Dynamic balance control during sit-to-stand movement: An examination with the center of mass acceleration

2012 ◽  
Vol 45 (3) ◽  
pp. 543-548 ◽  
Author(s):  
Masahiro Fujimoto ◽  
Li-Shan Chou
Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4193 ◽  
Author(s):  
Cunguang Lou ◽  
Chenyao Pang ◽  
Congrui Jing ◽  
Shuo Wang ◽  
Xufeng He ◽  
...  

The center of plantar pressure (COP) reflects the dynamic balance of subjects to a certain extent. In this study, wearable pressure insoles are designed, body pose measure is detected by the Kinect sensor, and a balance evaluation system is formulated. With the designed games for the interactive actions, the Kinect sensor reads the skeletal poses to judge whether the desired action is performed, and the pressure insoles simultaneously collect the plantar pressure data. The COP displacement and its speed are calculated to determine the body sway and the ability of balance control. Significant differences in the dispersion of the COP distribution of the 12 subjects have been obtained, indicating different balancing abilities of the examined subjects. A novel assessment process is also proposed in the paper, in which a correlation analysis is made between the de facto sit-to-stand (STS) test and the proposed method; the Pearson and Spearman correlations are also conducted, which reveal a significant positive correlation. Finally, four undergraduate volunteers with a right leg sports injury participate in the experiments. The experimental results show that the normal side and abnormal side have significantly different characters, suggesting that our method is effective and robust for balance measurements.


2020 ◽  
Vol 8 (4_suppl3) ◽  
pp. 2325967120S0015
Author(s):  
Tracy Zaslow ◽  
Camille Burton ◽  
Nicole M. Mueske ◽  
Adriana Conrad-Forrest ◽  
Bianca Edison ◽  
...  

Background: Previous research has identified deficient dual-task balance control at the time of return to play (RTP) and possible worsening after RTP in older adolescents/young adults with concussion. These findings have not been investigated in younger patients with concussion. Hypothesis/Purpose: We hypothesized that concussed adolescents would have slower walking speed and increased medial-lateral (ML) center of mass (COM) movement, which would normalize by the time of RTP but worsen after resuming activity. Methods: 13 adolescent concussion patients (7 male; age 10-17 years) were prospectively evaluated at their initial visit (IV) (mean 18, range 4-43 days post-concussion), at RTP clearance (mean 46, range 12-173 days post-concussion), and one month later (mean 26, range 20-41 days post-RTP) along with 11 controls (3 male) seen for similarly timed visits. Standing balance was assessed using range and root mean squared (RMS) COM motion in the anterior-posterior (AP) and ML directions during standing on both legs with eyes open while performing quiet standing, dual-task audio Stroop, side-to-side head turns, and side-to-side thumb tracking tasks. Dynamic balance was assessed using walking speed and COM ML range and velocity during walking alone and with side-to-side head turns and verbal fluency (reciting words starting with “F”) dual tasks. Patients were compared against controls using t-tests, and changes over time were evaluated using linear mixed-effects regression. Results: During standing, patients had higher COM ML RMS than controls at IV during head turns and higher COM AP range during thumb tracking. COM ML motion decreased from IV to RTP (head turns range -6.5mm, p=0.058; head turns RMS -16.8mm, p=0.002; thumb range 9.2mm, p=0.012) and increased from RTP to 1 month follow-up (head turns RMS +10.0mm, p=0.040; Stroop RMS +8.4mm, p=0.086). Patients walked slower than controls at IV during all tasks, and COM ML range was higher in patients vs. controls during verbal fluency at IV and RTP. Walking speed increased from IV to RTP during verbal fluency (+7.8cm/s, p=0.044), from RTP to post-RTP in single task walking (+6.1cm/s, p=0.041), and at each successive visit during head turns (+6.0cm/s and +6.5cm/s, p<0.07). COM ML range also decreased in patients from IV to RTP with verbal fluency (-14.7mm, p=0.011) and from RTP to post-RTP in single task walking ( 4.0mm, p=0.061). Conclusion: Adolescent concussion patients had deficits in static and dynamic balance control at initial presentation. This tended to improve by RTP and only worsened post-RTP for dual-task ML control during standing, suggesting that current conservative treatment protocols are appropriate.


