Hi all. I'm a 1st yr PT student working on a research project. The catch is that it has to be BIOMECHANICAL in nature. The goal is do some background/significance of topic work, then develop a research question that we would like to answer and the methods necessary to answer it. My wife had some female athlete triad issues in college and when I mentioned that to my prof, he suggested that I look into the increased incidence of stress fractures in amenorrheic female runners. We refined that idea a bit to include the decreased bone mass aspect (somewhat biomechanical) associated w/ both amenorrhea and stress fractures. However, as I read through the research, I'm having a difficult time coming up with any sort of research question on that topic - at least one that would involve the manipulation of any variable(s). There doesn't seem to be much that's debatable: amenorrhea leads to hypoestrogenic decreased bone density; decreased bone density leads to stress fractures (assuming a unchanged load)...ergo, amenorrhea leads to stress fractures. Where's the biomechanics? To me, it's more of a metabolic/physiologic research area. So, I'm wondering, am I missing something here, or do I go back to my prof and suggest going a different direction with stress fractures, say the degree of pronation/supination in propulsion and it's relationship. Any thoughts?
Joined: March 15, 2006
I agree with you that it sounds less biomechanical than physiological although, if there is movement, there are biomechanics involved. That said, I would rather have someone prove or disprove something that I think is true.
Clinical question: Does the structure of the foot or the control of the structure of the foot lead to stress fractures? Maybe you could word it better but I propose that someone with flat feet is not as likely to get stress fractures as someone with poor balance (i.e. control over their foot position) all other things being equal.
It might be a longer term study than you have time for but if you are in a place where you have a large enough sample of people with diagnosed stress reactions, you could have them randomized into orthotic groups and balance training group and orthotic with balance group.
I suspect that really bad feet make for a higher liklihood of stress fractures but good feet with bad balance is worse. bad feet with bad balance is very destructive and likely would make the person not like physical activity in the first place and they may exclude themselves by not running/walking etc . . so they don't ever develop the stress reaction in the first place.
Joined: February 14, 2003
From: Madison WI USA
and/Or, could you make an argument for studying the same runners on a grassy, more cushioned surface than the typical pavement pounders? maybe you just reproduce the other study on a different surface? It could be ground breaking.....pardon the pun.
Joined: May 11, 2004
Alex Brenner presented the results of his work - he was trying to create a clinical prediction rule for male soldiers that would have a high likelihood of stress fracture. Seemed as though certain performance test measures were more able to predict the incidence of stress fracture than the foot biomechanics.
These are all good ideas. Thanks! I believe we've moved in a direction that is leading us to investigate the effects on BMD/stress fractures of impact loading sports vs. active loading sports in amenorrheic women. My challenge is that I can't find anything that accurately defines impact loading vs. active loading. Most studies I've come across have volleyball/soccer/gymnastics as impact loading and swimming as the active loading sport. I did find one study that used long-distance running as the active loading sport. We want to compare amenorrheic runners (Active loading sport) vs. amenorrheic gymnasts (impact loading sport) and their BMD. As such, the study would seek to determine what a better predictor of stress facture would be: amenorrhea or type of loading (sport). I just need help on definitively categorizing/defining active vs. impact loading sports. Thanks,