Role of computer-assisted surgery in osteotomies around the knee

The goal of this article is to present our experience on navigation for osteotomies around the knee and especially osteotomies for coronal deformities. The first computer-assisted osteotomy was performed in March 2001 and since that time more than 1000 osteotomies have been performed in our department.

All the osteotomies were performed with the Orthopilot^® device (B-Braun-Aesculap, Tuttlingen, Germany). The main indication was for genu varum deformities but several cases were operated for genu valgum. The surgical procedure as well as the indications and the rationale for each osteotomy (high tibial osteotomy-HTO, double-level osteotomy-DLO, femoral osteotomy-FO) are addressed in the article.

The results are focused on several papers published by the authors since more than 10 years. Regarding HTO for genu varum, the preoperative goal (HKA angle: 184° ± 2°) was reached in 96 % of cases and the difference was statistically significant compared to the non-navigated series (71 %: p < 0.05). Regarding DLO for genu varum, the preoperative goal was reached in 92.7 % for the HKA angle and in 88.1 % for the medial proximal tibial mechanical angle (MPTMA). Regarding genu valgum deformity, the preoperative goal was achieved in 86.2 % of cases for the HKA angle and 100 % of cases for the MPTMA.

According to these results, one can say that, regardless the type of osteotomy, the procedure is reliable, reproducible and accurate. Since 15 years, all the osteotomies around the knee are navigated in our department. Provided that one uses a reproducible radiograph protocol, navigation allows to perform double-level osteotomies, both for genu varum and genu valgum, with optimal accuracy in order to avoid oblique joint line, which will be difficult to revise to TKA.

IV.