Effects of anteriorly-loaded treadmill walking on dynamic gait stability in young adults

BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η² = 0.114) and liftoff (p = 0.122, η² = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η² = 0.648) and liftoff (p < 0.001, η² = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η² = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.     

Structural and functional foot and ankle characteristics associated with falls in older people

BackgroundFalls affect approximately one in three older people, and foot problems are amongst the modifiable potential risk factors.Research questionwhat are the associations between foot and ankle functional and structural characteristics with falls in community-dwelling older adults?MethodOne hundred eighty-seven community-dwelling older adults (106 females) aged 62–90 years (mean 70.5 ± 5.2) from Isfahan, Iran were recruited. Foot and ankle structure and function (including foot posture, range of motion, muscle strength, deformity, pain and plantar loading patterns during walking) were measured. Fall history was documented in the preceding year. Univariate analyses compared fallers and non-fallers on all variables to determine significant differences and logistic regression analysis identified variables independently associated with falls.ResultsSeventy-four participants (39.9 %) had experienced a fall in the previous year. Logistic regression analysis revealed that less first metatarsophalangeal joint extension (odds ratio 0.82, 95 % CI 0.73−0.91), less plantarflexor muscle strength (odds ratio 0.29, 95 % CI 0.15−0.55), greater pressure-time integral in the medial forefoot (odds ratio 2.65, 95 %CI 1.10–6.38), greater center of pressure velocity in the forefoot (odds ratio 1.27, 95 % CI 1.07–1.49) and greater foot pain (odds ratio 1.09, 95 % CI 1.02–1.16) were significantly and independently associated with falls after accounting for physiological falls risk factors.SignificanceWe have identified several structural and functional foot and ankle characteristics associated with falling in older people. Future development of interventions to help prevent or treat these potentially modifiable risk factors may help decrease the risk of falling in this population.     

Polio survivors have poorer walking adaptability than healthy individuals

BackgroundFalling is a major health problem in polio survivors, often occurring as a result of tripping, slipping or misplaced steps. Therefore, reduced walking adaptability possibly plays an important role.Research questionDoes walking adaptability, assessed on an interactive treadmill, differ between polio survivors and healthy individuals?MethodsIn this cross-sectional study, 48 polio survivors with at least one reported fall in the past year and/or fear of falling and 25 healthy individuals of similar age walked at self-selected comfortable fixed speed on an instrumented treadmill. Walking adaptability was measured as i) target-stepping accuracy (determined as variable error [VE] in mm independent of speed) in three conditions; 0 %, 20 % and 30 % variation in step length and width, and ii) anticipatory and reactive obstacle avoidance (ObA and ObR, in percentage successfully avoided). All trials were checked for valid step detection.Results46 polio survivors (mean ± SD age: 63.2 ± 8.7 years) and 25 healthy individuals (64.3 ± 6.6 years, p = 0.585) showed valid step detection. Compared to healthy individuals (mean±SE VE: 30.6±1.2 mm), polio survivors stepped less accurately onto targets (36.4±0.9 mm, p = 0.001), especially with their least-affected leg. Polio survivors avoided fewer obstacles successfully (mean±SE ObA: 83±3 %, ObR: 59±4 %) than healthy individuals (100±0.3 %, p < 0.001 and 94±3 %, p < 0.001, respectively), with a stronger decline in success rates from anticipatory to reactive obstacle avoidance for polio survivors (p < 0.001).SignificancePolio survivors reporting falls and/or fear of falling had a demonstrably reduced walking adaptability, especially so for reactive obstacle avoidance, which requires step adjustments under high time-pressure demands. Future research should study the merit of walking-adaptability assessment to currently used clinical methods of fall-risk assessment within this population.     

Individual analysis of dynamic stability for twenty-four Tai Chi forms among persons with knee osteoarthritis: A pilot study

BackgroundTai Chi (TC) training has been increasingly used to prevent falls. However, the underlying biomechanical mechanisms of TC training which influence fall risk remain unknown. As a result, the selection of TC forms differs among studies, leading to inconsistent results.Research questionIs dynamic stability different between the simplified 24 Yang-style TC forms among adults with knee osteoarthritis?MethodsTen participants with mild to moderate knee osteoarthritis were recruited. Under one-on-one instruction by an experienced TC master, each participant learned how to correctly perform the 24-form TC movements. Participants’ full-body kinematic and kinetic data was collected during walking trials and performance of the respective TC forms. Their dynamic stability was calculated in both sagittal and frontal planes and compared between each TC form and regular walking.ResultsThe results indicate that dynamic stability in both planes significantly varies among forms. Moreover, some forms pose a greater challenge to dynamic stability in comparison to others. The most challenging TC forms are Form 8 for stability in the sagittal plane and Form 10 in the frontal plane. Among all forms, Form 1 appears to be the least challenging.SignificanceOur findings could provide foundational information to identify the best TC forms for optimizing the effectiveness of TC-based fall prevention interventions.     

