Vestibular Conditions Research Articles

A review of parameter settings for galvanic vestibular stimulation in clinical applications

Galvanic Vestibular Stimulation (GVS) is a method of manipulating the vestibular system through non-invasive electrical current. Depending on how GVS is applied, it produces specific sensations related to vestibular mediated central pathways. The method has been tested for decades for both medical and non-medical applications and has demonstrated promise in treating a variety of disorders including peripheral vestibular conditions, central vestibular pathology due to neurodegenerative diseases, and post-stroke motor rehabilitation. As GVS continues to grow in popularity and applications, the field lacks clarity on appropriate stimulation parameters, despite their importance for safe and efficacious neuromodulation. This study aims to review the parameters used in various treatment applications while also providing a concise overview of the mechanisms underlying GVS thereby offering essential context and justification for the chosen parameters. We performed a literature search on the PubMed and Embase databases for clinical trials including the term “galvanic vestibular stimulation.” After removing duplicates, secondary analyses, and studies that did not use GVS for therapeutic purposes, we were left with 53 independent studies. We extracted the stimulation parameters used in each study and report them here. The results of this review suggest that while some stimulation parameters are relatively standardized for specific treatment indications, others lack universally accepted guidelines as the field of GVS continues to evolve. Based on our findings, we recommend that future GVS research include at least one sham condition, the use of individualized current intensity, and the comparison of multiple GVS parameters within the same trial.

Development of the continuous ambulatory vestibular assessment (CAVA) system to provide an automatic diagnosis for vestibular conditions: protocol for a multicentre, single-arm, non-randomised clinical trial

IntroductionDizziness is a common symptom that can occur in an unpredictable and episodic manner leading to the imprecise reporting of symptoms. Patients will often see many specialists before receiving a...

Exercise With Unstable Objects: A Descriptive Survey Among Health Care and Fitness Professionals

Exercise with unstable objects is a popular intervention used by health care and fitness professionals. Understanding different professional beliefs and usage patterns might provide insight for future research and development of evidence-based guidelines. The purpose of this survey study was to document the perceptions, beliefs, and the use of exercise with unstable objects among health care and fitness professionals in the United States. Six hundred and sixteen respondents completed the survey. Most respondents used unstable objects for musculoskeletal postinjury fitness/return to performance (72%). Most believed the main therapeutic effects were enhanced motor control (88%), balance (86%), and somatosensory (85%) function. Most reported using the foam pad (80%) and BOSU (84%). The most used subjective measure was the Activities-specific Balance Confidence scale. Most respondents used single limb stance (85%) to measure static motor control and the single leg squat assessment (51%) for dynamic motor control. Respondents used variables such as dynamic movement, repetition and sets, and time during training. Respondents considered recent injury or surgery and neurological or vestibular conditions as the top precautions. Respondents considered acute injury or surgery and neurological or vestibular conditions as the top contraindications. This survey provides insight into health care and fitness professionals perceptions, beliefs, and use of exercise with unstable objects.

Comparing in-clinic versus telehealth for vestibular physical therapy.

Vestibular rehabilitation (VR) is a commonly employed treatment method for disorders of dizziness and imbalance. Access to a clinic for rehabilitation appointments can be challenging for a person experiencing dizziness. Telehealth may offer a comparable alternative to clinic-based VR for some patients. The objective of this study was to determine the efficacy of telehealth-based VR compared to traditional clinic-based VR, as measured with the Dizziness Handicapped Inventory (DHI) in a retrospective sample of patients with vestibular conditions. This is a retrospective, multi-institutional review from May 2020 to January 2021. Three study groups were analyzed: a telehealth group, a hybrid group, and a clinic based control group. Treatment efficacy was measured using the DHI. A repeated measures ANCOVA was performed to compare changes between the groups and across timepoints. The repeated measures ANCOVA was not significant for the interaction of groups (control, telehealth, and hybrid) by time (pre and post) (p > 0.05). However, there was a significant main effect for time (pre and post) (p < 0.05). Specifically, all groups improved DHI scores from pre to post treatment with mean differences of control: 31.85 points, telehealth: 18.75 points, and hybrid: 21.45 points. Findings showed that in-clinic, telehealth, and hybrid groups demonstrated a decrease in DHI scores, indicating self-reported improvements in the impact of dizziness on daily life. Continued research is recommended to explore the efficacy of using telehealth in assessing and treating vestibular conditions.

