Abstract
The primary objective was to compare the intraoperative data assessed by OrthoPilot
(Aesculap AG, Tuttlingen, Germany) with postoperative coronal and sagittal long-leg
standing radiographs. The secondary objective was to evaluate the influence of sex
and body mass index (BMI) on the accuracy and effectiveness of the implantation of
the knee prosthesis by OrthoPilot. We included 75 patients in our investigation. Participants
received an e.motion (Aesculap AG) knee prosthesis using the OrthoPilot navigation
system. Postoperative long-leg standing anteroposterior and lateral radiographs were
performed. We compared the intraoperative navigational data with postoperative determined
angles of knee geometry. We also compared the sex and BMI of participants to their
difference between intraoperative and postoperative measurements to test for an association.
We found a difference between intraoperative data and radiographs of 1.8 degrees for
the hip-knee-ankle angle. The intraoperative lateral distal femoral angle and medial
proximal tibial angle differed from the radiological analysis by 1.2 degrees, respectively.
The lateral views revealed a difference of 1.6 degrees for femur lateral and 1.4 degrees
for the tibia lateral. There was no significant (p > 0.05) influence of the parameters BMI and sex of the patients on these values.
Our results showed that the implemented intraoperative navigation system is reliable.
It does not differ on average from postoperative radiographs by more than 1.8 degrees.
The findings of our study suggest that a correct postoperative alignment can be achieved
in both high and low BMI participants if a precise range is maintained during the
surgery.
Keywords
total knee arthroplasty - navigation - long-leg standing radiographs - alignment -
BMI
