Tricks of the trade: Backward walking

image credit: https://pixabay.com/vectors/slide-sliding-falling-stickman-151861/

image credit: https://pixabay.com/vectors/slide-sliding-falling-stickman-151861/

A single event can generate asynchronous sensory cues due to variable encoding, transmission, and processing delays. Robert Peterka talks about this, along with posture compensation and system apportionment when it comes to balance and coordination of the visual, vestibular and proprioceptive systems. We have talked about that here on the blog in the past.

We are often looking for ways to “highlight” pathology and make it more visible in the clinical exam. Having your patient/client walk backwards is one of those tools.

Walking and remaining upright in the gravitational plane requires 3 integrated systems to work in concert with one another: the visual, vestibular and proprioceptive systems. Backwards walking requires a more coordinated effort AND IF there is a “hiccup” or extra demand on the system (the proprioceptive in this case), neurological processing can take a little longer, efforts can be delayed and the end result is a greater compensation is needed; this often makes pathology more evident.

Try having your client walk backwards when you are doing your exam and see what we mean. We think you will be surprised with the results : )

Dr Ivo Waerlop, one of The Gait Guys

Peterka RJStatler KDWrisley DMHorak FB. Postural compensation for unilateral vestibular loss. Front Neurol. 2011 Sep 6;2:57. doi: 10.3389/fneur.2011.00057. eCollection 2011.

temporal Shayman CSSeo JHOh YLewis RFPeterka RJHullar TE.Relationship between vestibular sensitivity and multisensory temporal integration. J Neurophysiol. 2018 Oct 1;120(4):1572-1577. doi: 10.1152/jn.00379.2018. Epub 2018 Jul 18.

Hawkins KABalasubramanian CKVistamehr AConroy CRose DKClark DJFox EJ. Assessment of backward walking unmasks mobility impairments in post-stroke community ambulators. Top Stroke Rehabil. 2019 May 12:1-7. doi: 10.1080/10749357.2019.1609182. [Epub ahead of print]

#backwardwalking #clinicalexam #thegaitguys #gaitpathology #clinicaltricksofthetrade

Pronation anyone? Coupling? Walking Speed? How do they relate?

We have talked many times here on TGG about pronation, supination, overpronation, asymmetrical pronation, and more.

When most people think of pronation, they think of midfoot pronation, or pronation about the subtalar or transverse tarsal joints. Pronation can actually occur about any articulation or bone, but with respect to the foot, we like to think of rearfoot (ie. talo-calcaneal), midfoot (talo-navicular) and forefoot (transverse tarsal). The question is why does this matter?

Pronation, with respect to the foot, is defined as a combination of eversion, abduction and dorsiflexion (see picture attached) which results in flattening of the planter vault encompassing the medial and lateral longitudinal arches. In a normal gait cycle, this begins at initial contact (heel strike) and terminates at midstance, lasting no more than 25% of the gait cycle.

In a perfect biomechanical world, shortly following initial contact with the ground, the calcaneus should evert 4-8 degrees, largely because the body of the calcaneus is lateral to the longitudinal axis of the tibia. This results in plantar flexion, adduction and eversion of the talus on the calcaneus, as it slides anteriorly. At this point, there should be dorsiflexion of the transverse tarsal (calcaneo-cuboid and talo-navicular joints). Due to the tight fit of the ankle mortise and its unique shape, the tibial rotates internally (medially). This translates up the kinetic chain and causes internal rotation of the femur, which causes subsequent nutation of the pelvis and extension of the lumbar spine. This should occur in the lower kinetic chain through the 1st half of stance phase. The sequence should reverse after the midpoint of midstance, causing supination and creating a rigid lever for forward propulsion.

Pronation, along with knee and hip flexion, allow for shock absorption during throughout the 1st half of stance phase. Pronation allows for the calcaneo-cuboid and talo-navicular joint axes to be parallel making the foot into a mobile adaptor so it can contour to irregular surfaces, like our hunter gatherer forefathers used to walk on before we paved the planet. Problems arise when the foot either under pronates (7 degrees valgus results in internal tibial rotation), resulting in poor shock absorption or over pronates (> 8 degrees or remains in pronation for greater than 50% of stance phase).

This paper talks about how foot and ankle pathologies have effects on other articulations in the foot. They looked at stance phase of gait in 14 people without pathology at 3 different walking speeds. they found:

coupling relationships between rear foot inversion and hallux plantar flexion and rear foot eversion with hallux dorsiflexion.... When the rear foot everts (as it does as discussed above) during pronation from initial contact to mid stance , the hallux should be extending AND when the rear foot everts, as it should from mid stance to terminal stance/pre swing, the hallux should be plantar flexing to get the 1st ray down to the ground

medial (internal) rotation of there leg was accompanied by mid foot collapse (read pronation) and lateral (external) rotation with mid foot elevation (read supination).... Because of the shape of the talar dome and shape of the talo calcaneal facet joints, the talus plantar flexes, everts and adducts from initial contact to mid stance, and dorsiflexes, inverts and adducts from mid stance to terminal stance/ pre swing

walking speed significantly influenced these coupling relationships....meaning that the faster we go, the faster these things must happen and the greater degree that the surrounding musculature and associated cortical control mechanisms must act

So, when these relationships are compromised, problems (or more often, compensations) ensue. Think about these relationships and the kinetics and kinematics the next time you are studying someones gait.

Dr Ivo Waerlop, one of The Gait Guys

Dubbeldam R1, Nester C, Nene AV, Hermens HJ, Buurke JH. Kinematic coupling relationships exist between non-adjacent segments of the foot and ankle of healthy subjects.Kinematic coupling relationships exist between non-adjacent segments of the foot and ankle of healthy subjects.Gait Posture. 2013 Feb;37(2):159-64. doi: 10.1016/j.gaitpost.2012.06.033. Epub 2012 Aug 27

cool video on our blog to go with this post:

https://www.thegaitguys.com/thedailyblog/2018/8/7/what-do-you-know-about-pronation-and-supination

#gaitanalysis #thegaitguys #pronation #couplingrelationshipsandgait #pronation

The hip flexors do not cause initial hip flexion.