Author(s):  
Tiziana Lencioni ◽  
Denise Anastasi ◽  
Ilaria Carpinella ◽  
Anna Castagna ◽  
Alessandro Crippa ◽  
...  

Maintaining a stable gait requires a dynamic balance control, that can be altered in persons with Multiple Sclerosis (MS), Stroke (ST), and Parkinson’s disease (PD). The understanding of the strategy for Center of Mass (CoM) positioning adopted by patients during walking is important to be able to program treatments aimed at improving gait control and preventing falls. Forty-four persons with a mild-to-moderate neurological disorder (20 with MS, 14 with ST, 10 with PD) underwent clinical examination and gait analysis. Ten Healthy Subjects (HS) walking at matched speed provided the normative data. Dynamic balance was assessed using the margin of stability (MoS). It was calculated as the distance between the extrapolated Center of Pressure and the extrapolated CoM at mid-stance. The MoS values for lower limbs were calculated in patients and compared with speed-matched values of HS. Persons with neurological disorder showed increased MoS in the medio-lateral direction with respect to HS. Within-group comparison analysis showed a symmetry between lower limbs in HS (Mean (95%CI) [mm], dominant vs non-dominant limb, 43.3 (31.9–54.6) vs 42.9 (28.8–56.9)) and PD (less affected vs more affected limb, 71.1 (59.8–82.5) vs 72.5 (58.5–86.6)), while a significant asymmetry was found in MS (54.4 (46.4–62.4) vs 81.1 (71.2–91.1)) and ST (52.1 (42.6–61.7) vs 74.7 (62.8–86.6)) participants. The history of falls was comparable among PD, MS, and ST groups, and the MoS in the frontal plane showed a strong correlation with these records. Objective assessment of MoS revealed pathology-specific strategies showing different impacts in MS, ST, and PD on the ability to control CoM information to manage the balance between limbs during gait. MoS evaluation will provide useful information to address a tailored rehabilitation program and to monitor disease progression.


Motor Control ◽  
2020 ◽  
Vol 24 (1) ◽  
pp. 150-167
Author(s):  
Yuko Kuramatsu ◽  
Yuji Yamamoto ◽  
Shin-Ichi Izumi

This study investigated the sensorimotor strategies for dynamic balance control in individuals with stroke by restricting sensory input that might influence task accomplishment. Sit-to-stand movements were performed with restricted vision by participants with hemiparesis and healthy controls. The authors evaluated the variability in the position of participants’ center of mass and velocity, and the center-of-pressure position, in each orthogonal direction at the lift-off point. When vision was restricted, the variability in the mediolateral center-of-pressure position decreased significantly in individuals with hemiparesis, but not in healthy controls. Participants with hemiparesis adopted strategies that explicitly differed from those used by healthy individuals. Variability may be decreased in the direction that most requires accuracy. Individuals with hemiparesis have been reported to have asymmetrical balance deficits, and that meant they had to prioritize mediolateral motion control to prevent falling. This study suggests that individuals with hemiparesis adopt strategies appropriate to their characteristics.


2021 ◽  
pp. 1-14
Author(s):  
Bauke Wybren Dijkstra ◽  
Moran Gilat ◽  
L. Eduardo Cofré Lizama ◽  
Martina Mancini ◽  
Bruno Bergmans ◽  
...  

Background: People with Parkinson’s disease and freezing of gait (FOG; freezers) suffer from pronounced postural instability. However, the relationship between these phenomena remains unclear and has mostly been tested in paradigms requiring step generation. Objective: To determine if freezing-related dynamic balance deficits are present during a task without stepping and determine the influence of dopaminergic medication on dynamic balance control. Methods: Twenty-two freezers, 16 non-freezers, and 20 healthy age-matched controls performed mediolateral weight-shifts at increasing frequencies when following a visual target projected on a screen (MELBA task). The amplitude and phase shift differences between center of mass and target motion were measured. Balance scores (Mini-BESTest), 360° turning speed and the freezing ratio were also measured. Subjects with Parkinson’s disease were tested ON and partial OFF (overnight withdrawal) dopaminergic medication. Results: Freezers had comparable turning speed and balance scores to non-freezers and took more levodopa. Freezers produced hypokinetic weight-shift amplitudes throughout the MELBA task compared to non-freezers (p = 0.002), which were already present at task onset (p < 0.001). Freezers also displayed an earlier weight-shift breakdown than controls when OFF-medication (p = 0.008). Medication improved mediolateral weight-shifting in freezers and non-freezers. Freezers decreased their freezing ratio in response to medication. Conclusion: Hypokinetic weight-shifting proved a marked postural control deficit in freezers, while balance scores and turning speed were similar to non-freezers. Both weight-shift amplitudes and the freezing ratio were responsive to medication in freezers, suggesting axial motor vigor is levodopa-responsive. Future work needs to test whether weight-shifting and freezing severity can be further ameliorated through training.


