Examining Initial Post-Concussion Dizziness and Postural Stability as Potential Recovery Predictors

OBJECTIVE

To examine the association between acute post-concussion dizziness, initial symptom severity, and postural stability with time to symptom resolution among adolescents.

BACKGROUND

Identifying early post-concussion symptoms and functional deficits that predict symptom resolution can guide treatment strategies. Dizziness is among the most common concussion symptoms, and existing literature investigating the association between dizziness and recovery time is mixed.

DESIGN/METHODS

Participants underwent initial evaluation = 14 days post-concussion, and self-reported symptom severity using the Post-Concussion Symptom Inventory (PCSI). We used PSCI dizziness ratings to group participants: a difference between current and pre-injury dizziness ≥3 = dizzy; difference <3 = not dizzy. We evaluated postural stability using modified Balance Error Scoring System (mBESS) and tandem gait (TG). Patients were followed until symptom resolution, and our primary outcome of interest was time from concussion to symptom resolution. Using a univariable Cox proportional hazard model, we examined the association of dizziness and symptom resolution time. We then used a multivariable Cox proportional hazard model to adjust for variables that differed between groups.

RESULTS

We examined 89 participants, grouped as dizzy (n = 34; age = 14.7 ± 2.7 years; 7.1 ± 3.4 days post-injury; symptom resolution time = 40.8 ± 5.7 days) or not dizzy (n = 55; age = 14.4 ± 2.3 years; 7.2 ± 3.1 days post-injury; symptom resolution time = 23.3 ± 3.2 days). Upon univariable examination, dizziness was independently associated with symptom resolution time (HR = 0.49; 95% CI: 0.28, 0.83; p = 0.009). After adjusting for potential confounding variables (initial symptom severity, mBESS tandem stance errors, TG time, and loss of consciousness) multivariable model results indicated initial symptom severity was the only variable associated with symptom resolution time (HR = 0.98; 95% CI: 0.96, 0.997; p = 0.025).

CONCLUSIONS

Total symptom severity, but not dizziness or postural stability, was significantly associated with symptom resolution time among adolescents following concussion. Individuals with moderate to severe post-concussion dizziness had higher average symptom scores indicating self-reported dizziness should be interpreted in the context of total concussion symptom burden.

Single-Task and Dual-Task Tandem Gait Performance Across Clinical Concussion Milestones in Collegiate Student-Athletes

OBJECTIVE

To determine the length of time after concussion that impaired tandem gait performance is observed.

DESIGN

Clinical measurement, prospective longitudinal.

SETTING

NCAA collegiate athletic facility.

PARTICIPANTS

Eighty-eight concussed NCAA Division I student-athletes and 30 healthy controls.

INDEPENDENT VARIABLES

Group (concussion/control) and time (Baseline, Acute, Asymptomatic, and RTP).

MAIN OUTCOME MEASURES

Participants completed 4 single-task and dual-task tandem gait trials. The concussion group completed tests at the following time points: preseason (Baseline), within 48 hours after concussion (Acute), on the day symptoms were no longer reported (Asymptomatic), and when cleared to return to sports (RTP). Controls completed the same protocol at similar intervals. The dual-task trials involved minimental style cognitive questions answered simultaneously during tandem gait. We analyzed the best time of the 4 trials, comparing groups with a linear mixed model.

RESULTS

Acutely after concussion, the concussion group performed single-task tandem gait slower (worse) than controls (concussion: 11.36 ± 2.43 seconds, controls: 9.07 ± 1.78 seconds, P < 0.001). The concussion group remained significantly slower than controls (9.95 ± 2.21 vs 8.89 ± 1.65 seconds, P = 0.03) at Asymptomatic day but not RTP. There were significant group (P < 0.001) and time (P < 0.001) effects for dual-task tandem gait. The groups were not significantly different at baseline for single-task (P = 0.95) or dual-task (P = 0.22) tandem gait.

CONCLUSIONS

Our results indicate that tandem gait performance is significantly impaired acutely after concussion, compared with both preseason measures and controls. Postural control impairments were not present when the student-athletes were cleared for RTP. This information can assist clinicians when assessing postural control and determining recovery after a concussive injury.

Health outcomes among former female collegiate gymnasts: the influence of sport specialization, concussion, and disordered eating

Objective: Gymnastics is a popular sport with high injury rates, especially at the collegiate level. There is limited evidence, however, regarding the risks of early specialization in this sport, the rate of concussions in gymnasts, and the long-term effects of disordered eating in gymnasts. We sought to describe health-related outcomes of former collegiate gymnasts and the association with early sport specialization, concussion history, and disordered eating.Methods: We distributed an online survey through social media outlets. A total of 473 former female collegiate gymnasts completed the survey and were grouped according to early (<14 years) specialization, presence or absence of concussion history, and history of disordered eating. We determined the number of participants who had time-loss injuries, injuries requiring surgery, and injuries resulting in retirement. We also evaluated menstrual history, reasons for sport retirement, functional outcome measures, and mental health.Results: The median age of gymnastics specialization was 8 years [interquartile range = 6-11 years]. The proportion of injuries sustained during college did not significantly differ by specialization age. A significantly greater proportion of early specializers required surgery for college sports-related injuries (60% vs. 44%; p = 0.02). Forty-two percent of the respondents reported concussion history, and a greater proportion of those with concussion history reported seeking mental health treatment during college (32% vs. 23%; p = 0.03), and anxiety disorder diagnosis (16% vs. 9%; p = 0.01). Disordered eating history was reported by 34% of the respondents, and this group had a higher proportion of time-loss injury (78% vs 65%; p = 0.004), and osteoporosis (4% vs 0%; p = 0.003) during college, and worse current pain (11.5 vs 10.2; p = 0.007) and physical function (12.2 vs 11.0; p = 0.01) than those without disordered eating.Conclusion: Athletes and clinicians should be aware of the long-term effects of early specialization, concussions, and disordered eating in gymnastics as these issues are common in female collegiate gymnasts.