The hip flexors are not responsible for pulling/flexing the swing leg forward in gait or running. The psoas is a mere swing phase perpetuator, not an initiator.
For about 2 decades we have been saying in our lectures, posts and podcasts that it is the reduction of the obliquity of the pelvis during gait from various other tissues and biomechanical events that causes leg swing, meaning the trail leg is brought forward in swing largely by the abdominal muscle linkage to the pelvis (and other loaded tissues) that is responsible for forward swing of the leg. It is not the hip flexor group that does this hip flexion action. Thus it could be considered foolish to train the hip flexors to be the primary swing drivers. Here is another supporting piece of research.

"These experiments also showed that the trailing leg is brought forward during the swing phase without activity in the flexor muscles about the hip joint. This was verified by the absence of EMG activity in the iliacus muscle measured by intramuscular wire electrodes. Instead the strong ligaments restricting hip joint extension are stretched during the first half of the swing phase thereby storing elastic energy, which is released during the last half of the stance phase and accelerating the leg into the swing phase. This is considered an important energy conserving feature of human walking. "

Dan Med J. 2014 Apr;61(4):B4823.
Contributions to the understanding of gait control.
Simonsen EB1.

https://www.ncbi.nlm.nih.gov/pubmed/24814597?fbclid=IwAR3yZQLb2Z0X1LZSVp2hOFLCt3wefsPt4iWEGveswn7-aGaou5OdDqmj4lA

Adaptations and compensations.

Screen Shot 2018-10-25 at 10.54.01 AM.png

. . . the entire system has to adapt to that deficiency. That means compensation. Now, does adding strength to that asymmetry (compensation) have a consequence. Most likely. Will it lead to injury? That is the question.

We are going to keep pounding sand on this one because we believe this is important.
All too often people are working out and strengthening their systems, and that is good. But, if they are strengthening a system that is asymmetric or strengthening a faulty pattern (clearly, as in too much arch collapse) they are likely overburdening the hierarchical system and a component of the chain of that system.
Now, many are going to argue, and we know who those folks are, they are going to argue that if the movement is not painful, if the posturing of the load is not painful, then it is not a problem. Sure, and that is easy to say, but there is no proof they are right either. And, we are not saying we are stonewalled right either, but we are trying to be logical with what we know and what some of the research says (yes, that fits our bias). But our eyes are open and we hear the arguments from the other side, but those arguments come from a crystal ball in our opinion. Truthfully, no one has that crystal ball and can see into the future to see if one side of this argument has any more "legs" to it.
However, we know that . . .

"Human movement is initiated, controlled and executed in a hierarchical system including the nervous system, muscle and tendon. If a component in the loop loses its integrity, the entire system has to adapt to that deficiency. Achilles tendon, when degenerated, exhibits lower stiffness. This local mechanical deficit may be compensated for by an alteration of motor commands from the CNS. These modulations in motor commands from the CNS may lead to altered activation of the agonist, synergist and antagonist muscles."- Chang and Kulig

So, when we see a pattern of loading that is aberrant, and especially when it is most likely playing into a client's painful presentation, it is an easier sell on the thought-arguments above. We know that the entire system has to adapt to deficiencies. It is how we are synergistically built. We have redundancies build into us that protect us. Compensation is part of the redundancy. So, does adding strength to that asymmetry (compensation) have a consequence? Most likely it does, in our opinion. Why allow an area to undergo more loading than we know it should, (ie. valgus knee loading) even if it is non-painful to a client ? Will it lead to eventual injury or pain? That is the question. But we have picked our side of the story, for now, until proven otherwise, and we work from that side of the line. For now.

"yet" is a powerful looming word.
When adding strength takes someones pain away, it doesn't mean you fixed them. It likely means you helped them adapt and protect and better negotiate the loads. However, it also does not mean that your instruction did not build a layer of initial protective strength that will not have a cost further down the road because it wasn't the right medicine for the problem.
When your cars alignment is off, and it is pulling the car to the right towards the ditch, pulling harder to the left on the steering wheel keeps the alignment aberrancy, and the ditch at bay. But nothing was fixed. You adapted and compensated. The problem is still sitting there. And you will get used to the adapted and compensated pattern of steering wheel pull in time. Until the next thing occurs. Maybe the tire will start to chirp in time, the treads silently wear unevenly, and maybe it will be your left shoulder that chirps at you, and not the car.

The squeaky wheel may get the grease, but the misaligned tire is ignored.

Shawn and Ivo, the gait guys

J Physiol. 2015 Aug 1; 593(Pt 15): 3373–3387.
Published online 2015 Jun 30. doi: 10.1113/JP270220
The neuromechanical adaptations to Achilles tendinosis
Yu-Jen Chang and Kornelia Kulig

#gait, #thegaitguys, #gaitcompensations, #gaitproblems, #compensations, #running, #walking, #genuvalgus, #pronation, #CNS, #synergist

Gait and Climbing: Part 1

Lucid Dreaming is the name of a rock in the Buttermilks of Bishop, California. This is no ordinary rock. It is a V15. Summiting this rock is basically only 3 moves off of 3 holds, from your fingertips. The remainder of the climb is sliced bread. If you can do the 3, you can get to the top. The problem is, only a handful of people in the world can do it. How hard can this be, after all you start sitting down.

Strength, stability, mobility, endurance, skill, experience, movement patterns … . it is all here, today, on The Gait Guys blog.

Author: Dr. Shawn Allen

There are things that other people can do in life that rattle your brain. These are tasks that these individuals make look fairly simple, but in actuality are nearly impossible to the average person. The honest fact is that many of us could do many of these things to a degree if we would dedicate a portion of our day to building the engine to perform these tasks, but the truth is that many of us would rather sit down and be entertained than get up and struggle.

