Compensatory stepping responses during real-life falls in older adults

Role of the Upper Limb in Limiting Head Impact During Laboratory-Induced Falls in at Fall-Risk Older Adults

BACKGROUND

Fall-related head impact is the leading cause of traumatic brain injury in older adults. There is limited understanding of factors related to fall-related head impact. This investigation examined characteristics of upper limb movements during standing-height falls and examined their association with fall-related head impact in older adults at risk for falls.

METHODS

Older adults (n = 29) at risk for fall-related injuries underwent experimentally induced falls in multiple directions (backwards and sideways). To characterize the upper limb movements and their association with head impact, a standardized analysis tool was used to analyze a total of 164 video-recorded falls. The association between upper limb movements (and their characteristics) and head impact was analyzed through logistic regression.

RESULTS

Nearly 80% of falls involved upper limb movements. Absence of upper limb movements significantly increased head impact odds by approximately 4-fold. The odds of head impact were reduced in falls with energy absorption at the forearm (0.013-fold) and upper arm (0.018-fold), compared to falls without upper limb energy absorption. Backwards falls showed significantly higher odds of head impact (more than 4-fold).

CONCLUSIONS

Upper limb movements are common during fall descent and are associated with lower odds of experiencing head impact. Energy absorption with the upper limb seems to be an important protective mechanism. Future work should explore if these movements can be augmented with targeted training.

Interactions during falls with environmental objects: evidence from real-life falls in long-term care captured on video

BACKGROUND

Falls are the leading cause of injuries in older adults. Environmental objects (such as furniture, walls, and handrails) may act as hazards or facilitators to balance maintenance and safe landing. There is lack of objective evidence on how older adults interact with objects during falls. We addressed this gap by characterizing body part contacts with objects other than the floor during real-life falls in long-term care.

METHODS

We analyzed videos of 1759 falls experienced by 584 residents to characterize the prevalence of contacts with objects before, during, and after fall initiation. Using generalized estimating equations, we compared the prevalence of falls with versus without contact to objects after fall initiation. Using linear mixed models, we tested for differences across body parts in the probability of contacting objects after fall initiation.

RESULTS

In nearly one-third of falls, interactions with objects (e.g., trips over objects, loss of support with objects) or with other people (e.g., being pushed by another person) had a primary role in causing imbalance and initiating the fall. After fall initiation, participants contacted objects in 60% of falls, with intentional hand contacts to objects via reach-to-grasp or bracing being the most common type of interaction (Probability ± SE = 0.32 ± 0.01), followed by unintentional impacts to the torso (0.21 ± 0.01) and head (0.16 ± 0.01). Intentional hand contact to an object was more common during forward than backward falls (p < 0.001), while head and torso contacts to objects were more common during backward and sideways falls than forward falls (multiple p values ≤ 0.003). The hand most often contacted chairs, wheelchairs or couches, followed by tables or counters, walls, other people, walkers, and handrails. The head, torso, and shoulder most often contacted a wall.

CONCLUSIONS

Most falls in long-term care involved contacts with objects other than the ground, indicating that complex environments often accompany falls in long-term care. Higher probabilities of intentional hand contacts in forward falls, versus unintentional head and torso impacts in backward and sideways falls may reflect the influence of being able to visualize and adjust one's falling patterns to nearby objects.

Reduced adaptability to balance perturbations in older adults with probable cognitive impairment after a severe fall

