1
|
Stief F, Sohn A, Vogt L, Meurer A, Kirchner M. Characterization of Postural Sway in Women with Osteoporosis and a Control Group by Means of Linear and Nonlinear Methods. Bioengineering (Basel) 2023; 10:bioengineering10040403. [PMID: 37106590 PMCID: PMC10135765 DOI: 10.3390/bioengineering10040403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/13/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
The mechanisms underlying the altered postural control and risk of falling in patients with osteoporosis are not yet fully understood. The aim of the present study was to investigate postural sway in women with osteoporosis and a control group. The postural sway of 41 women with osteoporosis (17 fallers and 24 non-fallers) and 19 healthy controls was measured in a static standing task with a force plate. The amount of sway was characterized by traditional (linear) center-of-pressure (COP) parameters. Structural (nonlinear) COP methods include spectral analysis by means of a 12-level wavelet transform and a regularity analysis via multiscale entropy (MSE) with determination of the complexity index. Patients showed increased body sway in the medial–lateral (ML) direction (standard deviation in mm: 2.63 ± 1.00 vs. 2.00 ± 0.58, p = 0.021; range of motion in mm: 15.33 ± 5.58 vs. 10.86 ± 3.14, p = 0.002) and more irregular sway in the anterior–posterior (AP) direction (complexity index: 13.75 ± 2.19 vs. 11.18 ± 4.44, p = 0.027) relative to controls. Fallers showed higher-frequency responses than non-fallers in the AP direction. Thus, postural sway is differently affected by osteoporosis in the ML and AP directions. Clinically, effective assessment and rehabilitation of balance disorders can benefit from an extended analysis of postural control with nonlinear methods, which may also contribute to the improvement of risk profiles or a screening tool for the identification of high-risk fallers, thereby prevent fractures in women with osteoporosis.
Collapse
Affiliation(s)
- Felix Stief
- Department of Orthopedics (Friedrichsheim), University Hospital, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
- Dr. Rolf M. Schwiete Research Unit for Osteoarthritis, Department of Orthopedics (Friedrichsheim), University Hospital, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
- Correspondence: ; Tel.: +49-(69)-6301-94862
| | - Anna Sohn
- Department of Orthopedics (Friedrichsheim), University Hospital, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Lutz Vogt
- Department of Sports Medicine and Exercise Physiology, Institute of Sports Sciences, Goethe University Frankfurt, 60487 Frankfurt am Main, Germany
| | - Andrea Meurer
- Department of Orthopedics (Friedrichsheim), University Hospital, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Marietta Kirchner
- Institute of Medical Biometry, University Hospital Heidelberg, 69120 Heidelberg, Germany
| |
Collapse
|
2
|
Promsri A, Haid T, Federolf P. Complexity, Composition, and Control of Bipedal Balancing Movements as the Postural Control System Adapts to Unstable Support Surfaces or Altered Feet Positions. Neuroscience 2020; 430:113-124. [DOI: 10.1016/j.neuroscience.2020.01.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/14/2020] [Accepted: 01/19/2020] [Indexed: 10/25/2022]
|
3
|
An Oculus Rift Assessment of Dynamic Balance by Head Mobility in a Virtual Park Scene: A Pilot Study. Motor Control 2019; 23:127-142. [PMID: 30518313 DOI: 10.1123/mc.2018-0001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 06/01/2018] [Accepted: 06/18/2018] [Indexed: 11/18/2022]
Abstract
Postural sway does not differentiate between balance disorders. Head kinematics within a salient, immersive environment could potentially help identifying movement patterns that are unique to vestibular dysfunction. We describe a virtual park scene, where participants are asked to avoid a virtual ball approaching their head, to target dynamic balance and quantify head movement strategy. Sixteen patients with vestibular dysfunction and 16 healthy controls were wearing the Oculus Rift and performed the "park" scene on floor and stability trainers. Significant between-group differences emerged in head path (patients rotated their head sideways more), head acceleration (controls had higher acceleration, especially on translation movements), and peak frequency (controls peaked around the frequency of the ball whereas patients were variable). Those findings demonstrated good to excellent test-retest reliability. There were no significant between-group differences in postural sway parameters. Future studies should establish norms across different levels of balance dysfunction and investigate the underlying mechanism leading to the movement strategy observed.
