I found this one AOL today. I've had my suspicions about these but figured my observations were flawed owing to my personal experience - and having existing hip and arch issues. But evidently, this is a universal problem. I had recently changed to Chaco shoes (including their strap version) and turns out that was a good move! They even have the American Podiatric Medicine Association's Seal of Acceptance. (sidenote - www.endless.com ships FREE - and OVERNIGHT - and even better has FREE RETURN SHIPPING!...I won't even go into their 110% lowest price guarantee...)
Style Number: 3724
Anyway, for what it's worth, and for the love of all things summer and flip-flops, read this and "tread" with caution!