title: Femoroacetabular impingement.
abstract: Femoroacetabular impingement is a relatively recently appreciated "idiopathic" cause of hip pain and degenerative change. Two types of impingement have been described. The first, cam impingement, is the result of an abnormal morphology of the proximal femur, typically at the femoral head-neck junction. Cam impingement is most common in young athletic males. The second, pincer impingement, is the result of an abnormal morphology or orientation of the acetabulum. Pincer impingement is most common in middle-aged women. This article reviews the imaging findings of cam and pincer type femoroacetabular impingement. Recognition of these entities will help in the selection of the appropriate treatment with the goal of decreasing the likelihood of early degenerative change of the hip.
authors.affiliation: Department of Radiology, Division of Musculoskeletal Radiology, Massachusetts General Hospital, Boston, MA, USA. akassarjian@partners.org
authors.forename: Ara
authors.initials: A
authors.lastname: Kassarjian
authors.forename: Mélanie
authors.initials: M
authors.lastname: Brisson
authors.forename: William E
authors.initials: WE
authors.lastname: Palmer
mesh_terms: D000077:Acetabulum / Q000473:pathology* / Q000601:surgery; D001175:Arthrography / Q000379:methods; D005260:Female; D005270:Femur Head / Q000473:pathology* / Q000601:surgery; D006621:Hip Joint / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007592:Joint Diseases / Q000175:diagnosis* / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010146:Pain / Q000209:etiology