Teleseminar on Gait→
/Wed TeleSeminar this week! Jul 11th, 2012 8:00 PM Eastern Time
Title: Chiropractic TeleSeminar Biomechanics 309
Location: 1 hr by telephone
Instructor: Waerlop/Allen, DC
Price: 19.00
Join Drs. Waerlop and Allen for this live seminar by telephone conference call with web interface. Lots of great video’s - always gets great feedback!
Neurocognitive Control in Movement Perception and Control
Neurocognitive control in dance perception and performance.
Department of Sport Science, Bielefeld University, Germany. bettina.blaesing@uni-bielefeld.de
Abstract: Dance is a rich source of material for researchers interested in the integration of movement and cognition. The multiple aspects of embodied cognition involved in performing and perceiving dance have inspired scientists to use dance as a means for studying motor control, expertise, and action-perception links. The aim of this review is to present basic research on cognitive and neural processes implicated in the execution, expression, and observation of dance, and to bring into relief contemporary issues and open research questions.
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What The Gait Guys have to say:
The abstract review above addresses six issues they discovered and investigated in dancers:
1) dancers’ exemplary motor control, in terms of postural control, equilibrium maintenance, and stabilization;
2) how dancers’ timing and on-line synchronization are influenced by attention demands and motor experience;
3) the critical roles played by sequence learning and memory;
4) how dancers make strategic use of visual and motor imagery;
5) the insights into the neural coupling between action and perception yielded through exploration of the brain architecture mediating dance observation; and
6) a neuroesthetics perspective that sheds new light on the way audiences perceive and evaluate dance expression.
As you have read from some of our previous blog articles, we have some experience in dance. We do this to make sure we are always pressing the edge of human sensorymotor development and learning. Dance has been one of the most complex body movement endeavors we have undertaken, more difficult than many of the complex movements in various sports. This is why we never have a problem recommending dance, gymnastics and pilates to our young patient’s parents who want their children to excel in any given sport. Fast, precise, assured and efficient foot work will take one far in athletics. It is why in basketball they talk so much about the importance of the first step off a dribble when confronting an opponent. The first step, when fast, precise, assured and efficient, will leave one’s opponent stunned and motionless as their savvy opponent effortlessly passes them by. Nothing teaches these foot skills better than dance in our experience. Just as Marquese displays above, mastering complex footwork leads to advanced body movement possibilities. And possibilities in sport are what separate the great from the good. The 6 points discussed above namely exemplary motor control, in terms of postural control, equilibrium maintenance, and stabilization, timing, on-line synchronization, sequencing of learning and memory, the advantages of strategic use of visual and motor imagery, the insights into the neural coupling between action and perception are all major advantages to the athlete who can put them into play at a higher level. And the more complex cross training of tasks that occurs, the greater likelihood that these issues are what will allow the cream to rise to the top in sport.
The Gait Guys
Gait Pathomechanics: Walking in a Pencil Skirt.
If you want more on this topic, Drs Allen and Waerlop go on a fun and informative rant on fashion, pencil skirts and high heeled shoes on Podcast # S1-E3 (Season1-Episode3), a soon to be released podcast episode.
Who knows why this video is even on Youtube. It is 6 minutes of this gal walking back and forth, so do not watch more than the first 60 seconds for anything exciting, trust us. Read the blog post and then come back to the video and see what we talk about. There are some severe gait compromises in a skirt like this, let alone with the high heel shoes accompanying the gait.
