Clinical Assessment of Concussion and Persistent Post-Concussive Symptoms for Neurologists

The Evaluation and Management of Concussion to Optimize Safe Recovery

Concussion is a mild traumatic brain injury causing temporary neurologic dysfunction. Symptoms following concussion are variable and generally are expected to resolve within about 1 month, but some patients experience persistent and prolonged symptoms. An early return to safe, symptom-limited activity is now favored, using targeted rehabilitation and treatments. Accommodations may be needed to facilitate return-to-school and work following concussion. Athletes should not be cleared for a full return to sport until they have recovered from a concussion and completed a return-to-play progression, in addition to returning to work/school fully.

An Exploratory Analysis of Physical Examination Subtypes in Pediatric Athletes With Concussion

OBJECTIVE

Pediatric athletes with concussion present with a variety of impairments on clinical assessment and require individualized treatment. The Buffalo Concussion Physical Examination is a brief, pertinent clinical assessment for individuals with concussion. The purpose of this study was to identify physical examination subtypes in pediatric athletes with concussion within 2 weeks of injury that are relevant to diagnosis and treatment.

DESIGN

Secondary analysis of a published cohort study and clinician consensus.

SETTING

Three university-affiliated sports medicine centers.

PARTICIPANTS

Two hundred seventy children (14.9 ± 1.9 years).

INDEPENDENT VARIABLES

Orthostatic intolerance, horizontal and vertical saccades, smooth pursuits, vestibulo-ocular reflex, near-point convergence, complex tandem gait, neck range of motion, neck tenderness, and neck spasm.

MAIN OUTCOME MEASURES

Correlations between independent variables were calculated, and network graphs were made. k-means and hierarchical clustering were used to identify clusters of impairments. Optimal number of clusters was assessed. Results were reviewed by experienced clinicians and consensus was reached on proposed subtypes.

RESULTS

Physical examination clusters overlapped with each other, and no optimal number of clusters was identified. Clinician consensus suggested 3 possible subtypes: (1) visio-vestibular (horizontal and vertical saccades, smooth pursuits, and vestibulo-ocular reflex), (2) cervicogenic (neck range of motion and spasm), and (3) autonomic/balance (orthostatic intolerance and complex tandem gait).

CONCLUSIONS

Although we identified 3 physical examination subtypes, it seemed that physical examination findings alone are not enough to define subtypes that are both statistically supported and clinically relevant, likely because they do not include symptoms, assessment of mood or cognitive problems, or graded exertion testing.

The Convergent Validity of the SWAY Balance Application to Assess Postural Stability in Military Cadets Recovering from Concussion

Background

Concussions are often accompanied by balance disturbances. Clinically accurate evaluation systems are often expensive, large, and inaccessible to most clinicians. The Sway Balance Mobile Application (SWAY) is an accessible method to quantify balance changes.

Purpose

To determine the known groups and convergent validity of the SWAY to assess balance after a concussion.

Study Design

Case-Control Study.

Methods

Twenty participants with acute concussion and twenty controls were recruited. At initial, one-week, and final return to activity (RTA) evaluations, all participants completed the Sports Concussion Assessment Tool (SCAT-5), and balance control measured by SWAY mBESS and NeuroCom Balance Master Sensory Organization Test (SOT). Mixed model ANOVAs were used to detect differences in SWAY mBESS and NeuroCom SOT scores with time (initial, one-week, final RTA) as the within-subjects factor and group (concussed, healthy) as the between-subjects factor. Spearman's Rho correlations explored the associations between NeuroCom SOT scores, SWAY scores, SCAT-5 symptom scores, and time in days to final RTA.

Results

The sampled population was predominantly male and age (20 ± 1), and BMI differences were insignificant between groups. The SWAY did not detect differences between healthy and concussed participants and did not detect change over time [F(2,40) = .114, p = 0.89; F(2,40)= .276, p =0.60]. When assessing the relationship between the SWAY and the SOT, no correlation was found at any time point (r = -0.317 to -0.062, p > 0.05). Time to RTA demonstrated a moderate correlation with both SCAT-5 symptom severity score (r = .693, p < 0.01) and SCAT-5 total symptom score (r = .611, p < 0.01) at the one-week follow-up.

Conclusion

The SWAY mBESS does not appear to be a valid balance assessment for the concussed patient. The SWAY mBESS in patients with concussion failed to demonstrate convergent validity and did not demonstrate an ability to validate known groups. When assessing the time to final RTA, the one-week post-initial assessment SCAT-5 symptom severity and total scores may help determine the length of recovery in this population.

Level of Evidence

Level 3.

