Balance performance in head-shake computerized dynamic posturography: aging effects and test-retest reliability

Normative Values for the Head Shake Sensory Organization Test in an Active Duty Military Cohort

INTRODUCTION

The Head Shake Sensory Organization Test (HS-SOT) assesses postural stability while the head is moving and may also identify deficits in attention associated with the dual task conditions of moving the head at a specified speed while maintaining balance. Normative values for the HS-SOT have not been established in a healthy military population or other highly trained populations such as athletes. Establishing normative values in a military population will enable clinicians to compare the scores of patients with medical conditions that affect postural stability and sensory integration such as concussion or traumatic brain injury, vestibular dysfunction, or migraine to those of a healthy population to determine a need for intervention and for return to duty considerations. The purposes of this cross-sectional study were to establish normative values for the HS-SOT within the military population, to determine whether HS-SOT scores differed between men and women or among age groups, and to determine whether HS-SOT scores differed from scores on similar conditions of the Sensory Organization Test (SOT).

MATERIALS AND METHODS

Active duty service members (n = 237, 54 female) at Joint Base Lewis-McChord, Washington, Fort Campbell, Kentucky, and the National Capitol Region (Washington, D.C, Maryland, and Virginia) completed the SOT and HS-SOT on the NeuroCom® Balance Master™. Parametric and non-parametric comparisons were analyzed for the equilibrium scores for the SOT and HS-SOT conditions 2 (SOT-2, HS-SOT-2, respectively) and 5 (SOT-5, HS-SOT-5, respectively) and the equilibrium score ratios (ESRs) for HS-SOT-2 and HS-SOT-5 for the total sample, men and women, and age group categories (18-26 years, 27-35 years, and 36-45 years).

RESULTS

There were no differences in HS-SOT-2 or HS-SOT-5 equilibrium ratio scores between men (0.99 ±.029 and 0.83 ±0.25, respectively) and women (1.00 ±0.03 and 0.81 ±0.21, respectively). There were no differences in the SOT-2 equilibrium scores (F = 2.29, P = 0.10) or SOT-5 equilibrium scores (Kruskal-Wallis H = 3.26, P = 0.20) among the different age groups. SOT-2 equilibrium scores were higher than the HS-SOT-2 equilibrium scores (Z = -4.10, P < 0.001). SOT-5 equilibrium scores were also higher than HS-SOT-5 equilibrium scores (Z = -12.22, P < 0.001), and the HS-SOT-2 and HS-SOT-5 equilibrium scores differed from each other (Z = -13.26, P < 0.001).

CONCLUSIONS

This study established normative values for the HS-SOT in a military population. Equilibrium scores did not differ between men and women or among age groups, suggesting that these values can be used as reference points for most service members. Postural stability was found to be significantly challenged during head motion, indicating the HS-SOT is a valuable tool for identifying subtle impairments in postural stability. These findings have important implications for early detection and intervention in individuals with medical conditions affecting balance, particularly concussions or vestibular disorders.

Impact of Concussions on Postural Stability Performance Using the Head Shake-Sensory Organization Test

Background

A concussion is a traumatic brain injury that can result in vestibular and oculomotor dysfunctions. The Head Shake-Sensory Organization Test was developed from the original Sensory Organization Test to measure a subject's ability to maintain balance while moving their head.

Purpose

The purpose of this study was to compare the performance of adults with no history of concussion to those with a history of concussion on the Head Shake-Sensory Organization Test to determine if long-standing balance deficits are present after concussion.

Study Design

Cross-sectional study.

Methods

Subjects with a history of concussion and healthy normal controls completed the Dizziness Handicap Inventory, the Activities-Specific Balance Confidence Scale, the sensory organization test, the head shake SOT, and the Foam Head Shake-Sensory Organization test in a single testing session. Scores were analyzed for differences between the two groups.

Results

Twenty-five participants (nine patients with history of concussion and 16 healthy controls; mean age, 21.08±4.10 years) completed testing. The equilibrium scores in both groups significantly decreased with more complex tasks. Furthermore, the concussion group had significantly worse equilibrium scores than the control group during the Head Shake (p = 0.007) and Foam Head Shake-Sensory Organization Test (p = 0.002) tasks but not during the Sensory Organization Test task.

