Brain network during balance in older adults: a functional near-infrared spectroscopy study / 中国康复理论与实践

ObjectiveTo study the brain network during balance control tasks in older adults. MethodsFrom January to April, 2022, 22 healthy young adults and 20 healthy older adults were recruited from the Fifth Affiliated Hospital of Guangzhou Medical University and communities. They were asked to finish standing tasks on the plantar pressure plate with eyes opening and closing, while the functional connectivities (FC) of prefrontal cortex (PFC) and primary motor cortex (PMC) were measured with functional near-infrared spectroscopy. ResultsCompared with the young adults, the area of the ellipse (Z = -2.884, P < 0.01) and the maximum swing (Z = -2.481, P < 0.05) increased in the older adults as eyes closing. During the standing task, the intra-FC of left (t = 2.978, P < 0.01) and right (Z = -3.123, P < 0.01) PFC decreased in the older adults, and the inter-FC of right PMC to left PFC (t = 2.087, P < 0.05) and right PFC to left PFC (t = 3.471, P < 0.001) decreased, too. ConclusionThe FC of PFC decreased in healthy older adults during balance control tasks, which may be a indicator for aging brain.

Effects of Bilateral Knee Osteoarthritis on Dynamic Balance Ability of Ankle Strategy in Aged Women / 医用生物力学

Objective To investigate the effect of bilateral knee osteoarthritis (KOA) ondynamic balance ability of ankle strategy in aged women. Methods The dynamic balance ability tester was used to test the balance score, the rotation speed, the maximum rotation speed, and the percentage of the target ball's residence time in each area of KOA patients (KOA group)and the general elderly (control group), and a comparative analysis between groups was conducted. Results The balance score of KOA group was lower than that of control group; the dynamic balance control ability of KOA group in the horizontal direction was basically the same as that of control group, but the dynamic balance control ability of KOA group in the vertical direction was weaker than that of control group.Bilateral KOA reduced dynamic balance ability of ankle strategy in the aged women.It could not affect the left-right symmetric balance ability of the aged women, but it would reduce its forward-backward symmetrical balance ability. Conclusions Bilateral KOA aged women may be more likely to fall forward or backward, while not easy to fall laterally. For elderly female patients with bilateral KOA, methods such as strengthening ankle joint strength, proprioception and responsiveness can be used to prevent falls that may be caused by reduced dynamic balance ability, especially falls in the forward and backward directions.

Extension Force Deficiency of the Lower Extremity in Squat Contributing to Increased Fall Risk in the Female Elderly / 中国运动医学杂志

Objectives To explore the relationship between the extension force deficiency of the lower extremity and fall risks among the senior female,so as to reveal the potential factors contributing to fall.Methods Forty community-dwelling senior females aged 65 and older were assigned to the group of fallers or non-fallers according to their reported fall history and measured fall risk index (FRI).Extension force of the lower extremity was measured through 3-consecutive fast squats on a force platform.The time for 3m-time up and going (TUG),as well as static and dynamic balance were also measured.Results Compared to the non-fallers,the fallers showed lower peak extension force per body weight (PEF/BW) of the left leg and larger asymmetry of the peak extension force per body weight between the two legs in squats.Correlation analysis showed that FRI had a strong negative relation with PEF/BW of the left leg and a strong positive relation with extension force asymmetry/body weight.Also time for 3m-TUG was positively related to all the force variables standardized by the body weight,especially for the left leg.However,the analysis failed to find a relationship between the velocity of the center of pressure (COP) sway on static balance and any force variables.In addition,PEF/BW of the left leg decreased and force asymmetry/body weight between the two legs increased with aging.Conclusion Extension force measurement in squat is an effective way to assess the muscle strength deficiency related to the increased fall risk.The extension force of the lower extremity to support the body weight in squat had a strong relation to the function decline in the dynamic balance,which contributes greatly to fall risk.The extensive force asymmetry in squat between the two legs is another important fall risk factor for the senior females.

Relationships between gait and standing balance in hemiplegia / 中华物理医学与康复杂志

Objective To study the relationships between the standing balance and walking ability of hemiplegic stroke survivors.Methods Eighty-eight post-stroke hemiplegic patients who could walk independently for more than 10 metres were selected into a patient group,while 88 healthy counterparts were recruited into a control group.Descriptors of the gait and balance function of both groups were collected using a gait and balance training and evahuation apparatus (Model:AL-600).The gait parameters were step width,walking speed,step length asymmetry (SLA),swing time asymmetry (SWTA) and stand time asymmetry (STA).The balance parameters studied were total trajectory length of the center of plantar pressure (COPD),the average left and right deviation of the center of plantar pressure (COPD-X) and the average anterio-posterior deviation of the center of plantar pressure (COPD-Y).Differences in indexes of gait and balance function between the two groups were analyzed using t-tests,and the relationships between the gait and balance indicators were analyzed using Pearson correlation coefficients.Results The walking speed,step width,COPD,COPD-X,COPD-Y,SLA,SWTA and STA of the patient group [(37.64± 18.29)cm/s,(14.45±4.17)cm,(66.75±29.04)cm,(2.04±1.41)cm,(2.48±1.28)cm,(1.30±0.46),(1.65±0.67) and (1.18±0.16),respectively] all increased significantly more compared to the control group [(90.76±14.72)cm/s,(8.70±2.62) cm,(27.84±6.54) cm,(1.30±0.53) cm,(1.68±0.40) cm,(1.07±0.06),(1.07±0.08) and (1.05±0.06),respectively],though the walking speed was significantly slower than that in the control group (P＜0.05).The patient group's average COPD-X showed slightly and moderately negative correlation with their walking speed,step width,SLA and SWTA (P＜0.05).COPD-Y was weakly related with step width (P＜0.05).Conclusion The standing balance of hemiplegic patients after stroke is related to their walking speed,step width and gait asymmetry.Especially significant correlation is observed between standing balance parameters such as COPD-X and gait parameters.

