Deep brain stimulation and movement.

We talk much about movement patterns and movement problems here and on our blog. In recent years there has been much research on stimulating the subthalamic nucleus with deep brain stimulation (STN-DBS) to alter freezing of gait (FOG) in patients with advanced Parkinson’s disease. We will likely see more and more research, and likely therapeutic options in time, on deep brain stimulation (DBS). The future looks bright. If you want to get into the deeper stuff, search Pubmed for DBS.
From the article:
“There are more than 100 nervous system disorders that afflict millions of people across the globe. Many of the disorders affect a person’s movement and alter their motor controls. This includes balance, gait, speed of movement, tremors, jerks and abnormal postures. Deep brain stimulation or DBS has successfully treated these symptoms and allowed many sufferers to reclaim their lives.”
Read more here …

http://brainmysteries.com/deep-brain-stimulation-movement-disorders-tuning-brain/

Corticospinal axon regeneration.

In the world of gait challenges from spinal cord injury, this is potentially huge.
“In the July 1st issue of The Journal of Neuroscience, HKUST researchers report that the deletion of the PTEN gene would enhance compensatory sprouting of uninjured CST axons.”

“It not only promoted the sprouting of uninjured CST axons, but also enabled the regeneration of injured axons past the lesion in a mouse model of spinal cord injury, even when treatment was delayed up to 1 year after the original injury. The results considerably extend the window of opportunity for regenerating CST axons severed in spinal cord injuries.”

http://www.deepstuff.org/researchers-discover-way-to-regenerate-corticospinal-tract-axons/

It is not your gait, it is where you take it

Often, it is not your gait, it is where you take it and make use of it.

“Specifically, the study finds that people who walked for 90 minutes in a natural area, as opposed to participants who walked in a high-traffic urban setting, showed decreased activity in a region of the brain associated with a key factor in depression.”
In the next few decades it is projected that 70% of the world’s population will exist in urban settings. Urbanization and disconnection from nature have grown dramatically, as have mental disorders such as depression.
“In fact, city dwellers have a 20 percent higher risk of anxiety disorders and a 40 percent higher risk of mood disorders as compared to people in rural areas. People born and raised in cities are twice as likely to develop schizophrenia.”

http://www.futurity.org/nature-depression-951762/

XBox and gait analysis

The revised Xbox One Kinect, also known as the Microsoft Kinect V2 for Windows, includes enhanced hardware which may improve its utility as a gait assessment tool.
“In conclusion, while the Kinect V2 body tracking may not accurately obtain lower body kinematic data, it shows great potential as a tool for measuring spatiotemporal aspects of gait.”

J Biomech. 2015 May 28. pii: S0021-9290(15)00298-5. doi: 10.1016/j.jbiomech.2015.05.021. [Epub ahead of print]
Gait assessment using the Microsoft Xbox One Kinect: Concurrent validity and inter-day reliability of spatiotemporal and kinematic variables.
Mentiplay BF

The gluteus medius and low back pain.

We see this one ALL the time. We are sure you do as well.
“Gluteus medius weakness and gluteal muscle tenderness are common symptoms in people with chronic non-specific LBP.”
It is often more on the side of pelvic frontal plane drift. The abdominals and spinal stabilizers also often test weak on this same side. We often see compromise of hip rotation stability as well because , since the hip is relatively adducting (because the pelvis is undergoing repeated frontal plane drift, hence no hip abduction) there is often a component of cross over gait phenomenon which can threaten rotation stability of the lower limb (type “cross over gait” into the search box of our tumblr blog for a landslide of work we have written on that phenomenon).

Eur Spine J. 2015 May 26. [Epub ahead of print]
Prevalence of gluteus medius weakness in people with chronic low back pain compared to healthy controls.
Cooper NA1, Scavo KM, Strickland KJ, Tipayamongkol N, Nicholson JD, Bewyer DC, Sluka KA.

http://www.ncbi.nlm.nih.gov/pubmed/26006705

Abs on the UP, Glutes on the DOWN

I had the opportunity to go on my 1st mountain bike ride of the season last Sunday morning. Yes, I am aware it is JUNE, but the snow has finally melted (we had over 7 FEET at arapahoe Basin in May) and you need to understand that I am usually a runner). In the cool morning 44 degree air I was reminded of the importance of my gluteal muscles (rather than just my quads) while climbing a technical hill which was clearly pushing my aerobic capacity. We have the opportunity to perform many bike fits in the office and treat many cycling ailments. We also train and retraing pedal stroke and one of our mantras (in addition to skill, endurance and strength) is “Glutes on the downstroke; Abs on the upstroke”. Meaning use your glutes to extend the hip from 12 to 6 o’clock and use your abs to initiate the upstroke. Quadricep (on the downtstroke) and hamstring dominance (on the upstroke) is something we see often and this mantra often proves useful in the “retraining process”.

