Computer Assisted Knee Arthroplasty Instrumentation, Systems, and Processes

Abstract

Instrumentation, systems, and processes for tracking anatomy, instrumentation, trial implants, implants, and references, and rendering images and data related to them in connection with surgical operations, for example total knee arthroplasties (“TKA”). These instrumentation, systems, and processes are accomplished by using a computer to intraoperatively obtain images of body parts and to register, navigate, and track surgical instruments. Disclosed in this document are also alignment modules and other structures and processes which allow for coarse and fine alignment of instrumentation and other devices relative to bone for use in connection with the tracking systems of the present invention.

1 . A process for conducting knee surgery, comprising: 
 a. exposing bones in the vicinity of knee joint;    b. fastening a rod to bone in the vicinity of the knee joint in a manner intended at least coarsely to align the rod to a desired axis relative to the bone;    c. attaching a rod retention component of an alignment module to the rod, the alignment module comprising: 
 i. a rod retention component adapted to connect to the rod;  
 ii. a surgical instrumentation retention component adapted to connect to surgical instrumentation;  
 iii. an intermediate component adapted to connect to the rod retention component in a fashion that allows the rod retention component and intermediate component to rotate relative to each other about at least one axis, and adapted to connect to the surgical instrumentation retention component in a fashion that allows the surgical instrumentation retention component and the intermediate component to rotate relative to each other about at least one axis;  
 iv. an adjustment mechanism connecting the intermediate component and the rod retention component, the adjustment mechanism adapted to control and fix orientation of the intermediate component relative to the rod retention component; and  
 v. an adjustment mechanism connecting the intermediate component and the surgical instrumentation retention component, the adjustment mechanism adapted to control and fix orientation of the intermediate component and the surgical instrumentation retention component;  
   d. attaching instrumentation to the alignment module;    e. adjusting at least one of the adjustment mechanisms in order to finely align the instrumentation relative to the bone;    f. resecting bone using the instrumentation;    g. attaching a surgical implant to the resected bone;    h. reassembling the knee; and    i. closing the exposed knee.    
     
     
         2 . The process according to  claim 1 , further comprising attaching a fiducial at least indirectly to the instrumentation and tracking the instrumentation position using the fiducial and a surgical navigation system.  
     
     
         3 . The process according to  claim 1 , in which fastening the rod to the bone does not include penetrating the medullary canal with the rod.  
     
     
         4 . The process according to  claim 1 , in which the instrumentation is adjusted by adjusting both adjustment mechanisms.  
     
     
         5 . A process for conducting knee surgery, comprising: 
 a. exposing bones in the vicinity of knee joint;    b. fastening a structural member to bone in the vicinity of the knee joint in a manner intended at least coarsely to align the structural member to a desired axis relative to the bone;    c. attaching a second member of an alignment module to the structural member, the alignment module comprising: 
 i. a first member adapted to be connected to instrumentation;  
 ii. a second member connected to the first member in a fashion that allows the second member and the first member to be varied in orientation relative to each other about at least two substantially orthogonal axes;  
 iii. adjustment structure for controlling motion of the second member relative to the first member and for fixing the position of the second member relative to the first member;  
 iv. attaching instrumentation to the first member; and  
 v. attaching at least one fiducial to the instrumentation, at least indirectly;  
   d. tracking orientation of the instrumentation relative to bone using the fiducial and a surgical navigation system;    e. adjusting the adjustment structure in order to finely align the instrumentation relative to the bone;    f. resecting bone using the instrumentation;    g. attaching a surgical implant to the resected bone;    h. reassembling the knee; and    i. closing the exposed knee.    
     
     
         6 . A process according to  claim 5 , in which tracking orientation of the instrumentation relative to the bone involves storing, processing and displaying radiograms of the bone taken before the process begins.