Falls in older individuals often result from unexpected balance disturbances during walking, necessitating the analysis of recovery strategies for effective falls prevention. This becomes particularly crucial for individuals with cognitive impairment, who face a higher fall risk compared to cognitively healthy adults. Hence, our study aimed to compare the recovery response to standardized walking perturbations on a treadmill between older adults with cognitive impairment and cognitively healthy older adults. 36 individuals with a recent history of a severe fall, leading to an emergency department visit without subsequent admission, were stratified into two groups (with and without probable cognitive impairment) based on scores of the Montreal Cognitive Assessment. Recovery performance was quantified using force plate data from a perturbation treadmill (M-Gait, Motek Medical B.V., Amsterdam, the Netherlands), specifically evaluating the number of steps needed to restore step length and width to pre perturbation baseline across two trials of nine different perturbations. Individuals with cognitive impairment (n = 18, mean age: 74.7) required significantly (p = 0.045, Cohen's d = 0.69) more steps to recover total steps after perturbations compared to cognitively healthy individuals (n = 18, mean age: 69.7). While step width recovery was similar between the groups, those with probable cognitive impairment required significantly more steps to recover their step length (p = 0.039, Cohen's d = 0.72). Thus, our findings indicate that older adults with probable cognitive impairment manifest inferior gait adaptability, especially in adapting step length, potentially underscoring a critical aspect for effective falls prevention in this population.

Influences of backpack loading on recovery from anterior and posterior losses of balance: An exploratory investigation

Backpacks are common devices for carrying external posterior loads. However, relatively little is known about how these external loads affect the ability to recover from balance loss. In this exploratory investigation, 16 young adults (8 female, 8 male) performed forward and backward lean-and-release balance recovery trials, while wearing a backpack that was unloaded or loaded (at 15% of individual body weight). We quantified the effects of backpack loading on balance recovery in terms of maximum recoverable lean angles, center-of-mass kinematics, and temporal-spatial stepping characteristics. Mean values of maximum lean angles were 20° and 9° in response to forward and backward perturbations, respectively. These angles significantly decreased when wearing the additional load for only backward losses of balance. During backward losses of balance, the additional load decreased peak center-of-mass velocity and increased acceleration by ∼10 and 18% respectively, which was accompanied by ∼5% faster stepping responses and steps that were ∼9% longer, 11% higher, and had an ∼10% earlier onset. Thus, wearing a backpack decreases backward balance recovery ability and changes backward recovery stepping characteristics.

Footwear and Falls in Long-Term Residential Aged Care Facilities: An Analysis of Video Capture Data

INTRODUCTION

Several footwear characteristics have been shown to affect balance and gait patterns and may therefore influence the risk of falling in older adults. However, attributing a link between footwear and falls is inherently difficult as it often relies on self-report which may be inaccurate.

METHODS

Archival video recordings of falls that occurred in two long-term residential aged care facilities were initially screened to determine whether the footwear worn at the time (barefoot, socks, slippers/sandals, or shoes) could be documented. These falls were then independently evaluated by three additional assessors and a meeting was held to obtain consensus in relation to whether the footwear could have potentially contributed to the fall, and what mechanism may have been responsible. Cross-tabulations were performed in relation to footwear type and fall characteristics (proposed mechanism and fall direction).

RESULTS

There were 300 falls experienced by 118 older adults aged 58 years-98 years (mean age 82.8 years, SD 7.6). Of these falls, footwear could be ascertained in 224 (75%). After the consensus meeting, the proportion of falls considered to be potentially related to footwear was 40 (18%). The likelihood of footwear contributing to the fall was highest when participants were wearing socks (14/19 falls; 74% of all footwear-related falls), followed by being barefoot (2/6 falls; 33%), wearing slippers/sandals (17/100 falls; 17%), and wearing shoes (7/99 falls, 7%).

CONCLUSION

Footwear could be a potential contributor to a substantial number of falls in residential aged care. Wearing socks would appear to place an older person at risk of future falls and should therefore be avoided in this population.

Classification and Definitions of Compensatory Protective Step Strategies in Older Adults: A Scoping Review

BACKGROUND

The risk for an unexpected fall can be due to increasing age, health conditions, and loss of cognitive, sensory, or musculoskeletal functions. Falls have personal and economic consequences in many countries. Different disturbances can occur during gait, such as tripping, slipping, or other unexpected circumstances that can generate a loss of balance. The strategies used to recover balance depend on many factors, but selecting a correct response strategy influences the success of balance recovery.

