Kidney injury & Running

For all you distance athletes who think you are invincible . . .

"The researchers collected and analyzed blood and urine samples from runners in the 2015 Hartford Marathon. Eight-two (82%) percent of the participants displayed Stage 1 Acute Kidney Injury or AKI. That means kidneys aren't properly filtering waste from blood. It can, in turn, affect other organs like the brain, heart and lung, according to the National Kidney Foundation.

"The kidney responds to the physical stress of marathon running as if it's injured, in a way that's similar to what happens in hospitalized patients when the kidney is affected by medical and surgical complications," Dr. Chirag Parikh, the study's lead researcher, said in a Yale news release. "

article: http://www.ajkd.org/article/S0272-6386(17)30536-X/fulltext

http://www.newsweek.com/running-bad-you-marathons-damage-kidneys-runners-bodies-575829

Running and Life Expectancy

Can running 2 hours a week, generate an increase in life expectancy of 3.2 years, for a net gain of about 2.8 years.? This study suggests so.

"Cumulatively, the data indicated that running, whatever someone’s pace or mileage, dropped a person’s risk of premature death by almost 40 percent, a benefit that held true even when the researchers controlled for smoking, drinking and a history of health problems such as hypertension or obesity.

Using those numbers, the scientists then determined that if every non-runner who had been part of the reviewed studies took up the sport, there would have been 16 percent fewer deaths over all, and 25 percent fewer fatal heart attacks. (One caveat: the participants in those studies were mostly white and middle class.)

https://www.nytimes.com/2017/04/12/well/move/an-hour-of-running-may-add-seven-hours-to-your-life.html?_r=0

Arterial blood flow of the lateral thigh increased significantly after foam rolling exercises compared with baseline

Arterial blood flow of the lateral thigh increased significantly after foam rolling exercises compared with baseline"

There are those in the camp that foam rolling is a waste of time, and those who swear by these various methods of self-soft tissue work. We are in the camp that it is helpful, but more so, if it seems to work for you then do it often. There have been journal articles in the last year that deep soft tissue within an hour of an aggressive workout helps recovery, which supports our camp. This is just one more piece supporting that "doing something" is better than a sofa, beer and Doritos.

Acute Effects of Lateral Thigh Foam Rolling on Arterial Tissue Perfusion Determined by Spectral Doppler and Power Doppler Ultrasound
Hotfiel, Thilo; Swoboda, Bernd; Krinner, Sebastian; Grim, Casper; Engelhardt, Martin; Uder, Michael; Heiss, Rafael U.
The Journal of Strength & Conditioning Research: April 2017 - Volume 31 - Issue 4 - p 893–900

FAI: ankle instability. Proprioceptive issues

We have been saying this over and over, sorry for the repeated nature of this concept. But ankle sprains should not be taken lightly. This study showed:
"Conclusions: Individuals with unilateral FAI had increased error ipsilaterally (injured limb) for inversion movement detection (kinesthesia) and evertor force sense and increased error contralaterally (uninjured limb) for evertor force sense."

No only do they have loss of kinesthesia on the injured side, but this presents along with a reduced evertor force sense as well as contralateral processing deficits. The Brain is paying close attention to the first things that hits the ground, and noting how stable/unstable it is.
Ankle sprains cannot be taken lightly, even the mild ones. Plus, do not forget about the corruption of the frontal plane at the hip that often occurs after these events.

Bilateral Proprioceptive Evaluation in Individuals With Unilateral Chronic Ankle Instability

Andreia S. P. Sousa, PhD; João Leite, BSc; Bianca Costa, BSc; Rubim Santos, PhD

Escola Superior de Saúde do Porto, Centro de Estudos de Movimento e Actividade Humana, Instituto Politécnico do Porto, Portugal

Andreia S. P. Sousa, João Leite, Bianca Costa, and Rubim Santos (2017) Bilateral Proprioceptive Evaluation in Individuals With Unilateral Chronic Ankle Instability. Journal of Athletic Training: April 2017, Vol. 52, No. 4, pp. 360-367.

Extension Thrust Gait /Varus Thrust Gait

Getting inside Dr. Allen's head again:

