Biomechanical model analysis of older females' reduced ability to regain balance after a forward fall

摘要

Falls among members of the elderly population are associated with high rates of serious injury. Previous experimental studies have shown that older adults are less successful than young adults when attempting to regain balance with a single stepafter an induced forward fall (Thelen et al, 1997). Older females exhibited particularly poor balance recovery capabilities, with an average maximum lean angle that was seven degrees less than that for older males and fifteen degrees less than that foryoung females (Wojcik et al, 1997).A previous direct dynamics model study (Chen, 1993) suggests that rates of torque development in swing leg hip flexion and stance leg plantarfiexion are significant factors in recovering balance after tripping. In an effort to gain insight into thefactors causing older females' reduced ability to regain balance after a forward fall, a similar two-dimensional, sagittal-plane model was developed to examine the effects of age-related and gender-related changes in muscle strengths, muscle activationtimes, anthropometry, and rates of torque development on single-step recovery.