title: In Vivo Kinematics of Healthy and Osteoarthritic Knees During Stepping Using Density-Based Image-Matching Techniques.
abstract: The purpose of this study was to investigate in vivo kinematics in healthy and osteoarthritic (OA) knees during stepping using image-matching techniques. Six healthy volunteers and 14 patients with a medial OA knee before undergoing total knee arthroplasty performed stepping under periodic anteroposterior radiograph images. We analyzed the three-dimensional kinematic parameters of knee joints using radiograph images and CT-derived digitally reconstructed radiographs. The average extension/flexion angle ranged 6°/53° and 16°/44° in healthy and OA knees, with significant difference in extension (P = .02). The average varus angle was -2° and 6° in healthy and OA knees, with a significant difference (P = .03). OA knees showed 1.7° of significantly larger varus thrust (P = .04) and 4.2 mm of significantly smaller posterior femoral rollback (P = .04) compared with healthy knees. Coronal limb alignment in OA knees significantly correlated with varus thrust (R2= .36, P = .02) and medial shift of the femur (R2= .34, P = .03). Both normal and OA knees showed no transverse plane instability, including anteroposterior, mediolateral directions, or axial rotation. In conclusion, OA knees demonstrated different kinematics during stepping from normal knees: less knee extension, larger varus thrust, less posterior translation, and larger medial shift.
authors.affiliation: 1 Kyushu University.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hamai
authors.affiliation: 1 Kyushu University.
authors.forename: Ken
authors.initials: K
authors.lastname: Okazaki
authors.affiliation: 2 Kyushu Sangyo University.
authors.forename: Satoru
authors.initials: S
authors.lastname: Ikebe
authors.affiliation: 1 Kyushu University.
authors.forename: Koji
authors.initials: K
authors.lastname: Murakami
authors.affiliation: 2 Kyushu Sangyo University.
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Higaki
authors.affiliation: 1 Kyushu University.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakahara
authors.affiliation: 3 Fukuoka Institute of Technology.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Shimoto
authors.affiliation: 1 Kyushu University.
authors.forename: Hideki
authors.initials: H
authors.lastname: Mizu-Uchi
authors.affiliation: 1 Kyushu University.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Akasaki
authors.affiliation: 1 Kyushu University.
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Iwamoto
mesh_terms: D000328:Adult; D019645:Arthroplasty, Replacement, Knee; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000502:physiology* / Q000503:physiopathology; D008297:Male; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D014057:Tomography, X-Ray Computed; D016138:Walking / Q000502:physiology*
keywords: kinematics; knee joint; osteoarthritis; stepping; varus thrust