Last night i was asked to watch a client's gait and assist in the case. It was clear what we were seeing what initially was an "extension thrust gait" (note: i did not video the case, the video posted here is not the client but depicts an extension thrust well). The client had gradually also developed a Varus Thrust gait, which I have written about here several times in the last 2 months. The extension exaggeration often goes with the Varus Thrust gait. The do not have to be paired, but it is easier to go into Varus at the knee if one hyperextends first. Go ahead, stand and lock one knee back and feel the tendencies to move into varus slightly. Valgus is not likely in most people unless some predisposing OA welcomes it.
My point here today, is 2 fold.
These abnormal thrust variants are subtle at the start. To be the best you can be to your client, you have to find these problems in their infancy before they become enormous joint ranges that are impossible to correct, not to mention their soft tissue, ligament, and cartilaginous derangement and maceration. In the case I saw last night we added a sole lift to the entire foot-shoe.
Why? because a client that hyperextends also eats up some of the leg length by folding the knee posteriorly. This, when combining the extension thrust, and in their case, the varus thrust as well, it causes an Anterior Pelvis dumping on that same side, this facilitates further quad loading and thus further extension knee joint drive. It is a viscous cycle. See it in the video here, there seems no way out. The knee load is retrograde. This all creates a functional short leg, furthering the viscous loop. One has to bring the ground up to the shorter leg so help them "feel" the longer leg, thus helping them find the glute to help reorient the pelvis more posterior-ward, gait more finesse of the extensor mechanism (quads mostly). Then we added some kinesio-Rock tape to the posterior knee, applying it in relative knee flexion so that there was some biofeedback as to when they were exceeding knee neutral, moving too far into extension. This sensory motor relearning is critical, without it, they will be dependent upon devices. But the time the client left, with these in hand (foot :) : 2mm sole lift, awareness of aberrant knee extension strategy and varus thrust, how to co-contract the adductors to minimize the varus thrust and a neutral pelvis posture using more glutes (to also help them engage the adductors off the new neutral pelvis), and some flexible biofeedback tape application . . . . the client left with zero extension and varus thrust........and much work to do moving forward.
You have to see these things in their infancy, and that means you have to first recognize them, know how to negotiate around the numerous complicating components of all of them, and not train them deeper into it first of all. Recognize, restore, retrain.
Ala Neil Degrasse tyson: "facts, knowledge, wisdom, insight", . . . in that order.
PS: Oh, the client also had a deeply embedded scoliosis that i had to juggle (there were 5-6 balls going here at once) that was further driving the anterior pelvis drop on the affected side into a torsional pelvis distortion pattern. But, I didn't bring that up, and what i did with that component, because i didn't want anyone brain-barfing on their computer screen. Maybe another day :)

-Dr. Allen

https://www.youtube.com/watch?v=YjRoLtP1di0

Don't let them fool you. Thoughts on gait analysis programs, force plates etc.

Accuracy of gait analysis programs and software.
This is not meant, by any means, to be an exhaustive or comprehensive review of gait analysis programs or software. To be truthful, we here at TGG have abandoned all of the software programs well over a decade ago, programs that we initially used to help us slow the gait down, measure joint angles and other seemingly valuable parameters. As time ticked on, we realized that we had trained our eyes to see most of what the software was telling us, and we also began to value the third visual dimension that these types of programs were thin on. Then came ipads and iphones and the ability with a mere finger to slow down someones gait, reverse it and play forward again. This was all we needed, and this next statement is key, for what we do for our clients.

We were pleased to see the repeatability and consistency in the data and results as outlined in these 2 selected studies. If someones gait problem is repeating, and the software is consistent, the data should be repeatable. But, here it comes, what you see in someones gait is not their problem, it is their habitual pattern of possible dysfunction. There, we said it again, for the 1000th time. Software has limited value in fixing someones problems, it merely presents data points to quantify the gait they present with. And if the client has pain, the software consistently shows the gait pattern that presents with their problem. Changing their gait does not mean you have remedied their problem, you may have, but you are more likely to have asked them to generate a new compensation around a problematic gait. A compensation around a compensation if you will.

Force plates, pedographs, and the like also fall into this data capture category. These are all tools, tools for gathering information that must be folded into hands-on clinical examination information. One needs all of the pieces if they are to play this game right, using just some of them and negating others is abusing the value of each piece data. And, the result of implementing corrective change without all the pieces is gambling that you have enough data to do it right. So, when did this become a game of gambling ?

Gait Posture. 2016 Jul;48:194-201. doi: 10.1016/j.gaitpost.2016.05.014. Epub 2016 May 25. Accuracy and repeatability of two methods of gait analysis - GaitRite™ und Mobility Lab™ - in subjects with cerebellar ataxia.
Schmitz-Hübsch T1, Brandt AU2, Pfueller C3, Zange L3, Seidel A3, Kühn AA4, Paul F4, Minnerop M5, Doss S3.

Biomed Res Int. 2014; 2014: 348659.
Published online 2014 Feb 20. doi: 10.1155/2014/348659
PMCID: PMC3950554. Accuracy and Repeatability of the Gait Analysis by the WalkinSense System.
Marcelo P. de Castro, 1 , 2 , 3 ,* Marco Meucci, 4 Denise P. Soares, 1 , 3 Pedro Fonseca, 3 Márcio Borgonovo-Santos, 1 ,3 Filipa Sousa, 1 , 3 Leandro Machado, 1 , 3 and João Paulo Vilas-Boas 1 , 3

Hip control, the glutes and centration.