OBJECTIVES

(1) To collect and clarify the definitions of compensatory protective step strategies to recover balance in older adults; (2) to identify the most used methods to induce loss of balance; and (3) to identify the most used spatiotemporal variables in analyzing these actions.

METHODS

The present review has followed the PRISMA guideline extension for Scoping Review (PRISMA-ScR) and the phases proposed by Askery and O'Malley. The search was conducted in three databases: PubMed, Web of Science, and Scopus.

RESULTS

A total of 525 articles were identified, and 53 studies were included. Forty-five articles were quasi-experimental studies, six articles were randomized controlled trials, and two studies had an observational design. In total, 12 compensatory protective step strategies have been identified.

CONCLUSIONS

There are 12 compensatory protective step strategies: lowering and elevating strategy, short- and long-step strategy, backward and forward stepping for slip, single step, multiple steps, lateral sidesteps or loaded leg sidestep unloaded leg sidestep, crossover step (behind and front), and medial sidestep. To standardize the terminology applied in future studies, we recommend collecting these strategies under the term of compensatory protective step strategies. The most used methods to induce loss of balance are the tether-release, trip, waist-pull, and slip methods. The variables analyzed by articles are the number of steps, the acceleration phase and deceleration phase, COM displacement, the step initiation or step duration, stance phase time, swing phase time and double-stance duration, stride length, step length, speed step, speed gait and the type of step.

Involvement of Older Adults, the Golden Resources, as a Primary Measure for Fall Prevention

Falls remain the second leading cause of injury-related deaths worldwide; therefore, longstanding practical fall-prevention efforts are needed. Falls can also lead to a reduction in independence and quality of life among older adults. Fall-prevention research has found that early prevention promotes a prolonged independence. However, it remains unknown which intervention is most beneficial for early prevention and how these interventions should be implemented for long-term effects. In addition, the present and future burden on social and healthcare services contributes to a gap in needs and requires an evidence-based fall prevention. Research suggests that strength, balance, and functional training are effective in reducing falls and fall-related injuries. Such training could greatly impacting independence. Fear of falling and strategies for managing falls are the suggested components to be included when evaluating fall-prevention programs. Thus, the preservation of physical functions is highly relevant for both independence and quality of life. It also contributes to psychological and social well-being, which are important factors for enabling individuals to stay at home for as long as possible. To meet future challenges associated with the expected increase in the older population, older adults should be viewed as a golden resource. With assistance from professionals and researchers, they can learn and gain the ability to institute fall-prevention programs in their own environments. These environments are primarily beyond the responsibilities of the healthcare sector. Therefore, programs comprising current knowledge about fall prevention should be developed, evaluated, and implemented with older adults by using a "train-The-trainer" approach, where a natural collaboration is established between civil society and/or volunteers, healthcare professionals, and researchers. For sustainable and effective fall-prevention programs, a co-design and early collaborative approach should be used in the natural environment, before social and healthcare services are required.

Suppressing a Blocked Balance Recovery Step: A Novel Method to Assess an Inhibitory Postural Response

Stepping to recover balance is an important way we avoid falling. However, when faced with obstacles in the step path, we must adapt such reactions. Physical obstructions are typically detected through vision, which then cues step modification. The present study describes a novel method to assess visually prompted step inhibition in a reactive balance context. In our task, participants recovered balance by quickly stepping after being released from a supported forward lean. On rare trials, however, an obstacle blocked the stepping path. The timing of vision relative to postural perturbation was controlled using occlusion goggles to regulate task difficulty. Furthermore, we explored step suppression in our balance task related to inhibitory capacity measured at the hand using a clinically feasible handheld device (ReacStick). Our results showed that ReacStick and step outcomes were significantly correlated in terms of successful inhibition (r = 0.57) and overall reaction accuracy (r = 0.76). This study presents a novel method for assessing rapid inhibition in a dynamic postural context, a capacity that appears to be a necessary prerequisite to a subsequent adaptive strategy. Moreover, this capacity is significantly related to ReacStick performance, suggesting a potential clinical translation.