Article

The step-up activity (stair-ascending) is an important daily function of the
knee. This study aimed to investigate the articular cartilage contact kinematics
on both tibial and femoral cartilage surfaces and describe the femoral condylar
motion using the transepicondylar axis (TEA) and the geometric center axis (GCA)
during a step-up activity. Twenty-one healthy subjects were included and their
knee joint models were reconstructed using MR images. A single-stair step-up
activity was imaged using a dual-fluoroscopic imaging system. Three-dimensional
knee joint contact points were determined and projected onto the tibial plateau
and femoral condylar surfaces. The contact points on the medial and lateral
tibial plateau moved anteriorly (by 13.5+/-3.2 and 10.7+/-5.0 mm, respectively,
p>0.05) with knee extension. The contact points on the medial and lateral femoral
condyle moved from the posterior to the anterior portion (by 32.2+/-4.9 mm and
25.5+/-4.2 mm, respectively, p<0.05) and were located on the inner half of the
femoral cartilage throughout the activity. The data on articular contact
kinematics and the femoral condylar motion described using the TEA and GCA
indicated that the medial and lateral compartments had similar motion patterns
during the step-up activity. The knee does not demonstrate a medial-pivoting
motion character during the step-up activity. The data may provide insight to
contemporary TKA development.
CI - Copyright (c) 2013 Elsevier B.V. All rights reserved.

Langue : ANGLAIS