he extreme floppy and rigid feet

[Labi1995]

Bony structure of the medial longitudinal arch of the foot – navicular bone is located near the apex of the arch – Photo from Gray’s Anatomy via WikipediaThe functional navicular drop test sounds complex, but in reality is quite simple. The navicular is a bone in the midfoot near the apex of the medial arch, and the functional navicular drop test compares the Nike Air Max 98 Femme height of the navicular during relaxed seated (non-weight bearing) vs. relaxed standing (weight bearing) positions. Higher values for functional navicular drop would thus indicate a greater degree of arch deformation/collapse, and thus a floppier, more mobile foot. Lower values for functional navicular drop indicate a more rigid arch that does not compress much. The second static test – the static subtalar navicular drop test – compares navicular height when the foot is placed in “neutral” position to when the foot is allowed to relax and compress the arch.Results of Dicharry’s study (see below) showed that despite significant differences in arch collapse between the groups during static testing, arch collapse was identical in all three groups during walking, and the only difference observed during running was a small but significant Nike Internationalist Femme difference between the hypermobile and hypomobile groups, neither of which were significantly different from people categorized as neutral (i.e., only the extremes were different, and the magnitude of the difference was far smaller than would be found using the static measures). Furthermore, despite increase in force magnitude during running, only the hypermobile group exhibited greater arch compression during running as compared to walking. They suggest that neuromuscular control during dynamic movement could explain these differences – basically, the brain activates appropriate musculature in the foot and legs to manage the forces and maintain the arch during walking and running, and this is not captured by measuring the arch when we stand still. The basic message is that even if you have flat feet and your arches collapse Adidas Superstar Mujer when you stand still, your arch may behave very much like the foot of a normal arched person when you are walking or running, likely due to muscular control.This brings us to paper number three, which was just published on-line in Gait & Posture. The authors, led by Jesper Bencke from Copenhagen University Hospital in Denmark, compared measures of static navicular drop to both 2-D and 3-D measures of arch deformation during walking. They found only a moderate correlation www.anbilazio.it between static measures of the arch and those obtained during walking (r2 = 0.31 for you stats oriented folks), and conclude the following:“Assuming the foot as a two-segment structure in the sagittal plane with a hinge joint placed at the navicular bone between the forefoot and the hindfoot, the increased plantarflexor moment during push-off would correlate to Nike Air VaporMax Damen an external moment attempting to dorsiflex the forefoot with respect to the hindfoot. The lack of good correlation between static and dynamic measures could thus be a result of this extra load being counteracted differently between participants. This would further imply that a static test measuring the ND (navicular drop) might only have limited validity as predictor of MLAD (medial longitudinal arch deformation) during gait.”And these are not the only three papers that Nike Air Vapormax Dames have shown this – if you’d like to read the full text of one you can take a look at Deng et al., 2010, who found no relationship between navicular drop measurements and arch deformation measured during walking.So what does all of this mean? Basically, it tells us that what the arch looks like and how it deforms when we are standing or sitting probably doesn’t tell Nike Air Max 97 Femme us much about what the arch does when we are actually moving. Thus, applying the “wet footprint” test as a basis for determining foot type, and thus as a basis for choosing a running shoe makes very little sense. If you are in a shoe store and they suggest that you try this test or if they take a look at your arch while you are stationary, be very wary of any advice that you get (this probably applies to those fancy foot scanning machines as well). As Dicharry showed, www.matthieugranier.fr only the extreme floppy and rigid feet differed in degree of arch deformation during running, and the difference was very small and of unknown clinical significance (and neither differed from so-called “neutral” feet). What’s more, we have several studies showing that assigning shoes based upon arch height provides no benefit in terms of injury outcomes when compared Nike Air Max 270 Femme to simply assigning everybody a stability shoe regardless of foot type (see here and here for examples).