| 摘要 |
The present invention provides an improved method and apparatus for preparin g a femur to receive a modular prosthetic femoral component. A distal reamer having a plurality of sets of depth marks is utilized to prepare the distal femoral canal. The sets of depth marks on the distal reamer correspond in number to the number of distal femoral stems available for use with the particular modular prosthetic femoral implant set. Each set of depth marks comprises a plurality of indicator rings corresponding in number to the numb er of proximal bodies adapted for utilization with the prosthetic femoral component set. Prior to distal reaming, the appropriate set of depth marks and indicator ring is chosen corresponding to the modular components the surgeon wishes to utilize. Reaming then takes place until the chosen indicator ring is aligned with a reference point (e.g., the top of th e greater trochanter). Upon reaching the appropriate reaming depth, the distal reamer is left in place in the femoral canal. A cannulated forming tool, e.g. a rasp or reamer, is thereafter positioned over the shank of the distal reamer and utilized to effect proximal canal sizing. The distal reamer head is sized whereby the proximal reamer, e.g., will abut the reaming head of th e distal reamer when the proximal reamer reaches the appropriate depth associated with the shortest distal stem of the modular femoral component set. In this way, the head of the dist al reamer provides a mechanical stop for the proximal reamer so that both under reamin g and over reaming are avoided. In cases in which a longer femoral stem is utilized, a cylindrical spacer having a length corresponding to the length difference between the shortest distal stem and the chosen distal stem is utilized to provide a mechanical stop for the proximal reamer. The reamer spacer includes an elongate aperture sized whereby the reamer spacer fits about the shank of the distal reamer.
|
