Hips, joint resurfacing and stem cells.

Things are moving fast in the research world. We need to keep up with our readings even though it seems like trying to drink from a firehose at times. These things will likely be upon us in a mere blink.

"scientists have programmed stem cells to grow new cartilage on a 3-D template shaped like the ball of a hip joint. What's more, using gene therapy, they have activated the new cartilage to release anti-inflammatory molecules to fend off a return of arthritis."

We have always encouraged our clients that joint replacements are the choices at the end of the road when it comes to options.

We must maintain mobility and stability and clean function and always drive the client status first into good quality of motion over power and speed. Without the proper assessment of function we can get these things backward because of skilled compensation patterns. It is highly suspect that many injuries occur because of increased strength, load, speed, power etc being born atop corrupt movement pattern foundations. After all, humans are great compensators. It is suspect that these mistakes are what lead young clients down expedited joint "wear and tear" paths, sometimes leading to joint replacements at a sub 60 year age if not sooner. This kind of research as described here in this article could be the life saver those folks are looking for. However, this should never take the place of abiding by the guidelines discussed above. There are principle rules, but as in life, many of us forget that they do not apply to us because we are "an exception".

Scientists develop new way to resurface arthritic hip joint

http://www.news-medical.net/news/20160719/Scientists-develop-new-way-to-resurface-arthritic-hip-joint.aspx

Scars of evolution

So this week has been much about the glutes. We stepped back earlier today into the evolution of bipedalism and some theories around glutes and what might have pushed us upright from 4 limbs onto two. And now as the grand karma of the internet has been listening in ....... we find this:

Lucy remains one of the most famous discoveries in paleontology. ""Her death, on the other hand, has been a mystery. Now, after poring over the celebrated bones, a team of scientists has concluded that Lucy died most unceremoniously: from a long fall out of a tree. If they are right, the discovery could yield an important clue to how our ancestors evolved from tree-dwelling apes into bipeds that walked the African savanna."

Listen to our 13 minute Podcast "shorts":Evolution of Upright Bipedal Gait & Glute Development released today. It is interesting stuff. Link:https://tmblr.co/ZrRYjx2BTf6mR 

A 3.2-Million-Year-Old Mystery: Did Lucy Fall From a Tree?

-By Carl Zimmer

http://www.nytimes.com/2016/08/30/science/lucy-hominid-fossils-fall.html?_r=1

A Blood flow restriction lesson from a yo-yo champ.

This is the finger of a professional yo-yo'ist. Extreme blood flow restriction damage.
We don't have a problem with the blood flow restriction training and therapy that is all the rage these days (*caveat: see below), though we don't hold a lot of value in it, we suppose things have their place. 
Our point today with this photo, just keep in mind what the heck you are doing to the stuff you cannot see. We continue to search for research that might come out in time showing arterial damage or possible clot formation in folks who over do Blood Flow restriction stuff too long, too tight, too often. Stuff is getting compressed and we wonder if arterial wall damage might be something we see down the road ??? Who knows, just thoughts. We are not trying to be alarmists by any means, it is just the kinda stuff we think about.
Sure, this is an angiogram of the permanently ruined veins in the finger from years of string soft tissue restriction, certainly an extreme case ! We just thought it was interesting and reminds us all that we need to keep in mind what our therapies are doing to the tissues beneath and what the activities of our clients can do over a long period of time. We don't have any pro-yo-yo folks in our office, maybe you do, and if so, educate