Medical record prompts improve the frequency and documentation of dizziness and driving conversations in the ENT balance clinic.

Driving capacity is affected by vestibular disorders and the medications used to treat them. Driving is not considered during medical consultations, with 92 per cent of patients attending a centre for dizziness not discussing it with the doctor. To investigate if medical record prompts facilitate dizziness and driving conversations in ENT balance clinics. A questionnaire was designed to reflect the current standards of practice and advice given regarding driving and dizziness during balance clinic consultations. Medical record prompts facilitated the improved frequency and recording of shared decision-making conversations about driving and dizziness in 98 per cent of consultations. This study highlights the benefits of medical record prompts for documented and accurate shared decision-making conversations surrounding dizziness, vertigo, vestibular conditions and driving. This potentially improves safety for all road users, and protects the patient and clinician in the event of road traffic accidents and medico-legal investigations.

Pitfalls, patience and patients: developing a physiotherapy-led balance clinic.

Balance dysfunction and vestibular conditions are major problems requiring significant resources. There is significant national and international variation in management pathways for such patients. This paper outlines a collaborative project run by the ENT department and two vestibular rehabilitation trained physiotherapists to establish a clinic to manage patients referred to ENT with vestibular and/or balance complaints. As part of a six-month pilot, two physiotherapy-led balance clinics were provided per week. A total of 159 new patients were seen, with only 15 needing ENT consultant input. This led to the successful creation of substantive posts; the clinic has seen 698 patients in its first two years. Patient outcomes and experience have been positive, and accompanied by reduced waiting and in-service times. The authors discuss some of the pitfalls, challenges and opportunities of developing this type of clinic.

Clinical Trajectories of Comorbidity Associated With Military-Sustained Mild Traumatic Brain Injury: Pre- and Post-Injury.

In the US military, traumatic brain injury (TBI) is of distinct importance, at home and in the deployed setting, and is considered a "signature injury of the wars in Afghanistan and Iraq." Since 2000, an estimated 468 424 service members (SMs) have been diagnosed with at least one TBI. We examined the clinical trajectories of a group of 18 comorbidities before and after a military-sustained mild TBI (mTBI). Without making assumptions on causality, a group of 18 conditions often co-occurring with mTBI were identified through literature review and TBI subject matter workgroup consensus. Using data from Military Health System Data Repository, we identified SMs whose first lifetime military mTBI occurred between October 1, 2016, and October 30, 2019. Correlation analyses were used to determine the linear relationship between comorbidities prior to and after mTBI diagnosis. Changes in the period prevalence of comorbidities was calculated. We identified 42 018 SMs with a first lifetime military mTBI, of which 77.6% had at least one comorbidity. Identified SMs were mostly young (46.1% ages 18-24 years), male (81.4%), and White (64.1%). Up to 180 days prior to an mTBI, the most frequently identified conditions were sleep-related conditions (21.7%), headaches (19.4%), posttraumatic stress disorders (PTSDs) (17.8%), anxiety disorders (11.3%), and cervicogenic disorders (eg, cervicalgia) (10.9%). In the period following mTBI diagnosis, the prevalence of diagnosed conditions increased, especially for visual disturbances (327.2%), cognitive conditions (313.9%), vestibular conditions (192.6%), those related to headache (152.2%), and hearing (72.9%). Sleep-related conditions showed moderate positive correlation with a group of co-occurring conditions, led by cognitive conditions ( ϕc = 0.50), anxiety disorders ( ϕc = 0.42), PTSDs ( ϕc =0.43), and headaches and related conditions ( ϕc = 0.38). Results indicate that caring for SMs with mild TBI requires a holistic approach, one that considers the complex nature of SM conditions, prior to sustaining their mTBI, as well as after injury. We found a complex correlation of conditions that suggest SMs with mTBI are undergoing a multifaceted experience, one that may require the development of a targeted multidimensional clinical practice recommendation and practice.

