Kinematic magnetic resonance imaging of the effect of bracing on patellar position: qualitative assessment using an extremity magnetic resonance system

J Athl Train. 2000 Jan;35(1):44-9.

Abstract

Objective: To use an extremity magnetic resonance system to perform kinematic magnetic resonance imaging (MRI) of the patellofemoral joint to qualitatively assess the effect of bracing on patellar position.

Design and setting: Subjects underwent kinematic MRI of the symptomatic extremity with a 0.2-Tesla extremity magnetic resonance system. Images were obtained using a knee coil and a T1-weighted, spin echo pulse sequence.

Subjects: Seven female patients with patellofemoral joint symptoms.

Measurements: FOUR DIFFERENT AXIAL SECTIONS WERE OBTAINED FOR EACH POSITION: extension and 3 positions of flexion up to 36 degrees . An appropriate-sized patellofemoral brace was applied, and the kinematic MRI procedure was repeated.

Results: Six patients had lateral displacement of the patella, and 1 patient had medial displacement of the patella. After application of the brace, 6 patients (5 with lateral displacement and 1 with medial displacement, 86%) exhibited correction (5) or improvement (1 with lateral displacement) in the abnormal patellar positions, and 1 patient had worsening of the abnormal position of the patella.

Conclusions: We used kinematic MRI to determine the presence of abnormal patellar positioning. Application of the brace counteracted the abnormal patellar positions in most of the patients studied.