Surgery vs casting...same results

image source: https://commons.wikimedia.org/wiki/File:Trimalleolar_Ankle_Fracture.jpg

We see many people for all types of fractures and rehab. This study looks at folks who had ankle fractures who either got mhm casted or had surgical management. Looks like conservative is just as good in this case.

"In a pre-specified, 3-year extension of a randomized clinical trial of equivalence, close-contact casting maintained equivalence in function compared to surgery in older adults with unstable ankle fracture. Furthermore, no significant differences were reported in quality of life or pain. The authors concluded that the focus of treatment for these patients should be on obtaining and maintaining reduction until union, using the most conservative means possible.

The study enrolled 461 patients; the control group (n=254) had non-diabetes-related foot complications; the study group (n=207) had diabetic foot pathology (including 61 [32%] with diabetic foot ulcer, Charcot neuropathy, foot infection, or acute neuropathic fractures and dislocations).

Researchers found no significant differences between the 2 groups related to fear of blindness, diabetic foot infection, or kidney failure needing dialysis. When compared to those without diabetic foot problems, the authors found that the 32% of the study group with identified diabetic foot disease were 136% more likely to rate LEA as their greatest fear and that 49% were less likely to rate death as their greatest fear. In their conclusion, the authors noted that the presence of a diabetic foot-related complication, having diabetes for more than 10 years, use of insulin, and having peripheral neuropathy were all variables that subjects associated with identifying LEA as the greatest fear.

Wukich DK, Raspovic KM, Suder NC. Patients with diabetic foot disease fear major lower extremity amputation more than death. Foot Ankle Spec. 2018;11(1):17-21."

source: http://lermagazine.com/issues/may/three-year-follow-up-close-contact-casting-vs-surgery

image source: https://commons.wikimedia.org/wiki/File:Trimalleolar_Ankle_Fracture.jpg

Gait: A bottom up process (mostly).

"Bottom up" process of running ? Support that it is not "top down".

"These results support a passive arm swing hypothesis for upper body movement during human walking and running, in which the trunk and shoulders act primarily as elastic linkages between the pelvis, shoulder girdle and arms, the arms act as passive mass dampers which reduce torso and head rotation, and upper body movement is primarily powered by lower body movement."
"Angular acceleration of the shoulders and arm increased with torsion of the trunk and shoulder, respectively, but angular acceleration of the shoulders was not inversely related to angular acceleration of the pelvis or arm."

At The Gait Guys have been saying this for years in our writing based off of the research we have consumed that coaching changes in arm and shoulder swing and posture is not the way the system works, or the way to go with coaching running, not without possible ramifications to the athlete by overriding how the system is wired for locomotion. The arm motor patterns are neurologically driven by the lower limbs. It is a bottom up process as we have always said. The arms are largely subservient to the legs, the work as a team, the but quarterback is the pelvis and legs. Obliquity of the pelvis and the antiphasic principles hold true once again in this study. And monkeying with the shoulders and arm swing has a direct effect on the COM, and can thus impact the brains initial choice of optimal step width in any given contact period. Driving more arm movement can over ride inherently hard wired locomotion processes and that can lead to coaching compensatory patterns that should be first driven by lower limb mechanical changes, or coaching recommendations/exercises.
We have discussed that the arms are ballasts, they are there for balance, but also can assist in producing power, but should not be part of the mainstay and dominantly trained process. The process is only "top down" neurologically, meaning the brain is the CPU.

Control and function of arm swing in human walking and running.
J Exp Biol. 2009 Feb;212(Pt 4):523-34. doi: 10.1242/jeb.024927.
Pontzer H1, Holloway JH 4th, Raichlen DA, Lieberman DE.
J Exp Biol. 2009 Mar;212(Pt 6):894. Holloway, John H 3rd [corrected to Holloway, John H 4th].

In this study the authors
" investigated the control and function of arm swing in human walking and running to test the hypothesis that the arms act as passive mass dampers powered by movement of the lower body, rather than being actively driven by the shoulder muscles. We measured locomotor cost, deltoid muscle activity and kinematics in 10 healthy adult subjects while walking and running on a treadmill in three experimental conditions: control; no arms (arms folded across the chest); and arm weights (weights worn at the elbow). Decreasing and increasing the moment of inertia of the upper body in no arms and arm weights conditions, respectively, had corresponding effects on head yaw and on the phase differences between shoulder and pelvis rotation, consistent with the view of arms as mass dampers. Angular acceleration of the shoulders and arm increased with torsion of the trunk and shoulder, respectively, but angular acceleration of the shoulders was not inversely related to angular acceleration of the pelvis or arm. Restricting arm swing in no arms trials had no effect on locomotor cost. Anterior and posterior portions of the deltoid contracted simultaneously rather than firing alternately to drive the arm. These results support a passive arm swing hypothesis for upper body movement during human walking and running, in which the trunk and shoulders act primarily as elastic linkages between the pelvis, shoulder girdle and arms, the arms act as passive mass dampers which reduce torso and head rotation, and upper body movement is primarily powered by lower body movement."

Hallux amputation: Part 1 . What is next for this person ?

The stuff we get/see.
Hallux amputation.
What would you expect to present in this case ?
We will dive into this one next week, but here are some cursory things to consider:

It is the right foot.
-Without the hallux, we cannot wind up the windlass and shorten the distance between the first metatarsal and heel, thus the arch will splay (more permanently over time we suspect) and we cannot optimize the arch height.
This will promote more internal spin on that limb because of more midfoot pronation and poor medial foot tripod stabilization.
- more internal limb spin means more internal hip spin, and more demand (which might not be met at the glute level) and thus loads that are supposed to be buffered with hip stabilization, will be transferred into the low back, and or into the medial knee. Look for more quad protective tone if they cannot get it from the glutes. Troubles arise when we try to control the hip from quadriceps strategies, it is poorly postured to do so, but people do it everyday, *hint: most cyclists and distance runners to a large degree)
- anterior pelvis posturing on the right, perhaps challenging durability of the lower abdominals, hence suspect QL increased protective tone, possible low back tightness or pain depending on duration of activities

- there is so much more, we are just wetting your appetite here on this one.
see you next week on this one gang !

