Investigation of fall prediction factors in elderly population using isokinetic assessment of the lower extremities

The purpose of the present study was to investigate for predictive factors for falls in the elderly population after lower extremity strength assessment in an isokinetic dynamometer and to construct a discrimination model for the classification of the elderly in a fallers and non-fallers group. 59 community dwelling elderly men and women aged60 years and older with or without a history of falls all in good health were selected to participate in the study. For the assessment, we used six concentric and two eccentric speeds isokinetically (60°, 90°, 120°, 180°, 240°, 300°/secand 60°, 120°/sec respectively) and four different angular positions isometrically (75°, 60°, 45°, 30° of knee flexion,0°=anatomical zero). All measures were conducted with a Cybex Norm Isokinetic Dynamometer in the knee joint for both legs in flexion and extension. T-test was used in order to identify differences between fallers and non-fallers. Step-wise discriminant analysis performed in order to reveal the factors for classification of the elderly in fallers/non-fallers group. Statistical significant differences (p<0.05) were ob-served for strength and power measures in 42 of the 60variables, between the two groups (fallers/non-fallers), with non-fallers performing better in all examined variables. Three variables out of the initially 42 that included in the discriminant analysis were present in the discriminant model: Mean peak torque in 120°/sec in Extension, mean total work in 60°/secin flexion and mean total work ratio (Flexors/Extensors) in 60°/sec. These three variables classified correctly the 91.4% of the cases in the fallers/non-fallers groups. The conclusion of the researchers was that isokinetic and isometric assessment of the lower extremities strength in the elderly population can discriminate fallers and non fallers. As a result we can therefore classify older people in prevention programs according to their probability for falls.