Conclusion

Adding head shake and foam cushion conditions to postural stability tests improves sensitivity in detecting balance deficits in individuals with a concussion.

Level of Evidence

3.

Investigation of Head Shake Sensory Organization Test (HS-SOT) in three planes: Test-retest reliability and age-related differences

BACKGROUND

In recent years, it has been determined that SOT sensitivity is insufficient in patients who develop vestibular compensation and therefore the Head Shake Sensory Organization Test (HS-SOT) has been developed.

RESEARCH QUESTION

How differs the balance performance of healthy adults that is tested with HS-SOT according to age and test planes? What is the test-retest reliability level of the HS-SOT in three planes?

METHODS

Our prospective study, which has a methodological research design, included 80 participants divided into three groups by age range (Group 1: 20-39 years (n = 30); Group 2: 40-49 years (n = 30) and Group 3: 50-64 years (n = 20)). SOT and HSSOT ( yaw, pitch, roll) were performed to all participants. To investigate the testretest reliability of the HS-SOT, a total of 27 participants were re-evaluated one week later. The HS-SOT performance of the participants was compared between age groups and test planes. Intra-class correlation coefficient and minimum detectable change values (MDC) was calculated to test-retest reliability of HS-SOT.

RESULTS

HS-SOT scores (HS-2 and HS-5) did not differ significantly between age groups. The balance performance of individuals for the pitch plane was lower than other planes. Only the HS-5 score showed a significant difference between the sessions. HS-5 scores were higher in the re-test; for the first group in the pitch plane and for the third group in the yaw plane. The test-retest reliability level of these conditions was "moderate-good" for both groups. The corresponding MDC value was highest (14.01) for the HS-5 (yaw) score of the elderly group.

SIGNIFICANCE

The findings from this study demonstrated that the test plane influences the HS-SOT, a learning/practice effect may occur because of repeated HS-SOT evaluation, and this effect is more explicit in the elderly. This study provides a perspective for the evaluation and follow-up processes of patients with balance problems.

A Comparison of Generalized and Individualized Vestibular Rehabilitation Therapy in a Military TBI Sample

OBJECTIVE

To compare clinical outcomes between active duty service members receiving generalized versus individualized vestibular rehabilitation treatment (GVRT and IVRT, respectively) for persistent vestibular-related symptoms following mild traumatic brain injury (mTBI).

SETTING

An outpatient TBI rehabilitation clinic.

PARTICIPANTS

Fifty-seven participants with persistent vestibular-related symptoms following mTBI were randomly assigned to the GVRT (n = 28) or IVRT (n = 29) group, stratified by dizziness-related impairment severity. Forty-two participants (n = 21 per group) completed the posttreatment evaluation and were included in analyses.

DESIGN

We employed a single-site, randomized, pre-/posttest experimental design. The GVRT program consisted of eight 45-minute group-based treatment sessions and IVRT consisted of three 30-minute one-on-one treatment sessions both to be completed within 8 weeks. Group assignment was not blinded to study personnel or participants. Research evaluations were completed approximately 2 weeks prior to treatment initiation and following treatment completion.

MAIN MEASURES

Outcome measures included Dizziness Handicap Inventory (DHI) and Activities-specific Balance Confidence Scale (ABC) total scores, Sensory Organization Test (SOT) composite equilibrium and sensory input ratio scores, Head Shake SOT (HS-SOT) conditions 2 and 5, and horizontal and vertical Dynamic Visual Acuity. Separate mixed-effects models were used to compare clinical outcomes between the GVRT and IVRT groups.

RESULTS

Both groups demonstrated significant improvement from pre- to posttreatment on self-reported dizziness-related impairment (DHI [F(1,41) = 16.28, P < .001]) and balance performance with and without head movement (composite equilibrium score [F(1,41) = 16.58, P < .001, effect size [ES] = 0.43], somatosensory [F(1,41) = 6.79, P = .013, ES = 0.26], visual [F(1,41) = 6.49, P = .015, ES = 0.29], vestibular [F(1,41) = 22.31, P < .001, ES = 0.55], and HS-SOT condition 5 [F(1,38) = 23.98, P < .001, ES = 0.64]). Treatment effects did not differ between groups on any of the outcome measures.

