Relationship Between Sensory Organization Testing Scores With Lower Extremity Injuries and Prior Concussion in Professional Soccer Players.

OBJECTIVE: To evaluate for associations between concussion history or lower extremity (LE) injury and computerized sensory organization testing (SOT) performance in professional soccer players. DESIGN: Cross-sectional study. SETTING: Tertiary care center. PARTICIPANTS: Thirty-three, professional, male soccer players on an American club, between the years 2019 and 2021. ASSESSMENT OF RISK FACTORS: Player age, history of reported LE injury (gluteal, hamstring, ankle, knee, hip, groin, and sports hernia), history of diagnosed concussion, and the number of prior concussions were documented for each player. MAIN OUTCOME MEASURES: Baseline SOT of postural sway was conducted in 6 sensory conditions for all players. RESULTS: Eleven athletes (33%) reported a previous concussion, and 15 (45%) reported a previous LE injury. There were no significant differences in SOT scores between those with and without a previous diagnosis of concussion ( P > 0.05). Those reporting a previous LE injury performed better on condition 3 (eyes open, unstable visual surround) than those who did not ( P = 0.03). Athletes aged 25 years or younger performed worse on condition 3 ( P = 0.01) and had worse, although not statistically significant, median performance on all other balance measures than those older than 25 years. Intraclass correlation coefficient for repeat SOT assessment was 0.58, indicating moderate reliability, without an evident practice effect. CONCLUSIONS: Professional soccer players with a previous concussion or history of LE injury did not demonstrate long-term deficits in postural control, as assessed by multiyear computerized SOT baseline testing. The SOT was reliable over time with younger athletes exhibiting greater postural sway than older athletes.

A continuing clinical education course to maintain clinical competencies and foster new clinical knowledge during the graduate school years of MD-PhD training.

Introduction: Most students in MD-PhD programs take a leave of absence from medical school to complete PhD training, which promotes a natural loss of clinical skills and knowledge and could negatively impact a student's long-term clinical knowledge. To address this concern, clinical refresher courses in the final year of PhD training have traditionally been used; however, effectiveness of such courses versus a longitudinal clinical course spanning all PhD training years is unclear. Methods: The University of Alabama at Birmingham MD-PhD Program implemented a comprehensive continuing clinical education (CCE) course spanning PhD training years that features three course components: (1) clinical skills; (2) clinical knowledge; and (3) specialty exposure activities. To evaluate course effectiveness, data from an anonymous student survey completed at the end of each semester were analyzed. Results: Five hundred and ninety-seven surveys were completed by MD-PhD students from fall 2014 to 2022. Survey responses indicated that the majority of students found the course helpful to: maintain clinical skills and knowledge (544/597, 91% and 559/597, 94%; respectively), gain exposure to clinical specialties (568/597, 95%), and prepare them for responsibilities during clinical clerkships. During semesters following lockdowns from the COVID-19 pandemic, there were significant drops in students' perceived preparedness. Conclusions: Positive student survey feedback and improved preparedness to return to clinic after development of the course suggests the CCE course is a useful approach to maintain clinical knowledge during research training.

Orthostatic intolerance in post-concussion patients.

Orthostatic intolerance (OI) following pediatric concussion is not well understood. Assessing the prevalence of concussion-related OI and how it compares to non-concussion-related OI will improve care for patients suffering with these symptoms. OBJECTIVE: We set out to describe concussion-related OI in adolescence, with particular emphasis on time to recovery and differences from non-concussion-related OI (including male vs. female prevalence). Retrospective chart reviews were completed on post-concussion patients endorsing symptoms of OI. The patients' sex, sport history, previous concussions, time since injury, and recovery time were analyzed and compared between males and females as well as against general OI statistics. Thirty-nine pediatric patients, representing 8.7% of all new patients referred to a specialized concussion clinic over a 13-month interval, were included in the chart review. Mean age of onset was 15.0 ± 2.5 years and 18 (46%) were males. The median times from evaluation to symptom resolution were 120 days. Of 18 patients who completed head-up tilt table testing, 17 (94%) had orthostatic tachycardic response (>40 bpm heart rate increment). Post-concussive OI differs from other orthostatic intolerance etiologies, lacking a strong female predominance and exhibiting a shorter time course to recovery compared to other etiologies of OI (but longer recovery time compared to concussion patients in general). Clinical orthostatic vital signs may not be sensitive for diagnosing orthostatic intolerance in athletes, likely due to higher vagal tone and more efficient skeletal muscle pump.

Cognitive and Central Vestibular Functions Correlate in People With Multiple Sclerosis.