Foot skills: Edgework

From August 28, 2016 facebook post

* VIDEO: About 4-5 years ago some of you that have been with us for awhile will recall that i studied some latin and smooth ballroom dance for a few years. It was humbling to say the least. There are so many reasons why men suck at dancing. But, I have never been one to stray away from fearful and humbling experiences. I enjoy being curious and trying hard things and i am ok with looking like a fool to get an edge on wisdom seeking. This dance thing was the hardest thing i have ever done, the pros make it look easy, but it is hard. Movement, coordination, timing, rhythm, memorizing steps and principles, then learning to lead a partner through all that SILENTLY ! but one of the hardest things to learn was how to use the whole body to create movement. Dancing is whole body, latin dancing is a workout, and the core gets smashed when done right. There is a reason dancers have amazing bodies, because this stuff is hard ! One day one of the male coaches came over to me and said something resembling "you are not reacting into the floor with your feet, you have to feel the inside and outside edges of your rear, mid and forefoot at any one moment of time. If you cannot get that right, you cannot properly engage the leg muscles, hips and certainly not your core". He was right. I had no idea how to move. He then said, "go home, but on some socks and polish your floors, reacting into, and then off of, the floor. When you begin to feel your leg muscles and learn that the feet can be used in so many ways other than walking, things most people never even come close to in sports, you will be ready to START." This was what happened after one week of reacting into the floor, I came to name it, "EDGEWORK". I was learning to use the inside and outside edges of my rear, mid and forefoot, sometimes on the opposite sides of the body, pronating at times through the right rear foot while supinating through the left forefoot etc. This is why I laugh to myself when i see people posting what they call holy grail "foot exercises" on the internet. Much of it is novice stuff, but admittedly that is where most people have to begin, and should begin. This was just one reason I appreciated learning 10 different dances, from cha cha and jive which had extremely fast and agile foot work, to rhumba and salsa and their complicated foot work into the floor, and then dances like foxtrot or waltz that required an entirely different kind of footwork, skimming and floating across the foot with grace. Oh, and did i mention leading a lady about the floor, silently with just body jestures and gentle hints of pressure. Oh, and to music, on time, in rhythm etc. This was a journey in which i gave zero f#@&ks about about what people thought when they knew i was taking dancing lessons, because I knew I was learning to move and use my body like few others even remotely had a clue about, and likely never will. Enjoy my silly little FOOT EDGEWORK video i shot for this coach, so he could see what i had been able to do in just a week. You will see inside edges, outside edges, skimming, floating, pressuring into the floor, directional changes, pivots etc. From here, my journey into movement took a giant leap forward. I began to truly understand how the foot worked on the ground, truly "worked" and how that would translate into hip rotation, core engagement, upper body turning, spinning, posture, arm movements, glute and calf use, peroneal stability for the lateral ankle and many more things. There is a reason why some of the greatest athletes in sports took on dancing and ballet to improve their understanding and grace of movement to their chosen field. Because it was an edge no one else willing to embrace. Go ahead laugh at the silly video, i sure did. I just found it while purging computer files and immediately put the wool socks back on and went to polish the floors. Come on men, help keep the house floors sparkly clean like mine, give them a shine :) Oh, and thanks Bruce Lee, Hong Kong Cha cha champion for making it ok to follow you. You can take that to the bank Connor McGregor. (*the silliness begins about 10seconds into the clip, give it a sec)
- Dr. Shawn Allen, the other gait guy

https://www.facebook.com/thegaitguys/videos/1310391195667219/

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Concussions and increased risk for musculoskeletal injury.

Concussion Increases Odds of Sustaining a Lower Extremity Musculoskeletal Injury After Return to Play Among Collegiate Athletes. -Brooks et al.

Perhaps we need to be paying far more attention to the musculoskeletal injuries in our contact sport athletes. We need to bring to light some important facts to our athletes (and their parents!).

From the Nauman Purdue football study:
"The worst hit we've seen was almost 300 Gs," Nauman said. A soccer player "heading" a ball experiences an impact of about 20 Gs." 
Here is what we say: now add 20 soccer headers in a week of game and practice. Or take 20 submaximal football tackles, in a week of game and practice. You do the math.

Concussions have been now shown to cause abnormalities in brain and motor functioning. These issues can last long after perceived clinical recovery. "Recent work suggests subtle deficits in neurocognition may impair neuromuscular control and thus potentially increase risk of lower extremity musculoskeletal injury after concussion."
Do NOT underestimate the impacts of a single concussion, and certainly NEVER in a second impact (Second Impact Syndrome (SIS)). SIS can at worst, lead to death within minutes, so certainly it can lead to impaired neuromuscular control. Our current society continues to ignore the immense long lasting effects of head injuries, even minimal ones. We continue to allow young developing brains to partake in football, soccer, and other jarring sports. Yes, we cannot live in a vacuum, but we can live in awareness and wise choices.