Collapse
|
4
|
Weighting and reweighting of visual input via head mounted display given unilateral peripheral vestibular dysfunction. Hum Mov Sci 2019; 68:102526. [PMID: 31669803 DOI: 10.1016/j.humov.2019.102526] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 09/25/2019] [Accepted: 09/25/2019] [Indexed: 12/25/2022]
Abstract
We translated a well-established laboratory paradigm to study sensory integration into a Head-Mounted-Display (HMD). In the current study, a group of 23 individuals with unilateral vestibular dysfunction and 16 age-matched controls observed moving spheres projected from the Oculus Rift. We confirmed increased visual weighting with an unstable surface and decreased visual weighting (i.e., reweighting) with increased visual amplitude. We did not observe significant differences in gains and phases between individuals with vestibular dysfunction and age-matched controls. The vestibular group increased sway in mid and high frequencies significantly more than controls with the change in surface or visual amplitude. Mild visual perturbations within HMDs carry the potential to become a useful portable assessment of postural control in individuals with vestibular disorders.
Collapse
|
5
|
Porto C, Lemos T, Ferreira AS. Analysis of the postural stabilization in the upright stance using optimization properties. Biomed Signal Process Control 2019. [DOI: 10.1016/j.bspc.2019.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
6
|
Zhu P, Wu Y, Liang J, Ye Y, Liu H, Yan T, Song R. Characterization of the Stroke-Induced Changes in the Variability and Complexity of Handgrip Force. ENTROPY 2018; 20:e20050377. [PMID: 33265466 PMCID: PMC7512896 DOI: 10.3390/e20050377] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 05/14/2018] [Accepted: 05/14/2018] [Indexed: 11/24/2022]
Abstract
Introduction: The variability and complexity of handgrip forces in various modulations were investigated to identify post-stroke changes in force modulation, and extend our understanding of stroke-induced deficits. Methods: Eleven post-stroke subjects and ten age-matched controls performed voluntary grip force control tasks (power-grip tasks) at three contraction levels, and stationary dynamometer holding tasks (stationary holding tasks). Variability and complexity were described with root mean square jerk (RMS-jerk) and fuzzy approximate entropy (fApEn), respectively. Force magnitude, Fugl-Meyer upper extremity assessment and Wolf motor function test were also evaluated. Results: Comparing the affected side with the controls, fApEn was significantly decreased and RMS-jerk increased across the three levels in power-grip tasks, and fApEn was significantly decreased in stationary holding tasks. There were significant strong correlations between RMS-jerk and clinical scales in power-grip tasks. Discussion: Abnormal neuromuscular control, altered mechanical properties, and atrophic motoneurons could be the main causes of the differences in complexity and variability in post-stroke subjects.
Collapse
Affiliation(s)
- Pengzhi Zhu
- School of Engineering, Sun Yat-sen University, Guangzhou 510275, China
- Guangdong Medical Devices Quality Surveillance and Test Institute, Guangzhou 510275, China
| | - Yuanyu Wu
- School of Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Jingtao Liang
- School of Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Yu Ye
- School of Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Huihua Liu
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510275, China
| | - Tiebin Yan
- Department of Rehabilitation Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510275, China
| | - Rong Song
- School of Engineering, Sun Yat-sen University, Guangzhou 510275, China
- Correspondence: ; Tel.: +86-20-3933-2148
| |
Collapse
|
7
|
Lubetzky AV, Harel D, Lubetzky E. On the effects of signal processing on sample entropy for postural control. PLoS One 2018; 13:e0193460. [PMID: 29494625 PMCID: PMC5832259 DOI: 10.1371/journal.pone.0193460] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 02/12/2018] [Indexed: 11/29/2022] Open
Abstract
Sample entropy, a measure of time series regularity, has become increasingly popular in postural control research. We are developing a virtual reality assessment of sensory integration for postural control in people with vestibular dysfunction and wished to apply sample entropy as an outcome measure. However, despite the common use of sample entropy to quantify postural sway, we found lack of consistency in the literature regarding center-of-pressure signal manipulations prior to the computation of sample entropy. We therefore wished to investigate the effect of parameters choice and signal processing on participants’ sample entropy outcome. For that purpose, we compared center-of-pressure sample entropy data between patients with vestibular dysfunction and age-matched controls. Within our assessment, participants observed virtual reality scenes, while standing on floor or a compliant surface. We then analyzed the effect of: modification of the radius of similarity (r) and the embedding dimension (m); down-sampling or filtering and differencing or detrending. When analyzing the raw center-of-pressure data, we found a significant main effect of surface in medio-lateral and anterior-posterior directions across r’s and m’s. We also found a significant interaction group × surface in the medio-lateral direction when r was 0.05 or 0.1 with a monotonic increase in p value with increasing r in both m’s. These effects were maintained with down-sampling by 2, 3, and 4 and with detrending but not with filtering and differencing. Based on these findings, we suggest that for sample entropy to be compared across postural control studies, there needs to be increased consistency, particularly of signal handling prior to the calculation of sample entropy. Procedures such as filtering, differencing or detrending affect sample entropy values and could artificially alter the time series pattern. Therefore, if such procedures are performed they should be well justified.
