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.

The debate continues. More support for mid and forefoot strikers.

“Forefoot and midfoot strikers had significantly shorter ground contact times than heel strikers. Forefoot and midfoot strikers had significantly faster average race speed than heel strikers.”

We are not saying “better”, but according to this study “faster”!

What is the ideal?  We wish we knew…Biomechanics seem to point to less impact is better, but what is actually best for the individual is probably due to genetics, training, practice, running surface and that individuals neuromuscular competence and ability to compensate.

The Gait Guys. bringing you the facts, even if you or we don’t like them…

                                                                                                                                     

J Sports Sci. 2012;30(12):1275-83. doi: 10.1080/02640414.2012.707326. Epub 2012 Aug 2.

Foot strike patterns and ground contact times during high-calibre middle-distance races.

Source

Department of Sport and Exercise Sciences, School of Life Sciences, Northumbria University, Newcastle-upon-Tyne NE1 8ST, UK. phil.hayes@northumbria.ac.uk

Abstract

The aims of this study were to examine ground contact characteristics, their relationship with race performance, and the time course of any changes in ground contact time during competitive 800 m and 1500 m races. Twenty-two seeded, single-sex middle-distance races totaling 181 runners were filmed at a competitive athletics meeting. Races were filmed at 100 Hz. Ground contact time was recorded one step for each athlete, on each lap of their race. Forefoot and midfoot strikers had significantly shorter ground contact times than heel strikers. Forefoot and midfoot strikers had significantly faster average race speed than heel strikers. There were strong large correlations between ground contact time and average race speed for the women’s events and men’s 1500 m (r = -0.521 to -0.623; P < 0.05), whereas the men’s 800 m displayed only a moderate relationship (r = -0.361; P = 0.002). For each event, ground contact time for the first lap was significantly shorter than for the last lap, which might reflect runners becoming fatigued.

PMID:22857152[PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/22857152

Support for a midfoot strike?

Running with a midfoot strike pattern resulted in a significant increase in gastrocnemius lateralis pre-activation (208 ± 97.4 %, P < 0.05) and in a significant decrease in tibialis anterior EMG activity (56.2 ± 15.5 %, P < 0.05) averaged over the entire stride cycle. The acute attenuation of foot-ground impact seems to be mostly related to the use of a midfoot strike pattern and to a higher pre-activation of the gastrocnemius lateralis. “

Do these results surprise you? They didn’t really surprise us.

The lateral head of the gastroc is a midstance to preswing stabilizer and works synergistic with the medial head, with the medial head firing earlier. Sutherland talks about these muscles not being propulsive in nature, but rather maintainers of forward progression, step length and gait symmetry. Thinking this through in a closed chain (foot up) fashion, this would counter the inversion moment created by the medial gastroc for supination in the second half of contact phase. If the foot is already partially supinated (as we believe it would be in a midfoot strike), it would have to pre activate.

A decrease in tibialis anterior activity? Sure. If the foot is striking more parallel to the ground, the anterior compartment (including the tibialis anterior, extensor hallucis longus, and extensor digitorum longus) would not have to eccentrically contract to decelerate the lowering of the foot to the ground.

Better? Maybe, maybe not. We are seeing more and more literature about foot strike (if you missed our last few posts, click here, here, here and here), We still maintain that you need a competent lower kinetic chain, including the foot and an intact nervous system to drive the boat.

We remain, handsome, bald and nerdy…Ivo and Shawn

                                                                                                                                

Eur J Appl Physiol. 2012 Aug 9. [Epub ahead of print]

Impact reduction during running: efficiency of simple acute interventions in recreational runners.

Source

University of Lyon, 42023, Saint-Etienne, France.

Abstract

Running-related stress fractures have been associated with the overall impact intensity, which has recently been described through the loading rate (LR). Our purpose was to evaluate the effects of four acute interventions with specific focus on LR: wearing racing shoes (RACE), increasing step frequency by 10 % (FREQ), adopting a midfoot strike pattern (MIDFOOT) and combining these three interventions (COMBI). Nine rearfoot-strike subjects performed five 5-min trials during which running kinetics, kinematics and spring-mass behavior were measured for ten consecutive steps on an instrumented treadmill. Electromyographic activity of gastrocnemius lateralis, tibialis anterior, biceps femoris and vastus lateralis muscles was quantified over different phases of the stride cycle. LR was significantly and similarly reduced in MIDFOOT (37.4 ± 7.20 BW s(-1), -56.9 ± 50.0 %) and COMBI (36.8 ± 7.15 BW s(-1), -55.6 ± 29.2 %) conditions compared to NORM (56.3 ± 11.5 BW s(-1), both P < 0.001). RACE (51.1 ± 9.81 BW s(-1)) and FREQ (52.7 ± 11.0 BW s(-1)) conditions had no significant effects on LR. Running with a midfoot strike pattern resulted in a significant increase in gastrocnemius lateralis pre-activation (208 ± 97.4 %, P < 0.05) and in a significant decrease in tibialis anterior EMG activity (56.2 ± 15.5 %, P < 0.05) averaged over the entire stride cycle. The acute attenuation of foot-ground impact seems to be mostly related to the use of a midfoot strike pattern and to a higher pre-activation of the gastrocnemius lateralis. Further studies are needed to test these results in prolonged running exercises and in the long term.

PMID:22875194 [PubMed – as supplied by publisher]


All material copyright 2013 The Gait Guys/The Homunculus Group, yada, yada, yada…

Looks like Newbies are heel strikers

“Nearly all novice runners utilize a rearfoot strike when taking up running in a conventional running shoe. Hereby, the footstrike patterns among novice runners deviate from footstrike patterns among elite and sub-elite runners.”


please take some time to explore the links we put in, as they are germane to the post


The question begs, “Why?”