Here at GG we have many mantras. One we have been sharing for 10 years or more is
"when the foot is on the ground, the glutes had better be in charge, and when the foot is in the air, the abdominals better be in charge".
We discuss at length with our athletes, and even non-athletes, that if you do not have sufficient control of the hip-pelvis interface (enough skilled stability of the hip into the pelvis, and of the pelvis onto the hip) and as well, sufficient control of the pelvis-spine interface, problems and injuries are a near forgone conclusion.

Here is another article to substantiate this concept, this one from a preventative perspective. Nothing new or earth shaking for most of you here, but always a good reminder, for newbies and the grey haired alike here at the GG brethren.

"Muscle activity of the core unit during explosive running appeared to be associated with hamstring injury occurrence in male soccer players. Higher amounts of gluteal and trunk muscle activity during the airborne phases of sprinting were associated with a lower risk of hamstring injuries during follow-up. Hence, the present results provide a basis for improved, evidence-based rehabilitation and prevention, particularly focusing on increasing neuromuscular control of the gluteal and trunk muscles during sport-specific activities (eg, sprint drills, agility drills)."

Proximal Neuromuscular Control Protects Against Hamstring Injuries in Male Soccer Players: A Prospective Study With Electromyography Time-Series Analysis During Maximal Sprinting.

Schuermans J, et al. Am J Sports Med. 2017.

Treatment of internal rotation gait due to gluteus medius and minimus overactivity

Having enough stable internal hip rotation is just as important as having enough external rotation. Lack of sufficient internal rotation is a real problem during gait and in athletes. This deficit can wreak havoc on the entire kinetic chain. What doesn't occur or what doesn't get buffered in the hips plays out in the knee or in the pelvis.
Don't forget that there are many important internal hip rotators that need your clinical eye on assessment: the vastus lateralis, anterior bundle of the g.medius and g.minimus, TFL to name a few. If you have difficulties visualizing how these muscles drive internal rotation you are not looking at the model from the foot fixated on the ground, you are still seeing things from an open kinetic chain perspective. Just remember, it is even more complicated than that, we are constantly moving through cycles of stability and mobility, with all muscles crossing a joint providing cylindrical give and take (concentric-iso-eccentrical) mobility while at the same time providing adequate stability control through safe joint centration. It is a symphony of events.

Here today, these thoughts were triggered when we came across an old (1998) article on components driving internal rotation in cerebral palsy. In this case, driving too much rotation.

Treatment of internal rotation gait due to gluteus medius and minimus overactivity in cerebral palsy: anatomical rationale of a new surgical procedure and preliminary results in twelve hips.

Joseph B. Clin Anat. 1998. Treatment of internal rotation gait due to gluteus medius and minimus over-activity in cerebral palsy: anatomical rationale of a new surgical procedure and preliminary results in twelve hips.

https://www.ncbi.nlm.nih.gov/m/pubmed/9445093/?i=71&from=gluteal%20weakness

Not moving.

Not moving: the fundamental but neglected motor function.

Have you ever had a client tell you that prolonged standing is their biggest challenge ? "My feet kill me when I have to just stand in a booth at a trade show !" , or "My low back kills me when I stand for 2 hours at a cocktail party". In many of these cases, if they start to move, they feel better. I have plenty of trade show folks complaint of foot pain from the sustained standing. The muscles are under a constant sustained load, there is little to no joint movement, the ligamentous support systems undergo creep, and other things. So, i have them walk back and forth the 5-6 steps within the confines of their trade show booth. Movement is medicine. Sustaining a postural position and thus a fixed joint position over time, even with modest load, is fatiguing and eventually leads to multi-tissue failure. Sustained loading, even when suboptimal, is a problem. The nervous system becomes cranky too as discussed in the abstract below.

Here is an interesting article we are trying to get our hands on (please share if you have access to it). It is not a strong correlation to the discussion above, but there is some conceptual spill over we hope to dive deeper into, perhaps on an upcoming podcast.

Abstract

"The function of the motor system in preventing rather than initiating movement is often overlooked. Not only are its highest levels predominantly, and tonicaly, inhibitory, but in general behavior it is often intermittent, characterized by relatively short periods of activity separated by longer periods of stillness: for most of the time we are not moving, but stationary. Furthermore, these periods of immobility are not a matter of inhibition and relaxation, but require us to expend almost as much energy as when we move, and they make just as many demands on the central nervous system in controlling their performance. The mechanisms that stop movement and maintain immobility have been a greatly neglected area of the study of the brain. This paper introduces the topics to be examined in this special issue of Philosophical Transactions, discussing the various types of stopping and stillness, the problems that they impose on the motor system, the kinds of neural mechanism that underlie them and how they can go wrong.This article is part of the themed issue 'Movement suppression:brain mechanisms for stopping and stillness'."