An overview of mild traumatic brain injuries and emerging therapeutic targets

The majority of traumatic brain injuries (TBIs), approximately 90%, are classified as mild (mTBIs). Globally, an estimated 4 million injuries occur each year from concussions or mTBIs, highlighting their significance as a public health crisis. TBIs can lead to substantial long-term health consequences, including an increased risk of developing Alzheimer's Disease, Parkinson's Disease (PD), chronic traumatic encephalopathy (CTE), and nearly doubling one's risk of suicide. However, the current management of mTBIs in clinical practice and the available treatment options are limited. There exists an unmet need for effective therapy. This review addresses various aspects of mTBIs based on the most up-to-date literature review, with the goal of stimulating translational research to identify new therapeutic targets and improve our understanding of pathogenic mechanisms. First, we provide a summary of mTBI symptomatology and current diagnostic parameters such as the Glasgow Coma Scale (GCS) for classifying mTBIs or concussions, as well as the utility of alternative diagnostic parameters, including imaging techniques like MRI with diffusion tensor imaging (DTI) and serum biomarkers such as S100B, NSE, GFAP, UCH-L1, NFL, and t-tau. Our review highlights several pre-clinical concussion models employed in the study of mTBIs and the underlying cellular mechanisms involved in mTBI-related pathogenesis, including axonal damage, demyelination, inflammation, and oxidative stress. Finally, we examine a selection of new therapeutic targets currently under investigation in pre-clinical models. These targets may hold promise for clinical translation and address the pressing need for more effective treatments for mTBIs.

Does Physiologic Post-Concussion Disorder Cause Persistent Post-Traumatic Headache?

PURPOSE OF REVIEW

One system classifies patients with symptoms after concussion into physiologic, vestibulo-ocular, cervicogenic, and mood/cognition post-concussion disorders (PCD) based upon the preponderance of specific symptoms and physical impairments. This review discusses physiologic PCD and its potential relationship to the development of persistent post-traumatic headaches (PPTH).

RECENT FINDINGS

Headache is the most reported symptom after a concussion. Headaches in physiologic PCD are suspected to be due to abnormal cellular metabolism, subclinical neuroinflammation, and dysfunction of the autonomic nervous system (ANS). These abnormalities have been linked to the development of migraine-like and neuralgia-related PPTH. Physiologic PCD is a potential cause of PPTH after a concussion. Future research should focus on how to prevent PPTH in patients with physiologic PCD.

The Rehabilitation Potential of Neurostimulation for Mild Traumatic Brain Injury in Animal and Human Studies

Neurostimulation carries high therapeutic potential, accompanied by an excellent safety profile. In this review, we argue that an arena in which these tools could provide breakthrough benefits is traumatic brain injury (TBI). TBI is a major health problem worldwide, with the majority of cases identified as mild TBI (mTBI). MTBI is of concern because it is a modifiable risk factor for dementia. A major challenge in studying mTBI is its inherent heterogeneity across a large feature space (e.g., etiology, age of injury, sex, treatment, initial health status, etc.). Parallel lines of research in human and rodent mTBI can be collated to take advantage of the full suite of neuroscience tools, from neuroimaging (electroencephalography: EEG; functional magnetic resonance imaging: fMRI; diffusion tensor imaging: DTI) to biochemical assays. Despite these attractive components and the need for effective treatments, there are at least two major challenges to implementation. First, there is insufficient understanding of how neurostimulation alters neural mechanisms. Second, there is insufficient understanding of how mTBI alters neural function. The goal of this review is to assemble interrelated but disparate areas of research to identify important gaps in knowledge impeding the implementation of neurostimulation.

Mild-to-Moderate Traumatic Brain Injury: A Review with Focus on the Visual System

Traumatic Brain Injury (TBI) is a major global public health problem. Neurological damage from TBI may be mild, moderate, or severe and occurs both immediately at the time of impact (primary injury) and continues to evolve afterwards (secondary injury). In mild (m)TBI, common symptoms are headaches, dizziness and fatigue. Visual impairment is especially prevalent. Insomnia, attentional deficits and memory problems often occur. Neuroimaging methods for the management of TBI include computed tomography and magnetic resonance imaging. The location and the extent of injuries determine the motor and/or sensory deficits that result. Parietal lobe damage can lead to deficits in sensorimotor function, memory, and attention span. The processing of visual information may be disrupted, with consequences such as poor hand-eye coordination and balance. TBI may cause lesions in the occipital or parietal lobe that leave the TBI patient with incomplete homonymous hemianopia. Overall, TBI can interfere with everyday life by compromising the ability to work, sleep, drive, read, communicate and perform numerous activities previously taken for granted. Treatment and rehabilitation options available to TBI sufferers are inadequate and there is a pressing need for new ways to help these patients to optimize their functioning and maintain productivity and participation in life activities, family and community.