Abstract: An anatomic prosthetic femoral implant system has a series of modular part-spherical heads and between 4 and 8 femoral component size groups. Each size group has only four components, two left and two right hip implants. One right and one left component being neutral in version and one right and one left being anteverted at an angle producing a head offset of between 4 and 5 mm from neutral. The head offset remains in this 4-5 mm range through all the size groups in the system. It has been found that a large proportion of the target patient population can be served by such a system.

Abstract: A prosthetic femoral implant has a stem having a proximal end and a distal end. A circumferential collar is formed on the proximal end of the stem having a proximally facing surface in the form of a circular disc extending radially inwardly and proximally from a maximum outer circumference to a central neck region. The collar has a distally facing surface extending radially inwardly and distally at an included angle with respect to a central longitudinal axis of the neck region of between 120 and 140°. The distal surface of the collar is v-shaped and may be conical in form.

Abstract: A prosthetic femoral implant has a stem having a proximal end and a distal end. A circumferential collar is formed on the proximal end of the stem having a proximally facing surface in the form of a circular disc extending radially inwardly and proximally from a maximum outer circumference to a central neck region. The collar has a distally facing surface extending radially inwardly and distally at an included angle with respect to a central longitudinal axis of the neck region of between 120 and 140°. The distal surface of the collar is v-shaped and may be conical in form.