CONCLUSIONS

We provide preliminary evidence that differences in clinical outcomes do not exist between participants receiving generalized versus individualized VR. Further research is needed to determine comparative effectiveness between these 2 treatment approaches for persistent vestibular-related symptoms following mTBI.

Posturography with head movements in the assessment of balance in chronic unilateral vestibular lesions

The aim of our study was to validate the method of head-shake static posturography (HS-posturography) in healthy individuals and to establish the value of this novel method in the diagnostics of patients with unilateral vestibular lesion (UV). The study included 202 participants divided into two groups, one consisting of 133 patients with canal paresis CP > 19% and one of 69 healthy subjects. Participant was tested according to the standard protocol of static posturography (SP), and with head movements of 0.3 Hz (HS 40), 0.6 Hz (HS 70) in random order controlled by a metronome. HS-posturography revealed a similar repeatability and internal consistency as the standard posturography. In patients with UV, 4th condition revealed higher sensitivity (74%) and specificity (71%) in HS 40 than in the standard posturography (67%, 65% respectively) and HS 70 (54%, 70% respectively). Static posturography and HS- posturography revealed a high reliability of the testing method. The head movements added to static posturography improve the sensitivity and specificity of the method in group with vestibular impairment. The most important test for that purpose seems to be the one on unstable surface with the eyes closed, with low frequency of head movements.

Effects of head motion on postural stability in healthy young adults with chronic motion sensitivity

Background

Motion sensitivity, or motion sickness, is common in modern vehicular and visually stimulating environments. Several studies have shown a relationship between motion sensitivity and decreased postural stability. We aimed to evaluate the effects of head motion (horizontal and vertical) on postural stability in healthy adults with and without chronic motion sensitivity (CMS).

Methods

Sixty healthy adult men and women (age, 20–40 years) with CMS (CMS group, n = 30) and without CMS (non-CMS group, n = 30) participated in the study. Postural stability was assessed during three conditions (static, horizontal head motion, and vertical head motion) using computerized dynamic posturography. Group and condition-related differences in equilibrium scores were evaluated.

Results

There was no significant group x condition interaction (F_2,114 = 0.9, partial ƞ² = 0.04, p = 0.35). However, significant condition-related differences in equilibrium scores were observed (F_2,114 = 26.4, partial ƞ² = 0.31, p < 0.001). Equilibrium scores were significantly worse in the horizontal and vertical head motion conditions compared to those in the static condition (p < 0.001), but were comparable in vertical and horizontal head motion conditions (p = 0.27).

Conclusions

Postural stability was lower in the horizontal and vertical conditions compared to the static condition. However, horizontal and vertical head motions had comparable effects on postural stability in both CMS and non-CMS groups, contrary to our expectations.

Clinical significance of head shake movement in three planes in individuals with dizziness

PURPOSE

This study aims to evaluate the efficacy of head shake movement on three head movement planes (yaw, pitch and, roll) in patients with dizziness despite normal vestibular test results.

MATERIALS AND METHODS

Twenty individuals aged between 20 and 51 years with complaints of dizziness were included in the study, and their results were compared with the results from twenty age- and gender-matched controls. Participants were assessed using the Sensory Organization Test, Head Shake-Sensory Organization Test which is based on the modification of the Sensory Organization Test on the yaw, pitch, and roll planes, videonystagmography, caloric test, and Dizziness Handicap Inventory.

RESULTS

Significant differences were found in the yaw (p = 0.007), pitch (p < 0.001), and roll (p = 0.002) planes between the study and control groups of the Head Shake-Sensory Organization Test-5 scores. There were no statistically significant differences between the two groups of the Head Shake-Sensory Organization Test-2 scores in the yaw (p = 0.448), pitch (p = 0.213), and roll (p = 0.531) planes. When the sensitivity and specificity of Head Shake-Sensory Organization Test-5 conditions were examined, the highest specificity was observed in the pitch plane (100%), followed by the yaw (95%) and roll plane (95%).

CONCLUSION

Dynamic head movements are an important parameter for the evaluation of balance performance. The head shake modification could be used effectively in three-movement planes in individuals with dizziness.