Philos Trans R Soc Lond B Biol Sci. 2017 Apr 19;372(1718). pii: 20160190. doi: 10.1098/rstb.2016.0190.

Not moving: the fundamental but neglected motor function.
Noorani I1, Carpenter RH2.

Simulated knee flexion contracture to elucidate knee-spine syndrome

When we have on one side either a:
- fixed knee flexion deficit
- weak quadriceps mechanism
- short quadriceps-hip flexor complex with anterior pelvis predominance

. . . these often present functionally as a short leg on that side. Perhaps better put, these will cause a premature forefoot loading response. This loading response will expedite ankle rocker during the stance phase of gait. This will often result in an overactive calf muscle complex and thus shortness over time, further blunting the ankle rocker during tibial progression over the ankle.
Furthermore, there will be a heavy lurching loading response on that same leg, it will surely look like a short leg, functionally. This is why it is imperative to check for full knee extension, ability to engage the quads with endurance and strength in full extension, and be able to connect that anterior chain with the lower abdominals and hip flexors without dumping into an anterior pelvis posture.
The loads move. They move up and down. There are many other causes of this descriptive mechanical chain problem above. Even a weak anterior shin compartment will cause many of these abrupt forefoot loading responses (that can also functionally resemble a knee flexion contracture) and promote early and excessive knee flexion during early limb loading response, when we rather should be posturing over a more stable and extended knee. They feed off of each other. It is why these syndromes of problems get intermixed and complicated to both diagnose and remedy.

PS: we chose this photo for a reason today, because high heels make us load the forefoot prematurely during the gait cycle, and we have to dampen the loads with the quadriceps.

Take what you will from this study, but it is really the global picture it suggests. That being, everything can affect everything.
PS: we hate the name they put on this study at the end. . . . "Knee-spine syndrome". For what its worth.

"However, the 30 degrees (simulated knee) contracture significantly changed the kinematics in each of the following planes. In the coronal plane, the trunk tilted to the contracture side in standing and walking. In the sagittal plane, posterior inclination of the pelvis in standing significantly increased. In addition, anterior inclination of the trunk and pelvis during walking significantly increased. In the axial plane, trunk rotation to the unaffected side significantly decreased during walking. The vertical knee force in the contracture limb decreased, being accompanied by the increase of the force in the unaffected limb during standing and walking. Results of our study suggest that knee flexion contracture significantly influences three-dimensional trunk kinematics during relaxed standing and level walking, and will lead to spinal imbalance. These facts may explain the onset of the "Knee-Spine Syndrome".

Gait Posture. 2008 Nov;28(4):687-92. doi: 10.1016/j.gaitpost.2008.05.008. Epub 2008 Jun 26.

A gait analysis of simulated knee flexion contracture to elucidate knee-spine syndrome.

Harato K1, Nagura T, Matsumoto H, Otani T, Toyama Y, Suda Y.

Video Gait Case

Video Case: Another 2 minutes of chatter inside Dr. Allen's brain.
Great case, idiopathic toe walker since childhood, WITH CORRECTION.

What is amazing here is how "soft wired" this pattern is in this case. Usually toe walking is quite hardwired ("search" our blog for Primitive Toe walking) and very difficult to change if one is even extremely lucky. This case was very malleable and immediately changed by conscious effort, with zero queuing. In this case, the mere verbal queue "scuff some imaginary mud off your heels" drove him into ankle dorsiflexion and ankle rocker patterning.
Cases are sometimes about finding out if the client has the working parts, biomechanically, and the neurologic awareness and wiring to even implement a different pattern. This is a classic case of, "we do what we do"; we can get used to, and accustomed to, anything especially if there is no consequence. We can learn any habit, right or wrong. That is the beauty of the nervous system; it will learn anything you teach it, right or wrong. It is also why we worry so much. Why worry you ask ? Because everyday on this earth, some trainer, doctor, therapist, coach etc is telling their client to change they way they are doing something, whether that is "take a longer stride" or"swing the right arm more" or, "turn the left foot in more". The brain will adapt. The question is, are you fixing your client, or just asking them to compensate around their compensation, rather than fixing the underlying rooted problem ? This requires "facts, knowledge, wisdom and then insight", in that order (thanks #neiltyson).
Great case, a "Soft wired" toe walker, with immediate change in seconds. He had all the mechanical parts and neurologic wiring and ability to adapt to another locomotor pattern. Sometimes all we need to know is how to do something the right way, if you have the working parts and neurology to do so.

Video gait case

* VIDEO case: If you had a front row seat inside Dr. Allen's head during a day in the clinic (and admittedly outside the clinic as well), this is the kind of mental chatter you would hear. It goes on all day, it never stops :( Oy ! The chatter . . . . Make, It, Go, Away !

Central Pattern Generators (CPGs) and gait / locomotion. Do the arms and legs talk to eachother ?

