Children: Postural control of balance

From the study:

“From these indexes it was established that the postural capacity needed just to control balance with the leg muscles was not attained before 4-5 years of independent walking, i.e., at about 5-6 years of age.” -Breniere

reference link:

Exp Brain Res. 1998 Aug;121(3):255-62.Development of postural control of gravity forces in children during the first 5 years of walking.Brenière Y1, Bril B.

http://www.ncbi.nlm.nih.gov/pubmed/9746131/

Finishing up the week on kids and gait, here is a rewind that talks about proprioceptive clues and gait. It all goes back to the beginning…

Have a great weekend

The Gait Guys

Things may not always be how they appear.

What can you notice about all these kids that you may not have noticed before?

Look north for a moment. What do you notice about all the kids with a head tilt? We are talking about girl in pink on viewers left, gentleman in red 2nd from left, blue shirt all the way on viewers right. Notice how the posture of the 2 on the left are very similar and the one on the right is the mirror image?

What can be said about the rest of their body posture? Can you see how the body is trying to move so that the eyes can be parallel with the horizon? This is part of a vestibulo cerebellar reflex. The system is designed to try and keep the eyes parallel with the horizon. The semicircular canals (see above), located medial to your ears, sense linear and angular acceleration. These structures feed head position information to the cerebellum which then forwards it to the vestibular nucleii, which sends messages down the vestibulo spinal tract and up the medial longitudinal fasiculus to adjust the body position and eye position accordingly. 

Can you see how when we add another parameter to the postural position (in this case, running; yes, it may be staged, but the reflex persists despite that. Neurology does not lie), that there can be a compensation that you may not have expected?

What if one of these 3 (or all three) kids had neck pain. Can you see how it may not be coming from the neck. What do you think happens with cortical (re)mapping over many years of a compensation like this? Hmmm. Makes you think, eh?

Ivo and Shawn. The Gait Guys. Taking you a little further down the rabbit hole, each and every post.

Well, how convenient. A fantastic picture for teaching from the cover of one of our favorite magazines.

For this post, lets start with the gal on the left in the pink shirt. 1st of all, she is running in flip flops. Since these require so much long flexor activity to keep them on, not the best footwear choice, in our opinion. Check out that exaggerated left sided arm swing. This goes to propel herself forward. Why the extra effort? Check out her right (stance phase leg). What do you see? The knee points outward while the foot is planted. We are looking at either external tibial torsion or a femoral retrotorsion. Did you pick up the compensatory head tilt to the left? The vestibular system has become involved, and the trapezius and levator scapula seem to be it’s target (thus the shoulder hike and ipsilateral rotation), as well as the ipsilateral lateral benders and rotators of the cervical spine, namely the splenius cervicis and capitis (the multifidus/rotatores are contralateral rotators).

How about the subtle pelvic shift to the right? and the mild crossover gait (note the adduction of the left knee across midline).

It would be great to see a shot of her barefoot to see what changes, as increased long flexor activity has both local (impaired ankle rocker, excessive forefoot inversion, reciprocal inhibition of the anterior compartment muscles of the lower leg) as well as long distance (namely increased flexor drive to the brainstem and cerebellum) implications. We would want to see this (as well as examine her) before making any recommendations other than LOSE THE FLIP FLOPS GIRLFRIEND.

Wow, all that and we have only scratched the surface.

We remain the geeks of gait: Ivo and Shawn

Remember this kiddo?

We have been following the natural development of this little guy for some time now. For a review, please see here (1 year ago) and here (2 years ago) for our previous posts on him.

In the top 2 shots, the legs are neutral. The 3rd and 4th shots are full internal rotation of the left and right hips respectively. The last 2 shots are full external rotation of the hips.

Well, what do you think now?

We remember that this child has external tibial torsion and pes planus. As seen in the supine photo, when the knees face forward, the feet have an increased progression angle (they turn out). We are born with some degree / or little to none, tibial torsion and the in-toeing of infants is due to the angle of the talar neck (30 degrees) and femoral anteversion (the angle of the neck of the femur and the distal end is 35 degrees).  The lower limbs rotate outward at a rate of approximately 1.5 degrees per year to reach a final angle of 22 degrees….. that is of course if the normal de rotation that a child’s lower limbs go through occurs timely and completely.