Association of Hemodynamic and Cerebrovascular Responses to Exercise With Symptom Severity in Adolescents and Young Adults With Concussion

BACKGROUND AND OBJECTIVES

Aerobic exercise has become a useful method to assist with post-concussion management. Exercise can exacerbate concussion symptoms even when symptoms are not apparent at rest. Few studies have examined the reasons for symptom exacerbation during exercise following a concussion. We had two primary objectives. 1) To delineate cardiopulmonary and cerebrovascular responses to exercise in adolescents and young adults with a concussion and healthy controls. 2) To determine the association between cerebrovascular responses and symptom burden.

METHODS

We recruited participants with a recent concussion from a sport concussion clinic between 9/1/2018-2/22/2020. They were included if their concussion occurred <3 weeks before initial testing and if they were symptomatic at rest. Participants were excluded if they sustained a concussion in the past year (excluding index injury), reported history of neurological disorders, or were using medications/devices that may alter neurological function. Participants completed a progressive, symptom-limited, sub-maximal exercise protocol on a stationary bike. We assessed heart rate, blood pressure, fraction of end tidal CO2 (FETCO₂) and middle cerebral artery blood flow velocity (CBF) and cerebrovascular function (vasoreactivity and autoregulation) at seated rest and during exercise.

RESULTS

We conducted 107 exercise tests (40 concussed, 37 healthy participants initially; 30 concussed at follow-up). Concussed participants were tested initially (mean=17.6±2.2 [SD] years old; 55% female; mean=12.5±4.7 days post-concussion) and again 8 weeks later (mean=73.3±9.5 days post-concussion). Control participants (mean=18.3±2.4 years; 62% female) were tested once. FETCO₂ increased throughout the exercise protocol as heart rate increased, reached a plateau, and declined at higher exercise intensities. CO₂ explained >25% of the variation in resting CBF (R²>0.25; p<0.01) in most (73% individuals). Within the concussion group, resting symptom severity and the heart rate at which FETCO₂ reached a plateau explained ∼two-thirds of variation in exercise-induced symptom exacerbation (R ² =0.65; FETCO₂ β=-1.210±0.517[S.E.], p<0.05). There was a moderate, statistically significant relationship between cerebrovascular responses to CO₂ at rest (cerebral vasoreactivity) and cerebrovascular responses to exercise-induced changes in FETCO₂ (R²=0.13, p=0.01).

DISCUSSION

The arterial CO₂ response and symptom exacerbation relationship during post-concussion aerobic exercise may be mediated by increased sensitivity of cerebral vasculature to exercise-related increase in CO₂.

Post-Concussion Dizziness, Sleep Quality, and Postural Instability: A Cross-Sectional Investigation

CONTEXT

Dizziness, postural instability, and poor sleep quality are all commonly reported post-concussion and individually relate to poor outcomes.

OBJECTIVE

To examine sleep quality and postural stability among adolescents who did and did not report dizziness within two weeks of concussion.

DESIGN

Cross-sectional study.

SETTING

Research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Participants ages 12-18 years within 14 days of concussion (n=58, 15.2±1.8 years; 50% female; 7.1±3.1 days post-injury) and uninjured controls (n=73; 15.8±1.3 years; 42% female).

MAIN OUTCOME MEASURES

Participants completed pre-injury and current dizziness ratings on the Post-Concussion Symptom Inventory (PCSI) and current sleep quality on the Pittsburgh Sleep Quality Index (PSQI). Participants also completed postural stability assessments (single/dual-task tandem gait and modified Balance Error Scoring System [mBESS]).

RESULTS

We grouped concussion patients into dizzy (n=21) or not dizzy (n=37) groups based on PCSI dizziness ratings: difference between current and pre-injury dizziness rating >3=dizzy; difference <3=not dizzy. The dizzy and not dizzy groups both reported significantly worse sleep quality than the control group (PSQI score: mean=9.6±3.7 vs 7.2±3.5 vs 4.3±2.6; p<0.001) upon univariable comparison. Similarly, the dizzy group performed slowest on single and dual-task tandem gait, followed by the not dizzy group, then the control group (single-task TG: mean= 27.2±11.7 sec vs 21.2±6.3 vs 14.7±3.6; p<0.001); (dual-task TG: mean=38.4±16.2 sec vs 29.9±7.2 vs 21.6±7.5; p<0.001). Both concussion groups demonstrated significantly more errors than the control group on the mBESS (mean=9.8±5.1 vs 6.9±5.8 vs 3.8±3.5; p<0.001). After controlling for total symptom severity in the multivariable model, tandem gait, but not mBESS or sleep quality, was associated with dizziness.

CONCLUSION

Individuals with post-concussion dizziness also demonstrated impaired tandem gait performance, while poor sleep quality was associated with total symptom severity. Identifying and treating the underlying dysfunction contributing to dizziness and postural instability may guide individualized rehabilitation strategies and facilitate recovery.

Patient perception of dizziness and imbalance does not correlate with gait measures in adolescent athletes post-concussion

BACKGROUND

Dizziness and gait impairments are commonly observed following a concussion, and both are associated with prolonged concussion recovery.

RESEARCH QUESTION

Is there a correlation between combined self-reported dizziness and balance impairment severity with objective gait impairments after concussion?

METHODS

Participants (n = 51; 15.4 ± 1.6 years; 51 % female; 7.3 ± 3.2 days post-injury) age 12-18 years self-reported ratings of dizziness and balance impairment using the Post-Concussion Symptom Inventory (PCSI) within 14 days of injury. Individual ratings of dizziness, balance impairment, and moving clumsily on the PCSI were combined to create a comprehensive dizziness and imbalance score. Participants also completed a smartphone-based gait evaluation under single-task and dual-task conditions. Correlation coefficients (Pearson r for normally distributed and Spearman rho for non-normally distributed variables) were calculated between self-reported symptoms and single and dual-task spatiotemporal gait parameters, specifically step velocity, step time, and step length.