Background. Cognitive impairment is common, but poorly managed in people with multiple sclerosis (MS). Balance has been correlated with cognition in people with MS, potentially through shared utilization of central sensory integration pathways. Objective. This study characterized the relationship between central vestibular integration and cognition in people with MS through measurement of several clinical vestibular functions requiring central sensory integration and multiple cognitive domains. Methods. Forty people with MS and 20 controls completed a battery of vestibular and cognitive examinations targeting different central vestibular integration measures and different domains of cognition, respectively. Performance on these measures was compared between people with MS and controls, and then correlational analyses were undertaken between the vestibular and cognitive measures in the MS sample. Results. People with MS performed worse than controls on all vestibular and cognitive measures. There were consistent correlations between vestibular and cognitive measures in the MS sample. Factor analysis of vestibular functions yielded a single factor hypothesized to represent central vestibular integration that demonstrated a significant relationship with a composite cognitive measure in people with MS. Discussion. Our results suggest that vestibular and cognitive dysfunction may both arise from central sensory processing pathways in people with MS. This connection could be targeted through vestibular rehabilitation techniques that improve central sensory processing and both balance and cognition in people with MS.

Central Vestibular Functions Correlate With Fatigue and Walking Capacity in People With Multiple Sclerosis.

OBJECTIVE: Imbalance and fatigue are among the most common and disabling symptoms of multiple sclerosis (MS). Vestibular rehabilitation studies demonstrate not only improvements in balance but fatigue also, suggesting a relationship between central vestibular integration and fatigue. The objective of this study was to determine whether the relationship between balance and fatigue in people with MS is seen between other measures of central vestibular integration and fatigue and to understand how central vestibular integration measures interrelate. METHODS: This cross-sectional study consisted of 40 people with MS (age = 27-55 years, Expanded Disability Severity Scale score = 1.0-6.5) who completed vestibular ocular reflex testing, subjective visual vertical testing, static posturography, dynamic gait, 2 self-report fatigue surveys, and a 6-Minute Walk Test to assess walking capacity/physical fatigue was completed. Spearman correlations were calculated between variables. RESULTS: Measures of central vestibular integration were significantly correlated with measures of fatigue and walking capacity and with each other. The correlations between physical fatigue and central vestibular functions were larger than self-reported fatigue correlations with central vestibular functions. CONCLUSION: The relationship between balance and fatigue extends to other measures requiring central vestibular integration, suggesting a deficit in central vestibular processing in people with MS. These measures may compliment balance assessment as outcome measures for vestibular rehabilitation in people with MS. Fatigue measures should be included in vestibular rehabilitation as secondary outcomes. IMPACT: Correlations between central vestibular integration and fatigue in people with MS suggest that future studies of vestibular rehabilitation should include fatigue, as a secondary outcome measure as vestibular function and fatigue may share similar a similar etiology in people with MS.

Comprehensive Clinical Assessment of Vestibular Function in Multiple Sclerosis.

BACKGROUND AND PURPOSE: Balance disorders and dizziness are common in people with multiple sclerosis (MS), suggesting dysfunction of the vestibular system. Evaluating how people with MS perform on objective clinical vestibular tools will help broaden understanding of vestibular function in MS. This cross-sectional study's goal was to complete a robust battery of vestibular-ocular reflex (VOR), dynamic visual acuity (DVA), subjective visual vertical (SVV), and cervical and ocular vestibular-evoked myogenic potential (c/oVEMP) tests in people with and without MS. METHODS: Forty people with relapsing-remitting MS (Expanded Disability Status Scale [EDSS] ≤6.5) and 20 controls completed the vestibular testing battery. Results were compared between groups and correlations with EDSS scores were calculated. RESULTS: People with MS were less able to visually cancel their VOR and showed a larger variance in response on SVV. EDSS significantly correlated with VOR cancellation, SVV variance, and DVA lines lost; linear regression showed that VOR cancellation and SVV variance significantly predicted EDSS. DISCUSSION AND CONCLUSION: Vestibular functions requiring central integration of vestibular information, but not reflexive vestibular functions like VEMP, were impaired in people with MS and correlated with EDSS, suggesting that clinical evaluation of functions requiring central integration best evaluates MS-related vestibular dysfunction. Measures assessing central vestibular integration and not vestibular reflexes may be more sensitive to detecting vestibular deficits in people with mild to moderate MS.Video Abstract available for more insight from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A344).

Vestibular, Oculomotor, and Balance Functions in Children With and Without Concussion.

