The kinematics and strategies of recovery steps during lateral losses of balance in standing at different perturbation magnitudes in older adults with varying history of falls.

BACKGROUND: Step-recovery responses are critical in preventing falls when balance is lost unexpectedly. We investigated the kinematics and strategies of balance recovery in older adults with a varying history of falls. METHODS: In a laboratory study, 51 non-fallers (NFs), 20 one-time fallers (OFs), and 12 recurrent-fallers (RFs) were exposed to random right/left unannounced underfoot perturbations in standing of increasing magnitude. The stepping strategies and kinematics across an increasing magnitude of perturbations and the single- and multiple-step threshold trials, i.e., the lowest perturbation magnitude to evoke single step and multiple steps, respectively, were analyzed. Fall efficacy (FES) and self-reported lower-extremity function were also assessed. RESULTS: OFs had significantly lower single- and multiple-step threshold levels than NFs; the recovery-step kinematics were similar. Surprisingly, RFs did not differ from NFs in either threshold. The kinematics in the single-step threshold trial in RFs, however, showed a significant delay in step initiation duration, longer step duration, and larger center of mass (CoM) displacement compared with NFs and OFs. In the multiple-step threshold trial, the RFs exhibited larger CoM displacements and longer time to fully recover from balance loss. Interestingly, in the single-stepping trials, 45% of the step-recovery strategies used by RFs were the loaded-leg strategy, about two times more than OFs and NFs (22.5 and 24.2%, respectively). During the multiple-stepping trials, 27.3% of the first-step recovery strategies used by RFs were the loaded-leg strategy about two times more than OFs and NFs (11.9 and 16.4%, respectively), the crossover stepping strategy was the dominated response in all 3 groups (about 50%). In addition, RFs reported a lower low-extremity function compared with NFs, and higher FES in the OFs. CONCLUSIONS: RFs had impaired kinematics during both single-step and multiple-step recovery responses which was associated with greater leg dysfunction. OFs and NFs had similar recovery-step kinematics, but OFs were more likely to step at lower perturbation magnitudes suggesting a more "responsive" over-reactive step response related from their higher fear of falling and not due to impaired balance abilities. These data provide insight into how a varying history of falls might affect balance recovery to a lateral postural perturbation. TRIAL REGISTRATION: This study was registered prospectively on November 9th, 2011 at clinicaltrials.gov ( NCT01439451 ).

Fear of Falls, Physical Performance and Physical Activity Levels among Older Adults with Falls and Recurrent Falls / Jurnal Sains Kesihatan Malaysia

@#Older adults who fall recurrently have sub-optimal physical performance especially muscle strength, mobility and balance. Recurrent falls lead to a heightened fear of falls. However, there is limited information regarding other domains of physical performance, namely, flexibility and endurance. In addition there is still limited knowledge pertaining fear of falls and physical activity levels among Malaysian community-dwelling older adults who are recurrent fallers. The aim of our study was to compare fear of falls, physical performance and physical activity levels among older adults with falls and recurrent falls. This cross- sectional study was carried out in two Malaysian urban districts. Physical performance was examined using Functional Fitness MOT (FFMOT). Modified Baecke Questionnaire and Activities-Specific Balance Confidence (ABC-6) Scale were administered to evaluate the level of daily physical activity and fear of falls respectively. A total 35 older adults participated in this study, 20 fallers (mean age :71.95±8.22) and 15 recurrent fallers (mean age: 76.73±8.82) respectively. Our study results showed that older adults with recurrent fallers had significantly reduced lower extremity strength, dynamic balance, endurance, balance confidence in ADL and physical activity levels compared to faller group (p<0.05). Although flexibility and upper limb strength were not significantly different among fallers and recurrent fallers, overall improvement in physical performance should be targetted in falls prevention and management. This is vital to prevent further deterioration in physical performance among older adults with recurrent falls.