title: Effects of kneeling on tibiofemoral contact pressure and area in posterior cruciate-retaining and posterior cruciate-sacrificing total knee arthroplasty.
abstract: The objective of this study was to measure the effect of kneeling on tibiofemoral contact following cruciate-retaining and posterior-stabilized total knee arthroplasty. Five cadaveric knees were tested on a custom testing system that allowed physiologic muscle loading. Three forces were used to simulate nonkneeling, double-stance kneeling, and single-stance kneeling at flexion angles of 90°, 105°, 120°, and 135°. Tibiofemoral contact areas and pressures were measured using the Tekscan (South Boston, MA) system. Kneeling increased contact areas and pressures in both designs with variable significance (P < .05). Moving from double- to single-stance kneeling increased pressures in the cruciate-retaining group but decreased pressures in the posterior-stabilized group (P < .05). Chronic, repetitive kneeling after total knee arthroplasty may increase polyethylene wear due to increased contact areas and pressures.
authors.affiliation: Orthopaedic Biomechanics Laboratory, Long Beach VA Healthcare System and University of California, Irvine, CA, USA.
authors.forename: Jason K
authors.initials: JK
authors.lastname: Hofer
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Gejo
authors.forename: Michelle H
authors.initials: MH
authors.lastname: McGarry
authors.forename: Thay Q
authors.initials: TQ
authors.lastname: Lee
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D005269:Femur; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D020959:Polyethylene; D016119:Posterior Cruciate Ligament / Q000601:surgery*; D011187:Posture; D011312:Pressure; D016059:Range of Motion, Articular; D013977:Tibia; D016474:Weight-Bearing
chemical_list: D020959:Polyethylene