This Phase II STTR project involves the continued development of a safe, low-cost, portable device to measure maximum voluntary muscle power generated during fundamental movements of the hip and knee. The goal is to provide an objective and sensitive geriatric tool for easily assessing the physical domain that best predicts the ability to successfully arrest an on-going fall. The execution of rapid steps needed to regain balance requires high levels of hip and knee power that may exceed the capacity of an elderly individual. Nevertheless, leg power is rarely measured during geriatric assessments because accurate, portable, cost effective devices for the measurement are not commercially available. Consequently, Bio Logic Engineering will enhance and commercialize the Phase I prototype to provide measures of power generation during isolated hip and knee movements performed in the gravity free plane. Power and strength measures from 40 healthy younger, 40 healthy older subjects, and from 20 slower older female walkers will be compared with results obtained on a standard isokinetic system. Because higher speed movements appear more relevant, the hypothesis will be tested that 240 deg/sec power data will explain more of the variability on a forward fall recovery test than do 120 deg/sec data. PROPOSED COMMERCIAL APPLICATION: Our primary goals are to provide a tool to improve geriatric assessment and rehabilitation, and in the long-term possibly aid in the reduction of falls suffered by the elderly. The market for the device is widespread considering its use in geriatric research, orthopedic rehab, sports medicine, group practices, medical centers, hospitals, assisted living centers, athletic training, etc. We anticipate sales volume to be in the thousands to many tens of thousands of units at an estimated retail cost of $5,000 each. A considerable increase in commercial potential may be realized if future research validates its clinical utility in aiding in the assessment of the physical capacity of an elderly individual to recover from a loss of balance.