It has long been known that significant hip deformity resulting from childhood conditions such as developmental dysplasia of the hip and Legg-Calvé-Perthes disease can lead to secondary hip osteoarthritis in adult life. Over the past two decades, more subtle deformity of the hip has been implicated in the development of osteoarthritis in patients who previously were thought to have “primary osteoarthritis” of the hip. Primary or idiopathic osteoarthritis of the hip attributes arthritic progression to the effect of age-related chemical and mechanical deterioration of hip articular cartilage present in a subset of individuals for unknown reasons. Many patients who would formerly have been thought to fall within this primary group are now believed to have had hip impingement leading to osteoarthritis over time.
