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Are there any physiotherapists reading this? I’d appreciate hearing from them as well of course from the ST community. One of my students (56 yrs old) has revealed that she has knee osteoarthritis (confirmed by MRI scans) in the medial cartilages of both knees. This is clearly a concern, because of the considerable chance that it will progress and she will end up needing knee replacements. Not only are knee replacements painful, but they only last about 15 years and a further operation (by which time the patient is usually very elderly) is problematic. Because 90% of knee replacements are to the medial bearing surface in the knee, unless this cartilage has some intrinsic weakness (and there is no evidence for this), then it suggests that some of the load in walking has not been shared properly between the medial and lateral cartilages, and that the medial cartilage has taken most of the load. Therefore it has an origin in faulty biomechanics (from the reviews I have found, this seems to be the generally accepted view). Faulty biomechanics could include faulty use of the leg muscles, faulty tracking of the knee joint in walking, faulty alignment of the foot (e.g rolling out, attempts to correct pronation), etc. If faulty biomechanics causes a problem that can escalate to catastrophic levels, it seems to me that it correct biomechanics should be introduced as early as possible, and preferably used all ones life – and that it should be taught routinely. This is what I attempt to do with a yoga standing exercise (of which more later). It is interesting that in my searches on the internet, there seems very little discussion of the importance of correct biomechanics in relation to this issue, how correct biomechanics are trained, and how they may be important in preventing knee osteoarthritis. Most of the attention seems devoted to dealing with patients who already have substantial knee osteoarthritis. One of the few reviews I have found is the following: Reeves ND, Bowling FL. (2011) “Conservative biomechanical strategies for knee osteoarthritis.” Nat Rev Rheumatol. 7(2):113-22. This needs a paid-for subscription, and the abstract from Pubmed is attached at the end of this message for anyone who wants to read it. As far as I can tell, this is an influential review, and many other sources on the web seem to copy its arguments (even if they don’t cite it). Reeves and Bowling say that the main danger is that the knee joint “bows out” to the side in walking (this is also known as knee varus or knee adduction). In the midphase of the stride the weight is in the midline of the body, but the weight is taken only on one leg which is not in line with the direction that the weight is acting. If incorrect muscle action is used, the knee may bow out to the side, meaning that most of the weight is taken on the medial cartilage, which wears (see attached diagram). Apart from using prostheses etc, the main strategy seems to be strengthening of the leg muscles to stop it getting worse. (the third diagram shows what leads to excessive force on the medial cartilage; in each case, the centre line of the body is to the right of each diagram) If you think what the leg muscles have to do to keep the weight directed along the line of the leg during all phases of the stride it is in fact a very complicated process, and I doubt if one could explicitly describe and learn it as such. What I do in my yoga standing exercise is to encourage muscle awareness of what happens when the muscles of the leg are all lightly but evenly engaged, and that one can “feel” the ground and the weight of the body traversing the length of the leg to all parts of the foot. The encouragement is not to use minimum awareness and not to let the leg muscles get lazy (which might lead to some muscles switching off). It seems to me that this is a very important issue and I am surprised that I have not been able to find any more resources on it. I have adapted a yoga exercise to deal with what is potentially a major medical problem. I need to know if I am using the best approach. As for my student, the physio she had earlier who diagnosed the osteoarthritis did not suggest any corrective action, so I presume this physio’s approach would be to leave her alone and let whatever started the process off continue until it crippled her. I have instead suggested that she should go to the most experienced and wisest physio I know. I hope that correct biomechanical training will reduce the load on the medial cartilage and stop any progression of the osteoarthritis. So my question is: what are the best exercises for normal people who do not yet show any signs of knee osteoarthritis, to ensure that they use the best biomechanics in walking, and have the minimum chance of developing knee osteoarthritis? Is a yoga standing exercise the best approach? (I can describe this if anyone wants to know the detail, but it is pretty standard, and this posting is already very long). Thanks for your help, Jim. Abstract of the paper referred to: Knee osteoarthritis (OA) is one of the most prevalent forms of this disease, with the medial compartment most commonly affected. The direction of external forces and limb orientation during walking results in an adduction moment that acts around the knee, and this parameter is regarded as a surrogate measure of medial knee compression. The knee adduction moment is intimately linked with the development and progression of knee OA and is, therefore, a target for conservative biomechanical intervention strategies, which are the focus of this Review. We examine the evidence for walking barefoot and the use of lateral wedge insoles and thin-soled, flexible shoes to reduce the knee adduction moment in patients with OA. We review strategies that directly affect the gait, such as walking with the foot externally rotated ('toe-out gait'), using a cane, lateral trunk sway and gait retraining. Valgus knee braces and muscle strengthening are also discussed for their effect upon reducing the knee adduction moment.