Background

The aim of the present study was to compare the accuracy of prosthetic alignment with three-dimensional computed tomography (3DCT) measurement following total knee Nephew. Inc. Memphis, TN, USA). The operation time between the both groups were investigated. 3DCT scans of the entire lower extremities were taken before and after the surgery. Femoral and tibial alignments in the coronal, sagittal, and axial planes were measured using computer software. The differences of prosthetic alignment and translation between arthroplasty (TKA) performed using a handheld robot-assisted surgical technique (Blue Belt Technologies’ Navio system) versus Manual surgical procedure.

Methods

41 TKAs were performed with the Navio surgical procedure (Navio group) between 2019 and 2020. Another 41 patients underwent TKA with the conventional manual surgical procedure (Manual group) using the same prosthesis (Journey II BCS; Smith& the preoperative 3DCT plan and postoperative 3DCT image were also measured.

Results

There were not statistically significant difference (p= 0.785) about the outlier of post- operative femorotibial angle between the groups. In the tibial axial plane, the mean of prosthetic alignment in anteroposterior (AP) plane was 4.0° in the Navio group and 6.7° in the Manual group (p= 0.006). The rate of outliers for tibial axial alignment in Navio group were significantly less than Manual group (p= 0.009). There were no statistically significant differences between prosthetic translation in the proximal- distal, anterior- posterior and medial- lateral between the groups.

Conclusions

Navio handheld robot-assisted TKA reduced the outliers for rotational alignment of tibial prosthesis as compared to the conventional TKA.