On the topic of central pattern generators (CPGs) and gait / locomotion

"If quadrupedal coordination is deeply embedded in the human nervous system then one might expect this to be revealed in conditions when there is a conflict between voluntary arm movements and walking. For example, Muzii et al. [44] combined a walking and a clapping task at preferred rates. Hand clapping was found to be tightly coupled to heel strike. When instructed to walk and clap at different rates (e.g. walk normally but clap faster) the subjects were not able to perform this task, implying that the walking rhythm dominated the coordination. Hence coupling is fairly robust, a finding that was confirmed by the observation that the typical 1:1 diagonal coordination during gait is maintained even when either one of the limbs involved is loaded with an extra 2 kg." - P. Meyns et al. / Gait & Posture 38 (2013) 555–562

We have discussed this same thing during our "dual tasking" blog posts. These things can be learned and modified with attentive training, but is it strongly suggested that the underlying CPG patterns are fairly robust.  This is not to say that leg swing is the king, that it runs the show, but it seems dominant. And as the Meyns paper reviews, there is an influence from the upper limbs in terms of enhancing and shaping the overall movement and coordination of all 4 limbs.

And as the Meyns paper states, "although the connections go both ways, it is clear in the to date animal models studied, that "the caudorostral connections seem to be the most powerful ones." Meaning, the pelvis and lower limb motor patterns and pattern generators seem to dominate over the upper limbs and upper pattern generator centers.
"The dominance of the lumbosacral girdle over the cervicothoracic is probably preserved in humans as well. For example, Sakamoto et al. [65] showed that during combined arm and leg cycling, the cadence of the arms was significantly altered when leg cycling cadence was changed. The opposite, however, was not true, i.e. the arms did not affect the leg cadence." Meyns et al.

And, "the authors concluded that ‘‘the neural signal induced by the upper limb movements contributes not merely to enhance, but to shape the lower limb locomotive motor output, possibly through interlimb neural pathways’’.-Myens et al.

The how and why of arm swing during human walking
Pieter Meyns a,1, Sjoerd M. Bruijn a,b,1, Jacques Duysens a,c,*
P. Meyns et al. / Gait & Posture 38 (2013) 555–562

Pod 133: Two Gait Cases & their Gait Rehab

Today we discuss a few cases we have seen.  We discuss 2 cases, both involved poorly adapted gaits from injury, adaptations that had become the client's new norm. Once you get past Ivo's case presentation, which is very in depth, the discussions quickly go into very important topics that we all over look, namely gait and gait rehab, gait thresholds, metabolic thresholds, cortical fatigue, and how to use some neurologic principles to restore a problematic gait.

Key Tag words:
gait, concussion, head trauma, cortical fatigue, endurance, strength, gait analysis, gait problems, gait rehab, running, running injuries, run-walk, SCFE, slipped epiphysis, femoral growth plate, hip stress fractures, growth plate injury, hip dysplasia, limping gait, club foot, step length, stride length

Links to find the podcast:

iTunes page: https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138?mt=2

http://traffic.libsyn.com/thegaitguys/pod_133final.mp3

http://thegaitguys.libsyn.com/pod-133-two-gait-cases-their-gait-rehab

Libsyn Directory: http://directory.libsyn.com/episode/index/id/6184651

Our Websites:
www.thegaitguys.com

summitchiroandrehab.com doctorallen.co shawnallen.net

Our website is all you need to remember. Everything you want, need and wish for is right there on the site.
Interested in our stuff ? Want to buy some of our lectures or our National Shoe Fit program? Click here (thegaitguys.com or thegaitguys.tumblr.com) and you will come to our websites. In the tabs, you will find tabs for STORE, SEMINARS, BOOK etc. We also lecture every 3rd Wednesday of the month on onlineCE.com. We have an extensive catalogued library of our courses there, you can take them any time for a nominal fee (~$20).

Our podcast is on iTunes and just about every other podcast harbor site, just google "the gait guys podcast", you will find us.

What do you know about the Ia Afferents?

This is a nice study looking at lateral gastroc activity and changing firing patterns with speed of movement. Great if you treat anyone or anything that walks...

Ia afferents

You remember them, large diameter afferent (sensory) fibers coming from muscle spindles and appraising the nervous system of vital information like length and rate of change of length of muscle fibers, so we can be coordinated. They act like volume controls for muscle sensitivity. Turn them up and the muscle becomes more sensitive to ANY input, especially stretch (so they become touchy…maybe like you get if you are hungry and tired and someone asks you to do something); turn them down and they become less or unresponsive.

Their excitability is governed by the sum total (excitatory and inhibitory) of all neurons (like interneuron’s) acting on them (their cell bodies reside in the anterior horn of the spinal cord).

If we slow things down, the rate of change of length slows as well and excitability decreases, like we see in this study (3-6% slower). We also notice that the length of contraction increases; hmmm, why doesn’t it decrease?