RESULTS

Correlation coefficients indicated that there was low to no correlation between self-reported dizziness and imbalance impairment severity and smartphone-obtained gait parameters under single- or dual-task conditions, including step velocity (single-task: r=-0.22, p = 0.13; dual-task: r=-0.05, p = 0.72), step time (single-task: rho = 0.16, p = 0.27; dual-task: rho = 0.14, p = 0.33), and step length (single-task: r=-0.15, p = 0.30; dual-task: r = 0.03, p = 0.84).

SIGNIFICANCE

Self-reported dizziness and balance impairment severity within the first two weeks of concussion may not reflect objectively measured gait performance, given the lack of association between subjective symptom ratings and functional measures. Further, smartphone collected gait parameters may not provide the necessary sensitivity to detect an association with dizziness. The lack of significant correlation between self-reported symptoms and objective gait performance highlights the importance of using both objective and subjective measures to obtain a more complete picture of concussion deficits.

Executive dysfunction after multiple concussions is not related to cerebrovascular dysfunction

Objective.We investigated the relation between prior concussion history and working memory (WM), self-reported cognitive symptom burden, and cerebrovascular function in adolescents and young adults (14-21 years old).Approach.We recruited 59 participants, 34 clinically diagnosed with a sports-related concussion and 25 controls. Concussed subjects were studied at baseline (within 28 days of their injury) and eight weeks after, while control subjects only had one assessment. We assessed WM (n-back task up to four-back), and neurovascular coupling (cerebrovascular responses at middle cerebral artery duringn-back tasks) using a transcranial Doppler ultrasonograph.Main results.There was no significant difference in WM between controls and concussed participants (p = 0.402). However, WM capacity was lower in those who had sustained ≥3 concussions (7.1% with WM capacity of four) compared to those with their first ever concussion (33.3%) and controls (28.0%, overallp = 0.025). At the sub-acute point (n = 24), self-reported cognitive symptom burden was mostly resolved in all but two participants. Despite the resolution of symptoms, WM performance was not different eight weeks post injury (p = 0.706). Neurovascular coupling was not different between controls and concussed participants regardless of prior concussion history.Significance. Up to 20% of concussed individuals experience covert sequelae lasting beyond the resolution of self-reported overt symptoms. How a prior history of concussion impacts the potential for sequelae is not well established, and the underlying mechanisms are unknown. Despite no alterations in neurovascular coupling, a history of prior concussion was associated with significant deficits in WM capacity, and lasted beyond self-reported cognitive symptom resolution.

Symptom and clinical recovery outcomes for pediatric concussion following early physical activity

OBJECTIVE

Recent research supports initiating physical activity as soon as 24 to 48 hours after concussion to reduce persistent postconcussive symptoms. However, this practice has not been widely adopted. The objective of this study was to evaluate the association of early physical activity with patient-reported and functional outcomes for pediatric patients following a concussion.

METHODS

A retrospective cohort of patients who presented to a pediatric sports medicine clinic (48% female, mean age14.3 ± 2.6 years, and mean 9.8 ± 5.7 days postconcussion) were evaluated. Patients were grouped based on whether they reported engaging in physical activity prior to presenting to the clinic. Patient- and parent-reported symptom frequency (Health and Behavior Inventory), 11 different clinical outcomes (including missed school, memory recall, and balance assessments), the presence of symptoms persisting beyond 28 days, and a subgroup analysis of those patients receiving exercise versus symptom-limiting activity prescriptions were examined. Outcomes were compared between physical activity groups using the Mann-Whitney U-test and the chi-square test. To adjust for the effect of potential confounders, a logistic binary regression model was constructed.

RESULTS

In total, 211 pediatric patients were included, 35 (17%) of whom reported early physical activity. A greater proportion of the no physical activity group reported a headache (85% vs 60%, p = 0.001). The no physical activity group also reported higher patient-reported (23.1 ± 13.4 vs 15.0 ± 13.4, p < 0.001) and parent-reported (19.4 ± 12.7 vs 11.2 ± 10.3, p = 0.001) symptom frequency at the initial visit. The early physical activity group had a lower proportion of patients with persistent symptoms (44% vs 22%, p = 0.02) and a shorter time to symptom resolution (15.6 ± 12.4 days vs 27.2 ± 24.2 days, p = 0.02). After adjusting for potential confounders, early physical activity was associated with 5.8 lower odds of experiencing persistent symptoms (adjusted OR 5.83, 95% CI 2.05-16.61; p = 0.001).

CONCLUSIONS

A significant association between early physical activity and decreased symptom burden was observed. A lower proportion of those patients who engaged in early physical activity experienced persistent symptoms 28 days postinjury. However, low rates of early physical activity prior to the initial clinic visit were also observed, indicating that this approach may not be well known by acute care or primary care providers, or is not widely adopted by patients and families.

Intersection of surgical injuries and pain interference among former female collegiate gymnasts

BACKGROUND

Gymnastics is a competitive sport with numerous health benefits. However, few data exist that examine the lasting effects of injuries in retired gymnasts.

OBJECTIVE

To examine pain interference among former collegiate gymnasts. Specifically, we focused on the relationship between gymnastics-related injuries sustained during middle/high school or college that required surgery and former collegiate gymnasts' current pain. We hypothesized that injuries requiring surgery would be associated with increased pain and reduced function after retirement.

DESIGN

Cross-sectional survey.

SETTING

An online questionnaire was distributed to former female collegiate gymnasts via social media.

PARTICIPANTS

A total of 447 former female collegiate gymnasts completed the survey and were grouped according to whether they indicated an injury during their middle/high school or collegiate gymnastics career that required surgery.

