Since then, the shoes have become available in 40 countries. The company currently manufactures about 4 million pairs of Crocs a month. And recently the shoes have been offered in their smallest size yet -- a 4/5 model for small children.
It is this smaller size that has some podiatrists concerned.
"It seems to be the smallest of children wearing them, so there seems to be a size issue. A small foot in a small Croc is going to be more easily caught in the teeth of the escalator and the side of the escalator," Volpe said. "They are also saying a big factor is that it's toddlers that are not standing still. If you plant your feet and stay away from those risk spots you are probably at lower risk of injury, but try and tell a 2-year-old that."
Alfieri agrees. "They're still learning how to walk," she said. "They may not be ready for that type of shoe, they need stability in their early gait development more than someone older."
The fact that Crocs is coming out with a winter line -- called You by Crocs -- has some worried that such injuries will become a year-round occurrence in colder climes.
Mattson notes, however, that these offerings will be a completely different type of footwear, as they will consist of a leather or suede upper combined with the flexible resin sole for which Crocs are widely known.
And despite the recent reports, Volpe said that the main issue when it comes to wearing Crocs -- a pair of which he himself owns and enjoys -- is knowing where and when to use them.
"I don't think that Crocs could do much to the shoe to change it," he said. "I think that it's more the judgment of those wearing them and exercising the place they choose to wear them."
Johnson adds that his daughter often still wears her Crocs -- the very pair in which she was injured. These days, however, escalators are off-limits as long as the shoes are on her feet.
And Johnson said that the pair of Crocs he wears have helped him move around more comfortably, as their soft construction helps him deal with his painful plantar fasciitis.
"I think they're great," he said. "But any kind of shoe like that with escalators is just a bad combo."
Dr. Susan Kansagra contributed to this report.