Visual vertigo and motion sickness is different between persistent postural-perceptual dizziness and vestibular migraine

IntroductionPersistent postural-perceptual dizziness (PPPD) and vestibular migraine (VM) share symptoms of visual vertigo and motion sickness that can be confusing for clinicians to distinguish. We compare the severity of these symptoms and dynamic subjective visual vertical (dSVV) in these two common vestibular conditions. MethodTwenty-nine patients with PPPD, 37 with VM, and 29 controls were surveyed for subjective symptoms using the visual vertigo analogue scale (VVAS) and motion sickness susceptibility questionnaire during childhood (MSA) and the past 10 years (MSB). dSVV is a measure of visual dependence measures perception of verticality against a rotating background (5 deg./s). ResultsVVAS revealed contextual differences for dizziness between those with PPPD and VM. Ratings of visual vertigo were most severe in PPPD, less in VM, and mild in controls (VVAS PPPD 27.1, VM 11.2, control 4.6, p < 0.001). MSA was more severe in VM than in PPPD or control (12.8 vs 7.6 vs 8.5, p = 0.01). MSB was more severe in VM than controls (MSB score 12.9 VS 8.1 p = 0.009) but was not different than PPPD (MSB score 10.0, p = 0.10). dSVV alignment was similar among the three groups (p = 0.83). Both VM and PPPD groups had greater simulator sickness than controls after completing the dSVV. ConclusionsPatients with PPPD report more visual vertigo than those with VM, but a history of motion sickness as a child is more common in VM. Additionally, the environmental context that induces visual vertigo is different between PPPD and VM.

The cost of untreated vestibular conditions: the role of otolaryngology &amp; rehabilitation

It is estimated that dizziness, vertigo, and falls are the third most common complaints heard by physicians from all age groups only proceeded by headache and lower back pain.1 Equilibrium disorders can affect individuals throughout the lifespan resulting from congenital, familial to acquired conditions. The symptoms from most acquired conditions, however, are the number one complaint of patients aged 65 years and older.2 This is further demonstrated by the number one fear of older adults is loss of independence and ability to age in place. This is strongly associated with fear of falling. Given the exponential growth of this older cohort group worldwide, this is a significant and growing segment of the population. This older population is also confronted with numerous medical co-morbidities complicating their management with the increased prevalence of falls. This contributes to considerable morbidities and mortality, with balance-related falls being the number one cause of accidental death for this population.3 This paper will review the high cost of undiagnosed and untreated vestibular-balance conditions, versus the cost savings of early detection, assessment and intervention and the role of otolaryngology and audio-vestibular medical specialists.

Visually enhanced vestibulo-ocular reflex gain in patients with vestibular disease.

Vestibular migraine (VM) is a diagnostic challenge. Visually enhanced vestibulo-ocular reflex (VVOR) gain, a measure of the visual-vestibular interaction, has been proposed as a tool for diagnosing VM. This study seeks to evaluate VVOR gain's diagnostic capability to predict VM and to compare the phenotypes of vestibular patients with elevated versus normal/low VVOR gain. A retrospective review of consecutive adult patients at a dizziness clinic from October 2016 and December 2020 was conducted. VVOR gain's diagnostic performance was assessed with the area under the receiver operating characteristic (AUROC) analysis. Demographic factors and clinical presentations were compared between vestibular patients with elevated versus normal/low VVOR gain. One hundred forty patients (70 with VM) were analyzed. VVOR gain was elevated in 68.6% of patients with VM, compared to 52.9% of patients without VM (p = .057). The AUROC of VVOR gain was 0.5902 (95% confidence interval: 0.4958-0.6846). Vestibular patients with elevated VVOR gain were younger than those with normal/low VVOR gain (mean age 50 vs. 62, p < .0001). A higher proportion of subjects with elevated VVOR gain had symptoms triggered by certain foods (17.6% vs. 5.5%, p = .040) and experienced sound sensitivity (34.1% vs. 18.2%, p = .040) and motion sensitivity (23.5% vs. 9.1%, p = .041). A greater proportion of VM patients with elevated VVOR gain were triggered by certain foods (27.1% vs. 0%, p = .006). VVOR gain alone has limited ability to discriminate VM from other vestibular conditions and must be interpreted carefully. VVOR gain elevation may be associated with food triggers and motion and sound sensitivity. IV.