He still has a pronounced valgus angle at the the knees (need a review on Q angles? click here). We remember that the Q angle is negative at birth (ie genu varum) progresses to a maximal angulation of 10-15 degrees at about 3.5 years, then settles down to 5-7 degrees by the time they have stopped growing. He is almost 4 and it ihas lessend since the last check to 15 degrees.

His internal rotation of the hips should be about 40 degrees, which it appears to be. External rotation should match; his is a little more limited than internal rotation, L > R. Remember that the femoral neck angle will be reducing at the rate of about 1.5 degrees per year from 35 degrees to about 12 in the adult (ie, they are becoming less anteverted).

At the same time, the tibia is externally rotating (normal tibial version) from 0 to about 22 degrees. He has fairly normal external tibial version on the right and still has some persistent internal tibial version on the left. Picture the hips rotating in and the lower leg rotating out. In this little fellow, his tibia is outpacing the hips. Nothing to worry about, but we do need to keep and eye on it.

What do we tell his folks?

  • He is developing normally and has improved significantly since his original presentation to the office
  • Having the child walk barefoot has been a good thing and has provided some intrinsic strength to the feet
  • He needs to continue to walk barefoot and when not, wear shoes with little torsional rigidity, to encourage additional intrinsic strength to the feet
  • He should limit “W” sitting, as this will tend to increase the genu valgus present
  • We gave him 1 leg balancing “games” and encouraged agility activities, like balance beam, hopping, skipping and jumping on each leg individually

We are the Gait Guys, promoting gait and foot literacy, each and every post.

The power to bend bones.

What have we here? Hmmm. This little girl was brought in by her mother because of intermittent knee pain and “collapsing” of the knees while walking, for no apparent reason.

The ankle dorsi flexion (or ankle rocker; see last 2 pictures; we are fully dorsiflexing the ankles)  needs to occur somewhere, how about the knees? Or in this case, the tibia. Wow!

You are looking at a 4 year year with a condition called genu (and tibial) recurvatum. Genu recurvatum is operationally defined as knee hyperextension greater than 5 degrees. The knee is hyperextended, and in this case, the tibia is literally “bent backward”. Look at the 2 pictures of her tibia.

Generally speaking, the tibial plateau usually has a slight posterior inclination (as it does in this case; look carefully at the 1st picture) causing the knee to flex slightly when standing. Sometimes, if it is parallel with the ground and the center of gravity is forward of the knees, the knee will hyperextend (or in this case, the tibia will bend) to compensate.

In this particular case, the tibia has compensated more, rather than the knee itself. The knee joint is stable and there is no ligamentous laxity as of yet. She does not have a neurological disorder, neuromuscular disease or connective tissue disorder. She has congenitally tight calves.

As you can imagine, her step length is abbreviated and ankle rocker is impaired.

So what did we tell her Mom?

  • keep her barefoot as much as possible (incidentally, she loves to be barefoot most of the time, gee, go figure!)
  • have her walk on her heels (she’s a kid, make a game of it)
  • showed her how to do calf stretches
  • balance on 1 leg with her eyes open and closed
  • keep her out of backless shoes (like the clogs she came in with)
  • keep her out of flip flops and sandals where she would have to “scrunch” her toes to keep them on.
  • follow back in 3 months to reassess

There you have it. Next time you don’t think Wolff’s (or Davis’s) law* is real, think about this case. Want to know more? Consider taking our National Shoe Fit Program, available by clicking here.

The Gait Guys. Making you gait IQ higher with each post.

*Wolff’s law: Bone will be deposited in areas of stress and removed in areas of strain. or put another way: bone in a healthy person or animal will adapt to the loads under which it is placed

Davis’s law: soft tissue will adapt to the loads that are placed on it

Treat your children well.

We think Crosby, Stills, Nash and Young had it right…

look at this conclusion: “Shoes affect the gait of children. With shoes, children walk faster by taking longer steps with greater ankle and knee motion and increased tibialis anterior activity. Shoes reduce foot motion and increase the support phases of the gait cycle. During running, shoes reduce swing phase leg speed, attenuate some shock and encourage a rearfoot strike pattern.”                                                                   

let’s break that down a bit:

“Shoes affect the gait of children.” Shoes effect EVERYONE’S gait, not just kids. They alter the ground reactive forces, limit some ranges of motion and thus can promote a compensation or mechanics that you may not have seen previously. Take off one of your shoes. Lift your toes up slightly so you are centered on your tripod. Stand on your “barefoot” leg with your eyes closed. See how long you can stand without faltering. Now repeat that with your shod foot. Some difference, eh? I thought shoes dampened proprioception…They do. But they also give you more support and mechanics that you didn’t have previously, so the foot doesn’t have to work as hard. 