Remember these folks are on a treadmill. The treadmill is constantly moving, opposite the direction of travel. With the foot on the ground, this provides a constant rate of change of length of the gastroc/soleus (ie, it is putting it through a slow stretch); so , once the muscle is activated, it contracts for a longer period of time because of the treadmill putting a slow stretch on the gastroc (and soleus).

This article also talks about people with upper motor neuron lesions. An important set of inhibitory neurons come from higher centers of the brain, in the motor cortex. These tend to attenuate the signals affecting the Ia afferents, and keep us stable. When we have an upper motor neuron lesion (like a brain lesion or stroke), we lose this “attenuation” and the stretch reflexes (and muscle tone) becomes much more active (actually hyperactive), making the muscle more sensitive to stretch. This loss of attenuation, along with differing firing patterns of the gastroc are important to remember in gait rehab.

The soleus and medial gastroc begin firing in the first 10% of the gait cycle (at the beginning of loading response) and fire continuously until pre swing (peaking just after midstance). The lateral head begins firing at midstance; both heads (along with soleus) decelerate the forward momentum of the tibia, flex the knee at midstance, and the medial head assists in adducting the calcaneus to assist in supination.

Making sure these muscles fire appropriately is important and needling is just one way of helping them to function better. Don’t overlook the tricep surae on your next patient that has a “hitch in their giddyup”.

Effects of treadmill walking speed on lateral gastrocnemius muscle firing.

by Edward A Clancy, Kevin D Cairns, Patrick O Riley, Melvin Meister, D Casey Kerrigan

American journal of physical medicine rehabilitation Association of Academic Physiatrists (2004) Volume: 83, Issue: 7, Pages: 507-51 PubMed: 15213474

Abstract

OBJECTIVE: To study the electromyographic profile-including ON, OFF, and peak timing locations-of the lateral gastrocnemius muscle over a wide range of walking speeds (0.5-2.1 m/sec) in healthy young adults. DESIGN: We studied gastrocnemius muscle-firing patterns using an electromyographic surface electrode in 15 healthy subjects ambulating on a treadmill at their normal walking speed and at three paced walking speeds (0.5, 1.8, and 2.1 m/sec). Initial heel contact was determined from a force-sensitive switch secured to the skin over the calcaneous. RESULTS: For all speeds, the gastrocnemius firing pattern was characterized by a main peak, occurring 40-45% into the gait cycle, that increased in amplitude with walking speed. Speeds of > or =1.3 m/sec produced a common electromyographic timing profile, when the profile is expressed relative to the stride duration. However, at 0.5 m/sec (a speed typical of individuals with upper-motor neuron lesions), the onset of gastrocnemius firing was significantly delayed by 3-6% of the gait cycle and was prolonged by 8-11% of the gait cycle. CONCLUSION: Many patients with upper motor neuron lesions (e.g., stroke and traumatic brain injury) walk at speeds much slower than those commonly described in the literature for normal gait. At the slow walking speed of 0.5 m/sec, we have measured noticeable changes in the electromyographic timing profile of the gastrocnemius muscle. Given the importance of appropriate plantar flexor firing patterns to maximize walking efficiency, understanding the speed-related changes in gastrocnemius firing patterns may be essential to gait restoration.

The SCM and Gait?

We remember that we have 3 systems that keep us upright in the gravitational plane: The visual system, The vestibular system and the proprioceptive system. As we age, we seem to become more dependent upon the visual system to maintain stability of the head (which is largely under the purview of the vestibular system).  Older folks seem to be less stable than younger ones....At least when it comes to head stability.

This study looked at the neuromechanical mechanisms of head stability in younger and older women during gait initiation, a time when we employ the visual system for things like balance and foot placement. The visual system  in this case is king and trumps the other systems in that it will do whatever it need to to keep the eyes level with the horizon.

They used a  stereophotogrammetric system to measure angular displacement and acceleration and surface emg (no, not the best) to look at activation latencies of neck (particularly the SCM), trunk and pelvic muscles. Older women had higher variability in angular displacement of the head (possibly age related breakdown of the vestibular system?), decreased ability to attenuate accelerations in the saggital (forward) plane, and increased SCM activation latencies.

The bottom line?

Make sure the older women you are working with have:

- better functioning joints
- better functioning muscles (appropriate skill, endurance and strength)
- better proprioception

You could help these by:

- manipulating and mobilizing joints that have pathomechanics
- improving muscular function through endurance and strength based exercises of the neck as well as core
-improving muscular function through modalities you use
-give them more proprioceptive based exercises, especially ones which incorporate the head, like head repositioning exercises,
-encourage them to engage in proprioceptive heavy activities, like rock climbing (which also works the axial extensors), cross country skiing, bike riding, etc

Maslivec A, Bampouras T, Dewhurst S, Vannozzi G, Macaluso A, Laudani L.  Mechanisms of head stability during gait initiation in young and older women: A neuro-mechanical analysis.
J Electromyogr Kinesiol. 2017 Nov 23;38:103-110. doi: 10.1016/j.jelekin.2017.11.010. [Epub ahead of print]

link to free full text: http://www.sciencedirect.com/science/article/pii/S1050641116302036?via%3Dihub

More QP: one way to treat it

You may have seen our last post on the QP. If not, see here. 

