The Myopathic Gait:

This gait abnormality is sometimes referred to as a waddling gait. The waddle or shift is secondary to proximal pelvic musculature weaknesses.  The client may utilize a limb circumduction strategy to compensate for the weakness in the gluteals or as seen better here displaying an exaggerated alternation of lateral trunk movements with an exaggerated elevation of the hip.  There are some distinct similarities to the Trendelenburg gait pattern.  There are several causes of this gait variant, some of which are temporary and some of which are orthopedic and some neurodegenerative.  For example: pregnancy, hip dysplasia, muscular dystrophy and spinal muscular atrophy. 

Immediate effects of acupuncture on gait patterns in patients with knee osteoarthritis.

“while no significant changes were found in all the gait variables in the sham group, the experimental group had significant increases in the gait speed, step length, as well as in several components of the joint angles and moments.”

Immediate effects of acupuncture on gait patterns in patients with knee osteoarthritis.

Orthotic Shoe Inserts May Work, but It’s Not Clear Why

Leading orthotics researcher, professor of biomechanics@ Human Performance Lab @ Univ. of Calgary,Alberta. His conclusion: orthotics may be helpful as a short-term solution, preventing injuries in athletes. But it’s not clear how to make inserts that work. The idea that they are supposed to correct mechanical-alignment problems does not hold up. The work of THE GAIT GUYS, hopes to offer some insight.

Ivo Waerlop A potential riff in the article (Via Stu Currie):

1) Primates only have a transverse arch – they are flat in the longitudinal direction.

2) In primates the metatarsal bases are on the same plane as the metatarsal heads.

3) The length of the phalanges is 18% of total foot length in humans, and 35% in chimps.

4) Australopithecus afarensis (Lucy) has the beginning features of a longitudinal arch, while retaining many characteristics of the ape foot. The same can be said for other hominid ancestors (H. Habilus)See MoreJanuary 20 at 7:51am · LikeUnlike

Ivo Waerlop We have always said that orthotics serve as a therapy, not a solution. Your prescription should be getting better (lessening) or more correction taken out with time, not becoming greater. They are an excellent tool, but not a substitue for good mechanics.

Orthotic Shoe Inserts May Work, but It’s Not Clear Why

Same quality, less filling. Ever think about what happens to that old pair of running shoes you retired or gave to the dog? It takes about 1000 years (yes, that’s 3 zeroes) for the EVA ( the midsole material in most running shoes) to break down. Brooks has come up with a nice alternative, that under the right conditions , takes 50 times less or about 20 years. Brooks Trance 8: The First Biodegradable Running Shoe

The First Biodegradable Shoe

Peter Weyand, PhD, SMU. Locomotor Performance Laboratory.

From our new friend Peter Weyand, PhD, SMU, Dallas. Southern Methodist University, Locomotor Performance Laboratory.
In the study:
The biological limits to running speed are imposed from the ground up.
J. Appl Physiol (Jan 21, 2010).
Study concluded that the stance phase limit to running speed is imposed, not by the maximum forces that the limbs can apply to the ground, but rather by the minimum time needed to apply the large, mass-specific forces necessary. So, the faster the foot applies the max force into the ground and gets that foot off the ground to do the same on the other foot, the faster the person will be able to run.

Harvard: Lieberman Studies on heel strike

Lieberman: …most experienced, habitually barefoot runners avoid heel landing & instead land forefoot or midfoot strike….most FF & some MF strikes (shod or barefoot) do not generate the sudden, large impact transients that occur with heel strike (shod or barefoot). Consequently, FF or MF strikers do not need shoes with elevated cushioned heels to cope with sudden, high transient forces that occur when you impact.

Shoes and Cushioning

…and…Shoes with cushioning fail to absorb impact when humans run and jump, and amplify force under certain conditions, because soft materials used as interfaces between the foot and support surface elicit a predictable reduction in impact-moderating behavior. This behavior is not a response to sensations directly caused by impact because, ….
….whereas barefoot humans estimate impact precisely, humans judge it inaccurately when shod. Recent reports also indicate that humans reduce impact-moderating behavior, thereby amplifying impact, when they are convinced that they are well protected by the footwear they are wearing. …accounts for the 123% greater frequency of injuries with the most expensive shoes found by Marti.18

More fuel for the minimalistic Shoe trend….BioMechanics April 1998, “Materials: Do soft soles improve running shoes?”Most athletic shoes advertise injury protection through “cushioning,” but real world studies have not shown impact moderation.-By Steven Robbins, MD, Waked, Saad

Materials: Do soft soles improve running shoes?

Saucony Kinvara

(repeat posting from January2011)
Saucony has jumped on the minimalist running bandwagon with the Saucony Progrid Kinvara, a 7.7oz training shoe that has a heel-toe offset of only 4mm (heel height=18mm, forefoot height=14mm thus heel:forefoot ratio is 1.2  !). The upshot: with it’s relatively flat sole, its well suited to promote a midfoot/forefoot footstrike. IF your foot type is appropriate for the shoe ! Key point !

Rearfoot : Forefoot Slope Ratio

If you are like the Gait Guys you care about the heel:forefoot ratio of a shoe as the biomechanics change in the shoe. The closer you get the heel and forefoot to the same plane of contact the more natural the foot biomechanics. This is, in part, what the trend of the minimalistic / barefoot trend in shoes is all about. There are many other factors, but this is a big one.