According to wikipedia:
The slim, narrow shape of a pencil skirt can restrict the movement of the wearer so pencil skirts often have a slit at the back, or less commonly at the sides. Sometimes a pleat, which exposes less skin, is used instead of a slit. The classic shoes for wearing with a pencil skirt are high heels,[3] with sheer stockings or tights. The predecessor to the pencil skirt is the hobble skirt, a pre-WWI fad inspired by the Russian Ballet. This full-length skirt with a narrow hem seriously impeded walking. The French designer Christian Dior introduced the classic modern pencil skirt in the late 1940s. The pencil skirt feels different from looser skirts, and can take some adjustment by the wearer in terms of movement and posture in order to manage it successfully. Walking needs to be done in short strides; entering and leaving a car gracefully takes practice; and when sitting the legs are held close together which some find restrictive (though others like the feeling of their legs being “hugged” by the skirt). Activities such as climbing ladders and riding bicycles can be very difficult in a pencil skirt. The pencil skirt is warmer due to the reduced ventilation, and is less likely to be blown up by gusts of wind.
The Gait Guys dialogue on pencil skirts :
Tie a rope or theraband around your knees, you will suddenly experience the short cute steps that this gals does devoid of almost all hip flexion and hip extension, both serious gait cycle restrictions.
Without hip flexion-extension the entire timing of the swing phase is off. No longer can there be adequate use of the obliquity of the pelvis and thus abdominals or contralateral leg swing to initiate supination and toe off.
Step and stride lengths are dictated by the tightness of the roap, and in this case the diameter and give of the bottom of the skirt. Not to mention the bloody complication added by the high heels !
- There is an unnatural oscillation of the pelvis due to the restrictions mentioned above.
The Pencil skirt: Never again will you be able to wear one and not notice its gait impairments. Nor will men be able to just watch the ladies in the skirts for the appreciation of beauty and style. Men, you will have much more to study now, you just may hate us for your undying need to evaluate the biomechanics in skirt wearers forevermore ! Just be sure you do not abuse this new evaluation superpower as an excuse to your spouse to watch girls walk by. We are not responsible for abuses of acquired superpowers. And although we many have actually just become your new heros, just remember, with great powers come great responsibilities.
Once the website launches you will find our new product, “pencil skirt training noose” on our online store. $50 for the finest of roap loops !
There is so much more on this topic in Podcast #3 . Be sure not to miss it. We will launch it here on the blog and on our Facebook page and in iTunes once we get permissioned by Apple.
Shawn and Ivo, your new superheros of gait. Gait Fashonistas, perhaps we have a purpose and calling in the fashion industry !
Podcast #1: S1E1 (Season 1, Episode 1)→
/OK gang, here we go ! They are finally launched !
THE GAIT GUYS EXPERIENCE PODCAST has arrived !
http://thegaitguys.libsyn.com/ (click on the small circle beside the word “Pod” beside the title)
Please be patient while we work out the audio bugs over the first 2-3 podcasts (there is some irritating reverb on this first one). We have new studio quality mics on the way, better sound cancelling earphones and we are looking at some compressors and what not to get the sound quality up. It is hard doing this through a virtual studio separated half way across the country. So, be patient with us for this brief time.
But most of all, Enjoy !
*** IMPORTANT: There are 2 links below.
Be sure to click below to grab our RSS feed so you never miss a podcast. The second link below will have our session notes for the podcast so you can see the topics at hand, follow the case studies, and have all links to videos, articles at your disposal so you do not have to reach for a pen to jot them down. All you have to do is listen and enjoy ! If you have emailed us questions or presented us with your case problems, you will find most if not all of your email typed out (ID protected of course) in the session notes.
We have pods 2-4 done already. The have better stories and we have worked out some of our anxieties about screwing up an hour long recorded mid way ! So, give us a few listens before you start firing off recommendations. We will want them, but most of the bugs on the first 2-4 podcasts you will find resolved. So by podcast 5 we will want your input and feedback !
http://thegaitguys.libsyn.com/rss
Here is a website where all of our podcasts will be housed and launched from. You can find all of our session notes here as well.
http://thegaitguys.libsyn.com/
We will have this all shipped over to iTunes soon so you can load them up to your ipod and mp3 players to we can be a part of your journey into work every day, or hand out with you while you cut the lawn, cook dinner or whatnot. So, Hang tight ! It is all coming.
PS: we talk about the website launch in this first podcast. It is next on our list. It is 95% done. Hang tight !