Facts: 
The 2 year Purdue Study of high school football players suggested that concussions are likely caused by many hits over time and not from a single blow to the head, as previously believed. "Over the two seasons we had six concussed players, but 17 of the players showed brain changes even though they did not have concussions," Talavage said. "The most important implication of the new findings is the suggestion that a concussion is not just the result of a single blow, but it's really the totality of blows that took place over the season," said Eric Nauman. "Most clinicians would say that if you don't have any concussion symptoms you have no problems," said Larry Leverenz, an expert in athletic training and a clinical professor of health and kinesiology. "However, we are finding that there is actually a lot of change, even when you don't have symptoms."

"New research into the effects of repeated head impacts on high school football players has shown changes in brain chemistry and metabolism even in players who have not been diagnosed with concussions and suggest the brain may not fully heal during the offseason."-Emil Venere
"We are finding that the more hits you take the more you change your brain chemistry, the more you change your brain's ability to move blood to the right locations," Nauman said.

'Deviant brain metabolism' found in high school football players. 
http://www.purdue.edu/…/deviant-brain-metabolism-found-in-h…

Biomechanical Correlates of Symptomatic and Asymptomatic Neurophysiological Impairment in High School Football
Evan L. Breedlove, BS1,Thomas M. Talavage, PhD2,3,Meghan Robinson, BS2, Katherine E. Morigaki, MS ATC4,Umit Yoruk, BS3, Larry J. Leverenz, PhD ATC4 , Jeffrey W. Gilger, PhD5, Eric A. Nauman, PhD1,2,6

http://www.ncbi.nlm.nih.gov/pubmed/26786903

Motor control and the immune system

Wow, interesting. Definitely podcast material. If you have been following the literature, recently the immune system and brain function and the gut have been dramatically linked in ways we never knew existed. Now this !

" Princeton University researchers have found that a family of proteins with important roles in the immune system may be responsible for fine-tuning a person’s motor control as they grow, and for their gradual loss of muscle function as they age. The research potentially reveals a biological cause of weakness and instability in older people, as well as a possible future treatment that would target the proteins specifically."

Immune System Proteins Responsible for Fine Tuning and Reducing Motor Control

NEUROSCIENCE NEWSAPRIL 12, 2016

http://neurosciencenews.com/mghi-motor-control-genetics-4035/

Do novice runners really have weak hips and poor running form ?

Folks are ramping up mileage here in Chicago-land for the October marathon. Lots of first timers trying to fill the bucket list, and lots of hip and knee stuff coming into the office. This older article reminded us of the paramount need to slowly build up safe durability. So many folks just follow the ledgers, "This week is 16 miles, 2 more than last sunday, this will keep you on track to get to your taper week". We get all that. But this recipe doesn't work for everyone. Some bodies are so weak and out of shape that their recipe is drastically different than the "average joe or jane". Many need their marathon program time frame doubled so they can build their durability. Yes, novice runners often have functionally unstable/weak hips (amongst other things), and some have bad running form, and many have BOTH ! We remind folks that 26 miles is something to endure for most, and that means preparation, probably preparation before the running training started. So it is about educating them for next time, if there is a next time for them ! Don't forget, running is a sagittal game, one is moving forward. The frontal and axial (rotational) stability is often neglected, and here lies the hole in the bucket that leads to unjuries. Even if you are half way there to your marathon date and doing fine, it is never too soon to start frontal and axial plane durability work, just in case the 18 miler is just beyond what you can endure to protect those joints.

http://www.physiospot.com/research/do-novice-runners-have-weak-hips-and-bad-running-form/

Brace2Play ankle brace. Caveat emptor.

Lets be clear ! This brace is for above the ankle mortise sprains, ie. low and high ankle sprains, sprains to the syndesmosis. It is NOT for ankle mortise and below sprains (ie. lateral and medial stabilzing ankle ligament sprains, ATF, PTF, deltoid ligs etc). If you use this brace on those injuries, good luck......you will not have any protection to those torn ligaments. 
Also, i am hesitant to buy into the "treats shin splints". Braces are supportive, nothing more. So, "supports" shin splints is more accurate IMHO. 
I would also make a case that a syndesmosis sprain (low-high ankle sprain) is not an injury you should be looking for a brace to enable you to continue to play on. Rather, rest and heal and do your initial phase low load rehab. 
Like most things, devices like this have a place and a purpose, but you have to know what you have injury wise, and know what you are dealing with. For example, if you have both a syndesmosis (low-high ankle sprain) AND a deltoid or lateral ligamentous complex sprain, this brace is not what you should chose in our opinion.

https://www.edgemobilitysystem.com/products/brace2play-above-the-joint-ankle-brace?variant=21314299587

Toe grip strength and hallux valgus

#craigpayne over at Podiatry Arena said, "chicken or the egg", which came first ?
Weak Toe Grip Strength (TGS) correlates with hallux valgus . . . 
Do not yet take this study as "do more toe grip strength work", that is NOT what it is saying !!!!!!

