A comparison of electronystagmography results with posturography findings from the BalanceTrak 500

Efficacy of CDP and ENG in Detecting Balance Impairment Associated With Cerebral White Matter Changes

OBJECTIVE

To examine the relationship between white matter changes (WMCs) and abnormal balance test results on computerized dynamic posturography (CDP) and electronystagmography (ENG). Also, to compare the utility of CDP with ENG for this purpose.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary care referral center.

PATIENTS

A retrospective review of 137 subjects was conducted. The CDP and ENG results were compared between patients with (80) and without (57) WMCs as detected byT2/fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI).

MAIN OUTCOME MEASURES

CDP analysis consisted of both sensory organization test (SOT) and motor control test (MCT) results, and ENG analysis included positional, oculomotor, and bithermal caloric testing. Multivariate logistic regression was performed to control for age and hearing loss discrepancies between the two groups.

RESULTS

Ninety three percent of patients with WMCs had an abnormal CDP result, as compared with 44% of patients lacking WMCs (p < 0.001). Eighty six percent of patients with WMCs had an abnormal ENG, as did 81% of patients without WMCs (p = 0.435). Multivariate regression analysis maintained that an abnormal CDP result was significantly associated with WMCs when controlling for age and hearing loss (p < 0.001).

CONCLUSION

These findings suggest that patients with cerebral small-vessel ischemic changes are significantly more likely to have an abnormal balance result as detected by CDP, than by ENG. Hence, CDP may be a better study to identify and document patients who have balance dysfunction associated with this central finding. Such identification will permit additional evaluation and treatment based on objective confirmation of balance dysfunction, in this group of balance-impaired subjects who may have normal ENG's.

Between-subjects differences of within-subject variability in repeated balance measures: consequences on the minimum detectable change

When repeating tests on a subject it is important to know if changes of the results are significant. Researchers have used measures of reliability, e.g., intraclass correlation coefficient (ICC) and minimum detectable change (MDC), to assess reliability and validity of balance measures and equipment, and to determine what constitutes a significant change (SC). Using ICC and MDC assumes measurement differences are random in nature, i.e., that within-subject variability is similar between subjects. We investigated if this assumption holds true for center of pressure based balance measures. 20 repetitions of the tests comprising the modified Clinical Test of Sensory Integration in Balance (mCTSIB) protocol were performed by two 17-subject groups simulating laboratory and clinical conditions. Force platform based computerized dynamic posturography Vestibular Technologies CAPS(®) systems exceeding ISPGR recommended accuracy, precision and resolution were used to perform the testing and collect the data. The MDC was compared with the SC computed from individual subjects' within-subject standard deviation, with and without averaging 3 repetitions. We found within-subjects variability was not similar between subjects, rendering the applicability of ICC and MDC questionable. The MDC greatly underestimated the SC for some subjects and overestimated it for others, therefore it should be used with extreme caution, if at all. It seems that for balance measures the SC is more a subject's rather than an instrument's or test's characteristic and should be evaluated on an individual basis. We suggest doing so might provide useful additional clinical information about a subject.

Fall risk profile and quality-of-life status of older chiropractic patients

OBJECTIVES

The primary aim of this study was to estimate the prevalence of fall risk factors in older chiropractic patients. The secondary aim was to investigate the quality-of-life status of older chiropractic patients and to see whether a history of falling was related to quality-of-life status.

METHODS

A cross-sectional study was conducted at 12 chiropractic practices throughout Auckland, New Zealand, and Melbourne, Australia. The study involved gaining a profile of health status, fall history, and fall risk from active chiropractic patients who were 65 years or older.

RESULTS

One hundred ten older chiropractic patients were approached, and 101 agreed to participate in this study (response rate, 91.8%). Thirty-five percent of participants had experienced at least 1 fall in the previous 12 months. Of those that had fallen, 80% had at least a minor injury, with 37% of fallers requiring medical attention and 6% suffering a serious injury. The prevalence of most fall risk factors was consistent with published data for community-dwelling older adults. Quality of life of older chiropractic patients appeared to be good, but fallers reported a lower physical component summary score compared with nonfallers (P = .04).

CONCLUSIONS

A portion of the older chiropractic patients sampled in this study had a substantial risk of falling. This risk could be assessed on a regular basis for the presence of modifiable fall risk factors, and appropriate advice, given when fall risks are identified.