OBJECTIVE: The main objective of this study was to assess whether objective vestibular, oculomotor, and balance functions were impaired in children with a current diagnosis of concussion with vestibular and/or ocular symptoms. SETTING: Data were collected in a vestibular/ocular clinical laboratory. Patient participants were recruited from a concussion clinic in a children's hospital. PARTICIPANTS: Thirty-three children aged 8 to 17 years with a current diagnosis of concussion and vestibular and/or ocular symptoms and 30 children without concussion. DESIGN: Cross-sectional single-visit study. MAIN OUTCOME MEASURES: Eye-tracking rotary chair oculomotor and vestibular measures, vestibular evoked potentials, and static posturography. RESULTS: There were no statistically significant differences on any clinical measure between children with concussion and children without concussion. Younger children without concussion performed significantly worse on several rotary chair and balance measures compared with older children without concussion. CONCLUSIONS: No vestibular, oculomotor, or balance measures were significantly different between children with concussion and children without concussion, suggesting these measures may not be useful in the evaluation of a child with concussion and vestibular and/or oculomotor symptoms. Future research should investigate age effects and other vestibular and oculomotor tests to identify objective findings that better relate to vestibular and/or ocular symptoms in children with concussion.

Inter-rater and test-retest reliability of computerized clinical vestibular tools.

BACKGROUND: Clinical vestibular technology is rapidly evolving to improve objective assessments of vestibular function. Understanding the reliability and expected score ranges of emerging clinical vestibular tools is important to gauge how these tools should be used as clinical endpoints. OBJECTIVE: The objective of this study was to evaluate inter-rater and test-retest reliability intraclass correlation coefficients (ICCs) of four vestibular tools and to determine expected ranges of scores through smallest real difference (SRD) measures. METHODS: Sixty healthy graduate students completed two 1-hour sessions, at most a week apart, consisting of two video head-impulse tests (vHIT), computerized dynamic visual acuity (cDVA) tests, and a smartphone-assisted bucket test (SA-SVV). Thirty students were tested by different testers at each session (inter-rater) and 30 by the same tester (test-retest). ICCs and SRDs were calculated for both conditions. RESULTS: Most measures fell within the moderate ICC range (0.50-0.75). ICCs were higher for cDVA in the inter-rater subgroup and higher for vHITs in the test-retest subgroup. CONCLUSIONS: Measures from the four tools evaluated were moderately reliable. There may be a tester effect on reliabilities, specifically vHITs. Further research should repeat these analyses in a patient population and explore methodological differences between vHIT systems.

Peripheral Vestibular and Balance Function in Athletes With and Without Concussion.

BACKGROUND AND PURPOSE: According to the most recent consensus statement on management of sport-related concussion (SRC), athletes with suspected SRC should receive a comprehensive neurological examination. However, which measures to include in such an examination are not defined. Our objectives were to (1) evaluate test-retest reliability and normative data on vestibular and balance tests in athletes without SRC; (2) compare athletes with and without SRC on the subtests; and (3) identify subtests for concussion testing protocols. METHODS: Healthy athletes (n = 87, mean age 20.6 years; standard deviation = 1.8 years; 39 female and 48 male) and athletes with SRC (n = 28, mean age 20.7 years; standard deviation = 1.9 years; 11 female and 17 male) were tested using rotary chair, cervical vestibular-evoked myogenic potential (c-VEMP), and the Sensory Organization Test (SOT). A subset (n = 43) were tested twice. We analyzed reliability of the tests, and compared results between athletes with and without SRC. RESULTS: Reliability ranged from poor to strong. There was no significant difference between athletes with and without SRC for tests of peripheral vestibular function (ie, rotary chair and c-VEMP). Athletes with SRC had significantly worse scores (P < 0.05) on vestibular-ocular reflex (VOR) cancellation gain, subjective visual vertical and horizontal variance, and all conditions of the SOT. DISCUSSION AND CONCLUSION: SRC did not affect medium frequency VOR or saccular function. SRC did affect the ability to use vestibular inputs for perception of vertical and postural control, as well as ability to cancel the VOR.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A274).

Visuo-oculomotor Function and Reaction Times in Athletes with and without Concussion.