MAIN OUTCOME MEASURES

The association between current pain interference (Patient-Reported Outcomes Measurement Information System [PROMIS] scale) and injuries in middle/high school or college that resulted in surgery. Pain interference elements included current enjoyment of life, ability to concentrate, participation in day-to-day activities, enjoyment of recreational activities, ability to perform errands, and ability to socialize with others.

RESULTS

Those who reported an injury that resulted in surgery (n = 260; mean current age ± SD = 32.8 ± 9.5 years) were younger than those who did not at the time of survey completion (n = 187; current age: 37.0 ± 11.0 years) and reported beginning gymnastics at an earlier age (4.4 ± 2.0 years vs. 5.1 ± 2.5 years; p = .001). There were no statistically significant differences between the groups on any PROMIS questions. In secondary analyses, we found a small but significant association between beginning gymnastics at an earlier age and the odds of requiring surgery (odds ratio = 1.11, 95% confidence interval [CI] = 1.02-1.21; p = .02).

CONCLUSIONS

Most retired gymnasts reported a gymnastics-related injury that required surgery. Gymnasts who start gymnastics at a younger age were more likely to sustain an injury that required surgery, but surgery was not associated with higher levels of pain interference.

Neuromuscular training after concussion to improve motor and psychosocial outcomes: A feasibility trial

OBJECTIVE

To determine the feasibility of an 8-week neuromuscular training program initiated upon return-to-play clearance following concussion.

DESIGN

Feasibility trial.

SETTING

A single sports medicine center.

PARTICIPANTS

We approached n = 54 patients; n = 32 agreed to participate (59%). N = 27 participants returned for their second visit at return-to-play clearance (84%) and were randomized to neuromuscular training (n = 13) or standard-of-care (n = 14).

MAIN OUTCOME MEASURES

Participants completed three assessments: within 14 days post-concussion, immediately after return-to-play clearance, and 8-weeks following return-to-play clearance. The intervention aimed to achieve positive neuromuscular adaptations and occurred 2x/week for 8 weeks under supervision.

RESULTS

N = 2 participants randomized to the intervention elected not to participate, both due to schedule conflicts (e.g., time required to meet with the study team). Participants began the intervention an average of 11 days after return-to-play clearance, the majority (91%) completed >75% of training sessions, and training sessions lasted an average of 18.2 ± 4.8 min. One participant stopped the intervention after 7 training sessions due to time availability.

CONCLUSION

It is feasible to initiate a neuromuscular training program for most athletes shortly after returning to play following concussion. Clinicians and researchers may consider this approach to mitigate the increased musculoskeletal injury risk for concussion patients returning to sports.

Association between post-concussion symptoms and oculomotor deficits among adolescents

PURPOSE

To examine the association between Post-Concussion Symptom Scale (PCSS) scores, Convergence Insufficiency Symptom Survey (CISS) scores, and oculomotor deficits post-concussion.

METHODS

Records of adolescent patients examined in a multidisciplinary concussion clinic between July 2014 and May 2019 were reviewed. PCSS and CISS scores, results of eye examination and oculomotor assessment, concussion history, and demographics were abstracted.

RESULTS

One hundred and forty patient records (median age, 15.3 years; 52 males, presented 109 days (median) from their most recent concussion) met inclusion criteria. Mean total scores on PCSS and CISS were 46.67 ± 25.89 and 27.13 ± 13.22, respectively, and were moderately correlated with each other (r = 0.53, p < .001). Oculomotor deficits were observed in 123 (88%) patients. Step-wise linear regression identified increased PCSS total score to be significantly associated with decreased amplitude of accommodation (p < .001). Increased CISS total score was significantly associated with receded near point of convergence, developmental eye movement test error scores, and cause of concussion.

CONCLUSION

High PCSS scores may indicate an accommodation deficit and thus prompt an oculomotor assessment in patients following a concussion. Using the CISS and a detailed oculomotor assessment may reveal underlying oculomotor deficits, which may benefit from treatment.

Transitory kinesiophobia after sport-related concussion and its correlation with reaction time

OBJECTIVES

To examine kinesiophobia (i.e. fear of movement) among adolescent athletes with concussion compared to controls, and correlations of kinesiophobia with symptoms and reaction time.

DESIGN

Prospective cohort study.

METHODS

We evaluated 49 adolescent athletes twice. The concussion group was assessed within 14 days of injury and at return-to-play clearance. The control group was tested initially and approximately 28 days later. Participants completed Tampa Scale of Kinesiophobia, Post-Concussion Symptom Inventory, and clinical reaction time assessments.

RESULTS

We included 32 concussion participants (15 ± 2 years; 50% female) and 17 controls (16 ± 1 years; 47% female). Acutely (<14 days post-injury), the concussion group reported greater Tampa Scale of Kinesiophobia scores (38.5 ± 5.4 vs. 29.4 ± 6.7; p < 0.001; Cohen's d = 1.54), and a greater proportion of "high" (≥37) scores than controls (69% vs. 6%; p < 0.001). At return-to-play, there were no significant between-group differences (33.3 ± 6.5 vs. 30.8 ± 7.4; p = 0.23; Cohen's d = 0.36); 28% of the concussion group reported "high" Tampa Scale of Kinesiophobia scores. At return-to-play, kinesiophobia was significantly/moderately correlated with clinical reaction time for the concussion group (r = 0.50; p = 0.01).

CONCLUSIONS

Adolescents recovering from concussion commonly reported high kinesiophobia initially postconcussion, while 28% continued to report high kinesiophobia at return-to-play clearance. Additionally, a correlation between Tampa Scale of Kinesiophobia scores and clinical reaction time was observed for the concussion group. This finding would benefit from further study to determine potential perception-behavior relationships following concussion.

The Association between Baseline Eye Tracking Performance and Concussion Assessments in High School Football Players

SIGNIFICANCE

Concussions are complex injuries that require a multifaceted testing battery. Vision impairments are common after concussion, but it is unknown exactly how eye tracking may be affected after injury and how it is associated with other clinical concussion assessments.

