Trunk control impairment is responsible for postural instability during quiet sitting in individuals with cervical spinal cord injury

Milosevic, Matija; Masani, Kei; Kuipers, Meredith J.; Rahouni, Hossein; Verrier, Mary C.; McConville, Kristiina M. Valter; Popović, Miloš R.

doi:10.1016/j.clinbiomech.2015.03.002

Cited by 57 publications

(52 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Prior to training, we observed postural instability during seated balance that is consistent with previous reports in SCI [15, 20]. This case report demonstrates how overground robotic gait training with the Ekso engages the trunk muscles and could elicit training effects on static and dynamic seated balance control in people with high-thoracic motor-complete SCI.…”

Section: Discussionsupporting

confidence: 90%

Overground vs. treadmill-based robotic gait training to improve seated balance in people with motor-complete spinal cord injury: a case report

Chisholm

Alamro

Williams

et al. 2017

J NeuroEngineering Rehabil

View full text Add to dashboard Cite

BackgroundRobotic overground gait training devices, such as the Ekso, require users to actively participate in triggering steps through weight-shifting movements. It remains unknown how much the trunk muscles are activated during these movements, and if it is possible to transfer training effects to seated balance control. This study was conducted to compare the activity of postural control muscles of the trunk during overground (Ekso) vs. treadmill-based (Lokomat) robotic gait training, and evaluate changes in seated balance control in people with high-thoracic motor-complete spinal cord injury (SCI).MethodsThree individuals with motor-complete SCI from C7-T4, assumed to have no voluntary motor function below the chest, underwent robotic gait training. The participants were randomly assigned to Ekso-Lokomat-Ekso or Lokomat-Ekso-Lokomat for 10 sessions within each intervention phase for a total of 30 sessions. We evaluated static and dynamic balance control through analysis of center of pressure (COP) movements after each intervention phase. Surface electromyography was used to compare activity of the abdominal and erector spinae muscles during Ekso and Lokomat walking.ResultsWe observed improved postural stability after training with Ekso compared to Lokomat during static balance tasks, indicated by reduced COP root mean square distance and ellipse area. In addition, Ekso training increased total distance of COP movements during a dynamic balance task. The trunk muscles showed increased activation during Ekso overground walking compared to Lokomat walking.ConclusionsOur findings suggest that the Ekso actively recruits trunk muscles through postural control mechanisms, which may lead to improved balance during sitting. Developing effective training strategies to reactivate the trunk muscles is important to facilitate independence during seated balance activity in people with SCI.

show abstract

Section: Discussionsupporting

confidence: 90%

Overground vs. treadmill-based robotic gait training to improve seated balance in people with motor-complete spinal cord injury: a case report

Chisholm

Alamro

Williams

et al. 2017

J NeuroEngineering Rehabil

View full text Add to dashboard Cite

show abstract

“…Group sizes were equal in some studies, especially when paired comparisons were made, because balance is being imposed by design in this case (eg, 2 groups of size 14 each). However, in other studies, highly unbalanced scenarios were found (eg, 2 groups of sizes 6 and 10, respectively). Moreover, sometimes, comparisons of very small groups were reported (eg, pre‐post comparison for a group of three individuals; two unpaired groups with three and five individuals, respectively).…”

Section: Resultsmentioning

confidence: 77%

“…However, in other studies, highly unbalanced scenarios were found (eg, 2 groups of sizes 6 and 10, respectively 37 ). Moreover, sometimes, The authors did not mention the small sample size issue at all in 58 out of 167 studies (35%).…”