SIGNIFICANCE: Oculomotor tests in concussion commonly show impairment in smooth pursuit and saccadic function. Honing in on the systems likely to be affected by concussion will streamline use of oculomotor function as a supplemental diagnostic and prognostic tool, as well as improve our understanding of the pathophysiology of concussion. PURPOSE: This study investigates oculomotor function between concussed and healthy collegiate athletes and determines measurement test-retest reliability of those tools. METHODS: Eighty-seven healthy athletes were recruited from a U.S. Division 1 sports university and completed a 30-minute vestibular ocular testing battery in an enclosed rotary chair system equipped with 100-Hz eye-tracking goggles. Forty-three individuals completed the battery twice. Twenty-eight individuals with a current diagnosis of concussion also completed the battery. All participants were aged 18 to 24 years. Bivariate statistical tests examined differences in scores across groups, and intraclass coefficients were computed to test reliability. RESULTS: Concussed individuals had significantly longer saccadic, visual, and dual-task reaction times and reduced saccadic accuracy. There was no difference in optokinetic reflex gain, but few concussed individuals tolerated the task. Reaction time latencies and optokinetic gain show moderate test-retest reliability. Smooth pursuit tasks and saccadic accuracies showed poor test-retest reliability. CONCLUSIONS: Saccadic latency was the most sensitive oculomotor function to change after concussion and was reliable over time. Saccadic accuracy was significantly lower in the concussed group but had poor retest reliability. Optokinetic gain may warrant more investigation because of its high test-retest reliability and symptom provocation in concussion, despite not showing a significant difference between groups.

Genetics Influence Neurocognitive Performance at Baseline but Not Concussion History in Collegiate Student-Athletes.

OBJECTIVE: This study investigates 4 single-nucleotide polymorphisms [Apolipoprotein E (APOE), APOE promoter, catechol-O-methyl transferase (COMT), and dopamine D2 receptor] that have been implicated in concussion susceptibility and/or cognitive ability in collegiate student-athletes. DESIGN: Cross-sectional study. SETTING: Neuroscience laboratory at Elon University. PARTICIPANTS: Two hundred fifty division I collegiate student-athletes (66 women, 184 men) from various sports. INTERVENTION: All participants completed Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) testing at baseline concussion testing and had a buccal swab taken for DNA for genotyping. MAIN OUTCOME MEASURES: Self-reported history of concussions and neurocognitive performance were taken from ImPACT. RESULTS: Individuals carrying an ε4 allele in their APOE gene had a significantly slower reaction time (P = 0.001). Individuals homozygous for the Val allele of the COMT gene showed significantly worse impulse control scores (P = 0.014). None of the genotypes were able to predict self-reported concussion history in collegiate student-athletes. CONCLUSIONS: These results indicate that certain genotypes may influence performance on cognitive testing at baseline and that the APOE genotypes may not influence concussion susceptibility as suggested by past studies.

Internal tremor in Parkinson's disease, multiple sclerosis, and essential tremor.

OBJECTIVE: Internal tremor (IT) is a poorly recognized symptom that has been described in Parkinson's disease (PD). Described as a feeling of tremor in the extremities or trunk without actual movement, ITs are not debilitating but can be bothersome to patients. The origin of the sensation is unknown., and ITs may be prevalent in other diseases than PD. The present study sought to expand knowledge about IT by confirming their presence in PD, and determining their prevalence in Multiple Sclerosis (MS), and Essential Tremor (ET). METHODS: A survey was developed in order to determine the prevalence of IT in PD, MS, and ET and to learn what associations with various disease characteristics were present. The survey was administered to 89 consecutive PD, 70 MS, and 11 ET patients. RESULTS: ITs were found to be a prevalent symptom in all three disorders (32.6% of PD, 35.9% of MS, and 54.5% of ET subjects reported experiencing ITs). ITs were found to be associated both with the subjects' perceived levels of anxiety and the presence of visible tremors. CONCLUSION: ITs appear to be a common symptom in all three disorders studied. These results need to be confirmed and compared to appropriate control populations.

The association between fatigue and apathy in patients with either Parkinson's disease or multiple sclerosis.

OBJECTIVE: Fatigue and apathy are common symptoms in both multiple sclerosis (MS) and Parkinson's disease (PD). Both symptoms are considered "amotivational"--fatigue is a lack of energy to start or complete an action and apathy is a loss of interest in activities. Whether the two symptoms are related to each other is not known. The present study sought to investigate the prevalence and severity of fatigue and apathy in MS and PD, and the relationship between the two. METHODS: The Fatigue Severity Scale (FSS) and the Apathy Scale (AS) were administered to 89 consecutive PD and 73 consecutive MS subjects. RESULTS: The mean FSS score for PD subjects was 4.46 and 5.01 for MS; the average total AS score for PD was 12.4 and 12.5 for MS. Using a cutoff of >4.0 on the FSS to assess fatigue, 64% of PD subjects and 74% of MS subjects suffered from severe fatigue. Using an AS cutoff score of >14.0 to determine apathy, 57% of PD subjects and 52% of MS subjects were apathetic. There was a significant correlation between FSS score and AS score in both disorders. FSS average scores and AS total scores were significantly correlated with motor severity in PD but not in MS. Duration of disease was not correlated with either scale scores in either disorder. DISCUSSION: Results confirm that AS and FSS are correlated with each other in both disorders and that MS subjects rate their fatigue significantly higher.