Back and Better than ever….

More on the Core. Excerpted from some previously unreleased material which will be available for download soon…

Understanding Neuroreceptors: Movement Concepts

For all you inquiring minds out there, here is a question on one of our YOUTUBE videos we though was worth making into a post.

Question: “Dr Waerlop says that GTO’s (golgi tendon organs) inhibit muscle tension and muscle spindle apparatuses (MSAs) increase muscle tension. But then he says to treat the attachments (GTOs) to increase the tension and the bellies (MSA’s) to decrease. Seems counterintuitive. What is the modality of tx, acupuncture? Massage?…..What is your modailty for treating these? And does that modality inhibit those neurosensors or stimulate them?”

Answer: GTO’s are high threshold receptors that actually modulate muscle activity through inhibition  (Ib afferents) and Spindles are lower threshold receptors receptors that modulate overall activity, particualrly length. Think of the GTO’s as responding to tension and the spindles as responding to muscle length. Spindles are more in the belly of the muscle and GTO’s at the musculo tendonous junctions. By treating the origin and insertion of the muscles, you can modulate both, whereas treating the belly of the muscles, seems to affect the spindles more.

By treating the origin and insertion of the muscles, you can modulate both, whereas treating the belly of the muscles, seems to affect the spindles more.

The modality can be manual or acupuncture stimulation of the origin/ insertion of the muscle that tests weak.We find that acupuncture seems to work bestbut manual methods work just fine as well. We believe we are normalizing function, rather than specifically inhibiting or exciting. Like Chinese medicine, we are balancing the Yin and the Yang, creating homeostasis.

The Gait Guys: Making it real. Making it understandable. Making it happen : )

Doing Squats, Lunges as well as Walking and Running using the Big Toe Ineffectively.

This is an important video.
Here in the initial frames you should see that this fella is using his big toe muscles incorrectly.  There is a long flexor and short flexor of the big toe, just like there is a long and short extensor muscle.
You should clearly see that the big toe sort of curls upwards in the early frames before he is coached to correct in the later frames. In these early frames his medial tripod stabilizing strategy is to use the short toe flexor (FHB – flexor halucis brevis) and more long toe extensor (EHL- extensor hallucis longus). This is what is giving the upward curl presentation. The problem with this strategy is that it is ineffective and uneconomical. It does not help to engage the medial tripod of the foot (ie. keep the big toe knuckle, the metatarsal head, down and purchased well on the ground) nor does it effectively assist the arch posturing of the foot.

You can see at the 17 second mark, with our coaching, he begins to learn and teach himself about the differing uses of the long and short hallux flexors. You can see him over correct from too much short flexor (FHB) into too much long flexor (FHL) where he claws the toe into the ground. You can then see in subsequent frames that he begins to play with the relationship to find a balance between the two. Then, you see that he loses the purchase of the medial tripod at 21 seconds where you see our hand enter the picture and queue the metatarsal head/knuckle down. When done correctly a double arch will form, one in the longitudinal arch of the foot and a second one just under the big toe. This big toe arch should be subtle but visible. If the client collapses this “toe arch” as we call it, they are driving the toe down with abundant short flexor (FHB). This can be easily seen on a pedograph mapping or foot scan represented by too much ink or pressure mapping at the proximal toe and little to no pressure distally through the pad of the big toe. These folks will struggle with adequate anchoring and purchase of the medial tripod (the 1st metatarsal head) and will challenge the longitudinal arch of the foot and thus the tibialis posterior as well as other structures. They can pronate too much and challenge the ankle mortise dorsiflexion range.  Rear foot eversion can become abundant as well. 

Balance of the long and short flexors of the big toe in concert with the long and short extensors. Too much short flexor usually couples with too much long toe extensor (hence the upward curl of the toe as we saw in the early video frames). Too much long flexor couples with too much short extensor, forming a claw-hammer toe presentation. There is a science to this. Balance must be achieved.  Just running barefoot or in minimalism does not guarantee a stronger foot or better form. It may in fact get you a more strength in a bad pattern (as you saw in the first few seconds of the video) which leads to injury  and it may get you stronger into many bad running and walking forms, both at the foot and higher up into your body.

There is more to this game than shoes and random exercises. This is a specific science, if you care to look beyond the basics that allow alot of injuries.  This is how detailed our game is with our athletes and patients, because it is the way the game should be played.

The devil is in the details
Shawn and Ivo………Uber gait geeks.