I have been a fan of Ed Burkes work (“Serious Cycling” and “Competitive Cycling”) for years and have read (and lectured about) these books many times. In my effort to find a basis in the literature for my mantra, I ran across a paper (1) that seemed to substantiate, at least in part, the mantra. It is a small study looked at elite athletes that explores changes that occur in muscle recruitment as the body fatigues after a sub maximal exercise session.

Their conclusion “The large increases in activity for gluteus maximus and biceps femoris, which are in accordance with the increase in force production during the propulsive phase, could be considered as instinctive coordination strategies that compensate for potential fatigue and loss of force of the knee extensors (i.e., vastus lateralis and vastus medialis) by a higher moment of the hip extensors.”

This makes sense, although may be contradicted by this study (2), which showed LESS gluteal activity at higher mechanical efficiency, with increased tricep surae activity. They conclude “These findings imply that cycling at 55%-60% V˙O(2max) will maximize the rider’s exposure to high efficient muscle coordination and kinematics.”  Although this study looks at mechanical efficiency and the 1st lloks at muscle activity.

Being seated on a bike and having your torso, as well as hips flexed is not the most mechanically efficient posture for driving the glutes, but clinical observation seems to dictate that the less quad and hamstring dominant people are on the down and up stroke respectively, then the more pain free they are. This does not always equte to being the fastest, but it does equate to fewer injuries showing up in the office.

1. Dorel S1, Drouet JM, Couturier A, Champoux Y, Hug F. Changes of pedaling technique and muscle coordination during an exhaustive exercise. Med Sci Sports Exerc. 2009 Jun;41(6):1277-86. doi: 10.1249/MSS.0b013e31819825f8.
2. Blake OM1, Champoux Y, Wakeling JM.  Muscle coordination patterns for efficient cycling. Med Sci Sports Exerc. 2012 May;44(5):926-38. doi: 10.1249/MSS.0b013e3182404d4b.

Abductory twist in your gait ?

Last night on our www.onlinece.com teleseminar we discussed some clinical applications and critical thinking of gait parameters and pathology. We discussed the dynamic gait pedograph below. Possible evidence of Abductory Twist gait pathology (video linkhttps://youtu.be/F3DHRoHrYOs). In this case, client had loss of internal hip rotation, but they sure love external rotation pivot at the ground interface, as the pedo shows here (more details were provided on the teleseminar last night).
*Fix the problem, retrain normal gait skills, add endurance and strength to the new gait pattern and you have a solution. Add an orthotic to treat what you see on the pedograph and you have a bandaid (and potentially/probably a problem down the road). You can’t fix a motor pattern compensation by forcing a compensatory fix. Get to the root of the problem, in this case hip and pelvic biomechanics ! It is all about mobility and stability ! 

Cross Fit: Gray Cooks thoughts

Always a good read, he is always on the mark.
Gray Cook talks about CrossFit, injury rates, and protecting both elite and amateur level CrossFit athletes.
We couldn’t agree more about the fact that CrossFit often prioritizes reps and time which can lead to fatigue and compensation in lifters, often corrupting and even neglecting technique. (yes, not everyone and not ever cross fit gym, but enough that its worthy of dialogue).
https://www.t-nation.com/t…/how-to-prevent-crossfit-injuries

Gait changes on a treadmill

Something to ponder on those days when getting outside it just impossible because of weather.
Athletes might respond to fatigue differently when running on a treadmill compared with overground conditions, where pace is typically more variable.
“Before halfway, step length increased and cadence decreased, whereas during the latter stages, there were significant decreases in impulse and maximum force. Contact time decreased and flight time increased continually, but otherwise most gait variables did not change. The changes in contact and flight times suggested that athletes altered their gait so that more time was spent airborne to allow the treadmill to pass under them. In general, however, the runners maintained their techniques throughout the run. ”

http://www.ncbi.nlm.nih.gov/m/pubmed/23860291/

Muscle activity

Does variability in muscle activity reflect a preferred way of moving or just reflect what they’ve always done? In this study it was found that there isn’t always this tight relationship between activity in the muscles and the movement we’re seeing.
“Clearly, locomotion is not as simple as we thought it was,” Foster said. “This decoupling – big changes in movement without corresponding changes in muscle activity – suggests there are other important factors going on and we need to better understand them if we want to reproduce these movements in prosthetics or robotics.”
Hmmmm. thoughts. this makes everything more interesting doesn’t it ?!