The Relationship Between Measures of Postural Control in Concussion Assessment.

To determine the relationship between postural sway performance during commonly utilized postural control assessments following a concussion, including the modified Balance Error Scoring System (mBESS), concussion balance test (COBALT), and sensory organization test (SOT) in healthy young adults. Twenty participants completed all balance testing. The mBESS conditions included double limb stance, single limb stance, and tandem stance. The COBALT was comprised of yaw plane head shake (HS) and vestibular ocular reflex cancellation conditions performed on firm and foam surfaces. Subjects performed 6 conditions of the SOT (C1-C6), which systematically perturbed sensory inputs. Postural sway performance was measured using a single force plate and quantified as a sway score for the mBESS and COBALT, and an equilibrium score for the SOT. Spearman rank correlations were used to examine the relationship between postural sway performance for each test. There was a moderate positive correlation between mBESS-tandem stance and the HS on foam COBALT condition (r = .643, P = .002). There was a moderate negative correlation between mBESS-double limb stance and SOT-C6 (r = -.512, P = .021), and between mBESS-single limb stance and SOT-C6 (r = -.523, P = .018). The COBALT and SOT demonstrated numerous moderate to good negative correlations (r = -.448 to -.708, P ≤ .05), including a good negative correlation between HS on foam and SOT-C1 (r = -.725, P = .0003). Performance on the mBESS had minimal relationship to performance on the COBALT and SOT, suggesting that the clinical standard may not challenge sensory integration at the same capacity as other tests. All COBALT conditions had fair to good associations to at least 2 SOT conditions, suggesting both assessments are representative of sensory integration. Further investigation of the current clinical approach is warranted as the COBALT may be a clinically feasible test of sensory integration.

Visual stress responses to static images are associated with symptoms of Persistent Postural Perceptual Dizziness (PPPD).

Images that deviate from natural scene statistics in terms of spatial frequency and orientation content can produce visual stress (also known as visual discomfort), especially for migraine sufferers. These images appear to over-activate the visual cortex. To connect the literature on visual discomfort with a common chronic condition presenting in neuro-otology clinics known as persistent postural perceptual dizziness (PPPD). Patients experience dizziness when walking through highly cluttered environments or when watching moving stimuli. This is thought to arise from maladaptive interaction between vestibular and visual signals for balance. We measured visual discomfort to stationary images in patients with PPPD (N = 30) and symptoms of PPPD in a large general population cohort (N = 1858) using the Visual Vertigo Analogue Scale (VVAS) and the Situational Characteristics Questionnaire (SCQ). We found that patients with PPPD, and individuals in the general population with more PPPD symptoms, report heightened visual discomfort to stationary images that deviate from natural spectra (patient comparison, F (1, 1865) = 29, p < 0.001; general population correlations, VVAS, rs (1387) = 0.46, p < 0.001; SCQ, rs (1387) = 0.39, p < 0.001). These findings were not explained by co-morbid migraine. Indeed, PPPD symptoms showed a significantly stronger relationship with visual discomfort than did migraine (VVAS, zH = 8.81, p < 0.001; SCQ, zH = 6.29, p < 0.001). We speculate that atypical visual processing -perhaps due to a visual cortex more prone to over-activation -may predispose individuals to PPPD, possibly helping to explain why some patients with vestibular conditions develop PPPD and some do not.

Sex Moderates the Relationship between Perceptual-Motor Function and Single-Leg Squatting Mechanics.