Now, if we could just quit our day jobs we would have had all this done long ago !
Thanks for your patience everyone !
Being on the airwaves we are now one step closer to intergalactic domination !
Shawn and Ivo, The Gait Guys
Is Barefoot more economical ?→
/Researchers at England’s Northumbria University analyzed the gait and oxygen uptake of 18 recreational and elite runners performing a series running tasks both barefoot and shod.
Dr. Michael Wilkinson, lead researcher and avid barefoot runner determined the following in their study:
- a significant saving in energy from taking off running shoes
- mechanical differences in the foot strike patterns (shod runners did more heel strike, unshod were more midfoot striking)
- there were immediate foot strike changes in previously shod runners who suddenly changed to unshod foot strike
- there is less oxygen use during barefoot running compared to running shod at the same speed. Hence improved running economy.
Characteristically, skilled unshod runners have a distinctive running gait utilizing:
- mid-foot landing
- shorter stride lengths
- faster stride rates
- reduced ground contact time
- lower impact force and loading rates which dampens injury inducing forces
- reduced oxygen utilization. The 6% improvement in economy was the same as that previously reported after a nine-week training program for shoe-wearing runners, who also enjoyed a 3% improvement in running performance.
Click on the link above for the Science article.
More research on Forefoot Running: Forefoot Varus and the toe extensor muscles.
/Lately we have all seen much in the news about the forefoot strike loading in runners and many of the proposals and rebuttals regarding injury rates. Our dialogue less than 2 weeks ago on some of Lieberman’s recent comments (our blog article “Dear Dr. Lieberman”, click here) seem to be ringing true again. Here are just two more insightful and important studies when it comes to looking at some of the proposed ideas and causes of forefoot varus. Naturally, a thinking mind would wonder if some of these weaknesses in anterior and posterior tibialis muscles as well as extensor toe musculature, as proposed in just these 2 articles, are causal to the forefoot injuries that seem inevitable as Lieberman seems to suggest (again, see our blog post). Naturally, weaknesses and poor motor patterns of some or all of these muscles is going to create and insufficient and possibly inefficient and pathologic forefoot loads because of the forefoot varus foot type these muscular imbalances can functionally produce. We have been pounding sand on this issue for years but still no one listens. The medial research, as evidenced here is supportive of our theories and everyday clinical findings.
To summarize, ONCE AGAIN, not everyone is suited or possibly ready for forefoot load/contact/strike running. And if you have injury or problems in doing so, don’t blame your minimalist shoe……. it is either a foot type that needs functional repair or a foot type that is fixed an must opt for midfoot strike.
There is SO MUCH MORE to this game than just strap on some minimalist shoes and start forefoot loading your way on your next run. Buyer beware !
Shawn and Ivo…….. the gait guys……..two guys who are “Gandhi’d” regularly.
“First they ignore you, then they laugh at you, then they fight you, then you win.”
- Mahatma Gandhi
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http://www.ncbi.nlm.nih.gov/pubmed/20307453
Foot (Edinb). 2009 Jun;19(2):69-74. Epub 2008 Dec 31.
Foot varus in stroke patients: muscular activity of extensor digitorum longus during the swing phase of gait.
Reynard F, Dériaz O, Bergeau J.
Clinique romande de réadaptation, SUVA Care, Av. Gd-Champsec 90, Sion, Switzerland. fabienne.reynard@crr-suva.ch
Abstract
CONCLUSIONS: The activity of extensor digitorum longus muscle during the swing phase of gait is important to balance the foot in the frontal plane. The activation of that muscle should be included in rehabilitation programs.
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http://www.ncbi.nlm.nih.gov/pubmed/16882899
J Bone Joint Surg Am. 2006 Aug;88(8):1764-8.
The contributions of anterior and posterior tibialis dysfunction to varus foot deformity in patients with cerebral palsy.
Michlitsch MG, Rethlefsen SA, Kay RM.
Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
Abstract
RESULTS: The muscular contributor to varus deformity was the anterior tibialis in thirty feet, the posterior tibialis in twenty-nine feet, both the anterior tibialis and the posterior tibialis in twenty-seven feet, and another contributor in two feet. Seventy feet had varus deformity during both stance phase and swing phase. Of these seventy feet, twenty-five exhibited dysfunction of the anterior tibialis, twenty exhibited dysfunction of the posterior tibialis, and twenty-three exhibited dysfunction of both muscles. Therefore, the timing of varus was not predictive of the contributing muscle or muscles.
CONCLUSIONS: The current study demonstrated a higher prevalence of anterior tibialis dysfunction, both alone and in combination with posterior tibialis dysfunction, as a contributor to pes varus in patients with pes varus and cerebral palsy than had been reported previously. Dynamic electromyography provides clinically useful information for the assessment of such patients.
MORE compensations for short legs…
We remember from 2 weeks ago, the week before, AND last week, there at least SIX common compensations for a short leg.
We spoke about circumducting the long leg last time. Once again, here is the list
- pronation of the longer side, supination of the shorter
- leaning to he shorter leg side
- circumduction of the longer leg around the shorter
- hip hike on long leg side (seen as contraction of hip abductors, obliques and quadratus lumborum on short leg side)
- excessive ankle plantar flexion on short side
- excessive knee bend on the long leg side
Lets look at “hip hiking” of the longer extremity today. Hiking the hip allows one to create enough room (hopefully) to get that long leg through without dragging on the ground. Again, it makes no difference if the leg is functionally or structurally short, the body still needs a strategy to move around the longer leg.
This gal in the video has cerebral palsy (CP), affecting the left side. She has a short R leg and hikes the L pelvis pelvis up to get it to clear (she has L g med weakness due to the CP)
Watch the above video a few times to see what we are talking about. You can really see it when she is walking toward you.
Remember here is that what you are seeing is the compensation, not necessarily the problem. When one leg is shorter, something must be done to get the longer leg through swing phase.
Hip Hiking. Not quite the “Walk in the Woods” Bill Bryson was talking about, but yet another compensation for a short leg.
Ivo and Shawn. …bald, good looking, geeky…… The Gait Guys
Neuromechanics Weekly: How does appropriate movement diminish pain?
We talk about proper (or should we say appropriate) movement (including gait) inhibiting or diminishing pain. So, how does that happen?
Above on the left is a great diagram that we will work through.
You are looking at a cross section of a spinal cord (We can hear the groans already!) We remember that the dorsal horn (posterior part) is sensory and the ventral horn (front) is motor. In between them (the lateral horn) is autonomic (this runs automatized body functions such as your heart, lung, guts, etc).
Small nerve fibers subserve pain. These are the A delta and C nerve fibers. “Small” refers to fiber diameter of the nerve. These nerves are where pain stimuli enters the spinal cord; they enter the sensory dorsal horn and synapse/connect there with the next neuron in line that takes the sensory message up the spinal cord to the brain to tell you about the pain including its intensity, location etc. Pain can result from tissue damage or injury (which can be due to, or the result of, poor biomechanics).
Large diameter nerve fibers subserve sensations like touch, pressure, vibration, muscle spindles (muscle length) and golgi tendon organs (muscle tension/load). These fibers also enter the sensory dorsal horn, but they do not synapse immediately, unlike pain fibers. They ultimately travel up to the top of the brainstem or cerebellum to coordinate information with other data your brain is processing. They send a branch (or collateral) to an inhibitory neuron, which excites the inhibitory neuron. Thus, if you excite an inhibitory neuron, it does it’s job and inhibits the propagation of an impulse. In this case, it inhibits the pain impulse from traveling to the cortex. So pain is inhibited. Appropriate biomechanics excite the largest population of receptors and provide the most effective response.