PURPOSE

This study aimed to (1) examine the relationship between eye tracking performance (BOX score) and other common concussion evaluations, (2) identify if eye tracking adds novel information that augments baseline concussion evaluations, and (3) examine the effect of age, concussion history, and attention-deficit/hyperactivity disorder on eye tracking and other ophthalmological measures.

METHODS

A total of 102 male high school football athletes (age, 16.0 years; 95% confidence interval, 15.8 to 16.2 years) completed a series of visual and neurocognitive tests during their pre-season baseline assessment. The main outcome measures were BOX score, near point of convergence (NPC) distance, binocular accommodative amplitude (BAA) distance, Standardized Assessment of Concussion score, and Immediate Post-Concussion Assessment and Cognitive Testing composite scores.

RESULTS

BOX score was not significantly associated with symptoms, Standardized Assessment of Concussion score, NPC distance, BAA distance, or any Immediate Post-Concussion Assessment and Cognitive Testing composite scores. Age, concussion history, attention-deficit/hyperactivity disorder, and number of prior years playing football were not significantly associated with BOX score or NPC distance, but there was a significant association between concussion history and greater BAA distance (β = 1.60; 95% confidence interval = 0.19 to 3.01; P < .03). The BOX score cutoff of 10 resulted in a 12% false-positive rate.

CONCLUSIONS

Eye tracking was not significantly associated with the commonly used clinical concussion assessments. These results suggest that an objective eye tracking variable may be a valuable addition to the current concussion battery.

Preseason Vestibular Ocular Motor Screening in Children and Adolescents

OBJECTIVES

The primary purpose of this study was to examine vestibular/ocular motor screening (VOMS) test performance in a sample of healthy youth ice hockey players. A particular focus was to investigate the potential effects of age and pre-existing health conditions, including concussion history, attention-deficit/hyperactivity disorder (ADHD), learning disability (LD), headaches/migraines, and depression/anxiety on preseason baseline VOMS performance, including the near point of convergence (NPC) distance.

DESIGN

Cross-sectional cohort.

SETTING

Outpatient physiotherapy clinic.

PARTICIPANTS

Three hundred eighty-seven male youth hockey players, with an average age of 11.9 years (SD = 2.2, range = 8-17), completed the VOMS and responded to self- or parent-reported demographic and medical history questionnaires during preseason baseline assessments.

INDEPENDENT VARIABLES ASSESSED

Age, sex, and mental and physical health history including ADHD, headaches, depression, anxiety, migraine, and LD.

OUTCOME MEASURE

Vestibular/ocular motor screening.

RESULTS

The large majority of boys scored within normal limits on the VOMS, ie, they reported no symptom provocation of more than 2 points on any VOMS subset (89%) and had a normal NPC distance, ie, <5 cm (78%). The individual VOMS subtests had low abnormality rates, and demographic and pre-existing health conditions, such as age, headache or migraine history, previous neurodevelopmental conditions, or mental health problems, were not associated with clinically meaningful symptom provocation during the VOMS.

CONCLUSIONS

There was a low rate of abnormal findings for the individual VOMS subtests, with the exception of NPC distance, among male youth hockey players during preseason assessment.

Condition-specific health-related quality of life amongst amateur athletes six months and one-year following sport-related concussion: A prospective, follow-up

OBJECTIVE

To prospectively investigate the condition-specific health-related quality of life (HRQoL) of athletes six months and one-year following sport-related concussion.

DESIGN

Prospective, longitudinal study.

SETTING

Clinical research centre at university school of public health.

PARTICIPANTS

Amateur athletes who were diagnosed with sport-related concussion within one-week after presenting to a hospital emergency department were recruited along with sex-, age-, and activity-matched, non-concussed, control athletes. Concussion and control participants were assessed six months and one-year following sport-related concussion and study enrolment, respectively.

MAIN OUTCOME MEASURES

Participants completed the Post-Concussion Symptom Scale and five condition-specific HRQoL patient-reported outcome measures - Headache Impact Test-6, Fatigue Severity Scale, Neck Disability Index, Generalised Anxiety Disorder-7, and Dizziness Handicap Inventory. We performed Frequentist and Bayesian mixed-design analyses of variance to compare the concussion group and control group at both assessments and quantify whether there was greater evidence in favour of the null hypothesis compared with the alternative hypothesis.

RESULTS

At six-month and one-year assessments, the concussion group (n = 47; male = 72%; mean (SD) age = 22.68 (5.07)) and the control group (n = 47; male = 72%; mean (SD) age = 23.81 (4.60)) reported similar clinical symptom severity scores and condition-specific HRQoL. The proportion of athletes in the concussion group with clinically-impaired scores was similar to the proportion of non-concussed athletes with clinically-impaired scores. At six-month and one-year assessments, there was moderate-to-very strong evidence that there was no difference between concussion and control participants' perceptions of the effects of headache, fatigue, neck pain, anxiety, and dizziness on HRQoL.

CONCLUSION

There was moderate-to-very strong evidence in favour of no difference between the concussion and control groups on symptom severity scores and condition-specific HRQoL patient-reported outcome measures at six-month and one-year assessments. These results suggest that condition-specific HRQoL returns to the levels of non-concussed individuals within six months following sport-related concussion.

Influence of Aerobic Exercise Volume on Postconcussion Symptoms

BACKGROUND

Aerobic exercise has emerged as a useful treatment to improve outcomes among individuals who experience a concussion. However, compliance with exercise recommendations and the effect of exercise volume on symptom recovery require further investigation.

