Relationships between alignment, kinematic and kinetic measures of the knee of normal elderly subjects in level walking

Abstract

Twelve normal elderly subjects were tested to analyse the relationships between static radiographic alignment and dynamic kinematic and kinetic measures at the knee in gait. A standard precision radiograph was used to measure the static lower limb alignment and a 3D optoelectric system was used to measure the biomechanical performance of the knee in level walking. Relationships were calculated between static radiographic angular measures and dynamic knee angular measures, dynamic knee joint forces, and dynamic knee joint moments during gait in corresponding motion planes; and between dynamic knee angular measures and dynamic knee joint forces and dynamic knee moments during gait and in corresponding motion planes. The results showed that the static lower-limb alignment measures did not closely correlate with the kinetic measures of the knee in gait although about half of the static angular alignment measures were significantly related to some of the dynamic knee angular measures. Instead, six of nine dynamic angular measures of the knee were significantly related to the dynamic forces and moments of force in the corresponding motion planes. These results suggest that static alignment measures alone at the present time are not sufficient to predict the dynamic knee joint forces in intact knees.