(NEW YORK) -- A new lawsuit alleges that Skecher's Shape-up shoes can cause serious injuries.
An Ohio woman is suing the company after developing stress fractures in both hips -- which she blames on the shoes.
Skecher's Shape-ups have a distinctive round sole. They are marketed as toning shoes, the fastest-growing segment of the athletic shoe market. Toning shoes are meant to help you get in shape as you walk or work. But at least one person says rather than helping them, the shoes hurt them.
Holly Ward, 38, says her routine involves physical therapy and she has pins in her hips. She blames Skechers Shape-ups for her injuries.
Shape-ups are advertised as helping you get in shape and helping reduce pain. Kim Kardashian and former NFL quarterback Joe Montana have appeared in commercials for Shape-ups.
Ward says she wore the shoes during her work as a waitress and while on walks and developed severe pain after five months. According to her lawsuit, she had fractures in both hips near where they meet the thigh bones even though she has the healthy bone density of a young woman.
"The femoral bone is the strongest bone in the human body and I fractured not one but two of them without being in a car crash or any traumatic incident," she told ABC News.
ABC spoke to half a dozen orthopedists and most were skeptical that shoes alone could cause stress fractures.
Skechers told ABC that "since this lawsuit is brand new, we have not had an opportunity to review Ms. Ward's allegations and millions of people wear Shape-ups without experiencing what Ms. Ward alleges."
Copyright 2011 ABC News Radio