 "Thus, the tendon and tendinous slips of the FHL may distribute the load of the great toe to the second toe to the third or fourth toe in the forefoot, especially during toe-off. In addition, the main attachment of the QP to the tendinous slips of the FHL may provide more efficient control of the long flexor tendons in comparison with that of the QP to the tendon of the FDL."(1)

So, in other words, the QP is major player most likely through the attachments of the long flexor of the great toe and its attachment to the other digits, rather than directly effecting the long flexors of the toes. It is acting a "a great equalizer" during the second half of stance phase.  

Abstract:  The aim of this study was to demonstrate the morphology of the quadratus plantae (QP) in relation to the tendinous slips of the flexor hallucis longus (FHL) and their surrounding structures, thereby providing data to understand function of the QP during gait, and for analyzing the movements of the foot and designing postoperative rehabilitation programs. The QP was investigated in 50 specimens of embalmed adult cadavers. The QP inserted into the tendon of the flexor digitorum longus (FDL) and the tendinous slips of the FHL in 96%, and only to the tendon of the FDL in 4%. The tendinous slip of the FHL targeted the tendon for the second toe in 4 of the 50 specimens (8%). The tendinous slip divided into two separate slips to the tendons for the second and third toes in 32 specimens (64%), and for the second, third, and fourth toes in 14 specimens (28%). Thus, the tendon and tendinous slips of the FHL may distribute the load of the great toe to the second toe to the third or fourth toe in the forefoot, especially during toe-off. In addition, the main attachment of the QP to the tendinous slips of the FHL may provide more efficient control of the long flexor tendons in comparison with that of the QP to the tendon of the FDL.

There are many ways to treat the muscle; here is one way.

1) Hur MS1, Kim JH, Woo JS, Choi BY, Kim HJ, Lee KS.An anatomic study of the quadratus plantae in relation to tendinous slips of the flexor hallucis longus for gait analysis. Clin Anat. 2011 Sep;24(6):768-73. doi: 10.1002/ca.21170.

The QP....What's the deal?

Possibly heard of, rarely implicated and not often treated, this is one muscle you should consider taking a look at.

The quadratus plantae is generally considered to arise from two heads of differing and variable  fiber type composition, with the lateral head having slightly more Type 1 endurance fibers (1) The two heads are separated from each other by the long plantar ligament, though it can arise from from one (somewhat more common)  to 3 heads (very rare).  The attachments can be variable, The medial head is larger and more muscular, attached to the medial calcaneus, lateral aspect of the long plantar ligament and often from the plantar calcaneocuboid ligament (2);  the lateral head is smaller and more tendinous, attaching to the lateral border of the inferior surface of the calcaneus and the long plantar ligament.  The two portions join and end in a flattened band which inserts into the lateral, upper and under surfaces of the muscles, tendons or aponeurosis of predominantly the flexor digitorum longus and usually of the second and third, and sometimes fourth toes (2,3). 

Its action can be equally as variable. In addition to augmenting the pull of the long flexor tendons along the long axis of the foot and so that the 3rd and 4th toes do not curl under the foot, the tendinous slips of the FHL may distribute the load of the great toe to the second toe to the third or fourth toe in the forefoot, especially during toe-off (3).

look at the 4th and 5th digits trying to "crawl under the foot"

The main attachment of the QP to the tendinous slips of the FHL may provide more efficient control of the long flexor tendons in comparison with that of the QP to the tendon of the FDL (3). EMG studies suggest it resists extension of the toes during the stance phase of locomotion, which serves to increase the stability of the foot. Additional EMG studies suggest it actually acts as a primary toe flexor in voluntary movements, being preferentially recruited over flexor digitorum longus and from comparative anatomical considerations it also seems likely that quadratus plantae may be an intrinsic evertor of the foot (4).

This muscle is a major player in gait and rehabilitation of this muscle should not be overlooked. I could only find one study looking at exercise activation of the QP (5) . It was examined along with the abductor hallucis, flexor digitorum brevis, abductor digiti minimi, flexor digiti minimi, adductor hallucis oblique, flexor hallucis brevis, interossei and lumbricals during rehabilitative the short-foot exercise, toes spread out, first-toe extension, second- to fifth-toes extension.

So, what else can you do?