We have taken note in our clinics that it "appears" that more long hallux flexor use often "seems" to accentuate a hallux valgus (HV). We continue to study this observation, but not hanging our hat on any conclusions as of yet. But, when someone with HV grips with the long toe flexor hammering down the distal toe, the valgus appears to accentuate. We shall see, its an observation. None the less, we try to get these folks into a pressing, then add the long flexor, and this seems to give adequate purchase on the ground without as much valgus posturing. Keep looking into more active toe extension, separation and hallux abduction as a means to an end. This will likely be a discussion on podcast 113, coming soon. Have you listened to podcasts 108 or 109 yet ? 109 launched Saturday. Keep up !

Weak TGS Correlates with Hallux Valgus in 10 12 Year Old Girls: A Cross- Sectional Study

https://www.researchgate.net/publication/304271421_Weak_TGS_Correlates_with_Hallux_Valgus_in_10_12_Year_Old_Girls_A_Cross-_Sectional_Study

Arm swing and hip ranges.

Most folks think they know a sufficient amount about arm swing, but the truth speaks otherwise for many. Many know heaps about upper quarter biomechanics and how to assess and evaluate the joints of the upper quarter but they have no clue what to look for when it comes to the client using the limb in locomotion. What really happens during the complex arm motions during gait and various forms of locomotion in runners and throwing sports ?
"For the first time, we provide evidence that the spinal interneuronal networks linking the forelimbs and hind limbs are amenable to a rehabilitation training paradigm. Identification of this phenomenon provides a strong rationale for proceeding toward preclinical studies for determining whether training paradigms involving upper arm training in concert with lower extremity training can enhance locomotor recovery after neurological damage.” -Shah et at, Brain 2013 Nov

"Our results demonstrate that altered hip rotational range of motion, measured clinically, has a direct effect on the amount of external rotation torque and horizontal adduction range of motion of the shoulder during the throwing motion." -Laundner et al, (article below)

Want to dive deeply into arm swing ? Want to really know what you are doing and missing ? Goto our blog (thegaitguys.tumblr.com) and in the search box type "arm swing". You will find nothing short of dozens of articles we have written on the topic.

The relationship between clinically measured hip rotational motion and shoulder biomechanics during the pitching motion

Kevin Laudner, Regan Wong, Takashi Onuki, Robert Lynall, Keith Meister

http://www.jsams.org/article/S1440-2440(14)00137-6/abstract

The Skill of walking

The Skill of Walking:
We enjoy most of what goes up on #BreakingMuscle. This one brings up a point we use in the clinic all the time, Mimicry.
We use to to help our patients "see" what we see them doing in their gait or movements. We mimic what we see in their gait while we explain the "what" and "why" of their dysfunctional gait. 
Sometimes we are so wrong when it comes to understanding exactly what we are doing. Think your posture is good ? Check it next time you walk pasta mirror, it is possible it is not as pristine as you think it is. We have mirrors up all over our clinic so people can see what they look like and what they are doing. We encourage them to check on their posture in the mirrors when they walk down to the treatment rooms (and, it is not just for the patients! !). Mirrors can be a real asset when it comes to feedback. 
Mimicry of our clients movements helps them to understand, in 3 dimensions, in many respects better than 2D video what they are actually doing (we discuss this more in podcast 112 launching in a few weeks). Virtual reality is going to clean up many problems we have teaching in the clinic.

http://breakingmuscle.com/natural-move…/the-skill-of-walking

Short foot exercise death.