Ivo and i are in the studio for another podcast this afternoon, hope you got to #137 this week ! lots more goodies to come !

cheers, shawn and ivo

Photo permission by patient

We often don't see people when it counts.

Every morning i wake up, and still imaging and feeling i am Dwayne "the rock" Johnston because i had a good roll in jiujitsu class the night before, battling it out with warriors and surviving the blood and submission attempts on my life, like i was in some blockbuster movie fight. And then i step out of bed and the aches and soreness are there. And then i hobble to the bathroom to empty my bladder, and as i turn on the light i am shockingly, every morning, in the mirror reminded i am not The Rock with glorious tatoos and muscles galore, rather a withering 51 year old greying white fart of a man, just trying to keep it together for another 18 hours. 

Driving to work today and I saw this 40 something lady running. It just might have been the most tortured running i have seen in ages.  It made me wonder, when we see our clients at the office and we asked them to run their fresh state they're going to give us their best running, they are naturally going to put out their best for us, even if we ask them to "just run".  The truth is, they haven't been out there for 10-15 miles slogging it out in the heat and the pain and in the dysfunction. They haven't been out in the elements slowly fatiguing stablizers, slowly layering neuroprotective tightness and strategies to offset the fatiguing structures. Even if that lady came in to see me tomorrow, i am not going to see what i saw in here on the side of the road. The clues i might see will be the muscular inhibition, the neuroprotective tightness, the compensations.  And if i put them through a screening method, i am going to see her strategies in the screen to get around all that i mentioned above.

  I think my question for my clients needs to be, be honest with me how ugly does your run get in the later miles when you're in pain?  But then again, that is an impossible question isn't it !? Self awareness has its limitations.  After all, we are human.

Every morning i wake up, and still imaging i am Dwayne "the rock" Johnston because i had a good roll in jiu jitsu class the night before, battling it out with warriors and surviving like i was in some blockbuster movie fight. And then i step out of bed and the aches and soreness is there. And then i hobble to the bathroom to empty my 51 year old bladder, and as i turn on the light i am sockingly, every morning, reminded i am a withering 51 year old greying white fart of a man, just trying to keep it together for another 18 hours. 

And even so, when asked to run at my doctors office, i am still gonna put on my best run for them. I will hide my flaws, my weaknesses, my tightness, my soreness, and give them the best run i have.  The game is on them. Lets see how good they are.

Good luck today comrades, see what you can find and solve in all those who come begging for help, yet doing their best to hide their worst.

Get your foot in High Gear!

image source: Foot Orthoses and Other Conservative Forms of Foot Care. Michaud 1997; Williams an Wilkins: with permission

When it comes to gait, getting the 1st ray to the ground is the name of the game. When weight travels through the medial forefoot and we are able to push off the 1st ray complex, that is called "high gear push off". This was 1st discussed F Bojsen-Møller in this excellent paper (1), that just happens to be a free full text! Craig Payne, The Running Research Junkie has offered and excellent commentary on the topic here as well.

High Gear Push Off can happen when 3 conditions are met: 

1. we have a intact visual, vestibular and kinesthetic systems that ensure we can remain upright in the gravitational plane.
2. we have an intact calcanocuboid locking mechanism
3. we have adequate skill, endurance and strength of our extensor hallucis brevis

The 1st condition is more global and ensures that our cerebellum and vestibular apparatus are playing nice together to create balance, of the literal sort, We seek to keep our visual axes parallel and our center of gravity over our foot. Remember that the BODY will move itself AROUND the visual axes. If the axes are off, the brain will tilt the head and the body will move AROUND the head to accommodate. We have talked about that in these posts here on the blog. 

The 2nd condition, the calcaneo-cuboid locking mechanism, works in the coronal plane and relies on a functioning peroneal group, where the peroneus longus and brevis wrap around the lateral malleolus, cuboid and tail of the 5th metatarsal, crossing the foot diagonally to insert on the base of the 1st metatarsal. When working properly, its actions will be to plantar flex and everting the forefoot, lowering the 1st ray complex down and assisting the shift of the center of gravity more medial for the weight to pass through the medial foot and out through the hallux (ideally). 

The 3rd condition, the ability to descend the 1st ray, relies on the actions of the peroneus, appropriate supination of the forefoot and ability of the extensor hallucis brevis to do its job.  Because the tendon travels behind the axis of rotation of the 1st metatarsal phalangeal joint, in addition to providing extension of the proximal phalynx of the hallux, it can also provide a downward moment on the distal 1st metatarsal (when properly coupled to and temporally sequenced with the flexor hallicus brevis and longus). If the axis of motion for the 1st metatarsal phalangeal joint moves posteriorly, to behind (rather than under) the joint, the plantar pressures increase at MTP’s 4-5 and decrease at the medial mid foot, moving you into low gear push off.  If moved even further posteriorly, the plantar pressures, and contact time in the mid foot and hind foot (2). For more on the extensor hallucis brevis, see our post here.

As you can see, high gear is desirable over low gear push off, but sometimes circumstances or biomechanics do not permit. High gear push off ensures the forefoot is dorsiflexed and everted with respect to the rearfoot and the calcaneocuboid and talonavicular joint axes are perpendicular to one another, giving us a rigid lever to push off of as the center of gravity moves medially across the foot. In low gear push off, the foot is inverted and plantarflexed and the stress falls on the lesser metatarsals and lateral stabilizing complex of the ankle, moving the center of gravity laterally, in addition to the calcaneocuboid and subtalar joint axes being more parallel,  creating a less rigid lever for push off and decreased mechanical efficiency.

