How about that arm swing?

Do you ever notice that sometimes when people have a problem with one of their lower extremities, there are arm swing changes? Usually on the opposite side? This can be anything from a short leg to lack of ankle dorsiflexion, lack of hip extension or even over pronation.

Many times, gait changes, including arm swing, are an "above down" process. This means it begins in the cortex, affects the pattern generators which subsequently will affect extremities distal to that. Sometimes this is a metabolic problem, sometimes vestibular (which can also be mechanical, causing decreased joint and muscle mechanoreceptor input to the cerebellum and vestibular nucleii), sometimes a combination of both. Throw a figure-of-eight ankle wrap on and walk. Your ROM is decreased (mechanical); this reduces input to your cerebellum which reduces input to your vestibular system. Your ankle dorsiflexion and step length will be diminished on that side; this will often cause an increase in arm swing on the contralateral side, which increases the metabolic "cost".

Arm swing may be coached, but we believe this is not always the correct approach as if it is a vestibular problem with altered cerebellar input (Something with the actual semicircular canals or perhaps input from muscle spindle or Golgi tendon organs), coaching arm swing makes the patient "look better" but does not really "fix" the problem; Which may be something as simple as joint pathomechanics, ligamentous restriction or a lack of skilled/endurance/strength in appropriate musculature.  If it is a metabolic issue, sometimes coaching arm swing can improve mechanical efficiency but at the cost of decreasing cortical efficiency, because the brain is such an energy hog.

Arm swing is there for a reason. It tells you something about what is going on or what is not going on. Just because it looks bad does not mean that it is necessarily the problem. Look deeper and keep your eyes, ears and mind open.

We will be talking about the case with this gal. her crossover gait and armswing, alonng with 2 other cases, on our 3rd Wednesdays class on onlince.com: Biomechanics 320  on 8/15/2018

Meyns P, Bruijn SM, Duysens J. The how and why of arm swing during human walking. Gait Posture. 2013 Sep;38(4):555-62. doi: 10.1016/j.gaitpost.2013.02.006. Epub 2013 Mar 13.

Wu Y, Li Y, Liu AM, Xiao F, Wang YZ, Hu F, Chen JL, Dai KR, Gu DY. Effect of active arm swing to local dynamic stability during walking. Hum Mov Sci. 2016 Feb;45:102-9. doi: 10.1016/j.humov.2015.10.005. Epub 2015 Nov 23.

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/

Welcome to Monday and News You Can Use. Got Arm swing? This exercise, borrowed from Shirley Saurmann can be a great adjunct to your rehab program, dispensed with some muscle physiology : )

Do it on your self
Try it on a client
Teach someone else

Got Arm Swing?

We have written many times about arm swing. Click here for some of our posts here on Tumblr.

Here we are again at the beach. Look at the beautiful difference in arm swing from side to side in the guy carrying the bag. Makes you want to tell him to use a backpack, eh?

Never mind what it does to his gait

• decreased arm swing on the carrying side
• increased step length on the left side
• increased thigh flexion of the left side
• increased body lean and head tilt to right side (Take a look at this paper)

think about the increased metabolic cost. Think about what this  type of input (increased amplitude of movement unilaterally) is doing to your cortex!

keep your movements symmetrical, folks!

The Gait Guys

Correcting a cross over gait with arm swing? Is it really THAT easy? Sometimes, yes!

We noticed this patient had a cross over gait while running (1st few seconds of video. need to know more about crossover gait? click here). We noted she was crossing her arms over her body as well. We than had her run her hands and arms straight out. See the crossover disappear? Need to know more about arm swing? click here

We the had her do the same while walking. Easier to see, eh? That’s because it is often easier to “fudge” things when you are moving faster (ie: the basal ganglia of nervous system can interpolate where the body part is supposed to be, and because of momentum, there is less need for precision). When we do things slowly (like the 3 second Test), more precision is needed. Watch this short video clip a few more times.

The arms are essentially adducting when the arms cross over. The arms are reciprocally paired with the contralateral lower extremity. When you make a change in one, you often will make a change in the other.

Subtle. Yes. Easier to see when the task becomes more difficult. Yes. Pay attention, the answer is often right there if you look closely enough.

Providing the clues to help you be smarter, better, faster, stronger; we are The Gait Guys

special thanks to “Q” for allowing us to publish this video : )