Here is an article we wrote 5 months ago. It is worth reviewing in light of the other short foot articles we have shared this week.
" . . . this Short Foot exereise is a pretty prehistoric exercise if you ask me, it needs to be dusted off and updated and retaught correctly"- Dr. Allen

" . . . as we are bearing weight down on the foot the arch should be in a controlled pronatory deformation to shock absorb. There is no time to be reacting off the floor into a short foot, that opportunity moment is lost at contact, actually it really never occurs once the ground is met whether one is in initial rearfoot, midfoot or forefoot strike. The foot has to be prepared at the time of contact with its’ most competent arch, not busy reacting after the fact trying to achieve the competent structure. The value in the short foot is earning competence in its loading ability and learning to control its adaptive eccentric lengthening, this must be possible in both toe extension and toe flexion (ground contact)."

We have much more to say in the blog post...... link provided below.

https://thegaitguys.tumblr.com/post/139486938004/is-the-short-foot-exercise-dead-dr-allen

Slower walking in the elderly and calf strength.

"Conclusions: In older men, walking at preferred speed allows triceps surae muscles to generate force with more favorable shortening velocity and to enhance use of tendinous tissue elasticity compared to walking at young men's preferred speed. The results suggest that older men may prefer slower walking speeds to compensate for decreased plantarflexor strength."

Slower Walking Speed in Older Men Improves Triceps Surae Force Generation Ability.
Stenroth, Lauri; Sipilä, Sarianna; Finni, Taija; Cronin, Neil J.

http://journals.lww.com/acsm-msse/Abstract/publishahead/Slower_Walking_Speed_in_Older_Men_Improves_Triceps.97437.aspx

Obese Feet

Doesn't it just make sense ? It needs to be part of the dialogue with your clients.
"Obese feet differ significantly from those of healthy adults, particularly in width."
And a change in width may mean a change in function, changes in mobility and stability, which may lead to pain and at the very least, accommodation and compensation.

Foot dimensions and morphology in healthy weight, overweight and obese males

Carina Price [correspondence] Press enter key for correspondence information [email] Press enter key to Email the author
, 
Christopher Nester
http://www.clinbiomech.com/article/S0268-0033(16)30101-2/abstract?platform=hootsuite

The Types of Jaywalkers

The jaywalker
The Veerer
The Plodder
The retroactive
The runner
The butters
The swaggerers

We walk amongst them all and it is never more ever-present than when moving amongst the masses in a big city. Especially, when we are in a hurry, do we notice the annoying nature of these people the most. However, the problem is ours, because we are all one of these walking types at some point. Next time you are waking in the big city, amongst the masses take note, instead of annoyance.

" . . . the history of pedestrian nuisances is a long and colorful one. The very term “jaywalker” — after jay, a silly person — was coined on August 3, 1924, in a New York Times editorial about the proliferation of pedestrian menaces."
In “The Confusion of Our Sidewalkers: And the Traffic Problem of the Future in the Erratic Pedestrian,” the original 1924 article by M. B. Levick writes:
"There are the veerers who come up sharply in the wind and give no signal. The runners who dash to a goal and then dash back again without even tagging another “it.” The retroactive, moving crabwise. Those who flee and turn swiftly to victory, making a commonplace of the ruse that gave Joe Choynski his fame in the ring. Left-ends and butters, the people who never met the Marquis of Queensberry and to whom Greco-Roman is more foreign than jiu-jitsu.

As mad as the satellite particles of an atom and amid each group, like a nucleus, a static type. The plodder, trudging through Times Square as o’er the lee and knowing neither near side nor off side. The inferiority complexes whose only sense of power is to make the world walk around them. Children of the cigar store Indians standing stock still, so that a couple passing must say “Bread and butter!” Others who are to movement what the color blind are to light and the swaggerers who in an earlier age would take the wall, but in this present confusion must take wall and gutter and all between to assert their precedence."

Here is the full article on Brainpickings.

The Four types of Jaywalkers. Maria Popova

https://www.brainpickings.org/2013/09/26/jaywalkers-wendy-macnaughton-1924/

PreSchool children and barefoot policies

Preschool children and the possible effects of a barefoot policy while in kindergarden. 
You will see it if you pay enough attention to enough barefoot young children, some kids have not yet dropped the toes to the ground.
-study compared the effects of barefoot policy on children where their toes do not rest on the ground while standing normally
-In conclusion, the ground contact of the toes becomes better for boys in kindergarten with a barefoot policy. The results were inconclusive with regard to girls

The effect of the kindergarten barefoot policy on preschool children’s toes

Shigeki Matsuda, Kosho Kasuga, Tadayuki Hanai, Tomohiro Demura, and Keisuke Komura

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4937549/

Dual tasking, Pokemon, and Cross walks.