Here on The Gait Guys blog, bipedal and quadrupedal gait has been discussed for over 5 years. Discussions have gone deep into the strange quadrupedal gait of Uner Tan Syndrome and have delved into the critical neurology behind CPG’s (Central Pattern Generators) which are neural networks that produce rhythmic patterned outputs. We have gone on and on about arm swing and how they are coordinated with the legs and opposite limb in a strategic fashion during walking running gaits.

Today I will look briefly at the interconnected arm and leg function in a high functioning human arguably one of the best new hot shots in climbing, Alex Megos. This year the German, as seen in this video link today, managed to summit Lucid Dreaming, a V15 in the Buttermilks of Bishop, California. Hell, you can say that this is just a big boulder, but there are not many V15s in the world like this one. Only a few of the very best in the world have even tried this rock, and you can count even fewer who have reached the summit. So, what does V15 mean to you? “virtually impossible” just about sums it up. Watch the video, this V15 starts from a “sit-start”, many folks wouldn’t even get their butts off the ground to complete the first move, that is how hard this is. Watch the video, if this does not cramp your brain, you perhaps you don’t have one.

Are there possible neurologic differences in climbers such as Megos as compared to other quadruped species? Primarily, there is suspect of an existing shift in the central pattern generators because of the extraordinary demand on pseudo-quadrupedal gait of climbing because of the demand on the upper limbs and their motorneuron pools to mobilize the organism up the mountain. We know these quadrupedal circuits exist. In 2005 Shapiro and Raichien wrote “the present work showed that human QL(quadrupedal locomotion) may spontaneously occur in humans with an unimpaired brain, probably using the ancestral locomotor networks for the diagonal sequence preserved for about the last 400 million years.”

As we all know, the interlimb coordination in climbing and crawling biomechanics shares similar features to other quadrupeds, both primate and non-primate, because of similarities in our central pattern generators (CPG’s). New research has however determined that the spaciotemportal patterns of spinal cord activity that helps to mediate and coordinate arm and leg function both centrally, and on a cord mediated level, significantly differ between the quadruped and bipedal gaits. In correlation to climbers such as Megos however, we need to keep in mind that the quadrupedal demands of a climber (vertical) vastly differ in some respects to those of a non-vertical quadrupedal gait such as in primates, in those with Uner Tan Syndrome and during our “bear crawl” challenges in our gyms. This should be obvious to the observer in the difference in quadrupedal “push-pull” that a climber uses and the center-of-mass (COM) differences. To be more specific, a climber must reduce fall risk by attempting to keep the COM within the 4 limbs while remaining close to the same surface plane as the hands and feet (mountain) while a primate, human or Uner Tan person will choose to “tent up” the pelvis and spine from the surface of contact which narrows the spreading of the 4 contact points. Naturally, this “tenting up” can be reduced, but the exercise becomes infinitely more difficult, to the point that most cannot quadrupedally ambulate more than a very short distance. I will discuss this concept in Part 2 of this series on climbing. If you study childhood development and crawling patterns, you need to be familiar with UTS (search our blog, save yourself the time), the flaws in the neurology behind the "Bird Dog” rehab pattern, and crawling mechanics … and of course, study climbers.

Some research has determined is that in quadrupeds the lower limbs displayed reduced orientation yet increased ranges of kinematic coordination in alternative patterns such as diagonal and lateral coordination. This was clearly different to the typical kinematics that are employed in upright bipedal locomotion. Furthermore, in skilled mountain climbers, these lateral and diagonal patterns are clearly more developed than in study controls largely due to repeated challenges and subsequent adaptive changes to these lateral and diagonal patterns. What this seems to suggest is that there is a different demand and tax on the CPG’s and cord mediated neuromechanics moving from bipedal to quadrupedal locomotion. There seemed to be both advantages and disadvantages to both locomotion styles. Moving towards a more upright bipedal style of locomotion shows an increase in the lower spine (sacral motor pool) activity because of the increased and different demands on the musculature however at the potential cost to losing some of the skills and advantages of the lateral and diagonal quadrupedal skills. Naturally, different CPG reorganization is necessary moving towards bipedalism because of these different weight bearing demands on the lower limbs but also due to the change from weight bearing upper limbs to more mobile upper limbs free to not only optimize the speed of bipedalism but also to enable the function of carrying objects during locomotion.

The take home seems to suggest that gait retraining is necessary as is the development of proper early crawling and progressive quadruped locomotor patterns. Both will tax different motor pools within the spine and thus different central pattern generators (CPG). A orchestration of both seems to possibly offer the highest rewards and thus not only should crawling be a part of rehab and training but so should forward, lateral and diagonal pattern quadrupedal movements, on varying inclines for optimal benefits. Certainly I need to do more work on this topic, the research is out there, but correlating the quad and bipedal is limited. I will keep you posted. Be sure to read my 3 part series on Uner Tan Syndrome, here on The Gait Guys blog. Some of today’s blog is rehash of my older writings, naturally I am setting the stage for “Part 2″ of Climbing.

- Dr. Shawn Allen

References:

Shapiro L. J., Raichien D. A. (2005). Lateral sequence walking in infant papio cynocephalus: implications for the evolution of diagonal sequence walking in primates. Am. J. Phys. Anthropol.126, 205–213 10.1002/ajpa.20049

Scand J Med Sci Sports. 2011 Oct;21(5):688-99. Idiosyncratic control of the center of mass in expert climbers. Zampagni ML , Brigadoi S, Schena F, Tosi P, Ivanenko YP

J Neurophysiol. 2012 Jan;107(1):114-25. Features of hand-foot crawling behavior in human adults. Maclellan MJ, Ivanenko YP, Cappellini G, Sylos Labini F, Lacquaniti F.

