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Chatagnon T, Olivier AH, Hoyet L, Pettré J, Pontonnier C. Stepping strategies of young adults undergoing sudden external perturbation from different directions. J Biomech 2023; 157:111703. [PMID: 37451207 DOI: 10.1016/j.jbiomech.2023.111703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 07/18/2023]
Abstract
Stepping strategies following external perturbations from different directions is investigated in this work. We analysed the effect of the perturbation angle as well as the level of awareness of individuals and characterised steps out of the sagittal plane between Loaded Side Steps (LSS), Unloaded Medial Steps (UMS) and Unloaded Crossover Steps (UCS). A novel experimental paradigm involving perturbations in different directions was performed on a group of 21 young adults (10 females, 11 males, 20-38 years). Participants underwent 30 randomised perturbations along 5 different angles with different levels of awareness of the upcoming perturbations (with and without wearing a sensory impairment device) for a total of 1260 recorded trials. Results showed that logistic models based on the minimal values of the Margin of Stability (MoS) or on the minimal values of the Time to boundary (Ttb) performed the best in the sagittal plane. However, their accuracy stayed above 79% regardless of the perturbation angle or level of awareness. Regarding the effect of the experimental condition, evidences of different balance recovery behaviours due to the variation of perturbation angles were exposed, but no significant effect of the level of awareness was observed. Finally, we proposed the Distance to Foot boundary (DtFb) as a relevant quantity to characterise the stepping strategies in response to perturbations out of the sagittal plane.
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Taylor S, Toye F, Donovan-Hall M, Barker K. Past the tipping point: a qualitative study of the views and experiences of men with haemophilia regarding mobility, balance, and falls. Disabil Rehabil 2022; 44:7237-7245. [PMID: 34651530 DOI: 10.1080/09638288.2021.1988731] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE The life expectancy of people with haemophilia is increasing due to improved medical care. This improvement is accompanied by the co-morbidities of ageing, which include musculoskeletal degeneration and the associated effect on proprioception and balance. This study aims to explore the views and everyday experiences of those living with haemophilia regarding this. MATERIALS AND METHODS Nine people with moderate or severe haemophilia aged 43-58 years participated in semi-structured interviews and thematic analysis was used to examine the data. RESULTS Participants described pain and reduced movement in joints as a result of repeated bleeds, which caused problems with mobility and balance. Constant vigilance of their surroundings together with the potential consequences of bleeds caused continual worry. Participants were resourceful in their strategies to cope with the effects of haemophilia, to reduce pain and to minimise the risk of falling. However, participants felt stigmatised because of their condition. CONCLUSION People with haemophilia have difficulties with their mobility and balance that can increase their risk of falling. Healthcare professionals need to understand and address the physical and psycho-social factors that contribute to the risk of falls. A multi-disciplinary approach to devise effective strategies to counteract and monitor the risk of falls would be useful.Implications for RehabilitationHealthcare professionals should identify movements that are fearful and work on ways to increase confidence and ability to perform these.Healthcare professionals need to identify the recovery strategies used to maintain balance and build these movements into home exercise programmes.Effective pain reduction strategies, both pharmacological and non-pharmacological, need to be investigated and optimised.Footwear choice has implications for both pain reduction and balance and should be discussed in routine reviews.Optimising vision would maximise visual input to aid balance.