Effects of Sleep on Balance Control and Reaction Time to Visual Stimuli / 수면정신생리

OBJECTIVES: To find evidence that sleep is necessary for normal brain function, thus indicating that declines in both sleep quality and quantity are related to worse performance of many daily tasks and deteriorated physical functions. The present study investigates the relationships of balance control and reaction time with sleep quality. METHODS: 58 healthy (male 20, female 38) volunteers with informed consent participated in this study. The Self-reported Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality and relevant factors, and the subjects were divided into groups A (PSQI < 5) and B (PSQI ≥ 5) based on this index. Static balance control and reaction time to visual stimuli were conducted to assess their relationship with sleep quality. RESULTS: Group B exhibited excessive daytime sleepiness significantly more often compared to group A. Static balance control did not markedly change relative to sleep quality, but reaction time and error to visual stimuli were significantly increased in group B compared to group A. CONCLUSION: These findings indicate that a decline in sleep quality can result in delayed reactions, as well as decreased accuracy of these reactions. They also suggest that low sleep quality may be associated with changes in physical functions, including balance control through reduced selective attention.

Validation of the Japanese Version of the Balance Evaluation Systems Test (BESTest) / The Japanese Journal of Rehabilitation Medicine

Objective : The Balance Evaluation Systems Test (BESTest) is a new balance assessment set based on systems theory. The purpose was to examine the validity of the Japanese version of the BESTest (J-BESTest) that we translated. Methods : The J-BESTest was produced using a translation and back translation method referenced from a guideline proposed by Guillemin et al. We tested 20 patients with balance dysfunction due to various diseases and 5 healthy persons with the J-BESTest, the Berg Balance Scale (BBS), the Falls Efficacy Scale-International (FES-I) and the Activities-specific Balance Confidence Scale (ABC Scale). We assessed the concurrent validity of the J-BESTest by comparing it with the other measures using Spearman's correlation method. Furthermore, we compared the ability of the J-BESTest to discriminate balance dysfunction with that of the BBS using receiver operating characteristic (ROC) analyses. Results : The J-BESTest was highly correlated with BBS (<i>r</i>=0.84, <i>p</i><0.01), FES-I (<i>r</i>=-0.61, <i>p</i><0.01) and ABC Scale (<i>r</i>=0.63, <i>p</i><0.01). The distribution of the BBS score was more skewed compared with the J-BESTest and had a ceiling effect (6 participants had perfect scores with BBS versus none with the J-BESTest). The area under the ROC curve (AUC) of the J-BESTest was significantly larger than that of BBS (BBS 0.75, 95% confidence interval 0.56-0.94 versus J-BESTest 0.94, 95% confidence interval 0.84.1.0, <i>p</i><0.05). Conclusion : The J-BESTest was suggested as a clinically useful tool, with good concurrent validity and better sensitivity and specificity than BBS, to identify people with mild balance dysfunction.

Validation of the Japanese Version of the Mini-Balance Evaluation Systems Test (Mini-BESTest) / The Japanese Journal of Rehabilitation Medicine

Objective : The Mini-Balance Evaluation Systems Test (Mini-BESTest) is an assessment tool for dynamic balance dysfunction developed by simplifying the Balance Evaluation Systems Test (BESTest). The purpose of our study was to examine the validity of the Japanese version of the Mini-BESTest (J-Mini-BESTest) we translated. Methods : The J-Mini-BESTest was produced using a translation and back translation method referring to a guideline proposed by Guillemin et al. We tested 20 patients with balance dysfunction due to various diseases and 7 healthy persons with the J-Mini-BESTest, the Berg Balance Scale (BBS), the Falls Efficacy Scale-International (FES-I) and the Activities-specific Balance Confidence Scale (ABC Scale). We assessed the concurrent validity of the J-Mini-BESTest by comparing it with the other measures using the Spearman's correlation method. Results : The average assessment time when using the J-Mini-BESTest was 20.0 minutes. The J-Mini-BESTest was correlated with the BBS (<i>r</i>=0.82, <i>p</i><0.01), FES-I (<i>r</i>=-0.72, <i>p</i><0.01) and ABC Scale (<i>r</i>=0.80, <i>p</i><0.01). The distribution of the BBS scores was more skewed compared to the J-Mini-BESTest (BBS skewness=-1.30 vs. J-Mini-BESTest skewness=-0.47) and the BBS also had a ceiling effect (9 participants had a perfect score in the BBS versus none in the J-Mini-BESTest). Conclusion : The J-Mini-BESTest was suggested as a clinically useful tool for detecting subtle dynamic balance deficits with good concurrent validity.