Now look at the diagram on the right. It is a simplified schematic of the one on the left, with detail of the connections. Note that the LARGE FIBERS (from joint mechanoreceptors, spindles, muscles, etc) EXCITE the inhibitory interneuron (which would inhibit it). Also note that the SMALL FIBERS INHIBIT the inhibitory internuron (which would excite it!)
There you have it. Clear as mud? Go through some of our old posts on receptors and FEEL THE PAIN (parts 1, 2, 3+4) and come back to this and read it again. You know you want to be a geek, so go ahead!
The Gait Guys: Geeks on many levels. helping you to presynaptically inhibit pain on a daily basis, through better movement.
Case of the Week: Rib Pain while Running: Part 2
Welcome back. Glad you picked choice d (or maybe you had a pint anyway)
Assessment: This patient has a significant difference in the length of her legs; her left leg being short, right leg being longer. The right ilia is rotated posteriorly (thus the tissue fold) in an attempt to shorten the extremity and the left ilia is rotated anteriorly, in an attempt to lengthen the leg. This is putting the abdominal external obliques in a lengthened and shortened position, respectively. The right is short weak and the left is long (stretch). The obliques attach to the lower ribs 5-12 (for external) and ribs 10-12 (for the internals).
The psoas muscle takes its origin form the lumbar vertebral bodies and inserts on the lesser trochanter of the femur. Due to the poterior rotation of the right ilia, it has been lengthened over time (thus the difference in hip extension) and is stretch weak on the right.
So why only on the right and during running?
due to the anatomical leg length difference, the right oblique has shortened over time. Running (forced inspiration and expiration) causes us to use some of our accessory muscles of respiration (obliques, intercostals, serratus posterior superior and inferior, sternocleidomastoid, scalenes. Remember that for quiet respiration, only the diaphragm is used for inspiration; passive tension in muscles for expiration).
Also, the stride length will be increased on the longer leg side (ie when the L leg is in swing and R in stance); this put additional stretch on the R iliopsoas and R abdominal obliques.
iliopsoasthe
Treatment Plan: We placed a 3 mm lift in her left shoe. We treated with manipulative therapy of the lumbar spine. She was given the nontripod, side bridge, cross/crawl quadruped and hip flexor stretch with side bending exercises to perform on a daily basis. She felt better post treatment.
Case of the Week: Rib Pain while Running: Part 1
This 39 year old woman presents with with rib pain, pointing to right ribs. First time it “went out” 1 ½ year ago, second time a year ago and recently two weeks ago. It is usually related to running with pain the day of and day after it is acute; it hurts to lie on her back or roll onto that side or breathe deep. She seems to do best when she is semiflexed on her knees. Stretching can take the edge off. When she has an acute episode, it usually lasts about a day.
She is very physically active and works out almost everyday. She runs triathlons and Ironman’s (or Ironwoman’s in this case), and generally is in good shape.
Above is what you see physically (hover mouse over each picture) and here are her exam findings:
She is 5’ and weighs approx. 105 pounds. BP 100/72 left, pulse ox 94, pulse 52. Lungs auscultate clearly, normal heart sounds, abdomen non tender and normal to percussion and auscultation.
Viewed from posterior in a standing position, she had increased tibial varum bi-lat., right greater than left, right hip had posterior rotation, less space between iliac crest and rib margin right hand side. No tenderness noted over the obliques or lower ribs left hand side. She had a loss of lateral bending to the left L2 through L4 negative theta-z stress.
She has a L left short leg (tibial) 5 mm, bi-lat. external tibial torsion left greater than right. There is weakness of the abdominal internal and external obliques bi-lat. as well as iliopsoas, R > L. There was point tenderness at the R lesser trochanter; active and passive hip extensoin was 10 degrees right, 15 degrees left.
Question: What is your assessment and what are you going to do?
a. do not know, go have a beer
b. do not know, go have 2 beers
c. do not know, do not drink beer, have a double latte after reading Fridays post and try not to spill it
d. reply to this post, think about it and check back later to see what The Gait Guys have to say