Related Experiment Video
Updated: May 18, 2026
Three-Dimensional Preoperative Virtual Planning in Derotational Proximal Femoral Osteotomy
Published on: February 17, 2023
Deviation between navigated and final 3-dimensional implant position in mini-invasive unicompartmental knee
Nicolas Martinez-Carranza1, Lars Weidenhielm, Joakim Crafoord
1Department of Orthopaedics, Karolinska University Hospital, Stockholm, Sweden. nicolas.martinez-carranza@karolinska.se
Background And Purpose:
Unicompartmental knee arthroplasty (UKA) is an established method of treating isolated gonartrosis. Modern techniques such as computer-assisted surgery (CAS) and minimally invasive surgery (MIS) are attractive complementary methods to UKA. However, the positioning of the components remains a concern. Thus, we performed a prospective study to assess whether there was deviation between the navigated implant position and the final implant position.
Patients And Methods:
We performed UKA with MIS and CAS in 13 patients. By comparing intraoperative navigation data with postoperative computed tomography (CT) measurements, we calculated the deviation between the computer-assisted implant position and the final 3-D implant position of the femoral and tibial components.
Results:
The computer-assisted placement of the femoral and tibial component showed adequate position and consistent results regarding flexion-extension and varus-valgus. However, regarding rotation there was a large variation and 6 of 10 patients were outside the target range for both the femoral component and the tibial component.
Interpretation:
Difficulties in assessing anatomical landmarks with the CAS in combination with MIS might be a reason for the poor rotational alignment of the components.