To examine the isolated and combined effects of sex and perceptual-motor function on single-leg squatting mechanics in males and females. We employed a cross-sectional design in a research laboratory. Fifty-eight females (22.2 ± 3.5 yrs, 1.60 ± .07 m, 64.1 ± 13.0 kg) and 35 males (23.5 ± 5.0 yrs, 1.80 ± .06m, 84.7 ± 15.3 kg) free from time-loss injury in the six months prior, vertigo, and vestibular conditions participated in this study. Independent variables were sex, perceptual-motor metrics (reaction time, efficiency index, conflict discrepancy), and interaction effects. Dependent variables were peak frontal plane angles of knee projection, ipsilateral trunk flexion, and contralateral pelvic drop during single-leg squatting. After accounting for the sex-specific variance and perceptual-motor function effects on frontal plane squatting kinematics, female sex amplified the associations of: higher reaction time, lower efficiency index, and higher conflict discrepancy with greater right ipsilateral peak trunk lean (R2 = .13; p = .05); higher reaction time, lower efficiency index, and higher conflict discrepancy with decreased right contralateral pelvic drop (R2 = .22; p < .001); higher reaction time and lower conflict discrepancy with greater right frontal plane knee projection angle (R2 = .12; p = .03); and higher reaction time with greater left frontal plane knee projection angle (R2 = .22; p < .001). Female sex amplified the relationship between perceptual-motor function and two-dimensional frontal plane squatting kinematics. Future work should determine the extent to which perceptual-motor improvements translate to safer movement strategies.

A Survey of Entry-Level Physical Therapy Education Content for Vestibular Rehabilitation

Introduction. Vestibular rehabilitation (VR) represents an evolving area of physical therapy practice and is therefore pertinent to entry-level education. Currently, there is no consensus regarding the extent of content that should be covered in entry-level Doctor of Physical Therapy (DPT) programs. The first step in establishing standards of education in VR is to determine what content is currently taught and what is perceived to be important. The purpose of this study was to survey entry-level DPT programs as to what VR content is included in their curriculum and their perceptions of importance of VR examination and intervention techniques. Methods. Directors of 229 accredited physical therapy education programs in the United States were contacted to complete the survey. A task force of 3 clinicians and 4 faculty used a modified Delphi process to select survey items to examine content exposure, student assessment, and a rating for overall expected expertise. Modifications were made to the final survey for clarity and time requirements based on pilot survey data. Descriptive and correlational statistics were applied to the data. Results. Ninety-nine programs (43.23%) responded to the survey. More than 90% rated 7 vestibular conditions (unilateral vestibular hypofunction, posterior semicircular canal canalithiasis and cupulolithiasis, vestibular neuritis, labyrinthitis, bilateral vestibular hypofunction, and horizontal semicircular canal canalithiasis) as essential for entry-level practice. More than 90% of respondents rated all elements of clinical application and decision-making as essential for entry-level education except for billing/diagnosis codes. Most respondents expected students to perform at the intermediate or advanced beginner level in vestibular assessment and rehabilitation on graduation. Discussion and Conclusion. Disparities in VR content, expected level of performance, and the amount of time dedicated to VR exist. Vestibular rehabilitation education may not match current clinical practice. Future research should determine the level of education clinicians expect of entry-level DPT graduates.

Influence of sex hormones on vestibular disorders.

Vestibular disorders are gender distributed with a higher prevalence in women. Although research has increased in this field, the mechanisms underlying this unbalance is unclear. This review summarises recent advances in this research sphere, and briefly discusses sex hormone effects on various vestibular conditions and highlights some recent theories. Recent work has identified a direct link between aberrant gonadal hormone levels and vestibular dysfunction. Benign paroxysmal positional vertigo research suggests that the disorder may be linked to the rapid decrease in oestrogen, observed in menopausal women, which disrupts otoconial metabolism within the inner ear. A successful hormonal therapeutic intervention study has advanced our knowledge of hormonal influences in the inner ear in Ménière's disease. Also, several studies have focused on potential mechanisms involved in the interaction between Vestibular Migraine, Mal de Debarquement Syndrome, and gonadal hormones. In females, gonadal hormones and sex-specific synaptic plasticity may play a significant role in the underlying pathophysiology of peripheral and central vestibular disorders. Overall, this review concludes that clinical assessment of female vestibular patients requires a multifaceted approach which includes auditory and vestibular medicine physicians, gynaecologists and/or endocrinologists, in conjunction with hormonal profile evaluations.