Collapse
Affiliation(s)
- Anat V Lubetzky
- Department of Physical Therapy, Steinhardt School of Culture Education and Human Development, New York University, New York, NY, United States of America
| | - Daphna Harel
- Department of Applied Statistics, Social Science and Humanities, Steinhardt School of Culture Education and Human Development, New York University, New York, NY, United States of America
| | - Eyal Lubetzky
- Courant Institute of Mathematical Sciences, New York University, New York, NY, United States of America
| |
Collapse
|
8
|
Soares SFC, Koch DB, Mochizuki L. Avaliação da musculatura flexora dos artelhos de idosos institucionalizados e comunitários: aspectos biomecânicos, mobilidade e quedas. FISIOTERAPIA E PESQUISA 2018. [DOI: 10.1590/1809-2950/17342225012018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RESUMO As mudanças morfológicas, biomecânicas e funcionais nos pés podem aumentar o risco de queda nos idosos. Os idosos institucionalizados apresentam menor mobilidade e maior risco de queda. O objetivo deste trabalho é verificar as relações das características dos pés com a mobilidade e quedas de idosos institucionalizados e ativos da comunidade. Participaram deste estudo 15 idosos institucionalizados e 15 idosos ativos da comunidade, que foram avaliados quanto à incidência de quedas e por meio do Timed Up and Go Test; presença de hálux valgo e pico de força muscular de flexores do hálux e dos artelhos pela plataforma de pressão. utilizou-se a análise de variância para comparar os grupos. Como resultado, os idosos comunitários apresentaram maior força muscular de flexores dos artelhos que os idosos institucionalizados (p<0,05) e melhor mobilidade funcional. Observou-se risco de queda nos idosos institucionalizados. O hálux valgo grau leve foi a deformidade mais comum. O teste de Pearson não mostrou correlação entre as variáveis analisadas e a incidência de quedas. Conclui-se que a força muscular de flexores dos artelhos é maior nos idosos comunitários, assim como a mobilidade funcional, quando comparados com idosos institucionalizados.
Collapse
|
9
|
Lubetzky AV, Kary EE, Harel D, Hujsak B, Perlin K. Feasibility and reliability of a virtual reality oculus platform to measure sensory integration for postural control in young adults. Physiother Theory Pract 2018; 34:935-950. [PMID: 29364733 DOI: 10.1080/09593985.2018.1431344] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Using Unity for the Oculus Development-Kit 2, we have developed an affordable, portable virtual reality platform that targets the visuomotor domain, a missing link in current clinical assessments of postural control. Here, we describe the design and technical development as well as report its feasibility with regards to cybersickness and test-retest reliability in healthy young adults. METHOD Our virtual reality paradigm includes two functional scenes ('City' and 'Park') and four moving dots scenes. Twenty-one healthy young adults were tested twice, one to two weeks apart. They completed a simulator sickness questionnaire several times per session. Their postural sway response was recorded from a forceplate underneath their feet while standing on the floor, stability trainers, or a Both Sides Up (BOSU) ball. Sample entropy, postural displacement, velocity, and excursion were calculated and compared between sessions given the visual and surface conditions. RESULTS Participants reported slight-to-moderate transient side effects. Intra-Class Correlation values mostly ranged from 0.5 to 0.7 for displacement and velocity, were above 0.5 (stability trainer conditions) and above 0.4 (floor mediolateral conditions) for sample entropy, and minimal for excursion. CONCLUSION Our novel portable VR platform was found to be feasible and reliable in healthy young adults.