Muscle activation and gait: EMG studies that differentiate!

image credit:  Cappellini G ,  Ivanenko YP ,  Poppele RE ,  Lacquaniti F . Motor patterns in human walking and running.  J Neurophysiol.  2006 Jun;95(6):3426-37. Epub 2006 Mar 22.

image credit: Cappellini G, Ivanenko YP, Poppele RE, Lacquaniti F. Motor patterns in human walking and running. J Neurophysiol. 2006 Jun;95(6):3426-37. Epub 2006 Mar 22.

Got Muscle activation? Looking for some EMG data on what fires when in walking vs running gait? The conclusion and point of the study are good, but the EMG data and diagrams are awesome for those of you seeking a greater understanding of what goes on when

“The major difference between walking and running was that one temporal component, occurring during stance, was shifted to an earlier phase in the step cycle during running. These muscle activation differences between gaits did not simply depend on locomotion speed as shown by recordings during each gait over the same range of speeds (5–9 km/h). The results are consistent with an organization of locomotion motor programs having two parts, one that organizes muscle activation during swing and another during stance and the transition to swing. The timing shift between walking and running reflects therefore the difference in the relative duration of the stance phase in the two gaits.”

A great read and FREE FULL TEXT

Dr Ivo, one of The Gait Guys

Cappellini G, Ivanenko YP, Poppele RE, Lacquaniti F. Motor patterns in human walking and running. J Neurophysiol. 2006 Jun;95(6):3426-37. Epub 2006 Mar 22. link to free full text: http://jn.physiology.org/content/95/6/3426

#gait, #gaitanalysis, #thegaitguys, #gaitabnormality, #EMGgait, #muscleactivation, #musclerecruitmentpattern

Want to bring out gait pathology? Add something new into the mix...

image source: https://en.wikipedia.org/wiki/Walking

image source: https://en.wikipedia.org/wiki/Walking

We have talked about bringing out compensations and asymmetries in gait patterns by adding a novel stimulus to the exam, like having the client/patient put their hands over their heads, or close their eyes. Here is yet another tool for your toolbox: having the client walk backwards.

Both forward and backward walking share pattern generation control circuits in the brainstem, providing similar (though reversed) kinematic patterns. Backward walking requires different muscle activation sequences which can highlight subtle gait asymmetries, particularly in individuals that have cortical impairment (like the kids with cerebral palsy in this paper) or perhaps people with more subtle cortical impairments, like cerebellar dysafferentation from abnormal joint and muscle mechanoreceptor input and integration. Don’t believe us or what the study says, try it on yourself! It can be a humbling experience : )

In part, the study concludes: “The observed spatiotemporal asymmetry assessments may reflect both impaired supraspinal control and impaired state of the spinal circuitry.”

The next time you are having a difficult time seeing something in an evaluation, or are trying to bring out an asymmetry, in addition to your other tricks, have them walk backwards.

Cappellini G, Sylos-Labini F, MacLellan MJ, Sacco A, Morelli D, Lacquaniti F, Ivanenko Y. Backward walking highlights gait asymmetries in children with cerebral palsy. J Neurophysiol. 2018 Mar 1;119(3):1153-1165. doi: 10.1152/jn.00679.2017. Epub 2017 Dec 20.

Thinking while walking changes arm swing...

Maybe we should keep this in mind while "gait retraining" and "rehabbing". You could be inducing the changes you are seeing on a cortical level. 

This makes you wonder about walking and thinking about sometime else. Being mindful has its advantages, like less cortical laterality and dominance. Remember, in this study, the arm swing is les on the right, so theoretically, less cortical motor drive from the left side. No wonder your gait changes! Be careful which hand you are texting with : )...Better yet, don't walk and text....

Human arm swing looks and feels highly automated, yet it is increasingly apparent that higher centres, including the cortex, are involved in many aspects of locomotor control. The addition of a cognitive task increases arm swing asymmetry during walking, but the characteristics and mechanism of this asymmetry are unclear. We hypothesized that this effect is lateralized and a Stroop word-colour naming task-primarily involving left hemisphere structures-would reduce right arm swing only. We recorded gait in 83 healthy subjects aged 18-80 walking normally on a treadmill and while performing a congruent and incongruent Stroop task. The primary measure of arm swing asymmetry-an index based on both three-dimensional wrist trajectories in which positive values indicate proportionally smaller movements on the right-increased significantly under dual-task conditions in those aged 40-59 and further still in the over-60s, driven by reduced right arm flexion. Right arm swing attenuation appears to be the norm in humans performing a locomotor-cognitive dual-task, confirming a prominent role of the brain in locomotor behaviour. Women under 60 are surprisingly resistant to this effect, revealing unexpected gender differences atop the hierarchical chain of locomotor control.

R Soc Open Sci. 2017 Jan 25;4(1):160993. doi: 10.1098/rsos.160993. eCollection 2017 Jan.
Increasing cognitive load attenuates right arm swing in healthy human walking.
Killeen T1, Easthope CS1, Filli L2, Lőrincz L2, Schrafl-Altermatt M1, Brugger P2, Linnebank M3, Curt A1, Zörner B1, Bolliger M1.

free full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5319362/

Arm swing and instability. To train or not to train... Should we do it?

We have long talked about arm swing and whether to change it, encourage it or just observe it. It appears to be an indicator of potential instability as well as a portent for more dire neurological problems (Alzheimers, Parkinson's)

This study looks at altered arm swing in kids with CP; how it is an indicator that there is a problem and how it can profoundly effect their gait and stability. Cerebral palsy may be an extreme case, but how does it differ REALLY (other than severity) from someone who has a mild neurological impairment, such as movement patterning disorders, that we see each and every day in our friends, family, clients and patients? Try and think out of the box and investigate the implications.