PURPOSE

To examine (1) if an 8-week aerobic exercise prescription, provided within 2 weeks of concussion, affects symptom severity or exercise volume; (2) whether prescription adherence, rather than randomized group assignment, reflects the actual effect of aerobic exercise in postconcussion recovery; and (3) the optimal volume of exercise associated with symptom resolution after 1 month of study.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Individuals randomized to an exercise intervention (n = 17; mean age, 17.2 ± 2.0 years; 41% female; initially tested a mean of 11.3 ± 2.8 days after injury) or standard of care (n = 20; mean age, 16.8 ± 2.2 years; 50% female; initially tested a mean of 10.7 ± 3.2 days after injury) completed an aerobic exercise test within 14 days of injury. They returned for assessments 1 month and 2 months after the initial visit. The aerobic exercise group was instructed to exercise 5 d/wk, 20 min/d (100 min/wk), at a target heart rate based on an exercise test at the initial visit. Participants reported their exercise volume each week over the 8-week study period and reported symptoms at each study visit (initial, 1 month, 2 months). Because of low compliance in both groups, there was no difference in the volume of exercise between the 2 groups.

RESULTS

There were no significant symptom severity differences between the intervention and standard-of-care groups at the initial (median Post-Concussion Symptom Inventory, 15 [interquartile range = 10, 42] vs 20 [11, 35.5]; P = .26), 1-month (4 [0, 28] vs 5.5 [0.5, 21.5]; P = .96), or 2-month (6.5 [0, 27.5] vs 0 [0, 4]; P = .11) study visits. Exercise volume was similar between groups (median, 115 [54, 225] vs 88 [28, 230] min/wk for exercise intervention vs standard of care; P = .52). Regardless of group, those who exercised <100 min/wk reported significantly higher symptom severity at the 1-month evaluation compared with those who exercised ≥100 min/wk (median, 1.5 [0, 7.5] vs 12 [4, 28]; P = .03). Exercising ≥160 min/wk successfully discriminated between those with and those without symptoms 1 month after study commencement (classification accuracy, 81%; sensitivity, 90%; specificity, 78%).

CONCLUSION

Greater exercise volume was associated with lower symptom burden after 1 month of study, and an exercise volume >160 min/wk in the first month of the study was the threshold associated with symptom resolution after the first month of the study. Because our observation on the association between exercise volume and symptom level is a retrospective and secondary outcome, it is possible that participants who were feeling better were more likely to exercise more, rather than the exercise itself driving the reduction in symptom severity.

Sport Concussion Assessment Tool-5th Edition (SCAT5): Normative Reference Values for the National Rugby League Women's Premiership

Objective: To establish normative reference values for the Sport Concussion Assessment Tool-5th Edition (SCAT5) for the new National Rugby League Women's Premiership. Methods: Preseason SCAT5 baseline testing was administered individually to all National Rugby League Women's Premiership players (N = 117). Testing was completed by the medical staff. Normative reference values were calculated for the components of the SCAT5, including the Standardized Assessment of Concussion, modified Balance Error Scoring System, and the Symptom Scale. A small case series of players who sustained concussions were included to illustrate the use of the new normative data. Results: The median Standardized Assessment of Concussion total score was 27.0 (M = 26.9, SD = 2.1). The median modified Balance Error Scoring System score was 2.0 (M = 2.4, SD = 2.2). The median number of symptoms score was 1.0 (M = 3.2, SD = 4.7) and the median symptom severity score was 2.0 (M = 5.4, SD = 8.2). The most common baseline symptom was fatigue or low energy (33%), followed by trouble sleeping (24%), headache (23%), neck pain (22%), and difficulty remembering (21%). In the total sample, 41% reported no symptoms. The clinical interpretation of these new normative data to a case series of women with concussions is provided. Conclusions: Normative reference values are provided for the SCAT5 for women who are professional rugby league players. Using these normative data will improve clinical interpretation of SCAT5 scores following a concussion.

Single season re-injury risk after concussion and lower extremity injury among male, collision sport, high school athletes

OBJECTIVES

Research suggests that a recent concussion increases subsequent lower extremity injury risk; however, data in high school athletes is limited. This study evaluates the association between concussion and subsequent injury risk among male, collision sport, high school athletes over a single season.

DESIGN

Retrospective cohort study.

METHODS

Data were obtained from 2005/06-2014/15 in the High School Reporting Information Online database. A two stage, multi-method matching process was used to identify athletes who suffered multiple injuries over a single athletic season. Demographics and injury characteristics were compared with Chi square and Student's t-tests. Multiple Cox Proportional Hazards regression analysis was used to test whether index injury type was associated with hazard of subsequent injury following return to play from index injury.

RESULTS

Overall 1364 HS athletes sustained 2 injuries over a single athletic season (subsequent injury within 45 days of the index injury). Index injuries included 686 (50.2%) lower extremity injuries, 417 (30.6%) upper extremity injuries, and 261 (19.1%) concussions. Hazard of subsequent concussion was increased in the index concussion group relative to the index lower extremity injury group [hazard ratio (HR): 1.60, 95% CI: 1.15-2.23, p = 0.0052]. Hazard of a subsequent lower extremity injury was not significantly different for the index lower extremity injury group relative to the index concussion group [HR: 1.27, 95% CI: 0.98-1.65, p = 0.0728].

CONCLUSIONS

History of recent concussion or recent lower extremity injury are both risk factors for subsequent lower extremity injury in male, collision sport, high school athletes.

Cerebrovascular Neuroprotection after Acute Concussion in Adolescents

OBJECTIVE

To assess acute cerebrovascular function in concussed adolescents (14-21 years of age), whether it is related to resting cerebral hemodynamics, and whether it recovers chronically.

METHODS

Cerebral vasoreactivity and autoregulation, based on middle cerebral artery blood flow velocity, was assessed in 28 concussed participants (≤14 days of injury) and 29 matched controls. The participants in the concussion group returned for an 8-week follow-up assessment. Over the course of those 8-weeks, participants recorded aerobic exercise frequency and duration.

