Control of knee coronal plane moment via modulation of center of pressure: a prospective gait analysis study.
OBJECTIVE
Footwear-generated biomechanical manipulations (e.g., wedge insoles) have been shown to reduce the magnitude of adduction moment about the knee. The theory behind wedged insoles is that a more laterally shifted location of the center of pressure reduces the distance between the ground reaction force and the center of the knee joint, thereby reducing adduction moment during gait. However, the relationship between the center of pressure and the knee adduction moment has not been studied previously. The aim of this study was to examine the association between the location of the center of pressure and the relative magnitude of the knee adduction moment during gait in healthy men.


METHODS
A novel foot-worn biomechanical device which allows controlled manipulation of the center of pressure location was utilized. Twelve healthy men underwent successive gait analysis testing in a controlled setting and with the device set to convey three different para-sagittal locations of the center of pressure: neutral, medial offset and lateral offset.


RESULTS
The knee adduction moment during the stance phase significantly correlated with the shift of the center of pressure from the functional neutral sagittal axis in the coronal plane (i.e., from medial to lateral). The moment was reduced with the lateral sagittal axis configuration and augmented with the medial sagittal axis configuration.


CONCLUSIONS
The study results confirm the hypothesis of a direct correlation between the coronal location of the center of pressure and the magnitude of the knee adduction moment.
Haim
Amir
A
Biorobotics and Biomechanics Lab (BRML), Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, 32000 Haifa, Israel. myrnaperlmutter@gmail.com
Rozen
Nimrod
N
Dekel
Samuel
S
Halperin
Nachum
N
Wolf
Alon
A
D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D003198:Computer Simulation; D005528:Foot / Q000502:physiology*; D005684:Gait / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D011312:Pressure; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology*; D019415:Torque; D016138:Walking / Q000502:physiology*