Collapse
Affiliation(s)
- Anat V Lubetzky
- a Department of Physical Therapy, Steinhardt School of Culture Education and Human Development , New York University , New York , NY , USA
| | - Erinn E Kary
- a Department of Physical Therapy, Steinhardt School of Culture Education and Human Development , New York University , New York , NY , USA
| | - Daphna Harel
- b Center for the Promotion of Research Involving Innovative Statistical Methodology, Steinhardt School of Culture Education and Human Development , New York University , New York , NY , USA
| | - Bryan Hujsak
- c Vestibular Rehabilitation, The Ear Institute, Hearing and Balance Center , The New York Eye and Ear Infirmary of Mount Sinai , New York , NY , USA
| | - Ken Perlin
- d Computer Science Department, Courant Institute of Mathematical Sciences , New York University , New York , NY , USA
| |
Collapse
|
10
|
Abstract
Substantial advances in virtual reality technology open an exciting window toward better understanding of subdomains of balance control. Here, we studied whether a portable virtual reality headset can be used to test sensory integration for balance. Twenty young adults stood on a both-sides-up ball or floor. Moving spheres were projected from an Oculus Development Kit 2 at various amplitudes and frequencies. Participants' gains indicated visual "weighting" when standing on both-sides-up but not on the floor and "reweighting" with increased visual amplitude. Intraclass correlations showed acceptable to good reliability for all floor conditions and for some of the both-sides-up conditions when we repeated the protocol a week later. Future steps to further develop our paradigm into a clinical assessment of sensory integration for postural control are discussed.
Collapse
|
11
|
Lubetzky AV, McCoy SW, Price R, Kartin D. Response to Tendon Vibration Questions the Underlying Rationale of Proprioceptive Training. J Athl Train 2017; 52:97-107. [PMID: 28125270 DOI: 10.4085/1062-6050-52.1.06] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
CONTEXT Proprioceptive training on compliant surfaces is used to rehabilitate and prevent ankle sprains. The ability to improve proprioceptive function via such training has been questioned. Achilles tendon vibration is used in motor-control research as a form of proprioceptive stimulus. Using measures of postural steadiness with nonlinear measures to elucidate control mechanisms, tendon vibration can be applied to investigate the underlying rationale of proprioceptive training. OBJECTIVE To test whether the effect of vibration on young adults' postural control depended on the support surface. DESIGN Descriptive laboratory study. SETTING Research laboratory. PATIENTS OR OTHER PARTICIPANTS Thirty healthy adults and 10 adults with chronic ankle instability (CAI; age range = 18-40 years). INTERVENTION(S) With eyes open, participants stood in bilateral stance on a rigid plate (floor), memory foam, and a Both Sides Up (BOSU) ball covering a force platform. We applied bilateral Achilles tendon vibration for the middle 20 seconds in a series of 60-second trials and analyzed participants' responses from previbration to vibration (pre-vib) and from vibration to postvibration (vib-post). MAIN OUTCOME MEASURE(S) We calculated anterior-posterior excursion of the center of pressure and complexity index derived from the area under multiscale entropy curves. RESULTS The excursion response to vibration differed by surface, as indicated by a significant interaction of P < .001 for the healthy group at both time points and for the CAI group vib-post. Although both groups demonstrated increased excursion from pre-vib and from vib-post, a decrease was observed on the BOSU. The complexity response to vibration differed by surface for the healthy group (pre-vib, P < .001). The pattern for the CAI group was similar but not significant. Complexity changes vib-post were the same on all surfaces for both groups. CONCLUSIONS Participants reacted less to ankle vibration when standing on the BOSU as compared with the floor, suggesting that proprioceptive training may not be occurring. Different balance-training paradigms to target proprioception, including tendon vibration, should be explored.
