title: Analysis of the Flexion Gap on In Vivo Knee Kinematics Using Fluoroscopy.
abstract: There is a paucity of information on the relationships between postoperative knee laxity and in vivo knee kinematics. The correlations were analyzed in 22 knees with axial radiographs and fluoroscopy based 3D model fitting approach after a tri-condylar total knee arthroplasty. During deep knee bend activities, the medial flexion gap had significant correlations with the medial contact point (r=0.529, P=0.011) and axial rotation at full extension. During kneeling activities, a greater medial flexion gap caused larger anterior translation at complete contact (r=0.568, P=0.011). Meanwhile, the lateral flexion gap had less effect. In conclusion, laxity of the medial collateral ligament should be avoided because the magnitude of medial flexion stability was crucial for postoperative knee kinematics.
authors: Department of Orthopedic Surgery, Kyoto University, Graduate School of Medicine, Kyoto, Japan; Center for Musculoskeletal Research, University of Tennessee, Knoxville, TN.
authors: Shinichiro
authors: S
authors: Nakamura
authors: Department of Orthopedic Surgery, Kyoto University, Graduate School of Medicine, Kyoto, Japan.
authors: Hiromu
authors: H
authors: Ito
authors: Department of Orthopedic Surgery, Kyoto University, Graduate School of Medicine, Kyoto, Japan.
authors: Hiroyuki
authors: H
authors: Yoshitomi
authors: Department of Orthopedic Surgery, Kyoto University, Graduate School of Medicine, Kyoto, Japan.
authors: Shinichi
authors: S
authors: Kuriyama
authors: Center for Musculoskeletal Research, University of Tennessee, Knoxville, TN.
authors: Richard D
authors: RD
authors: Komistek
authors: Department of Orthopedic Surgery, Kyoto University, Graduate School of Medicine, Kyoto, Japan.
authors: Shuichi
authors: S
authors: Matsuda
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D001696:Biomechanical Phenomena; D017885:Collateral Ligaments / Q000601:surgery*; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007717:Knee / Q000502:physiology / Q000601:surgery*; D007719:Knee Joint / Q000502:physiology / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery; D011184:Postoperative Period; D011187:Posture; D016059:Range of Motion, Articular; D012399:Rotation
keywords: Flexion gap; Fluoroscopy; Kinematics; Ligament balance; Medial collateral ligament; Total knee arthroplasty