VESTIBULAR TESTING IN CHILDREN WITH DIZZINESS AND BALANCE CONCERNS AFTER CONCUSSION: LABORATORY AND CLINICAL RESULTS

Background:Dizziness is the second most common symptom in people who sustain a concussion and there are few reports on vestibular laboratory findings in the concussed pediatric population. Studies to date have shown conflicting findings regarding incidence of peripheral vestibular disorders. Hypothesis/Purpose: The purpose of this study is to report vestibular laboratory and clinical examination findings in concussed youth referred to a multidisciplinary vestibular clinic.Methods:A retrospective chart review was performed for all patients (n=474) seen from August 2017 to March 2020 for a single comprehensive examination in a multidisciplinary pediatric vestibular specialty clinic. Data was extracted from the charts of patients (n=64) with a history of concussion referred because of chronic dizziness and/or imbalance. Each patient was examined by a neurotologist, physical therapist, and audiologist with specialized training in vestibular disorders. Vestibular laboratory testing performed by audiologists included video nystagmography (VNG) evaluation of oculomotor function and BPPV, rotational chair, video head impulse test (vHIT), vestibular evoked myogenic potentials (VEMPs), post-headshake nystagmus, and caloric irrigation. Physical therapy clinical examination included dynamic visual acuity testing (DVA), vestibular/oculomotor screening (VOMS), and sensory organization test (SOT). Not all tests were performed on every patient secondary to factors such as insurance coverage, patient tolerance, and young age.Results:1 or more components of VOMS was abnormal in 30 of 53 patients examined. DVA was completed on 40 patients, 23 of which were reported as abnormal. SOT was completed on 46 patients, 18 of which demonstrated below normal composite equilibrium scores. Laboratory findings were as follows: VEMPs (n=50) were normal in all but 1 patient, vHIT (n=59), caloric irrigation (n=26), post-headshake nystagmus (n=49), and positional testing (n=55) were normal on all patients tested. Rotational chair (n=60) was performed at 4 different frequencies and revealed low gain in 3 patients.Conclusion:Vestibular laboratory examination was normal in nearly all subjects tested. These results suggest that in concussed youth with chronic dizziness and/or imbalance, laboratory vestibular test outcomes indicative of peripheral dysfunction are rare, which contradicts previous research in this population. In contrast, clinical vestibular assessment was abnormal in more than 50% of subjects examined which suggests that clinicians should use caution interpreting clinical examination findings for diagnosing peripheral vestibular dysfunction. Abnormal clinical examination findings may be indicative of central vestibular conditions such as space and motion intolerance and PPPD in chronically dizzy pediatric patients after concussion.Tables/Figures:

Role of somatosensory and/or vestibular sensory information in subjective postural vertical in healthy adults

The body's subjective postural vertical (SPV) has been thought to be affected by somatosensory information. How the SPV is perceived based on what types of somatosensory information has not been determined experimentally by manipulating somatosensory conditions. We investigated the effects of disturbing the somatosensory information from a seat pad and/or vestibular sensory information on the SPV in 15 healthy adults. Their SPV values were measured under four conditions (control, somatosensory, vestibular, and somatosensory + vestibular) in random order. The average and absolute SPV values were measured. In the somatosensory condition, a foam rubber pad was placed on the seating surface and the subject's SPV was measured. In the vestibular condition, the SPV was measured during galvanic vestibular stimulation (GVS). The somatosensory + vestibular condition was used to measure the SPV during combined somatosensory and vestibular stimulation. The mean SPV value was significantly increased in the somatosensory + vestibular condition compared to the other three conditions. The absolute value of SPV was significantly increased in the somatosensory and somatosensory + vestibular conditions compared to the control and vestibular conditions. There was no significant difference in the average or absolute SPV values in the vestibular condition compared to the other conditions. There was no significant difference between SPV errors when somatosensory information was disturbed or when somatosensory + vestibular information was disturbed. When the somatosensory information from the seat was disturbed, the SPV error increased, and it also shifted under the influence of the vestibular sensory information modulation. These results indicate that somatosensory information from the seat plays an important role in SPV in healthy adults.