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Affiliation(s)
- Stephanie Taylor
- Oxford Haemophilia and Thrombosis Centre, Oxford University Hospital NHS Foundation Trust, UK
| | - Francine Toye
- Physiotherapy Research Unit, Nuffield Orthopaedic Centre, Oxford University Hospital NHS Foundation Trust, UK
| | | | - Karen Barker
- Physiotherapy Research Unit, Nuffield Orthopaedic Centre, Oxford University Hospital NHS Foundation Trust, UK.,Nuffield Department of Orthopaedics and Musculoskeletal Sciences (NDORMS), University of Oxford, Oxford, UK
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3
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Batcir S, Shani G, Shapiro A, Melzer I. Characteristics of step responses following varying magnitudes of unexpected lateral perturbations during standing among older people - a cross-sectional laboratory-based study. BMC Geriatr 2022; 22:400. [PMID: 35524172 PMCID: PMC9078012 DOI: 10.1186/s12877-022-03080-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 04/20/2022] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION The inability to recover from unexpected lateral loss of balance may be particularly relevant to the problem of falling. AIM We aimed to explore whether different kinematic patterns and strategies occur in the first recovery step in single-step trials in which a single step was required to recover from a fall, and in multiple-step trials in which more than one step was required to recover from a fall. In addition, in the multiple-step trials, we examined kinematic patterns of balance recovery where extra steps were needed to recover balance. METHODS Eighty-four older adults (79.3 ± 5.2 years) were exposed to unannounced right/left perturbations in standing that were gradually increased to trigger a recovery stepping response. We performed a kinematic analysis of the first recovery step of all single-step and multiple-step trials for each participant and of total balance recovery in the multiple-step trial. RESULTS Kinematic patterns and strategies of the first recovery step in the single-step trials were significantly dependent on the perturbation magnitude. It took a small, yet significantly longer time to initiate a recovery step and a significantly longer time to complete the recovery step as the magnitude increased. However, the first recovery step in the multiple-step trials showed no significant differences between different perturbation magnitudes; while, in total balance recovery of these trials, we observed a small, yet significant difference as the magnitude increased. CONCLUSIONS At relatively low perturbation magnitudes, i.e., single-step trials, older adults selected different first stepping strategies and kinematics as perturbation magnitudes increased, suggesting that this population activated pre-planned programs based on the perturbation magnitude. However, in the first recovery step of the multiple-step trials, i.e., high perturbation magnitudes, similar kinematic movement patterns were used at different magnitudes, suggesting a more rigid, automatic behavior, while the extra-steps were scaled to the perturbation magnitude. This suggest that older adults activate pre-planned programs based on the magnitude of the perturbation, even before the first step is completed..
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Affiliation(s)
- Shani Batcir
- Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Guy Shani
- Department of Information Systems, Faculty of Engineering Sciences, Ben-Gurion University, Beer-Sheva, Israel
| | - Amir Shapiro
- Department of Mechanical Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Itshak Melzer
- Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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Xu JC, Silvano AP, Keller A, Krašna S, Thomson R, Klug C, Linder A. Identifying and Characterizing Types of Balance Recovery Strategies Among Females and Males to Prevent Injuries in Free-Standing Public Transport Passengers. Front Bioeng Biotechnol 2021; 9:670498. [PMID: 34291040 PMCID: PMC8287834 DOI: 10.3389/fbioe.2021.670498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 06/11/2021] [Indexed: 11/26/2022] Open
Abstract
Free-standing passengers on public transport are subjected to perturbations during non-collision incidents caused by driver maneuvers, increasing the risk of injury. In the literature, the step strategy is described as a recovery strategy during severe perturbations. However, stepping strategies increase body displacement, ultimately subjecting passengers to higher risk of impacts and falls on public transport. This study investigates the influence of different recovery strategies on the outcome of balance recovery of free-standing public transport passengers, challenged in postural balance by the non-uniform vehicle dynamics. From high-speed video recordings, a qualitative investigation of the balance responses of volunteer participants in a laboratory experiment was provided. On a linearly moving platform, 24 healthy volunteers (11 females and 13 males) were subjected to perturbation profiles of different magnitude, shape and direction, mimicking the typical acceleration and deceleration behavior of a bus. A methodology categorizing the balancing reaction to an initial strategy and a recovery strategy, was used to qualitatively identify, characterize and, evaluate the different balance strategies. The effectiveness of different strategies was assessed with a grading criterion. Statistical analysis based on these ordinal data was provided. The results show that the current definition in the literature of the step strategy is too primitive to describe the different identified recovery strategies. In the volunteers with the most successful balancing outcome, a particularly effective balance recovery strategy not yet described in the literature was identified, labeled the fighting stance. High jerk perturbations seemed to induce faster and more successful balance recovery, mainly for those adopting the fighting stance, compared to the high acceleration and braking perturbation profiles. Compared to the pure step strategy, the characteristics of the fighting stance seem to increase the ability to withstand higher perturbations by increasing postural stability to limit body displacement.