  • do they believe running is merely an extension of walking, and just “speed up” the process?
  • are they afraid of going too fast and are using the heel strike to “brake”?
  • do they learn to strike differently with more experience? at least one paper eludes to “yes”
  • is it “more comfortable” as this paper says it may be?
  • If there is a rear foot strike, the foot is poised to be able to pronate to a greater degree. This theoretically means it (ie, the foot) can absorb more shock through this mechanism, although this seemingly contradicts the Lieberman study

This paper certainly had a nice cohort size (> 900 runners) so we can state, at least for this group, that this is not by chance.  When there is a fore foot strike, the foot is more supinated and makes a seemingly “rigid lever”, does this mean there is less shock (perceived or actual) with this foot posture?

Lots of questions. This is only 1 part of the puzzle.

The Gait Guys. Sifting through the literature and giving you the beef

            

Gait Posture. 2012 Dec 29. pii: S0966-6362(12)00448-1. doi: 10.1016/j.gaitpost.2012.11.022. [Epub ahead of print]

Footstrike patterns among novice runners wearing a conventional, neutral running shoe.

Bertelsen ML, Jensen JF, Nielsen MH, Nielsen RO, Rasmussen S.

Aarhus University Hospital, Aalborg Hospital, Orthopaedic Surgery Research Unit, Science and Innovation Center, Aalborg DK-9000, Denmark. Electronic address: miclejber@gmail.com.

Abstract

INTRODUCTION:

It has been suggested that striking on the midfoot or forefoot, rather than the rearfoot, may lessen injury risk in the feet and lower limb. In previous studies, a disparity in distribution in footstrike patterns was found among elite-, sub-elite, and recreational runners.

PURPOSE:

The purpose of this study was to investigate the footstrike patterns among novice runners.

METHODS:

All runners were equipped with the same conventional running shoe. Participants were video filmed at 300 frames per second and the footstrike patterns were evaluated by two observers. The footstrike was classified as rearfoot, midfoot, forefoot, or asymmetrical.

RESULTS:

A total of 903 persons were evaluated. The percentages of rearfoot-, midfoot-, forefoot-, and asymmetrical footstrike among men were 96.9%, 0.4%, 0.9%, and 1.8%, respectively. Among women the percentages were 99.3%, 0%, 0%, and 0.7%, respectively.

CONCLUSION:

Nearly all novice runners utilize a rearfoot strike when taking up running in a conventional running shoe. Hereby, the footstrike patterns among novice runners deviate from footstrike patterns among elite and sub-elite runners.

Copyright © 2012 Elsevier B.V. All rights reserved.

PMID: 23280125 [PubMed – as supplied by publisher]



all material copyright 2013 The Gait Guys/The Homunculus group. Please don’t lift our stuff without asking and giving credit.

New Study Finds Group of Heel Striking Barefoot Kenyan Runners.

Not all that is barefoot is necessarily forefoot…

You may have seen our tweet yesterday and have read this article. Or maybe, because you are a foot geek, you have seen it already.

Here’s the summary: “Jan. 9, 2013 — A recently published paper by two George Washington University researchers shows that the running foot strike patterns vary among habitually barefoot people in Kenya due to speed and other factors such as running habits and the hardness of the ground. These results are counter to the belief that barefoot people prefer one specific style of running.”

The study reported a 72 percent rearfoot landing when running barefoot at endurance pace speeds supporting the notion that speed affects landing choice (faster speeds transitioned  the runners into more midfoot / forefoot landing).  Lieberman’s Harvard study which brought much of the forefoot strike principle to the western world was often based off of sub 5 mile paced runs.

It raises the question ” If barefoot IS better, and forefoot impact IS BETTER, then, what gives?”

We think the better response is:

  • there are many variables (genetics, surface, speed, etc) that can influence foot strike patterns and this paper exemplifies that.
  • Fore foot striking in runners does lessen impact forces.
  • Forefoot striking does appear to accentuate any forefoot abnormality (ie: varus/valgus) that may be present (something we will continue to say until someone proves it otherwise).
  • forefoot striking loads the posterior compartment of the lower leg (tricep surae (gastroc soleus complex)) to a greater degree

We like a mid foot strike, not because it is the middle road, but because it supports the notion in distance running that the entire foot tripod (which is more stable) engages the ground reducing solitary forefoot and rearfoot loading issues which each have their risks and challenges and allows for a more stable contact point for the body to negotiate over.  We have pounded sand on forefoot types, and the inherent risks of forefoot strike running with each of them, from our inception.  But, when it comes to midfoot strike there doesn’t appear to be much, if any literature out there to support our opinion.  Maybe now that the forefoot and rearfoot studies are out there maybe someone will find a tribe of midfoot strikers to support our rants.

We think the key is not necessarily strike position, but rather where the foot is hitting the ground relative to the body AND MORE IMPORTANTLY, having a competent foot and lower kinetic chain and core, along with the body’s ABILITY to absorb or attenuate those forces, no matter where the foot is striking the ground.

This is no doubt the 1st in a series of papers looking at this. It will be interesting to see where it goes from here.

Ivo and Shawn…  The Gait Guys

here is the link: http://www.sciencedaily.com/releases/2013/01/130109185856.htm

all material copyright 2013 The Homunculus Group/ The Gait Guys. Please ask to use our stuff and reference it appropriately. We know a guy named BamBam who helps people play nice.