Balance Control and Knee Osteoarthritis Severity

OBJECTIVE: To investigate balance control according to the severity of knee osteoarthritis (OA) using clinical tests and Tetra-ataxiometric posturography (Tetrax(R)). METHOD: A total 80 patients with primary knee OA classified according to American College of Rheumatology criteria, and 40 age-matched controls were enrolled in this study. Of those with OA, 39 patients had mild OA (Kellgren-Lawrence [KL] grade 1, 2) and the other 41 had moderate to severe OA (KL grade 3, 4). The postural control capabilities of the subjects were assessed using the timed up and go test (TUG), Berg balance scale (BBS), and Tetrax(R), which utilizes two paired force plates to measure vertical pressure fluctuations over both heels and forefeet. The subjects were checked for their stability index (ST), Fourier index, weight distribution index (WDI), and synchronization index (SI) in eight positions using Tetrax(R). RESULTS: Patients with moderate to severe OA exhibited significantly higher stability indices in all positions than patients with mild OA. The Fourier index was also higher in patients with moderate to severe OA than in patients with mild OA. However, the weight distribution index and synchronization of both heels and forefeet were not significantly different in the three groups. CONCLUSION: These findings suggest that patients with moderate to severe OA have more deficits in balance control than those with mild disease. Therefore, evaluation of balance control and education aimed at preventing falls would be useful to patients with knee OA.

Effects of the Balance Control of the Affected Lower Extremityon Balance and Gait in Hemiparetic Patients

OBJECTIVE: To investigate the effects of balance control of affected lower extremity on berg balance scale and gait in hemiparetic patients, using the newly developed balance control trainer of lower extremity. METHOD: Thirty five hemiparetic patients who could stand and ambulate more than 10 meters without assist on even surface were included in this study. The balance control trainer of lower extremity was designed to measure weight shift and knee flexion angle of hemiparetic side and to play a game named "Board cleaner" which use these data, so considering the vertical movement of the center of gravity. We measured above three parameters, and also evaluated with clinical tests including berg balance scale (BBS). We evaluated correlations between parameters on the balance control trainer of lower extremity and clinical parameters. RESULTS: Weight shifting to affected side statistically significantly correlated only with BBS. Affected knee flexion had statistically significant correlations with all clinical tests examined, especially 10 meters walking time (10mWT), timed up and go test (TUG), and BBS. Scores earned from board cleaner game also had statistically significant correlations with all clinical tests examined, especially 10mWT, TUG, and BBS. CONCLUSION: Correlation exists between the ability to control the affected knee measured by balance control trainer of lower extremity and clinical parameters including 10mWT, TUG, and BBS, so we think the balance control trainer can be a useful tool for the evaluation in hemiparetic patients.

The feasibility of segmental method in testing human balance control with a three dimensional motion analysis system / 中华物理医学与康复杂志

Objective To investigate the reliability and sensitivity of a three dimensional motion analysis system by using the segmental method.Methods Ten healthy young men participated in this study.They were asked to stand with one leg and with their eyes open and closed,respectively,each lasted for 30 seconds and was re- peated twice.According to the 12-segment rigid body model of the human body,twenty-one infrared light emitting di- ode(1RED)markers were placed over the bony prominences on the proximal and distal ends of each segment,the motion track of the IRED markers was recorded by the three dimensional motion analysis system.The mean sway am- plitude( MSA )and the sway path(SP)of the center of gravity(COG)were calculated.Correlation analysis was used to determine the reliability between the two repetitions.Paired sample t-test was used to determine the sensitivity be- tween the eyes open and closed conditions.Results The correlation coefficients of the MSA of the COG in the eyes open and closed conditions were 0.623 and 0.018,respectively,and the correlation coefficients of the SP of the COG were 0.936 and 0.654,respectively.It was also shown that significant differences existed among the three directions of the MSA of the COG and the SP of the COG.Conclusion Besides the weak reliability of the MSA of COG in the eyes closed condition,the high reliability and sensitivity of the MSA and SP of the COG are found.The segmental method can be used in the scientific study of human balance control.

Development of constant-temperature-and-humidity test box used in medicament stability experiment / 医疗卫生装备

This article introduces a constant-temperature-and-humidity test box, which, with a high-performance Aduc812 singlechip as the core, is composed of an integrated temperature and humidity sensor, a serial keyboard controller and a lattice-style liquid crystal module. With balance control mode of temperature an d humidity, PID control, temperature and humidity decoupling applied, the high-r esponse-speed and high-precision control can be fulfilled.