"Observational research suggests that in children with cerebral palsy, the altered arm swing is linked to instability during walking. Therefore, the current study investigates whether children with cerebral palsy use their arms more than typically developing children, to enhance gait stability. Evidence also suggests an influence of walking speed on gait stability. Moreover, previous research highlighted a link between walking speed and arm swing. Hence, the experiment aimed to explore differences between typically developing children and children with cerebral palsy taking into account the combined influence of restricting arm swing and increasing walking speed on gait stability. Spatiotemporal gait characteristics, trunk movement parameters and margins of stability were obtained using three dimensional gait analysis to assess gait stability of 26 children with cerebral palsy and 24 typically developing children. Four walking conditions were evaluated: (i) free arm swing and preferred walking speed; (ii) restricted arm swing and preferred walking speed; (iii) free arm swing and high walking speed; and (iv) restricted arm swing and high walking speed. Double support time and trunk acceleration variability increased more when arm swing was restricted in children with bilateral cerebral palsy compared to typically developing children and children with unilateral cerebral palsy. Trunk sway velocity increased more when walking speed was increased in children with unilateral cerebral palsy compared to children with bilateral cerebral palsy and typically developing children and in children with bilateral cerebral palsy compared to typically developing children. Trunk sway velocity increased more when both arm swing was restricted and walking speed was increased in children with bilateral cerebral palsy compared to typically developing children. It is proposed that facilitating arm swing during gait rehabilitation can improve gait stability and decrease trunk movements in children with cerebral palsy. The current results thereby partly support the suggestion that facilitating arm swing in specific situations possibly enhances safety and reduces the risk of falling in children with cerebral palsy."

Front Hum Neurosci. 2016 Jul 15;10:354. doi: 10.3389/fnhum.2016.00354. eCollection 2016.
Restricted Arm Swing Affects Gait Stability and Increased Walking Speed Alters Trunk Movements in Children with Cerebral Palsy.
Delabastita T, Desloovere K, Meyns P.

link to FREE FULL TEXT: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4945643/

Better gait = better cognition = Better gait

use it or lose it....

"This study demonstrates that cognitive flexibility is associated with walking, in particular under challenging walking conditions, in a cohort of older adults without relevant motor and cognitive deficits. We also demonstrated that older individuals with poor cognitive flexibility use a pattern in variability-related gait parameters across walking conditions that differs from individuals with good cognitive flexibility. This difference might indicate a lower capability of the former population to adapt to challenging walking situations with different demands. Our findings add relevant information to our understanding of gait and balance deficits in older adults with poor cognitive flexibility and may give a basis for interventional studies."

 

FREE full text available here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5442228/

How is your foot is connected to your butt....?

EVD-marcha-075.jpg

If you have been following us for any length of time, you have heard us talk about how the lower kinetic chain is connected, how ankle rocker effects hip extension and how important hallux (great toe) extension is. 

What can we conclude from this study?

toe spreading exercises are important for reducing navicular drop (and thus mid foot pronation, at least statically)
In addition to increased abductor hallucis recruitment in ascending and descending stairs, when hip external rotation exercises were added along with toe spreading exercises folks had more recruitment of the vastus medialis (a closed chain external rotator of the leg and thigh)
 
Keep in mind:

the exercises given were all non weight bearing and open chain for the external rotators. Imagine what might have happened if they were both closed chain AND weight bearing!
They concentrated on the effects of toe spreading (AKA  lift/spread/reach) on the abductor hallucis. It also has far reaching effects on the dorsal interossei, long and short extensors of the toes. 

Abstract: The purpose of the present study was to examine the effects of toe-spread (TS) exercises and hip external rotator strengthening exercises for pronated feet on lower extremity muscle activities during stair-walking. [Subjects and Methods] The participants were 20 healthy adults with no present or previous pain, no past history of surgery on the foot or the ankle, and no foot deformities. Ten subjects performed hip external rotator strengthening exercises and TS exercises and the remaining ten subjects performed only TS exercises five times per week for four weeks. [Results] Less change in navicular drop height occurred in the group that performed hip external rotator exercises than in the group that performed only TS exercises. The group that performed only TS exercises showed increased abductor hallucis muscle activity during both stair-climbing and -descending, and the group that performed hip external rotator exercises showed increased muscle activities of the vastus medialis and abductor hallucis during stair-climbing and increased muscle activity of only the abductor hallucis during stair-descending after exercise. [Conclusion] Stair-walking can be more effectively performed if the hip external rotator muscle is strengthened when TS exercises are performed for the pronated foot.

Goo YM, Kim DY, Kim TH. The effects of hip external rotator exercises and toe-spread exercises on lower extremity muscle activities during stair-walking in subjects with pronated foot. J Phys Ther Sci. 2016 Mar;28(3):816-9. doi: 10.1589/jpts.28.816. Epub 2016 Mar 31. 
link to  FREE FULL TEXT: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4842445/

The over extended knee, genu recurvatum. Watch your kids.

In 2011, in our infancy here at The Gait Guys, we were at the airport. And we saw this . . . .

Screen Shot 2018-02-03 at 12.00.39 PM.png

What do you see here in this young lady ? What you should see here matters. They are just visual things, and lead to visual hypotheses, but it is your job to prove or disprove them. If you like to play these kinds of mental gymnastic games, this is valuable work. This is the work that sets you up to move skillfully, quickly and confidently in the exam and treatment room.
Join us for a rewind, back to 2011.

A young lady with knee recurvatum. Even at the airport you are not safe from The Gait Guys !

Standing waiting for my parents luggage I had to do a double take when i saw this excessive genu recurvatum of the knees. Of course it was much worse in person because of the added dimension that a photo cannot give.  This poor gal probably doesn’t even know she needs us. 

What do we see here and what assumptions can we extrapolate (assumptions from mere standing of course)  ?:

We are going to keep it to things from pelvis down or we will be here all day.