1. Calcaneocuboid joint and stability of the longitudinal arch of the foot at high and low gear push off. J Anat. 1979 Aug; 129(Pt 1): 165–176.  link to free full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1233091/

2. van der Zwaard BC1, Vanwanseele B, Holtkamp F, van der Horst HE, Elders PJ, Menz HB Variation in the location of the shoe sole flexion point influences plantar loading patterns during gait. J Foot Ankle Res. 2014 Mar 19;7(1):20.

Posture doesn't matter, until it does.

Awareness is key. Does this person know they are doing this ?  Do they have pain? If they do not have pain or awareness is it a problem and does it need addressed ? These shoes did not make this person load like this, the person broke the shoes into this pattern.  There is something going on, the question is what drove this ?  Most likely, this is not a footwear problem, this is a person problem in the footwear.

What we see is not the problem most of the time. We are seeing their strategies , coping mechanics and their ultimate failure to load more cleanly most of the time.

There are people out in the fields that are saying posture doesn't matter, that your next posture is your best posture. This is a bit curious to us.  Sure, if you are not in pain then is a given posture a problem? One could argue that, but not with a strong argument, we believe.  Take this foot-shoe posturing for example, is this a problem if it is not painful ?  Do we leave it alone if it is not painful? Or do we "head this one off at the pass" before possible pathology or pain presents itself? There are certainly no guarantees, however, one can use some educated and calculated logic and make some reasonable decisions that things are going to go off the rails at some point (or in this case, the heel is going to actually go off the shoe!).  Same for the anti-posture nazi's out there who say posture is not a factor in people's lives.  We are not going to call out people on there personal beliefs, but for us, that is just too extreme thinking. The concept gets some great social media attention, but if you are slouched 90% of your day in a chair or standing at a job, those postures might carry over into other activities and thus matter in time, carrying into aberrant tissue loading.  In our minds, posture does matter, because movement on postures that foster challenging mechanics, lead to challenging loading responses on tissues, and over time, that means change.  Change can be good or bad, sometimes it is how you drive the bus.  Posture can matter in many cases, dismissing if fully is foolish.

So, are you going to change this person's footwear ? Bring it to their awareness ? Look for problems in there body mechanics locally and globally? Or are you just going to say, "foot posturing doesn't matter". Saying it is not a problem, until it is a problem, seems awfully negligent, doesn't it?

Podcast 137: Running: Limitations in thoracic spine function matter

We cover many aspects of human movement on this podcast, the topics are broad ranging on today's show, but they are worthy of your time in our opinion.

direct download: http://traffic.libsyn.com/thegaitguys/pod_138f.mp3

Permalink: http://thegaitguys.libsyn.com/podcast-137-running-limitations-in-thoracic-spine-function-matter

Libsyn: http://directory.libsyn.com/episode/index/id/6866653

Key words:
arm swing, thoracic extension, scapular retraction, arch height, rear foot posting, forefoot loading, ankle dorsiflexion, ankle rocker, shoulder extension, SSEP, F-wave, EMG/NCV testing, gait ataxia
 
Here are some key quotes from today's show:

You may have the range of motion, but are you actually able to use it?
You haven't truly injured yourself, you've just lost your ability to compensate.

And we discuss a case study today, where the following paragraph is germane.

"Abnormal gait changes might be the first signs of an early slow cooking neurologic disorder. Most, not all, pathology is afferent, yet most (not all) EMG/NCV testing is geared towards the efferent pathology (motor end organ disease, not sensory compromise), hence, testing can miss your client's pathology.  We discuss a classic case where the client clearly had the beginnings of a neurologic disorder on our exam (clonus and joint position sense changes and clear ataxic gait) yet the testing "that was done" showed a normal study of this client.  Much pathology is afferent, the input is the problem, so you need to consider requesting Sensory nerve action potentials, SSEP and F-wave testing, because they are difficult to elicit and good technique is paramount. Hence these extra components of the test are not done, and you need to ask for this in your testing.  "Maybe it's not there because you are not looking".  We have much more on this topic, come listen to Podcast 138 and get the full monty."

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.

Gait: When loading COM (center of mass) gets complicated.

When loading COM (center of mass) gets complicated.

Wednesday night on our monthly seminar we discussed some problems with different foot types and how they might load differently compared to others, possible sources of pathology and why someone might have challenges or different strategies in loading the limb over a given foot type. This is just another reason why blanket statements like load the "head over foot" just cannot be made. The COM (center of mass) is subservient to many variables, including how the foot loads, and where its foot loading target is in the step width realm. One just cannot tell or teach everyone to load the head over the foot, it is just foolish to put everyone in that blanket category (besides, it is a category we do not believe is proper or safe). There are just too many variables (genu varum, genu valgum, tibial torsion, femoral torsion, foot types such as rear or forefoot varus or valgus or forefoot supinatus, etc.). The only article we have ever read even suggesting "head over foot", actually said, COM "outside the foot", and that was only during running initiation, the first steps, to get propulsion going, it is not the way we are to run. And over the next few weeks we will continue to write about the problems and repercussions of a COM drift over the foot.

Here was a slide from last night, this is supposedly a drawing of a neutral rearfoot-forefoot relationship, and a relatively neutral pedo mapping of a supposedly neutral foot. But think about this, just because unloaded, during your examination, the foot appears neutral does it mean it will load in that neutral manner. It appears neutral in passive ROM assessment, but under dynamic loading the game can be completely different. For example, what if the tibialis posterior is insufficient? In those cases the rear foot may not support inversion, it might actually valgus load, this can force the loading into premature and sustained pronation issues. Now mind you, if the pedo mapping is dynamic, like we teach it, you will get much of the movement (and compensation) info on the mapping, but many teach static mapping (stand on this, just stand, no walking across it).
But this all comes back to what we say in gait analysis, "what you see is often not the problem, it is the compensation". This is why one must compare one's exam to the dynamic loading challenges your assessment should include, including gait observation. This is also why one is foolish to make gait recommendation off of just what one sees in someone's gait, because you can be recommending changes to an already compensated gait. Just because you think someone will load better in a manner in which you think is better does it mean they can, are able, or capable of doing so without compensation or tissue compromise.
Caveat emptor, and more so, Caveat Venditor (buyer beware, and more so, seller beware).