http://esciencenews.com/articles/2014/03/14/motion.and.muscles.dont.always.work.lockstep.researchers.find.surprising.new.study

Muscle activity and movement

“We expected to see a one-to-one correlation between the muscle activity and movements because motion is generally driven by muscles,” Higham said, “but as we changed the structure of their habitat and they changed their motions, we were surprised to find very few accompanying changes in muscle activity.”

Context-dependent changes in motor control and kinematics during locomotion: modulation and decoupling. Foster and Higham
http://www.ncbi.nlm.nih.gov/pubmed/24621949

Gait on slippery floors.

You seem to see a glossy wetness to the tile floor ahead of you in the supermarket. Is that just a really polished floor or is that water? Hey, it might be slippery, lets make some adaptive changes up there in the brain.
Postural and temporal gait adaptations, which affected ground reaction forces occur.
This study found that “statistically significant gait adaptations included reductions in stance duration (SD) and loading speed on the supporting foot, shorter normalized stride length (NSL), reduced foot-ramp angle and slower angular foot velocity at heel contact. As a result of these adaptations, anticipation of slippery surfaces led to significant changes in lower extremity joint moments, a reflection of overall muscle reactions.”
Significant gait changes occur when there is percieved risk of slipping, and in this study, “even though subjects were asked to walk as naturally as possible”.

Changes in gait when anticipating slippery floors.
Cham R, et al. Gait Posture. 2002.
http://www.ncbi.nlm.nih.gov/m/pubmed/11869910/

Reteaching sensory-motor patterns

Trying to reteach your client’s CNS new sensory-motor patterns so they can move better ? We like to say that the first few weeks are like paying down a mortgage, you do not own them, you are cerebrally renting those changes and barely paying down the principle. It takes focused work and time to truly own the changes so that they translate into better movement.
“Depending on the complexity of the activity, [experiments have required] four and a half months, 144 days or even three months for a new brain map, equal in complexity to an old one, to be created in the motor cortex.” -Swart
New connections and pathways are fragile and only through repetition and practice and focused attention can those connections be established enough to become habitual or default behaviors.

Neuroscience for Leadership: Harnessing the Brain Gain Advantage (The Neuroscience of Business). Tara Swart

Ankle Plantarflexors as Gait compensators ?

We are always talking about compensations. We have worn out our statement “what you see in someone’s gait is not their problem, ti is their compensation stratetgy(s).”
Here is a study with an interesting thought.
Just remember, try to fix the underlying problems. But, realizing sometimes you cannot, especially in the elderly population, sometimes you have to give a strategy to help them even though it is not the solution you want. And remember also that driving the anterior compartment with appropriate exercises as our “shuffle walk” might stop any loss of ankle dorsiflexion that might be met with the extra calf work that this article seems to suggest.

From the study: “ Of particular importance were the compensatory mechanisms provided by the plantar flexors, which were shown to be able to compensate for many musculoskeletal deficits, including diminished muscle strength in the hip and knee flexors and extensors and increased hip joint stiffness. This importance was further highlighted when a normal walking pattern could not be achieved through compensatory action of other muscle groups when the uniarticular and biarticular plantar flexor strength was decreased as a group. Thus, rehabilitation or preventative exercise programs may consider focusing on increasing or maintaining plantar flexor strength, which appears critical to maintaining normal walking mechanics.”

Gait Posture. 2007 Mar;25(3):360-7. Epub 2006 May 23.
Compensatory strategies during normal walking in response to muscle weakness and increased hip joint stiffness.
Goldberg EJ1, Neptune RR.
http://www.ncbi.nlm.nih.gov/pubmed/16720095

Achilles Tendonitis

The motion needs to occur somewhere…Make sure you look at the whole picture

Since the knee was bent, perhaps we should be looking at the soleus? And the talo crural articulation?

“A more limited ankle Dorsi Flexion Range Of Motion as measured in Non Weight Bearing with the knee bent increases the risk of developing Achilles Tendonitis among military recruits taking part in intensive physical training.”