  1. Anterior pelvis tilt. She appears to be sitting back into her pelvis so to speak, doing so we can see an increased lumbar lordosis pressing the pelvis anterior.  Combine this with suspect weak lower abdominals and the pelvis drops in the front. This position is often met with isometric contraction of the gluteals helping to maintain the forward/anterior shifted pelvis.
  2. The above, will create an abnormal (possibly increased) tensile load on the hamstrings since the ischeal tuberosities are being drawn cephalad (up). This can create a net posterior shift of the knee joint since she is in relative hip extennsion.
  3. The knees are likely locked into hyperextension. This will create meniscal tensions and certainly cause increased patellofemoral pressures.  This can also create the rarely diagnosed, but often present, anteriormeniscofemoral impingement syndrome. In this type of presentation the anterior compressive forces are so great compared to what should be balanced forces around the entire joint that the superior leading edge of the anterior mensicus (can affect medial or lateral menisci) begins to become impinged and irritated as the femur rolls and translates too far anterior. You have to know it exists to make the diagnosis.
  4. She will be in relative ankle plantarflexion instead of balancing the tibia neutrally over the talus.  Relative constant plantarflexion means shorter posterior compartment (gastroc-soleus) and usually weak anterior compartment (tibialis anterior and long extensors of toes).  If she is a runner we bet shin splints were on her holiday list of things to resolve. This gal will likely have problems controlling pronation we suspect because of such assumed imbalances.

These are just the sagittal plane flaws we can assume. There are more but this is plenty to think about right now. I was going to walk behind to take a pic so we could make some assumptions about the frontal plane, but people all around were already getting suspicious of me snap photos of so many of them. 

Remember, these are just assumptions from a single static photo. Like in video analysis, anything you pic up on film is just a compensation. It does not tell you what you have wrong until you can test them for neuromuscular integrity and motor pattern assessments.  Do not hang your hat on photos or video analysis. Do the extra work that is required.  After all, you know where ASSUMPTIONS get us.

Oh, and we must not forget to once again thank Mr. UGG boot for helping add another dimension of challenge to this lovely lady ! Although this assumption would be better made off of a frontal plane photo.

Beware of geeks in the airport and shopping malls snapping photos and video. It is likely us, The Gait Guys.

Shawn and Ivo

rewind: https://thegaitguys.tumblr.com/post/14809328401/a-young-lady-with-knee-recurvatum-even-at-the

Conservative Mangement of Parkinsons

Most, if not all of us have either patients, family or friends that have been touched by PD. Here is a video talking about some of the conservative approaches from the literature. We don't talk about gait specifically, but because it is a movement disorder, we felt it appropriate to share.

Do you really need your 5th "pinky" toe ?

This little piggy went to market  . . . . .  as the nursery rhyme goes.

rewind blog post for your enjoyment

Do I Really Need My Pinky Toe?

Just the other day we saw this article in Popular Science written by Sally Zhang.  Sally obviously does not read our blog, but she got a lot of stuff right.

“If you’re born without a pinky toe or have an accident and it’s removed, you can completely do everything you wanted to do,” Dr. Anne Holly Johnson, instructor in orthopaedic surgery at Harvard Medical School, says.

Above you will see a photo of one of the gait guy’s feet.  It is quite clear from the photo that competent use of the pinky toe is not necessary for adequate, and possibly exceptionally skilled, foot function.  Here, check out this video of our foot in these 2 videos (here and here) for some advanced foot function (sans pinky toe). As you can see in the photo above, this 5th toe has likely never felt the ground, this is a fixed deformity.  Flexor and extensor function of the toe are intact, but it does not reach the ground and so assistance in gaining adequate purchase of the 5th metatarsal on the ground is absent. 

This brings us to a deeper question, what about the 5th metatarsal then? Is it necessary ?  Our answer even without deeper research is a solid “yes”. The foot tripod is severely compromised without the 5th metatarsal. The lateral stability of the foot is impaired without the 5th MET.  The natural locking of the calcaneocuboid joint mechanism will be impaired, the peroneal muscles that provide such critical lateral ankle and foot stability will have fascial planes and tendon attachments disengaged, the natural walking gait lateral to medial foot progression would be impaired, propulsion would be impaired and the list goes on and on. And, not even on the local foot/ankle level. Because, if you take out the function and stability of the lateral foot the hip is very likely to suffer lateral (frontal plane) stability deficits. Meaning, the gluteus medius and abdominal obliques will have more difficulty guarding frontal plane drift when in stance phase rendering all of the “cross over gait” risks (link) highly probable.  

So, not much exciting stuff here today. The presence of a functioning pinky toe does not appear to be critical but don’t take away its big brother neighbor, the 5th Metatarsal or trouble is just around the corner. Don’t believe us? Just ask anyone with a non-union fracture (Jones fracture) of the 5th metatarsal.

The answer goes back to the evolutionary history of humans, explains Dr. Anish Kadakia, assistant professor in orthopaedic surgery at Northwestern University. "Primates use their feet to grab, claw, to climb trees, but humans, we don’t need that function anymore,“ Kadakia says. "Clearly we’re not jumping up and down trees and using our feet to grab. We have toes embryologically, evolutionary for that particular reason because we descended from apes, but we don’t need them as people.”

The gait guys, working with 4 toes on each foot, one step ahead of evolution it seems.

Shawn and Ivo,

The gait guys

reference:

http://www.popsci.com/science/article/2013-05/fyi-do-i-really-need-my-pinky-toe?dom=tw&src=SOC



https://thegaitguys.tumblr.com/post/96538178584/do-i-really-need-my-pinky-toe-just-the-other
 

Childhood Long Bone Torsions: Neurodevelopmental Considerations

Key Tag words:  torsions, gait, long bone torsions, femoral torsion, tibial torsion, neuromotor, neuroscience, locomotion, DNS, ambulation, walking, running, gait analysis, infant gait, childhood gait, jiu jitsu, crossover gait, cross over, vestibular, Parkinson's disease

We hit some good topics today, from childhood torsional issues, fix or leave alone ? What to look for when first observing and examining your client's gait plus Balance and vestibular function in gait and bike riding, exercise and neurodegenerative disorders and diseases and even developing proper neuromotor patterns, and inhibiting improper ones.
Plus we hit a favorite topic, the cross over gait and Ivo hits some highlights on gating inhibitory pathways.