COM (center of mass) between the feet (inside step width?)

Center of Mass between the feet . . .

The coordinated movement of the spine and pelvis during running. Preece SJ1, Mason D2, Bramah C3.
Hum Mov Sci. 2016 Feb;45:110-8. doi: 10.1016/j.humov.2015.11.014. Epub 2015 Nov 24.

"There appeared to be an anti-phase relationship in the frontal plane between thorax and pelvic motion (Fig. 1b and h)
during stance. Specifically the thorax was laterally flexed towards the stance limb during early stance AND THEN MOVED
TOWARDS A NEUTRAL position during the latter half of stance, as the pelvis became elevated on the contralateral side. The coordination analysis classified the frontal plane pelvis–thorax motion as either anti-phase or pelvis-only during stance (Fig. 4b). This latter classification resulted from the increased motion of the pelvis compared to the thorax which resulted in a more
vertically aligned coupling vector (Seay et al., 2011b) and therefore a coupling angle which was classified as pelvis-only
motion."

This study supports our well founded beliefs that the COM moves within the confines of the step width, it moves TOWARDS, but not over the foot in the early stance phase, and then moves back towards a neutral position during the latter half of stance. One must fully understand the implications of the antiphasic nature in the planes of motion of the body during running (and walking) to understand what the COM is truly doing, what it is not doing, and what it should not be doing.

This study concluded,
"This is the first study to provide an underlying biomechanical rationale for the coordination pattern between the pelvis
and thorax during running in all three body planes. The data showed an anti-phase relationship between these two segments in the sagittal and frontal planes and we suggest that this in a consequence of the requirement to minimise accelerations of the CoM in the AP and ML directions."

The coordinated movement of the spine and pelvis during running. Preece SJ1, Mason D2, Bramah C3.
Hum Mov Sci. 2016 Feb;45:110-8. doi: 10.1016/j.humov.2015.11.014. Epub 2015 Nov 24.

More Flip Flop Madness. Can a flip flop reduce impact forces?

Flip Flop Madness. Can a flip flop reduce loading/impact force? Maybe...

We agree that the increased ankle dorsiflexion moment is to try and keep the flip flop on.  This particular flip flop, the Fit Flop, has different gait parameters (see figure 2 in the article) compared to normal flip flops and barefoot. We hypothesize this is most likely due to the semi rockered design along with the heel cup. Rockered shoes reduce the amount of hallux dorsiflexion needed for forefoot rocker and reduce plantar pressures in the forefoot (1) What surprised us most were the decreased impact forces.

"The current study identified increased ankle dorsiflexor activity in flip-flop style footwear compared to barefoot, coupled with increased dorsiflexion in swing, assumed to be a mechanism to hold the shoe on the foot. The FitFlop limited foot motion in the frontal plane and significantly reduced loading at impact, compared to flip-flop and barefoot. However, it is not clear whether the reductions in these parameters are enough to reduce any potential injury or overuse injuries associated with flip-flop footwear and further, longitudinal, research would be needed to clarify this relationship." (2)

More on the subject with a free, full text below.

 

1. Sobhani S, van den Heuvel E, Bredeweg S, Kluitenberg B, Postema K, Hijmans JM, Dekker R. Effect of rocker shoes on plantar pressure pattern in healthy female runners. Gait Posture. 2014 Mar;39(3):920-5. doi: 10.1016/j.gaitpost.2013.12.003. Epub 2013 Dec 9.

2.  Price C, Andrejevas V, Findlow AH, Graham-Smith P, Jones R. Does flip-flop style footwear modify ankle biomechanics and foot loading patterns? Journal of Foot and Ankle Research. 2014;7:40. doi:10.1186/s13047-014-0040-y.

link to free full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4182831/

Flip Flops not so bad? We still think they suck and here's why...

We have talked about the dangers of open back shoes (Including flip-flops)  and loss of ankle rocker as well as changes in forefoot rocker and great toe dorsiflexion on our blog many times.

The findings of this study, with slower cadence and shortened stance are not surprising (especially since you need to fire your long flexors to keep them on!) nor are ankle joint kinematics (flip flops have no heel counter and are not torsionally rigid, so naturally there would be increseased subtalar motion), however we really question the interpretation.

 "Many have long suspected the answer, but a new study would appear to resolve the question: Are flip flops really that bad for your feet? According to Chen and colleagues from the Department of Biomedical Engineering at The Hong Kong Polytechnic University, flip flops are most likely no better than barefoot when it comes to lower-limb co-contraction and joint contact force in the ankle. The authors had hypothesized that the popular rubber footwear would increase co-contraction of the muscles between the knee and ankle joints in what they thought was a compensatory mechanism for the unstable foot–sole interface and would affect gait kinematics and kinetics.

In the study, the researchers had 10 healthy males perform 6 walking trials under 3 conditions: barefoot, sports shoes, and thong-type flip flops. Participants, who reported they were not “regular flip flop wearers,” were fitted with numerous markers that were monitored while they walked on a 10-meter pathway. The study looked at several muscle pairings that stabilize the knee, ankle, and subtalar joints, including vastus lateralis and gastrocnemius medialis; vastus lateralis and biceps femoris; and peroneus longus and tibialis anterior.