Some Biomechanical Facts on Oscar Pistorius: 400 m London Olympic Games

Following Saturday’s 400m men’s preliminary heats Jere Longman’s wrote an article in the NYTimes entitled “Pistorius Advances to Semifinals”. In it were some interesting facts. Here is the link to the article. 

Ever since Pistorius’s shut out from the Beijing Olympics scientific and legal debate has continued about whether his prosthetic legs gave him an unfair advantage over sprinters using their natural legs. However, as we all knew, this time around would different in London 2012. Competing on carbon-fiber prosthetics called Cheetahs, Pistorius was going to get his chance and in the process further the debate on what is considered able and disabled.

Prior to Beijing the I.A.A.F. said Pistorius’ carbon-fiber blades violated its ban against springs or wheels that gave an athlete a competitive edge over able bodied athletes. The prosthetic legs allowed him to run as fast as elite sprinters while consuming less energy, the governing body concluded. None the less, the debate has continued over the past few years since Beijing pertaining to where to draw the line between fair play and the right to compete. In 2009 in The Journal of Applied Physiology a study concluded that Pistorius could take his strides more rapidly and with more power than a sprinter on biological legs.

An acquantance of ours who we talk to from time to time, Professor Peter Weyand at SMU Locomotor Performance Laboratory in 2009 looked at Oscar Pistorius-type carbon fiber Cheetah blades a little more closely. In his study (referenced below), in the Journal of Applied Physiology, he conducted three tests of functional similarity between an amputee sprinter and competitive male runners with intact limbs: the metabolic cost of running, sprinting endurance, and running mechanics. What he found was:

  • the mean gross metabolic cost of transport of the amputee sprint subject was only 3.8% lower than mean values for intact-limb elite distance runners and 6.7% lower than for subelite distance runners but 17% lower than for intact-limb 400-m specialists
  • the speeds that the amputee sprinter maintained for six all-out, constant-speed trials to failure were within 2.2 (SD 0.6)% of those predicted for intact-limb sprinters.
  • at sprinting speeds of 8.0, 9.0, and 10.0 m/s, the amputee subject had longer foot-ground contact times ,shorter aerial and swing times and lower stance-averaged vertical forces than intact-limb sprinters [top speeds = 10.8 vs. 10.8 (SD 0.6) m/s].

Weyand concluded that running on modern, lower-limb sprinting prostheses appears to be physiologically similar but mechanically different from running with intact limbs.

Longman’s article listed some of the other facts that have come up in recent years, facts that led to the eventual acceptance of Pistorius in London 2012’s Olympic events.  We have not captured these references specifically (yet, but we will) but in the mean time to keep this blog article timely, lets look at some of the other facts that Longman mentioned in his NYTimes article:

  • While calf muscles generate about 250 percent energy return with each strike of the track, propelling a runner forward, Pistorius’s carbon-fiber blades generate only 80 percent return, Gailey said.
  • Given that Pistorius has no feet or calves, he must generate his power with his hips, working harder than able-bodied athletes who use their ankles, calves and hips, Gailey said.
  • And because the blades are narrow and Pistorius essentially runs on his tip toes, he pops straight up out of the blocks instead of driving forward in a low, aerodynamic position for the first 30 or 35 meters, making him more susceptible to wind resistance, Gailey said.
  • Compared with runners with biological feet, Pistorius also must work harder against centrifugal force in the curves, and his arms and legs tend to begin flailing more in the homestretch, costing him valuable time, Gailey said. His stride is not longer than other runners, as many presume, Gailey said. “It’s not like he’s bouncing high with a giant spring,” Gailey said.
  • The blades “basically allow him to roll over the foot and get a little bounce,” Gailey said, adding: “The human foot operates like a spring, and his feet operate like a spring. But the human foot produces more power than the blades do.”

There is an abundance of interesting information here. We will likely return to some of these topics and facts in the future, but in the meantime we say that everyone has their own demons and deficits. We all have injuries and limitations we have to cope with, in life and in sport. So where the line gets drawn will always be a blurred. This debate on this specific case with Pistorius could go on for years and never reach an agreeable conclusion as to a fair playing field. So, let the games begin and may the best man or woman win, with his or her demons and deficits in tow.  Good work Oscar. Thanks for the inspiration.

Shawn and Ivo, The Gait Guys

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We found 3 other journal articles on Pubmed on Oscar.

  1. Enhancing disabilities: transhumanism under the veil of inclusion? Van Hilvoorde I, Landeweerd L.   Disabil Rehabil. 2010;32(26):2222-7.