A Novel Head Mounted Display Based Methodology for Balance Evaluation and Rehabilitation

In this paper, we present a new augmented reality (AR) head mounted display (HMD)-based balance rehabilitation method. This method assesses the individual’s postural stability quantitatively by measuring head movement via the inertial measurement unit sensor integrated in the AR HMD. In addition, it provides visual feedback to train through holographic objects, which interacts with the head position in real-time. We implemented applications for Microsoft HoloLens and conducted experiments with eight participants to verify the method we proposed. Participants performed each of three postural tasks three times depending on the presence or absence of augmented reality, the center of pressure (COP) displacement was measured through the Wii Balance Board, and the head displacement was measured through the HoloLens. There are significant correlations (p < 0.05) between COP and head displacement and significant differences (p < 0.05) between with/without AR feedback, although most of them were not statistically significant likely due to the small sample. Despite the results, we confirmed the applicability and potential of the AR HMD-based balance rehabilitation method we proposed. We expect the proposed method could be used as a convenient and effective rehabilitation tool for both patients and therapists in the future.

Critical Role of Somatosensation in Postural Control Following Spaceflight: Vestibularly Deficient Astronauts Are Not Able to Maintain Upright Stance During Compromised Somatosensation

The free-fall of orbital spaceflight effectively removes the gravitational vector used as a primary spatial orientation reference on Earth. Sustained absence of this reference drives adaptive changes in the internal perception-action models of the central nervous system (CNS), most notably in the processing of the vestibular otolith inputs. Upon landing, the return of the gravitational signal triggers a re-adaptation that restores terrestrial performance; however, during this period, the individual suffers from a functional vestibular deficiency. Here we provide evidence of a transient increase of the weighting of somatosensory inputs in postural control while the CNS resolves these vestibular deficiencies. Postural control performance was measured before and after spaceflight in 11 Shuttle astronauts and 11 matched controls and nine elderly who did not experience spaceflight. A quiet-stance paradigm was used that eliminated vision, modulated the lower extremity somatosensory cues by subtly modulating the orientation of the support surface beneath feet of subjects in all groups. Additionally, in astronauts and matched controls, we challenged the vestibular system with dynamic head tilts. Postural stability on the landing day (R+0) was substantially decreased for trials with absent visual and altered somatosensory cues, especially those also requiring dynamic head tilts ( ± 5° @ 0.33 Hz) during which 20/22 trials ended prematurely with a fall. In contrast, none of the astronauts fell during eyes-closed, dynamic head tilt trials with unaltered somatosensory cues, and only 3/22 trials resulted in falls with eyes-closed and altered somatosensory cues, but static upright head orientation. Furthermore, postural control performance of astronauts was either statistically not different or worse than that of healthy elderly subjects during the most challenging vestibular conditions on R+0. Overall, our results demonstrate a transient reweighting of sensory cues associated with microgravity-induced vestibular deficiencies, with a significant increase in reliance on somatosensory cues, which can provide an effective reference even without vision and with dynamic vestibular challenges. The translation of these results to aging population suggests that elderly individuals with visual and vestibular deficits may benefit from therapeutic interventions enhancing sensorimotor-integration to improve balance and reduce the risk of falling.

Efficacy of Balance and Eye-Movement Exercises for Persons With Multiple Sclerosis (BEEMS)

Objective

To determine whether a multifaceted vestibular-related rehabilitation program (Balance and Eye-Movement Exercises for Persons with Multiple Sclerosis; BEEMS) improves balance in persons with MS and whether there are differences in outcomes based on brainstem/cerebellar lesion involvement.

Methods

A 2-arm, examiner-blinded, stratified (involvement vs no involvement of brainstem/cerebellar structures), randomized controlled trial was implemented. Eighty-eight participants were allocated to BEEMS or no treatment control. Computerized Dynamic Posturography-Sensory Organization Test (CDP-SOT) measured balance control. The Dizziness Handicap Inventory (DHI), Modified Fatigue Impact Scale (MFIS), and Short Form-36 Health Status Questionnaire (SF-36) were also administered. Linear mixed models were used to investigate the primary and secondary aims.