Section: Statistical Methods and Mentioning Potential Problemsmentioning

confidence: 78%

Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review

Zimmermann

Bolter

Sluka

et al. 2019

J Evidence Based Medicine

View full text Add to dashboard Cite

Aim Prevalence and incidence of spinal cord injury (SCI) are low. However, sample sizes have not been systematically examined yet, although this might represent useful information for study planning and power considerations. Therefore, our objective was to determine the median sample size in clinical trials on SCI individuals. Moreover, within small‐sample size studies, statistical methods and awareness of potential problems regarding small samples were examined. Methods We systematically reviewed all studies on human SCI individuals published between 2014 and 2015, where the effect of an intervention on one or more health‐related outcomes was assessed by means of a hypothesis test. If at least one group had a size <20, the study was classified as a small sample size study. PubMed was searched for eligible studies; subsequently, data on sample sizes and statistical methods were extracted and summarized descriptively. Results Out of 8897 studies 207 were included. Median total sample size was 18 (range 4‐582). Small sample sizes were found in 167/207 (81%) studies, resulting limitations and implications for statistical analyses were mentioned in 109/167 (65%) studies. Conclusions Although most recent SCI trials have been conducted with small samples, the consequences on statistical analysis methods and the validity of the results are rarely acknowledged.

show abstract

“…Neurological injuries, such as spinal cord injury (SCI) and traumatic brain injury, impact sitting balance. They often result in neuromuscular deficits that cause postural instability [ 5 ] and the inability to effectively compensate for external perturbations [ 6 – 9 ].…”

Section: Introductionmentioning

confidence: 99%

“…To date, no study has investigated how FES applied to the trunk muscles influences postural sway and trunk stiffness during quiet sitting. Postural control during quiet sitting [ 3 , 5 , 13 ] and standing [ 14 – 16 ], which can be evaluated using the center of pressure (COP) sway fluctuations, has been utilized to characterize the balance control of these two biomechanical systems. To understand the effects of trunk stability on the sitting balance control system, Reeves et al [ 3 ] investigated the COP fluctuations during quiet sitting on an unstable surface.…”

Section: Introductionmentioning

confidence: 99%

Trunk muscle co-activation using functional electrical stimulation modifies center of pressure fluctuations during quiet sitting by increasing trunk stiffness

Milosevic

Masani

et al. 2015

J NeuroEngineering Rehabil

Self Cite

View full text Add to dashboard Cite

BackgroundThe purpose of this study was to examine the impact of functional electrical stimulation (FES) induced co-activation of trunk muscles during quiet sitting. We hypothesized that FES applied to the trunk muscles will increase trunk stiffness. The objectives of this study were to: 1) compare the center of pressure (COP) fluctuations during unsupported and FES-assisted quiet sitting - an experimental study and; 2) investigate how FES influences sitting balance - an analytical (simulation) study.MethodsThe experimental study involved 15 able-bodied individuals who were seated on an instrumented chair. During the experiment, COP of the body projected on the seating surface was calculated to compare sitting stability of participants during unsupported and FES-assisted quiet sitting. The analytical (simulation) study examined dynamics of quiet sitting using an inverted pendulum model, representing the body, and a proportional-derivative (PD) controller, representing the central nervous system control. This model was used to analyze the relationship between increased trunk stiffness and COP fluctuations.ResultsIn the experimental study, the COP fluctuations showed that: i) the mean velocity, mean frequency and the power frequency were higher during FES-assisted sitting; ii) the frequency dispersion for anterior-posterior fluctuations was smaller during FES-assisted sitting; and iii) the mean distance, range and centroidal frequency did not change during FES-assisted sitting. The analytical (simulation) study showed that increased mechanical stiffness of the trunk had the same effect on COP fluctuations as the FES.ConclusionsThe results of this study suggest that FES applied to the key trunk muscles increases the speed of the COP fluctuations by increasing the trunk stiffness during quiet sitting.

show abstract

Trunk control impairment is responsible for postural instability during quiet sitting in individuals with cervical spinal cord injury

Cited by 57 publications

References 15 publications

Overground vs. treadmill-based robotic gait training to improve seated balance in people with motor-complete spinal cord injury: a case report

Overground vs. treadmill-based robotic gait training to improve seated balance in people with motor-complete spinal cord injury: a case report

Sample sizes and statistical methods in interventional studies on individuals with spinal cord injury: A systematic review

Trunk muscle co-activation using functional electrical stimulation modifies center of pressure fluctuations during quiet sitting by increasing trunk stiffness

Contact Info

Product

Resources

About