Links to find the podcast:

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

Direct Download: http://traffic.libsyn.com/thegaitguys/pod_134_Final.mp3

Permalink URL: http://thegaitguys.libsyn.com/childhood-long-bone-torsions-neurodevelopmental-considerations

Libsyn URL: http://directory.libsyn.com/episode/index/id/6247612


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.

Show Notes:

Walking: The brain leads the body by one step.

Researchers have discovered that we most accurately hit targets when we see them 1 to 1.5 steps ahead of where we were. This is more difficult that it seems because we are making a plan, and at the same time we're making that plan, we're making a movement based on the stuff that we saw a second and half in the past.
Below this link, you will find our post on projecting and estimating steps. Much along the same lines but with a great video to set it up.

https://www.axios.com/when-walking-the-brain-leads-the-body-by-one-step-1513304440-3035f0bb-a992-403f-b084-51e4205cda58.html
https://thegaitguys.tumblr.com/post/44642195883/the-funny-problem-with-the-stairs-at-brooklyns

Gait Recognition

Gait recognition.
Back in university, in my first year, there was a fella on our dorm floor who was basically blind. He could see shapes, light, darkness, figures moving but he could not truly recognize faces until he was about 6 inches from your face. What was amazing though was how quickly he tuned into voice recognition and how we all walked. He could label you from across the room by how you walked it seemed. He had developed a fine tuned sense of movement. I learned something from him by talking to him about this and i use it in my clinic every day when i watch people's gait. Aside from the visual, even the sound of one's foot fall is taken into consideration, there is information there. This is a skill, it comes easily to though who have one of their primary senses, usually visual, blunted. It is about not getting caught up in the details, it is about the quality of the movement of a person that i first glean, then i go back and dissect the details. But, when it comes to the clinical dissection of gait, one has to know all of the time stamp normal gait parameters, the phases, the acts that should occur at each phase, and what should not. If one is a self-labelled gait expert and one cannot spout off the normal phases and what should happen at each phase, and what should not, one should consider down grading their guru label.

"Our brains are especially tuned to see the movements that we and our fellow humans perform and there are particular circuits concerned with perceiving somebody else’s walk, known in the trade as ‘gait’. Studies have shown it is possible to recognise an individual from their walking pattern from any angle. So powerful is the mechanism that even when the walking body is reduced to points of light, carefully placed at the joints of the body, it can still trigger identification, so it may not be the shape or indeed the dress that is the most distinctive feature when it comes to recognising the walker. And we can also reliably infer a person’s emotion from how they walk. "

https://www.theguardian.com/lifeandstyle/2017/may/28/walk-this-way-how-the-brain-recognises-someone-by-their-gait-pippa-middleton

When they walk back. What we are not aware of.


Here is a little something we do, all the time. When the session room is open for the next client, we greet our client in the lobby. We do not have our staff send them back to the room to change and wait for us. We watch them closely. How do they stand up, how do they initiate their gait cycle ? How is their balance? How do they carry their things ?
We ask them to head back to the session room to get changed, while we grab a drink of water. And then, in a sneaky manner, we watch them walk back to the room.
We do this, because, how we walk when we do not think we are being watched, when we are carrying our things (purse, phone, bottle of water, backpack, etc) is how we typically walk. Clients will show all the goodies we need to see: the turned out foot, the hiked shoulder, the limps, the staggers, stumbles, speed, step width, and the like. We also get to see how they move in the shoes they live in, the heeled ones, the broken down ones, the work shoes.

So, when your client is having a formal treadmill gait analysis, what are you seeing? Their best behavior, or the truth ?
There are clues everywhere, and we try to grab all of them, in as natural a manner as possible.
Just some simple thoughts for a Sunday.
Have a great day friends !

Quiz: Walking sideways on a slope

Screen Shot 2018-01-27 at 8.38.15 AM.png

Saturday morning fun Test Q#2:
Arm and leg swing gait quiz. Today we combine concepts from our previous quizes ! This one may really put you to the test.

Two women walking on a sloped beach. They are arm in arm.

Take the principles we have taught you on slope walking, functional leg length differentials to level the pelvis, and arm swing to answer the question.

Here is the question: Are these two more likely to walk “in phase or out of phase”?

* Do not mistaken the question for anti-phasic or phasic. These are two different concepts. If you are out of the loop on these 4 terms, just search the blog for them. Then come back here to answer this brain thumper.

Make for your case in your head and then scroll down to hear my reasoning for my answer.

Link to the answer:  https://thegaitguys.tumblr.com/post/144197829694/arm-and-leg-swing-gait-quiz-today-i-combine
 

Arm and leg swing gait quiz. Today I combine concepts from my previous quizes ! This one may really put you to the test. 

Two women walking on a sloped beach. They are arm in arm.

Take the principles I have taught you on slope walking, functional leg length differentials to level the pelvis, and arm swing to answer the question.

Here is the question: Are these two more likely to walk “in phase or out of phase”? 

* Do not mistaken the question for anti-phasic or phasic. These are two different concepts. If you are out of the loop on these 4 terms, just search the blog for them. Then come back here to answer this brain thumper.

Make for your case in your head and then scroll down to hear my reasoning for my answer.

 

This is an EXTREMELY difficult mind bender of a question. You will need to understand the concepts of 2 prior blog posts to even get to the starting line of the solution.  These are the questions I will often pose to myself so that I force the mental gymnastics of gait biomechanics, and quicken my “gait mind” so that I can leave room for processing unique factors in someone’s individual gait. If you have to take time to process the basics, you are gonna run out of time during a consultation and your client will notice you scratching your head. This is a maturation process, you must put in the work that Ivo and I have, if you want to solve the really tough cases. Simple cases are a break, a vacation if you will, they are welcome during a clinic day, but it is the tough cases that make you stretch that truly fulfill your day.  When you are in the clinic, you have to think fast, efficiently and effectively. Recently I had a powerlifter drive from out of state to see me. His case problems were unresolved for many years.  The treating clinician was on the right page, doing a great job actually, but there were so many issues going on that it was hard to see the root of the problem so the case was just being more “managed” than solved. His case was much like this one, all of the findings and factors were related but because I had seen this hodge podge of complaints before (right foot, right knee, left hip, low back, pelvis distortion and a classic Olympic lift compensation fail) so I knew quickly how to piece it all together into a logical solution and find the single spot to focus the therapy, at the root of the problem. My point is that I had done the hard “head scratching” work long ago, so I readily was able to dismiss the distractors and recognize this beast for what it was.  