Results

From baseline to 6 weeks, BEEMS participants experienced greater improvements compared to control participants in CDP-SOT composite (model-estimated difference in change 4.9, 95% confidence interval 1.39–8.38, p = 0.006), DHI total (−13.5, −17.7 to −7.25, p < 0.0001), MFIS total (−11.4, −15.7 to −7.0, p < 0.0001), SF-36 Mental (5.6, 2.43–8.71, p = 0.0006), and SF-36 Physical (3.5, 1.12–5.81, p = 0.004) scores and from baseline to 14 weeks in CDP-SOT composite (8.3, 4.73–11.9, p < 0.0001), DHI total (−13.9, −19.3 to −8.62, p < 0.0001), MFIS total (−12.3, −16.7 to −7.79, p < 0.0001), SF-36 Mental (3.9, 0.70–7.16, p = 0.02), and SF-36 Physical (3.2, 0.79–5.62, p = 0.01) scores. From baseline to 6 weeks, BEEMS participants with brainstem/cerebellar lesion involvement experienced greater improvements compared to those without in CDP-SOT composite (5.26, 0.34–10.2, p = 0.04) and MFIS total (−7.6, −14.0 to −1.33, p = 0.02) scores.

Conclusion

BEEMS improved multiple outcomes regardless of whether brainstem/cerebellar lesions were present, supporting the generalizability of BEEMS for ambulatory people with MS who have at least minimally impaired balance and fatigue.

Clinical trials.gov identifier

NCT01698086.

Classification of evidence

This study provides Class I evidence that BEEMS training improves dynamic posturography-based balance, dizziness, fatigue, and quality of life in persons with MS.

Unique approach to sensorimotor training with a new device combining air cushion with stochastic translations-A prospective randomized controlled clinical trial

Sensorimotor training with a wide variety of available devices represents an important component in rehabilitation and prevention of different sports injuries and chronic diseases. The purpose of this study was to evaluate the effects of a sensorimotor training with a newly developed device, which consists of an instable platform moving on an air cushion, providing dynamic balance training by tilting and unanticipated stochastic translations on postural control. Seventy-two healthy young subjects were included in this prospective, randomized, controlled, and observer-blinded study. Balance was objectively assessed by posturography and Functional Reach Test (FRT). Additionally we evaluated the subjective rating of balance. After randomization the sensorimotor training group performed a training program on the new device over a 5-6 week study period. After this time improvement in objective and subjective measurements as a result of training became evident. A significant difference in challenging posturographic parameters (Sensory Organization Test 5: training group 5.32±5.25 vs. control group 1.78±5.05, p=0.006 and Head Shake Sensory Organization Test 5: training group 11.94±8.97 vs. control group 5.41±10.17, p=0.01) as well as a significant difference in the FRT (training group 3.34±3.35cm vs. control group 0.01±2.97cm, p=0.0001) was found. Subjective assessment revealed a significant improvement in the participants' rating of balance and alteration of balance. Subjects showed a high satisfaction with the new training device. Our findings suggest that the newly developed device could be a promising option for sensorimotor training to improve postural control.

Modified head shake sensory organization test: Sensitivity and specificity

The Sensory Organization Test (SOT) of Computerized Dynamic Posturography (EquiTest™ equipment) is a valuable tool for investigating how an individual uses balance system sensory input (vestibular, vision, proprioception/somatosensory) to maintain quiet stance; however, it is limited as a screening tool for identifying peripheral vestibular system dysfunction. Previous research has shown that adding horizontal head-shake to portions of the standard SOT battery improved the identification of peripheral vestibular system asymmetry; however, flaws in the methods were noted. The objective of this work was to evaluate the sensitivity and specificity of the modified head-shake SOT (HS-SOT) protocol for identification of peripheral vestibular system lesion. Fifteen patients with chief complaint of instability, vertigo, and/or lightheadedness, with and without a caloric unilateral weakness (UW) and fifteen age-matched healthy controls were included in the final analysis. Ten of the 15 patients demonstrated a caloric UW≥25%. Participants completed standard conditions 2 and 5 of SOT with head still and during four horizontal head-shaking tasks (i.e., HS-SOT2-60°/s, HS-SOT2-120°/s, HS-SOT5-15°/s, and HS-SOT5-60°/s). Average equilibrium scores decreased as condition difficulty increased (SOT2, HS-SOT2-60°/s, HS-SOT2-120°/s, SOT 5, HS-SOT5-15°/s, and HS-SOT5-60°/s) for each group; as expected, a lower decline was noted for controls (slope=-6.59) compared to patients (slope=-11.69). The HS-SOT5-15°/s condition was superior for identifying peripheral vestibular asymmetry (AUC=0.90 sensitivity=70%, specificity=100%), with the strongest correlation to caloric UW% (rs=-0.743, p=0.000006). HS-SOT5-15°/s appears to be a promising screening measure for peripheral vestibular asymmetry.