In pairwise comparisons, the walking velocity of flip flops was lower than that of sports shoes (p<0.01) but comparable to barefoot (p>0.05), findings that were consistent with the published literature. Although not significant, the minimalist footwear produced a slower cadence and shortened stance phase in walking trials compared to the other 2 types of footwear. Joint kinematics differed significantly in the ankle joint (F[2,18]=6.73, P<.05) and subtalar joint (F[2,18]=4.45; P<.05); Furthermore, ankle and subtalar range of motion was higher for flip flops than for sports shoes. However, co-contraction was not enhanced. The authors propose that walking speed does not need to be consistent for real-world activities and the slower speed could be a natural approach to avoid injury.

The authors conclude that the slowed walking speed of flip flop users could account for the comparable joint biomechanics between flip flop use and barefoot. They note, however, that, for injury prevention, the closed-toe design of the sports shoe would provide better support for joint motion and loading compared to the other 2 options."

Source:

Chen TL, Wong DW, Xu Z, Tan Q, Wang Y, Luximon A, Zhang M. Lower limb muscle co-contraction and joint loading of flip-flops walking in male wearers. PLoS One. 2018;13(3):e0193653."

image and article source: http://lermagazine.com/issues/may/flip-flops-bare-feet-or-sports-shoes-which-are-best-and-which-are-worst

Hamstring injuries and their gluteal relationship, the dialgoue.

Yesterday we talked about hamstring tears. One of the frequent findings we see in our hamstring injured clients is under performance of the gluteal group. We all are well aware that the hamstrings can be an assistive piece of the posterior chain hip extension pattern in gait. When the glutes are underperforming, under protecting hip stability or underperforming in pelvis control, that the hamstrings can be called upon to do more. The loads an move into the low back or into the leg, or both, when the glutes are underperforming. This study is supportive in an indirect manner.

Sagittal trunk flexion and extension in patients with chronic low back pain.
The study found the duration of gluteus maximus activity was shorter in the back pain patients than in controls during the trunk flexion (p<.05), and it ended earlier during extension. Nothing new here for many of our followers, but it is always worth discussing.

We have talked about the fatigue factor and endurance factor of the paraspinals in low back pain in previous podcasts, maybe a year or two ago. But, in looking for something else in particular today, I came across this article from 2000.
It once again suggests the critical function of the glutes, all 3 divisions and that they do play multiple parts other than just hip stability and movement. We see plenty of clients who have poor development of the upper iliac and sacral divisions of the glute max. This could be from anterior pelvis tilt presentations, faulty movement patterning, or even failure to get to end range hip extension to work on developing that portion of the muscle. Regardless, this once again proves that we are an under-developed glute species and all this sitting is a problem, and even the standing desk trend, will not fix this. The body must move, it must be loaded through to the full range of motion and we must incorporate compound movements with load if we are to get even close to the opportunity to see folks with healthy glutes and thus healthy hips and spines.

"RESULTS:
During early flexion, lumbar paraspinal and biceps femoris were activated simultaneously before gluteus maximus. At the end of flexion and during extension all investigated muscles were activated and relaxed in order. Lumbar paraspinal and biceps femoris muscles were activated in a similar order in low back pain patients and healthy controls during flexion and extension. However, the duration of gluteus maximus activity was shorter in the back pain patients than in controls during the trunk flexion (p<.05), and it ended earlier during extension. Active rehabilitation did not change the muscle activities of lumbar paraspinal and biceps femoris in the back pain patients, but in the measurements after rehabilitation the onset of gluteus maximus activity occurred later in flexion and earlier in extension."

"CONCLUSIONS:
The activity of the gluteus maximus muscle during the flexion-extension cycle was reduced in patients with chronic low back pain. The gluteal muscles should be taken into consideration in the rehabilitation of these patients." - Leinonen et al

Arch Phys Med Rehabil. 2000 Jan;81(1):32-7.
Back and hip extensor activities during trunk flexion/extension: effects of low back pain and rehabilitation.

Leinonen V1, Kankaanpää M, Airaksinen O, Hänninen O.
https://www.ncbi.nlm.nih.gov/pubmed/10638873

Tendinopathy video

Tremendous narrative explaining the Cook and Purdham Continuum Model of Tendon Pathology
*Do not miss this video !

https://www.youtube.com/watch?v=gGicPXm3n30

You need toe extension, more than you might think.

There is a major difference in these 2 photos.One foot is ready for foot loading, the other has one foot over the starting line, and is going to possibly have the risks related to inappropriate loading.

In clients with one of several possible issues related to poor control of the arch during weight bearing loading, it is not all too uncommon for us to bring to their attention that not only do they NOT utilize toe extension appropriately, and at the right time, they just simply have poor strength and endurance of the toe extensors (we will not be bringing up the complicated orchestration of the long and short toe extensors today, lets just keep it loosely as looking at them as a whole for today).

We know we say it an awful lot, that clients need more toe extension endurance and strength. But more often than not, they need more awareness of how little they are actually using their toe extensors during foot loading. This is why we despise flip flops and foot wear without a back strap on them, the flexors have to dominate to keep the footwear on the foot.  And, if you are into your toe flexors, you are definitely not into your toe extensors.

You can easily see in this photo that there is a major difference in the integrity and preparation of the foot arch prior to foot loading in these 2 sample photos. One the toes are up in extension, the other the toes are lazy and neutral.  The toe up photo demonstrates well that when the toes are extended, the Windlass mechanism draws the forefoot and rearfoot together and raises the arch. Go ahead, lift your toes, it will happen on you as well (unless your arch is so collapsed that the first metatarsal actually dorsiflexes during toe extension, in this case, you are a whole different management tier). From this arch raised position, the first metatarsal is adequately plantarflexed, this means the joint complexes proximal and distal to the metatarsals are all in the right position to load and cope with loads. In the toe neutral picture, these components are not prepared, the arch is already getting ready to weight bear load from a half-baked position. One cannot expect the foot complex to load well when it is starting from a position of "half way there". One should start the loading of the foot from the starting line, not 3 steps over the line and not 3 steps before the starting line.  There is no athletic or mechanical endeavor that does well when we start the challenge too soon or too late, timing is everything.