Comparison of balance assessment modalities in emergency department elders: a pilot cross-sectional observational study

Background

More than one-third of US adults 65 and over fall every year. These falls may cause serious injury including substantial long-term morbidity (due declines in activities of daily living) and death. The emergency department (ED) visit represents an opportunity for identifying high risk elders and potentially instituting falls-related interventions. The unique characteristic of the ED environment and patient population necessitate that risk-assessment modalities be validated in this specific setting. In order to better identify elders at risk of falls, we examined the relationship between patient-provided history of falling and two testing modalities (a balance plate system and the timed up-and-go [TUG] test) in elder emergency department (ED) patients.

Methods

We conducted a cross-sectional observational study of patients ≥ 60 years old being discharged from the ED. Patient history of falls in the past week, month, 6 months, and year was obtained. Balance plate center of pressure excursion (COP) measurements and TUG testing times were recorded. COP was recorded under four conditions: normal stability eyes open (NSEO) and closed (NSEC), and perturbed stability eyes open and closed. Correlation between TUG and COP scores was measured. Univariate logistic regression was used to identify the relationship between patient-provided falls history and the two testing modalities. Proportions, likelihood ratios, and receiver-operating-characteristic (ROC) curves for prediction of previous falls were reported.

Results

Fifty-three subjects were enrolled, 11% had fallen in the previous week and 42% in the previous year. There was no correlation between TUG and any balance plate measurements. In logistic regression, neither testing modality was associated with prior history of falls (p > 0.05 for all time periods). Balance plate NSEO and NSEC testing cutoffs could be identified which were 83% sensitive and had a negative likelihood ratio (LR-) of 0.3 for falls in the past week. TUG testing was not useful for falls in the past week, but performed best for more distant falls in the past month, 6 months, or year. TUG cutoffs with sensitivity over 80% and LR(-) of 0.17-0.32 could be identified for these time periods.

Conclusion

Over 40% of community-dwelling elder ED patients report a fall within the past year. Balance plate and TUG testing were feasibly conducted in an ED setting. There is no relationship between scores on balance plate and TUG testing in these patients. In regression analysis, neither modality was significantly associated with patient provided history of falls. These modalities should not be adopted for screening purposes in elders in the ED setting without validation in future studies or as part of multi-factorial risk assessment.

Test order effects of computerized dynamic posturography and calorics

PURPOSE

To determine whether there is a test order effect of the caloric subtest of videonystagmography on the Sensory Organization Test (SOT) of computerized dynamic posturography, and to assess the learning effect of multiple posturography test sessions on the SOT score.

METHOD

Scores on the 6 SOT conditions before and after caloric testing were compared for 10 participants age 18-36 years. Four SOT sessions were completed prior to caloric testing to assess the presence of a learning effect and establish precaloric baseline SOT scores. All participants had normal vestibular systems with no history of dizziness or imbalance.

RESULTS

Caloric testing had a significant effect on the equilibrium score for only 1 of 6 test conditions. While meeting statistical significance, the actual change in score for this condition was very small. Equilibrium scores improved for the more difficult test conditions between the 1st and 2nd SOT sessions.

CONCLUSION

Results indicate that there are minimal test order effects of calorics on the SOT. Results confirm that a significant improvement in score for more challenging test conditions occurs between SOT Sessions 1 and 2 as a result of learning. Therefore, clinicians must be cautious when using posturography to monitor patient improvement.

Comparison of electronystagmography results with dynamic posturography findings in patients with vestibular schwannoma

CONCLUSION

Condition-5-score (C5S) and condition-6-score (C6S) of computerized dynamic platform posturography (CDPP) can detect the presence of a functional deficit of the lateral semicircular canal (and the superior vestibular nerve), irrespective of the central vestibular compensatory status, in vestibular schwannoma (VS) patients.

OBJECTIVES

To test whether CDPP findings differ between VS patients with and without asymmetry on caloric and/or rotational ENG studies.

PATIENTS AND METHODS

This was a retrospective review of 216 consecutive patients with VS. C5S and C6S of CDPP (Equitest) were compared among patients with normal caloric and rotational studies, patients with asymmetry on caloric studies and normal rotational studies, and patients with asymmetric caloric and rotational studies using the Wilcoxon-Mann-Whitney test.

