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Daryl, I find your clinical success interesting, and your supporting excerpts enlightening, but can't help thinking that the alteration of loading on different fibre bundles is the reason for your outcomes. This is akin to changing the alignment of a tyre on your car to remove pressure from one worn area, to place pressure on another area, which in turn, in time, will become worn. The body has a huge ability to compensate for changes, and your patient's feet will certainly appreciate the change. I hope, but doubt, that the reduction in pain will be permanent, unless the frontal plane deformities are addressed. I refer you to a chapter in "the Biomechanics of the Foot and Ankle", by Bob Donatelli, entitled "Biomechanical Orthotics", in particular .." supporting the forefoot abnormalities reduces the need for rearfoot compensation. For example, forefoot varus is compensated for by rearfoot subtalar joint pronation. Forefoot varus, by itself, is not destructive to the foot. However, at the subtalar joint compensatory pronation results in an "unlocking' of the foot, creating hypermobility and loss of a rigid lever from midstance through push-off. " Forefoot varus is addressed using a medial wedge on the forefoot. I have made up to 200 pairs of biomechanical orthotics over the last nine years, with excellent, although not infallible success at longterm pain reduction. Martin ---------- > From: ashlini and daryl <[log in to unmask]> > To: [log in to unmask] > Subject: Re: taping for plantar fasciitis > Date: Tuesday, 21 March 2000 07:19 > > Martin Kidd wrote: > >It follows that anything that causes excess pronation, such as a > > lateral forefoot post, would be detrimental to foot stability. > > Martin Kidd. > > I disagree. The wedging acts on the MTJ, not the STJ and aims to evert the > MTJ axis to prevent the dorsiflexion moment caused by XS pronation or > conversely by inducing a plantarflexory moment. Having now used these in a > clinical situation I find improved results from a treatment perspective with > valgus wedging at the forefoot. Following are few things that may help. > > *To quote someone far more intelligent than myself: > Eric Fuller has written, > "Arch flattening is caused by a plantar flexion moment on the forefoot or a > dorsiflexion moment on the forefoot. So, we need to analyze the foot and > figure out what structures could cause a plantarflexion moment on the > forefoot or a dorsiflexion moment at the rearfoot at the level of the MTJ. > (MTJ is an arbitrary divider of forefoot and rearfoot.) Tension in all the > slips of the plantar fascia, the plantar calcaneocuboid ligaments, the > spring ligament and a few muscles combined with compression at the joint > surfaces can prevent > dorsiflexion of the forefoot. There is redundancy, that is to say that the > load may or may not be shared across all of those structures. For example, > the medial slip of the plantar fascia may have 70% of the load and the > plantar calcaneo cuboid ligament may have 30% of the load in one situation. > A forefoot valgus wedge may cause a shift in the load from the medial slip > in the plantar fascia to the plantar calcaneo cuboid ligaments. The total > load remains essentially the same (body weight) but the structures that > support the load change. Less load in the medial slip of the plantar fascia > = less pain. I believe the 'locking the MTJ' (maximal eversion of the LMTJ) > puts more load in the lateral plantar ligaments." > > *Kogler GF, Solomonidis SE, Paul JP (1998)The influence of medial and > lateral wedges on the loading of the plantar aponeurosis. Proceedings from > the IXth World Congress of the International Society of Prosthetics and > Orthotics. Amsterdam: International Society of Prosthetics and Orthotics. > "......An in vitro method that simulated "static" stance was used to > determine the loading characteristics of the plantar aponeurosis. Nine test > conditions were evaluated with eight different wedge (6degrees) > combinations and a level plane serving as the control. Each of the forefoot > wedge treatment groups was statistically distinct compared to the neutral > control, with lateral forefoot wedges decreasing the strain in the plantar > aponeurosis and the medial forefoot wedges increasing strain (p<0.05). The > rearfoot wedge conditions that did not combine the use of a forefoot wedge > were not statistically different from the control (p.0.05)" > > *There was also a presentation at the Aust Pod Conference in 98 (and I think > a few subsequent times)comparing valgus forefoot wedges to meidal wedges, > FO, etc and it suggested that valgus wedging was the more effective. > > Hope this clarifies a few things, > Daryl > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%