The Advantages of Navigation for a Novice Surgeon in Performing Total Knee Replacement Surgery / 대한정형외과학회잡지

ABSTRACT

PURPOSE: To compare the outcomes of navigation-assisted total knee replacement conducted by a skilled surgeon and novice surgeon, as well as to evaluate the usefulness of the navigation assistance to a novice surgeon. MATERIALS AND METHODS: We retrospectively made a comparison between 60 total knee replacement surgeries conducted by skilled surgeon and 60 total knee replacement surgeries by a novice surgeon during the 2015. Scanograms were taken both preoperatively and at 3-month postoperatively to measure the accuracy of bone cutting and alignment. As for external rotation of the femur, we checked the values of the distal femur surgical epicondyle axis, and the posterior condyle axis displaced by the navigator after bone registration for both novice and skilled groups. For postoperative functional examination, Knee Society Score (KSS) were evaluated at 1-year follow-up. RESULTS: Forty-nine knees in the skilled group, and 51 knees in the novice group achieved coronal axis alignment of hip knee ankle values of 0°±3°. The mean external rotation degree of the femoral epicondyle axis against the posterior condyle axis, measured by the navigator, was 3.8°±2.9° in skilled group, and 1.2°±3.0° in novice group. When regarding femoral epicondyle axis, which showed a more internal rotation than the posterior condylar axis as an outlier, six cases were outlier in skilled group, while, 18 cases were outlier in novice group. After revising external rotation value of femoral implants comparing values navigation displaced and values using 3° external rotation manual jig against femoral posterior condylar axis, the skilled group showed 0 case of outlier and the novice group showed 10 cases of outlier. The mean KSS knee assessed at 1 year postoperatively was 83.2±6.8 in skilled group, and 83.1±7.0 in novice group, with no statistically significant difference. CONCLUSION: Navigation provides advantages to novice surgeon to achieve stabilized coronal plane axis, as well as accurate resection of the femur and tibia. However, the navigation does not provide any advantages in achieving the aimed amount of femoral external rotation to novice surgeons.