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Affiliation(s)
- Jia-Cheng Xu
- Swedish National Road and Transport Research Institute, Linköping, Sweden
| | - Ary P Silvano
- Swedish National Road and Transport Research Institute, Linköping, Sweden
| | | | - Simon Krašna
- Faculty of Mechanical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Robert Thomson
- Mechanics and Maritime Science, Chalmers University of Technology, Gothenburg, Sweden
| | - Corina Klug
- Vehicle Safety Institute, Graz University of Technology, Graz, Austria
| | - Astrid Linder
- Swedish National Road and Transport Research Institute, Linköping, Sweden.,Mechanics and Maritime Science, Chalmers University of Technology, Gothenburg, Sweden
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Borrelli J, Creath R, Gray VL, Rogers MW. Untangling biomechanical differences in perturbation-induced stepping strategies for lateral balance stability in older individuals. J Biomech 2020; 114:110161. [PMID: 33316540 DOI: 10.1016/j.jbiomech.2020.110161] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 11/18/2020] [Accepted: 11/27/2020] [Indexed: 11/16/2022]
Abstract
When recovering balance from a lateral perturbation, younger adults tend to stabilize balance with a single lateral sidestep while older adults often take multistep responses. Using multiple steps to recover balance is consistently associated with increased fall risk, altered body center of mass (CoM) control and instability. The aim of this study was to compare the spatio-temporal stepping characteristics and the margin of stability (MoS) of single lateral sidesteps (LSS1) with the first and second steps of a two-step protective step sequence. Two-step sequences begin with either a cross-over step to the front or back, or a medial step followed by a lateral sidestep. Seventy-one older adults received random lateral waist-pull perturbations to either side. We hypothesized that LSS1 would be more stable (larger MoS) than either step in a two-step sequence. With some exceptions, utilizing a two-step sequence was associated with a reduced CoM velocity and distance between the base of support and CoM and decreased stability in the frontal plane following limb loading of the first and second step. There were no differences in the time available to arrest the extrapolated CoM at the end of a single lateral sidestep or the final step of a two-step sequence. Two-step sequences involving a cross-over step include more complex stepping trajectories and also challeng stability in the sagittal plane requiring a multidimensional balance correction. These results indicate important step type differences in center of mass control in recovering balance with a single lateral sidestep as opposed to a two-step sequence among older adults.
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Affiliation(s)
- J Borrelli
- University of Maryland School of Medicine, MD, USA.
| | | | - V L Gray
- University of Maryland School of Medicine, MD, USA
| | - M W Rogers
- University of Maryland School of Medicine, MD, USA.
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Batcir S, Shani G, Shapiro A, Alexander N, Melzer I. 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. BMC Geriatr 2020; 20:249. [PMID: 32689965 PMCID: PMC7372810 DOI: 10.1186/s12877-020-01650-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 07/13/2020] [Indexed: 11/10/2022] Open
Abstract
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 ).
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Affiliation(s)
- Shani Batcir
- Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Schwartz Movement Analysis & Rehabilitation Laboratory, Department of Physical Therapy, Recanati School for Community Health Professions, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O.B. 653, 84105, Beer-Sheva, Israel
| | - Guy Shani
- Department of Information Systems, Faculty of Engineering Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Amir Shapiro
- Department of Mechanical Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Neil Alexander
- Division of Geriatric and Palliative Medicine, Department of Internal Medicine, University of Michigan, Veterans Affairs Ann Arbor Health Care System Geriatrics Research Education and Clinical Center (GRECC), Ann Arbor, MI, USA
| | - Itshak Melzer
- Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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Nachmani H, Shani G, Shapiro A, Melzer I. Characteristics of First Recovery Step Response following Unexpected Loss of Balance during Walking: A Dynamic Approach. Gerontology 2020; 66:362-370. [PMID: 32069450 DOI: 10.1159/000505649] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 12/30/2019] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Many falls in older adults occur during walking and result in lateral falls. The ability to perform a recovery step after balance perturbation determines whether a fall will occur. AIM To investigate age-related changes in first recovery step kinematics and kinematic adaptations over a wide range of lateral perturbation magnitudes while walking. METHODS Thirty-five old (78.5 ± 5 years) and 19 young adults (26.0 ± 0.8 years) walked at their preferred walking speed on a treadmill. While walking, the subjects were exposed to announced right/left perturbations in different phases of the gait cycle that were gradually increased in order to trigger a recovery stepping response. The subjects were instructed to react naturally and try to avoid falling. Kinematic analysis was performed to analyze the first recovery step parameters (e.g., step initiation, swing duration, step length, and the estimated distance of the center of mass from the base of support [dBoS]). RESULTS Compared with younger adults, older adults displayed a significantly lower step threshold and at lower perturbation magnitudes during the experiment. Also, they showed slower compensatory step initiation, shorter step length, and dBoS with similar step recovery times. As the perturbation magnitudes increased, older adults showed very small, yet significant, decreases in the timing of the step response, and increased their step length. Younger adults did not show changes in the timing of stepping, with a tendency toward a significant increase in step length. CONCLUSIONS First compensatory step performance is impaired in older adults. In terms of the dynamic approach, older adults were more flexible, i.e., less automatic, while younger adults displayed more automatic behavior.