How you choose to prep your foot for contact loading, and yes, there is some conscious choice  here, one is lazy the other is optimal, can determine to a large degree if you or your client is about to fall into the long list of problems related to poorly controlled pronation (too much, too soon, too often, too fast). Any of those bracketed problems lead to improper loading and strains during time under tension.

We will almost always start our clients on our progressing protocol of arch awareness and we will loosely say arch restoration, and attempts at better optimizing the anatomy they have, with toe up awareness.  Many clients will have poor awareness of this component issue, on top of poor endurance and frank weakness. The arch is to a great degree build from a lifting mechanical windlass effect, from the extensors and foot dorslflexors, not from the foot flexors. This is one of our primary beefs with the short foot exercise of Janda, there needs to be a toe extensor component in that exercise (search our blog for why the short foot exercise is dead). The short foot exercise is not actually dead, all exercises have some value when placed and performed properly, but the short foot exercise is based off of the toes being down and utilizing the plantar intrinsics to push the arch up and shorten the foot, this is a retrograde motion and it is not how we load the foot, but, it does have value if you understand this and place it into your clients repertoire appropriately.  This is also why we have some conceptual problems in stuffing an orthotic under someones arch to "lift it up", ie. slow its fall/pronation.  There are times for this, but why not rebuild the proper pathways, patterns and mechanics ?

Teach your clients about toe extension awareness. TEach them that they need to relearn the skill that when the toes drop down to the ground that the arch does NOT have to follow them down, that the client can relearn, "toe up, arch up . . . . . then toes down, but keep the arch up".  IT is a mantra in our office, "don't let your arch play follow the leader".  Reteach the proper neurologic disassociation between the toes and arch.

Perhaps the first place you should be starting your clients with foot and ankle issues, is regaining awareness of proper toe extension from the moment of toe off, maintaining it through swing, and then keeping it until the forefoot has purchase on the ground again, and not any time sooner than that ! If their toes are coming down prior to foot contact, it is quite likely their arch is following the leader.

So, if your client comes in with any of the following, to name just a few:  tibialis posterior tendonitis, plantar fascitis, heel pain, forefoot pain, painful bunions, arch pain, hallux limitus, turf toe, . . . . and the list goes on. Perhaps this will help you get your client to the starting line.

Shawn & Ivo, thegaitguys.com

Step width: Head over foot ?

Step width, "head over foot"?

There has been some decent debate on "head over foot" running biomechanics. We postulate from our years of reading research and studying people's gait (coupled with physical examination, a neuromuscular assessment, not just a visual assumption) that the head should remain within the limits of the step width. This theory falls apart if someone is a crossover gait runner or walker (search our blog for this "cross over gait" idea). IF one is a narrow step width (cross over gait, not a literal cross over of course) then the head must basically be over the foot on each step. But this is a gait with severe limitations and lots of risks and biomechanical problems as we have written about many times, though one can say is has some economical aspects which we have proposed many times.
But, if the head is outside the step width, one is leaning and this resembles a pathologic Trendelenburg gait. Can we definitively then say that when the head is outside the foot contact (beyond the limits of a person's step width) that it is problematic? No, but it is likely pathologic and clearly uneconomical.

So the fence seems to be the head over the foot.
If you are outside that fence even a little, you may be (we strongly believe) on the wrong side of the fence. Look at a CP gait (photo below) for example, point made. So, would you rather be on the other side of the fence? We would, we want to be inside the step width and we are fine going right up against the fence (the head foot) but not over top of it. One cannot just say that the head over the foot is better. What about hip and pelvis stability ? If the hips-pelvis are drifting into the frontal plane, this will put the head over the foot as a default. So does this validate the head over foot theory as good in this client ? No, we see this as a problematic gait all the time, lots of hip and spinal stability issues in these clients. One cannot stand and preach on head over foot alone. We just made the case that in a frontal plane drift pelvis client, this is a compensatory default, but it doesn't make it a good thing, far from it.

For now, we will stay put that, with all other faulty mechanics not present, a more sound head position is to be found between the limits of the step width. Yes, right up to the fence of "head over the foot", but not over top as a sound pattern to play with. Why risk falling over the fence on some steps, Try this, stand on one foot, put your head over the foot. In this position, you had to drift the pelvis laterally into the frontal plane. Now try to effectively engage your glute. Enough said, for now. So why would we promote this as an effective running form? More to come we are certain, but we are open to debate, and to being schooled wrong. If you wish, go into our blog (link below) and read up on the effects of step width on gait, and all of the risks/problems that a narrow step width promotes (ie. head over foot).

https://www.google.com/search?q=the+gait+guys+step+width&ie=utf-8&oe=utf-8&client=firefox-b-1-ab

This simple screening test becomes a form of exercise.

Today we look at a simple CNS screen for your “central pattern generators” or “CPG’s”. If you do not pass, then the exercise becomes the rehab exercise. If you (or your client) does not have good coordination between the upper and lower extremity, then they will not be that efficient, physiologically or metabolically. 

The “cross crawl” or “step test” looks at upper and lower extremity coordination, rather than muscular strength. If performed for a few minutes, it becomes a test that can look at endurance as well. 

It is based on the “crossed extensor” response, we looked at last week. That is, when one lower limb flexes, the other extends; the contralateral upper limb also flexes and the ipsilateral upper limb extends. It mimics the way things should move when walking or running. 
 

• Stand (or have your client stand) in a place where you will not run into anything.
• Begin marching in place.
• Observe for a few seconds. When you (or your client) are flexing the right thigh, the left arm should flex as well; then the left thigh and right arm. Are your (their) arms moving? Are they coordinated with the lower extremity?
• What happens after a few minutes? Is motion good at 1st and then breaks down?
• Now speed up. What happens? Is the movement smooth and coordinated? Choppy? Discoordinated?
• now slow back down and try it with your (their) eyes closed

If  movement is smooth and coordinated, you (they) pass

If movement is choppy or discoordinated, there can be many causes, from simple (muscle not firing, injury) to complex (physical or physiological lesion in the CNS).

