Location and number of cortical fixation points and the effect on reference base stability during computer-navigated...

This study investigated 2 methods of reference base fixation for computer navigation markers for computer-navigated total knee arthroplasty. Five cadaveric specimens were used to test a 1-pin and 3-pin base system. A navigation system (Stryker Navigation, Kalamazoo, Mich) was used for testing with applied loads and torques to the reference base. Changes in distance from a verification point as well change in alignment were recorded. The change in distance to a reference point as well as the change in alignment data was significantly different at 65 N of applied load with the 3-pin construct being more stable (P = .02). The results suggest that 3-pin fixation in the metaphyseal portion of the distal femur is more stable than a single-pin bicortical construct.