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Affiliation(s)
- Hadas Nachmani
- Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Guy Shani
- Department of Information Systems, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Amir Shapiro
- Department of Mechanical Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Itshak Melzer
- Department of Physical Therapy, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel,
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8
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Age-related changes in the capacity to select early-onset upper-limb reactions to either recover balance or protect against impact. Exp Gerontol 2019; 125:110676. [DOI: 10.1016/j.exger.2019.110676] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/21/2019] [Accepted: 07/29/2019] [Indexed: 11/18/2022]
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Ribeiro de Souza C, Betelli MT, Takazono PS, de Oliveira JÁ, Coelho DB, Duysens J, Teixeira LA. Evaluation of balance recovery stability from unpredictable perturbations through the compensatory arm and leg movements (CALM) scale. PLoS One 2019; 14:e0221398. [PMID: 31461500 PMCID: PMC6713348 DOI: 10.1371/journal.pone.0221398] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 08/06/2019] [Indexed: 11/30/2022] Open
Abstract
Following unpredictable large-magnitude stance perturbations diverse patterns of arm and leg movements are performed to recover balance stability. Stability of these compensatory movements could be properly estimated through qualitative evaluation. In the present study, we present a scale for evaluation of compensatory arm and leg movements (CALM) in response to unpredictable displacements of the support base in the mediolateral direction. We tested the CALM scale for intra- and inter-rater reliability, correlation with kinematics of arm and leg movement amplitudes, and sensitivity to mode (rotation, translation and combined) and magnitude (velocity) of support base displacements, and also to perturbation-based balance training. Results showed significant intra- and inter-rater coefficients of agreement, ranging from moderate (0.46–0.53) for inter-rater reliability in the arm and global scores, to very high (0.87–0.99) for inter-rater leg scores and all intra-rater scores. Analysis showed significant correlation values between scale scores and the respective movement amplitudes both for arm and leg movements. Assessment of sensitivity revealed that the scale discriminated the responses between perturbation modes, platform velocities, in addition to higher balance recovery stability as a result of perturbation-based balance training. As a conclusion, the CALM scale was shown to provide adequate integrative evaluation of compensatory arm and leg movements for balance recovery stability after challenging stance perturbations, with potential application in fall risk prediction.