• If movement is not smooth and coordinated, try doing the exercise for a few minutes a day. You can even start sitting down, if you (they) cannot perform it standing. If it improves, great; you were able to help “reprogram” the system. If not, then you (they) should seek out a qualified individual for some assistance and to get to the root of the problem.

Physiological Mechanisms of PRP

image source: https://commons.wikimedia.org/wiki/File:Blausen_0740_Platelets.png

We were discussing the efficacy of PRP as well as some of the pros/cons this weekend while recording an upcoming podcast.

This paper did a nice job explaining what we know versus what we do not know at this point in time, regarding the basics science behind it. A referenced, full text article for you:

Yiqin Zhou and James H-C. Wang, “PRP Treatment Efficacy for Tendinopathy: A Review of Basic Science Studies,” BioMed Research International, vol. 2016, Article ID 9103792, 8 pages, 2016. https://doi.org/10.1155/2016/9103792.

link to free full text: https://www.hindawi.com/journals/bmri/2016/9103792/

Running with deep core weakness.

You see something in your client's movement that your eyes (and your present knowledge base) do not like. You decide to implement come well intended corrective work to change these issues you do not like. The risk is, without a prudent clinical examination, which could quite possibly dismiss what you are seeing, or discover that the source is from another cause, that you could be adding a compensation to a client's compensation to an underlying problem.

We discuss this all the time. It is nice to find new paper that supports our suspicion that when we do not fix a problem, merely because we are changing something we see which we do not like, "Muscular compensations may increase risk of muscular fatigue or injury and increased spinal loading over numerous gait cycles and may result in damage to spinal structures. Therefore, insufficient strength of the deep core musculature may increase a runner's risk of developing LBP."

Biomechanical consequences of running with deep core muscle weakness. Raabe ME, Chaudhari AMW
J Biomech. 2017 Dec 6. pii: S0021-9290(17)30692-9. doi: 10.1016/j.jbiomech.2017.11.037. [Epub ahead of print]

Controlling, or at least reducing spinal shear forces is always a desirable outcome. We should all have sufficient strength through the thoraco-lumbo-pelvic interval to protect undesirable forces and loads through the spine. We have discussed this many times on The Gait Guys site/blog during our "antiphasic" biomechanical discussions, ones that have incorporated arm swing, spinal twist/torsional loading and leg swing and whatnot. McGill has discussed this previously as well, mentioning that the degree of antiphasic counter-rotation between the thorax and pelvis reduces as spinal pain is present to reduce compression and shear components.

This paper suggests that improper function of the deep core musculature, defined by this paper as the multifidus, quadratus lumborum, psoas, and deep fascicles of the erector spinae, may lead to abnormal spinal loading, muscle strain, or injury to spinal structures, all of which have been associated with increased low back pain (LBP) risk. "The purpose of this study was to identify potential strategies used to compensate for weakness of the deep core musculature during running and to identify accompanying changes in compressive and shear spinal loads."-Raabe et al.

In this paper, the deep core muscles were weakened individually and together.

"The superficial longissimus thoracis was a significant compensator for 4 out of 5 weakness conditions (p < 0.05). The deep erector spinae required the largest compensations when weakened individually (up to a 45 ± 10% increase in compensating muscle force production, p = 0.004), revealing it may contribute most to controlling running kinematics. With complete deep core muscle weakness, peak anterior shear loading increased on all lumbar vertebrae (up to 19%, p = 0.001). Additionally, compressive spinal loading increased on the upper lumbar vertebrae (up to 15%, p = 0.007) and decreased on the lower lumbar vertebrae (up to 8%, p = 0.008). Muscular compensations may increase risk of muscular fatigue or injury and increased spinal loading over numerous gait cycles may result in damage to spinal structures. Therefore, insufficient strength of the deep core musculature may increase a runner's risk of developing LBP." -Raabe et al.

You see something in your client's movement that your eyes (and your present knowledge base) do not like. You decide to implement come well intended corrective work to change these issues you do not like. The risk is, without a prudent clinical examination, which could quite possibly dismiss what you are seeing, or discover that the source is from another cause, that you could be adding a compensation to a client's compensation to an underlying problem.

We discuss this all the time. It is nice to find new paper that supports our suspicion that when we do not fix a problem, merely because we are changing something we see which we do not like, "Muscular compensations may increase risk of muscular fatigue or injury and increased spinal loading over numerous gait cycles and may result in damage to spinal structures. Therefore, insufficient strength of the deep core musculature may increase a runner's risk of developing LBP."

Biomechanical consequences of running with deep core muscle weakness. Raabe ME, Chaudhari AMW
J Biomech. 2017 Dec 6. pii: S0021-9290(17)30692-9. doi: 10.1016/j.jbiomech.2017.11.037. [Epub ahead of print]

Controlling, or at least reducing spinal shear forces is always a desirable outcome. We should all have sufficient strength through the thoraco-lumbo-pelvic interval to protect undesirable forces and loads through the spine. We have discussed this many times on The Gait Guys site/blog during our "antiphasic" biomechanical discussions, ones that have incorporated arm swing, spinal twist/torsional loading and leg swing and whatnot. McGill has discussed this previously as well, mentioning that the degree of antiphasic counter-rotation between the thorax and pelvis reduces as spinal pain is present to reduce compression and shear components.

This paper suggests that improper function of the deep core musculature, defined by this paper as the multifidus, quadratus lumborum, psoas, and deep fascicles of the erector spinae, may lead to abnormal spinal loading, muscle strain, or injury to spinal structures, all of which have been associated with increased low back pain (LBP) risk. "The purpose of this study was to identify potential strategies used to compensate for weakness of the deep core musculature during running and to identify accompanying changes in compressive and shear spinal loads."-Raabe et al.