Posturografia dinâmica computadorizada na avaliação do equilíbrio corporal de indivíduos com disfunção vestibular

Objetivo Avaliar o equilíbrio corporal de pacientes portadores de disfunção vestibular, por meio da posturografia dinâmica computadorizada. Métodos Estudo com 116 indivíduos com disfunção vestibular periférica, com idades entre 22 anos e 6 meses e 94 anos e 1 mês. Foram submetidos à avaliação otoneurológica completa, avaliação otorrinolaringológica, além da posturografia dinâmica computadorizada com os testes de organização sensorial, controle motor e de adaptação. Resultados O teste de organização sensorial foi o mais sensível para detectar alterações do equilíbrio e a condição 4, em que os pacientes permanecem na posição ortostática, com os pés afastados e sobre os sensores da superfície de referência, com os olhos abertos; condição 5, na qual os pacientes continuam na posição com os olhos fechados e a condição 6, em que os pacientes mantém os olhos abertos e o campo visual sofre deslocamentos anteroposteriores. Nas três condições, a superfície de referência oscila com movimentos similares à gangorra e foram as que os participantes apresentaram maiores dificuldades. Houve maior ocorrência de quedas se compararmos ao risco de quedas, avaliado quando o paciente tem pontuação entre 60 e 69 no índice de equilíbrio, principalmente a partir da condição 4 do teste de organização sensorial e entre os idosos. As mulheres tiveram maior número de quedas durante os testes. Conclusão A posturografia dinâmica computadorizada detectou as alterações relacionadas ao equilíbrio corporal, auxiliando no diagnóstico das disfunções e complementando a avaliação vestibular.

Integrated testing of standing balance and cognition: test-retest reliability and construct validity

Balance and cognitive impairments which are common with aging often coexist, are prognostic of future adverse health events, including fall injuries. Consequently, dual-task assessment programs that simultaneously address both stability and cognition are important to consider in rehabilitation and benefit healthy aging. The objective of this study was to establish test-retest reliability and construct validity of a dual-task computer game-based platform (TGP) that integrates head tracking and cognitive tasks with balance activities. Thirty healthy, community-dwelling individuals median age 64 (range 60-67) were recruited from a certified Medical Fitness Facility. Participants performed a series of computerized head tracking and cognitive game tasks while standing on fixed and sponge surfaces. Testing was conducted on two occasions, one week apart. Moderate to high test retest reliability (ICC values of 0.55-0.75) was observed for all outcome measures representing balance, gaze performance, cognition, and dual-task performance. A significant increase in center of foot pressure (COP) excursion was observed during both head tracking and cognitive dual-task conditions. The results demonstrate the system's ability to reliably detect changes related to specific and integrated aspects of balance, gaze, and cognitive performance.

Using the systems framework for postural control to analyze the components of balance evaluated in standardized balance measures: a scoping review

OBJECTIVE

To identify components of postural control included in standardized balance measures for adult populations.

DATA SOURCES

Electronic searches of MEDLINE, EMBASE, and CINAHL databases using keyword combinations of postural balance/equilibrium, psychometrics/reproducibility of results/predictive value of tests/validation studies, instrument construction/instrument validation, geriatric assessment/disability evaluation, gray literature, and hand searches.

STUDY SELECTION

Inclusion criteria were measures with a stated objective to assess balance, adult populations (18y and older), at least 1 psychometric evaluation, 1 standing task, a standardized protocol and evaluation criteria, and published in English. Two reviewers independently identified studies for inclusion. Sixty-six measures were included.

DATA EXTRACTION

A research assistant extracted descriptive characteristics and 2 reviewers independently coded components of balance in each measure using the Systems Framework for Postural Control, a widely recognized model of balance.