Someone has to save the Pokemon Go users. The Gait Guys to the rescue !
With the help of these pavement tiles by design firm Büro North, they created a street tile that alerts phone users when they’re approaching danger. Smart Tactile Paving, a concept that would alert walkers — much like a street light — when they’re nearing traffic with the standard red, yellow, green system (see the article link below for this product and idea).
Someone has figured out how to stop you from texting into the street at a cross walk while you and your kids scoop up Squirtles and other nonsense. Oy Vey. 
You are looking down while on your smart phone and some inventor knew they had to do something to save the world from the Pokemon Go death mark population control device. 
Dual tasking is difficult especially when one task is cognitive and the other is spacial and motor. At some point something has to give, especially if you are on the edge of tapping out the executive function centers in the brain.
Recently in the Journal of Applied Biomechanics, Parr and associated took 30 young able bodied healthy individuals with experience texting on cellular phones. The study used an 11-camera optical motion capture system on a 8m obstacle-free floor.

The study showed a reduction in gait velocity in addition to significant changes in spatial and temporal parameters, notably, step width, while the double support phase of the gait cycle increased. Furthermore, and equally disturbing, toe clearance decreased but luckily step length and cadence decreased.

There is much more to say about this today on the blog. It is Rewind Friday, come get reacquainted with the problems your kids will have playing pokemon go.
-Shawn

https://thegaitguys.tumblr.com/post/104851280879/texting-and-walking-your-gait-will-change-when

http://thenextweb.com/insider/2016/07/28/these-pavement-tiles-could-stop-phone-addicts-from-walking-into-traffic/

Short gastrocnemius ?

What is our mantra when it comes to ankle dorsiflexion/ankle rocker ? "Build anterior strength to achieve posterior length." We have been saying it for years. You MUST have the skill, endurance and strength of the anterior compartment muscles (tib.anterior, peroneus tertius, toe extensors) to even remotely get the posterior compartment (gastrosoleus achilles complex)to offer you reasonable length to get the dorsiflexion. You cannot get the joint range just by mobilizing and stretching the posterior compartment. Sure, you can borrow some range after stretching for a very brief period of time, but we choose to get our clients to earn and own the length. if there is contracture, yes, that is another matter. But, those are very rare cases for the most part. This is why so many have troubles transitioning into a more neutral heel drop (ie. lower) heeled shoe. They have not first achieved the requisite anterior SES (skill, endurance and strength) anteriorly to offer the ankle dorsiflexion range. These folks will often gait forward tibial progression through subtler joint over pronation and rear foot over eversion. Obviously this creates internal limb spin and knee valgus loading risks.

Gastrocnemius Contracture in Patients With and Without Foot Pathology. James R. Jastifer, MD1,2⇑, Jessica Marston, MD2

http://fai.sagepub.com/content/early/2016/07/21/1071100716659749.abstract?platform=hootsuite

Running Economy and joint stiffness

Well, this is possible, but so is the existence of aliens we suppose. But this article MAY have more of a dialogue on the faulty strategies of the long and short flexors and extensors as a combined strategy for gait stability and purchase of the foot on the ground. Postural sway may necessitate a toe clench strategy, for example, which could force a toe hammer strategy and thus more long flexor/short extensor tone of the digit muscles. This in itself could alter MPJ passive stiffness over time and may not correlate with any of the study findings below.

Findings by Hok Sum Man et al:
MPJ passive stiffness in sitting position is highly correlated to leg stiffness in running.
•MPJ passive stiffness in sitting position is moderately correlate to vertical stiffness in running.
•MPJ passive stiffness in either sitting and standing position is not correlated to running efficiency.

http://www.gaitposture.com/article/S0966-6362(16)30123-0/abstract?platform=hootsuite

Achilles tendon properties

All tissues need time to accommodate to loading stresses. Adaptation takes time, the achilles is no different than any other tissues that need adaptive time. But, people think that can drop to a low heel-toe drop shoe and pay no price. Time... some people need more adaptive time....gradually work into it. 
- here, increased achilles cross sectional area and other changes

Achilles tendon properties in minimalist and traditionally shod runners.