The York University Magazine

Fall 2015

The alumni magazine of York University

Issue link:

Contents of this Issue


Page 6 of 47

I T 'S A LWAYS G O O D TO find drug-free solutions to the myriad of problems associated with general health and aging. York University PhD candi- date Brian Street and his colleagues have found a surprising antidote that could help slow the pro- gression of osteoarthritis – in some cases, even delaying the need for surgery. And it doesn't require a prescription. Knee osteoarthritis, which is usually very painful and can decrease quality of life, affects roughly one in five adults over age 45. The York study comprised 15 healthy male participants. Their strides were analyzed using special cameras and sensors that measure the forces developed in the joints of our legs as we walk. These state-of-the-art tools gave Street a unique 3-D perspective of each participant's movements as they demon- strated three different gait conditions: regular, toe-out and narrow (that is, narrower than normal). A complete move- ment picture was captured, for both the "dominant" limbs, favoured for propulsion, and the non-dominant, stabilizing limbs. The study's results showed that the narrow gait significantly reduced the early stance phase external knee adduction moment (EKAM), which occurs just as our foot first hits the ground, by approximately 50 per cent. EKAM is the move- ment of the upper portion of the leg relative to the lower portion. The EKAM causes the lower portion of the leg to be pulled inward, creating a kind of bow-legged position, resulting in forces created during walking to be concentrated on the inner portion of the knee – not good if you suffer from knee osteoarthritis. Knee surgery has been shown to reduce EKAM by 30 to 40 per cent compared to narrow gait's 50 per cent. However, Street notes that while narrow gait may be suitable for some people, it can also increase the risk of falling for other individ- uals. Bottom line? "Narrow gait may work, but people should use it judiciously." l F LU O R I D E. I T 'S I N O U R TO OT H PA S T E. It's applied to our teeth during regular dental checkups. And, sometimes, it's added to our tap water. About 30 per cent of Canadians receive fluoride through their public water supply. We think it benign, but how safe is it? Although fluoride can be found naturally in the environ- ment, most of what is in our tap water is the artificial form – a byproduct of fertilizer production, derived from one of three chemicals: hydrofluorosilicic acid (the most common), sodium fluorosilicate and sodium fluoride. Recent studies, including one by York University clinical psychology PhD candidate Ashley Malin and psychology Professor Christine Till, are uncovering a number of possible health problems with fluoride use. The York researchers looked at the potential link between fluoridation in the United States public water supply and increasing rates of attention deficit hyperactivity disorder (ADHD). They found that as the percentage of fluoridated public drinking water increased, so too did rates of ADHD in children aged four to 17. "Our findings showed that artificial fluoridation prevalence in 1992 predicted ADHD prevalence in 2003, 2007 and 2011 among children and adolescents in the United States," says Malin. This research raises huge questions, says Till. "We should be asking whether it is safe for many cities in Canada, including Toronto, to continue to fluoridate the water we consume." l Does adding fluoride put you at risk? Something in the Water Fall 2015 The York University Magazine 7 PHOTOGRAPHY BY MCKENZIE JAMES

Articles in this issue

Archives of this issue

view archives of The York University Magazine - Fall 2015