Full-body ownership illusion elicited by visuo-vestibular integration.

Vestibular signals allow us to maintain balance and orient ourselves in space. However, the possible contribution of the vestibular sense to the perception of the body as one's own (body ownership) remains poorly understood. The aim of the present study was to investigate how vestibular information contributes to the experience of body ownership using multisensory integration. We conducted 3 studies using a "full-body ownership illusion" induced by virtual reality technology and galvanic vestibular stimulation (GVS); the latter is a technique that allows for the selective stimulation of vestibular afferents. Participants wearing head-mounted displays saw a mannequin's body that was performing a slow swinging movement from a first-person perspective. At the same time, participants were exposed to GVS that elicited vestibular sensations of swinging whole-body movements in the corresponding direction. Perceived ownership of the seen body was measured using questionnaire ratings and skin-conductance responses to a knife threat toward the mannequin. We demonstrated that when participants were exposed to congruent visuo-vestibular information, they perceived a stronger ownership of the mannequin's body compared with when they were exposed to unimodal visual and vestibular conditions or an incongruent visuo-vestibular condition. The findings show that visuo-vestibular congruency is sufficient to increase the feeling of illusory body ownership of a mannequin's body. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Acute Dizziness.

Dizziness is a common chief complaint with an extensive differential diagnosis that includes both benign and serious conditions. Physicians must distinguish the majority of patients who suffer from self-limiting conditions from those with serious illnesses that require acute treatment. The preferred approach to the diagnosis of an acutely dizzy patient emphasizes different aspects of the history to guide a focused physical examination, with the goal of differentiating benign peripheral vestibular conditions from dangerous posterior circulation strokes. Currently, misdiagnoses are frequent and diagnostic testing costs are high. This partly relates to use of an outdated diagnostic paradigm. This commonly used traditional approach relies on dizziness "symptom quality" or "type" (vertigo, presyncope, disequilibrium) to guide inquiry. It does not distinguish benign from dangerous causes and is inconsistent with current best evidence. A better approach categorizes patients into three groups based on timing and triggers. Each category has its own differential diagnosis and targeted bedside approach: (1) acute vestibular syndrome, where bedside physical examination differentiates vestibular neuritis from stroke; (2) spontaneous episodic vestibular syndrome, where associated symptoms help differentiate vestibular migraine from transient ischemic attack; and (3) triggered episodic vestibular syndrome, where the Dix-Hallpike and supine roll test help differentiate benign paroxysmal positional vertigo from posterior fossa structural lesions. The "timing and triggers" diagnostic approach for the acutely dizzy derives from current best evidence and offers the potential to reduce misdiagnosis while simultaneously decreasing diagnostic test overuse, unnecessary hospitalization, and incorrect treatments.

Effects of backpack and double pack loads on postural stability

Measurement of postural stability is crucial for identifying predictors of performance, determining the efficacy of physical training and rehabilitation techniques and evaluating and preventing injuries, particularly for heavy load carriage in hikers, mountain search and rescue personnel and soldiers. This study investigated the effect of load distribution on postural stability in an upright stance using backpack and double pack loads under conflicting or impaired somatosensory, visual and vestibular conditions. The sensory organisation tests were conducted on 20 young adults before and after a 10-min level walking exercise. Young adults’ ability to use inputs from somatosensory and visual systems to maintain postural stability was significantly reduced following a 10-min walking exercise with a heavy backpack (30% of body weight), whereas no significant changes were observed for double pack carriage. Thus, the distribution of heavy loads to the front and back provides superior balance control compared with back-only loading. Practitioner summary: This study investigated the effects of heavy (30% of body weight) load distribution on postural stability after a 10-min walking exercise. Backpack carriage significantly reduced postural stability, whereas there was no significant effect under double pack loads. Distribution of heavy loads on the front-and-back is desirable for superior balance control.