“With shoes, children walk faster by taking longer steps with greater ankle and knee motion and increased tibialis anterior activity.”Remember we are talking about kids here. Longer steps because with a shoe we promote heel rocker and because of the added support, more stability (or at least more perceived stability). This means more confidence. Greater knee and ankle motion because of the increased stride length. Greater tibialis anterior activity because of greater dorsiflexion of the foot because of the increased weight (the shoe adds ounces and this muscle must work harder to attenuate the foot as it approached midstance) and increased heel and ankle rocker.

Shoes reduce foot motion and increase the support phases of the gait cycle.” Shoes constrain the foot and reduce available ranges of motion (yes, even non motion control shoes). Less motion (and thus proprioception) means less feedback to the brain about muscles length and tension (via muscle spindles and golgi tendon organs). The brain will need to have the foot have more contact with the ground to know where it is in space. 

“During running, shoes reduce swing phase leg speed,probably due to the increased weight so it takes more to start the process of initial (early) swing

attenuate some shock we know shoes attenuate at least initial ground reactive forces

…and encourage a rearfoot strike pattern.” most likely due to the cushioning (remember from the recent Kenyan study about barefoot heel strikers? (click here if you need a reminder) They were more likely to heel strike on softer surfaces) AND the increased stride length (which would require more ankle dorsiflexion). 

Wow. Shoes really do make the, er….kid.

The Gait Guys. Making it real and increasing your shoe and gait IQ with each post.                                                                                 

J Foot Ankle Res. 2011 Jan 18;4:3. doi: 10.1186/1757-1146-4-3.

Effect of children’s shoes on gait: a systematic review and meta-analysis.

Source

Discipline of Exercise and Sports Science, Faculty of Health Sciences, The University of Sydney, Cumberland Campus, PO Box 170, Lidcombe, 1825, NSW, Australia. cweg6974@uni.sydney.edu.au.

Abstract

BACKGROUND:

The effect of footwear on the gait of children is poorly understood. This systematic review synthesises the evidence of the biomechanical effects of shoes on children during walking and running.

METHODS:

Study inclusion criteria were: barefoot and shod conditions; healthy children aged ≤ 16 years; sample size of n > 1. Novelty footwear was excluded. Studies were located by online database-searching, hand-searching and contact with experts. Two authors selected studies and assessed study methodology using the Quality Index. Meta-analysis of continuous variables for homogeneous studies was undertaken using the inverse variance approach. Significance level was set at P < 0.05. Heterogeneity was measured by I2. Where I2 > 25%, a random-effects model analysis was used and where I2 < 25%, a fixed-effects model was used.

RESULTS:

Eleven studies were included. Sample size ranged from 4-898. Median Quality Index was 20/32 (range 11-27). Five studies randomised shoe order, six studies standardised footwear. Shod walking increased: velocity, step length, step time, base of support, double-support time, stance time, time to toe-off, sagittal tibia-rearfoot range of motion (ROM), sagittal tibia-foot ROM, ankle max-plantarflexion, Ankle ROM, foot lift to max-plantarflexion, ‘subtalar’ rotation ROM, knee sagittal ROM and tibialis anterior activity. Shod walking decreased: cadence, single-support time, ankle max-dorsiflexion, ankle at foot-lift, hallux ROM, arch length change, foot torsion, forefoot supination, forefoot width and midfoot ROM in all planes. Shod running decreased: long axis maximum tibial-acceleration, shock-wave transmission as a ratio of maximum tibial-acceleration, ankle plantarflexion at foot strike, knee angular velocity and tibial swing velocity. No variables increased during shod running.

CONCLUSIONS:

Shoes affect the gait of children. With shoes, children walk faster by taking longer steps with greater ankle and knee motion and increased tibialis anterior activity. Shoes reduce foot motion and increase the support phases of the gait cycle. During running, shoes reduce swing phase leg speed, attenuate some shock and encourage a rearfoot strike pattern. The long-term effect of these changes on growth and development are currently unknown. The impact of footwear on gait should be considered when assessing the paediatric patient and evaluating the effect of shoe or in-shoe interventions.

http://www.ncbi.nlm.nih.gov/pubmed/21244647

all material copyright 2013 The Gait Guys/ The Homunculus Group. All rights reserved. Yea, that means ask before you touch!