  2. Oscar Pistorius, enhancement and post-humans. Camporesi S. J Med Ethics. 2008 Sep;34(9):639.

  3. By designing ‘blades’ for Oscar Pistorius are prosthetists creating an unfair advantage for Pistorius and an uneven playing field? Chockalingam N, Thomas NB, Smith A, Dunning D. Prosthet Orthot Int. 2011 Dec;35(4):482-3.

  4. J Appl Physiol. 2009 Sep;107(3):903-11. Epub 2009 Jun 18.

    The fastest runner on artificial legs: different limbs, similar function?

The nervous system often takes the path of least resistance. Gait compensations are similar. What you are sometimes are seeing is the “least common denominator” with regards to compensation and conservation of energy.  Here is an article that exemplifies this finding.AbstractWhen sharing load among multiple muscles, humans appear to select an optimal pattern of activation that minimizes costs such as the effort or variability of movement. How the nervous system achieves this behavior, however, is unknown. Here we show that contrary to predictions from optimal control theory, habitual muscle activation patterns are surprisingly robust to changes in limb biomechanics. We first developed a method to simulate joint forces in real time from electromyographic recordings of the wrist muscles. When the model was altered to simulate the effects of paralyzing a muscle, the subjects simply increased the recruitment of all muscles to accomplish the task, rather than recruiting only the useful muscles. When the model was altered to make the force output of one muscle unusually noisy, the subjects again persisted in recruiting all muscles rather than eliminating the noisy one. Such habitual coordination patterns were also unaffected by real modifications of biomechanics produced by selectively damaging a muscle without affecting sensory feedback. Subjects naturally use different patterns of muscle contraction to produce the same forces in different pronation-supination postures, but when the simulation was based on a posture different from the actual posture, the recruitment patterns tended to agree with the actual rather than the simulated posture. The results appear inconsistent with computation of motor programs by an optimal controller in the brain. Rather, the brain may learn and recall command programs that result in muscle coordination patterns generated by lower sensorimotor circuitry that are functionally “good-enough.”J Neurosci. 2012 May 23;32(21):7384-91.

Muscle coordination is habitual rather than optimal.

Tight ankles ? Here we do a short little video for mom.

Gain strength in the anterior compartment to achieve posterior compartment length. Stretching calf is not enough when the calf is tight due to increased neurologic protective tone, possibly an attempt to protect the ankle mortise joint.
So, if stretching is not the solution, look to increase facilitation and strength of the weaknesses in the other compartments.  You just might feel the tightness melt away without stretching at all !

Spindle responses and golgi tendon organ responses. The more you know about the nervous system the smarter your treatments will be.

The Gait Guys, using the functioning of the  nervous system to get the responses we want.

 Splay

Watch this video a few times through. Did you catch the subtle abduction moment of the Hallux (big toe) on impact? Did you see the collapse of the transverse metatarsal arch? No?  Watch it until you do.

What gives? We thought toes were supposed to be stable when they hit the ground (and in fact they are).  Read on…

Think of the adductor hallucis. It has 2 heads. The oblique head arises from the proximal shafts of metatarsals 2-4 and inserts on the MEDIAL aspect of the proximal phalynx of the hallux (along with medial fibers of the flexor hallucis brevis); the transverse head arises from the metatarsophalangeal ligaments of  digits 3-5, and the transverse metatarsal ligament and inserts blending with the oblique head on the proximal phalynx of the hallux.

The action of the adductor hallucis mirrors that of the abductor hallucis (which inserts on the LATERAL side of the proximal phalynx. Together, they act to keep the hallux straight and provide a compressive force which stabilizes the big toe WHEN IT IS ON THE GROUND.

The problem here, is that the base of the Hallux is NOT anchored to the ground. This person has a faulty tripod (most likely an uncompensated forefoot varus) and cannot anchor the big toe, there fore the adductor cannot do it’s job. Is is weak (from lack of use) and we see the result: an abducting big toe AND collapse of the transverse metatarsal arch (which the transverse head of the adductor, under normal conditions maintains).

Looks like this guy needs some exercises to descend the head of the 1st metatarsal and make an adequate tripod. Flexing the distal phalynx of the hallux while extending the metatarsophalangeal joint would be a good start. (see Dr Allen demonstrate this here: http://www.youtube.com/user/TheGaitGuys?feature=grec_index#p/u/11/TyRE9dReVTE )

The Gait Guys…promoting foot literacy here and everywhere.