Shoes with high heels are the fashion [choice / choose] for many women around the world. However, a new study [provides / proves] that wearing high heels over a long period [for / of] time can permanently [injury / injure] the body. The study is from Stanford University in the USA. A team of biomotion researchers did tests [in / on] the knees of women when they walked in flat shoes, shoes with 3.8-cm heels and in shoes with 8.9-cm heels. The results [send / sending] a warning to women who want to wear high heels that they risk permanent damage [to / from] their knees. They said high heels put knees in an awkward, [bend / bent] position that makes them function like aged or damaged [joint / joints] . This increases the risk of the condition osteoarthritis, which could [require / requirement] surgery. Britain's Daily Express newspaper reports a [recent / recently] survey of 1,200 women that shows how [popularly / popular] high heels are. It said 93 per cent of women say they felt sexier and more [feminist / feminine] when they wore heels, 88 per cent said they considered themselves more [style / stylish] and 77 per cent said their heels made them [feeling / feel] slimmer. Many women prefer to [ignore / ignoring] health warnings, and even the pain and discomfort of wearing heels, to look and feel good. A British doctor, Tim Allardyce, said he [frequent / regularly] treats women with problems caused by wearing heels. He said: "The [odd / oddly] angle at which the feet are held in high-heeled shoes increases the downward [pressurise / pressure] on the knees by 25 per cent, placing [significant / significantly] stress on the kneecaps."