title: Patellar tracking and patellofemoral geometry in deep knee flexion.
abstract: Patellar tracking and femoral condylar geometry in deep knee flexion were evaluated using magnetic resonance imaging. The patellar tilting angle, patellar shift, and patellar anteroposterior translation from 0 degrees to 135 degrees flexion were measured. The depth of the femoral condylar articular surface and the curvature of the femoral condylar articular surface also were measured at 135 degrees flexion. The patella shifted laterally, tilted medially, and sank deeply into the intercondylar notch during deep knee flexion. The articular surface of the lateral condyle, existing deep within the intercondylar notch, began to curve steeply at a point farther from the center of the intercondylar notch than did the medial condyle. The geometry of the femoral condyle is adequate to fit the patellar geometry. Results of the current study suggest that the geometry of the lateral femoral condyle allows the patella to track smoothly with a larger patellofemoral contact area and less patellofemoral pressure during deep flexion.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu Sangyo University, Fukuoka, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Moro-oka
authors.forename: Shuichi
authors.initials: S
authors.lastname: Matsuda
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Miura
authors.forename: Ryuji
authors.initials: R
authors.lastname: Nagamine
authors.forename: Ken
authors.initials: K
authors.lastname: Urabe
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kawano
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Higaki
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Iwamoto
mesh_terms: D000328:Adult; D005269:Femur / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000033:anatomy & histology* / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010329:Patella / Q000033:anatomy & histology* / Q000502:physiology*; D011336:Probability; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology*; D012016:Reference Values; D012680:Sensitivity and Specificity