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Affiliation(s)
- Caroline Ribeiro de Souza
- Human Motor Systems Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil Centre for Engineering, Modeling and Applied Social Sciences (CECS), Federal University of ABC, São Paulo, Brazil
- * E-mail:
| | - Marina Torres Betelli
- Human Motor Systems Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil Centre for Engineering, Modeling and Applied Social Sciences (CECS), Federal University of ABC, São Paulo, Brazil
| | - Patrícia Sayuri Takazono
- Human Motor Systems Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil Centre for Engineering, Modeling and Applied Social Sciences (CECS), Federal University of ABC, São Paulo, Brazil
| | - Julia Ávila de Oliveira
- Human Motor Systems Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil Centre for Engineering, Modeling and Applied Social Sciences (CECS), Federal University of ABC, São Paulo, Brazil
| | - Daniel Boari Coelho
- Centre for Engineering, Modeling and Applied Social Sciences (CECS), Federal University of ABC, São Paulo, Brazil
| | - Jacques Duysens
- Department of Movement Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Catholic University of Leuven, Leuven, Belgium
| | - Luis Augusto Teixeira
- Human Motor Systems Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil Centre for Engineering, Modeling and Applied Social Sciences (CECS), Federal University of ABC, São Paulo, Brazil
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Perturbation-evoked lateral steps in older adults: Why take two steps when one will do? Clin Biomech (Bristol, Avon) 2019; 63:41-47. [PMID: 30825811 PMCID: PMC6501204 DOI: 10.1016/j.clinbiomech.2019.02.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 01/28/2019] [Accepted: 02/22/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND Hip fractures in older adults often result from a fall in the lateral direction. While younger adults tend to recover balance from a lateral perturbation with a single lateral sidestep, older adults are prone to multistep responses which are associated with an increased fall risk. This study compared the stepping characteristics and stability of single and multistep responses to lateral perturbation in healthy older adults. METHODS Eighty-four older adults received lateral waist-pull perturbations to either side. Spatio-temporal stepping characteristics and balance stability were quantified. FINDINGS Fewer steps were taken to recover balance when the first step was a lateral sidestep. The stability margin of single lateral sidesteps was greater than medial sidesteps and cross-over steps to the back but not significantly different from single cross-over steps to the front at step termination. Single step responses were more stable than multistep responses at step termination and at step initiation for lateral sidesteps and cross-over steps to the front. The decreased stability of multistep responses was attributed to an increased center of mass velocity and a smaller distance between the center of mass and base-of-support at step termination. INTERPRETATION Although lateral sidesteps result in fewer steps than cross-over steps to the front, the stability margin was not significantly different at step termination. These results suggest difficulty terminating center of mass motion and/or inefficient center of mass control differentiates single and multistep responses. Future studies should investigate perturbation training and/or hip abductor muscle conditioning as a means of improving compensatory stepping reactions.
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11
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Inacio M, Creath R, Rogers MW. Effects of aging on hip abductor-adductor neuromuscular and mechanical performance during the weight transfer phase of lateral protective stepping. J Biomech 2018; 82:244-250. [PMID: 30455060 DOI: 10.1016/j.jbiomech.2018.10.040] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 10/05/2018] [Accepted: 10/28/2018] [Indexed: 12/01/2022]
Abstract
Aging brings about challenges in the ability to recover balance through protective stepping, especially in the lateral direction. Previous work has suggested that lateral protective stepping during weight transfer may be affected by impaired muscle composition and performance of the hip abductors (AB) in older adults. Hence, this study investigated the influence of hip abductor-adductor (AB-AD) neuromuscular performance on the weight transfer phase of lateral protective stepping in younger and older adults. Healthy younger (n = 15) and older adults (n = 15) performed hip AB-AD isometric maximal voluntary contractions (IMVC). Lateral balance perturbations were applied via motorized waist-pulls. Participants were instructed to recover their balance using a single lateral step. Kinetic, kinematic and electromyographic (EMG) data were analyzed during the weight transfer phase. In the hip IMVC task, older adults showed reduced peak AB-AD torque, AB rate of torque development and AB-AD rate of EMG neuromuscular activation (RActv). During the lateral balance perturbations, older individuals had a lower incidence of lateral steps, reduced hip AB-AD RActv and delayed weight transfer. However, several outcomes were larger in the older group, such as, center of mass momentum at step onset, step-side peak rate of vertical force development, hip AB net joint torque, and power. Although older adults had greater hip muscular output during the weight transfer phase, their lateral balance recovery was still impaired. The reduced maximal hip AB-AD capacity, especially RActv, may have been a greater contributor to this impairment, as it affects the ability to generate rapid force, crucial for balance recovery.
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Affiliation(s)
- Mario Inacio
- University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Rob Creath
- University of Maryland School of Medicine, Baltimore, MD, USA
| | - Mark W Rogers
- University of Maryland School of Medicine, Baltimore, MD, USA
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