Effects of musculoskeletal and sensory degradation due to aging on the biomechanics of slips and falls.
Woldstad-JC; Lockhardt-TE; Hsiang-S
NIOSH 2000 Dec; :1-6
The proposal called for a one-year study to investigate the process of initiation and recovery of inadvertent slips and falls. The specific aim of the proposed research was to investigate the changes in the biomechanical parameters of walking and ground reaction forces due to intrinsic deficits associated with increase in age. More specifically, how deterioration of muscular strength and sensory degradation among older individuals affect biomechanical parameters of slip and fall accidents under normal and abnormal conditions. The investigation compared biomechanical parameters of walking in three age groups; (18-30 years), (35-59 years), and 65 years or over). Biomechanical parameters included; stride length, heel velocity, required coefficient of friction, slip distance, and position and velocity of center of gravity of the whole body during heel contact phase of the gait. These parameters were measured utilizing force platforms, a 3-D motion analysis system, and a fall arresting rig. To determine the position and velocity of center of gravity during heel contact phase of the gait, a 3-D link segment model was utilized. Walking surfaces included oily vinyl tiles (dynamic coefficient of friction (DCOF) = 0.08) and outdoor carpet (DCOF = 1.80). Subjects walked according to their natural cadences. A sensory organization test was also performed to obtain information concerning the subject's proprioceptive, visual and vestibular systems. These sensory components were measured using an Equitest Posturography Platform. In addition, isometric strength test was preformed (using a force transducer) to obtain information concerning the subject's over all strength. The results indicated that younger subjects slipped as often as the elderly subject; however, the recovery process of older individuals was much slower and less effective. The ability to successfully recover from a slip (thus preventing a fall) is believed to be affected by lower extremity muscle strength and sensory degradation in elderly individuals.
Walking-surfaces; Environmental-hazards; Muscle-stress; Muscle-tissue; Age-factors; Age-groups; Surface-properties; Accident-prevention; Injury-prevention; Biomechanics; Ergonomics; Control-technology; Engineering-controls; Analytical-models; Analytical-processes
Institute for Ergonomics Research, Texas Tech University, Lubbock, Texas 79409-3061
Final Grant Report
National Institute for Occupational Safety and Health
Texas Tech University, Lubbock, TX 79409-3061