Accelerometer-Based Navigation Is as Accurate as Optical Computer Navigation in Restoring the Joint Line and Mechanical Axis After Total Knee Arthroplasty: A Prospective Matched Study.

Abstract The Zimmer iASSIST system is a novel accelerometer-based navigation system for TKA. 76 patients (76 knees) were prospectively matched for age, BMI, gender, diagnosis, and pre-operative scores, and underwent TKA using the iASSIST (n=38) or optical CAS (n=38). There were no significant differences in clinical outcomes or satisfaction rates at six months post-operatively ( P >0.05). Mechanical axis was 1.8±1.3° in the iASSIST cohort versus 2.1±1.6° in the CAS cohort ( P =0.543). There were no significant differences in number of outliers for mechanical axis ( P =1.000), coronal femoral-component angle ( P =0.693), coronal tibial-component angle ( P =0.204) or joint line deviation ( P =1.000). The duration of surgery was significantly longer in the CAS group ( P