• you could ignore the muscle and hope it gets better. (in all likelihood it will worsen)
• you could give them long flexor, toe scrunching towel-curling, marble-grasping exercises, like you see all over the internet…and give the flexor digitorum longus even more of a mechanical advantage, and make the problem worse
• you could give them exercises to increase the function of the long extensors, which would increase the mechanical advantage of the quadratus plantae. like the shuffle walk; lift, spread and reach and tripod standing exercises
• look north of the foot to see what might be causing the problem (loss of ankle rocker, insufficient gluteal activity, loss of internal rotation of the hip, etc) 

Check out the QP on your next foot pain patient, or whenever you see the toes trying to crawl under the foot. You may be surprised at your results. 

1. Schroeder KL, Rosser BW, Kim SY. Fiber type composition of the human quadratus plantae muscle: a comparison of the lateral and medial heads. J Foot Ankle Res. 2014 Dec 13;7(1):54. doi: 10.1186/s13047-014-0054-5. eCollection 2014.

2. Pretterklieber B1. Morphological characteristics and variations of the human quadratus plantae muscle. Ann Anat. 2017 Nov 21;216:9-22. doi: 10.1016/j.aanat.2017.10.006. [Epub ahead of print]

3. Hur MS, Kim JH, Woo JS, Choi BY, Kim HJ, Lee KS. An anatomic study of the quadratus plantae in relation to tendinous slips of the flexor hallucis longus for gait analysis. Clin Anat. 2011 Sep;24(6):768-73. doi: 10.1002/ca.21170.

4. Sooriakumaran P, Sivananthan S. Why does man have a quadratus plantae? A review of its comparative anatomy. Croat Med J. 2005 Feb;46(1):30-5.

5. Gooding TM, Feger MA, Hart JM, Hertel J. ntrinsic Foot Muscle Activation During Specific Exercises: A T2 Time Magnetic Resonance Imaging Study. J Athl Train. 2016 Aug;51(8):644-650. Epub 2016 Oct 3.

image from: http://boneandspine.com/what-is-anteversion-and-retroversion/

Femoral versions and torsions?

While searching for something else, we ran across this post. A pretty good lay discussion and explanation about femoral torsions. Technically, versions are NORMAL variations or limb rotations that are within accepted limits and TORSIONS are pathological, when it measures 2 or greater standard deviations from the mean and is considered pathological. Femoral versions are the angular difference between the transcondylar and transcervical axes. The femur is normally anteverted (1). 

We liked the last section talking about how to compensate for them and "acceptable" work arounds and biomechanics. 

https://b-reddy.org/2013/05/09/talking-about-hip-retroversion/

1. Staehli L in: Fundamentals of Pediatric Orthopedics Lippincott Williams & Wilkins, Jun 15, 2015 p 144

Want to be faster?

Take this simple test. 

If you want to be faster, you had better incorporate some proprioceptive training into your plan. It is the 1st part of our mantra: Skill, Endurance, and Strength (in that order). Proprioceptive training appears to be more important that strength or endurance training from an injury rehabilitation perspective injury rehabilitation perspective as well part of an injury prevention program

 What is proprioception? It is body position awareness; ie: knowing what your limbs are doing without having to look at them.

Take this simple test:

• Stand in a doorway with your shoes off. Keep your arms up at your sides so that you can brace yourself in case you start to fall. Lift your toes slightly so that only your foot tripod remains on the ground (ie the base of the big toe, the base of the little toe and the center of the heel.). Are you able to balance without difficulty? Good, all 3 systems (vision, vestibular and proprioceptive) are go.

• Now close your eyes, taking away vision from the 3 systems that keep us upright in the gravitational plane. Are you able to balance for 30 seconds? If so, your vestibular and proprioceptive systems are intact.

• Now open your eyes and look up at the ceiling. Provided you can balance without falling, now close your eyes. Extending your neck 60 degrees just took out the lateral semicircular canals of the vestibular system (see here for more info). Are you still able to balance for 30 seconds? If so, congrats; your proprioceptive system (the receptors in the joints, ligaments and muscles) is working great. If not, looks like you have some work to do. You can begin with exercises we use every day by clicking here.

Proprioception should be the 1st part of any training and/or rehabilitation program. If you don’t have a good framework to hang the rest of your training on, then you are asking for trouble. 

Timothy E. Hewett, PhD, , Kevin R. Ford, MS, Gregory D. Myer, MS, CSCS Anterior Cruciate Ligament Injuries in Female Athletes: Part 2, A Meta-analysis of Neuromuscular Interventions Aimed at Injury Prevention The American Journal of Sports Medicine Vol 34, Issue 3, pp. 490 - 498   link to free full text: http://journals.sagepub.com/doi/abs/10.1177/0363546505282619

Lephart SM1, Pincivero DM, Giraldo JL, Fu FH. The role of proprioception in the management and rehabilitation of athletic injuries. Am J Sports Med. 1997 Jan-Feb;25(1):130-7.