RESULTS

Between groups, demographic, clinical, and hemodynamic variables were not significantly different. Vasoreactivity was significantly higher in the concussed group (p = 0.02). Within the concussed group, 60% of the variability in resting cerebral blood flow velocity was explained by vasoreactivity and two components of autoregulation - falling slope and effectiveness of autoregulation (adjusted R²  = 0.60, p < 0.001). Moreover, lower mean arterial pressure, lower responses to increases in arterial pressure, and lower vasoreactivity were significantly associated with larger symptom burden (adjusted R²  = 0.72, p < 0.01). By the 8-week timepoint, symptom burden, but not vasoreactivity, improved in all but four concussed participants (p < 0.01). 8-week change in vasoreactivity was positively associated with aerobic exercise volume (adjusted R²  = 0.19, p = 0.02).

INTERPRETATION

Concussion resulted in changes in cerebrovascular regulatory mechanisms, which in turn explained the variability in resting cerebral blood flow velocity and acute symptom burden. Furthermore, these alterations persisted chronically despite symptom resolution, but was positively modified by aerobic exercise volume. These findings provide a mechanistic framework for further investigation into underlying cerebrovascular related symptomatology. ANN NEUROL 2021;90:43-51.

Gait Performance Is Associated with Subsequent Lower Extremity Injury following Concussion

PURPOSE

The purpose was to examine gait characteristics between collegiate athletes who did and did not sustain a lower-extremity musculoskeletal (LEMSK) injury in the year after concussion.

METHODS

Thirty-four NCAA collegiate athletes with diagnosed concussions were divided into two groups based on if they did (n = 16) or did not (n = 18) sustain a LEMSK in the year after concussion. Participants completed baseline testing before the start of the season and again at return to play postconcussion. Injuries were tracked using an electronic medical database. Participants were instrumented with three APDM Opal triaxial accelerometers and performed five single-task (ST) and five dual-task (DT) gait trials. Participants traversed a 10-meter walkway, turned around a specified endpoint, and returned to the original line. During DT, participants simultaneously walked and answered mini-mental style questions. A linear mixed-effects model assessed interactions and/or main effects between groups for gait speed, double support time, cadence, stride length, and cognitive accuracy.

RESULTS

The LEMSK group walked slower (ST, 1.15 ± 0.10 m·s; DT, 1.01 ± 0.10 m·s) than the uninjured group (ST, 1.23 ± 0.11 m·s; DT, 1.10 ± 0.11 m·s) during both ST (P = 0.04) and DT (P = 0.03). The injury group spent longer in double support (ST, 20.19% ± 2.34%; DT, 21.92% ± 2.13%) than the uninjured group (ST, 18.16% ± 2.60%; DT, 20.00% ± 2.32%) during both ST (P = 0.02) and DT (P = 0.02). The injury group had a significantly lower cognitive accuracy (89.56% ± 6.48%) than the uninjured group (95.40% ± 7.08%) across time points (P = 0.02).

CONCLUSIONS

There were significant differences in gait characteristics and cognitive accuracy between those who did and did not sustain a LEMSK injury after concussion. The LEMSK group demonstrated a conservative gait strategy both before and after their concussive injury.

Collision and Contact Sport Participation and Quality of Life Among Adolescent Athletes

CONTEXT

Researchers investigating collision and contact sport participation during high school have found mixed results. Understanding the association between current contact and collision sport participation and quality-of-life outcomes can enhance our knowledge about the risks and benefits of sport participation.

OBJECTIVE

To examine quality-of-life outcomes among high school athletes who reported participation in collision and contact sports in the year preceding assessment compared with no- or limited-contact sport athletes.

DESIGN

Cross-sectional study.

SETTING

Preparticipation physical examination.

PATIENTS OR OTHER PARTICIPANTS

High school athletes 13 to 18 years of age.

MAIN OUTCOME MEASURE(S)

We obtained sport participation and Patient-Reported Outcomes Measurement Information System (PROMIS) Pediatric-25 outcomes, which assess self-reported, quality-of-life domains in the preceding 7 days (ie, state assessment). Our grouping variable was collision and contact versus no- or limited-contact sport participation during the year preceding assessment. We used multivariable linear regression models to identify the associations between PROMIS scores and collision and contact sport participation and adjusted for sex; age; history of bone, muscle, ligament, or tendon injury; history of acute fracture or dislocation; and history of concussion.

RESULTS

A total of 143 (51%) athletes reported collision and contact sport participation (24% female, mean age = 15.1 ± 1.7 years) and 138 (49%) reported no- or limited-contact sport participation (66% female, mean age = 15.4 ± 1.2 years). A higher proportion of collision and contact sport athletes reported a history of time loss for bone, muscle, ligament, and tendon injuries (51% versus 29%, P < .001) and for acute fracture or dislocation (46% versus 26%, P < .001) than did no- or limited-contact athletes. After adjusting for covariates, we found that collision and contact sport participation was significantly associated with lower state anxiety (β = -1.072, 95% confidence interval = -1.834, -0.310, P = .006) and depressive (β = -0.807, 95% confidence interval = -1.484, -0.130, P = .020) symptom scores.

CONCLUSIONS

Collision and contact sport athletes reported fewer anxiety and depressive symptoms in the week preceding evaluation than did no- or limited-contact sport athletes, but they had more extensive orthopaedic injury histories. Potential benefits and risks are associated with collision and contact sport participation. These data reinforce the need to examine the assumption that youth collision and contact sports are associated with negative quality of life.

Is near point of convergence associated with symptom profiles or recovery in adolescents after concussion?