In this paper, the deep core muscles were weakened individually and together.

"The superficial longissimus thoracis was a significant compensator for 4 out of 5 weakness conditions (p < 0.05). The deep erector spinae required the largest compensations when weakened individually (up to a 45 ± 10% increase in compensating muscle force production, p = 0.004), revealing it may contribute most to controlling running kinematics. With complete deep core muscle weakness, peak anterior shear loading increased on all lumbar vertebrae (up to 19%, p = 0.001). Additionally, compressive spinal loading increased on the upper lumbar vertebrae (up to 15%, p = 0.007) and decreased on the lower lumbar vertebrae (up to 8%, p = 0.008). Muscular compensations may increase risk of muscular fatigue or injury and increased spinal loading over numerous gait cycles may result in damage to spinal structures. Therefore, insufficient strength of the deep core musculature may increase a runner's risk of developing LBP." -Raabe et al.

https://www.ncbi.nlm.nih.gov/pubmed/29249454

J Biomech. 2018 Jan 23;67:98-105. doi: 10.1016/j.jbiomech.2017.11.037. Epub 2017 Dec 6.Biomechanical consequences of running with deep core muscle weakness. Raabe ME1, Chaudhari AMW2

So, you do weighted carries?

METHODS:

Participants were instructed to ascend and descend a three-step staircase at preferred pace using a right leg lead and a left leg lead for each load condition: no load, 20% body weight (BW) bilateral load, and 20% BW unilateral load. L5/S1 contralateral bending, hip abduction, external knee varus, and ankle inversion moments were calculated using inverse dynamics.

Nothing earthshaking here (1) , but a few takeaways:

• Asymmetric loading of L5-S1 will most likely become more significant if the individual has a L5-S1 facet tropism, where one (or both) of the facets is (are) facing saggitally, as loading will be be even greater.  This has been associated with disc derangement (2) and degeneration (3).

• The body does seem to adjust for the load, but it takes at least to the second step. We need to make sure the proprioceptive feedback loops (joint and muscle mechanoreceptors and their associated pathways) are functioning well. Manipulate, mobilize, facilitate, inhibit as appropriate.

• The increased varus moment and hip abduction on the unweighted side are most likely to move the center of gravity more to the midline, which makes sense. This may become problematic with folks with increased internal tibial torsion, especially with femoral retroversion/torsion as they already have limited internal rotation available to them at the hip

 

1. Wang J, Gillette JC. Carrying asymmetric loads during stair negotiation: Loaded limb stance vs. unloaded limb stance. Gait Posture. 2018 Jun 19;64:213-219. doi: 10.1016/j.gaitpost.2018.06.113. [Epub ahead of print]

2. Chadha M, Sharma G, Arora SS, Kochar V. Association of facet tropism with lumbar disc herniation. European Spine Journal. 2013;22(5):1045-1052. doi:10.1007/s00586-012-2612-5.

3. Berlemann U, Jeszenszky DJ, Buhler DW, Harms J (1998) Facet joint remodeling in degenerative spondylolisthesis: an investigation of joint orientation and tropism. Eur Spine J 7: 376-380.

Abstract

BACKGROUND:

Individuals often carry items in one hand instead of both hands during activities of daily living. Research Question The purpose of this study was to investigate low back and lower extremity frontal plane moments for loaded limb stance and unloaded limb stance when carrying symmetric and asymmetric loads during stair negotiation.

METHODS:

Participants were instructed to ascend and descend a three-step staircase at preferred pace using a right leg lead and a left leg lead for each load condition: no load, 20% body weight (BW) bilateral load, and 20% BW unilateral load. L5/S1 contralateral bending, hip abduction, external knee varus, and ankle inversion moments were calculated using inverse dynamics.

RESULTS:

Peak L5/S1 contralateral bending moments were significantly higher when carrying a 20% BW unilateral load as compared to a 20% BW bilateral load for both stair ascent and stair descent. In addition, peak L5/S1 contralateral bending moments were significantly higher during step one than for step two. Peak external knee varus and hip abduction moments were significantly higher in unloaded limb stance as compared to loaded limb stance when carrying a 20% BW unilateral load.

SIGNIFICANCE:

General load carriage recommendations include carrying less than 20% BW loads and splitting loads bilaterally when feasible. Assessment recommendations include analyzing the first stair step and analyzing both the loaded and unloaded limbs.

What were you thinking?

We were just talking about cognitive tasking and arm swing, and have talked about cognition altering gait. Here is a another paper on cognition (or inattention in this case) boding not so well

ABSTRACT: We examined factors related to conditions of life function and falls, including eye movements and gait variability, in community-dwelling older adults in Japan.

METHODS: Participants were 82 older adults (21 men, 61 women, mean age 76.1 years). We measured eye movements and gait variability during walking, and cognitive, attentional and life function. We compared two groups according to their fall history, and used a multiple logistic regression analysis to determine its relevance.

RESULTS: Fixation time, which was estimated from eye movements during obstacle crossing, and gait variability (vertical) were significantly associated with falls. There was also a significant correlation between fixation time and gait variability during obstacle crossing. In other words, the higher the gait variability in older adults, the higher the risk of falls, which was due to reduced attention estimated from eye movements during obstacle crossing that required obstacle avoidance.

CONCLUSIONS: These results show that poor attention during gait is a critical risk factor for falls in community-dwelling older adults. For fall prevention, it is necessary to promote exercises for attention, and to maintain an older adult-friendly pedestrian environment.

Inoue T, Kamijo K, Haraguchi K, Suzuki A, Noto M, Yamashita Y, Nakamura T. Risk factors for falls in terms of attention during gait in community-dwelling older adults. Geriatr Gerontol Int. 2018 Jun 27. doi: 10.1111/ggi.13462. [Epub ahead of print]