DATA SYNTHESIS

Components of balance evaluated in these measures were underlying motor systems (100% of measures), anticipatory postural control (71%), dynamic stability (67%), static stability (64%), sensory integration (48%), functional stability limits (27%), reactive postural control (23%), cognitive influences (17%), and verticality (8%). Thirty-four measures evaluated 3 or fewer components of balance, and 1 measure-the Balance Evaluation Systems Test-evaluated all components of balance.

CONCLUSIONS

Several standardized balance measures provide only partial information on postural control and omit important components of balance related to avoiding falls. As such, the choice of measure(s) may limit the overall interpretation of an individual's balance ability. Continued work is necessary to increase the implementation of comprehensive balance assessment in research and practice.

Vestibular functioning and migraine: pilot study comparing those with and without vertigo

Background:

The current study compared a migrainous vertigo group with a migraine without vertigo group. It was hypothesised that those with migrainous vertigo would have more abnormal test results during a non-migrainous period than those who suffer from migraine without vertigo.

Methods:

Both groups, comprising 10 participants each, were tested using: the gaze stabilisation test, dynamic visual acuity test, sensory organisation test, head shake sensory organisation test and functional gait assessment.

Results:

Eighteen females and 2 males aged 18–53 years participated. There were no significant differences between the two groups for the dynamic visual acuity test, sensory organisation test or head shake sensory organisation test. However, mean dynamic visual acuity loss was greater in both groups than in a normal population, and the head shake sensory organisation (sway) test was well below the normal mean. The functional gait assessment showed a significant difference (p = 0.0025) between the two groups.

Conclusion:

Both groups showed abnormalities in vestibular functioning compared with norms, suggesting that both had some degree of vestibular dysfunction. However, vestibular dysfunction was greater in the migrainous vertigo group than in the migraine without vertigo group, as evidenced by differences in functional gait assessment.

Vestibular functioning and migraine: comparing those with and without vertigo to a normal population

Objective:

This study compared vestibular functioning in a migrainous vertigo group, a migraine without vertigo group and a control group. It was hypothesised that the migrainous vertigo group would perform worse in tests of vestibular function and gait than the other groups during a non-migrainous period.

Methods:

Sixty-six participants (22 per group) were assessed using the head shake sensory organisation test, the gaze stabilisation test, the dynamic visual acuity test and the functional gait assessment. Separate analyses of variance and planned pair-wise comparisons (alpha = 0.05) were performed.

Results:

There was a difference between the results of the non-migraine group and the two migraine groups for the gaze stabilisation pitch test (p < 0.003), in which the control group showed faster head movement. There were also group differences in functional gait (p < 0.0001); the control group scored highest and the migrainous vertigo group scored lowest. There were no differences in the vestibular spinal reflex and balance tests.

Conclusion:

These findings indicate underlying differences in the vestibular ocular reflexes and function of migraine sufferers compared with those who do not suffer migraines, but the difference is most pronounced for those with migrainous vertigo. This suggests that vestibular rehabilitation for migrainous vertigo should focus on vestibular ocular reflexes and functional retraining.

Intraobserver reliability of posturography in patients with vestibular neuritis

The aim of the study was to establish the intraobserver reliability of a posturographic method in patients (n = 34) with vestibular neuritis. Intraclass correlation coefficients (relative reliability) for all parameters and test positions (ALL(mean)) ranged from 0.71 (95% CI: 0.41-0.85) to 0.92 (95% CI: 0.84-0.96). Absolute reliability (coefficient of variation) ranged between 3.1% (95% CI: 2.60-8.67) and 42.3% (95% CI: 40.7-74.5). Reliability of single test positions is much lower. The posturographic system showed good relative and satisfactory absolute intraobserver reliability for ALL(mean).

Intraobserver reliability of posturography in healthy subjects

Reliability of posturography is essential for the identification of intervention effects in any setting (e.g., sport, rehabilitation). The purpose was to establish the intraobserver reliability of a posturographic method in asymptomatic subjects (n = 30). Intraclass correlation coefficients (relative reliability) for every parameter and all test positions (ALL(mean)) ranged from 0.78 (95% CI: 0.53-0.90) to 0.95 (95% CI: 0.89-0.97). Absolute reliability, quantified by using the coefficient of variation, ranged between 3.5 and 19.8. Reliability of single test positions is much lower. The posturographic system showed good relative and satisfactory absolute intraobserver reliability for ALL(mean).