2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Rajal G Cohen ◽  
Jason L Baer ◽  
Ramyaa Ravichandra ◽  
Daniel Kral ◽  
Craig McGowan ◽  
...  

Abstract Background and Objectives Increased fall risk in older adults is associated with declining balance. Previous work showed that brief postural instructions can affect balance control in older adults with Parkinson’s disease. Here, we assessed the effects of brief instructions on static and dynamic balance in healthy older adults. Research Design and Methods Nineteen participants practiced three sets of instructions, then attempted to implement each instructional set during: (1) quiet standing on foam for 30 s with eyes open; (2) a 3-s foot lift. “Light” instructions relied on principles of reducing excess tension while encouraging length. “Effortful” instructions relied on popular concepts of effortful posture correction. “Relax” instructions encouraged minimization of effort. We measured kinematics and muscle activity. Results During quiet stance, Effortful instructions increased mediolateral jerk and path length. In the foot lift task, Light instructions led to the longest foot-in-air duration and the smallest anteroposterior variability of the center of mass, Relax instructions led to the farthest forward head position, and Effortful instructions led to the highest activity in torso muscles. Discussion and Implications Thinking of upright posture as effortless may reduce excessive co-contractions and improve static and dynamic balance, while thinking of upright posture as inherently effortful may make balance worse. This may partly account for the benefits of embodied mindfulness practices such as tai chi and Alexander technique for balance in older adults. Pending larger-scale replication, this discovery may enable physiotherapists and teachers of dance, exercise, and martial arts to improve balance and reduce fall risk in their older students and clients simply by modifying how they talk about posture.


2016 ◽  
Vol 28 (02) ◽  
pp. 1650011
Author(s):  
Shaun C. Resseguie ◽  
Li Jin ◽  
Michael E. Hahn

Powered prosthetic feet (PPF) are designed to provide transtibial amputees (TTA) with active propulsion and range of motion similar to that of the biological limb. Previous studies have demonstrated the PPF’s ability to increase TTA walking speeds while reducing the energetic costs, however, little is known about its effects on dynamic balance control. The purpose of this pilot study was to assess dynamic balance control in TTA subjects during level ground walking and obstacle-crossing tasks. Control subjects ([Formula: see text]) and TTA subjects ([Formula: see text]) were instructed to complete a series of functional walking tasks. The TTA subjects completed the walking protocol twice, first in their passive energy-storing prosthetic foot (ESPF) and again in the prescribed PPF after two weeks of acclimation. Motion data were collected via a 10-camera system with a 53-marker and 15-segment body model. Whole body medial-lateral center of mass motion (displacement and peak velocity) was analyzed and used as a functional indicator of dynamic balance control. Findings indicate no difference in the dynamic balance control of TTA wearing the PPF compared to the ESPF. However, there was an observed trend of walking speed and obstacle height affecting balance control within the groups.


2014 ◽  
Vol 945-949 ◽  
pp. 777-780
Author(s):  
Tao Liu ◽  
Yong Xu ◽  
Bo Yuan Mao

Firstly, according to the structure characteristics of precision centrifuge, the mathematical model of its dynamic balancing system was set up, and the dynamic balancing scheme of double test surfaces, double emendation surfaces were established. Then the dynamic balance system controller of precision centrifuge was designed. Simulation results show that the controller designed can completely meet the requirements of precision centrifuge dynamic balance control system.


Sign in / Sign up

Export Citation Format

Share Document