Characterization of patellar maltracking using dynamic kinematic CT imaging in patients with patellar instability

Abstract

IV.

Dynamic Evaluation of Patellofemoral Instability: A Clinical Reality or Just a Research Field? A Literature review

“…The study was performed under no‐WB and described statistically significant differences in most parameters. The same group also demonstrated how DKCT can differentiate specific patterns of patellar maltracking, establishing a grading system of 10 categories with high correlation with the severity of symptoms; only one of them was labelled as normal tracking . This variability was also highlighted in a specific review on patellar tracking, concluding that “ there may be no normal pattern ”.…”

Patellar instability can be classified into four types based on patellar movement with knee flexion: a three-dimensional computer model analysis

“…From the 3D point of view, the reference lines on the images created at the mid-patellar level at a certain knee flexion angle do not match the ones at other knee flexion angles in the 3D space. While superimposition of the cross-sectional images at different knee flexion angles seems to be a good solution,5 even this would not accurately interpret the changes of patellar alignment in the 3D space. Thus, in this study, superimposition was performed on the 3D computer models of the femur instead of the contour on cross-sectional axial images, and the references were established in 3D space in place of two-dimensional (2D) images 17 19.…”

“…However, it was difficult to compare their results with ours because their subjects were not limited to the knees of patients with PI and because their analysis was a qualitative study using axial images of clinically used MRI. Recently, Tanaka et al 5 have classified patellar tracking into four categories—normal tracking, lateral tracking, J-sign pattern and reverse J-sign pattern—using dynamic kinematic CT by bisect offset as the parameter. Their method was a conventional 2D analysis, but dynamic kinematic CT during active knee flexion could obtain more physiological tracking of the patella of patients with PI.…”

“…Tanaka et al 5 have recently classified patellar tracking into four categories using dynamic kinematic CT by bisect offset as the parameter. However, accurate evaluation of patellar tracking can be difficult, as the patella moves by three-dimensionally gliding on the femoral trochlea 6–10.…”

Klinische Basisuntersuchung des Kniegelenkes

“…Beim sog. Patellatracking, also dem Gleitvorgang im Femoropatellargelenk, können bewegungsabhängige Luxationstendenzen oder Instabilitäten schließlich auch dynamisch erkannt werden [6]. [8].…”