
Contributions
Abstract: P1317
Type: Poster
Abstract Category: RIMS - Multi-disciplinary rehabilitation
Impaired balance is one of the most common and disabling multiple sclerosis (MS) symptoms. Anticipatory (APAs) and compensatory (CPAs) postural adjustments are two main postural mechanisms to maintain and restore balance during expected and unexpected perturbations. The main purpose of this study was an update to previous literatures and to investigate the relationship between APAs and CPAs and falls in MS subjects. Seventeen MS fallers, 11 MS non-fallers and 11 age-and-gender matched healthy controls were exposed to backward external pull perturbations. Subjects received pull perturbations through a cable attached to an axillary belt. The perturbations were either predictable or unpredictable as subjects were informed through verbal auditory feedback. Electrical activity of 12 leg and trunk muscles were recorded and quantified within the time intervals typical of APAs and CPAs. The results revealed that MS subjects with previous fall history had significant delay in the both anticipatory and compensatory onsets of muscle activity (p< 0.0.5 for bilateral erector spinae, Left biceps femoris and left rectus femoris muscles) in comparison to non-faller and healthy control subjects. In addition, MS subjects with previous fall history exhibited smaller activity levels in the most studied muscles in the both anticipatory and compensatory phase of perturbations. The results revealed apparent deficits in the APAs during expected perturbations in MS subjects with a previous fall history. The reduced APAs were not accompanied by greater and earlier compensatory muscle activity. This inability to maintain and restore balance in response to external perturbations may explain high incidence of falls in these individuals. Future rehabilitation programs should focus on perturbation training protocols in order to improve both anticipatory and compensatory responses to daily perturbations.
Disclosure: "Shirin Tajali: nothing to disclose"
Abstract: P1317
Type: Poster
Abstract Category: RIMS - Multi-disciplinary rehabilitation
Impaired balance is one of the most common and disabling multiple sclerosis (MS) symptoms. Anticipatory (APAs) and compensatory (CPAs) postural adjustments are two main postural mechanisms to maintain and restore balance during expected and unexpected perturbations. The main purpose of this study was an update to previous literatures and to investigate the relationship between APAs and CPAs and falls in MS subjects. Seventeen MS fallers, 11 MS non-fallers and 11 age-and-gender matched healthy controls were exposed to backward external pull perturbations. Subjects received pull perturbations through a cable attached to an axillary belt. The perturbations were either predictable or unpredictable as subjects were informed through verbal auditory feedback. Electrical activity of 12 leg and trunk muscles were recorded and quantified within the time intervals typical of APAs and CPAs. The results revealed that MS subjects with previous fall history had significant delay in the both anticipatory and compensatory onsets of muscle activity (p< 0.0.5 for bilateral erector spinae, Left biceps femoris and left rectus femoris muscles) in comparison to non-faller and healthy control subjects. In addition, MS subjects with previous fall history exhibited smaller activity levels in the most studied muscles in the both anticipatory and compensatory phase of perturbations. The results revealed apparent deficits in the APAs during expected perturbations in MS subjects with a previous fall history. The reduced APAs were not accompanied by greater and earlier compensatory muscle activity. This inability to maintain and restore balance in response to external perturbations may explain high incidence of falls in these individuals. Future rehabilitation programs should focus on perturbation training protocols in order to improve both anticipatory and compensatory responses to daily perturbations.
Disclosure: "Shirin Tajali: nothing to disclose"