Do No Harm: A Multifactorial Approach to Preventing Emergency Department Falls—A Quality Improvement Project

IntroductionPatient falls in the emergency department are a unique patient safety issue because of the often challenging nature of the environment. As there are a variety of potential causative factors for patient falls in the emergency department, this project employed a multifactorial approach to prevent patient falls in a Level 1 trauma center emergency department (adult only) in an urban tertiary care teaching hospital.MethodsThis project was a single-unit quality improvement intervention that compared postintervention monthly unit-level data to historic monthly rates on the same unit. The intervention was multifaceted with patient-level, nurse-level, and unit-level interventions employed. A task force was convened to review and identify specific departmental gaps related to fall prevention, complete a retrospective review of departmental patient falls to determine causative factors, and implement interventions to reduce ED falls. A comprehensive program consisting of an ED-specific fall risk assessment tool, remote video monitoring (RVM), stretcher alarms, and a robust patient safety culture, among other interventions, was implemented. Patient falls and falls with injuries were tracked as an outcome measure.ResultsAfter data driven analysis of causation, selection of key interventions, staff education, and sustained focus for 2 years, the department experienced a 27% decrease in falls and a 66% decrease in falls with injuries.DiscussionA multifactorial approach was an effective strategy to decrease patient falls in the emergency department.     

Systematic review and meta-analysis of fear of falling and fall-related efficacy in a widely disseminated community-based fall prevention program

BackgroundFear of falling restricts mobility and increases fall risk among older adults. Fall-related efficacy (i.e. the confidence to perform activities without falling), a construct related to fear of falling, has also been associated with active living and fall prevention. This study statistically synthesized the program effects of A Matter of Balance Volunteer Lay Leader (AMOB/VLL) model, designed to improve fall-related efficacy and promote daily activities among community-dwelling older adults.MethodsResearch articles and doctoral dissertations that examined the effect of the AMOB/VLL on fear of falling and fall-related efficacy were searched from multiple databases. A random effects model was used to compute mean weighted effect sizes, 95 % CIs, and heterogeneity (I²). Bias was examined through a funnel plot and Egger’s test. Factors associated with heterogeneity were also explored.ResultsSeventeen AMOB/VLL studies involving 3,860 participants were identified. The pooled effects of the 13 studies with sufficient information for effect size calculation, were −0.29 (95 % CI: −0.40, −0.19) for fear of falling and 0.51 (95 % CI: 0.42, 0.60) for fall-related efficacy. Effect sizes differed partially due to outcome measures of fall-related efficacy. Covariate adjustment and study quality were not associated with differences in effect sizes. No substantial evidence of asymmetry and publication bias was found.ConclusionThis study provides evidence supporting AMOB/VLL as an effective intervention for reducing fear of falling and improving fall-related efficacy. A greater consistency in outcome measures is needed to optimally capture changes in fear of falling and fall-related efficacy among community-dwelling older adults.     

Accelerations relevant to blunt trauma: theory and data

Maximum acceleration and the Head Injury Criterion (HIC) are both used as indicators of likely head injury severity. A dataset has previously been published of impacts of an instrumented missile on four ground surfaces having a layer of between 0 and 16 cm of sand. The dataset is compared with recently-developed theory that predicts power-function dependence of maximum acceleration and HIC on drop height. That prediction was supported by the data. The surfaces differed in respect of the exponents estimated.     

Sleep quality is associated with walking under dual-task,but not single-task performance

ObjectivesThe objective of this study was to assess the relationship between sleep behavior and gait performance under single-task (ST) and dual-task (DT) walking conditions in community- dwelling older adults.MethodsWalking under ST and DT conditions was evaluated in 34 community-dwelling older adults, 64.7% women, mean age 71.5 (SD ± 5.8). Gait-speed and gait-variability data were collected using the OPAL wearable sensors of the Mobility Lab. Sleep behavior (sleep efficiency [SE] and sleep latency [SL]) was assessed using actigraphy, over 5 consecutive nights.ResultsLower SE was associated with decreased gait speed and increased stride-length variability during DT (rs = 0.35; p = 0.04; rs = −0.36; p = 0.03, respectively), whereas longer SL was associated with increased stride-length variability during DT (rs = 0.38; p = .03). After controlling for age and cognition, SE accounted for 24% and 33% of the variability in stride length and stride time. No associations were found between sleep and gait measures under ST walking.ConclusionsLower SE is associated with decreased gait speed and increased gait variability under DT conditions that are indicative of an increased risk for falls in older adults. Our findings support clinical recommendations to incorporate the evaluation of sleep quality in the context of risk assessment for falls.     

How to implement guidelines and models of care

In subjects older than 50 years, the presence of clinical risk factors (CRFs) for fractures or a recent fracture is the cornerstone for case finding. In patients who are clinically at high short- and long-term risk of fractures (those with a recent clinical fracture or with multiple CRFs), further assessment with bone mineral density (BMD) measurement using dual-energy absorptiometry (DXA), imaging of the spine, fall risk evaluation and laboratory examination contributes to treatment decisions according to the height and modifiability of fracture risk. Treatment is available with anti-resorptive and anabolic drugs, and from the start of treatment a lifelong strategy is needed to decide about continuous, intermittent, and sequential therapy. Implementation of guidelines requires further initiatives for improving case finding, public awareness about osteoporosis and national policies on reimbursement of assessment and therapy.