Back to the two ladies beach walking, I am basing things on a simple assumption that on most beaches the slope gently levels out at the water line, and that the sand several feet up the beach from the water is on a steeper incline, simple tide erosion principles.  Thus, the woman higher up on the beach will be on a steeper slope, this means more beach side leg knee flexion which means less hip extension, meaning a shorter right step length.  This will impair left arm swing, likely shortening it. Less right hip extension will be met by less left arm extension (posterior arm swing behind the body). This often leads to left arm cross over, arm adduction. 

Here is where things get squirrelly. The lady lower on the beach is on a slightly more gentle slope but her issues are the same just muted slightly. So her right beach side leg is in less flexion at the knee and hip, so hip extension is greater and step length will be longer (relative to her friend higher up on the beach). However, she (ocean side lady) is being led by the impaired arm swing, as discussed above, of the lady on the beach side.  That is, if in fact she is being led or if she is the leader. Oy ! There is the brain bender !  

One must consider who is the more corrupting force. In this case, the more corrupting forces will likely trump out the cleaner forces. The ocean side lady is clearly going to have a “more normal” gait with more normal arm and leg swing and step lengths, quite simply the slope she must negotiate is less so there is less corrupting forces on her. The lady on the beach side is having to accomodate more to her greater slope. The lady up the beach is working harder to keep her pelvis level, her eyes and vestiular apparati on the horizon, her differing step lengths from pulling her off from a straight line course, to keep her from falling over (the steeper the slope, the greater the balance challenge to fight from falling into the beach or falling down the slope. Laws of physics say that things roll down hill, so she is fighting this battle while trying to walk a straight line down a sloped beach, with a friends arm in tow).

So, with all that said, one could logically assume that the gal up the beach is definitely working harder, she has greater differing arm and leg swings from side to side, different step lengths, greater struggles with staying up on the slope when gravity wants her to move down the slope, she has more left arm flexion and adduction to help pair with the struggling and perpetual right hip flexion (and loss of right hip extension), she will have to demonstrate more spinal stiffness to deal with these limb girdle torsional differences side to side and a host of other issues I have outlined in these prior “beach walking” quiz posts. Clearly beach side lady is working harder. Thus, just to maintain her gait posturing up on the slope, she will have to dominate the gait. If she gives in to the signals of her ocean side gal, she will have to soften her slope work strategies and she will move down the slope to easier ground. 

Now, back to the question: Are these two more likely to walk “in phase or out of phase”? 

Who truly knows is the answer ! However, we know beach lady is working harder and must continue to do so to stay up on the slope, so her left arm will remain dominant and the ocean side gal will have to accommodate to a very jerky yet cyclically synchronous gait. To walk linked together they will have to find some rhythm. Walking slower will be easier for them to find a harmoniously rhythm. However, one could make the case that “out of phase” gait will be easier (mental image to help you, if they tie ocean side lady’s right ankle to beach side ladies left ankle you will create “out of phase” gait. Thus, the ocean side lady will not mirror her beach side friend. Thus, when beach lady has right leg in extension, ocean side lady will have her left leg in extension. Why? Well, the left arm swing , their point of union, is the trouble zone. With beach side lady having the left arm in more flexion and adduction, the ocean side lady has to accommodate and meet that troubling arm swing. This means her right leg will be in extension at the same time beach side lady has her left leg in extension. This will be more accommodative work for ocean side lady, but she will just have to go with it. Failure to do so will pull her friend down off the beach and making life harder for her friend.

So there you have it. The person up the slope is working harder to stay here, the person down the slope is working harder to accommodate to a gait that their  lower slope is not requiring. Thus, they are both working hard, but for different reasons. But the winner, the dictator, is the one with the greater slope risk. And thus, she will dictate an “out of phase” gait of her ocean side partner, if they are to still walk embraced. 

How did you do ? Can you make a case for “in phase” as the solution ? I can, but I think that “out of phase” is more likely, for the above reasons.

Thanks for playing  this tough one. Congratulations to you if you followed things smoothly. IF you did not, go back and play the mental game again, I think these are important fundamentals everyone should have if you are doing gait work.

Dr. Shawn Allen

Something you can do NOW to help Parkinsons folks

199px-Sir_William_Richard_Gowers_Parkinson_Disease_sketch_1886.jpg

Anything that can help get more balance and coordination info to the higher centers is a plus for Parkinsons folks, and the texture of the surface they are walking on or the texture of the insole is no different. The more afferent info we can get in through the tactile receptors, joint mechanoreceptors and muscle receptors like the spindles and golgi tendon organs, the better. These all feed (eventually or sometimes directly) to the cerebellum, the king of balance.

In this study they placed little half spheres at the distal phalanx of the hallux, heads of metatarsophalangeal joints and heel. Theses are all areas of increased cortical representation when you look at the sensory homunculus.  They wore them for a week and plantar sensation and stride length both improved, but only the increased plantar sensation remained. Neuroplasticity takes time and we are willing to bet that if they wore them longer, the results would have been more profound.

Sometimes the simplest interventions can go a long way.

 

Lirani-Silva E, Vitorio R, Barbieri FA, et al. Continuous use of textured insole improve plantar sensation and stride length of people with Parkinson disease: A pilot study. Gait Posture 2017;58:495-497. [