RESULTS

C5S and C6S of VS patients with normal caloric and rotational studies were significantly higher than in VS patients with either asymmetry on both rotational and caloric test results (p<0.001 for both C5S and C6S) or normal rotational studies and asymmetry on caloric testing (p<0.001 for both C5S and C6S). Neither C5S nor C6S were significantly different between patients with asymmetry on caloric testing and normal rotational studies and patients with asymmetry on both rotational and caloric testing.

Posturographic Changes Associated with Music Listening

OBJECTIVES

The aim of this study was to ascertain whether listening to music might cause changes in human stability and be useful in fall prevention and rehabilitation. The aim was also to find what percentage of subjects without neurologic signs or symptoms associated with falling had less than ideal stability.

DESIGN

Computer dynamic posturography (CDP) provided stability scores in 266 subjects without a history of falls or vertigo. Subjects were randomized into several different music listening groups and one control group. The music listening groups were given a daily specific music listening task and CDP was obtained 10 minutes, 1 week, and 1 month after the subject's treatment in a blinded fashion.

RESULTS

Tests of postural stability have shown that 73% of 266 subjects without neurologic signs or symptoms were found to have balance abnormalities associated with an increased probability of falling. We have demonstrated positive changes in stability scores in these subjects who underwent a variety of music listening tasks, with the music of Nolwenn Leroy found to be significantly superior to other music tested.

CONCLUSIONS

Listening to certain types of music has the potential to change human stability and promote change in the field of fall prevention and rehabilitation with a potential to decrease disability.

Posturographic testing and motor learning predictability in gymnasts

PURPOSE

One aim of this study was to find if there was a difference between balance and stability between elite level gymnasts and non-gymnasts. Another aim was to find if there was a relationship between dynamic posturographic scores associated with sway fatigue or adaptability and the ability to learn new gymnastic routines. The ultimate aim of the study was to improve gymnastic performance while reducing the probability of injury.

METHODS

Computer dynamic posturography (CDP) provided stability scores, fatigability ratios and adaptation ratios in elite level gymnasts and non-gymnasts controls. Relationships between the postural integrity of gymnasts and non-gymnasts were calculated. The gymnasts were trained in a novel gymnastic routine and performance outcomes were compared to the CDP outcomes.

RESULTS

Tests of postural stability have shown that gymnasts have greater postural stability than non-gymnasts. Gymnasts whose adaptability scores were higher were able to learn and perform new motor routines better than those with lower adaptability scores or high fatigability ratios.

CONCLUSIONS

While gymnasts have greater postural integrity than do non-gymnasts, CDP can identify individuals whose ability to perform new motor activities might be impaired. Methodology to improve functional stability not associated with the motor task may contribute to increased sports performance and decreased probability of injury.

Does patient-perceived handicap correspond to the modified clinical test for the sensory interaction on balance?

OBJECTIVE

To determine whether patient self-reported handicap correlates with scores obtained from the modified Clinical Test for the Sensory Interaction on Balance as assessed by the Neurocom VSR Balance Master platform.

STUDY DESIGN

Prospective observational.

SETTING

Balance clinic in tertiary referral center.

PATIENTS

Patients referred with dizziness or imbalance as their primary complaint.

OUTCOME MEASURES

The modified Clinical Test for the Sensory Interaction on Balance scores as assessed by the Neurocom VSR Balance Master platform, the Dizziness Handicap Inventory, and the Health Utilities Index Marks 2 and 3.

RESULTS

One hundred fifty-nine patients were entered into the study. The mean age of participants was 54.5 years, with a female-to-male ratio of 2.1:1. The scores for the Dizziness Handicap Inventory and Health Utilities Index are similar between sexes, and although the Dizziness Handicap Inventory score did not correlate with age, Health Utilities Index 2 and 3 scores did show a negative correlation with increasing age. There are weak, positive correlations between the Dizziness Handicap Inventory and the firm surface conditions of the modified Clinical Test for the Sensory Interaction on Balance but no useful correlation with the foam conditions. Similar weak negative correlations were found between the Health Utilities Index 2 and 3 and the modified Clinical Test for the Sensory Interaction on Balance scores.

CONCLUSION

Patient-perceived handicap of imbalance appears to correlate poorly with assessment of postural stability using the modified Clinical Test for the Sensory Interaction on Balance.