Our purpose was to compare the clinical and injury characteristics of concussion patients with a receded near point of convergence (NPC) vs those without a receded NPC. Concussion patients were seen within 14 days of injury. We compared those with receded a NPC (>6 cm) break point distance and those with a normal NPC distance on symptom, behavioral, and clinical assessments. We also compared NPC break points between those who did/did not recover within 28 days of injury. 123 patients completed the assessment. 77/123 (63%) of participants demonstrated a receded NPC when tested within 14 days of injury. Those with receded a NPC break point (n = 77; mean = 14.9, SD = 1.5 years; 47% female) were significantly younger than those with a normal NPC break point (n = 46; mean = 15.7, SD = 1.7 years; 46% female). The receded NPC break point group had a significantly greater proportion of patients reporting headaches (86% vs. 61%), as well as significantly greater cognitive (mean = 13.4, SD = 8.7 vs. mean = 8.8, SD = 8.6), somatic (mean = 10.0, SD = 5.9 vs. mean = 6.9, SD = 6.6), and overall (mean = 23.7, SD = 13.6 vs. mean = 15.8, SD = 14.4) symptom severity. Our multivariable model indicated among all potential predictor variables, more severe somatic symptoms were significantly associated with a greater NPC break point (β = 0.26; 95% CI = 0.01, 0.52). The group who went onto experience persistent symptoms had a significantly greater NPC break point at initial evaluation than those without persistent symptoms (mean = 9.7, SD = 7.5 cm vs. mean = 7.0, SD = 4.0 cm). Those with a receded NPC break point at initial evaluation showed an increased symptom burden, most notable with somatic symptoms, compared with those without a receded NPC break point.

Concussion-Symptom Rating Correlation Between Pediatric Patients and Their Parents

CONTEXT

Understanding how parents and their children perceive concussion symptoms may provide insights into optimal concussion-management strategies.

OBJECTIVE

To examine patient-parent correlations and agreement on concussion-symptom ratings, to identify differences in patient-parent symptom reporting between children (8-12 years of age) and adolescents (13-18 years of age), and to evaluate the correlation between patient and parent initial symptom-severity ratings with symptom duration and return-to-play time.

DESIGN

Cross-sectional study.

SETTING

Primary care sports medicine clinic.

PATIENTS OR OTHER PARTICIPANTS

A total of 267 patients aged 8 to 18 years seen for care within 21 days of sustaining a concussion. Patients were classified as children (n = 65; age = 11.3 ± 1.4 years; age range, 8-12 years) or adolescents (n = 202; age = 15.5 ± 1.4 years; age range, 13-18 years).

MAIN OUTCOME MEASURE(S)

Each patient and his or her parent (or legal guardian) completed a concussion-symptom-frequency inventory, the Health and Behavior Inventory (HBI), at the initial postinjury examination. Patients were followed until they no longer reported concussion symptoms (symptom-resolution time) and were allowed to return to unrestricted sport participation (return-to-play time).

RESULTS

At the initial examination (8.9 ± 5.2 days postinjury), the symptom-frequency correlation between children and their parents was high (rs = 0.88; 95% confidence interval [CI] = 0.80, 0.95). Adolescents' symptom-frequency reports were also highly correlated with those of their parents (rs = 0.78; 95% CI = 0.71, 0.85). However, the child-parent correlation was higher than the adolescent-parent agreement (z = 2.21, P = .03). Greater patient (consolidated child and adolescent) HBI ratings were associated with longer symptom-resolution times (coefficient = 0.019; 95% CI = 0.007, 0.031; P = .002) and longer return-to-play times (coefficient = 0.012; 95% CI = 0.002, 0.022; P = .02), whereas parent HBI ratings were not.

CONCLUSIONS

Our findings may help to set expectations regarding concussion-symptom durations and return-to-play timing for pediatric patients and their families. Given the patient-parent correlations in our sample, substantial reporting discrepancies between patients and their parents may be a relevant factor for clinicians to investigate further during concussion evaluations.

The diagnostic and prognostic utility of the dual-task tandem gait test for pediatric concussion

BACKGROUND

The tandem gait test has gained interest recently for assessment of concussion recovery. The purpose of our study was to determine the prognostic and diagnostic use of the single- and dual-task tandem gait test, alongside other clinical measures, within 10 days of pediatric concussion.

METHODS

We assessed 126 patients post-concussion (6.3 ± 2.3 days post-injury, mean ± SD) at a pediatric sports medicine clinic and compared them to 58 healthy controls (age: 15.6 ± 1.3 years; 43% female). We also compared the 31 patients with concussion who developed persistent post-concussion symptoms (PPCS) (age = 14.9 ± 2.0 years; 48% female) to the 81 patients with concussion who did not develop PPCS following the initial assessment (age: 14.1 ± 3.0 years; 41% female). All subjects completed a test battery, and concussion patients were monitored until they experienced concussion-symptom resolution. The test battery included tandem gait (single-task, dual-task (performing tandem gait while concurrently completing a cognitive test) conditions), modified Balance Error Scoring System (mBESS), and concussion symptom assessment (Health and Behavior Inventory). We defined PPCS as symptom resolution time > 28 days post-concussion for the concussion group. Measurement outcomes included tandem gait time (single- and dual-task), dual-task cognitive accuracy, mBESS errors (single/double/tandem stances), and symptom severity.

RESULTS

The concussion group completed the single-task (mean difference = 9.1 s, 95% confidential interval (95%CI): 6.1-12.1) and dual-task (mean difference = 12.7 s, 95%CI: 8.7-16.8) tandem gait test more slowly than the control group. Compared to those who recovered within 28 days of concussion, the PPCS group had slower dual-task tandem gait test times (mean difference = 7.9 s, 95%CI: 2.0-13.9), made more tandem-stance mBESS errors (mean difference = 1.3 errors, 95%CI: 0.2-2.3), and reported more severe symptoms (mean difference = 26.6 Health and Behavior Inventory rating, 95%CI: 21.1-32.6).

CONCLUSION

Worse dual-task tandem gait test time and mBESS tandem stance performance predicted PPCS in pediatric patients evaluated within 10 days of concussion. Tandem gait assessments may provide valuable information augmenting common clinical practices for concussion management.