Collapse
Affiliation(s)
- Anat Vilnai Lubetzky
- Department of Physical Therapy, Steinhardt School of Culture Education and Human Performance, New York University
| | | | - Robert Price
- Department of Rehabilitation Medicine, University of Washington, Seattle
| | - Deborah Kartin
- Department of Rehabilitation Medicine, University of Washington, Seattle
| |
Collapse
|
12
|
Crétual A. Which biomechanical models are currently used in standing posture analysis? Neurophysiol Clin 2015; 45:285-95. [PMID: 26388359 DOI: 10.1016/j.neucli.2015.07.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 07/23/2015] [Indexed: 12/22/2022] Open
Abstract
In 1995, David Winter concluded that postural analysis of upright stance was often restricted to studying the trajectory of the center of pressure (CoP). However, postural control means regulation of the center of mass (CoM) with respect to CoP. As CoM is only accessible by using a biomechanical model of the human body, the present article proposes to determine which models are actually used in postural analysis, twenty years after Winter's observation. To do so, a selection of 252 representative articles dealing with upright posture and published during the four last years has been checked. It appears that the CoP model largely remains the most common one (accounting for nearly two thirds of the selection). Other models, CoP/CoM and segmental models (with one, two or more segments) are much less used. The choice of the model does not appear to be guided by the population studied. Conversely, while some confusion remains between postural control and the associated concepts of stability or strategy, this choice is better justified for real methodological concerns when dealing with such high-level parameters. Finally, the computation of the CoM continues to be a limitation in achieving a more complete postural analysis. This unfortunately implies that the model is chosen for technological reasons in many cases (choice being a euphemism here). Some effort still has to be made so that bioengineering developments allow us to go beyond this limit.
Collapse
Affiliation(s)
- A Crétual
- M2S lab (Mouvement Sport Santé), University Rennes 2 - ENS Rennes - UEB, avenue Robert-Schuman, campus de Ker Lann, 35170 Bruz, France; MimeTIC team, INRIA Rennes, campus universitaire de Beaulieu, 35042 Rennes, France.
| |
Collapse
|
13
|
Lubetzky AV, Price R, Ciol MA, Kelly VE, McCoy SW. Relationship of multiscale entropy to task difficulty and sway velocity in healthy young adults. Somatosens Mot Res 2015; 32:211-8. [DOI: 10.3109/08990220.2015.1074565] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Anat V. Lubetzky
- Department of Physical Therapy, New York University, New York, NY, USA and
| | - Robert Price
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Marcia A. Ciol
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Valerie E. Kelly
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Sarah W. McCoy
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| |
Collapse
|
14
|
Time scale dependence of the center of pressure entropy: What characteristics of the neuromuscular postural control system influence stabilographic entropic half-life? Exp Brain Res 2015; 233:3507-15. [DOI: 10.1007/s00221-015-4420-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 08/14/2015] [Indexed: 10/23/2022]
|
15
|
Oliveira MRD, Inokuti TT, Bispo NNDC, Oliveira DADAP, Oliveira RFD, Silva Jr. RAD. Elderly individuals with increased risk of falls show postural balance impairment. FISIOTERAPIA EM MOVIMENTO 2015. [DOI: 10.1590/0103-5150.028.002.ao07] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Introduction Falls are a serious public health problem. Objective The aim of this study was to evaluate whether elderly individuals with increased risk of falls have a postural balance deficit, evaluated using a force platform during a one-leg stance. Materials and methods The sample consisted of 94 physically independent elderly individuals from the EELO project. The instruments used were the Downton scale, in order to assess the risk as well as the history of falls, and the force platform to measure postural balance through parameters from the center of pressure (COP). Results Elderly individuals were split into two groups according to the score observed with the Downton scale: G1 — low fall risk (score ≤ 2) — and G2 — high fall risk (score > 2). No differences were observed between the groups concerning gender (P > 0.05, Chi Square test). On the other hand, individuals from G2 showed postural instability when compared to individuals from G1, and individuals from G2 showed higher values in all COP parameters analysed (Mann-Whitney test, P < 0.05). Conclusion It can be concluded that the Downton scale has sensitivity for identifying individuals with balance impairment as well as a risk of falls. Therefore, it may be suggested that this scale may be useful in primary health care for detecting falls in the elderly.
Collapse
|