Extramedullary Guides Versus Portable, Accelerometer-Based Navigation for Tibial Alignment in Total Knee Arthroplasty: A Randomized, Controlled Trial: Winner of the 2013 HAP PAUL Award

Extramedullary (EM) tibial alignment guides have demonstrated a limited degree of accuracy in total knee arthroplasty (TKA). The purpose of this study was to compare the tibial component alignment obtained using a portable, accelerometer-based navigation device versus EM alignment guides. One hundred patients were enrolled in this prospective, randomized controlled study to receive a TKA using either the navigation device, or an EM guide. Standing AP hip-to-ankle and lateral knee-to-ankle radiographs were obtained at the first, postoperative visit. 95.7% of tibial components in the navigation cohort were within 2° of perpendicular to the tibial mechanical axis, versus 68.1% in the EM cohort (P < 0.001). 95.0% of tibial components in the navigation cohort were within 2° of a 3° posterior slope, versus 72.1% in the EM cohort (P = 0.007). A portable, accelerometer-based navigation device decreases outliers in tibial component alignment compared to conventional, EM alignment guides in TKA.