvis symmetry, however, it will certainly result in (as seen in this video) a sudden late stance phase pronation event as they move over to the medial foot for toe off. Pronation will occur abruptly and excessively, which can have its own set of biomechanical compensations all the way up the chain, from metatarsal stress responses and plantar fasciitis to hip rotational pathologies.  It will also result in a sudden plummet downwards back into the anatomic short leg as the functional lengthening strategy is aborted out of necessity to move forward.  

This is a case where use of a full length sole lift is imperative at all times. The closer you get to normalizing the functional length, the less you need to worry about controlling pronation with a controlling orthotic (controlling rate and extent of arch drop in many cases). Do not use a heel lift only in these cases, you can see this client is already rushing quickly into forefoot loading from the issues at hand, the last thing you should be doing is plantarflexing the foot-ankle and helping them get to the forefoot even faster !  This will cause toe hammering and gripping and set the client up for further risk to fat pat displacement, abnormal metatarsal loading, challenges to the lumbricals as well as imbalances in the harmony of the long and short flexors and extensors (ie. hammer toes). 

How much do you lift ?  Be patient, go little by little. Give time for adaptation. Gauge the amount on improved function, not trying to match the right and the left precisely, after all the two hips are not the same to begin with. So go with cleaner function over choosing matching equal leg lengths.  Give time for compensatory adaptation, it is going to take time.  

Finally, do not forget that these types of clients will always need therapy and retraining of normal ankle rocker and hip extension mechanics as well as lumbopelvic stability (because they will be most likely be dumping into anterior pelvic tilt and knee flexion during the sudden forefoot loading in the late midstance phase of gait). So ramp up those lower abdominals (especially on the right) !  

Oh, and do not forget that left arm swing will be all distorted since it pairs with this right limp challenge. Leave those therapeutic issues to the end, they will not change until they see more equal functional leg lengths. This is why we say never (ok, almost never) retrain arm swing until you know you have two closely symmetrical lower limbs. Otherwise you will be teaching them to compensate on an already faulty motor compensation. Remember, to get proper anti-phasic gait, or better put, to slow the tendency towards spinal protective phasic gait, you need the pelvic and shoulder “girdles” to cooperate. When you get it right, opposite arm and leg will swing together in same pendulum direction, and this will be matched and set up by an antiphasic gait.

One last thing, rushing to the right forefoot will force an early departure off that right limb during gait, which will have to be caught by the left quad to dampen the premature load on the left. They will also likely have a left frontal plane pelvis drift which will also have to be addressed at some point or concurrently. This could set up a cross over gait in some folks, so watch for that as well.

“One thing, affects all things. One change necessitates global change. The more you know, the more you will see (and understand).  The more you know, see and understand, the more responsible you will and should feel to get it right and the more global your approach should become. If your head does not spin at times with all the issues that need to be juggled, you are likely not seeing all the issues you should be seeing.” -Dr. Allen (from an upcoming CME course)

Shawn Allen, one of the gait guys.

Custom orthotic or Sham for mid tendon achilles tendonopathy? It doesn’t seem to matter.

This study prescribed eccentric calf exercises along with either a custom or “sham” foot orthosis for 140 people who were randomized as to which group got the real goods and which one did not.  A Victorian Institute Sports Assessment-Achilles questionairre was given at baseline, 1, 3, 6 and 12 months. No statistically significant difference between the groups.

Hmmm..

We wonder just what were the custom and sham like? When we use orthoses, we use full arch contact devices. Perhaps the type of orthosis makes a difference? What has been your experience?

Munteanu SE, Scott LA, Bonanno DR, Landorf KB, Pizzari T, Cook JL, Menz HB.  Effectiveness of customised foot orthoses for Achilles tendinopathy: a randomised controlled trial.
Br J Sports Med. 2015 Aug;49(15):989-94. doi: 10.1136/bjsports-2014-093845. Epub 2014 Sep 22.