Description
Objective.
The purpose of this study was to evaluate the dynamics of medial meniscus during knee flexion-extension using ultrasonography in medial meniscus posterior root tear (MMPRT).
Method.
30 patients with MMPRT (MMPRT group), 33 patients with early knee osteoarthritis (EKOA group), and 29 healthy controls (C group) were enrolled in this study. Dynamic ultrasonographic evaluations were performed in all patients. Medial meniscus extrusion (MME) from 0°to 90°of flexion on ultrasonography were compared among three groups.
Result.
The mean MME was 3.3 mm in knee extension and 4.4 mm in 90°flexion in the MMPRT group, 3.6 mm in extension and 2.5 mm in flexion in the EKOA group, and 1.9 mm in extension and 0.5 mm in flexion in the C group. MME significantly increased from 0°to 90°of flexion on ultrasonography in the MMPRT group, while MME significantly decreased in the EKOA group and C group.
Conclusions.
MME decreases from 0°to 90° of flexion on ultrasonography with medial meniscus hoop function maintained, while MMPRT has a lack of decrease in MME from 0°to 90°of flexion. Dynamic evaluation of MME using ultrasonography is useful for the diagnosis of MMPRT.