J Foot Ankle Res. 2014 Nov 18;7(1):48. doi: 10.1186/s13047-014-0048-3. eCollection 2014.
Limited ankle dorsiflexion increases the risk for mid-portion Achilles tendinopathy in infantry recruits: a prospective cohort study.
Rabin A1, Kozol Z1, Finestone AS2.

GOT GLUTE MEDS?

Want to strengthen that gluteus medius we were talking about Monday? Have you considered walking lunges with dumbbells? These seem to activate the side contralateral to a better extent than split squats.

We wonder if you get the same effect with a medicine ball. Anyone out there have some data or experience with that?

Stastny P1, Lehnert M, Zaatar Zaki AM, Svoboda Z, Xaverova Z. DOES THE DUMBBELL CARRYING POSITION CHANGE THE MUSCLE ACTIVITY DURING SPLIT SQUATS AND WALKING LUNGES? J Strength Cond Res. 2015 May 8. [Epub ahead of print]

Foot orthoses and patellofemoral pain: frontal plane effects during running | Lower Extremity Review Magazine→

We all see people with patellofemoral pain. Some of those cases may have responded to orthotic therapy. Some studies show that the effects on frontal plane kinematics are minimal (1 degree); this doesn’t mean it didn’t work, or this amount is not clinically significant. So why do they help? Perhaps it is a “timing” issue and the knee abduction moment.

“Our results are consistent with a 2003 study by Mundermann et al that compared the effects of custom orthoses (with posting, molding, or a combination of both) to flat inserts. For each orthotic condition, these authors reported a significant delay in the timing of the peak knee abduction moment. This finding may be related to the aforementioned clinical effects, as delaying the peak knee abduction moment would effectively decrease the rate of loading at the knee joint. The rate of loading has been previously implicated as a possible contributing factor in running-related overuse injuries, as runners with a history of injury have demonstrated a higher rate of loading of the vertical ground reaction force than runners with no history of running-related injury.”

This is an interesting take. If you have a few moments, give it a read:

Lumbar link? Ankle, spinal pathologies coexist in cadavers | Lower Extremity Review Magazine→

It makes sense…but which came 1st?

Just make sure you ask your foot patients about their back, and your back patients about their feet

The Gait Guys

Forefoot Varus or Forefoot Supinatus?

Forefoot varus is a fixed, frontal plane deformity where the forefoot is inverted with respect to the rearfoot. Forefoot varus is normal in early childhood, but should not persist past 6 years of age (i.e. when developmental valgus rotation of forefoot on rearfoot is complete, and plantar aspects of fore- and rearfoot become parallel to, and on same plane as, one another (1)

Forefoot supinatus is the supination of the forefoot that develops with adult acquired flatfoot deformity. This is an acquired soft tissue adaptation in which the forefoot is inverted on the rearfoot. Forefoot supinatus is a reducible deformity. Forefoot supinatus can mimic, and often be mistaken for, a forefoot varus. (2)

A forefoot varus differs from forefoot supinatus in that a forefoot varus is a congenital osseous where a forefoot supinatus is acquired and develops because of subtalar joint pronation.

“Interestingly, only internal rotation of the hip was increased in subjects with FV – no differences were present in hip adduction and knee abduction between subjects with and without FV. The authors nevertheless conclude that FV causes significant changes in mechanics of proximal segments in the lower extremity and speculate that during high-speed weight-bearing tasks such as running, the effects of FV on proximal segments in the kinetic chain might be more pronounced.”

We wonder if the folks in this study had a true forefoot varus, or actually a forefoot supinatus (3).

The Gait Guys

1. Illustrated Dictionary of Podiatry and Foot Science by Jean Mooney © 2009 Elsevier Limited.

2. Evans EL1, Catanzariti AR2. Forefoot supinatus.
Clin Podiatr Med Surg. 2014 Jul;31(3):405-13. doi: 10.1016/j.cpm.2014.03.009.

3. Scattone Silva R1, Maciel CD2, Serrão FV3. The effects of forefoot varus on hip and knee kinematics during single-leg squat. Man Ther. 2015 Feb;20(1):79-83. doi: 10.1016/j.math.2014.07.001. Epub 2014 Jul 12.

Foam rolling, a literature review - Anatomy & Physiotherapy→

What does the literature say about foam rolling?

The folks here bring up a good point: “ Despite these findings, without clearly defined parameters and more importantly, mechanisms of action, to what extent should we incorporate SMR and foam rolling into our programming?”