Method of using a measuring instrument in an orthopaedic surgical procedure

Abstract

A method of performing an orthopaedic surgical procedure. The method includes using a measuring instrument to size orthopaedic components.

1 . A method of performing an orthopaedic surgical procedure, comprising:
 resecting a proximal end of a patient's tibia to form a planar proximal surface,   resecting a distal end of a patient's femur to form a planar distal surface, the patient's femur including at least one posterior condyle,   inserting an intramedullary rod into an intramedullary cavity of the patient's femur,   locating a measurement structure on the intramedullary rod by positioning the end of the rod such that the measurement structure housing is pressed against the planar distal surface of the patient's femur,   drawing a plate member of the measurement structure upwardly to engage an upper face of the plate member with the at least one posterior condyle,   attaching a reference structure to the measurement structure to advance a tip of a stylus of the reference structure into contact with an anterior cortex of the patient's femur,   noting an indicated size of a femoral component using a first scale provided by the measurement structure and the reference structure,   attaching a mask to the reference structure and the measurement structure such that the femoral component size indicated on a scale portion of the reference structure is visible through one of a number of windows in the mask,   moving the plate member of the measurement structure downwardly to engage a lower face of the plate member with the planar proximal surface of the patient's tibia and place soft tissue extending between the patient's tibia and femur under appropriate tension,   noting an indicated size of a bearing component using a second scale of the measurement structure and the reference structure, and   inserting pins through the mask windows and into corresponding holes of reference structure to provide location for a cutting block.   
     
     
         2 . The method of  claim 1 , wherein noting the indicated size of the femoral component using the first scale provided by the measurement structure and the reference structure includes:
 identifying a single indicium on the measurement structure, and   identifying a single indicia of a set of indicia on the scale portion of the reference structure aligned with the single indicium of the measurement structure, the identified single indicia identifying the indicated size of the femoral component.   
     
     
         3 . The method of  claim 2 , wherein noting the indicated size of the bearing component using the second scale of the measurement structure and the reference structure includes identifying a single indicia of a set of indicia on the measurement structure aligned with the identified single indicia of the reference structure. 
     
     
         4 . The method of  claim 1 , wherein locating the measurement structure on the intramedullary rod by positioning the end of the rod includes positioning the end of the rod through a plurality of slots in the wall of a housing of the measurement structure and through a hole in a connector block of the measurement structure. 
     
     
         5 . The method of  claim 1 , wherein drawing the plate member of the measurement structure upwardly to engage the upper face of the plate member with the at least one posterior condyle includes turning a knob on the measurement structure. 
     
     
         6 . The method of  claim 1 , wherein moving the plate member of the measurement structure downwardly includes sliding the measurement structure relative to the reference structure.