Smith-Petersen nail [Marius N. Smith-Petersen, American surgeon, 1886–1953; AS, naegel, nail] , a three-flanged, stainless steel nail used in orthopedic surgery to anchor the neck of the femur to its head in the repair of an intertrochanteric fracture. It is introduced below the prominence of the greater trochanter and passed through the fractured part into the head of the femur. See also nail, pin.