title: 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.
abstract: 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.
authors.affiliation: Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, Missouri.
authors.forename: Denis
authors.initials: D
authors.lastname: Nam
authors.affiliation: Adult Reconstruction and Joint Replacement Service, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, New York.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Cody
authors.affiliation: Adult Reconstruction and Joint Replacement Service, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, New York.
authors.forename: Joseph T
authors.initials: JT
authors.lastname: Nguyen
authors.affiliation: Adult Reconstruction and Joint Replacement Service, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, New York.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Figgie
authors.affiliation: Adult Reconstruction and Joint Replacement Service, Department of Orthopaedic Surgery, Hospital for Special Surgery, Weill Medical College of Cornell University, New York, New York.
authors.forename: David J
authors.initials: DJ
authors.lastname: Mayman
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D001363:Awards and Prizes; D017760:Bone Malalignment / Q000517:prevention & control*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009985:Orthopedics; D012955:Societies, Medical; D025321:Surgery, Computer-Assisted; D013977:Tibia / Q000601:surgery*; D014481:United States
keywords: component alignment; computer navigation; posterior slope; tibial alignment; total knee arthroplasty